Hi Ali, My colleague shared your question with me and I will try to answer it here. For the future, please send your ChimeraX questions to chimerax-users@cgl.ucsf.edu (CC'd here so you don't need to do anything this time) so that other users can benefit, unless you are including data that needs to be kept private. Sorry, ChimeraX does not calculate binding affinities (binding free energy) or predict their changes when you mutate the protein. You can only get a an approximate, first-order impression of whether they appear to improve or disrupt favorable interactions by measuring things like the surface area in the interface or the number of hydrogen bonds or clashes (bad packing) between the binding partners. See command "measure buriedarea" and the tools "Hbonds" "Contacts" and "Clashes" : <https://rbvi.ucsf.edu/chimerax/docs/user/commands/measure.html#buriedarea> <https://rbvi.ucsf.edu/chimerax/docs/user/tools/hbonds.html> <https://rbvi.ucsf.edu/chimerax/docs/user/tools/clashes.html> The picture that you get from these tools might still be incorrect if any of the 3D structures are predicted inaccurately (wrong sidechain conformations, wrong binding interface, wrong fold, etc.). I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco
From: Ali Aljasser <aljassera@cua.edu> Subject: ChimeraX- protein protein interaction parameter Date: October 5, 2023 at 5:12:46 PM PDT
I am part of Dr. Choy's group at the Catholic University of America. I work on studying the protein-protein interaction for two kinetochore proteins. Based on alpha fold prediction, we utilized Chimerax to predict the strength of the interaction of these two proteins. We also added some mutations that are known to influence the interaction. However, I still struggling with how to find parameters such as delta G that would help me to predict the strength of the interaction and whether the mutations affect the interaction.
Please let me know if you can assist me in this regard. Thank you for your time and I am looking forward to hearing from you soon. Regards, Ali