Hi Frank, In our hands, some RNAs only crystallize out of cacodylate buffers. We would otherwise stop using it out of health and safety concerns.
Blaine Blaine Mooers Assistant Professor Department of Biochemistry and Molecular Biology University of Oklahoma Health Sciences Center S.L. Young Biomedical Research Center Rm. 466 Letter address: Shipping address: P.O. Box 26901, BRC 466 975 NE 10th Street, BRC 466 Oklahoma City, OK 73190 Oklahoma City, OK 73104-5419 office: (405) 271-8300 lab: (405) 271-8313 fax: (405) 271-3910 e-mail: blaine-moo...@ouhsc.edu webpage: http://www.oumedicine.com/department-of-biochemistry-and-molecular-biology/faculty/blaine-mooers-ph-d- ________________________________________ From: CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] On Behalf Of Frank von Delft [frank.vonde...@sgc.ox.ac.uk] Sent: Friday, November 09, 2012 6:26 AM To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] usefulness of cacodylate? Hi all - Anybody know a) how hazardous is cacodylate? b) does it really matter for crystallization screens? It seems by far the most hazardous component of the standard screens; this 2011 paper seems to think so (bizarrely, I can't access it from Oxford): http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2818.1977.tb01136.x/abstract and this is site says lethal dose is 0.5-5g/kg: http://cameochemicals.noaa.gov/chemical/4468 meaning 2ml of a 0.1M solution contains 1/10th lethal dose...? (Someone should check my maths...) [Coarse screens come mixed 2ml per condition.] Has anybody done careful experiments that showed it really mattered for a given crystal -- or even an entire screen? So I'm inclined to toss it out entirely rather than make crystallization screening a "hazardous activity". (We're being subjected to a safety review.) Thoughts welcome. phx
