diff --git a/molecularnodes/__init__.py b/molecularnodes/__init__.py
index 80869f6d..398caa3e 100644
--- a/molecularnodes/__init__.py
+++ b/molecularnodes/__init__.py
@@ -13,7 +13,8 @@
 
 import bpy
 from bpy.app.handlers import frame_change_post, load_post, save_post
-
+from bpy.props import PointerProperty, CollectionProperty
+from .handlers import update_trajectories
 from . import entities, operators, props, session, ui
 from .utils import add_current_module_to_path
 from .ui import pref
@@ -24,8 +25,8 @@
     ui.CLASSES
     + operators.CLASSES
     + entities.CLASSES
+    + props.CLASSES
     + [
-        props.MolecularNodesObjectProperties,
         MN_PT_Scene,
     ]
     + pref.CLASSES
@@ -56,14 +57,13 @@ def register():
 
     save_post.append(session._pickle)
     load_post.append(session._load)
-    frame_change_post.append(entities.trajectory.handlers.update_trajectories)
+    frame_change_post.append(update_trajectories)
 
     bpy.types.Scene.MNSession = session.MNSession()
-    bpy.types.Object.mn = bpy.props.PointerProperty(
-        type=props.MolecularNodesObjectProperties
-    )
-    bpy.types.Object.mn_trajectory_selections = bpy.props.CollectionProperty(
-        type=entities.trajectory.selections.TrajectorySelectionItem
+    bpy.types.Object.mn = PointerProperty(type=props.MolecularNodesObjectProperties)
+    bpy.types.Scene.mn = PointerProperty(type=props.MolecularNodesSceneProperties)
+    bpy.types.Object.mn_trajectory_selections = CollectionProperty(
+        type=entities.trajectory.props.TrajectorySelectionItem
     )
 
 
@@ -81,7 +81,8 @@ def unregister():
 
     save_post.remove(session._pickle)
     load_post.remove(session._load)
-    frame_change_post.remove(entities.trajectory.handlers.update_trajectories)
+    frame_change_post.remove(update_trajectories)
     del bpy.types.Scene.MNSession
+    del bpy.types.Scene.mn
     del bpy.types.Object.mn
     del bpy.types.Object.mn_trajectory_selections
diff --git a/molecularnodes/blender_manifest.toml b/molecularnodes/blender_manifest.toml
index c19b7498..d9dbc77b 100644
--- a/molecularnodes/blender_manifest.toml
+++ b/molecularnodes/blender_manifest.toml
@@ -35,16 +35,16 @@ wheels = [
 	"./wheels/biotite-0.41.2-cp311-cp311-macosx_11_0_arm64.whl",
 	"./wheels/biotite-0.41.2-cp311-cp311-manylinux_2_17_x86_64.manylinux2014_x86_64.whl",
 	"./wheels/biotite-0.41.2-cp311-cp311-win_amd64.whl",
-	"./wheels/contourpy-1.3.0-cp311-cp311-macosx_10_9_x86_64.whl",
-	"./wheels/contourpy-1.3.0-cp311-cp311-macosx_11_0_arm64.whl",
-	"./wheels/contourpy-1.3.0-cp311-cp311-manylinux_2_17_x86_64.manylinux2014_x86_64.whl",
-	"./wheels/contourpy-1.3.0-cp311-cp311-win_amd64.whl",
+	"./wheels/contourpy-1.3.1-cp311-cp311-macosx_10_9_x86_64.whl",
+	"./wheels/contourpy-1.3.1-cp311-cp311-macosx_11_0_arm64.whl",
+	"./wheels/contourpy-1.3.1-cp311-cp311-manylinux_2_17_x86_64.manylinux2014_x86_64.whl",
+	"./wheels/contourpy-1.3.1-cp311-cp311-win_amd64.whl",
 	"./wheels/cycler-0.12.1-py3-none-any.whl",
 	"./wheels/fasteners-0.19-py3-none-any.whl",
-	"./wheels/fonttools-4.54.1-cp311-cp311-macosx_10_9_universal2.whl",
-	"./wheels/fonttools-4.54.1-cp311-cp311-macosx_11_0_arm64.whl",
-	"./wheels/fonttools-4.54.1-cp311-cp311-manylinux_2_17_x86_64.manylinux2014_x86_64.whl",
-	"./wheels/fonttools-4.54.1-cp311-cp311-win_amd64.whl",
+	"./wheels/fonttools-4.55.0-cp311-cp311-macosx_10_9_universal2.whl",
+	"./wheels/fonttools-4.55.0-cp311-cp311-macosx_10_9_x86_64.whl",
+	"./wheels/fonttools-4.55.0-cp311-cp311-manylinux_2_17_x86_64.manylinux2014_x86_64.whl",
+	"./wheels/fonttools-4.55.0-cp311-cp311-win_amd64.whl",
 	"./wheels/joblib-1.4.2-py3-none-any.whl",
 	"./wheels/kiwisolver-1.4.7-cp311-cp311-macosx_10_9_x86_64.whl",
 	"./wheels/kiwisolver-1.4.7-cp311-cp311-macosx_11_0_arm64.whl",
@@ -62,7 +62,7 @@ wheels = [
 	"./wheels/msgpack-1.1.0-cp311-cp311-manylinux_2_17_x86_64.manylinux2014_x86_64.whl",
 	"./wheels/msgpack-1.1.0-cp311-cp311-win_amd64.whl",
 	"./wheels/networkx-3.4.2-py3-none-any.whl",
-	"./wheels/packaging-24.1-py3-none-any.whl",
+	"./wheels/packaging-24.2-py3-none-any.whl",
 	"./wheels/pandas-2.2.3-cp311-cp311-macosx_10_9_x86_64.whl",
 	"./wheels/pandas-2.2.3-cp311-cp311-macosx_11_0_arm64.whl",
 	"./wheels/pandas-2.2.3-cp311-cp311-manylinux_2_17_x86_64.manylinux2014_x86_64.whl",
@@ -81,7 +81,7 @@ wheels = [
 	"./wheels/six-1.16.0-py2.py3-none-any.whl",
 	"./wheels/starfile-0.5.6-py3-none-any.whl",
 	"./wheels/threadpoolctl-3.5.0-py3-none-any.whl",
-	"./wheels/tqdm-4.66.6-py3-none-any.whl",
+	"./wheels/tqdm-4.67.0-py3-none-any.whl",
 	"./wheels/typing_extensions-4.12.2-py3-none-any.whl",
 	"./wheels/tzdata-2024.2-py2.py3-none-any.whl",
 ]
diff --git a/molecularnodes/entities/ensemble/cif.py b/molecularnodes/entities/ensemble/cif.py
index 06be969d..a206d7f6 100644
--- a/molecularnodes/entities/ensemble/cif.py
+++ b/molecularnodes/entities/ensemble/cif.py
@@ -30,16 +30,15 @@ def _get_structure(self, extra_fields: str = None, sec_struct=True, bonds=True):
         # which can be extracted with the get_component()
         try:
             array = pdbx.get_structure(self.file, extra_fields=extra_fields)
-            try:
-                array.set_annotation(
-                    "sec_struct", _get_secondary_structure(array, self.file)
-                )
-            except KeyError:
-                warnings.warn("No secondary structure information.")
-            try:
-                array.set_annotation("entity_id", _get_entity_id(array, self.file))
-            except KeyError:
-                warnings.warn("Non entity_id information.")
+            annotations = {
+                "sec_struct": _get_secondary_structure,
+                "entity_id": _get_entity_id,
+            }
+            for key, func in annotations.items():
+                try:
+                    array.set_annotation(key, func(array, self.file))
+                except KeyError:
+                    pass
 
         except InvalidFileError:
             array = pdbx.get_component(self.file)
diff --git a/molecularnodes/entities/molecule/ui.py b/molecularnodes/entities/molecule/ui.py
index 03fe866f..e2b7cb93 100644
--- a/molecularnodes/entities/molecule/ui.py
+++ b/molecularnodes/entities/molecule/ui.py
@@ -14,6 +14,7 @@
 from .pdb import PDB
 from .pdbx import BCIF, CIF
 from .sdf import SDF
+from ...style import STYLE_ITEMS
 
 
 def parse(filepath) -> Molecule:
@@ -103,20 +104,6 @@ def load_local(
     return mol
 
 
-STYLE_ITEMS = (
-    ("spheres", "Spheres", "Space-filling atoms style."),
-    ("cartoon", "Cartoon", "Secondary structure cartoons"),
-    ("surface", "Surface", "Solvent-accsible surface."),
-    ("ribbon", "Ribbon", "Continuous backbone ribbon."),
-    ("sticks", "Sticks", "Sticks for each bond."),
-    ("ball_and_stick", "Ball and Stick", "Spheres for atoms, sticks for bonds"),
-    ("preset_1", "Preset 1", "A pre-made combination of different styles"),
-    ("preset_2", "Preset 2", "A pre-made combination of different styles"),
-    ("preset_3", "Preset 3", "A pre-made combination of different styles"),
-    ("preset_4", "Preset 4", "A pre-made combination of different styles"),
-)
-
-
 class Import_Molecule(bpy.types.Operator):
     style: EnumProperty(  # type: ignore
         name="Style",
@@ -381,7 +368,7 @@ def execute(self, context):
 
         style = None
         if scene.MN_import_node_setup:
-            style = scene.MN_import_style
+            style = scene.mn.import_style
 
         centre = ""
         if scene.MN_import_centre:
@@ -423,7 +410,7 @@ def execute(self, context):
         scene = context.scene
         file_path = scene.MN_import_local_path
 
-        style = scene.MN_import_style
+        style = scene.mn.import_style
         if not scene.MN_import_node_setup:
             style = None
 
@@ -467,7 +454,7 @@ def execute(self, context):
 
         style = None
         if scene.MN_import_node_setup:
-            style = scene.MN_import_style
+            style = scene.mn.import_style
 
         centre = ""
         if scene.MN_import_centre:
@@ -559,7 +546,7 @@ def panel_wwpdb(layout, scene):
     row = options.row()
     row.prop(scene, "MN_import_node_setup", text="")
     col = row.column()
-    col.prop(scene, "MN_import_style")
+    col.prop(scene.mn, "import_style")
     col.enabled = scene.MN_import_node_setup
 
     row_centre = options.row()
@@ -601,7 +588,7 @@ def panel_alphafold(layout, scene):
     row = options.row()
     row.prop(scene, "MN_import_node_setup", text="")
     col = row.column()
-    col.prop(scene, "MN_import_style")
+    col.prop(scene.mn, "import_style")
     col.enabled = scene.MN_import_node_setup
 
     row_centre = options.row()
@@ -638,7 +625,7 @@ def panel_local(layout, scene):
     row = options.row()
     row.prop(scene, "MN_import_node_setup", text="")
     col = row.column()
-    col.prop(scene, "MN_import_style")
+    col.prop(scene.mn, "import_style")
     col.enabled = scene.MN_import_node_setup
 
     row_centre = options.row()
diff --git a/molecularnodes/entities/trajectory/__init__.py b/molecularnodes/entities/trajectory/__init__.py
index 3695176e..23831404 100644
--- a/molecularnodes/entities/trajectory/__init__.py
+++ b/molecularnodes/entities/trajectory/__init__.py
@@ -1,6 +1,7 @@
 from . import selections
 from . import ui
+from . import props
 from .ui import load
 from .trajectory import Trajectory
 
-CLASSES = selections.CLASSSES + ui.CLASSES
+CLASSES = props.CLASSSES + ui.CLASSES
diff --git a/molecularnodes/entities/trajectory/dna.py b/molecularnodes/entities/trajectory/dna.py
index 36759a29..da17254e 100644
--- a/molecularnodes/entities/trajectory/dna.py
+++ b/molecularnodes/entities/trajectory/dna.py
@@ -1,324 +1,84 @@
-import numpy as np
+from MDAnalysis import Universe
 import bpy
+from bpy.props import StringProperty
+from .ops import TrajectoryImportOperator
 from ... import color
-from ...blender import mesh, coll, nodes
+from ...blender import coll, nodes
 from ... import bpyd
 from ...bpyd import AttributeTypes
 
-bpy.types.Scene.MN_import_oxdna_topology = bpy.props.StringProperty(
-    name="Toplogy",
-    description="File path for the topology to import (.top)",
-    subtype="FILE_PATH",
-    maxlen=0,
-)
-bpy.types.Scene.MN_import_oxdna_trajectory = bpy.props.StringProperty(
-    name="Trajectory",
-    description="File path for the trajectory to import (.oxdna / .dat)",
-    subtype="FILE_PATH",
-    maxlen=0,
-)
-bpy.types.Scene.MN_import_oxdna_name = bpy.props.StringProperty(
-    name="Name",
-    description="Name of the created object.",
-    default="NewOrigami",
-    maxlen=0,
-)
+from .oxdna.OXDNAParser import OXDNAParser
+from .oxdna.OXDNAReader import OXDNAReader
+from .trajectory import Trajectory
 
+DNA_SCALE = 10
 
-def base_to_int(bases: np.array) -> np.array:
-    """
-    Convert an array of DNA bases to their corresponding MN integer values.
 
-    Parameters
-    ----------
-    bases : np.array
-        Array of DNA bases.
-
-    Returns
-    -------
-    np.array
-        Array of corresponding integer values for the DNA bases.
-    """
-    # Values for internal Molecular Nodes use. Defined in data.py
-    base_lookup = {"A": 30, "C": 31, "G": 32, "T": 33}
-
-    ints = np.array([base_lookup.get(base, -1) for base in bases])
-
-    return ints
-
-
-def is_new_topology(filepath):
-    with open(filepath) as f:
-        firstline = f.readline()
-
-    return "5 -> 3" in firstline
-
-
-def read_topology_new(filepath):
-    with open(filepath, "r") as file:
-        contents = file.read()
-
-    lines = np.array(contents.split("\n"))
-
-    def read_seq_line(line):
-        sequence = line.split(" ")[0]
-        return np.array([c for c in sequence])
-
-    strands = []
-    counter = 0
-
-    for i, line in enumerate(lines[1:]):
-        bases = read_seq_line(line)
-        arr = np.zeros((len(bases), 4), dtype=int)
-        idx = np.array(range(len(bases)), dtype=int)
-        arr[:, 0] = i + 1  # strand ID
-        arr[:, 1] = base_to_int(bases)  # base
-        bond_3 = idx - 1 + counter
-        bond_5 = idx + 1 + counter
-        bond_3[0] = -1
-        bond_5[-1] = -1
-        arr[:, 2] = bond_3
-        arr[:, 3] = bond_5
-
-        strands.append(arr)
-        counter += len(bases)
-
-    return np.vstack(strands)
-
-
-def read_topology_old(filepath):
-    """
-    Read the topology from a file and convert it to a numpy array.
-
-
-    Strand assignment
-    |  Base assignment
-    |  |  3' Bonded base to the current base (index based on row)
-    |  |  |   5' Bonded base to the current base (index based on row)
-    |  |  |   |
-    S  B  3'  5'
-    S  B  3'  5'
-    S  B  3'  5'
-
-    Parameters
-    ----------
-    filepath : str
-        The path to the file containing the topology.
-
-    Returns
-    -------
-    numpy.ndarray
-        The topology as a integer numpy array. Base assignment is (30, 31, 32, 33) where
-        this corresponds to (A, C, G, T) for use inside of Molecular Nodes.
-
-    """
-
-    with open(filepath, "r") as file:
-        contents = file.read()
-
-    lines = np.array(contents.split("\n"))
-    # metadata = lines[0]
-
-    # read the topology from the file sans the first metadata line
-    # have to initially read as strings, then convert bases to numeric later
-    array_str = np.loadtxt(lines[1:], dtype=str)
-
-    # convert the columns to numeric
-    array_int = np.zeros(array_str.shape, dtype=int)
-    array_int[:, (0, 2, 3)] = array_str[:, (0, 2, 3)].astype(
-        int
-    )  # easy convert numeric columns to int
-    # convert bases (A, C, G, T) to (30, 31, 32, 33)
-    array_int[:, 1] = base_to_int(array_str[:, 1])
-
-    return array_int
-
-
-def read_trajectory(filepath):
-    """
-    Read an oxDNA trajectory file and return an array of frames.
-
-    Each frame becomes a 2D array in a stack. Each frame has 5 three-component vectors.
-    The vectors are: (position, base_vector, base_normal, veclocity, angular_velocity),
-    which totals 15 columns in the array. The (velocity, angular_velocity) are optional
-    and can sometimes not appear in the trajectory.
-
-    Parameters
-    ----------
-    filepath : str
-        The path to the trajectory file.
-
-    Returns
-    -------
-    frames : ndarray
-        An array of frames, where each frame is a 2D array of positions
-
-    """
-    # Open the file and read its contents
-    with open(filepath, "r") as file:
-        contents = file.read()
-
-    # Split the contents into lines
-    lines = np.array(contents.split("\n"))
-    is_meta = np.char.find(lines, "=") > 0
-
-    group_id = np.cumsum(np.append([True], np.diff(is_meta)))
-    groups = np.unique(group_id)
-
-    frames = []
-
-    for group in groups:
-        mask = group == group_id
-        if "=" in lines[mask][0]:
-            continue
-
-        arr = np.loadtxt(lines[mask])
-        frames.append(arr)
-
-    return np.stack(frames)
-
-
-def store_named_attributes_to_dna_mol(obj, frame, scale_dna=0.1):
-    attributes = ("base_vector", "base_normal", "velocity", "angular_velocity")
-    for i, att in enumerate(attributes):
-        col_idx = np.array([3, 4, 5]) + i * 3
-
-        try:
-            data = frame[:, col_idx]
-        except IndexError as e:
-            print(f"Unable to get {att} attribute from coordinates. Error: {e}")
-            continue
-
-        if att != "angular_velocity":
-            data *= scale_dna
-
-        bpyd.store_named_attribute(
-            obj=obj, data=data, name=att, atype=AttributeTypes.FLOAT_VECTOR
+class OXDNA(Trajectory):
+    def __init__(self, universe: Universe, world_scale: float = 0.01):
+        super().__init__(universe=universe, world_scale=world_scale)
+        self._att_names = (
+            "base_vector",
+            "base_normal",
+            "velocity",
+            "angular_velocity",
         )
 
+    def _create_object(self, style: str = "oxdna", name: str = "NewUniverseObject"):
+        self.object = bpyd.create_object(
+            name=name,
+            collection=coll.mn(),
+            vertices=self.univ_positions * self.world_scale * DNA_SCALE,
+            edges=self.bonds,
+        )
+        self.object.mn.uuid = self.uuid
+        self.object.mn.molecule_type = "md"
+        self._update_timestep_values()
+
+        for name in ("chain_id", "res_id", "res_name"):
+            if name == "res_name":
+                att_name = "res_num"
+            else:
+                att_name = name
+            self.store_named_attribute(getattr(self, att_name), name)
+
+        self.store_named_attribute(
+            data=color.color_chains_equidistant(self.chain_id),
+            name="Color",
+            atype=AttributeTypes.FLOAT_COLOR,
+        )
 
