you could try sitting drops. Perhaps you can fish a crystal quicker, before it degrades. In sitting drops the crystals may also be further away from the drop surface and take longer to degrade.
Or quickly add mineral oil to cover the sitting drop and fish the crystals through the oil.
If this is still too slow, you could try microbatch under oil and you should be able to fish the crystals without previous exposure to air.
You may need to adapt the mother liquor somewhat.
The mineral oil may not be compatible with your membrane protein and detergent, but without trying you will never know.
Mark J van Raaij
Laboratorio M-4
Dpto de Estructura de Macromoleculas
Centro Nacional de Biotecnologia - CSIC
c/Darwin 3, Campus Cantoblanco
E-28049 Madrid, Spain
tel. (+34) 91 585 4616
http://www.cnb.csic.es/content/research/macromolecular/mvraaij
On 24 May 2011, at 19:19, weikai wrote:
> Hi Folks,
>
> We have some membrane protein crystals that are grown in 30%PEG400, 0.1M Na Citrate pH 4.5, 0.1M LiCl. The protein is purified in DDM. The crystals are long rods and grown under room temperature in a hanging drop set up. But once we open the cover slip, we see the rods start to break and bend in a few seconds. Since it is in high PEG400, we just directly freeze the crystals. The diffraction only goes to 10 Ang at synchrotron. Have anybody had similar problem before and any suggestions?
>
> Thanks a lot,
>
> Weikai
>
>
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