Hi all, I was wondering if anyone has had any experience with setting up Fab:peptide complexes for crystallization. I have Fab protein and peptide and I am not sure how to add the peptide to the Fab protein. My peptide is hydrophobic and thus not very soluble in standard aqueous buffers and barely soluble in some organics. The Fab protein I have is currently in 100mM Sodium Acetate pH5, 150mM NaCl. My current plan is to dissolve lyophilized peptide first in 10% DMSO and use this stock to add to Fab protein in a 20:1 or 10:1 molar ratio. I am not sure of the effects of residual DMSO on peptide binding to Fab or on crystallization. I have read one paper in which they rave about DMSO as an additive in their crystallization, but that protein was not Fab like at all. Any insight you all might have on this would be greatly appreciated.
Thanks in advance, Christine
