Re: [ccp4bb] O/T: can a protein which dimerizes in solution crystallize as a monomer?

- Protein crystallography

Main steps:

- Protein purification
- Crystallisation

Special:

- Programs for crystallography
- X-ray detectors

Basic tutorials:

   - Chemistry
   - Protein
   - Peptide
   - Amino Acids

Xtal community:

- CCP4BB

CCP4bb navigation

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

Previous message:
Subject: Re: Offtopic: FAD enzymatic assay
From: conancao conan_cao {- at -} HOTMAIL {- dot -} COM
Date: 2008-12-01

Next message:
Subject: Re: O/T: can a protein which dimerizes in solution crystallize as a monomer?
From: "Brown, Kate A" k {- dot -} brown {- at -} IMPERIAL {- dot -} AC {- dot -} UK
Date: 2008-12-02

Subject: Re: O/T: can a protein which dimerizes in solution crystallize as a monomer?
From: "R {- dot -} J {- dot -} Lewis" r {- dot -} lewis {- at -} NCL {- dot -} AC {- dot -} UK
Date: 2008-12-02

hi thierry

we had a case where Spo0A in the phospho form was a dimer
in solution, and in the non-phospho form was a monomer. in the
crystal, we had monomers of the phospho form, and (domain-swapped)
dimers of the non-phospho form. turns out that the crystallisation
conditions affected the behaviour of the protein, converting a M->D
Kd from nanomolar to micromolar in the first instance, and the acid
pH of the crystallisation solution in the latter promoted domain-
swapping.

the biochemistry where we sorted all this out is:

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WK7-457CYHW-HN&_user=224739&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000014659&_version=1&_urlVersion=0&_userid=224739&md5=5d3b66d5d8d662753ec43bc94a173880

rick

Fischmann, Thierry wrote:
>
> Dear fellow crystallographers,
>
> This is a question which is not CCP4-related.
>
> Is anybody aware of a protein which is known to be a dimer in solution
> (say by SEC), and yet crystallizes as a monomer? Wouldn’t the high
> concentration in the crystallization drop further favor dimerization?
>
> In other words, if a protein crystallizes as a monomer, can I conclude
> that it does not form biologically relevant dimers in solution?
>
> Thank you in advance for your replies.
>
> Thierry
>
> *********************************************************************
> This message and any attachments are solely for the
> intended recipient. If you are not the intended recipient,
> disclosure, copying, use or distribution of the information
> included in this message is prohibited -- Please
> immediately and permanently delete.
>

--
R. J. Lewis
Professor of Structural Biology
Institute for Cell and Molecular Biosciences
Faculty of Medical Sciences Tel: +44 (0)191 222 5482
University of Newcastle Fax: +44 (0)191 222 7424
Newcastle upon Tyne, NE2 4HH, UK Email: R.Lewis@ncl.ac.uk

CCP4bb navigation

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

Previous message:
Subject: Re: Offtopic: FAD enzymatic assay
From: conancao conan_cao {- at -} HOTMAIL {- dot -} COM
Date: 2008-12-01