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

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

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

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Subject: Re: Protein-DNA complex prepartion for crystallization
From: Antony Oliver antony {- dot -} oliver {- at -} ICR {- dot -} AC {- dot -} UK
Date: 2008-10-02

Dilute both the Protein and DNA before mixing them at the molar ratio
you require - I would aim to have the protein component at around 1 mg/ml.
Mix, then concentrate together, till you reach the concentration you want.

Antony.

> 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
>

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CCP4bb navigation

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

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

Next message:
Subject: Re: R32 data
From: Peter Zwart PHZwart {- at -} LBL {- dot -} GOV
Date: 2008-10-02