4M NaCl should work too. It worked for the conditions with 1.8 - 2.0 M NaCl.
Karolina W dniu 2014-02-19 06:38, Mooers, Blaine H.M. (HSC) napisał(a): > For crystals grown out of a 2 uL drop of 1.2-1.8 M LiSO4 or 1.6-2.4 M AmmSO4, > we do in situ cryoprotection with sodium malonate. We add 2-4 uL of 1.9 M Na > malonate to the crystallization drop, wait 10 seconds and add 2-4 uL of 2.4 M > sodium malonate, repeat with 2.8 M and then 3.4 M. We do not bother > withdrawing aliquots to maintain a fixed volume. You may need to tweak the > volumes to optimize the resulting diffraction. You can also break the > additions at given concentration into smaller aliquots to reduce the osmotic > shock. This approach is much gentler than transferring the crystal directly > to 3 M sodium malonate. Do not leave the drop exposed to the air for more > than 3 minutes or so because salt crystals will start to grow. When there are > multiple crystals in a drop, often the unused crystals in the very high salt > solution will still diffract well up to a year later if the crystallization > chamber is resealed well; their diffraction might even improve with the > prolonged exposure to high salt. > > Blaine Mooers > Assistant Professor > Department of Biochemistry and Molecular Biology > University of Oklahoma Health Sciences Center > S.L. Young Biomedical Research Center Rm. 466 > > Shipping address: > 975 NE 10th Street, BRC 466 > Oklahoma City, OK 73104-5419 > > Letter address: > P.O. Box 26901, BRC 466 > Oklahoma City, OK 73190 > > office: (405) 271-8300 lab: (405) 271-8313 fax: (405) 271-3910 > e-mail: blaine-moo...@ouhsc.edu > > Faculty webpage: > http://www.oumedicine.com/department-of-biochemistry-and-molecular-biology/faculty/blaine-mooers-ph-d- > [1] > > X-ray lab webpage: > http://www.oumedicine.com/department-of-biochemistry-and-molecular-biology/department-facilities/macromolecular-crystallography-laboratory > [2] > > Small Angle Scattering webpage: > http://www.oumedicine.com/docs/default-source/ad-biochemistry-workfiles/small-angle-scattering-links.html?sfvrsn=0 > [3] > ________________________________________ > From: CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] On Behalf Of Katherine > Sippel [katherine.sip...@gmail.com] > Sent: Tuesday, February 18, 2014 12:08 PM > To: CCP4BB@JISCMAIL.AC.UK > Subject: [ccp4bb] High Salt Cryo > > Hi all, > > I'm looking for a cryo condition for high NaCl (3+ M) crystallization > condition. I would do it the proper way, but our beam/cryostream is down. > > I've tried a bunch of things at the moment. Ethylene glycol and PEG 400 nuke > the crystals immediately even at low concentrations. Prolonged exposure to > glycerol and sucrose starts to break them down so I'm thinking that the > diffraction will probably suffer. I can't find any reports of NaCl's > viability as a cryosalt. I've got Paratone/Paraffin oil/Mitegen's LV cryo oil > on tap but I was hoping to not put all my eggs in one basket. > > I tried the ISRDB database through > archive.com<https://urldefense.proofpoint.com/v1/url?u=http://archive.com&k=7DHVT22D9IhC0F3WohFMBA%3D%3D%0A&r=ftLbjJYpc5s5JQz9Q6qd7uT7FxPLb4V0aIwH4RJhyZU%3D%0A&m=Vjr4m%2Fds%2FdLGOVQoQ0x8PApF%2FzyGkSwsbIoq92CSnOk%3D%0A&s=3cfbf18821b5b59934971bf583cf3dd6e2ded91923c614e670857e10916c687e > [4]> without any luck (no search function). I've gone to the PDB searching > for similar crystallization conditions and looked up the papers for their > cryos, but they are all glycerol. Google gives me the same. > > I thought I'd see if anyone on the bb has an anecdotal "this worked for us" > story. I would love to hear it. > > Thank you for your time, > Katherine > > -- > "Nil illegitimo carborundum" - Didactylos Links: ------ [1] http://www.oumedicine.com/department-of-biochemistry-and-molecular-biology/faculty/blaine-mooers-ph-d- [2] http://www.oumedicine.com/department-of-biochemistry-and-molecular-biology/department-facilities/macromolecular-crystallography-laboratory [3] http://www.oumedicine.com/docs/default-source/ad-biochemistry-workfiles/small-angle-scattering-links.html?sfvrsn=0 [4] https://urldefense.proofpoint.com/v1/url?u=http://archive.com&k=7DHVT22D9IhC0F3WohFMBA%3D%3D%0A&r=ftLbjJYpc5s5JQz9Q6qd7uT7FxPLb4V0aIwH4RJhyZU%3D%0A&m=Vjr4m%2Fds%2FdLGOVQoQ0x8PApF%2FzyGkSwsbIoq92CSnOk%3D%0A&s=3cfbf18821b5b59934971bf583cf3dd6e2ded91923c614e670857e10916c687e
