[RASMB] Weak association?

[Leech, AP]

Hello all,

I have done some SV runs at various concentrations 0.3-10 mg/ml on
a protein (~14 ka) and the sedimentation coefficient appears to
remain constant (about 1.58). I had expected it to drop slightly at
higher concentrations, and so I suspect a weak self association.
Buffer is NaCl/Tris.

Is it reasonable to try and estimate an association coefficient
from this sort of data, and what is the best way to do it? (Even
a lower limit would be acceptable, as the intent is to show that
dimerisation is not significant).

I'm working my way through Gilbert & Gilbert at the moment (Meth.
Enzymol vol 27, p273) but is there perhaps something more in the
"global analysis" line?

All comments appreciated,

Andrew

-- 
Dr Andrew Leech                   *  Laboratory Manager
Technology Facility               *  Molecular Interactions Laboratory
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