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Re: Freezing

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On Thu, 23 Sep 1999, Lisa Edberg wrote:

> Glycerol,
> ethylene glycol , etc.  tend to solubilize protein; often even higher
> concentrations of precipitant are needed to avoid redissolving.

which brings me to my suggestion. if the glycerol is causing the crystal
to dissolve, try adding more precipitant along with the glycerol. for my
current heme oxygenase structure, the crystal conditions included over 2 M
ammonium sulfate. the glycerol cryo-protectant increased protein
solubility, so i added even more ammonium sulfate. seems a bit
counter-intuitive, but:
"It worked for me"

     Crystals are pretty, but they just kind of sit there,
         not doing much of anything.  - Larry Wall
                        David J. Schuller
                        modern man in a post-modern world
                        University of California-Irvine