Hi, I have a system from which I only have xyz coordinates. What I would like to do is to define myself residue attribute on different fragments of the molecules. Could you tell me how (or if there is a way to ): 1. expand a selection to bonding atoms (i.e. I click on one atom and expand selection through one bond after each actions) This would be of the easiest way for me to select the fragments I want to. 2. set a residue attribute to the given selected fragment. I think I remember how to do so in scripting, but what is the command line to do so? Kind regards, JD Dr. Jean-Didier Maréchal Lecturer The Computational Biotechnological Chemistry Team Unitat de Química Física Departament de Química Universitat Autònoma de Barcelona Edifici C.n. 08193 Cerdanyola (Barcelona) Tel: +34.935814936 e-mail: JeanDidier.Marechal@uab.es www: http://asklipio.qf.uab.es