Re: [ccp4bb] Multiple nucleation

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

Previous message:
Subject: Re: Multiple nucleation
From: Mario Sanches msanches {- at -} LNLS {- dot -} BR
Date: 2007-03-30

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Subject: Re: Multiple nucleation
From: artem {- at -} XTALS {- dot -} ORG artem {- at -} XTALS {- dot -} ORG
Date: 2007-03-30

Subject: Re: Multiple nucleation
From: "Radisky, Evette S {- dot -} Ph {- dot -} D {- dot -} " Radisky {- dot -} Evette {- at -} MAYO {- dot -} EDU
Date: 2007-03-30

In addition to trying lower concentrations of PEG and protein, you might
consider whether aggregation in your protein stock or vibration in your
crystallization environment are contributing to the problem, and how
they might be minimized. It might be obvious, but we have found that it
is important for protein stocks to be filtered or centrifuged to remove
aggregates immediately prior to setting up drops, and if the protein
solutions have been sitting around for a few hours or a few days, they
must be centrifuged again. We also had a stupid incident recently where
conditions that had previously generated high quality crystals were
suddenly producing thousands of tiny crystals instead, and the problem
was traced to a clinical centrifuge that had been moved to an adjoining
bench and was vibrating the crystallization shelf.

Evette S. Radisky, Ph.D.
Assistant Professor and Associate Consultant II
Mayo Clinic Cancer Center
Griffin Cancer Research Building, Rm 310
4500 San Pablo Road
Jacksonville, FL 32224
(904) 953-6372 (office)
(904) 953-2857 (lab)

________________________________

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: Re: Multiple nucleation
From: Mario Sanches msanches {- at -} LNLS {- dot -} BR
Date: 2007-03-30

Next message:
Subject: Re: Multiple nucleation
From: artem {- at -} XTALS {- dot -} ORG artem {- at -} XTALS {- dot -} ORG
Date: 2007-03-30