[ccp4bb] protein precipitated when they formed a complex

- Protein crystallography

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- Protein purification
- Crystallisation

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- Programs for crystallography
- X-ray detectors

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

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Subject: Re: insoluble ligand
From: Kendall Nettles knettles {- at -} SCRIPPS {- dot -} EDU
Date: 2007-12-12

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Date: 2007-12-12

Subject: protein precipitated when they formed a complex
From: Jerry McCully for-crystallizaiton {- at -} HOTMAIL {- dot -} COM
Date: 2007-12-12

Dear All,

Recently I posted a question about protein induced protein precipitation.
Firstly I'd like to thank many folks for their good ideas.

Later on I did a titration experiment with one protein concentration fixed at 0.4mg/ml(about 10uM). Now it is clear that these two proteins stoichiometrically precipitated when they formed a 1:1 complex. The excess of individual proteins was just soluble in the buffer.

How come these two proteins co-precipitated when they formed a complex?

Does anyone know some methods to keep the complex soluble enough for crystallization?

By the way, there is some additional information about the individual components. One has a pI of 6.5, and the other has a pI of 10.

Any suggestions will be highly appreciated.

Jerry McCully

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CCP4bb navigation

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

Previous message:
Subject: Re: insoluble ligand
From: Kendall Nettles knettles {- at -} SCRIPPS {- dot -} EDU
Date: 2007-12-12

Next message:
Subject: upgrading ccp4 broke my Coot stereo
From: Robert Grant ragrantmit {- at -} GMAIL {- dot -} COM
Date: 2007-12-12