Disappearance of crystals is fairly common and not specific to DDM or indeed any detergent as it also occurs for soluble proteins. Even after reaching "equilibrium" conditions still change (evaporation, instability of components, proteolysis, etc). The inverse also happens, that is formation of regular crystals from irregular, "blobby' ones.
I assume you tested the crystals before they disappear? If you hope they get better upon prolonged incubation: I don't think there is much you can do to prevent their disappearance.
Bert
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From: CCP4 bulletin board [[log in to unmask]] on behalf of Yibin Lin [[log in to unmask]]
Sent: Saturday, June 15, 2013 8:48 PM
To: [log in to unmask]
Subject: [ccp4bb] crystals disappear
Hi forks,
I got some membrane protein crystals in DDM. However, after one month,
these crystals change to Irregular shape, and have not birefringent in
polarized Light. Do anybody know why? Does the effect of DDM? Contain
too much detergent?
Thanks,
Zhang Peng
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