Re: [ccp4bb] Protein-DNA complex prepartion for crystallization

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

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Subject: SOme wquestions about refining.......
From: AA awaan686 {- at -} STUDENT {- dot -} OTAGO {- dot -} AC {- dot -} NZ
Date: 2008-10-01

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Subject: Re: Protein-DNA complex prepartion for crystallization
From: devendra srivastava dbcrystal {- at -} GMAIL {- dot -} COM
Date: 2008-10-01

Hi Raj,

I would definitely 10 mM MgCl2. I would also increases NaCl conc. as 200-250
mM.
Also you can try 5 mM DTT.

Good Luck

Dev

Devendra B. Srivastava
Postdoctoral Associate
Laboratory of Molecular Biophysics,
The Rockefeller University
1230 York Avenue
New York, NY-10021, USA
Phone: 212-327-7478 (Lab)
339-222-7670 (Mobile)

On Wed, Oct 1, 2008 at 6:52 PM, E rajakumar wrote:

> Dear All
> Sorry for non-crystallography query. I am working on
> DNA binding protein, while mixing DNA with protein for
> preparing Protein-DNA complex for crystallization,
> protein is precipitating. pI of the protein is 9.3
> and in 15 mM HEPES 7.0, 150mM NaCl and 5% glycerol.
> Concentration of the protein used for mixing with DNA
> is 8 mg/mL. DNA to protein molar ratio is 1.2. Please
> advise me how to prevent precipitation. Is changing of
> buffer pH and adding divalent cation like MgCl2 can
> help in preventing precipitation?
> Thanking You
> Rajakumara
>
>
> E. Rajakumara
> Postdoctoral Fellow
> Strcutural Biology Program
> Memorial Sloan-Kettering Cancer Center
> New York-10021
> NY
> 001 212 639 7986 (Lab)
> 001 917 674 6266 (Mobile)
>
>
>
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CCP4bb navigation

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

Previous message:
Subject: SOme wquestions about refining.......
From: AA awaan686 {- at -} STUDENT {- dot -} OTAGO {- dot -} AC {- dot -} NZ
Date: 2008-10-01

Next message:
Subject: Re: SOme wquestions about refining.......
From: Juergen Bosch jbosch {- at -} U {- dot -} WASHINGTON {- dot -} EDU
Date: 2008-10-02