I find that odd because the first structure I ever worked on was a DNA
oligonucleotide grown in 0.2 M magnesium formate and it did not require
cryoprotection at all when flash cooled directly in the cryostream. I
learned from Ned Seeman's group a long while back that Mg2+ itself
worked reasonably well as a cryoprotectant at high concentrations. We
routinely freeze DNA crystals with 120 mM Mg formate and 10% MPD.
--paul
On 12/16/2013 04:36 PM, Xiao, Junyu wrote:
Dear all, sorry if this topic does not interest you. I wonder whether
anyone has experience with freezing crystals grown in ~0.2 M Magnesium
Formate. Garman and Mitchell suggested that "A major anomaly is
solution 44, 0.2 M magnesium formate, which requires 50% glycerol for
cryoprotection" in their 1996 paper (J Appl. Cryst. 29, 584-587).
Since 50% glycerol is kind of harsh, I wonder whether anyone has
tried alternative cryo protectant. Your kind help will be highly
appreciated.
Best regards,
Junyu
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Junyu Xiao, Ph.D.
University of California, San Diego
Leichtag Room 283
9500 Gilman Drive, 0721
La Jolla, CA 92093-0721
Lab phone: 858-822-0684
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