blurry bands on SDS-PAGE

[Richard P. Grant]

In article 
<Pine.SGI.4.33.0203061519360.2867729-100000 at mole.bio.cam.ac.uk>,
 Michael Witty <mw132 at mole.bio.cam.ac.uk> wrote:

> . . . I think they are caused by residues with pKa's near the pH of the
> running buffer, like Histidine (pKa 6.0) and cysteine (pKa of
> thiol/thiolate (pKa about 9).  What do you think?  Regards, Mike.
> 
> (could it be a matter of solubility and caused by Phe and so on?).
> 

First I've heard of it.  Consider what the SDS is doing - it's swamping 
your protein's charge, so unless you've got something veeeeeeeeery 
strange . . .

-- 
Richard P. Grant  0x5F9559B1                         MRC Lab of Mol Biol
rpg 'at' mrc-lmb.cam.ac.uk           New:   http://www.rg-d.com/BioLOG/
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