Dear all,
Sorry for this off-topic question.
I am studying a peripheral membrane protein (13kDa) by liquid state
NMR, which is stable at pH 9.0 (50mM CHES pH9.0, 150mM NaCl and 1mM
DTT). It crashes when I lower pH of buffer. The addition of 50mM Arg +
Glu works to stabilize the protein at low pH, but interfere with the
interaction between protein and phosphatidylinositol mono-phosphate
(PtdInsP1). I've already tried some other ways to stabilize the
protein, like high salt concentration (400mM), detergents (NP40 and
Triton X-100). None of them worked.
Any input would be very helpful.
All the best,
Ju
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