Dear All, I never tried it myself but could it be a sulphur SAD/MAD a possible alternative?
In my experience with heavy atoms (luckily just 2 proteins!) you may waste all of your crystals without finding any heavy metal bound! Or may be the first one you try works.... Ciao Stefano -----Original Message----- From: CCP4 bulletin board [mailto:ccp...@jiscmail.ac.uk] On Behalf Of Sebastiano Pasqualato Sent: Wednesday, 15 July, 2009 14:34 To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] heavy atom derivative choice Hi all, I've got crystals of a protein of ca 200 residues, with 2 free cysteines, 5 histidines, 2 methionines. We have nice diffraction for the native crystals, that grow in 150 mM KSCN, 17% PEG 3350, bis tris propane pH 8.8. We are crystallising the SeMet derivative, but I'm not completely sure I will be able to have nice crystals by saturday, when we have tunable time at the ESRF. I was thinking of trying with some heavy atom soaks, but only have like 30 crystals, so limited trials allowed! Which compound would you advice as more likely to work, and thus worth testing? Thanks in advance for the suggestions, ciao s -- Sebastiano Pasqualato, PhD IFOM-IEO Campus Dipartimento di Oncologia Sperimentale Istituto Europeo di Oncologia via Adamello, 16 20139 - Milano Italy tel +39 02 9437 5094
