*** For details on how to be removed from this list visit the ***
*** CCP4 home page http://www.ccp4.ac.uk ***
Hi Sunando,
If you say you are mounting at room temperature I assume you are
mounting them in a capillary and not a cryo loop. I trust you do but
since capillary mounts are getting rarer I've seen many students that
don't know how to do it. If you mount in a capillary you'll want to
leave a little column of motherliquor in the capillary, some distance
away from the crystal to keep the humidity in the capillary high enough
to prevent the crystal from drying out. If none of the above helps then
you can try a wet mount. People have mounted crystals in a low
percentage of gelatine (if I remember well) or use some non-diffracting
fiber material as a plug to immobilize the crystal while surrounded by
mother liquor. Obviously your background scatter will go up but if your
good-size crystals diffract well then that should not be holding you back.
Bart
Sunando Datta wrote:
*** For details on how to be removed from this list visit the ***
*** CCP4 home page http://www.ccp4.ac.uk ***
Hi
this is not a crystallography question. I could able to grow reasonable
big(0.2-0.3mm) crystals of my protein. I am using 2-2.5% Peg4k/peg
5K(MME),Mg 5 mM, against 1M MgCl2 in reservoir(prot conc. approx. 20mg/ml, in hepes
,7.0,100mM NaCl, 1mMDTT, 10% glycerol). The crystals grow very fast(with in 1 day
they appear and grow to max. size by 4 days. They grow at room temp, not
at 4 deg.
The problem is wheneve they are exposed in air, I see lot of cracks on
the crystal surface..I am mounting at room temp. this problem is arising
for bigger crystals not for 0.1 mm crystals. Crystals are growing on a
skinny precipitate which is difficult to handle during mounting.
Have any one experienced this kind of situation? do the crystals diffract
with cracks on surface? if not how to tackle this problem??
Thanks
Sunando
--
==============================================================================
Bart Hazes (Assistant Professor)
Dept. of Medical Microbiology & Immunology
University of Alberta
1-15 Medical Sciences Building
Edmonton, Alberta
Canada, T6G 2H7
phone: 1-780-492-0042
fax: 1-780-492-7521
==============================================================================
