Thanks for the protocole and advice! I'll put my spherulites on gel. It will make things clear.
Jan 2011/8/24 Regina Kettering <[email protected]> > Something to consider is the quality of the PEG 3350. We have found that > different qualities of PEG 3350 can give different results, depending on the > type and amount of contaminants. What used to be the Fluka PEG 3350 is now > the pharm grade of PEG 3350 (aka Miralax). We use high quality PEG 3350 for > normal screening, but switch to the highest quality grade we can get for > optimizing. > > Regina > > ------------------------------ > *From:* Jan van Agthoven <[email protected]> > *To:* [email protected] > *Sent:* Wednesday, August 24, 2011 2:05 PM > *Subject:* [ccp4bb] spherulites and PEG3350 > > Dear all, > > I recently obtained some spherulites while trying to crystallize my > protein. The spherulites are manually reproducible, but changing pH, protein > concentration, and salt concentration does not result in crystal formation. > Microseeding with crushed spherulites isn't a solution either as it only > yields new spherulites. Next stepp is the use of an optimization kit but I > have a limited amount of material, and I start doubting that these are > protein spherulites, as the spherulites are not particularly soft. The > condition contains 15% PEG 3350 and 200 mM NaCl. Does anyone know if PEG > 3350 forms easily spherulites around that concentration? > > > Thanks, > > >
