Hi Sarma, > I can change the color of the surface to gray or a rainbow gradient > using the options but can't find a way to specify the residues that need > to be colored differently in a surface representation.
You most likely need to select the residues first. That will give you an extra entry in the right panel which you can then modify (e.g. change color). You can select specific residues via the PyMOL sequence view (Display -> View Sequence). Notice that when you select residues they are highlighted in the structure (purple dots) and you get an extra entry in the right panel. You can then change the color for those specific residues. Another way to select residues is the command (you can enter them in any of the two PyMOL windows): select <name>, selection For example: select protein_x_interaction, residue 456+874 You will then get a "protein_x_interaction" in the right panel. Ranges of residues can be selected with (notice the : between the first and last residue): select protein_y_interaction, residue 53:87 Hope this is of help to you! Kind Regards, ./ Kristoffer Denmark
