Re: [ccp4bb] helix ordering upon metal binding

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

Previous message:
Subject: helix ordering upon metal binding
From: Florian Schmitzberger florian {- dot -} schmitzberger {- at -} KI {- dot -} SE
Date: 2008-04-08

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Subject: Re: helix ordering upon metal binding
From: Hector H Hernandez hectorh {- at -} MIT {- dot -} EDU
Date: 2008-04-08

Subject: Re: helix ordering upon metal binding
From: Patrick Loll pat {- dot -} loll {- at -} DREXEL {- dot -} EDU
Date: 2008-04-08

Here's an example (although not Fe):

Futterer, K., Ravelli, R. B. G., White, S. A., Nicoll, A. J. &
Allemann, R. K. (2008). Acta Cryst. D64, 264-272.

On 8 Apr 2008, at 9:02 AM, Florian Schmitzberger wrote:

> Dear All,
>
> Are there prominent examples of ordering of an alpha-helix within a
> protein upon metal binding (in particular Fe)?
>
> In my case, I observe that a 10 amino acid fragment seems to become
> visible in electron density maps, only upon Fe2+ binding to a
> glutamate (the first amino acid of the respective 10 residues). The
> fragment is part of a larger alpha-helix (which is ordered
> irrespective of metal binding). The 10 residue part (including the
> Glu) is not visible in the iron-free crystal structure in this
> subunit of the homodimer.
>
> I don't think that the helix is necessarily unfolding/folding,
> since in the other subunit in the asymmetric unit it is visible in
> the absence of Fe (probably due to crystal contacts). I am unsure
> about the significance, as it is only in one of the two subunits in
> the asym. unit that I see the ordering.
>
> Thank you very much in advance for any comments!
>
> Florian

------------------------------------------------------------------------
---------------
Patrick J. Loll, Ph. D.
Professor of Biochemistry & Molecular Biology
Director, Biochemistry Graduate Program
Drexel University College of Medicine
Room 10-102 New College Building
245 N. 15th St., Mailstop 497
Philadelphia, PA 19102-1192 USA

(215) 762-7706
pat.loll@drexelmed.edu

CCP4bb navigation

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

Previous message:
Subject: helix ordering upon metal binding
From: Florian Schmitzberger florian {- dot -} schmitzberger {- at -} KI {- dot -} SE
Date: 2008-04-08

Next message:
Subject: Re: helix ordering upon metal binding
From: Hector H Hernandez hectorh {- at -} MIT {- dot -} EDU
Date: 2008-04-08