Hi Acoot, There are a lot of great suggestions here already. I've also run into this phenomenon in couple of cases. The first was a binding protein in mixed bound and unbound forms. The second was a case of heterogeneous post-translational modification. In both cases I could only get crystals from purified peaks and not pooled protein. If protein is precious I'd second Mark's suggestion to try screening pooled protein while you scale up your prep.
Cheers, Katherine On Sat, Dec 14, 2013 at 6:16 AM, Acoot Brett <[email protected]> wrote: > Dear All, > > When I purified my protein by ion exchange chromatography for > crystallization, there were several peaks containing the target protein as > analyzed by SDS-PAGE. All these peaks have the same MW as determined by gel > filtration coupled MALLS. > > For crystallization purpose, can I merge the corresponding ion exchange > chromatography peaks together? Otherwise the protein yield will be too low. > And how to explain the heterogeneity by ion exchange chromatography in this > situation? > > I am looking forward to getting a reply from you. > > Acoot > -- "Nil illegitimo carborundum"* - *Didactylos
