Solubilizing proteins

Mark Dixon (Mark.J.M.Dixon@charnwood.gb.astra.com)
Wed, 2 Oct 1996 17:34:31 +0200


We have a 12kDa cytoplasmic protein which is insoluble in
aqueous media at NMR concentrations, we would prefer a MINIMUM
of 1 mmol in 0.5 ml.

We thought about using a percentage of trifluoroethanol ( TFE
), but this appears to have a "side-effect" of instilling
alpha-helical structure in unstructured loops and bends. Our
protein is about 90% alpha-helical already in four bundles
connected by loops. Any more helicity and we will lose
tertiary structure and end up with a helical rod !! Not good.

SDS micelles and/or high temperature are not an option.

Can anyone suggest a method of solubilizing proteins up to NMR
concentrations without modifications to the tertiary
structure. We are amenable to additives, but obviously the
fewer the better.


If a large number of responses are posted to me, I will create
a summary for the list.


Thank you, Mark Dixon
Astra Charnwood

mark.j.m.dixon@charnwood.gb.astra.com