Did you confirm this mutation rigorously? Specifically do the DNA sequencing results (at least double strand sequencing) and the MS of the purified protein agree with the expected mutation?
Better be safe than sorry. Regards, Artem -----Original Message----- From: CCP4 bulletin board [mailto:[EMAIL PROTECTED] On Behalf Of HTC Sent: Wednesday, October 17, 2007 9:36 PM To: [email protected] Subject: [ccp4bb] Flexible proline? Dear all, Recently, I crystallized a mutant protein in which a Glycine was changed to Proline. The resolution of the crystal is 3.35A. I performed molecular replacement and refinement with CCP4. Surprisingly, no electronic density can be detected for the side chain of Proline. Since Proline is always considered rigid, I wonder if it is possible that this Proline is so flexible that its map becomes undetectable? The density map is attached. Thanks in advance! Tiancen Hu Shanghai Institute of Materia Medica Rm. 2107, #555, ZuChongzhi Rd. Shanghai 201203 P.R. China
