On May 7, 2025, at 2:01 AM, Mühleip, Alexander <alexander.muhleip@helsinki.fi> wrote:

Hi Elaine,

I am checking out the new kvfinder tool in ChimeraX. I was wondering if there is some way to prevent it from disregarding heteroatoms in the cavity search (in my eyes, e.g. excluding hemes is not helpful). I tried changing the selection syntax, but I think the pruning is taking place internally in kvfinder.

Is there some way to interfere with it or make an ignore option (like the isolde implementation in chimerax has)?

Best wishes, Alex

Alexander Mühleip group leader HiLIFE-Institute of Biotechnology University of Helsinki Finland +358503282167

Hi Alex, Generally it's better to ask on the chimerax-users list, since as the resident non-programmer I often don't know implementation details. I CC'd the list in case others may also be interested in this topic. After consultation with the programmer who implemented this tool, we could not think of any current workaround. It uses the "main" category of atoms (definition in link below) which is automatically assigned cannot be manually overwritten. <https://rbvi.ucsf.edu/chimerax/docs/user/commands/atomspec.html#surfcats> However, we can consider this a request for enhancement that might be added in the future. Best wishes, 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