Uncle S wrote:
> And as Arnoud van Vliet pointed out, it's quite common with His-tagged
> proteins to see significantly higher apparent MWs. I've got one that
> runs %50 higher than its calculated mass. As I told Tunyaplin via email,
> I wouldn't give up on the protein in question until taking a mass of it,
> which is easy and cheap.
>> > On Tue, 10 Mar 1998 ct133 at columbia.edu wrote:
> > > Does anybody know whether his-tagged protein expressed from pRSET
> > > vector (Invitrogen) can migrate aberrantly on SDS-PAGE?
> > > C. Tunyaplin
>> Shamus Young
I agree. I've used a different expression vector to express a His-tagged
migrated at ~55 KDa on SDS-PAGE but should actually be about 40 KDa strictly
according to calculated mass.
In my expreience, epitope tags can alter the migration of proteins on SDS-PAGE
dramatically (although I've never seen a protein migrate faster than expected
SDS-PAGE... how about anyone else?)
Darren Tyson, Ph.D. Candidate
Cell & Molecular Biology Program
Saint Louis University, St. Louis, MO
tysondr at nospam.slu.edu
(remove nospam. before mailing)