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Re: [ccp4bb] streak seeding in the presence of Ammonium sulfate
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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999
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From: Tim Gruene tg {- at -} SHELX {- dot -} UNI-AC {- dot -} GWDG {- dot -} DE
Date: 2008-05-31		Next message:
Subject: Crystallization focus on membrane proteins 2008 - Registration deadline JUNE 2nd
From: "Stojanoff, Vivian" stojanof {- at -} BNL {- dot -} GOV
Date: 2008-05-31


Subject: Re: streak seeding in the presence of Ammonium sulfate
From: Artem Evdokimov artem {- at -} XTALS {- dot -} ORG
Date: 2008-05-31

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:CCP4BB@JISCMAIL.AC.UK] On Behalf Of amit
sharma
Sent: Saturday, May 31, 2008 5:42 AM
To: CCP4BB@JISCMAIL.AC.UK
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


CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999
Previous message:
Subject: SUMMARY: stereo with Nvidia Quadro
From: Tim Gruene tg {- at -} SHELX {- dot -} UNI-AC {- dot -} GWDG {- dot -} DE
Date: 2008-05-31		Next message:
Subject: Crystallization focus on membrane proteins 2008 - Registration deadline JUNE 2nd
From: "Stojanoff, Vivian" stojanof {- at -} BNL {- dot -} GOV
Date: 2008-05-31
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