Looks like oxalate with two water molecules nearby. Oxalate is a fairly common product of PEG oxidation.
Artem --- When the Weasel comes to give New Year's greetings to the Chickens no good intentions are in his mind. -----Original Message----- From: CCP4 bulletin board [mailto:[email protected]] On Behalf Of Abhinav Kumar Sent: Thursday, April 02, 2009 1:51 PM To: [email protected] Subject: Re: [ccp4bb] Identifying an unknown ligand Some more info about this structure: Crystallization conditions: Glycerol, 0.1700M NaOAc, 25.5000% PEG-4000, 0.1M TRIS pH 8.5 This does not sit on any crystalllographic symmetry axis. But it sits right between two monomers and the NCS 2-fold axis. The protein is chemotaxis protein CheX. Environment: Some main chain amide Ns around it, as well as phobic side chains. No peak in anomalous difference fourier map. Thanks Abhinav Stanford Synchrotron Radiation Laboratory Joint Center for Structural Genomics Mail Stop 99 Phone: (650) 926-2992 Fax: (650) 926-3292 Abhinav Kumar wrote: > Hi, > > I am refining a structure and have a region of unmodeled density into > which I am trying to fit a ligand. The identity of the ligand is not > obvious, so I modeled a bunch of dummy atoms into the density. > Could you please have a look at the map and pdb files and help me > identify this ligand? > > Please see http://smb.slac.stanford.edu/~abhinavk/UNL/unl.html > > Thanks Abhinav > Stanford Synchrotron Radiation Laboratory Joint Center for Structural > Genomics Mail Stop 99 Phone: (650) 926-2992 Fax: (650) 926-3292
