Dear Catrine can you comment on the pH range of your crystallization hits compared to the pH of the sample you use for your crystallization trials? The pH can be a major issue depending on the nature of the interaction interface.
best regards Savvas On 14 Mar 2011, at 13:21, Catrine Berthold Siöberg wrote: > Dear CCP4bb, > I am trying to solve the structure of a protein-protein complex. The two > proteins are co-expressed and co-purified and I get a homogeneous 1:3 > complex, which is the predicted composition. I get several hits using > commercial crystallisation screens (including the MD ProPlex screen), but all > crystals only contain the trimeric, more stable protein of the two. > > I am now considering to crosslink them, but my problem is that I cannot > modify them separately to get a specific crosslink, since one of the proteins > precipitates by itself. > I would appreciate all protocols for crosslinking of proteins aimed for > crystallisation, or references to structures solved of crosslinked proteins. > > Thank You, > Catrine > > -- > Catrine Berthold Siöberg, PhD > Stockholm Center for Biomembrane Research > Department of Biochemistry and Biophysics > Stockholm University > S-106 91 Stockholm > Sweden > e-mail: catrine.siob...@dbb.su.se > phone: +468-162451