Hey :) Tubulin has high affinity towards colchicine. You may be able to subtract it via colchicine-agarose if you can get some, or have some of it made. Alternatively, merely adding colchicine may be enough to break the complex between tubulin and whatever it is you're purifying (is it a kinase -- kinases are actually often found as contaminants in tubulin preparations, and I bet the reverse can be true as well) http://www.ncbi.nlm.nih.gov/pubmed/3815600
There also are anti-tubilin antibodies that can be used if you're desperate enough. Notably, colchicine is fluorescent when bound to tubulin, but not by itself in aqueous solutions. Alternatively, I'd try phosphocellulose. You can also add GTP and Taxol in an attempt to stimulate microtubule formation - hopefully tubulin as actual tubules will release your protein of interest, or add excess GDP to try and destroy any polymeric material that might remain. Do you know which tubulin isoform you have the most (the gamma rings can be a pain to get rid of). Artem P.S. note that colchicine is not exactly a safe substancel it has nasty toxicity profile and should be treated with respect. On Thu, Jun 23, 2011 at 6:05 AM, Seungil Han <shan06...@gmail.com> wrote: > All, > I am sorry that this is off topic. > My target protein expressed in insect cell expression system is eluted with > tubulin contamination. We have tried ion exchange & sizing column to get > ride of tubulin from our target protein for structural studies. > > Has anyone had similar problem? Any suggestion? > > Thanks in advance. > Seungil > > > Seungil Han, Ph.D. > Pfizer Inc. > Eastern Point Road, MS8118W-228 > Groton, CT 06340 > Tel: 860-686-1788, Fax: 860-686-2095 > Email: > seungil....@pfizer.com<http://us.mc806.mail.yahoo.com/mc/compose?to=seungil....@pfizer.com>
