Hi JK, As mentioned, phosphate salts are the main disadvantage - you can get round this by setting up two drops per well: one with your protein in PBS, and the other with PBS only. That way you should be able to quickly identify any hits that are due to salt, and which are likely to be your protein.
Tom On 15 November 2011 23:25, Jayakrishnan Nandakumar <sscna...@gmail.com> wrote: > Hi All, > I have an RNA-binding protein that I can purify out of bacteria in PBS > (Phosphate buffered saline;137 mM NaCl, 2.7 mM KCl, 10 mM Na2HPO4, 2 mM > KH2PO4), but which is insoluble in Tris/NaCl-based buffers. My guess would > be that the inorganic phosphates (by mimicking RNA) are binding the protein > to keep it in solution. My question is whether I can leave the protein in a > phosphate-based buffer (at lower salt maybe) to set up crystallization > trials or are PBS-based buffers not suitable for crystallization in general. > I have always used Tris/NaCl based buffers in the past. > > Thanks in advance for your suggestions. > Regards, > JK > -- Skype: tom.murray.rust Twitter: tmurrayrust http://twitpic.com/photos/tmurrayrust +44 7970 480 601 (UK)
