Generating symmetry mates

PDB files often provide very interesting information on how proteins are organized in their crystal structure and biological assembly.

The Symmetry Mate Editor Extension helps to generate symmetric replicas of a protein based on the information contained in a PDB file. To add the Symmetry Mate Editor Extension to your SAMSON, sign in on SAMSON Connect and click the 'Add' button on the extension page. Then, simply restart your SAMSON to have the extension automatically installed.

Once in SAMSON, use the top search box (Shift+E) to find the editor or access it via the left-side menu in the viewport (... > General > Symmetry Mate Editor):

Find the editor

When this editor is selected, control nodes appear in the viewport.

Use Ctrl/Cmd + mouse wheel to see more or fewer of these control nodes. Here is an example with 1BRE:

Symmetry Mate - Wheel

When the mouse moves overĀ a control node, a preview of the corresponding replica is shown:

Preview

By left clicking on a control node, the replica is created. This way, in a few clicks, you can generate a complex structure:

Undo

This editor handles CRYST1 (white widgets) and BIOMT (yellow widget) records.

Switch from one to the other with the editor GUI. Here is an example with 1B5S:

CRYST1 and BIOMT symmetries

To preview and create all replicas simultaneously, press and hold Ctrl/Cmd before hovering and left-clicking a control node:

Replicas

If you have any questions or feedback, please use the SAMSON forum.