Re: [ccp4bb] Multiple nucleation

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Multiple nucleation
From: Jobichen Chacko jobichenc {- at -} NUS {- dot -} EDU {- dot -} SG
Date: 2007-03-29

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From: Jeremy Tame jtame {- at -} TSURUMI {- dot -} YOKOHAMA-CU {- dot -} AC {- dot -} JP
Date: 2007-03-30

Subject: Re: Multiple nucleation
From: Artem Evdokimov artem {- at -} XTALS {- dot -} ORG
Date: 2007-03-29

What often works for this scenario:

Change temperature. Try 21, 15, and 4C.

Add glycerol or ethylene glycol - set a screen with your condition as basis,
and % EG/glycerol across - from 1% to 15% in suitable increments

Find additives that produce no crystals, set up tray(s) with those, then
seed with your microcrystals (worked really well for me in a few cases)

Reduce protein concentration

Add gelling agents to the set-up

Regards,

Artem

_____

From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of
Jobichen Chacko
Sent: Thursday, March 29, 2007 7:45 PM
To: CCP4BB@JISCMAIL.AC.UK
Subject: [ccp4bb] Multiple nucleation

Hai All,

Sorry for the non Ccp4 question.

I got very small crystals for a protein and I am trying to optimize the
condition to improve the size of the crystal and reduce the number of
nucleation.

The crystals are coming from five to six conditions , all have PEG 3350 in
common.

Apart from PEG, the condition has Lithium sulphate and Bis Tris in one
condition and Ammonium suphate and HEPES in another condition, while the
third condition is Sodium malonate, Bis Tris and PEG. I am getting
thousands of small crystals with some precipitation.

I tried macroseeding and additive screen, but the crystals are not growing.

Any suggestions are more than welcome.

Thank you.

Jobi

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Multiple nucleation
From: Jobichen Chacko jobichenc {- at -} NUS {- dot -} EDU {- dot -} SG
Date: 2007-03-29

Next message:
Subject: Postdoc positions in Yokohama
From: Jeremy Tame jtame {- at -} TSURUMI {- dot -} YOKOHAMA-CU {- dot -} AC {- dot -} JP
Date: 2007-03-30