Min,
In some of my Xtal conditions, I only have 1.5 to 2M AmSO4 without KCl, the
salt comes out of solution only after maybe several minutes which is enough to
harvest the crystal. Maybe you could just direct freeze to try the diffraction
since it is already at high salt concentration or maybe add some mother liquor
to prevent it the salting out. I also suggest Mitegen LV cryo oil which works
for many cases for me.
Best,Hongnan Cao, Ph.D.Department of BiochemistryGreat Lakes Bioenergy Research
CenterUniversity of Wisconsin, Madison
Date: Tue, 10 Jul 2012 12:28:30 -0400
From: mzhang...@hotmail.com
Subject: [ccp4bb] cryo for high salt crystal
To: CCP4BB@JISCMAIL.AC.UK
regaentDear All,
I am sure this question was discussed before. But I am wondering if anyone got
the same experience as I do. I got a crystal out of condition with 1M KCl, 1.4M
Ammonium sulfate at pH7. I tried to use glycerol, ethylene glycol, 25% sucrose,
paraton-N oil, or ammonium sulfate itself: The problem is that all the cryo
plus original reagents in the reservoir precipitate the salts out. And more
serious problem is because of high salt in the condition, while I am trying to
loop the crystal, both the drop and cryoprotectant drop form salt crystals (not
sure it is KCl or ammonia sulfate) significantly and very quickly, that cause
my crystal dissolved. My crystal doesn't seem to survive paraton-N oil. Does
anyone here have similiar case? any suggestion will be appreciated.
Thanks,Min