-def toplogy_to_bond_idx_pairs(topology: np.ndarray):
-    """
-    Convert the given topology array into pairs of indices representing each distinct bond.
-
-    Strand assignment
-    |  Base assignment
-    |  |  3' Bonded base to the current base (index based on row)
-    |  |  |  5' Bonded base to the current base (index based on row)
-    |  |  |  |
-    1  A -1  1
-    1  G  0  2
-    1  C  1 -1
-
-    The topology above becomes:
-    np.array([[0, 1], [2, 1]])
-
-    The order of the bond indices doesn't matter to Blender.
-
-    Parameters:
-    topology (np.ndarray): Numeric numpy array representing the topology.
-
-    Returns:
-    np.ndarray: Array of pairs of indices representing each distinct bond.
-    """
-
-    # to get pairs of indices which represent each distinct bond, which are needed for
-    # edge creation in Blender, take each bonded column and create a 'bond' with itself
-    idx = np.array(list(range(topology.shape[0])))
-    bond_3 = np.vstack((idx, topology[:, 2])).reshape((len(idx), 2))
-    bond_5 = np.vstack((idx, topology[:, 3])).reshape((len(idx), 2))
-    bonds = np.vstack((bond_3, bond_5))
-
-    # drop where either bond is -1 (not bonded) from the bond indices
-    mask = bonds == -1
-    mask = np.logical_not(mask.any(axis=1))
-
-    bond_idxs = np.unique(bonds[mask, :], axis=0)
-
-    return np.sort(bond_idxs, axis=1)
-
-
-def load(top, traj, name="oxDNA", setup_nodes=True, world_scale=0.01):
-    # the scale of the oxDNA files seems to be based on nanometres rather than angstrongs
-    # like most structural biology files, so currently adjusting the world_scale to
-    # compensate
-    scale_dna = world_scale * 10
-
-    # read in the topology and trajectory files
-    is_new_top = is_new_topology(top)
-    if is_new_top:
-        topology = read_topology_new(top)
-    else:
-        topology = read_topology_old(top)
+        if style:
+            nodes.create_starting_node_tree(self.object, style="oxdna", color=None)
 
-    trajectory = read_trajectory(traj)
-    n_frames = trajectory.shape[0]
+        return self.object
 
-    # creat toplogy object with positions of the first frame, and the bonds from the
-    # topology object
-    obj = bpyd.create_object(
-        name=name,
-        collection=coll.mn(),
-        vertices=trajectory[0][:, 0:3] * scale_dna,
-        edges=toplogy_to_bond_idx_pairs(topology),
-    )
+    def _update_positions(self, frame: int) -> None:
+        super()._update_positions(frame)
+        self._update_timestep_values()
 
-    # adding additional toplogy information from the topology and frames objects
-    bpyd.store_named_attribute(
-        obj=obj, data=topology[:, 1], name="res_name", atype=AttributeTypes.INT
-    )
-    bpyd.store_named_attribute(
-        obj=obj, data=topology[:, 0], name="chain_id", atype=AttributeTypes.INT
-    )
-    bpyd.store_named_attribute(
-        obj=obj,
-        data=color.color_chains_equidistant(topology[:, 0]),
-        name="Color",
-        atype=AttributeTypes.FLOAT_COLOR,
-    )
-    store_named_attributes_to_dna_mol(obj, trajectory[0], scale_dna=scale_dna)
+    def _update_timestep_values(self):
+        for name in self._att_names:
+            try:
+                self.store_named_attribute(
+                    self.universe.trajectory.ts.data[name] * self.world_scale, name=name
+                )
+            except KeyError:
+                pass
 
-    # if the 'frames' file only contained one timepoint, return the object without creating
-    # any kind of collection for storing multiple frames from a trajectory, and a None
-    # object in place of the frames collection
-    if n_frames == 1:
-        if setup_nodes:
-            nodes.create_starting_node_tree(obj, style="oxdna", color=None)
-        return obj, None
 
-    # create a collection to store all of the frame objects that are part of the trajectory
-    # they will contain all of the possible attributes which can be interpolated betewen
-    # frames such as position, base_vector, base_normal, velocity, angular_velocity
-    collection = coll.frames(name)
-    for i, frame in enumerate(trajectory):
-        fill_n = int(np.ceil(np.log10(n_frames)))
-        frame_name = f"{name}_frame_{str(i).zfill(fill_n)}"
-        frame_obj = bpyd.create_object(
-            frame[:, 0:3] * scale_dna, name=frame_name, collection=collection
-        )
-        store_named_attributes_to_dna_mol(frame_obj, frame, scale_dna)
+def load(top, traj, name="oxDNA", style="oxdna", world_scale=0.01):
+    univ = Universe(top, traj, topology_format=OXDNAParser, format=OXDNAReader)
+    traj = OXDNA(univ, world_scale=world_scale * DNA_SCALE)
+    traj.create_object(name=name, style=style)
+    return traj
 
-    if setup_nodes:
-        nodes.create_starting_node_tree(
-            obj, coll_frames=collection, style="oxdna", color=None
-        )
 
-    return obj, collection
-
-
-class MN_OT_Import_OxDNA_Trajectory(bpy.types.Operator):
+class MN_OT_Import_OxDNA_Trajectory(TrajectoryImportOperator):
     bl_idname = "mn.import_oxdna"
-    bl_label = "Load"
-    bl_description = "Will import the given file and toplogy."
-    bl_options = {"REGISTER"}
 
     def execute(self, context):
-        s = context.scene
-        load(
-            top=s.MN_import_oxdna_topology,
-            traj=s.MN_import_oxdna_trajectory,
-            name=s.MN_import_oxdna_name,
-        )
+        load(top=self.topology, traj=self.trajectory, name=self.name)
         return {"FINISHED"}
 
 
@@ -326,8 +86,11 @@ def panel(layout, scene):
     layout.label(text="Load oxDNA File", icon="FILE_TICK")
     layout.separator()
     row = layout.row()
-    row.prop(scene, "MN_import_oxdna_name")
-    row.operator("mn.import_oxdna")
+    row.prop(scene, "import_oxdna_name")
+    op = row.operator("mn.import_oxdna")
+    op.name = scene.mn.import_oxdna_name
+    op.topology = scene.mn.import_oxdna_topology
+    op.trajectory = scene.mn.import_oxdna_trajectory
     col = layout.column(align=True)
-    col.prop(scene, "MN_import_oxdna_topology")
-    col.prop(scene, "MN_import_oxdna_trajectory")
+    col.prop(scene.mn, "import_oxdna_topology")
+    col.prop(scene.mn, "import_oxdna_trajectory")
diff --git a/molecularnodes/entities/trajectory/ops.py b/molecularnodes/entities/trajectory/ops.py
new file mode 100644
index 00000000..6ea585ee
--- /dev/null
+++ b/molecularnodes/entities/trajectory/ops.py
@@ -0,0 +1,35 @@
+from bpy.types import Operator
+from bpy.props import StringProperty, BoolProperty, EnumProperty
+
+from ...style import STYLE_ITEMS
+
+
+class TrajectoryImportOperator(Operator):
+    bl_label = "Import"
+    bl_description = "Will import the given file and toplogy."
+    bl_options = {"REGISTER"}
+
+    topology: StringProperty(  # type: ignore
+        name="Toplogy",
+        description="File path for the topology file",
+        subtype="FILE_PATH",
+        maxlen=0,
+    )
+    trajectory: StringProperty(  # type: ignore
+        name="Trajectory",
+        description="File path for the trajectory file",
+        subtype="FILE_PATH",
+        maxlen=0,
+    )
+    name: StringProperty(  # type: ignore
+        name="Name",
+        description="Name for the object that will be created and linked to the trajectory",
+        default="NewOrigami",
+        maxlen=0,
+    )
+    style: EnumProperty(  # type: ignore
+        name="Style",
+        description="Starting style on import",
+        default="spheres",
+        items=STYLE_ITEMS,
+    )
diff --git a/molecularnodes/entities/trajectory/oxdna/OXDNAParser.py b/molecularnodes/entities/trajectory/oxdna/OXDNAParser.py
new file mode 100644
index 00000000..fbc091bf
--- /dev/null
+++ b/molecularnodes/entities/trajectory/oxdna/OXDNAParser.py
@@ -0,0 +1,134 @@
+import numpy as np
+from MDAnalysis.topology.base import TopologyReaderBase
+from MDAnalysis.core.topology import Topology
+from MDAnalysis.core.topologyattrs import (
+    Atomids,
+    Bonds,
+    ChainIDs,
+    Resids,
+    Resnames,
+    Resnums,
+)
+
+
+class OXDNAParser(TopologyReaderBase):
+    def parse(self, **kwargs):
+        top = self._parseatoms()
+
+        return top
+
+    @classmethod
+    def _is_new_topology(self, filename) -> bool:
+        with open(filename) as f:
+            return "5->3" in f.readline()
+
+    @classmethod
+    def _read_topo_new(cls, filename) -> Topology:
+        with open(filename) as f:
+            lines = f.readlines()
+        n_atoms, n_chains, direction = np.array(lines[0].split())
+        n_atoms = int(n_atoms)
+        atom_idx = np.arange(n_atoms)
+
+        res_name_list = []
+        chain_id_list = []
+        for i, line in enumerate(lines[1:]):
+            is_rna = "type=RNA" in line
+            is_dna = not is_rna
+
+            line_split = line.split()
+            bases = line_split[0]
+
+            base_list = []
+            start = 0
+            end = 0
+            in_custom_base = False
+            for i, letter in enumerate(bases):
+                if letter == "(":
+                    start = i + 1
+                    in_custom_base = True
+                    continue
+                if letter == ")":
+                    end = i
+                    base_list.append(line[start:end])
+                    in_custom_base = False
+                    continue
+
+                if in_custom_base:
+                    continue
+
+                base_list.append(letter)
+            chain_id_list.append(np.repeat(i, len(base_list)))
+
+            res_name_list.append(np.array(base_list))
+
+        res_names = np.hstack(res_name_list)
+        chain_ids = np.hstack(chain_id_list)
+
+        bond_idx = np.zeros((n_atoms, 2), dtype=int)
+        bond_idx[:, :] = -1
+
+        for i in atom_idx:
+            if i == 1:
+                continue
+            if chain_ids[i] == chain_ids[-1]:
+                bond_idx[i, :] = np.array((i, i - 1), dtype=int)
+
+        mask = np.logical_and(bond_idx[:, 0] != -1, bond_idx[:, 1] != -1)
+        bond_idx = bond_idx[mask, :]
+
+        attrs = []
+        for Attr in (Atomids, Resnums, Resids):
+            attrs.append(Attr(atom_idx))
+
+        attrs.append(ChainIDs(chain_ids))
+        attrs.append(Resnames(res_names))
+
+        topo = Topology(n_atoms, n_atoms, 1, attrs=attrs)
+        bonds = Bonds(bond_idx)
+        topo.add_TopologyAttr(bonds)
+
+        return topo
+
+    @classmethod
+    def _read_topo_old(cls, filename) -> Topology:
+        with open(filename) as f:
+            first_line = f.readline()
+
+        dimensions = np.array(first_line.split())
+        n_atoms = int(dimensions[0])
+        array = np.loadtxt(filename, skiprows=1, max_rows=n_atoms, dtype=str)
+
+        # each topology item has two bond columns, which say what the base is bonded
+        # from and what it is bonded to. -1 means it is not bonded
+        # we need to turn that into an array of bond pairs
+        bond_idx = np.zeros((n_atoms * 2, 2), int)
+        row_numbers = np.arange(n_atoms, dtype=int)
+        for i in range(2):
+            rows = row_numbers + (i * n_atoms)
+            bond_idx[rows, 0] = array[:, (i + 2)]
+            bond_idx[rows, 1] = row_numbers
+
+        # drop any that have -1 as they aren't bonded to anything
+        mask = np.logical_and(bond_idx[:, 0] != -1, bond_idx[:, 1] != -1)
+        bond_idx = bond_idx[mask, :]
+
+        attrs = []
+        idx = np.arange(1, n_atoms + 1, dtype=int)
+        for Attr in (Atomids, Resnums, Resids):
+            attrs.append(Attr(idx))
+        attrs.append(ChainIDs(array[:, 0].astype(int)))
+        attrs.append(Resnames(array[:, 1].astype(str)))
+
+        topo = Topology(n_atoms, n_atoms, 1, attrs=attrs)
+
+        bonds = Bonds(bond_idx)
+        topo.add_TopologyAttr(bonds)
+
+        return topo
+
+    def _parseatoms(self):
+        if self._is_new_topology(self.filename):
+            return self._read_topo_new(self.filename)
+        else:
+            return self._read_topo_old(self.filename)
diff --git a/molecularnodes/entities/trajectory/oxdna/OXDNAReader.py b/molecularnodes/entities/trajectory/oxdna/OXDNAReader.py
new file mode 100644
index 00000000..81c1ec3a
--- /dev/null
+++ b/molecularnodes/entities/trajectory/oxdna/OXDNAReader.py
@@ -0,0 +1,90 @@
+import numpy as np
+
+from MDAnalysis.coordinates.base import ReaderBase
+from MDAnalysis.lib import util
+
+
+def _is_info_line(line: str):
+    return line.startswith("t = ") or line.startswith("b = ") or line.startswith("E = ")
+
+
+class OXDNAReader(ReaderBase):
+    def __init__(self, filename, **kwargs):
+        super(OXDNAReader, self).__init__(filename, **kwargs)
+
+        self.n_atoms = kwargs["n_atoms"]
+        self.ts = self._Timestep(self.n_atoms, **self._ts_kwargs)
+
+        oxdnafile = self._oxdnafile = util.anyopen(filename, "rb")
+
+        starts = []
+        stops = []
+
+        line = "a new line"
+        previous_is_info = False
+        current_is_info = False
+        while line:
+            line = oxdnafile.readline().decode()
+            current_is_info = _is_info_line(line)
+
+            # get the lines where the data values start and stop, which
+            # are separated by the several lines of overall information
+            if not current_is_info and previous_is_info:
+                starts.append(oxdnafile.tell() - len(line))
+            if current_is_info and not previous_is_info:
+                stops.append(oxdnafile.tell() - len(line))
+
+            previous_is_info = current_is_info
+
+        # add the end of the file
+        stops += [oxdnafile.tell()]
+
+        self._start_offsets = starts
+        self._stop_offsets = stops[1:]  # drop the first
+        self.n_frames = len(self._start_offsets)
+
+        self._read_frame(0)
+
+    def _reopen(self):
+        self.close()
+        self._oxdnafile = util.anyopen(self.filename, "rb")
+        self.ts.frame = -1
+
+    def _read_next_timestep(self, ts=None):
+        frame = self.frame + 1
+        return self._read_frame(frame)
+
+    def _read_frame(self, frame):
+        try:
+            start = self._start_offsets[frame]
+            stop = self._stop_offsets[frame]
+        except IndexError:
+            raise OSError from None
+
+        self._oxdnafile.seek(start)
+        chunk = self._oxdnafile.read(stop - start)
+
+        array = np.array(
+            [
+                np.array(line.split(), dtype=float)
+                for line in chunk.decode().splitlines()
+            ]
+        )
+
+        # TODO: also access and update the other values
+        self.ts.positions = array[:, :3]
+
+        for i, name in enumerate(
+            ("base_vector", "base_normal", "velocity", "angular_velocity")
+        ):
+            starting_column = 3 * (i + 1)
+            if starting_column >= array.shape[1]:
+                continue
+            cols = np.arange(3) + starting_column
+            self.ts.data[name] = array[:, cols]
+        self.ts.frame = frame
+
+        return self.ts
+
+    def close(self):
+        self._oxdnafile.close()
diff --git a/molecularnodes/entities/trajectory/props.py b/molecularnodes/entities/trajectory/props.py
new file mode 100644
index 00000000..2333042e
--- /dev/null
+++ b/molecularnodes/entities/trajectory/props.py
@@ -0,0 +1,119 @@
+import bpy
+from bpy.props import StringProperty, BoolProperty
+from ...handlers import _selection_update_trajectories, _update_trajectories
+
+
+class TrajectorySelectionItem(bpy.types.PropertyGroup):
+    """Group of properties for custom selections for MDAnalysis import."""
+
+    name: StringProperty(  # type: ignore
+        name="Name",
+        description="Name of the attribute on the mesh",
+        default="custom_selection",
+        update=_selection_update_trajectories,
+    )
+
+    selection_str: StringProperty(  # type: ignore
+        name="Selection",
+        description="Selection to be applied, written in the MDAnalysis selection language",
+        default="name CA",
+        update=_selection_update_trajectories,
+    )
+
+    updating: BoolProperty(  # type: ignore
+        name="Updating",
+        description="Recalculate the selection on scene frame change",
+        default=True,
+        update=_selection_update_trajectories,
+    )
+
+    periodic: BoolProperty(  # type: ignore
+        name="Periodic",
+        description="For geometric selections, whether to account for atoms in different periodic images when searching",
+        default=True,
+        update=_selection_update_trajectories,
+    )
+
+    message: StringProperty(  # type: ignore
+        name="Message",
+        description="Message to report back from `universe.select_atoms()`",
+        default="",
+    )
+
+    immutable: BoolProperty(  # type: ignore
+        name="Immutable",
+        description="Whether the selection is immutable",
+        default=False,
+    )
+
+
+class MN_UL_TrajectorySelectionListUI(bpy.types.UIList):
+    """UI List"""
+
+    def draw_item(
+        self, context, layout, data, item, icon, active_data, active_propname, index
+    ):
+        custom_icon = "VIS_SEL_11"
+
+        if self.layout_type in {"DEFAULT", "COMPACT"}:
+            row = layout.row()
+            if item.message != "":
+                custom_icon = "ERROR"
+                row.alert = True
+
+            row.prop(item, "name", text="", emboss=False)
+            row.prop(item, "updating", icon_only=True, icon="FILE_REFRESH")
+            row.prop(item, "periodic", icon_only=True, icon="CUBE")
+            if item.immutable:
+                row.enabled = False
+
+        elif self.layout_type in {"GRID"}:
+            layout.alignment = "CENTER"
+            layout.label(text="", icon=custom_icon)
+
+
+class MN_OT_Universe_Selection_Add(bpy.types.Operator):
+    "Add a new custom selection to a trajectory"
+
+    bl_idname = "mn.trajectory_selection_add"
+    bl_label = "+"
+    bl_description = "Add a new boolean attribute for the given MDA selection string"
+
+    def execute(self, context):
+        obj = context.active_object
+        obj.mn_trajectory_selections.add()
+        i = int(len(obj.mn_trajectory_selections) - 1)
+        obj.mn_trajectory_selections[i].name = f"selection_{i + 1}"
+        obj.mn["list_index"] = i
+        _update_trajectories(self, context)
+
+        return {"FINISHED"}
+
+
+class MN_OT_Universe_Selection_Delete(bpy.types.Operator):
+    bl_idname = "mda.delete_item"
+    bl_label = "-"
+    bl_description = "Delete the given boolean selection from the universe"
+
+    @classmethod
+    def poll(cls, context):
+        return context.active_object.mn_trajectory_selections
+
+    def execute(self, context):
+        obj = context.active_object
+        index = obj.mn.trajectory_selection_index
+
+        sel_list = obj.mn_trajectory_selections
+        sel_list.remove(index)
+        obj.mn.trajectory_selection_index = len(sel_list) - 1
+        _update_trajectories(self, context)
+
+        return {"FINISHED"}
+
+
+CLASSSES = [
+    TrajectorySelectionItem,  # has to be registered before the others to work properly
+    MN_UL_TrajectorySelectionListUI,
+    MN_OT_Universe_Selection_Add,
+    MN_OT_Universe_Selection_Delete,
+]
diff --git a/molecularnodes/entities/trajectory/selections.py b/molecularnodes/entities/trajectory/selections.py
index 50f94da3..6af069e3 100644
--- a/molecularnodes/entities/trajectory/selections.py
+++ b/molecularnodes/entities/trajectory/selections.py
@@ -1,9 +1,6 @@
-import bpy
 import MDAnalysis as mda
 import numpy.typing as npt
 import numpy as np
-from bpy.props import StringProperty, BoolProperty
-from .handlers import _selection_update_trajectories, _update_trajectories
 
