Re: [ccp4bb] CYS modification and choice of PEG

2017-05-18 Thread Jose Artur Brito
Dear Antonio, we have seen this type of modifications in some of our structures. The modification of the cysteine (to cysteine-sulfenic, sulfinic or sulfonic acid) usually arises from exposure to oxygen during crystallization. We managed to prevent this by either adding TCEP to the protein buffe

Re: [ccp4bb] CYS modification and choice of PEG

2017-05-17 Thread Keller, Jacob
t: Wednesday, May 17, 2017 4:04 PM To: CCP4BB@JISCMAIL.AC.UK<mailto:CCP4BB@JISCMAIL.AC.UK> Subject: [ccp4bb] CYS modification and choice of PEG I haven't asked anything for a loong time, so here are a couple of question "for the honourable members of the esteemed CCP4 bulleti

Re: [ccp4bb] CYS modification and choice of PEG

2017-05-17 Thread Keller, Jacob
AIL.AC.UK Subject: [ccp4bb] CYS modification and choice of PEG I haven't asked anything for a loong time, so here are a couple of question "for the honourable members of the esteemed CCP4 bulletin board" ... or as I'd usually say: "for y'all". ;) 1) I

Re: [ccp4bb] CYS modification and choice of PEG

2017-05-17 Thread Ethan A Merritt
On Wednesday, 17 May, 2017 20:03:42 Antonio Ariza wrote: > I haven't asked anything for a loong time, so here are a couple of > question "for the honourable members of the esteemed CCP4 bulletin board" ... > or as I'd usually say: "for y'all". ;) > > 1) I have this modified CYS in one of t