Greetings,<br><br>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&#39;d like to build a ligand that has &quot;residues&quot; much like a polypeptide polymer so that I can refine each residue individually (hopefully in COOT). Up till now, I&#39;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&#39;d expect for a protein. However, I can&#39;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&#39;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.<br>

<br>Cheers,<br>Geoff<br clear="all"><br>-- <br>Geoffrey K. Feld<br><br>Department of Chemistry<br>492 Stanley Hall<br>University of California, Berkeley<br><br>&quot;Vigilia pretium libertatis&quot;<br>