 
 class Selection:
@@ -83,119 +80,3 @@ def from_atomgroup(cls, atomgroup: mda.AtomGroup, name: str = ""):
         selection.ag = atomgroup
         selection.mask_array = selection._ag_to_mask()
         return selection
-
-
-class TrajectorySelectionItem(bpy.types.PropertyGroup):
-    """Group of properties for custom selections for MDAnalysis import."""
-
-    name: StringProperty(  # type: ignore
-        name="Name",
-        description="Name of the attribute on the mesh",
-        default="custom_selection",
-        update=_selection_update_trajectories,
-    )
-
-    selection_str: StringProperty(  # type: ignore
-        name="Selection",
-        description="Selection to be applied, written in the MDAnalysis selection language",
-        default="name CA",
-        update=_selection_update_trajectories,
-    )
-
-    updating: BoolProperty(  # type: ignore
-        name="Updating",
-        description="Recalculate the selection on scene frame change",
-        default=True,
-        update=_selection_update_trajectories,
-    )
-
-    periodic: BoolProperty(  # type: ignore
-        name="Periodic",
-        description="For geometric selections, whether to account for atoms in different periodic images when searching",
-        default=True,
-        update=_selection_update_trajectories,
-    )
-
-    message: StringProperty(  # type: ignore
-        name="Message",
-        description="Message to report back from `universe.select_atoms()`",
-        default="",
-    )
-
-    immutable: BoolProperty(  # type: ignore
-        name="Immutable",
-        description="Whether the selection is immutable",
-        default=False,
-    )
-
-
-class MN_UL_TrajectorySelectionListUI(bpy.types.UIList):
-    """UI List"""
-
-    def draw_item(
-        self, context, layout, data, item, icon, active_data, active_propname, index
-    ):
-        custom_icon = "VIS_SEL_11"
-
-        if self.layout_type in {"DEFAULT", "COMPACT"}:
-            row = layout.row()
-            if item.message != "":
-                custom_icon = "ERROR"
-                row.alert = True
-
-            row.prop(item, "name", text="", emboss=False)
-            row.prop(item, "updating", icon_only=True, icon="FILE_REFRESH")
-            row.prop(item, "periodic", icon_only=True, icon="CUBE")
-            if item.immutable:
-                row.enabled = False
-
-        elif self.layout_type in {"GRID"}:
-            layout.alignment = "CENTER"
-            layout.label(text="", icon=custom_icon)
-
-
-class MN_OT_Universe_Selection_Add(bpy.types.Operator):
-    "Add a new custom selection to a trajectory"
-
-    bl_idname = "mn.trajectory_selection_add"
-    bl_label = "+"
-    bl_description = "Add a new boolean attribute for the given MDA selection string"
-
-    def execute(self, context):
-        obj = context.active_object
-        obj.mn_trajectory_selections.add()
-        i = int(len(obj.mn_trajectory_selections) - 1)
-        obj.mn_trajectory_selections[i].name = f"selection_{i + 1}"
-        obj.mn["list_index"] = i
-        _update_trajectories(self, context)
-
-        return {"FINISHED"}
-
-
-class MN_OT_Universe_Selection_Delete(bpy.types.Operator):
-    bl_idname = "mda.delete_item"
-    bl_label = "-"
-    bl_description = "Delete the given boolean selection from the universe"
-
-    @classmethod
-    def poll(cls, context):
-        return context.active_object.mn_trajectory_selections
-
-    def execute(self, context):
-        obj = context.active_object
-        index = obj.mn.trajectory_selection_index
-
-        sel_list = obj.mn_trajectory_selections
-        sel_list.remove(index)
-        obj.mn.trajectory_selection_index = len(sel_list) - 1
-        _update_trajectories(self, context)
-
-        return {"FINISHED"}
-
-
-CLASSSES = [
-    TrajectorySelectionItem,  # has to be registered before the others to work properly
-    MN_UL_TrajectorySelectionListUI,
-    MN_OT_Universe_Selection_Add,
-    MN_OT_Universe_Selection_Delete,
-]
diff --git a/molecularnodes/entities/trajectory/trajectory.py b/molecularnodes/entities/trajectory/trajectory.py
index 5186fd84..10565736 100644
--- a/molecularnodes/entities/trajectory/trajectory.py
+++ b/molecularnodes/entities/trajectory/trajectory.py
@@ -16,7 +16,7 @@
     frames_to_average,
     fraction,
 )
-from .selections import Selection, TrajectorySelectionItem
+from .selections import Selection
 
 
 class Trajectory(MolecularEntity):
@@ -30,7 +30,7 @@ def __init__(self, universe: mda.Universe, world_scale: float = 0.01):
         self.cache: dict = {}
         bpy.context.scene.MNSession.trajectories[self.uuid] = self
 
-    def selection_from_ui(self, ui_item: TrajectorySelectionItem) -> Selection:
+    def selection_from_ui(self, ui_item) -> Selection:
         self.selections[ui_item.name] = Selection(
             universe=self.universe,
             selection_str=ui_item.selection_str,
@@ -48,7 +48,7 @@ def add_selection(
         name: str,
         updating: bool = True,
         periodic: bool = True,
-    ) -> TrajectorySelectionItem:
+    ):
         "Adds a new selection with the given name, selection string and selection parameters."
         obj = self.object
 
@@ -209,6 +209,10 @@ def uframe(self, value) -> None:
     def res_name(self) -> np.ndarray:
         return np.array(list(map(lambda x: x[0:3], self.atoms.resnames)))
 
+    @property
+    def atom_id(self) -> np.ndarray:
+        return self.universe.atoms.atom_id
+
     @property
     def res_num(self) -> np.ndarray:
         return np.array(
@@ -258,10 +262,13 @@ def atom_type_unique(self) -> np.ndarray:
 
     @property
     def atom_type_num(self) -> np.ndarray:
-        atom_type_unique, atom_type_index = np.unique(
-            self.atom_type, return_inverse=True
-        )
-        return atom_type_index
+        try:
+            atom_type_unique, atom_type_index = np.unique(
+                self.atom_type, return_inverse=True
+            )
+            return atom_type_index
+        except AttributeError:
+            return None
 
     @property
     def atom_name(self) -> np.ndarray:
@@ -400,13 +407,9 @@ def save_filepaths_on_object(self) -> None:
             path_resolve(self.universe.trajectory.filename)
         )
 
-    def create_object(
-        self,
-        style: str = "vdw",
-        name: str = "NewUniverseObject",
-        subframes: int = 0,
-        # in_memory: bool = False,
-    ):
+    def _create_object(
+        self, style: str = "vdw", name: str = "NewUniverseObject"
+    ) -> bpy.types.Object:
         obj = bpyd.create_object(
             name=name,
             collection=coll.mn(),
@@ -432,20 +435,20 @@ def create_object(
                 segs.append(seg.atoms[0].segid)
 
             obj["segments"] = segs
-
-        obj["chain_ids"] = self.chain_ids
-        obj["atom_type_unique"] = self.atom_type_unique
-        self.subframes = subframes
-        obj.mn.molecule_type = "md"
-        self.save_filepaths_on_object()
-
         if style is not None:
             nodes.create_starting_node_tree(obj, style=style, name=f"MN_{obj.name}")
 
-        bpy.context.view_layer.objects.active = obj
-        obj.mn.uuid = self.uuid
+    def create_object(self, style: str = "vdw", name: str = "NewUniverseObject"):
+        self._create_object(style=style, name=name)
+        self.object.mn.uuid = self.uuid
+        self.object["chain_ids"] = self.chain_ids
+        if hasattr(self, "atom_type_unique"):
+            self.object["atom_type_unique"] = self.atom_type_unique
+        self.object.mn.molecule_type = "md"
+        self.save_filepaths_on_object()
+        bpy.context.view_layer.objects.active = self.object
 
-        return obj
+        return self.object
 
     def _update_calculations(self):
         for name, func in self.calculations.items():
diff --git a/molecularnodes/entities/trajectory/ui.py b/molecularnodes/entities/trajectory/ui.py
index bc69e1ba..0e819739 100644
--- a/molecularnodes/entities/trajectory/ui.py
+++ b/molecularnodes/entities/trajectory/ui.py
@@ -9,7 +9,6 @@
 import MDAnalysis as mda
 
 from ... import blender as bl
-from ...session import get_session
 from .trajectory import Trajectory
 from bpy.props import StringProperty
 
@@ -33,13 +32,7 @@
 )
 
 
-def load(
-    top,
-    traj,
-    name="NewTrajectory",
-    style="spheres",
-    subframes: int = 0,
-):
+def load(top, traj, name="NewTrajectory", style="spheres"):
     top = bl.path_resolve(top)
     traj = bl.path_resolve(traj)
 
@@ -47,7 +40,7 @@ def load(
 
     traj = Trajectory(universe=universe)
 
-    traj.create_object(name=name, style=style, subframes=subframes)
+    traj.create_object(name=name, style=style)
 
     return traj
 
@@ -63,7 +56,7 @@ class MN_OT_Reload_Trajectory(bpy.types.Operator):
     @classmethod
     def poll(cls, context):
         obj = context.active_object
-        traj = get_session(context).trajectories.get(obj.mn.uuid)
+        traj = context.scene.MNSession.trajectories.get(obj.mn.uuid)
         return not traj
 
     def execute(self, context):
@@ -91,7 +84,7 @@ def execute(self, context):
             top=topology_file,
             traj=trajectory_file,
             name=name,
-            style=scene.MN_import_style,
+            style=scene.mn.import_style,
         )
 
         context.view_layer.objects.active = trajectory.object
@@ -127,7 +120,7 @@ def panel(layout, scene):
     row = layout.row()
     row.prop(scene, "MN_import_node_setup", text="")
     col = row.column()
-    col.prop(scene, "MN_import_style")
+    col.prop(scene.mn, "import_style")
     col.enabled = scene.MN_import_node_setup
 
 
diff --git a/molecularnodes/entities/trajectory/handlers.py b/molecularnodes/handlers.py
similarity index 93%
rename from molecularnodes/entities/trajectory/handlers.py
rename to molecularnodes/handlers.py
index 8e1ef63e..51e3fc29 100644
--- a/molecularnodes/entities/trajectory/handlers.py
+++ b/molecularnodes/handlers.py
@@ -1,6 +1,8 @@
 import bpy
 from bpy.app.handlers import persistent
 
+# from .session import MNSession
+
 
 # this update function requires a self and context input, as funcitons with these inputs
 # have ot be passed to the `update` arguments of UI properties. When the UI is updated,
@@ -34,7 +36,8 @@ def _selection_update_trajectories(self, context: bpy.types.Context) -> None:
 @persistent
 def update_trajectories(scene):
     "Updatins all positions and selections for each trajectory."
-    for trajectory in scene.MNSession.trajectories.values():
+    session: MNSession = scene.MNSession
+    for trajectory in session.trajectories.values():
         try:
             trajectory._update_positions(scene.frame_current)
             trajectory._update_selections()
diff --git a/molecularnodes/props.py b/molecularnodes/props.py
index 59139694..052bc78f 100644
--- a/molecularnodes/props.py
+++ b/molecularnodes/props.py
@@ -1,6 +1,9 @@
 import bpy
+from bpy.types import PropertyGroup
 from bpy.props import IntProperty, BoolProperty, EnumProperty, StringProperty
-from .entities.trajectory.handlers import _update_trajectories
+from .handlers import _update_trajectories
+from .style import STYLE_ITEMS
+
 
 bpy.types.Scene.MN_import_centre = BoolProperty(
     name="Centre Structure",
@@ -48,7 +51,29 @@
 )
 
 
-class MolecularNodesObjectProperties(bpy.types.PropertyGroup):
+class MolecularNodesSceneProperties(PropertyGroup):
+    import_oxdna_topology: StringProperty(  # type: ignore
+        name="Toplogy",
+        description="File path for the topology to import (.top)",
+        subtype="FILE_PATH",
+    )
+    import_oxdna_trajectory: StringProperty(  # type: ignore
+        name="Trajectory",
+        description="File path for the trajectory to import (.oxdna / .dat)",
+        subtype="FILE_PATH",
+    )
+    import_oxdna_name: StringProperty(  # type: ignore
+        name="Name", description="Name of the created object.", default="NewOrigami"
+    )
+    import_style: EnumProperty(  # type: ignore
+        name="Style",
+        description="Default style for importing",
+        items=STYLE_ITEMS,
+        default="spheres",
+    )
+
+
+class MolecularNodesObjectProperties(PropertyGroup):
     molecule_type: StringProperty(  # type: ignore
         name="Molecular Type",
         description="How the file was imported, dictating how MN interacts with it",
@@ -115,3 +140,6 @@ class MolecularNodesObjectProperties(bpy.types.PropertyGroup):
         subtype="FILE_PATH",
         default="",
     )
+
+
+CLASSES = [MolecularNodesObjectProperties, MolecularNodesSceneProperties]
diff --git a/molecularnodes/style.py b/molecularnodes/style.py
new file mode 100644
index 00000000..3d98752c
--- /dev/null
+++ b/molecularnodes/style.py
@@ -0,0 +1,12 @@
+STYLE_ITEMS = (
+    ("spheres", "Spheres", "Space-filling atoms style."),
+    ("cartoon", "Cartoon", "Secondary structure cartoons"),
+    ("surface", "Surface", "Solvent-accsible surface."),
+    ("ribbon", "Ribbon", "Continuous backbone ribbon."),
+    ("sticks", "Sticks", "Sticks for each bond."),
+    ("ball_and_stick", "Ball and Stick", "Spheres for atoms, sticks for bonds"),
+    ("preset_1", "Preset 1", "A pre-made combination of different styles"),
+    ("preset_2", "Preset 2", "A pre-made combination of different styles"),
+    ("preset_3", "Preset 3", "A pre-made combination of different styles"),
+    ("preset_4", "Preset 4", "A pre-made combination of different styles"),
+)
diff --git a/molecularnodes/ui/__init__.py b/molecularnodes/ui/__init__.py
index ac676ffd..dcf93ca0 100644
--- a/molecularnodes/ui/__init__.py
+++ b/molecularnodes/ui/__init__.py
@@ -1,3 +1,4 @@
-from . import panel, node_menu
+from .panel import CLASSES as PANEL_CLASSES
+from .node_menu import CLASSES as NODE_MENU_CLASSES
 
-CLASSES = panel.CLASSES + node_menu.CLASSES
+CLASSES = PANEL_CLASSES + NODE_MENU_CLASSES
diff --git a/molecularnodes/ui/panel.py b/molecularnodes/ui/panel.py
index 27ee50af..4dcdcb28 100644
--- a/molecularnodes/ui/panel.py
+++ b/molecularnodes/ui/panel.py
@@ -33,25 +33,7 @@
         ("dna", "oxDNA", "Import an oxDNA file"),
     ),
 )
-STYLE_ITEMS = (
-    ("spheres", "Spheres", "Space-filling atoms style."),
-    ("cartoon", "Cartoon", "Secondary structure cartoons"),
-    ("surface", "Surface", "Solvent-accsible surface."),
-    ("ribbon", "Ribbon", "Continuous backbone ribbon."),
-    ("sticks", "Sticks", "Sticks for each bond."),
-    ("ball_and_stick", "Ball and Stick", "Spheres for atoms, sticks for bonds"),
-    ("preset_1", "Preset 1", "A pre-made combination of different styles"),
-    ("preset_2", "Preset 2", "A pre-made combination of different styles"),
-    ("preset_3", "Preset 3", "A pre-made combination of different styles"),
-    ("preset_4", "Preset 4", "A pre-made combination of different styles"),
-)
 
-bpy.types.Scene.MN_import_style = bpy.props.EnumProperty(
-    name="Style",
-    description="Default style for importing molecules.",
-    items=STYLE_ITEMS,
-    default="spheres",
-)
 
 chosen_panel = {
     "pdb": molecule.ui.panel_wwpdb,
@@ -64,17 +46,6 @@
     "dna": dna.panel,
 }
 
