staining a chargeless protein

Wayne R. Baker baker at
Wed May 15 21:50:01 EST 1996

In bionet.molbio.proteins,  Olin Anderson  <oandersn at> wrote
:We are working with a 55 kDa polypeptide that has no charged amino acids.
:Attempts to stain the polypeptide on PAGE gels has failed - tries
:included commasie blue, amido black, silver, copper stain, Sypro, 
:anilionaphthalene sulfonate, and fluorescein isothiocyanate.  The only
:amino group is the N-terminal and it seems unreactive/blocked.  The
:only amino acids in the polypeptide are P, G, Q, Y, T, and S.  

  Not to be nosey, but a 55 kDa protein that has only 6 different amino
acids? Is this naturally occuring? 

:Any suggestions how to stain/detect this polypeptide in a gel?

  Coomassie interacts with basic groups, which won't do you much good.
Any chance you could use a gel reader in the 200 nm range? Your
background would probably be pretty high but it might work. You might
also browse through another discussion in this group on the effect of
proline content on mobility.

Wayne Baker (baker at  	He who has a why to live for
4288 Molecular Biology Building  	can bear almost any how.
Iowa State University            	--Nietzsche
Ames IA 50011    (515) 294 0781 

More information about the Proteins mailing list