Re: [ccp4bb] PEG interaction with Trp in active site

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

Previous message:
Subject: Re: domain contact surface
From: Pierre Rizkallah rizkallahp {- at -} CARDIFF {- dot -} AC {- dot -} UK
Date: 2010-02-19

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Subject: Re: [ccp4] domain contact surface
From: Matthias Haffke matze_haffke {- at -} HOTMAIL {- dot -} COM
Date: 2010-02-19

Subject: Re: PEG interaction with Trp in active site
From: xaravich ivan xaravich {- dot -} ivan {- at -} GMAIL {- dot -} COM
Date: 2010-02-19

Is this the active enzyme or an inactive mutant? does your substrate have
any similarity with PEG (size, conformation, bulk etc?) would you assume
that if there was a substrate bound to the active site and say a few waters,
and/or metal ions it would probably fill the space which in this case PEG is
taking.

I think it would be more work, but the best way would be to try to
crystallize a inactive mutant with very less change in the active site
residues with the substrate( or active enzyme with an analog) and see if the
PEG is displaced.

ivan

On Fri, Feb 19, 2010 at 3:42 AM, Marek Frischerkase <
frischerkasemarek@yahoo.de> wrote:

> Hello,
> sorry for my off topic question.
> I found a PEG molecule bound to the active site of my enzyme structure. And
> I did not expected it there, though I used PEG as precipitant in the
> crystallization condition. Now I'm wondering how could bind PEG with its
> hydrophobic nature at all in the hydrophobic active site? It seems that the
> PEG molecule interacts predominantly with Tryptophans (distance 3.8 A). Did
> anybody observe similar cases? And which kind of interaction should there be
> active? I would be grateful for your help,
>
> cheers,
>
> Marek
>
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CCP4bb navigation

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

Previous message:
Subject: Re: domain contact surface
From: Pierre Rizkallah rizkallahp {- at -} CARDIFF {- dot -} AC {- dot -} UK
Date: 2010-02-19

Next message:
Subject: Re: [ccp4] domain contact surface
From: Matthias Haffke matze_haffke {- at -} HOTMAIL {- dot -} COM
Date: 2010-02-19