-packages = {
-    "pdb": ["biotite"],
-    "alphafold": ["biotite"],
-    "star": ["starfile", "mrcfile", "pillow"],
-    "local": ["biotite"],
-    "cellpack": ["biotite", "msgpack"],
-    "md": ["MDAnalysis"],
-    "density": ["mrcfile"],
-    "dna": [],
-}
-
 
 def pt_object_context(self, context):
     layout = self.layout
diff --git a/tests/__snapshots__/test_dna.ambr b/tests/__snapshots__/test_dna.ambr
index 0c7b6ab1..cc245c3a 100644
--- a/tests/__snapshots__/test_dna.ambr
+++ b/tests/__snapshots__/test_dna.ambr
@@ -1,1511 +1,379 @@
 # serializer version: 1
-# name: test_read_oxdna
-  [32 33 30 31 31 31 32 31 31 30 30 31 30 33 33 32 33 31 32 33 31 30 33 31
-   30 32 33 32 33 32 33 32 31 32 32 32 30 33 30 31 31 32 32 33 30 30 31 30
-   31 33 33 31 31 31 33 31 30 31 32 30 31 32 33 31 32 33 31 31 33 32 31 32
-   32 32 33 33 31 30 30 31 33 30 32 32 30 33 33 32 31 30 33 33 32 33 31 31
-   33 33 30 30]
+# name: TestOXDNAReading.test_comparing_topologies[top_new]
+  list([
+    list([
+      1,
+      2,
+    ]),
+    list([
+      2,
+      3,
+    ]),
+    list([
+      3,
+      4,
+    ]),
+    list([
+      4,
+      5,
+    ]),
+    list([
+      5,
+      6,
+    ]),
+    list([
+      6,
+      7,
+    ]),
+    list([
+      7,
+      8,
+    ]),
+    list([
+      8,
+      9,
+    ]),
+    list([
+      9,
+      10,
+    ]),
+    list([
+      10,
+      11,
+    ]),
+  ])
 # ---
-# name: test_read_oxdna.1
-  [4 1 4 3 1 1 2 4 3 3 1 3 4 2 3 4 4 1 2 4 3 1 3 3 1 3 3 2 3 4 2 3 1 1 2 3 4
-   2 4 4 1 4 2 3 3 3 1 1 4 4 2 1 3 3 2 3 4 2 2 2 1 2 2 1 3 3 3 3 3 3 1 4 1 2
-   3 3 1 4 2 1 3 4 1 4 3 4 3 4 4 4 3 3 2 4 1 3 2 2 2 3]
+# name: TestOXDNAReading.test_comparing_topologies[top_new].1
+  list([
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+  ])
 # ---
-# name: test_read_oxdna.10
-  [ True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True]
+# name: TestOXDNAReading.test_comparing_topologies[top_new].2
+  list([
+    5.0,
+    5.0,
+    5.0,
+    5.0,
+    5.0,
+    5.0,
+    5.0,
+    5.0,
+    5.0,
+    5.0,
+    5.0,
+    5.0,
+  ])
 # ---
-# name: test_read_oxdna.11
-  AttributeError("The selected attribute 'sharp_face' does not exist on the mesh.")
+# name: TestOXDNAReading.test_comparing_topologies[top_new].3
+  list([
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+  ])
 # ---
-# name: test_read_oxdna.12
-  [32 32 30 30 31 31 33 31 31 30 33 32 32 33 31 30 33 30 31 31 31 33 31 30
-   32 31 32 33 33 32 33 33 32 30 33 31 31 33 30 31 30 31 33 32 32 32 33 30
-   31 31 31 32 32 33 33 33 32 30 32 33 31 32 30 31 31 32 33 31 32 33 31 31
-   32 31 30 33 30 32 31 32 33 32 31 33 33 30 33 32 33 33 32 30 31 32 32 33
-   32 31 31 33]
+# name: TestOXDNAReading.test_comparing_topologies[top_new_custom]
+  list([
+    list([
+      5,
+      6,
+    ]),
+    list([
+      6,
+      7,
+    ]),
+    list([
+      7,
+      8,
+    ]),
+    list([
+      8,
+      9,
+    ]),
+    list([
+      9,
+      10,
+    ]),
+    list([
+      10,
+      11,
+    ]),
+  ])
 # ---
-# name: test_read_oxdna.13
-  [3 4 3 2 1 1 3 1 4 1 3 4 2 2 3 2 3 3 3 1 3 1 2 3 3 3 2 3 3 2 2 1 4 2 4 4 1
-   1 3 3 4 1 4 3 4 4 2 4 3 4 2 2 4 2 4 2 4 1 2 1 1 4 4 1 1 2 3 4 4 2 1 3 2 3
-   3 3 3 3 3 2 3 4 3 3 4 2 3 2 3 3 4 1 1 4 3 1 2 3 4 3]
+# name: TestOXDNAReading.test_comparing_topologies[top_new_custom].1
+  list([
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+    0,
+  ])
 # ---
-# name: test_read_oxdna.14
-  [[0.4 0.8 0.5 0.0]
-   [0.8 0.2 0.2 1.0]
-   [0.4 0.8 0.5 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.8 0.3 0.5 1.0]
-   [0.3 0.8 0.2 1.0]
-   [0.4 0.5 0.8 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.2 0.2 1.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.3 0.5 1.0]
-   [0.4 0.8 0.5 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.3 0.8 0.2 1.0]
-   [0.3 0.8 0.2 1.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.3 0.5 1.0]
-   [0.3 0.8 0.2 1.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.2 0.2 1.0]
-   [0.4 0.8 0.5 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.3 0.5 1.0]
-   [0.8 0.2 0.2 1.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.3 0.5 1.0]
-   [0.3 0.8 0.2 1.0]
-   [0.8 0.4 0.4 0.0]
-   [0.8 0.3 0.5 1.0]
-   [0.4 0.8 0.5 0.0]
-   [0.3 0.8 0.2 1.0]
-   [0.4 0.5 0.8 0.0]
-   [0.3 0.8 0.2 1.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.2 0.2 1.0]
-   [0.8 0.2 0.2 1.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.2 0.2 1.0]
-   [0.8 0.2 0.2 1.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.2 0.2 1.0]
-   [0.8 0.4 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.3 0.8 0.2 1.0]
-   [0.3 0.8 0.2 1.0]
-   [0.8 0.2 0.2 1.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.8 0.2 0.2 1.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.3 0.8 0.2 1.0]
-   [0.8 0.2 0.2 1.0]
-   [0.4 0.8 0.5 0.0]
-   [0.3 0.5 0.8 1.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.2 0.2 1.0]
-   [0.3 0.8 0.2 1.0]
-   [0.8 0.2 0.2 1.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.2 0.2 1.0]
-   [0.3 0.8 0.2 1.0]
-   [0.8 0.3 0.5 1.0]
-   [0.4 0.5 0.8 0.0]
-   [0.3 0.5 0.8 1.0]
-   [0.4 0.8 0.5 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.3 0.5 1.0]
-   [0.8 0.2 0.2 1.0]
-   [0.8 0.4 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.3 0.5 1.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.3 0.8 0.2 1.0]
-   [0.8 0.3 0.5 1.0]]
+# name: TestOXDNAReading.test_comparing_topologies[top_new_custom].2
+  list([
+    8.0,
+    8.0,
+    8.0,
+    8.0,
+    8.0,
+    8.0,
+    9.0,
+    9.0,
+    9.0,
+    9.0,
+    9.0,
+    9.0,
+  ])
 # ---
-# name: test_read_oxdna.15
-  [[-0.3  0.5  0.1]
-   [-0.0  0.8 -0.1]
-   [-0.1  0.7  0.1]
-   [ 0.1  0.3  0.1]
-   [-0.3  0.3  0.6]
-   [-0.3  0.4  0.6]
-   [-0.1  0.8 -0.3]
-   [ 0.1  0.5  0.1]
-   [-0.2  0.4  0.3]
-   [-0.0  0.3 -0.0]
-   [-0.1  0.8 -0.2]
-   [-0.1  0.8 -0.0]
-   [ 0.0  0.4  0.2]
-   [-0.5  0.2  0.1]
-   [-0.1  0.7 -0.1]
-   [ 0.1  0.3  0.0]
-   [-0.1  0.7  0.0]
-   [-0.1  0.7  0.1]
-   [-0.5  0.2  0.1]
-   [-0.2  0.4  0.6]
-   [-0.0  0.6 -0.1]
-   [-0.1  0.3  0.1]
-   [-0.4  0.2  0.1]
-   [-0.2  0.3  0.1]
-   [-0.2  0.5  0.1]
-   [-0.1  0.7 -0.1]
-   [ 0.0  0.3  0.1]
-   [-0.1  0.9 -0.2]
-   [-0.1  0.8 -0.2]
-   [-0.1  0.4 -0.0]
-   [-0.1  0.4  0.1]
-   [-0.1  0.3  0.0]
-   [-0.1  0.8 -0.1]
-   [ 0.1  0.3  0.1]
-   [-0.2  0.4  0.4]
-   [-0.1  0.5  0.2]
-   [ 0.1  0.5  0.1]
-   [-0.1  0.3  0.0]
-   [-0.3  0.4 -0.0]
-   [-0.4  0.2 -0.0]
-   [-0.2  0.6  0.0]
-   [-0.2  0.3  0.0]
-   [-0.1  0.6 -0.0]
-   [-0.1  0.7  0.1]
-   [-0.1  0.6  0.1]
-   [-0.2  0.4  0.6]
-   [-0.0  0.4  0.1]
-   [-0.2  0.7 -0.1]
-   [-0.1  0.6 -0.1]
-   [-0.1  0.5  0.2]
-   [ 0.1  0.3  0.1]
-   [ 0.2  0.5  0.0]
-   [-0.1  0.8 -0.1]
-   [-0.5  0.3  0.0]
-   [-0.1  0.4  0.5]
-   [-0.2  0.3 -0.1]
-   [-0.2  0.3  0.5]
-   [-0.1  0.4  0.3]
-   [ 0.2  0.4  0.0]
-   [-0.1  0.3  0.0]
-   [-0.1  0.3  0.1]
-   [-0.1  0.4  0.6]
-   [-0.1  0.6  0.1]
-   [ 0.1  0.5  0.0]
-   [ 0.2  0.4  0.1]
-   [ 0.0  0.3  0.1]
-   [-0.1  1.0 -0.2]
-   [-0.1  0.6  0.2]
-   [-0.2  0.8 -0.1]
-   [-0.3  0.2  0.1]
-   [ 0.2  0.5  0.1]
-   [-0.5  0.2  0.0]
-   [-0.1  0.3  0.0]
-   [-0.1  0.7 -0.2]
-   [-0.2  0.3  0.0]
-   [-0.3  0.3  0.0]
-   [-0.1  0.7  0.1]
-   [-0.2  0.5  0.1]
-   [-0.2  0.5  0.1]
-   [ 0.2  0.4  0.1]
-   [-0.3  0.4  0.1]
-   [-0.2  0.4  0.5]
-   [-0.5  0.2  0.1]
-   [-0.1  0.8 -0.2]
-   [-0.2  0.6 -0.0]
-   [-0.4  0.2  0.1]
-   [-0.2  0.6  0.2]
-   [ 0.2  0.3  0.0]
-   [-0.0  0.6 -0.0]
-   [-0.1  0.6  0.1]
-   [-0.1  0.7 -0.1]
-   [-0.1  0.3 -0.0]
-   [-0.1  0.3  0.1]
-   [-0.1  0.6  0.1]
-   [-0.2  0.5  0.2]
-   [-0.1  0.3  0.1]
-   [ 0.2  0.4 -0.0]
-   [-0.2  0.6  0.2]
-   [-0.1  0.5  0.2]
-   [-0.1  0.6  0.1]]
+# name: TestOXDNAReading.test_comparing_topologies[top_new_custom].3
+  list([
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+  ])
 # ---
-# name: test_read_oxdna.16
-  [[ 6.8e-02  5.6e-02  4.6e-02]
-   [-3.6e-02 -5.9e-02 -7.2e-02]
-   [-1.6e-02 -6.4e-02 -7.5e-02]
-   [-4.0e-02  9.0e-02 -1.8e-02]
-   [ 6.2e-02  7.8e-02 -1.8e-03]
-   [ 9.7e-02  2.5e-02  1.3e-03]
-   [ 4.1e-02  3.0e-02 -8.6e-02]
-   [ 3.6e-02 -8.4e-02 -4.1e-02]
-   [ 9.8e-02 -1.9e-02 -7.1e-03]
-   [-1.8e-02  7.2e-02  6.7e-02]
-   [ 9.2e-02 -4.8e-03  3.9e-02]
-   [ 7.1e-02 -6.9e-02 -1.6e-02]
-   [-5.8e-03  2.3e-02 -9.7e-02]
-   [ 2.8e-02 -9.1e-02 -2.9e-02]
-   [-2.6e-03  8.7e-02  5.0e-02]
-   [-4.0e-02  9.0e-02 -1.8e-02]
-   [-9.2e-02  1.1e-02 -3.9e-02]
-   [-1.6e-02 -6.4e-02 -7.5e-02]
-   [-1.6e-02  4.5e-02 -8.8e-02]
-   [ 6.2e-02  7.8e-02 -1.8e-03]
-   [-7.8e-02  6.2e-02  1.2e-03]
-   [-1.8e-02  9.8e-02 -6.2e-03]
-   [-3.9e-06 -3.2e-02 -9.5e-02]
-   [ 6.5e-03 -1.5e-02 -9.9e-02]
-   [ 9.3e-02  2.8e-02  2.5e-02]
-   [-2.6e-03  8.7e-02  5.0e-02]
-   [-5.8e-03  2.3e-02 -9.7e-02]
-   [ 4.7e-02 -8.8e-02  2.6e-04]
-   [ 9.2e-02 -4.8e-03  3.9e-02]
-   [ 2.7e-02 -8.4e-02  4.8e-02]
-   [ 1.2e-02 -7.5e-02 -6.5e-02]
-   [-1.8e-02  9.8e-02 -6.2e-03]
-   [ 2.5e-02 -8.0e-02 -5.5e-02]
-   [-4.0e-02  9.0e-02 -1.8e-02]
-   [ 5.7e-02  7.9e-02  2.2e-02]
-   [-8.2e-02 -4.1e-02 -4.0e-02]
-   [ 3.6e-02 -8.4e-02 -4.1e-02]
-   [-1.8e-02  9.8e-02 -6.2e-03]
-   [ 2.0e-02 -7.6e-02  6.1e-02]
-   [-1.9e-02  7.0e-02  6.9e-02]
-   [-1.4e-02  7.5e-02  6.4e-02]
-   [-1.8e-02  2.0e-02 -9.6e-02]
-   [ 3.8e-02  6.0e-02  7.0e-02]
-   [-6.4e-02 -3.7e-02 -6.7e-02]
-   [-9.6e-02  1.0e-02  2.7e-02]
-   [-6.7e-02 -7.4e-02 -4.0e-03]
-   [ 9.2e-03 -2.2e-02 -9.7e-02]
-   [ 8.6e-02 -2.1e-02  4.6e-02]
-   [-7.8e-02  6.2e-02  1.2e-03]
-   [-8.2e-02 -4.1e-02 -4.0e-02]
-   [-2.5e-02  7.0e-02 -6.7e-02]
-   [-8.5e-03  5.9e-03  9.9e-02]
-   [-3.6e-02 -5.9e-02 -7.2e-02]
-   [ 2.8e-02 -9.1e-02 -2.9e-02]
-   [-7.7e-02  6.2e-02  1.3e-02]
-   [-8.2e-03  1.4e-02  9.9e-02]
-   [-9.4e-02  3.3e-02 -5.0e-03]
-   [-8.0e-02  6.0e-02  1.5e-03]
-   [-3.9e-02  5.4e-02  7.5e-02]
-   [-1.8e-02  9.8e-02 -6.2e-03]
-   [-1.8e-02  2.0e-02 -9.6e-02]
-   [-9.5e-02 -3.1e-02 -3.3e-03]
-   [-7.7e-02  3.4e-02  5.5e-02]
-   [ 4.2e-02 -3.8e-02 -8.3e-02]
-   [ 1.0e-02  8.4e-03 -9.9e-02]
-   [-5.8e-03  2.3e-02 -9.7e-02]
-   [-1.8e-02 -6.7e-02  7.2e-02]
-   [-8.2e-02 -4.1e-02 -4.0e-02]
-   [ 7.1e-02 -6.9e-02 -1.6e-02]
-   [-1.3e-02  8.1e-02 -5.7e-02]
-   [ 1.0e-02  8.4e-03 -9.9e-02]
-   [-1.6e-02  4.5e-02 -8.8e-02]
-   [-5.0e-03 -3.3e-02  9.4e-02]
-   [ 4.1e-02  6.7e-02  6.2e-02]
-   [ 6.5e-03 -1.5e-02 -9.9e-02]
-   [ 2.2e-02 -9.7e-02  4.7e-04]
-   [-1.6e-02 -6.4e-02 -7.5e-02]
-   [ 9.3e-02  2.8e-02  2.5e-02]
-   [ 9.6e-02 -6.6e-03 -2.6e-02]
-   [-3.9e-02  5.4e-02  7.5e-02]
-   [ 2.2e-02 -9.7e-02  4.7e-04]
-   [-7.7e-03  9.9e-02  1.4e-02]
-   [-2.5e-02  9.2e-02 -3.0e-02]
-   [ 4.1e-02  3.0e-02 -8.6e-02]
-   [ 3.8e-02  6.0e-02  7.0e-02]
-   [-1.9e-02  2.6e-02 -9.4e-02]
-   [ 7.9e-02 -4.1e-02 -4.6e-02]
-   [-4.5e-02  7.9e-02  4.0e-02]
-   [-9.2e-02  1.1e-02 -3.9e-02]
-   [ 1.8e-02 -5.2e-02 -8.3e-02]
-   [ 7.1e-02 -6.9e-02 -1.6e-02]
-   [-1.8e-02  7.2e-02  6.7e-02]
-   [-2.8e-02  8.0e-02 -5.4e-02]
-   [-9.6e-02  1.0e-02  2.7e-02]
-   [ 6.8e-02  5.6e-02  4.6e-02]
-   [-1.8e-02  9.8e-02 -6.2e-03]
-   [-8.5e-03  5.9e-03  9.9e-02]
-   [ 9.6e-02 -6.6e-03 -2.6e-02]
-   [-9.8e-02 -1.9e-02 -9.5e-03]
-   [ 1.8e-02 -5.2e-02 -8.3e-02]]
+# name: TestOXDNAReading.test_comparing_topologies[top_old]
+  list([
+    list([
+      0,
+      1,
+    ]),
+    list([
+      1,
+      2,
+    ]),
+    list([
+      2,
+      3,
+    ]),
+    list([
+      3,
+      4,
+    ]),
+    list([
+      4,
+      5,
+    ]),
+    list([
+      6,
+      7,
+    ]),
+    list([
+      7,
+      8,
+    ]),
+    list([
+      8,
+      9,
+    ]),
+    list([
+      9,
+      10,
+    ]),
+    list([
+      10,
+      11,
+    ]),
+  ])
 # ---
-# name: test_read_oxdna.17
-  [[-0.0  0.1 -0.1]
-   [-0.1 -0.0  0.1]
-   [ 0.1  0.1 -0.1]
-   [-0.1 -0.0  0.0]
-   [-0.0 -0.0 -0.1]
-   [-0.0  0.0 -0.1]
-   [ 0.0  0.1  0.0]
-   [ 0.1  0.0  0.0]
-   [-0.0 -0.0  0.1]
-   [ 0.1  0.0 -0.0]
-   [ 0.0  0.0 -0.1]
-   [-0.1 -0.1  0.0]
-   [-0.1 -0.0  0.0]
-   [-0.1 -0.0 -0.0]
-   [ 0.0  0.0 -0.1]
-   [-0.1 -0.0  0.0]
-   [ 0.0  0.1 -0.1]
-   [ 0.1  0.1 -0.1]
-   [ 0.1  0.0 -0.0]
-   [-0.0 -0.0 -0.1]
-   [ 0.0  0.0 -0.1]
-   [ 0.1  0.0 -0.0]
-   [-0.1 -0.0  0.0]
-   [ 0.1  0.0  0.0]
-   [-0.0  0.1 -0.1]
-   [ 0.0  0.0 -0.1]
-   [-0.1 -0.0  0.0]
-   [ 0.1  0.0  0.1]
-   [ 0.0  0.0 -0.1]
-   [-0.1 -0.0 -0.0]
-   [-0.1 -0.0 -0.0]
-   [ 0.1  0.0 -0.0]
-   [-0.1 -0.1  0.0]
-   [-0.1 -0.0  0.0]
-   [ 0.0 -0.0  0.1]
-   [-0.0 -0.0  0.1]
-   [ 0.1  0.0  0.0]
-   [ 0.1  0.0 -0.0]
-   [ 0.1  0.0  0.0]
-   [ 0.1  0.0 -0.0]
-   [-0.0 -0.1  0.1]
-   [ 0.1  0.0 -0.0]
-   [-0.0 -0.1  0.1]
-   [ 0.1  0.0 -0.1]
-   [ 0.0 -0.1  0.1]
-   [-0.0  0.0  0.1]
-   [-0.1 -0.0 -0.0]
-   [-0.0 -0.1  0.1]
-   [ 0.0  0.0 -0.1]
-   [-0.0 -0.0  0.1]
-   [-0.1 -0.0  0.0]
-   [-0.1 -0.0 -0.0]
-   [-0.1 -0.0  0.1]
-   [-0.1 -0.0 -0.0]
-   [ 0.0 -0.0  0.1]
-   [-0.1 -0.1  0.0]
-   [ 0.0  0.0  0.1]
-   [ 0.0  0.0 -0.1]
-   [-0.1 -0.1  0.0]
-   [ 0.1  0.0 -0.0]
-   [ 0.1  0.0 -0.0]
-   [-0.0  0.0  0.1]
-   [ 0.0 -0.1  0.1]
-   [ 0.1  0.0  0.0]
-   [ 0.1  0.0  0.0]
-   [-0.1 -0.0  0.0]
-   [ 0.1  0.1  0.1]
-   [-0.0 -0.0  0.1]
-   [-0.1 -0.1  0.0]
-   [-0.1  0.0  0.0]
-   [ 0.1  0.0  0.0]
-   [ 0.1  0.0 -0.0]
-   [-0.1 -0.1 -0.0]
-   [ 0.0  0.1 -0.1]
-   [ 0.1  0.0  0.0]
-   [ 0.1  0.0  0.0]
-   [ 0.1  0.1 -0.1]
-   [-0.0  0.1 -0.1]
-   [-0.0  0.1 -0.1]
-   [-0.1 -0.1  0.0]
-   [ 0.1  0.0  0.0]
-   [ 0.0 -0.0  0.1]
-   [ 0.1  0.0 -0.0]
-   [ 0.0  0.1  0.0]
-   [-0.0 -0.1  0.1]
-   [-0.1  0.0  0.0]
-   [ 0.0  0.1 -0.1]
-   [-0.1 -0.1  0.0]
-   [ 0.0  0.1 -0.1]
-   [ 0.0  0.1 -0.0]
-   [-0.1 -0.1  0.0]
-   [ 0.1  0.0 -0.0]
-   [ 0.1  0.0 -0.0]
-   [ 0.0 -0.1  0.1]
-   [-0.0  0.1 -0.1]
-   [ 0.1  0.0 -0.0]
-   [-0.1 -0.0 -0.0]
-   [-0.0  0.1 -0.1]
-   [ 0.0 -0.1  0.1]
-   [ 0.0  0.1 -0.0]]
+# name: TestOXDNAReading.test_comparing_topologies[top_old].1
+  list([
+    1,
+    1,
+    1,
+    1,
+    1,
+    1,
+    1,
+    1,
+    1,
+    1,
+    1,
+    1,
+  ])
 # ---
-# name: test_read_oxdna.18
-  [[-1.0e-02  6.0e-02  4.2e-03]
-   [ 2.0e-03  1.5e-02  6.5e-02]
-   [ 2.2e-02  1.9e-02  6.3e-03]
-   [ 5.5e-02 -3.0e-02 -2.1e-02]
-   [-1.0e-02  2.1e-02  1.1e-02]
-   [ 2.1e-02  3.4e-02  8.3e-03]
-   [-2.0e-02  1.3e-02  3.4e-02]
-   [ 8.2e-03  4.7e-03 -4.0e-02]
-   [ 1.9e-04  2.8e-02  3.6e-02]
-   [-1.5e-02  2.1e-02  2.7e-02]
-   [-1.6e-02 -5.1e-03  1.2e-02]
-   [ 2.4e-02 -2.8e-02  3.3e-04]
-   [-1.3e-02  8.6e-03  2.8e-02]
-   [-5.4e-04  4.0e-02 -1.4e-02]
-   [ 8.4e-03 -1.5e-02 -2.7e-02]
-   [ 5.5e-02 -3.0e-02 -2.1e-02]
-   [ 1.0e-02  1.1e-02 -1.5e-02]
-   [ 2.2e-02  1.9e-02  6.3e-03]
-   [ 1.4e-02  3.0e-02 -3.1e-02]
-   [-1.0e-02  2.1e-02  1.1e-02]
-   [-1.5e-02  3.7e-02  1.0e-02]
-   [ 1.4e-02  4.2e-02  2.6e-02]
-   [ 2.2e-02  1.5e-02  1.4e-02]
-   [-4.7e-03 -9.1e-03 -3.0e-02]
-   [ 2.9e-02  9.3e-04  1.7e-02]
-   [ 8.4e-03 -1.5e-02 -2.7e-02]
-   [-1.3e-02  8.6e-03  2.8e-02]
-   [ 3.8e-02  2.9e-02 -1.4e-02]
-   [-1.6e-02 -5.1e-03  1.2e-02]
-   [-1.8e-03 -3.2e-02  3.8e-03]
-   [ 2.9e-02  5.6e-03  1.3e-03]
-   [ 1.4e-02  4.2e-02  2.6e-02]
-   [-3.2e-02  3.3e-02 -2.0e-02]
-   [ 5.5e-02 -3.0e-02 -2.1e-02]
-   [ 3.0e-03  2.6e-02  2.3e-02]
-   [-1.2e-02  3.3e-03  1.9e-03]
-   [ 8.2e-03  4.7e-03 -4.0e-02]
-   [ 1.4e-02  4.2e-02  2.6e-02]
-   [-2.4e-02 -2.9e-02 -1.2e-02]
-   [-1.7e-02  4.3e-03 -7.8e-02]
-   [ 3.8e-02  2.7e-02  1.1e-01]
-   [-4.8e-02  6.6e-02 -1.7e-02]
-   [-2.8e-02 -6.7e-02  1.9e-03]
-   [-4.9e-03  1.8e-02  4.4e-05]
-   [ 1.3e-02 -1.7e-02 -1.8e-02]
-   [ 9.5e-03  1.7e-02  1.3e-02]
-   [ 9.9e-03  2.4e-02  1.7e-02]
-   [-7.7e-03  4.0e-02  5.0e-04]
-   [-1.5e-02  3.7e-02  1.0e-02]
-   [-1.2e-02  3.3e-03  1.9e-03]
-   [-3.1e-02 -7.3e-03 -2.0e-02]
-   [-5.6e-02  4.8e-02  4.7e-02]
-   [ 2.0e-03  1.5e-02  6.5e-02]
-   [-5.4e-04  4.0e-02 -1.4e-02]
-   [-1.9e-03 -9.6e-04 -1.0e-02]
-   [ 3.2e-04  1.1e-02 -3.1e-02]
-   [-3.6e-02 -3.1e-03  5.8e-03]
-   [-2.5e-04 -2.2e-02  3.5e-02]
-   [ 4.6e-03 -1.7e-02  1.3e-02]
-   [ 1.4e-02  4.2e-02  2.6e-02]
-   [-4.8e-02  6.6e-02 -1.7e-02]
-   [ 1.8e-02 -8.6e-03 -5.4e-02]
-   [ 3.1e-02  2.5e-02  1.7e-02]
-   [-4.4e-02 -3.5e-02 -5.4e-02]
-   [ 6.2e-02  4.2e-03  2.4e-02]
-   [-1.3e-02  8.6e-03  2.8e-02]
-   [ 1.6e-02 -7.0e-03  2.8e-02]
-   [-1.2e-02  3.3e-03  1.9e-03]
-   [ 2.4e-02 -2.8e-02  3.3e-04]
-   [-3.3e-03 -5.2e-02  6.3e-03]
-   [ 6.2e-02  4.2e-03  2.4e-02]
-   [ 1.4e-02  3.0e-02 -3.1e-02]
-   [ 1.7e-02  3.8e-02 -1.2e-03]
-   [ 1.4e-02  3.6e-02 -1.2e-02]
-   [-4.7e-03 -9.1e-03 -3.0e-02]
-   [ 4.1e-03 -1.6e-02 -4.5e-02]
-   [ 2.2e-02  1.9e-02  6.3e-03]
-   [ 2.9e-02  9.3e-04  1.7e-02]
-   [ 7.9e-04  2.7e-02  2.7e-02]
-   [ 4.6e-03 -1.7e-02  1.3e-02]
-   [ 4.1e-03 -1.6e-02 -4.5e-02]
-   [ 2.0e-02 -5.2e-02  1.8e-02]
-   [ 5.0e-02 -2.7e-02 -2.0e-02]
