RE: [ccp4bb]: cryo conditions

[Artem Evdokimov]

Hi,   Over the years I’ve developed a fairly robust freezing scheme which may work for you. It involves adding three components to the mother liquor (native or synthetic): ethylene glycol, NDSB-201, and sucrose. Sucrose is used primarily to match the density/osmolarity of the cryo-solution to that of the crystal, whereas the other two components are orthogonal cryoprotectants.   We’ve had cases where only one of the three was sufficient, but also cases where exact concentrations of all three were needed to save the crystals. If you want further details please feel free to email me and I’d be happy to provide more information.   Artem ex-PGP   From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Vincenzo Carbone Sent: Sunday, April 09, 2006 10:28 AM To: ccp4bb@dl.ac.uk Subject: [ccp4bb]: cryo conditions   Hi guys   Sorry for the non ccp4 based question but i was wondering if anyone has any tips on producing a suitable cryo buffer for crystals grown in peg8000. My crystals come out quite quickly in 15 to 10% peg and can be quite large. Ive tried to increase the peg concentration, replacing  the peg with glycerol or using a combination of peg8000 and glycerol but each time the crystals fail to diffract when flash frozen. Previous experience with these crystals have shown diffraction of up to 2A when dry mounted.   thanks,     vince