[ccp4bb]

Dear all, I am now determining a structure at 2.2 A resolution. The space group is C2, and there is only one molecular in an ASU. During the refinement, some weird electron density appears right on the two-fold axis. Does anyone have any idea what could this be? Thanks a lot. Best regards

[ccp4bb] Weird electron density on the two-fold axis

Dear all, I am now determining a structure at 2.2 A resolution. The space group is C2, and there is only one molecular in an ASU. During the refinement, some weird electron density appears right on the two-fold axis. Does anyone have any idea what could this be? Thanks a lot. Best regards

Re: [ccp4bb] Nucleophilic attack by the side-chain carboxyl group of Asp?

] *On Behalf Of *Crystal Xu *Sent:* 20 July 2012 06:32 *To:* CCP4BB@JISCMAIL.AC.UK *Subject:* [ccp4bb] Nucleophilic attack by the side-chain carboxyl group of Asp? ** ** Hi everyone, I am studying the catalytic mechanism of an enzyme. My structural data indicates that an Asp

[ccp4bb] Nucleophilic attack by the side-chain carboxyl group of Asp?

Hi everyone, I am studying the catalytic mechanism of an enzyme. My structural data indicates that an Asp is of most possibility to sever as a general base. The Asp residue is coordinated to a zinc ion. Would it be possible that the side-chain carboxyl group of Asp attacks a carbon atom of the