-   [-2.0e-02  1.3e-02  3.4e-02]
-   [-2.8e-02 -6.7e-02  1.9e-03]
-   [-2.3e-02 -3.0e-02  5.5e-03]
-   [ 1.9e-02  5.0e-02 -3.5e-02]
-   [ 2.7e-03 -1.4e-02 -1.1e-03]
-   [ 1.0e-02  1.1e-02 -1.5e-02]
-   [ 7.1e-03  6.9e-02 -4.1e-02]
-   [ 2.4e-02 -2.8e-02  3.3e-04]
-   [-1.5e-02  2.1e-02  2.7e-02]
-   [-1.4e-03  1.2e-02 -4.1e-02]
-   [ 1.3e-02 -1.7e-02 -1.8e-02]
-   [-1.0e-02  6.0e-02  4.2e-03]
-   [ 1.4e-02  4.2e-02  2.6e-02]
-   [-5.6e-02  4.8e-02  4.7e-02]
-   [ 7.9e-04  2.7e-02  2.7e-02]
-   [ 1.9e-03  9.0e-03  3.5e-02]
-   [ 7.1e-03  6.9e-02 -4.1e-02]]
+# name: TestOXDNAReading.test_comparing_topologies[top_old].2
+  list([
+    1.0,
+    1.0,
+    1.0,
+    1.0,
+    1.0,
+    1.0,
+    2.0,
+    2.0,
+    2.0,
+    2.0,
+    2.0,
+    2.0,
+  ])
 # ---
-# name: test_read_oxdna.19
-  [[ 0.1 -0.1 -0.1]
-   [ 0.2  0.0  0.1]
-   [ 0.5 -0.0 -0.2]
-   [ 0.0 -0.6  0.4]
-   [ 0.0  0.3  0.2]
-   [-0.7 -0.0  0.0]
-   [-0.3  0.0  0.5]
-   [ 0.3  0.1  0.6]
-   [ 0.2  0.5  0.4]
-   [ 0.1 -0.2  0.6]
-   [-0.3  0.5  0.1]
-   [ 0.3  0.1 -0.1]
-   [ 0.0  0.0  0.2]
-   [-0.0 -0.3 -0.1]
-   [-0.6  0.1 -0.6]
-   [ 0.0 -0.6  0.4]
-   [ 0.1  0.5 -0.0]
-   [ 0.5 -0.0 -0.2]
-   [ 0.5  0.1  0.1]
-   [ 0.0  0.3  0.2]
-   [ 0.1 -0.3  0.0]
-   [-0.1  0.1  0.4]
-   [ 0.2 -0.1  0.4]
-   [ 0.7 -0.1  0.5]
-   [-0.3 -0.0 -0.3]
-   [-0.6  0.1 -0.6]
-   [ 0.0  0.0  0.2]
-   [-0.2 -0.1 -0.2]
-   [-0.3  0.5  0.1]
-   [ 0.1  0.1  0.2]
-   [ 0.3  0.3  0.5]
-   [-0.1  0.1  0.4]
-   [-0.1 -0.1  0.3]
-   [ 0.0 -0.6  0.4]
-   [-0.0 -0.2  0.1]
-   [-0.2 -0.1  0.0]
-   [ 0.3  0.1  0.6]
-   [-0.1  0.1  0.4]
-   [-0.3  0.7  0.1]
-   [-0.2 -0.1 -0.5]
-   [-0.0 -0.5  0.5]
-   [-0.5  0.0  0.1]
-   [ 0.7 -0.4  0.4]
-   [-0.6  0.1 -0.1]
-   [ 0.0  0.3 -0.6]
-   [ 0.0  0.3  0.0]
-   [ 0.1  0.2  0.7]
-   [ 0.1 -0.1 -0.2]
-   [ 0.1 -0.3  0.0]
-   [-0.2 -0.1  0.0]
-   [-0.3 -0.4  0.2]
-   [-0.3 -0.1 -0.1]
-   [ 0.2  0.0  0.1]
-   [-0.0 -0.3 -0.1]
-   [-0.1  0.0  0.2]
-   [ 0.1  0.4 -0.4]
-   [-0.3 -0.3 -0.2]
-   [ 0.2  0.2  0.3]
-   [ 0.0  0.5 -0.1]
-   [-0.1  0.1  0.4]
-   [-0.5  0.0  0.1]
-   [ 0.3  0.2  0.2]
-   [ 0.1 -0.2  0.0]
-   [ 0.0 -0.0  0.7]
-   [ 0.1  0.8 -0.3]
-   [ 0.0  0.0  0.2]
-   [-0.3 -0.4 -0.3]
-   [-0.2 -0.1  0.0]
-   [ 0.3  0.1 -0.1]
-   [ 0.3 -0.0 -0.3]
-   [ 0.1  0.8 -0.3]
-   [ 0.5  0.1  0.1]
-   [ 0.0  0.2  0.4]
-   [ 0.2 -0.3  0.5]
-   [ 0.7 -0.1  0.5]
-   [ 0.1 -0.5  0.2]
-   [ 0.5 -0.0 -0.2]
-   [-0.3 -0.0 -0.3]
-   [-0.3  0.6  0.5]
-   [ 0.0  0.5 -0.1]
-   [ 0.1 -0.5  0.2]
-   [ 0.4  0.3 -0.4]
-   [ 0.2 -0.2  0.0]
-   [-0.3  0.0  0.5]
-   [ 0.7 -0.4  0.4]
-   [-0.2 -0.4  0.1]
-   [-0.1 -0.5 -0.0]
-   [ 0.3 -0.4  0.2]
-   [ 0.1  0.5 -0.0]
-   [ 0.3 -0.2  0.0]
-   [ 0.3  0.1 -0.1]
-   [ 0.1 -0.2  0.6]
-   [-0.1  0.5  0.4]
-   [ 0.0  0.3 -0.6]
-   [ 0.1 -0.1 -0.1]
-   [-0.1  0.1  0.4]
-   [-0.3 -0.1 -0.1]
-   [-0.3  0.6  0.5]
-   [-0.1  0.4  0.3]
-   [ 0.3 -0.2  0.0]]
+# name: TestOXDNAReading.test_comparing_topologies[top_old].3
+  list([
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+    42,
+  ])
 # ---
-# name: test_read_oxdna.2
-  [[0.4 0.5 0.8 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.5 0.8 0.0]
-   [0.8 0.4 0.4 0.0]
-   [0.4 0.8 0.5 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.7 0.8 0.4 0.0]
-   [0.4 0.8 0.5 0.0]]
+# name: TestOXDNAReading.test_univ_snapshot
+  [[-2.7e-03  3.5e-03  6.1e-03]
+   [-2.8e-03  3.7e-03  5.7e-03]
+   [-2.8e-03  4.0e-03  5.3e-03]
+   [-2.7e-03  4.3e-03  5.0e-03]
+   [-2.3e-03  4.6e-03  4.6e-03]
+   [-1.9e-03  4.6e-03  4.3e-03]
+   [-1.5e-03  4.5e-03  4.0e-03]
+   [-1.4e-03  4.4e-03  3.4e-03]
+   [-1.4e-03  4.2e-03  3.0e-03]
+   [-1.6e-03  4.1e-03  2.5e-03]
+   [-1.9e-03  4.2e-03  2.0e-03]
+   [-1.6e-03  3.0e-03  9.0e-04]
+   [-1.2e-03  2.8e-03  7.2e-04]
+   [-7.7e-04  2.8e-03  4.1e-04]
+   [-4.2e-04  3.0e-03  8.1e-05]
+   [-1.3e-04  3.4e-03 -1.3e-04]
+   [ 1.4e-04  3.8e-03 -1.6e-04]
+   [ 5.4e-04  4.2e-03 -1.9e-05]
+   [ 7.2e-04  4.4e-03  3.7e-04]
+   [ 1.1e-03  4.6e-03  7.6e-04]
+   [ 1.4e-03  4.5e-03  1.1e-03]
+   [ 1.9e-03  4.5e-03  1.2e-03]
+   [ 2.1e-03  4.4e-03  5.7e-05]
+   [ 1.8e-03  4.0e-03  1.1e-04]
+   [ 1.6e-03  3.7e-03  3.2e-04]
+   [ 1.2e-03  3.4e-03  5.9e-04]
+   [ 7.4e-04  3.4e-03  8.6e-04]
+   [ 2.4e-04  3.5e-03  1.0e-03]
+   [-1.8e-04  3.7e-03  1.0e-03]
+   [-6.2e-04  3.9e-03  8.5e-04]
+   [-9.7e-04  4.0e-03  3.9e-04]
+   [-1.5e-03  3.8e-03  8.9e-05]
+   [-1.7e-03  3.4e-03 -1.7e-04]
+   [-2.1e-03  3.0e-03 -2.2e-04]
+   [-2.3e-03  2.5e-03 -5.8e-06]
+   [-2.7e-03  2.3e-03  3.2e-04]
+   [-3.2e-03  2.3e-03  6.7e-04]
+   [-3.5e-03  2.5e-03  1.0e-03]
+   [-4.0e-03  2.8e-03  1.0e-03]
+   [-4.6e-03  2.9e-03  9.7e-04]
+   [-5.1e-03  2.9e-03  6.9e-04]
+   [-5.4e-03  2.8e-03  3.4e-04]
+   [-5.8e-03  2.5e-03  5.3e-05]
+   [-6.0e-03  2.0e-03 -1.2e-04]
+   [-6.0e-03  2.0e-03  1.1e-03]
+   [-5.5e-03  1.8e-03  9.9e-04]
+   [-5.1e-03  1.7e-03  7.3e-04]
+   [-4.7e-03  1.8e-03  4.0e-04]
+   [-4.3e-03  2.1e-03  1.1e-04]
+   [-4.1e-03  2.5e-03 -1.5e-04]
+   [-3.7e-03  2.9e-03 -2.3e-04]
+   [-3.3e-03  3.3e-03 -3.4e-05]
+   [-3.0e-03  3.5e-03  3.7e-04]
+   [-2.6e-03  3.4e-03  7.2e-04]
+   [-2.1e-03  3.2e-03  9.3e-04]
+   [-2.1e-03  4.6e-03  1.6e-03]
+   [-2.2e-03  5.1e-03  1.4e-03]
+   [-2.3e-03  5.5e-03  1.4e-03]
+   [-2.1e-03  6.1e-03  1.3e-03]
+   [-1.7e-03  6.5e-03  1.2e-03]
+   [-1.4e-03  6.7e-03  8.6e-04]
+   [-9.9e-04  6.7e-03  5.3e-04]
+   [-6.8e-04  6.8e-03  8.2e-05]
+   [-6.4e-04  6.8e-03 -4.7e-04]
+   [-7.8e-04  6.9e-03 -9.7e-04]
+   [-9.4e-04  7.1e-03 -1.4e-03]
+   [-1.0e-03  7.6e-03 -1.6e-03]
+   [-8.0e-04  8.0e-03 -1.8e-03]
+   [-1.6e-03  8.9e-03 -1.9e-03]
+   [-1.4e-03  8.2e-03 -2.6e-03]
+   [-1.8e-03  8.4e-03 -3.2e-03]
+   [-1.4e-03  8.4e-03 -3.1e-03]
+   [-9.0e-04  8.3e-03 -2.9e-03]
+   [-6.0e-04  8.7e-03 -2.7e-03]
+   [-6.2e-04  9.1e-03 -2.5e-03]
+   [-5.5e-04  9.3e-03 -2.0e-03]
+   [-6.2e-04  7.9e-03 -6.4e-04]
+   [-1.0e-03  7.9e-03 -4.1e-04]
+   [-1.5e-03  7.5e-03 -3.7e-04]
+   [-1.8e-03  7.0e-03 -3.9e-04]
+   [-1.8e-03  6.5e-03 -1.8e-04]
+   [-1.7e-03  6.0e-03 -3.9e-05]
+   [-1.5e-03  5.7e-03  2.3e-04]
+   [-1.2e-03  5.6e-03  6.1e-04]
+   [-1.1e-03  5.4e-03  1.1e-03]
+   [-1.1e-03  5.3e-03  1.6e-03]
+   [-1.2e-03  5.2e-03  2.1e-03]
+   [-1.5e-03  5.2e-03  2.5e-03]
+   [-2.0e-03  5.2e-03  2.8e-03]
+   [-2.3e-03  4.9e-03  3.0e-03]
+   [-2.6e-03  4.5e-03  3.4e-03]
+   [-2.6e-03  4.0e-03  3.7e-03]
+   [-2.4e-03  3.6e-03  4.1e-03]
+   [-2.1e-03  3.5e-03  4.4e-03]
+   [-1.8e-03  3.5e-03  4.8e-03]
+   [-1.7e-03  3.7e-03  5.3e-03]
+   [-1.7e-03  4.1e-03  5.7e-03]
+   [-1.9e-03  4.4e-03  6.1e-03]]
 # ---
-# name: test_read_oxdna.20
-  [ True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True]
+# name: TestOXDNAReading.test_univ_snapshot.1
+  ['C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C'
+   'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C'
+   'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C'
+   'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C'
+   'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C'
+   'C' 'C' 'C' 'C' 'C' 'C' 'C' 'C']
 # ---
-# name: test_read_oxdna.21
-  [[1985 1986]
-   [1386 1387]
-   [2062 2066]
-   [ 189  195]
-   [1142 1146]
-   [1902 1903]
-   [ 507  508]
-   [  24   25]
-   [   6   12]
-   [ 374  380]
-   [1630 1631]
-   [1422 1423]
-   [1102 1106]
-   [1895 1892]
-   [1825 1826]
-   [ 836  840]
-   [ 692  693]
-   [1922 1923]
-   [  34   40]
-   [ 552  553]
-   [1154 1155]
-   [2008 2009]
-   [ 373  374]
-   [1813 1814]
-   [ 951  948]
-   [1288 1289]
-   [1292 1293]
-   [1681 1682]
-   [ 133  134]
-   [ 352  353]
-   [1359 1356]
-   [1331 1328]
-   [1729 1730]
-   [2017 2018]
-   [1809 1810]
-   [ 523  524]
-   [1631 1628]
-   [2014 2015]
-   [1486 1487]
-   [1692 1693]
-   [ 244  250]
-   [2126 2127]
-   [ 979  976]
-   [ 734  738]
-   [ 245  251]
-   [ 807  811]
-   [2005 2006]
-   [ 939  936]
-   [2016 2017]
-   [ 461  456]
-   [1035 1032]
-   [ 132  133]
-   [1882 1883]
-   [ 369  370]
-   [1734 1735]
-   [1552 1553]
-   [1994 1995]
-   [ 612  616]
-   [ 147  148]
-   [  61   62]
-   [1426 1427]
-   [ 384  385]
-   [2079 2083]
-   [1608 1609]
-   [ 804  805]
-   [1149 1150]
-   [2094 2095]
-   [ 355  356]
-   [1224 1225]
-   [1390 1394]
-   [1580 1581]
-   [1726 1727]
-   [2019 2016]
-   [1195 1192]
-   [  71   77]
-   [1550 1551]
-   [ 804  808]
-   [ 485  491]
-   [1460 1464]
-   [ 992  993]
-   [ 650  651]
-   [ 795  792]
-   [1429 1430]
-   [ 237  238]
-   [ 161  167]
-   [1184 1185]
-   [1671 1675]
-   [1255 1252]
-   [ 377  372]
-   [ 226  227]
-   [1479 1483]
-   [ 533  528]
-   [ 671  675]
-   [1781 1785]
-   [ 365  360]
-   [ 855  859]
-   [1141 1142]
-   [ 564  570]
-   [ 373  379]
-   [1450 1451]]
+# name: TestOXDNAReading.test_univ_snapshot.2
+  [1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
+   1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
+   1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1]
 # ---
-# name: test_read_oxdna.22
-  [ True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True]
-# ---
-# name: test_read_oxdna.23
-  [ True  True  True False  True  True False False False False  True  True
-    True  True  True  True  True  True False False  True  True False  True
-    True  True  True  True False False  True  True  True  True  True False
-    True  True  True False  True  True  True False  True  True  True False
-    True  True False  True  True  True  True False False  True False  True
-    True  True  True  True False  True  True  True  True  True  True False
-    True  True False  True  True  True  True  True False False  True  True
-    True False False  True False  True  True False  True  True False False
-    True False  True  True]
-# ---
-# name: test_read_oxdna.3
-  [[-0.2  0.5  0.6]
-   [-0.1  0.3  0.0]
-   [-0.1  0.6  0.0]
-   [-0.6  0.2  0.1]
-   [-0.1  0.4  0.4]
-   [-0.3  0.3  0.6]
-   [ 0.2  0.3  0.1]
-   [-0.2  0.6 -0.1]
-   [-0.0  0.6 -0.1]
-   [-0.2  0.3  0.1]
-   [-0.3  0.5  0.5]
-   [-0.5  0.1  0.1]
-   [-0.1  0.6  0.1]
-   [-0.2  0.3 -0.1]
-   [-0.1  0.8 -0.3]
-   [-0.3  0.3  0.3]
-   [-0.2  0.3  0.4]
-   [ 0.0  0.4 -0.0]
-   [-0.2  0.3 -0.1]
-   [-0.1  0.4  0.5]
-   [-0.6  0.1  0.1]
-   [-0.0  0.4 -0.1]
-   [-0.1  0.8 -0.3]
-   [-0.3  0.6  0.2]
-   [-0.0  0.4 -0.0]
-   [-0.0  0.6  0.1]
-   [-0.1  0.8 -0.2]
-   [-0.6  0.2 -0.0]
-   [-0.1  1.0 -0.2]
-   [-0.1  0.4  0.5]
-   [-0.2  0.3 -0.0]
-   [-0.4  0.3 -0.0]
-   [-0.0  0.4 -0.0]
-   [-0.1  0.4  0.3]
-   [-0.2  0.2  0.0]
-   [-0.0  0.7  0.1]
-   [-0.1  0.6  0.1]
-   [-0.2  0.3 -0.1]
-   [-0.2  0.6  0.2]
-   [-0.1  0.6  0.2]
-   [-0.2  0.5  0.5]
-   [-0.2  0.3  0.5]
-   [-0.5  0.3 -0.0]
-   [-0.1  0.9 -0.3]
-   [-0.3  0.4 -0.0]
-   [-0.1  0.7  0.1]
-   [ 0.1  0.5  0.2]
-   [-0.0  0.4 -0.1]
-   [-0.1  0.6  0.2]
-   [-0.3  0.5  0.3]
-   [-0.2  0.3 -0.1]
-   [ 0.1  0.5  0.1]
-   [-0.5  0.1  0.1]
-   [-0.3  0.3  0.1]
-   [-0.2  0.3 -0.0]
-   [-0.1  0.6 -0.1]
-   [-0.1  0.6 -0.0]
-   [-0.4  0.3  0.1]
-   [ 0.2  0.4  0.0]
-   [-0.3  0.2  0.1]
-   [-0.3  0.4  0.5]
-   [-0.1  0.3 -0.1]
-   [-0.0  0.4  0.1]
-   [-0.3  0.5  0.6]
-   [-0.2  0.5  0.2]
-   [-0.3  0.4  0.1]
-   [-0.1  0.6 -0.1]
-   [-0.1  0.7 -0.1]
-   [-0.1  0.8 -0.2]
-   [-0.4  0.3 -0.0]
-   [ 0.2  0.4  0.2]
-   [-0.1  0.4  0.5]
-   [-0.2  0.4  0.2]
-   [-0.2  0.4 -0.0]
-   [-0.1  0.8 -0.3]
-   [-0.1  0.8 -0.2]
-   [-0.0  0.4 -0.0]
-   [-0.1  0.6  0.1]
-   [-0.3  0.3  0.1]
-   [ 0.1  0.4  0.1]
-   [-0.2  0.9 -0.2]
-   [-0.1  0.6  0.1]
-   [-0.1  0.4  0.3]
-   [-0.1  0.9 -0.0]
-   [-0.4  0.4  0.0]
-   [-0.1  0.3  0.5]
-   [-0.1  1.0 -0.3]
-   [-0.2  0.3  0.4]
-   [-0.2  0.5  0.3]
-   [-0.1  0.6  0.1]
-   [-0.2  0.8 -0.2]
-   [-0.2  0.8 -0.4]
-   [-0.1  0.3 -0.0]
-   [-0.3  0.5  0.3]
-   [-0.1  0.4  0.4]
-   [-0.6  0.1  0.1]
-   [-0.3  0.2  0.1]
-   [-0.5  0.3  0.1]
-   [ 0.1  0.3  0.1]
-   [-0.1  0.7  0.1]]
-# ---
-# name: test_read_oxdna.4
-  [[-6.7e-02 -7.4e-02 -4.0e-03]
-   [-1.8e-02  9.8e-02 -6.2e-03]
-   [-1.4e-02  7.5e-02  6.4e-02]
-   [-1.3e-04  2.0e-03 -1.0e-01]
-   [-9.0e-02 -3.5e-02 -2.7e-02]
-   [ 6.2e-02  7.8e-02 -1.8e-03]
-   [-4.5e-02  7.9e-02  4.0e-02]
-   [ 7.7e-02  2.4e-02  6.0e-02]
-   [-7.8e-02  6.2e-02  1.2e-03]
-   [ 6.5e-03 -1.5e-02 -9.9e-02]
-   [ 6.2e-02 -7.7e-02 -1.2e-02]
-   [-2.5e-02  9.2e-02 -3.0e-02]
-   [-7.7e-02  3.4e-02  5.5e-02]
-   [-8.2e-03  1.4e-02  9.9e-02]
-   [ 5.9e-03  1.0e-01  6.9e-04]
-   [ 9.1e-02  3.5e-02  2.1e-02]
-   [ 5.7e-02  7.9e-02  2.2e-02]
-   [ 1.2e-02 -2.3e-02  9.7e-02]
-   [-5.0e-03 -3.3e-02  9.4e-02]
-   [-7.7e-02  6.2e-02  1.3e-02]
-   [-1.6e-02  4.5e-02 -8.8e-02]
-   [-4.2e-03  3.5e-02  9.4e-02]
-   [-5.3e-02  7.7e-02  3.6e-02]
-   [ 9.6e-02 -6.6e-03 -2.6e-02]
-   [-4.2e-03  3.5e-02  9.4e-02]
-   [-6.4e-02 -3.7e-02 -6.7e-02]
-   [ 4.1e-02  3.0e-02 -8.6e-02]
-   [ 2.9e-02 -6.1e-02  7.3e-02]
-   [ 4.7e-02 -8.8e-02  2.6e-04]
-   [-9.4e-02  3.3e-02 -5.0e-03]
-   [-8.2e-03  1.4e-02  9.9e-02]
-   [ 1.5e-02  9.5e-03  9.8e-02]
-   [ 1.2e-02 -2.3e-02  9.7e-02]
-   [-9.8e-02  1.6e-02 -1.2e-02]
-   [-2.3e-02  7.4e-02  6.4e-02]
-   [-6.4e-02 -3.7e-02 -6.7e-02]
-   [-7.7e-02  3.4e-02  5.5e-02]
-   [-8.2e-03  1.4e-02  9.9e-02]
-   [-3.0e-02 -8.4e-02 -4.5e-02]
-   [-9.8e-02 -1.9e-02 -9.5e-03]
-   [ 2.6e-02 -9.6e-02 -4.9e-03]
-   [-7.7e-03  9.9e-02  1.4e-02]
-   [ 2.4e-02 -9.2e-02  3.2e-02]
-   [-6.7e-02  2.3e-03  7.4e-02]
-   [ 2.0e-02 -7.6e-02  6.1e-02]
-   [-1.6e-02 -6.4e-02 -7.5e-02]
-   [ 4.2e-02 -3.8e-02 -8.3e-02]
-   [-4.2e-03  3.5e-02  9.4e-02]
-   [-9.8e-02 -1.9e-02 -9.5e-03]
-   [ 7.9e-02 -6.1e-02 -8.3e-03]
-   [-8.2e-03  1.4e-02  9.9e-02]
-   [ 3.6e-02 -8.4e-02 -4.1e-02]
-   [-1.6e-02  4.5e-02 -8.8e-02]
-   [ 2.9e-02 -6.0e-02 -7.4e-02]
-   [-8.2e-03  1.4e-02  9.9e-02]
-   [-2.6e-03  8.7e-02  5.0e-02]
-   [-1.4e-02  7.5e-02  6.4e-02]
-   [-3.9e-06 -3.2e-02 -9.5e-02]
-   [-3.9e-02  5.4e-02  7.5e-02]
-   [-1.8e-02  9.8e-02  7.5e-04]
-   [ 9.3e-02 -3.5e-02 -9.2e-03]
-   [-5.0e-03 -3.3e-02  9.4e-02]
-   [ 9.2e-03 -2.2e-02 -9.7e-02]
-   [ 9.3e-02 -3.5e-02 -9.2e-03]
-   [ 9.3e-02  2.8e-02  2.5e-02]
-   [ 2.2e-02 -9.7e-02  4.7e-04]
-   [-7.8e-02  6.2e-02  1.2e-03]
-   [-2.6e-03  8.7e-02  5.0e-02]
-   [ 9.2e-02 -4.8e-03  3.9e-02]
-   [ 1.5e-02  9.5e-03  9.8e-02]
-   [ 1.0e-02  8.4e-03 -9.9e-02]
-   [-9.4e-02  3.3e-02 -5.0e-03]
-   [-1.9e-02  9.5e-02  2.5e-02]
-   [ 2.7e-02 -8.4e-02  4.8e-02]
-   [-5.3e-02  7.7e-02  3.6e-02]
-   [ 6.3e-02 -7.8e-02 -2.8e-03]
-   [ 1.2e-02 -2.3e-02  9.7e-02]
-   [-7.7e-02  3.4e-02  5.5e-02]
-   [-1.9e-02  2.6e-02 -9.4e-02]
-   [ 4.2e-02 -3.8e-02 -8.3e-02]
-   [ 5.3e-02  8.1e-02  2.4e-02]
-   [-7.7e-02  3.4e-02  5.5e-02]
-   [-9.8e-02  1.6e-02 -1.2e-02]
-   [-3.6e-02 -5.9e-02 -7.2e-02]
-   [ 2.0e-02 -7.6e-02  6.1e-02]
-   [-7.7e-02  6.2e-02  1.3e-02]
-   [-1.8e-02 -6.7e-02  7.2e-02]
-   [-7.7e-03  9.9e-02  1.4e-02]
-   [ 3.0e-02 -9.0e-02 -3.1e-02]
-   [-7.7e-02  3.4e-02  5.5e-02]
-   [ 9.2e-02 -4.8e-03  3.9e-02]
-   [ 5.9e-03  1.0e-01  6.9e-04]
-   [-5.0e-03 -3.3e-02  9.4e-02]
-   [ 7.9e-02 -6.1e-02 -8.3e-03]
-   [-9.0e-02 -3.5e-02 -2.7e-02]
-   [-1.3e-04  2.0e-03 -1.0e-01]
-   [-1.3e-02  8.1e-02 -5.7e-02]
-   [ 2.8e-02 -9.1e-02 -2.9e-02]
-   [-4.0e-02  9.0e-02 -1.8e-02]
-   [-1.6e-02 -6.4e-02 -7.5e-02]]
-# ---
-# name: test_read_oxdna.5
-  [[-0.0  0.0  0.1]
-   [ 0.1  0.0 -0.0]
-   [-0.0 -0.1  0.1]
-   [ 0.1  0.0  0.0]
-   [ 0.0  0.0 -0.1]
-   [-0.0 -0.0 -0.1]
-   [-0.1 -0.1  0.0]
-   [-0.0 -0.1  0.1]
-   [ 0.0  0.0 -0.1]
-   [ 0.1  0.0  0.0]
-   [ 0.0  0.0 -0.1]
-   [ 0.1  0.0 -0.0]
-   [ 0.0 -0.1  0.1]
-   [-0.1 -0.1  0.0]
-   [ 0.1 -0.0  0.1]
-   [-0.0 -0.0  0.1]
-   [ 0.0 -0.0  0.1]
-   [ 0.1  0.0 -0.0]
-   [-0.1 -0.1 -0.0]
-   [ 0.0 -0.0  0.1]
-   [ 0.1  0.0 -0.0]
-   [ 0.1  0.0 -0.0]
-   [ 0.1  0.0  0.1]
-   [-0.0  0.1 -0.1]
-   [ 0.1  0.0 -0.0]
-   [ 0.1  0.0 -0.1]
-   [ 0.0  0.1  0.0]
-   [-0.1 -0.0 -0.0]
-   [ 0.1  0.0  0.1]
-   [ 0.0  0.0  0.1]
-   [-0.1 -0.1  0.0]
-   [ 0.1  0.0 -0.0]
-   [ 0.1  0.0 -0.0]
-   [ 0.0  0.0 -0.1]
-   [-0.1 -0.0  0.0]
-   [ 0.1  0.0 -0.1]
-   [ 0.0 -0.1  0.1]
-   [-0.1 -0.1  0.0]
-   [-0.0 -0.0  0.1]
-   [ 0.0 -0.1  0.1]
-   [ 0.0  0.0 -0.1]
-   [ 0.0 -0.0  0.1]
-   [-0.1 -0.0 -0.0]
-   [ 0.1  0.0  0.1]
-   [ 0.1  0.0  0.0]
-   [ 0.1  0.1 -0.1]
-   [ 0.1  0.0  0.0]
-   [ 0.1  0.0 -0.0]
-   [ 0.0 -0.1  0.1]
-   [-0.0 -0.0  0.1]
-   [-0.1 -0.1  0.0]
-   [ 0.1  0.0  0.0]
-   [ 0.1  0.0 -0.0]
-   [ 0.1  0.0  0.0]
-   [-0.1 -0.1  0.0]
-   [ 0.0  0.0 -0.1]
-   [-0.0 -0.1  0.1]
-   [-0.1 -0.0  0.0]
-   [-0.1 -0.1  0.0]
-   [-0.1 -0.0  0.0]
-   [-0.0  0.0 -0.1]
-   [-0.1 -0.1 -0.0]
-   [-0.1 -0.0 -0.0]
-   [-0.0  0.0 -0.1]
-   [-0.0  0.1 -0.1]
-   [ 0.1  0.0  0.0]
-   [ 0.0  0.0 -0.1]
-   [ 0.0  0.0 -0.1]
-   [ 0.0  0.0 -0.1]
-   [ 0.1  0.0 -0.0]
-   [ 0.1  0.0  0.0]
-   [ 0.0  0.0  0.1]
-   [ 0.0  0.0 -0.1]
-   [-0.1 -0.0 -0.0]
-   [ 0.1  0.0  0.1]
-   [ 0.1  0.0 -0.1]
