Thanks Artem and Frank (Was: Re: Ammonium Sulfate)

[Dima Klenchin]

"Dr. Artem Evdokimov" <eudokima at mail.ncifcrf.gov> wrote:

>1) Size exclusion
>3) Native gels at pH 6.5 and 8.5

These are the two I was thinking of but wasn't sure if they are 
sufficiently meaningful. Light-scattering - what exactly does it 
measure - size? or is it sensitive enough for conformation? 

>If you are masochistic, you can try NMR on your sample, 

No, thanks :-)

>Can you try refolding your protein around a substrate-mimic or inhibitor

Although this is third time I come accross such proteins, this time it 
is actually plain ole actin. That it is soluble after denaturation/dialysis is
well-known; that it does not polymerize after this is also well-known. 
I played with salts, Ca, Mg, ATP and the result is ~ same everywhere.
I was just thinking maybe it gets trapped into some conformation that
is "better" G-actin (in a sense that it is always soluble no matter what)
than a real G-actin. 

Kinda fascinating problem since this is the most abundant cellular 
protein in many species and the one for which, apparently, there are
special "custom-made" chaperons. The question is - why such a 
complexity for a simple idea of a reversible polymerizing agent? 

        - Dima