![](https://secure.gravatar.com/avatar/36805688f62b2698e4f2ca741067f676.jpg?s=120&d=mm&r=g)
Greetings, I have a co-crystal structure of a protein bound to an interesting polymer -- poly-D-g-glutamic acid (poly glutamic acid with D chirality and gamma linked, rather than alpha linked). In the structure, I have density corresponding to different links, from 1 to 6 (so far). I'd like to build a ligand that has "residues" much like a polypeptide polymer so that I can refine each residue individually (hopefully in COOT). Up till now, I've been using SMILES to generate the different length polymers so I have pdbs and cif files, and then (painstakingly) modelling them into COOT, building restraints for refinement, etc. More recently, I used maestro to build a dimer that at least has the right atom labels you'd expect for a protein. However, I can't use phenix now to generate cif files because it is confused by the GLU. Is there a way to use phenix.elbow to make a multi-residue polymer? I'm also doing some monte carlo minimizations in macromodel to generate models of the various low energy states and would like to use them as building blocks, so an easy order-of-operations would be to generate the files in macromodel and feed them in via pdbs to phenix.elbow to generate cif restraints. Any help on this would be greatly appreciated. Cheers, Geoff -- Geoffrey K. Feld Department of Chemistry 492 Stanley Hall University of California, Berkeley "Vigilia pretium libertatis"