Resolving LMW proteins

[pesusi at sara.cc.utu.fi]

In article <1994Mar28.180207.1 at pearl.tufts.edu>, ajayaram at pearl.tufts.edu writes:
> 
> Hi there,
> 
> I'm trying to run a 8 kd protein on a SDS get but I'm having some problems
> getting it to show up due to its small size.  I've tried 10, 12 and 15
> percent gels but the but the protein doesn't seem to be there ( the problem is
> obscured by the fact this protein is being made after an induction and the coli 
> proteins interfere with seeing the bottom of the lane where the 8 kd protein
> would presumably run.)  I've tried running the gels without loading dye in the
> sample buffer thinking that the dye front would obscure the 8 kD band.  This
> didn't help.  If anyone has any suggestions about resolving low molecular
> weight proteins please respond by posting in this group or emailing me
> directly.  Thanks.
   
   Hi!

I have few suggestions. Have you tried adding urea in your gels? It might help.
Also you could try gradient gels with or without urea (4-6 M might be good). I
have also tried changing pH in separating gel. It might help. It was said in
some article but unfortunately I could not find it. I suggest that you try pH
9,2 instead of 8,8 in your separating gel.
If you get good re3sults I would like to hear from it
 
Yours 

Peter
> 
> Arul
> ajayaram at pearl.tufts.edu
> 
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