Hi Neville, You can replace all lysine residues in a molecule with alanines using the Chimera command swapaa ALA #0:LYS The #0 refers to the molecule id number shown in model panel. Here is further documentation on swapaa. http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/midas/swapaa.html Tom yimnai forlemu wrote:

Hi Tom I have a quick question about chimera. Can you perform multi amino acid residue mutation using chimera. For example lets say you have a protein of 340 amino acids with about 100 lysine, and you want all the lysines to become say ALaninis. Is that possible Thanks Neville