Re: [ccp4bb] Oxidation, again!

2009-11-16 Thread Frank von Delft
Hi Jeremiah -- the short answer is Yes You Must! Don't whether you need that high concentration generally, but if it's not too osmotically active, the crystals should be fine; test it. But when mounting SeMet crystals, it's always a good idea to add fresh DTT or TCEP or whatever, it seems to

[ccp4bb] Oxidation, again!

2009-11-12 Thread Jeremiah Farelli
Hello all, I posted here a few months ago. My post dealt with a protein crystal that was very sensitive to oxidation (with the SeMet derivative even more so). The protein grows in 24% PEG 1500, no more than 1 mM DTT, 0.05 M Hepes, pH 7.5, 1% glycerol. TCEP will not work, even at very low con