-   [ 0.1  0.0 -0.0]
-   [ 0.0 -0.1  0.1]
-   [-0.1  0.0  0.0]
-   [ 0.1  0.0  0.0]
-   [ 0.1 -0.0 -0.0]
-   [ 0.0 -0.1  0.1]
-   [ 0.0  0.0 -0.1]
-   [-0.1 -0.0  0.1]
-   [ 0.1  0.0  0.0]
-   [ 0.0 -0.0  0.1]
-   [ 0.1  0.1  0.1]
-   [ 0.0 -0.0  0.1]
-   [-0.0 -0.0  0.1]
-   [ 0.0 -0.1  0.1]
-   [ 0.0  0.0 -0.1]
-   [ 0.1 -0.0  0.1]
-   [-0.1 -0.1 -0.0]
-   [-0.0 -0.0  0.1]
-   [ 0.0  0.0 -0.1]
-   [ 0.1  0.0  0.0]
-   [-0.1  0.0  0.0]
-   [-0.1 -0.0 -0.0]
-   [-0.1 -0.0  0.0]
-   [ 0.1  0.1 -0.1]]
-# ---
-# name: test_read_oxdna.6
-  [[ 9.5e-03  1.7e-02  1.3e-02]
-   [ 1.4e-02  4.2e-02  2.6e-02]
-   [ 3.8e-02  2.7e-02  1.1e-01]
-   [ 1.8e-02 -1.1e-02  5.3e-03]
-   [ 3.3e-02 -5.0e-02  1.6e-02]
-   [-1.0e-02  2.1e-02  1.1e-02]
-   [ 2.7e-03 -1.4e-02 -1.1e-03]
-   [-1.0e-02 -6.8e-02  4.5e-03]
-   [-1.5e-02  3.7e-02  1.0e-02]
-   [-4.7e-03 -9.1e-03 -3.0e-02]
-   [ 5.3e-02  2.6e-02 -1.1e-02]
-   [ 5.0e-02 -2.7e-02 -2.0e-02]
-   [ 3.1e-02  2.5e-02  1.7e-02]
-   [ 3.2e-04  1.1e-02 -3.1e-02]
-   [ 1.0e-02  2.4e-02  3.0e-03]
-   [-5.5e-03 -7.8e-03  2.2e-03]
-   [ 3.0e-03  2.6e-02  2.3e-02]
-   [-6.1e-03  1.8e-02  1.6e-03]
-   [ 1.7e-02  3.8e-02 -1.2e-03]
-   [-1.9e-03 -9.6e-04 -1.0e-02]
-   [ 1.4e-02  3.0e-02 -3.1e-02]
-   [ 5.5e-02  2.7e-02 -1.6e-03]
-   [ 4.8e-02 -5.3e-03 -1.5e-02]
-   [ 7.9e-04  2.7e-02  2.7e-02]
-   [ 5.5e-02  2.7e-02 -1.6e-03]
-   [-4.9e-03  1.8e-02  4.4e-05]
-   [-2.0e-02  1.3e-02  3.4e-02]
-   [ 5.2e-03 -2.5e-02 -9.8e-03]
-   [ 3.8e-02  2.9e-02 -1.4e-02]
-   [-3.6e-02 -3.1e-03  5.8e-03]
-   [ 3.2e-04  1.1e-02 -3.1e-02]
-   [ 5.9e-03  1.9e-02  4.2e-02]
-   [-6.1e-03  1.8e-02  1.6e-03]
-   [-2.2e-02 -1.9e-02  6.9e-02]
-   [ 7.2e-02 -3.0e-02 -1.7e-02]
-   [-4.9e-03  1.8e-02  4.4e-05]
-   [ 3.1e-02  2.5e-02  1.7e-02]
-   [ 3.2e-04  1.1e-02 -3.1e-02]
-   [-7.3e-02  1.3e-02 -2.1e-02]
-   [ 1.9e-03  9.0e-03  3.5e-02]
-   [-5.7e-04  3.9e-03 -1.7e-02]
-   [ 2.0e-02 -5.2e-02  1.8e-02]
-   [ 3.0e-02  1.9e-02 -2.1e-04]
-   [ 1.7e-02  5.7e-04  6.4e-02]
-   [-2.4e-02 -2.9e-02 -1.2e-02]
-   [ 2.2e-02  1.9e-02  6.3e-03]
-   [-4.4e-02 -3.5e-02 -5.4e-02]
-   [ 5.5e-02  2.7e-02 -1.6e-03]
-   [ 1.9e-03  9.0e-03  3.5e-02]
-   [-1.3e-02 -1.3e-02 -3.7e-02]
-   [ 3.2e-04  1.1e-02 -3.1e-02]
-   [ 8.2e-03  4.7e-03 -4.0e-02]
-   [ 1.4e-02  3.0e-02 -3.1e-02]
-   [-2.3e-02  2.3e-02  1.6e-02]
-   [ 3.2e-04  1.1e-02 -3.1e-02]
-   [ 8.4e-03 -1.5e-02 -2.7e-02]
-   [ 3.8e-02  2.7e-02  1.1e-01]
-   [ 2.2e-02  1.5e-02  1.4e-02]
-   [ 4.6e-03 -1.7e-02  1.3e-02]
-   [ 6.3e-02  3.8e-02  5.4e-02]
-   [-3.9e-02 -9.4e-03 -3.1e-02]
-   [ 1.7e-02  3.8e-02 -1.2e-03]
-   [ 9.9e-03  2.4e-02  1.7e-02]
-   [-3.9e-02 -9.4e-03 -3.1e-02]
-   [ 2.9e-02  9.3e-04  1.7e-02]
-   [ 4.1e-03 -1.6e-02 -4.5e-02]
-   [-1.5e-02  3.7e-02  1.0e-02]
-   [ 8.4e-03 -1.5e-02 -2.7e-02]
-   [-1.6e-02 -5.1e-03  1.2e-02]
-   [ 5.9e-03  1.9e-02  4.2e-02]
-   [ 6.2e-02  4.2e-03  2.4e-02]
-   [-3.6e-02 -3.1e-03  5.8e-03]
-   [ 1.7e-02 -3.6e-02 -1.8e-02]
-   [-1.8e-03 -3.2e-02  3.8e-03]
-   [ 4.8e-02 -5.3e-03 -1.5e-02]
-   [-1.5e-02  3.4e-02  4.0e-02]
-   [-6.1e-03  1.8e-02  1.6e-03]
-   [ 3.1e-02  2.5e-02  1.7e-02]
-   [-2.3e-02 -3.0e-02  5.5e-03]
-   [-4.4e-02 -3.5e-02 -5.4e-02]
-   [-1.1e-02 -1.8e-02 -1.0e-02]
-   [ 3.1e-02  2.5e-02  1.7e-02]
-   [-2.2e-02 -1.9e-02  6.9e-02]
-   [ 2.0e-03  1.5e-02  6.5e-02]
-   [-2.4e-02 -2.9e-02 -1.2e-02]
-   [-1.9e-03 -9.6e-04 -1.0e-02]
-   [ 1.6e-02 -7.0e-03  2.8e-02]
-   [ 2.0e-02 -5.2e-02  1.8e-02]
-   [-2.1e-02  1.1e-02  4.4e-02]
-   [ 3.1e-02  2.5e-02  1.7e-02]
-   [-1.6e-02 -5.1e-03  1.2e-02]
-   [ 1.0e-02  2.4e-02  3.0e-03]
-   [ 1.7e-02  3.8e-02 -1.2e-03]
-   [-1.3e-02 -1.3e-02 -3.7e-02]
-   [ 3.3e-02 -5.0e-02  1.6e-02]
-   [ 1.8e-02 -1.1e-02  5.3e-03]
-   [-3.3e-03 -5.2e-02  6.3e-03]
-   [-5.4e-04  4.0e-02 -1.4e-02]
-   [ 5.5e-02 -3.0e-02 -2.1e-02]
-   [ 2.2e-02  1.9e-02  6.3e-03]]
-# ---
-# name: test_read_oxdna.7
-  [[ 0.0  0.3  0.0]
-   [-0.1  0.1  0.4]
-   [-0.0 -0.5  0.5]
-   [-0.2  0.1  0.2]
-   [-0.1  0.1  0.3]
-   [ 0.0  0.3  0.2]
-   [ 0.3 -0.4  0.2]
-   [-0.2  0.4  0.0]
-   [ 0.1 -0.3  0.0]
-   [ 0.7 -0.1  0.5]
-   [-0.4 -0.2 -1.1]
-   [ 0.2 -0.2  0.0]
-   [ 0.1 -0.2  0.0]
-   [ 0.1  0.4 -0.4]
-   [ 0.2 -0.3  0.4]
-   [-0.0 -0.0  0.4]
-   [-0.0 -0.2  0.1]
-   [ 0.1  0.2  0.2]
-   [ 0.0  0.2  0.4]
-   [-0.1  0.0  0.2]
-   [ 0.5  0.1  0.1]
-   [ 0.2 -0.2  0.4]
-   [ 0.5 -0.4 -0.2]
-   [-0.3  0.6  0.5]
-   [ 0.2 -0.2  0.4]
-   [-0.6  0.1 -0.1]
-   [-0.3  0.0  0.5]
-   [ 0.3 -0.4  0.4]
-   [-0.2 -0.1 -0.2]
-   [-0.3 -0.3 -0.2]
-   [ 0.1  0.4 -0.4]
-   [ 0.1 -0.2 -0.0]
-   [ 0.1  0.2  0.2]
-   [ 0.3 -0.2 -0.1]
-   [ 0.3 -0.1  0.1]
-   [-0.6  0.1 -0.1]
-   [ 0.1 -0.2  0.0]
-   [ 0.1  0.4 -0.4]
-   [ 0.1  0.1  0.5]
-   [-0.1  0.4  0.3]
-   [-0.5  0.1 -0.1]
-   [ 0.4  0.3 -0.4]
-   [ 0.2  0.3 -0.0]
-   [ 0.4 -0.3  0.0]
-   [-0.3  0.7  0.1]
-   [ 0.5 -0.0 -0.2]
-   [ 0.0 -0.0  0.7]
-   [ 0.2 -0.2  0.4]
-   [-0.1  0.4  0.3]
-   [ 0.0 -0.1 -0.7]
-   [ 0.1  0.4 -0.4]
-   [ 0.3  0.1  0.6]
-   [ 0.5  0.1  0.1]
-   [-0.1 -0.1  0.2]
-   [ 0.1  0.4 -0.4]
-   [-0.6  0.1 -0.6]
-   [-0.0 -0.5  0.5]
-   [ 0.2 -0.1  0.4]
-   [ 0.0  0.5 -0.1]
-   [-0.4  0.1  0.0]
-   [ 0.1 -0.4 -0.1]
-   [ 0.0  0.2  0.4]
-   [ 0.1  0.2  0.7]
-   [ 0.1 -0.4 -0.1]
-   [-0.3 -0.0 -0.3]
-   [ 0.1 -0.5  0.2]
-   [ 0.1 -0.3  0.0]
-   [-0.6  0.1 -0.6]
-   [-0.3  0.5  0.1]
-   [ 0.1 -0.2 -0.0]
-   [ 0.1  0.8 -0.3]
-   [-0.3 -0.3 -0.2]
-   [-0.8  0.6 -0.2]
-   [ 0.1  0.1  0.2]
-   [ 0.5 -0.4 -0.2]
-   [-0.0  0.1 -0.2]
-   [ 0.1  0.2  0.2]
-   [ 0.1 -0.2  0.0]
-   [-0.2 -0.4  0.1]
-   [ 0.0 -0.0  0.7]
-   [-0.1  0.2  0.2]
-   [ 0.1 -0.2  0.0]
-   [ 0.3 -0.2 -0.1]
-   [ 0.2  0.0  0.1]
-   [-0.3  0.7  0.1]
-   [-0.1  0.0  0.2]
-   [-0.3 -0.4 -0.3]
-   [ 0.4  0.3 -0.4]
-   [-0.3  0.0 -0.0]
-   [ 0.1 -0.2  0.0]
-   [-0.3  0.5  0.1]
-   [ 0.2 -0.3  0.4]
-   [ 0.0  0.2  0.4]
-   [ 0.0 -0.1 -0.7]
-   [-0.1  0.1  0.3]
-   [-0.2  0.1  0.2]
-   [ 0.3 -0.0 -0.3]
-   [-0.0 -0.3 -0.1]
-   [ 0.0 -0.6  0.4]
-   [ 0.5 -0.0 -0.2]]
-# ---
-# name: test_read_oxdna.8
-  [ True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True  True  True  True  True  True  True  True  True
-    True  True  True  True]
-# ---
-# name: test_read_oxdna.9
-  [[ 39  40]
-   [550 556]
-   [378 384]
-   [ 75  81]
-   [  0   6]
-   [247 253]
-   [495 501]
-   [326 327]
-   [352 358]
-   [ 14  20]
-   [331 337]
-   [473 479]
-   [153 154]
-   [409 410]
-   [538 539]
-   [540 541]
-   [ 66  67]
-   [143 138]
-   [569 564]
-   [426 432]
-   [ 54  55]
-   [431 426]
-   [365 371]
-   [ 64  65]
-   [303 304]
-   [401 396]
-   [260 261]
-   [558 564]
-   [151 152]
-   [374 380]
-   [ 73  74]
-   [ 58  64]
-   [159 160]
-   [300 301]
-   [568 574]
-   [144 145]
-   [490 491]
-   [467 462]
-   [ 98 104]
-   [302 303]
-   [249 250]
-   [442 443]
-   [351 357]
-   [293 288]
-   [118 119]
-   [ 57  58]
-   [460 461]
-   [511 512]
-   [155 150]
-   [113 108]
-   [271 277]
-   [447 453]
-   [149 144]
-   [339 340]
-   [532 538]
-   [204 205]
-   [151 157]
-   [177 178]
-   [505 506]
-   [ 25  31]
-   [134 135]
-   [160 166]
-   [ 79  85]
-   [329 335]
-   [578 579]
-   [369 375]
-   [329 324]
-   [334 335]
-   [516 517]
-   [359 354]
-   [350 356]
-   [138 144]
-   [467 473]
-   [ 35  41]
-   [233 239]
-   [428 429]
-   [376 377]
-   [ 70  71]
-   [510 516]
-   [250 251]
-   [ 56  57]
-   [570 576]
-   [457 463]
-   [340 341]
-   [ 30  31]
-   [494 495]
-   [435 436]
-   [501 507]
-   [339 345]
-   [399 400]
-   [ 49  50]
-   [141 142]
-   [432 438]
-   [511 517]
-   [580 586]
-   [196 202]
-   [ 97 103]
-   [537 538]
-   [126 127]
-   [262 263]]
+# name: TestOXDNAReading.test_univ_snapshot.3
+  [1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2
+   2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3
+   3 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4]
 # ---
diff --git a/tests/__snapshots__/test_load.ambr b/tests/__snapshots__/test_load.ambr
index 5e82b38e..e410b4aa 100644
--- a/tests/__snapshots__/test_load.ambr
+++ b/tests/__snapshots__/test_load.ambr
@@ -385,25 +385,22 @@
    [ 3.3e-01  8.1e-02  9.6e-02]]
 # ---
 # name: test_pdb_no_bonds
-  [[ 0.0  0.0  0.0]
-   [ 0.0  0.0  0.0]
-   [ 0.0  0.0  0.0]
-   [ 0.0  0.0  0.0]
-   [ 0.0  0.0  0.0]
-   [ 0.1  0.1  0.1]
-   [ 0.1  0.1  0.1]
-   [ 0.1  0.1  0.1]
-   [ 0.1  0.1  0.1]
-   [-0.0 -0.0 -0.0]
-   [-0.0 -0.0 -0.0]
-   [-0.0 -0.0 -0.0]
-   [-0.0 -0.0 -0.0]
-   [-0.0 -0.0 -0.0]
-   [-0.1 -0.1 -0.1]
-   [-0.1 -0.1 -0.1]]
-# ---
-# name: test_pdb_no_bonds.1
-  []
+  array([[ 0.01,  0.01,  0.01],
+         [ 0.02,  0.02,  0.02],
+         [ 0.03,  0.03,  0.03],
+         [ 0.04,  0.04,  0.04],
+         [ 0.05,  0.05,  0.05],
+         [ 0.06,  0.06,  0.06],
+         [ 0.07,  0.07,  0.07],
+         [ 0.08,  0.08,  0.08],
+         [ 0.09,  0.09,  0.09],
+         [-0.01, -0.01, -0.01],
+         [-0.02, -0.02, -0.02],
+         [-0.03, -0.03, -0.03],
+         [-0.04, -0.04, -0.04],
+         [-0.05, -0.05, -0.05],
+         [-0.06, -0.06, -0.06],
+         [-0.07, -0.07, -0.07]])
 # ---
 # name: test_rcsb_nmr[False]
   [[ 0.1  0.0 -0.1]
diff --git a/tests/data/oxdna/top_new_custom.top b/tests/data/oxdna/top_new_custom.top
new file mode 100644
index 00000000..12dcb175
--- /dev/null
+++ b/tests/data/oxdna/top_new_custom.top
@@ -0,0 +1,3 @@
+12 2 5->3
+GT(13)GCG type=DNA
+CGC(-10)AC type=DNA
\ No newline at end of file
diff --git a/tests/data/oxdna/traj_old_new.dat b/tests/data/oxdna/traj_old_new.dat
new file mode 100644
index 00000000..c8a1aad7
--- /dev/null
+++ b/tests/data/oxdna/traj_old_new.dat
@@ -0,0 +1,30 @@
+t = 500000
+b = 17 17 17
+E = -1.26125121116638 -1.40279078483582 0.141539588570595
+-2.71388244628906 3.47911643981934 6.11712265014648 0.623006105422974 0.782013833522797 -0.0178236979991198 -0.00681409984827042 -0.0173595044761896 -0.99982613325119 -0.104749746620655 0.207955867052078 0.110502049326897 0.0185949858278036 0.337806850671768 0.245974078774452
+-2.84630966186523 3.69316101074219 5.7212028503418 0.966981947422028 0.254525274038315 0.0127692595124245 -0.0131023805588484 0.0996926948428154 -0.994932115077972 0.212986201047897 0.339831411838531 0.082770824432373 -0.713768541812897 -0.0234667118638754 0.0252062696963549
+-2.82102584838867 4.00576019287109 5.30809211730957 0.932236790657043 -0.350077509880066 -0.0915448889136314 -0.0169287864118814 0.210519894957542 -0.977442979812622 -0.385900378227234 -0.0936472117900848 -0.313209593296051 0.060018464922905 -0.358485043048859 -0.125160396099091
+-2.70832443237305 4.34485244750977 4.95480155944824 0.624891877174377 -0.771166145801544 -0.121707588434219 0.0888340398669243 0.225115388631821 -0.970273911952972 0.527467906475067 0.261296689510345 -0.110662423074245 -0.435533821582794 -0.157417297363281 -1.07367062568665
+-2.3138313293457 4.62926292419434 4.59322357177734 0.261396735906601 -0.963984310626984 -0.0490521043539047 0.337246656417847 0.13882876932621 -0.931123673915863 -0.00569585803896189 0.0389907471835613 -0.169724598526955 -0.452835589647293 0.0985835194587708 -0.0695057287812233
+-1.86847686767578 4.6140079498291 4.27702713012695 -0.44191586971283 -0.887813329696655 -0.128443613648415 0.188339829444885 0.0481664389371872 -0.980922043323517 0.221844404935837 -0.153715997934341 0.626589596271515 -0.184030756354332 0.109232373535633 -0.243071481585503
+-1.54825973510742 4.52231025695801 3.97049713134766 -0.898629486560822 -0.346900135278702 -0.268561482429504 0.242089331150055 0.118410050868988 -0.963001430034637 0.327147036790848 -0.497938275337219 0.155039936304092 -0.0512844771146774 0.0948343500494957 0.28431835770607
+-1.39173126220703 4.39387130737305 3.42015838623047 -0.980471789836884 0.158813059329987 -0.115989819169044 0.132955610752106 0.100710794329643 -0.985992014408112 -0.220508337020874 -0.185717165470123 0.685320019721985 0.323797792196274 -0.220896035432816 -0.104263804852962
+-1.35349273681641 4.16534996032715 2.97673606872559 -0.800813436508179 0.598714113235474 0.0154705159366131 0.00132620707154274 0.0276035778224468 -0.999618053436279 -0.00249419989995658 -0.22495037317276 0.350358664989471 0.214432939887047 0.232472226023674 0.32265642285347
+-1.60685729980469 4.05478477478027 2.47950744628906 -0.194842725992203 0.94876229763031 0.248769581317902 0.109083957970142 0.273018062114716 -0.955804228782654 0.167082190513611 -0.359410494565964 -0.178383335471153 -0.824753701686859 0.637020826339722 -0.167981579899788
+-1.91200256347656 4.21942138671875 1.97663497924805 0.379594355821609 0.804162502288818 0.457417547702789 0.203989282250404 0.40950345993042 -0.88921046257019 -0.00431415066123009 0.0244927313178778 -0.116692334413528 0.125121146440506 0.595021784305573 0.56517106294632
+-1.58051300048828 3.00995254516602 0.902116775512695 -0.178838655352592 0.198652476072311 -0.963615119457245 0.977483808994293 0.147357195615768 -0.151034310460091 -0.476231455802917 0.662693500518799 -0.170812621712685 -0.542614102363586 0.0206559374928474 0.0502250045537949
+t = 1000000
+b = 17 17 17
+E = -1.22928142547607 -1.36916053295135 0.139879152178764
+7.46204137802124 7.52110433578491 7.83010578155518 -0.853093445301056 0.426008105278015 -0.301245599985123 -0.227878659963608 -0.823602437973022 -0.519375205039978 -0.332762956619263 -0.317888766527176 0.282985895872116 -0.353773027658463 -0.669774651527405 0.484911501407623
+7.21830224990845 7.0861120223999 7.7243504524231 -0.528895139694214 0.625599324703217 -0.573493957519531 -0.409386813640594 -0.779989540576935 -0.473306149244308 0.151937931776047 -0.167389675974846 -0.14412122964859 0.279533714056015 0.157498434185982 -0.317104578018188
+6.75138759613037 6.81209516525269 7.7138819694519 -0.115494772791862 0.383829653263092 -0.916152715682983 -0.408844739198685 -0.858943819999695 -0.30832052230835 0.309087634086609 0.212393179535866 0.0225550550967455 0.156060591340065 0.423906028270721 -0.265006899833679
+6.34469318389893 6.58345937728882 7.48868465423584 0.632181882858276 0.0849567949771881 -0.77014821767807 -0.432633817195892 -0.785887837409973 -0.441823750734329 -0.637137830257416 0.113170854747295 0.0633947029709816 0.202342167496681 -0.0456349290907383 -0.13218092918396
+6.08737134933472 6.2936577796936 7.19296026229858 0.820043802261353 0.0645908638834953 -0.568644106388092 -0.435493439435959 -0.574235141277313 -0.693252742290497 0.0720811188220978 0.19222217798233 0.11419240385294 0.205475464463234 -0.0490295737981796 0.0106330988928676
+5.9496488571167 6.22579193115234 6.71777057647705 0.914512693881989 -0.371278703212738 -0.160681933164597 -0.35827162861824 -0.558784961700439 -0.747931063175201 0.614271342754364 -0.0999471619725227 0.361342281103134 0.0820026695728302 -0.355395525693893 -0.028274804353714
+6.03442049026489 6.15534734725952 6.20938539505005 0.597340881824493 -0.71271675825119 0.36772084236145 -0.176585033535957 -0.56414407491684 -0.806572437286377 0.201110288500786 -0.0539062209427357 -0.169853910803795 0.221071720123291 -0.00261460873298347 0.186809182167053
+6.31864213943481 6.01393890380859 5.74865531921387 -0.00441425293684006 -0.795202493667603 0.606327891349792 -0.164589241147041 -0.597486793994904 -0.784805655479431 0.126673400402069 -0.333357959985733 -0.693504929542542 -0.680877029895782 0.0207977201789618 -0.0766764506697655
+6.39327239990234 5.57877922058105 5.39767599105835 -0.169323325157166 -0.566127598285675 0.806739985942841 -0.242910355329514 -0.769335150718689 -0.590862274169922 -0.0956622660160065 0.0371962748467922 0.139915153384209 0.0668022334575653 0.27230516076088 -0.415111631155014
+6.51349687576294 5.13402462005615 5.28965139389038 -0.83998566865921 -0.0992453396320343 0.5334552526474 -0.211517080664635 -0.845468461513519 -0.49035057425499 0.143512487411499 -0.734968781471252 0.625438094139099 -0.504727780818939 0.427298992872238 0.396458148956299
+6.48263263702393 4.60228633880615 5.25323915481567 -0.928756654262543 0.336657911539078 0.155153423547745 -0.369067341089249 -0.800676763057709 -0.471917301416397 0.556943237781525 0.18658272922039 0.303757041692734 0.0550393797457218 -0.197236597537994 0.301765143871307
+7.78814792633057 4.3724536895752 4.33855724334717 0.794353783130646 -0.602611839771271 -0.0765565186738968 0.0845730304718018 0.234512984752655 -0.968427062034607 -0.803858280181885 0.203380703926086 -0.433198422193527 0.0429709292948246 0.275111734867096 -0.058091577142477
diff --git a/tests/test_dna.py b/tests/test_dna.py
index 58236a93..f0c37bc7 100644
--- a/tests/test_dna.py
+++ b/tests/test_dna.py
@@ -1,59 +1,97 @@
-import numpy as np
-import molecularnodes as mn
+import pytest
+import MDAnalysis as mda
 from molecularnodes.entities.trajectory import dna
-from .utils import sample_attribute, NumpySnapshotExtension
+from .utils import NumpySnapshotExtension
 from .constants import data_dir
 
