Re: [ccp4bb] Unusual Difference Fourier near Methionines

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

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Subject: Re: Unusual Difference Fourier near Methionines
From: artem {- at -} XTALS {- dot -} ORG artem {- at -} XTALS {- dot -} ORG
Date: 2007-04-13

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From: Martyn Symmons martainn {- at -} OSHIOMAINS {- dot -} FREESERVE {- dot -} CO {- dot -} UK
Date: 2007-04-13

Subject: Re: Unusual Difference Fourier near Methionines
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2007-04-13

I think the SD-CE is pointing the wrong way. And they look much too close.
I would rotate them and re-refine
Eleanor

PS - any noise on the 3 fold axis will be multiplied by a factor of 3

Ethayathulla Abdulsamath wrote:
>
>
> Dear all
>
> I am doing one structure at 2.6A resolution where I found unusual
> density near methionines. Actually three methionines come close
> together nearby and I get difference even at 5sigma cutoff. I don't
> understand nature of the density. The amino acid sequnce is same I
> mean met by chemical sequncing so there is no change amino acid
> residues. I am sending the snapshot of the difference fourier observed
> at methionines. The crystal belong to R32 system with one molecule and
> biological trimer. In snapshot two of the methionines are symmetry
> related.
>
> Details of the data collection.
> Data collected at synchrotron
>
> Overall Rsym = 6 % and I/sigma = 2.1. Completeness = 99%
>
> Can anyone suggestion what could be chemical nature for the difference
> fourier.
>
> Thanks in advance
>
> Ethayathulla
>
> ###################################################
> A.S.Ethayathulla,Ph.D.
> Department of Biophysics
> All India Institute of Medical Sciences
> Ansari Nagar
> New Delhi-110029
> India.
> ###################################################
>
>
> Imagine
>
>
>

CCP4bb navigation

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

Previous message:
Subject: Re: Unusual Difference Fourier near Methionines
From: artem {- at -} XTALS {- dot -} ORG artem {- at -} XTALS {- dot -} ORG
Date: 2007-04-13

Next message:
Subject: Re: oxidised cys
From: Martyn Symmons martainn {- at -} OSHIOMAINS {- dot -} FREESERVE {- dot -} CO {- dot -} UK
Date: 2007-04-13