anomalous protein migration SDS-PAGE

Jonathan B. Marder MARDER at
Fri Jan 27 06:29:06 EST 1995

lenny at (Lenny Garfinkel) wrote:
>This group appears to be dead, but I guess I can't lose by posting.  I
>have a fermentation supernatant (does not matter what organism) which I
>suspect contains proteases.  When I add a pure protein to the sup and
>incubate for anywhere from 0.5 hr to overnight, I see an apparent
>INCREASE in molecular weight on SDS-PAGE in the presence of
>mercaptoethanol (yup, it runs slower).  What sort of protein
>modifications could cause this?  Could clipping of a few residues result
>in less SDS binding?
Yes, especially if you chop off a bit of positively charged sequence

Jonathan B. Marder                 '
Department of Agricultural Botany  |     Internet: MARDER at
The Hebrew University of Jerusalem | /\/
Faculty of Agriculture             |/  \ Phone:    (08 or +9728) 481918
P.O.Box 12, Rehovot 76100, ISRAEL  /     Fax:      (08 or +9728) 467763

More information about the Proteins mailing list