Re: [ccp4bb] low B factor for water

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

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Subject: Re: low B factor for water
From: Oliviero Carugo oliviero {- dot -} carugo {- at -} UNIVIE {- dot -} AC {- dot -} AT
Date: 2007-12-14

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From: Ian Tickle I {- dot -} Tickle {- at -} ASTEX-THERAPEUTICS {- dot -} COM
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Subject: Re: low B factor for water
From: "Murray, James W" j {- dot -} w {- dot -} murray {- at -} IMPERIAL {- dot -} AC {- dot -} UK
Date: 2007-12-14

Dear all,

> When I refined one of my structures in refmac and cns, I found some water
> molecules having low B factor (i.e < 10).

If no one else has suggested it calculate an anomalous difference map, these are very powerful, and can reveal very small f'' with good data.

James

Dr. James Murray
Biochemistry Building
Department of Biological Sciences
Imperial College London
London, SW7 2AZ
Tel: +44 (0)20 7594 5276

-----Original Message-----
From: CCP4 bulletin board on behalf of Oliviero Carugo
Sent: Fri 14/12/2007 07:25
To: CCP4BB@JISCMAIL.AC.UK
Subject: Re: [ccp4bb] low B factor for water

Dear Simon,

low B factors might indicate a higher number of electrons, i.e. an atom
larger than oxygen, like for example a metal cation (calcium etc.) of an
anion (chloride etc.). Take a look at the environment arounf the "strange"
solvent molecule.

Oliviero

On Thu, December 13, 2007 22:36, Yue Li wrote:
> Hi all,
>
> When I refined one of my structures in refmac and cns, I found some water
> molecules having low B factor (i.e < 10). Should I omit these water
> molecules from the structure ? The overall B factor is 35.3
>
> Thanks
>
> Simon
>
>

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

Previous message:
Subject: Re: low B factor for water
From: Oliviero Carugo oliviero {- dot -} carugo {- at -} UNIVIE {- dot -} AC {- dot -} AT
Date: 2007-12-14

Next message:
Subject: Re: CCP4 rotation convention
From: Ian Tickle I {- dot -} Tickle {- at -} ASTEX-THERAPEUTICS {- dot -} COM
Date: 2007-12-14