[ccp4bb] Postdoc Position Available
Postdoctoral fellow, structural biology in DNA Damage Response, the University of Hong Kong, Hong Kong We currently have the opportunity to recruit a highly-motivated postdoctoral fellow to work on molecular mechanisms of intra-S-phase checkpoint activation in response to DNA damage. The candidate should have a strong background in macromolecular crystallography or protein NMR. A highly competitive salary commensurate with qualifications and experience will be offered. Annual leave and medical benefits will also be available. Interested candidates should email their CV, a summary of research experience/accomplishments, and arrange for 3 letters of reference to be sent directly to Dr. Chengmin Qian (cmq...@hku.hk).
[ccp4bb] Fwd: Re: [ccp4bb] Xtal formed during purification
-- Forwarded message -- From: "Roger Rowlett" Date: Aug 10, 2013 12:01 PM Subject: Re: [ccp4bb] Xtal formed during purification To: "ZHIZHI WANG" Cc: When I worked with S. typhimurium tryptophan synthase, it would crystallize directly from the crude lysate during ammonium sulfate precipitation. IIRC the history of this protein, these little crystals diffracted as well. In fact, 2x crystallization was how we purified the enzyme. Never saw a column. Sometimes you get lucky. Roger Rowlett On Aug 9, 2013 3:42 PM, "ZHIZHI WANG" wrote: > Hi all, >After I purified my target protein by ion exchange, I left the > fractions with high protein concentrations overnight @4C. Now I saw a lot > of small needle crystals inside the EP tubes this morning. > I wonder whether there is any technique or method to get bigger crystals > from this? > > ZZ >
Re: [ccp4bb] Xtal formed during purification
Dear Zhizhi, I worked with a postdoc a while ago who also got crystals when he concentrated his purified protein in the final step of purification. It might be worth testing whether your crystals are of diffraction quality or not. In my colleague's case, the rapidly growing crystals did not diffract at all but after he optimized his buffer conditions to prevent those non-diffracting crystals and screened for optimal crystallization conditions, he got hits from the screens that diffracted to 1.8 Ang. Cheers and good luck! Raji -- Raji Edayathumangalam Instructor in Neurology, Harvard Medical School Research Associate, Brigham and Women's Hospital Visiting Research Scholar, Brandeis University On Fri, Aug 9, 2013 at 4:20 PM, Tomas Malinauskas < tomas.malinaus...@gmail.com> wrote: > Dear Zhizhi, > we had a case like that. I would switch to slightly different buffer > (e.g. different pH) so crystals do not appear overnight, and then do > crystallisation screening. I bet you will have many hits in different > conditions, likely with bigger crystals. > Good luck! > Best wishes, > Tomas > > > > > On Fri, Aug 9, 2013 at 8:31 PM, ZHIZHI WANG > wrote: > > Hi all, > >After I purified my target protein by ion exchange, I left the > fractions with high protein concentrations overnight @4C. Now I saw a lot > of small needle crystals inside the EP tubes this morning. > > I wonder whether there is any technique or method to get bigger crystals > from this? > > > > ZZ >
