Hi Ryssa, The ChimeraX alphafold tool runs ColabFold, which is based on AlphaFold 2 and does not predict post-translational modifications. <https://rbvi.ucsf.edu/chimerax/docs/user/tools/alphafold.html> There is another ChimeraX tool that runs Boltz, which is somewhat based on AlphaFold 3. Although the Boltz program can predict post-translational modifications, however, it is a current limitation of the ChimeraX interface (tool and command) that there is no way to specify such modifications. Sorry about that. See <https://rbvi.ucsf.edu/chimerax/docs/user/tools/boltz.html> <https://rbvi.ucsf.edu/chimerax/docs/user/tools/boltz.html#limitations> I hope this clarifies the current situation, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Resource for Biocomputing, Visualization, and Informatics Department of Pharmaceutical Chemistry University of California, San Francisco
On Sep 16, 2025, at 11:16 AM, Parks, Ryssa via ChimeraX-users <chimerax-users@cgl.ucsf.edu> wrote:
Hello, I am trying to predict and model a peptide docking to a receptor protein using ChimeraX's AlphaFold interface, and I was wondering if there is any way to specify post-translational modifications in the AlphaFold input function in ChimeraX? Our peptide has an amidated C-terminus, and my searches online have not yielded much success.
Thank you, Ryssa Parks