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Re: [ccp4bb] weird thing about MR
 

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CCP4bb <-- 2007 <-- April 2007 <-- 27 April 2007
Previous message:
Subject: weird thing about MR
From: Yi Xue yi-xue {- at -} NORTHWESTERN {- dot -} EDU
Date: 2007-04-27 		Next message:
Subject: NCS-averaged composite omit map?
From: Paul Paukstelis paul {- at -} ICMB {- dot -} UTEXAS {- dot -} EDU
Date: 2007-04-27


Subject: Re: weird thing about MR
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2007-04-27
Such high R values usually mean there are many many very weak relections..
You havent kept in the h+k+l = 2n+1 reflections have you?
Do a native Patterson check too to make sure there are not other
translations which might distort the data

Eleanor

Yi Xue wrote:
> Dear all:
>
> I have a dataset diffracted to about 3A, and it is supposed to be
> protein/DNA complex. The spacegroup could be I4, I422, I222, or F222.
> I used the protein structure to start molecular replacement. There are
> three copies of complexes if assuming I422 symmetry. For the search of the
> first copy (phaser), the top solution had very good RFZ (7.4) and TFZ
> (18.1), meanwhile, there were total 44 good solutions, with RFZ>7 and
> TFZ>14. However, subsequent rigid body refinment of the top solution gave
> very high R and Rfree of around 80%. I tried all choices of space groups,
> briefly, they behaved similarly: MR found good solutions, R and Rfree were
> weirdly high.
>
> I was thinking maybe the spacegroup is wrong, I checked the data very
> carefully, and it seemed that the spacegroups I had chosen should be right.
> Any comments are highly appreciated.
>
>
> Best
> Yi
>
>
>

CCP4bb navigation

CCP4bb <-- 2007 <-- April 2007 <-- 27 April 2007
Previous message:
Subject: weird thing about MR
From: Yi Xue yi-xue {- at -} NORTHWESTERN {- dot -} EDU
Date: 2007-04-27 		Next message:
Subject: NCS-averaged composite omit map?
From: Paul Paukstelis paul {- at -} ICMB {- dot -} UTEXAS {- dot -} EDU
Date: 2007-04-27


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