Protein size in the SDSPAGE gel is different from the estimated size

[Michael Witty]

Dear Hicham,
           could you try blotting to PVDF and N-terminal sequencing?
Mike.

On 21 Jun 2001, Hicham Zegzouti wrote:

> Hi everybody,
>
> I am working on a protein whose estimated MW (from cDNA )is 120KD. I
> overexpressed this protein in E.coli and made an antibody against it.
> Until now normal!
> After purifying the Antibody using Affigel coupled to my protein and
> using this purified Ab aginst transferred plant protein extract, I
> obtain a signal just at around 90 KD. Does anybody have seen
> something like this and does anyone have an explanation for it. What
> do you think I can do to check that the band on the western
> corresponds to my protein?
>
> Thanks for your  help.
>
> Hicham
>
> ---
>