Hi everyone, As explain in the Chimera user guide, I used the command such like distance #0.2:246@N#0.5:131@N to measure the distance between two atoms of interest. To be more explicit regarding my first email, it was necessary to re-edit the pdb file and to assign a model number to each chain. In the example above, the chain B is named model 2 (then model 0.2 in Chimera) and the chain D is named model 5 (then model 0.5 in Chimera). It works fine but I suppose that there is a simpler and more direct way to specify the chain in the command? Many thanks Damien -------- Message original -------- Sujet: distance between 2 residues Date : Mon, 17 Jan 2011 18:09:11 +0100 De : Damien Larivière <damien.lariviere@fourmentinguilbert.org> Pour : chimera-users@cgl.ucsf.edu Dear all, I would like to know the (mean or approximative) distance between two residues within a protein (let's say Res 5 of chain A and Res 246 of chain C). I suppose that I have to select one atom in each of the residues and use the Distance tool. I confess I have trouble to do so, either by picking in the viewport or by using the atom identifier. May you tell me a simple way to achieve such a distance? Many thanks for your help Damien