 
-def test_read_topology():
-    file_new = data_dir / "oxdna/top_new.top"
-    file_old = data_dir / "oxdna/top_old.top"
-
-    arr_old = dna.toplogy_to_bond_idx_pairs(dna.read_topology_old(file_old))
-    arr_new = dna.toplogy_to_bond_idx_pairs(dna.read_topology_new(file_new))
-
-    assert np.array_equal(arr_old, arr_new)
-
-
-def test_topology_to_idx():
-    top = np.array([[1, 31, -1, 1], [1, 3, 0, 1], [1, 2, 1, -1]])
-
-    bonds = dna.toplogy_to_bond_idx_pairs(top)
-    expected = np.array([[0, 1], [1, 2]])
-
-    assert np.array_equal(bonds, expected)
-
-
-def test_base_lookup():
-    bases = np.array(["A", "C", "C", "G", "T", "-10", "G", "C", "-3"])
-    expected = np.array([30, 31, 31, 32, 33, -1, 32, 31, -1])
-
-    ints = dna.base_to_int(bases)
-
-    assert np.array_equal(ints, expected)
-
-
-def test_read_trajectory():
-    traj = dna.read_trajectory(data_dir / "oxdna/holliday.dat")
-
-    assert traj.shape == (20, 98, 15)
-
-
-def test_read_oxdna(snapshot_custom: NumpySnapshotExtension):
-    name = "holliday"
-    mol, coll_frames = dna.load(
-        top=data_dir / "oxdna/holliday.top",
-        traj=data_dir / "oxdna/holliday.dat",
-        name=name,
-    )
-
-    assert len(coll_frames.objects) == 20
-    assert mol.name == name
-
-    for att in mol.data.attributes.keys():
-        assert snapshot_custom == sample_attribute(mol, att)
-
-    # realise all of the geometry and sample some attributes
-    mn.blender.nodes.realize_instances(mol)
-    for att in mol.data.attributes.keys():
-        assert snapshot_custom == sample_attribute(mol, att, evaluate=True)
+class TestOXDNAReading:
+    @pytest.fixture(scope="module")
+    def filepath_top(self):
+        return data_dir / "oxdna/holliday.top"
+
+    @pytest.fixture(scope="module")
+    def filepath_top_new(self):
+        return data_dir / "oxdna/top_new.top"
+
+    @pytest.fixture(scope="module")
+    def filepath_top_new_custom(self):
+        return data_dir / "oxdna/top_new_custom.top"
+
+    @pytest.fixture(scope="module")
+    def filepath_top_old(self):
+        return data_dir / "oxdna/top_old.top"
+
+    @pytest.fixture(scope="module")
+    def filepath_traj_old_new(self):
+        return data_dir / "oxdna/traj_old_new.dat"
+
+    @pytest.fixture(scope="module")
+    def filepath_traj_dat(self):
+        return data_dir / "oxdna/holliday.dat"
+
+    @pytest.fixture(scope="module")
+    def universe(self, filepath_top, filepath_traj_dat):
+        return mda.Universe(
+            filepath_top,
+            filepath_traj_dat,
+            format=dna.OXDNAReader,
+            topology_format=dna.OXDNAParser,
+        )
+
+    def test_read_as_universe(self, filepath_top, filepath_traj_dat):
+        u = mda.Universe(
+            filepath_top,
+            filepath_traj_dat,
+            format=dna.OXDNAReader,
+            topology_format=dna.OXDNAParser,
+        )
+        assert u.atoms.n_atoms == 98
+
+    def test_univ_as_traj(self, universe):
+        traj = dna.OXDNA(universe)
+        assert traj.universe
+        assert not traj.object
+        assert all([x in ["A", "C", "T", "G"] for x in traj.res_name])
+
+    def test_univ_snapshot(self, universe: mda.Universe, snapshot_custom):
+        traj = dna.OXDNA(universe)
+        traj.create_object()
+        for name in ["position", "res_name", "res_id", "chain_id"]:
+            assert snapshot_custom == getattr(traj, name)
+
+    def test_detect_new_top(
+        self, filepath_top_old, filepath_top_new, filepath_top_new_custom
+    ):
+        assert dna.OXDNAParser._is_new_topology(filepath_top_new)
+        assert dna.OXDNAParser._is_new_topology(filepath_top_new_custom)
+        assert not dna.OXDNAParser._is_new_topology(filepath_top_old)
+
+    def test_topo_reading(
+        self,
+        filepath_top_old,
+        filepath_top_new,
+        filepath_top_new_custom,
+    ):
+        top_new = dna.OXDNAParser._read_topo_new(filepath_top_new)
+        top_new_custom = dna.OXDNAParser._read_topo_new(filepath_top_new_custom)
+        top_old = dna.OXDNAParser._read_topo_old(filepath_top_old)
+
+        for top in [top_new, top_old, top_new_custom]:
+            assert top.n_atoms == 12
+            assert top.n_residues == 12
+
+    @pytest.mark.parametrize("topfile", ["top_new", "top_new_custom", "top_old"])
+    def test_comparing_topologies(self, snapshot, topfile, filepath_traj_old_new):
+        u = mda.Universe(
+            data_dir / f"oxdna/{topfile}.top",
+            filepath_traj_old_new,
+            topology_format=dna.OXDNAParser,
+            format=dna.OXDNAReader,
+        )
+        traj = dna.OXDNA(u)
+        traj.create_object()
+        assert len(traj) == 12
+        assert snapshot == traj.bonds.tolist()
+        for att in ["res_id", "chain_id", "res_name"]:
+            assert snapshot == traj.named_attribute(att).tolist()
diff --git a/tests/test_load.py b/tests/test_load.py
index bf808232..1dfa014a 100644
--- a/tests/test_load.py
+++ b/tests/test_load.py
@@ -127,10 +127,11 @@ def test_local_pdb(snapshot_custom):
         for mol in molecules:
             assert snapshot_custom == sample_attribute(mol, att, evaluate=False)
 
