Dear Andy, There is a "language" for specifying atoms, residues, chains, models in commands. For example: delete #0:10-20.a,12.b,40.b (delete residues 10-20 in chain A and residues 12 and 40 in chain B, all in model 0) ~ribbon #0:312-456 (hide ribbon for residues 312-456 in all chains of model 0) ~disp :.a (undisplay atoms/bonds for chain A in all models) There are many fancier things you can do, including distance zones, etc., and it is all documented: <http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/midas/ frameatom_spec.html> There are also some examples of command-line specifications on the second page of the Quick Ref: <http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/quickref.pdf> Another more graphical possibility is to show the sequences of the various chains (Favorites... Sequence) and select parts of those, then use the Actions menu to delete atoms/bonds, or hide atoms/bonds, or hide ribbons. I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. meng@cgl.ucsf.edu UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco http://www.cgl.ucsf.edu/home/meng/index.html On Jun 2, 2009, at 11:22 PM, Anindito Sen wrote:

Dear All I have a Chimera session in which I have 6 sets of PDB files (ribbon representation) showing variability in the structures. However I wish to display only few of the subunits. Questions are:

1. How do I delete undesired subunits from all the chains on the command line

2. How do I select particular residues from specific chains (not all the 6). Thanks Andy