Re: [ccp4bb] CYS mod

[Boaz Shaanan]

Hi, As I've just written to David, maybe it's sulfenic acid (result of radiation damage?). I've had those in some cases. See attached scheme for the chemistry and other possibilities for Cys modification by oxidation.            Boaz     Boaz Shaanan, Ph.D.                                         Dept. of Life Sciences                                      Ben-Gurion University of the Negev                          Beer-Sheva 84105                                            Israel                                                                                                                  E-mail: bshaa...@bgu.ac.il Phone: 972-8-647-2220  Skype: boaz.shaanan                  Fax:   972-8-647-2992 or 972-8-646-1710                          From: CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] on behalf of Bio Physics [biophysics.w...@gmail.com] Sent: Tuesday, May 12, 2015 11:57 PM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] CYS mod Hi All, I have same type of modified CYS !!! No BME. On Tue, May 12, 2015 at 2:59 PM, David Schuller <schul...@cornell.edu> wrote: So far almost everyone is suggesting BME. I didn't do the purification & crystallization myself, but I am told: Buffer was HEPES cryo was ethylene glycol, glycerol and DMSO. Some MgSO4 and KPO4 No BME, but maybe some DTT. Purified from a proteobacterium. On 05/12/15 15:20, Dyda wrote: What is in buffer? Perhaps DTT and cacodylate? Fred  [32m******************************************************************************* Fred Dyda, Ph.D.                       Phone:301-402-4496 Laboratory of Molecular Biology        Fax: 301-496-0201 DHHS/NIH/NIDDK                         e-mail:fred.d...@nih.gov Bldg. 5. Room 303 Bethesda, MD 20892-0560      URGENT message e-mail: 2022476...@mms.att.net Google maps coords: 39.000597, -77.102102 http://www2.niddk.nih.gov/NIDDKLabs/IntramuralFaculty/DydaFred ******************************************************************************* [m -- ======================================================================= All Things Serve the Beam =======================================================================                                David J. Schuller                                modern man in a post-modern world                                MacCHESS, Cornell University                                schul...@cornell.edu