-def test_pdb_no_bonds(snapshot_custom):
-    molecule = mn.entities.load_local(data_dir / f"no_bonds.pdb", style="spheres")
-    for attr in ["position",  "bond_type"]:
-        assert snapshot_custom == sample_attribute(molecule, attr, evaluate=False)
+
+def test_pdb_no_bonds(snapshot):
+    mol = mn.entities.load_local(data_dir / "no_bonds.pdb", style=None)
+    assert len(mol.object.data.edges) == 0
+    assert snapshot == mol.position
 
 
 @pytest.mark.parametrize("del_hydrogen", [True, False])
diff --git a/tests/test_ops.py b/tests/test_ops.py
index a05b7cef..52753ad6 100644
--- a/tests/test_ops.py
+++ b/tests/test_ops.py
@@ -20,7 +20,7 @@ def test_op_api_cartoon(
     scene = bpy.context.scene
     scene.MN_import_node_setup = True
     scene.MN_pdb_code = code
-    scene.MN_import_style = style
+    scene.mn.import_style = style
     scene.MN_import_node_setup = True
     scene.MN_import_build_assembly = False
     scene.MN_import_centre = False
@@ -47,7 +47,7 @@ def test_op_api_cartoon(
 def test_op_local(snapshot_custom, code, file_format):
     scene = bpy.context.scene
     scene.MN_import_node_setup = False
-    scene.MN_import_style = "spheres"
+    scene.mn.import_style = "spheres"
     scene.MN_import_build_assembly = False
     scene.MN_import_del_solvent = False
     scene.MN_import_format_download = file_format
@@ -81,7 +81,7 @@ def test_op_api_mda(snapshot_custom: NumpySnapshotExtension):
 
     bpy.context.scene.MN_import_md_topology = topo
     bpy.context.scene.MN_import_md_trajectory = traj
-    bpy.context.scene.MN_import_style = "ribbon"
+    bpy.context.scene.mn.import_style = "ribbon"
 
     with ObjectTracker() as o:
         bpy.ops.mn.import_trajectory()
@@ -90,6 +90,7 @@ def test_op_api_mda(snapshot_custom: NumpySnapshotExtension):
     assert obj_1.name == name
 
     traj = mn.entities.trajectory.load(topo, traj, name="test", style="ribbon")
+    traj.subframes = 0
     obj_2 = traj.object
 
     for mol in [obj_1, obj_2]: