Hi Amit
My advise is similar to Artem's: A colleague of mine has very good
results in "immediate" streak seeding. He sets up drops covers them to
avoid evaporation during all the handling and then, he starts streak
seeding without delay.
christian
Artem Evdokimov wrote:
I would instead try for a **shorter** equilibration period, possibly
with just an hour or less. Or even try seeding into batch.
Artem
------------------------------------------------------------------------
*From:* CCP4 bulletin board [mailto:[EMAIL PROTECTED] *On Behalf Of
*amit sharma
*Sent:* Saturday, May 31, 2008 5:42 AM
*To:* [email protected]
*Subject:* [ccp4bb] streak seeding in the presence of Ammonium sulfate
Dear CCP4ers,
Apologies for a non-CCP4 question. I have been trying to streak seed one
of my protein crystals(clusters of needles) grown in the presence
of Ammonium sulphate. I set up the drops for equilibration overnight.
When I opened the coverslips to begin streak seeding (the next day),
within a few seconds the drops began to show precipitation. I must also
mention that the protein concentration in the drops was lowered to 2/3rd
of that in the original condition. Additionally, the conc. of ammonium
sulfate was dropped to about 75% of that present in the original
condition. Should I (a) lower the protein conc. further, (b) lower the
precipitant conc. more, (c) keep for a longer equilibration period, (d)
try a,b.c in tandem, (e) try sitting drops?
Many thanks in advance,
Amit
_______________________________________________________________________
Dr. Christian Biertümpfel
Laboratory of Molecular Biology
NIDDK/National Institutes of Health phone: +1 301 402 4647
9000 Rockville Pike, Bldg. 5, Rm. B1-03 fax: +1 301 496 0201
Bethesda, MD 20892-0580
USA
_______________________________________________________________________
