Maia I took a look at the PDB entry 3C9E. The covalently bound ligand can be taken care of using the CIF link files. The chain of sugars is a different matter. There is a LINK to a symmetry copy such that the chain continues into the next ASU forming an infinite chain. I've started working on code to generate the needed files for refinement. If you need the files today, I can generated them with my test code and you can use them with the current version of PHENIX. Is the sugar chain the same as in 3C9E? Nigel -- Nigel W. Moriarty Building 64R0246B, Physical Biosciences Division Lawrence Berkeley National Laboratory Berkeley, CA 94720-8235 Phone : 510-486-5709 Fax : 510-486-5909 Email : [email protected] Web : CCI.LBL.gov