Hi Subbu,
You got crystals at 1mg/ml so you probably don't need to concentrate your
protein any higher, especially since you suggest that concentrating beyond that
is problematic. Instead, you may want to try to optimize the crystallization
condition you have already identified. Some possible things to try: additive
screen, include specific ligands, different temperature, different ratios of
protein solution to crystallization solution, seeding, different
crystallization methods (hanging vs. sitting drop, batch, diffusion,...), ...
good luck,
Eric
================================
Eric T. Larson, PhD
Biomolecular Structure Center
Department of Biochemistry
Box 357742
University of Washington
Seattle, WA 98195
email: larso...@u.washington.edu
================================
On Thu, 21 Jul 2011, Narayanan Ramasubbu wrote:
Dear All:
We have been trying to crystallize a protein which is large - > 100 kDa. This
is soluble but the best we can get is about 1 mg/mL.
It did crystallize but did not diffract well. Efforts to increase the
concentration has been unsuccessful. I am wondering whether there are methods
that others use to increase the concentration other that using amicon columns.
Any help will be appreciated.
Thanks
Subbu
