Re: [ccp4bb] Suggestions for Reducing Protein Precipitation

2010-08-13 Thread John Hinks
al Message- From: CCP4 bulletin board [mailto:ccp...@jiscmail.ac.uk] On Behalf Of David Briggs Sent: 12 August 2010 20:22 To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] Suggestions for Reducing Protein Precipitation Hi Matt, Have you tried changing the pH? Is it possible that at pH 8 you are

Re: [ccp4bb] Suggestions for Reducing Protein Precipitation

2010-08-12 Thread David Briggs
Hi all. I found that reference. :0) Acta Crystallogr D Biol Crystallogr. 2006 Jul;62(Pt 7):833-42. Epub 2006 Jun 20. Assessment of a preliminary solubility screen to improve crystallization trials: uncoupling crystal condition searches. Izaac A, Schall CA, Mueser TC. http://www.ncbi.nlm.nih.gov/

Re: [ccp4bb] Suggestions for Reducing Protein Precipitation

2010-08-12 Thread David Briggs
Hi Matt, Have you tried changing the pH? Is it possible that at pH 8 you are at the pI of your protein (i.e. where it has zero net charge and is at its least soluble) ? I have also read a paper (can't find the reference right now) where the authors precipitated their protein by dialysing into wat

Re: [ccp4bb] Suggestions for Reducing Protein Precipitation

2010-08-12 Thread Eric Toth
B@JISCMAIL.AC.UK Subject: [ccp4bb] Suggestions for Reducing Protein Precipitation Hi. I am working with a protein that has difficulties staying in solution when concentrated. The buffers that I have been using contain 20 mM Tris pH 8.0, 5 mM BME (or 2 mM DTT), 10% Glycerol, and NaCl from 50 mM

Re: [ccp4bb] Suggestions for Reducing Protein Precipitation

2010-08-12 Thread Das, Debanu
cp4bb] Suggestions for Reducing Protein Precipitation Hi. I am working with a protein that has difficulties staying in solution when concentrated. The buffers that I have been using contain 20 mM Tris pH 8.0, 5 mM BME (or 2 mM DTT), 10% Glycerol, and NaCl from 50 mM up to 2 M. The protein seems

[ccp4bb] Suggestions for Reducing Protein Precipitation

2010-08-12 Thread Matthew Bratkowski
Hi. I am working with a protein that has difficulties staying in solution when concentrated. The buffers that I have been using contain 20 mM Tris pH 8.0, 5 mM BME (or 2 mM DTT), 10% Glycerol, and NaCl from 50 mM up to 2 M. The protein seems fine to dialyze into low salt buffer (50 mM NaCl) when