From: Gunther.Kern@astrazeneca.com
  To  : rasmb@bbri.org
  Date: Fri, 15 Oct 1999 17:23:44 +0200

sedimentation equilibrium runs at high salt concentrations

Has anyone done equilibrium sedimentation experiments at 3.2 M KCl and knows
how to correct for the effects of those conditions on diffusion?
I am looking at a protein that is dimer under normal conditions with a
dimeric MW of 60KDa. At 3.2 M salt I do get a MW of 41KDa after correcting
for the increase in solvent density (1.158g/ml). The curve fits perfectly to
a single species. However I have not done any other corrections and the
distribution curve should be different due to a decreased diffusion at high
salt concentrations. 
Any comments on how to correct for this are welcome.
Thank you very much,

Gunther Kern