Dear Mamadou, First make sure of which program you are using. You said "Chimera" but since you sent this to the ChimeraX e-mail address, I will answer for ChimeraX first. We would generally recommend that one because it is our current program and under active development. In ChimeraX, you can mutate amino acid residues with the Rotamers tool (menu: Tools... Structure Editing... Rotamers) or the "swapaa" command. See the help pages for these in the ChimeraX User Guide: <https://rbvi.ucsf.edu/chimerax/docs/user/tools/rotamers.html> <https://rbvi.ucsf.edu/chimerax/docs/user/commands/swapaa.html> Chimera also has a Rotamers tool and swapaa command, but how to use them are slightly different than in ChimeraX. If you really need to use Chimera, please see the following instead of the links above: <https://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/rotamers/framerot...> <https://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/swapaa.html> I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco

On Jun 27, 2024, at 11:02 AM, Mamadou Sangare via ChimeraX-users <chimerax-users@cgl.ucsf.edu> wrote:

Dear, I’m new in chimera and I wouldlike to know how to induce mutations in protein structure, in other words, how to replace one residue by another in the protein structure. Kind regards! Mamadou SANGARE, PhD student ACE-B,Mali