Hi Ruby, Did you try lowering your protein concentration? that might be the reason for precipitation...also try lowering the precipitant concentration...which crystallization method are you trying? If you are using microbatch method you can try hanging drop...and as Prof. Tim Gruene suggested, there is a large amount of literature and troubleshooting methods around..just search for it..and try out each possibilty systematically varying one or two parameters at a time..if you have some information regarding the structure you can analyze that to engineer your protein so that it crystallizes..
regards arko On Sat, May 5, 2012 at 12:23 PM, ruby singh <[email protected]> wrote: > > > On Sat, May 5, 2012 at 12:17 PM, ruby singh <[email protected]>wrote: > >> Sir, >> i m sorry for not giving full details of protein. >> its plant lectin protein on which im working currently. its sequence >> information is very little. crystallization has become near to impossible. >> the protein is a tetramer( of 28KDa). its purification is very >> simple...but for crystallization i tried many things nt working >> though(Hampton Reserach-pegion and index/CSS1/JCSG etc..). need some help. >> the protein conecentration used was 30mg/ml stock . most of the >> crystallization condition shows precipitation. the set up was put at 20C. >> the protein is very stable in MilliQ water upto 100mg/ml concentration with >> no precipitation. >> > the protein doesnt aggregate..doesnt loose activity even after boiling at > 80C. > > getting its crystal is important for my thesis. so need help. > > -- *ARKA CHAKRABORTY* *CAS in Crystallography and Biophysics* *University of Madras* *Chennai,India*
