indeed! Jane Wibley used the his-tag method for the preparation of human O6-alkylguanine-DNA alkyltransferase, our "rivals" in California did not. They found a (structural) Zn ion, we did not.
see pdbs 1qnt (Wibley et al. Nucleic Acids Res, 28, p393 (2000) and 1eh6 (Daniels et al., EMBO J 19, p1719 (2000). Peter Peter Moody 1/56 Henry Wellcome Laboratories University of Leicester Lancaster Road Leicester LE1 9HN UK tel. (0)116 229 7097 fax. (0)116 229 7084 ________________________________ From: CCP4 bulletin board [EMAIL PROTECTED] On Behalf Of Jacob Keller [EMAIL PROTECTED] Sent: 18 July 2008 01:03 To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] Imidazole's ability to chelate metal ions Dear Crystallographers, Does anybody happen to know whether imidazole is able to chelate metal ions in solution? It seems reasonable that since it can compete for binding to IMAC resins, it should have some affinity for at least Ni++ and Co++, but what about metal ions like Ca++ and Mg++? I assume that the affinity is weak, but at the concentrations at which we are wont to use it in our elutions (~100-500 mM), does it not seem likely that other metal ions are being competed away from our proteins as well? Jacob Keller ******************************************* Jacob Pearson Keller Northwestern University Medical Scientist Training Program Dallos Laboratory F. Searle 1-240 2240 Campus Drive Evanston IL 60208 lab: 847.491.2438 cel: 773.608.9185 email: [EMAIL PROTECTED]<mailto:[EMAIL PROTECTED]> *******************************************
