One small point: Just make sure that you are not too off from the contents of the protein solution. Sometimes protein solution may have a high amount of salt or things like that and we forget to include atleast half of this concentration into the cryo solution. This could easily crack the crystals depending on the concentration and the type of compounds in it.
Regards, Mathews -----Original Message----- From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of Leonard Thomas Sent: Wednesday, October 26, 2011 11:57 AM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] cryo protection A good number of things to try. Just a little more info that was asked for. The crystals are grown in Peg 3350 over a range of pH values using Bis-Tris Propane. The are coming out of 2 different salt conditions. My feeling is it is an osmolality problem though I also observed cracking when going into a separately made well solution. I will look it trying a number of suggestions given. Cheers, Len Leonard Thomas Ph.D. Macromolecular Crystallography Laboratory Manager University of Oklahoma Department of Chemistry and Biochemistry Stephenson Life Sciences Research Center 101 Stephenson Parkway Norman, OK 73019-5251 lmtho...@ou.edu http://barlywine.chem.ou.edu Office: (405)325-1126 Lab: (405)325-7571 On Oct 26, 2011, at 12:54 PM, Muhammed bashir Khan wrote: > Hi Len; > > I was having exactly the same problem with my crystals, but when we > grow > the crystals in presence of increasing concentration of Glycerol and > MPD > starting from 0.5 to 10%. The crystal doesn't appear after 3% of > Glycerol > or MPD but the one which appear in 2.5 to 3 % were much resistant to > cracking than the original crystals. > > Good luck > > Bashir > > On Wed, October 26, 2011 18:46, Leonard Thomas wrote: >> Hi All, >> >> I have run into a very sensitive crystals system when it comes to >> cryo >> protecting them. I have run through the usual suspects and trays are >> going to be setup with a cryo protectant as part of crystallization >> cocktail. The one problem that seems to be occurring is that the >> crystals crack as soon as they are transfered out of the original >> drop. I am running out of ideas and really would love some new ones. >> >> Thanks in advance. >> >> Len >> >> Leonard Thomas Ph.D. >> Macromolecular Crystallography Laboratory Manager >> University of Oklahoma >> Department of Chemistry and Biochemistry >> Stephenson Life Sciences Research Center >> 101 Stephenson Parkway >> Norman, OK 73019-5251 >> >> lmtho...@ou.edu >> http://barlywine.chem.ou.edu >> Office: (405)325-1126 >> Lab: (405)325-7571 >> > > > -- > Muhammad Bashir Khan > ************************************************** > Department for Structural and Computational Biology > Max F. Perutz Laboratories > University of Vienna > Campus Vienna Biocenter 5 > A-1030 Vienna > Austria > > Austria > > Phone: +43(1)427752224 > Fax: +43(1)42779522 > >
