Dear ChimeraX team, First of all, many thanks for the app, it’s really wonderful!. I have a question regarding one feature I would like to have and maybe it’s possible to do but I just don’t know how. I have a PDB of the structure of an enzyme that has 5 different domains: I can select the aa of each domain and give each domain a color. This is very useful for me when comparing structure predictions of the enzyme and see what happens when making mutations in the primary structure. My problem is that I cannot save the PDB with the colors for each domain, so I have to select and assign the colors every time, or leave the app and the PDB permanently open, which is not very convenient. Is there a way to save the PDB with the modifications I made? Many thanks for your help. Best, Claudio Dr. Claudio Aguilar, PhD Virologisches Institut Universität Zürich Vetsuisse Fakultät Winterthurerstrasse 266a CH-8057 Zürich Switzerland phone: +41446358712 Fax: +41446358911