W.M. B. wrote:
> Dear All:
>
> My protein/DNA complex crystal diffracts to 3.2 A ( in-house source).
> It crystalized in 20% PEG 8K, NaCaCo 6.5. I tried to add ATP, CaCl2
> and spermidine. The diffaction doesn't improve. Would you please give
> me some advice?
>
> Thanks a lot,
>
> Steve
>
>
>
>
How does your diffraction pattern look like ?
Is it smeary at the high res edges or do you have clear distinguishable
spots ?
Anisotropic diffraction ?
Diffraction clouds ?
Hint of ice rings ?
What size are the crystals ?
What is your inhouse source, how does it compare to synchrotron data
usually ?
I assume you have already played with different cryo-protectants
replacing PEG8K or keeping it in and adding smaller
PEGs/Glycerol/EG/Malonate/Olive oil/Paratone etc.
How about flash or wet annealing of the crystals, do they survive that
treatment ?
What holds you back to solve the structure at 3.2 A ? Just that arp/Warp
won't work ?
Juergen
--
Jürgen Bosch
University of Washington
Dept. of Biochemistry, K-426
1705 NE Pacific Street
Seattle, WA 98195
Box 357742
Phone: +1-206-616-4510
FAX: +1-206-685-7002
Web: http://faculty.washington.edu/jbosch
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