James Bassuk wrote:
> nonsense. his-tag won't by itself cause nothing more than an increase
> in MW of 600.
Well, the question referred to the pRSET vector. check it out at
http://www.invitrogen.com/cat_xpress.html
The tag there comes with all the bells and whistles, EK cleavage,
antibody epitope, to the tune of ~30 residues, not 6.
> but, being a recombinant protein, all kinds of screwy things can happen.
> your question is too general because every protein would have an
> emperical answer.
Actually, their question is neither nonsense or too general. They were
just asking if it was possible, which it certainly is. I don't mean in
the overly literal cop-out sense that every protein can run abberantly.
I took the question to simply be asking for others' experiences with
his-tagged systems.
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
Dept. of Biochemistry
Box 357742
Universtiy of Washington
Seattle 98195-7742
--
The difference between love and hate is: hate lasts.
-Bukowski
