[ccp4bb] a refinement problem

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

Previous message:
Subject: Re: protein crystal decay problem
From: Juergen Bosch jbosch {- at -} U {- dot -} WASHINGTON {- dot -} EDU
Date: 2008-08-04

Next message:
Subject: POST DOC position available at MRC France (BM14 at the ESRF)
From: "Martin A {- dot -} Walsh" walsh {- at -} ESRF {- dot -} FR
Date: 2008-08-05

Subject: a refinement problem
From: Carl Soja allbette {- at -} GMAIL {- dot -} COM
Date: 2008-08-05

Dear all,

I have a refinement problem.
I used a perfect twinning structure(data set processed with P21212, supected
pseudo-symmetry and expanded the data to P2. twnning parameter used the
refinement)
as a search model to do MR. After MR I can get a Rfac 0.52 structure. I am
refining the structureat 2.8A using CNS, however, after many refinement
cycles, Rfree is still over 40% . Actually, they are the same protein.
the search model is a RNA-protein complex structure, and my
structure(spacegroup C2221 )is a apo structure.
I can see a good density in my structure.

I don't know whether the high Rfree is model bias from twinning structure
or not?
How to do the high Rfree refinement?

Any advice and suggestion are welcome.

Thank you very much in advance.

Best

Jun

CCP4bb navigation

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

Previous message:
Subject: Re: protein crystal decay problem
From: Juergen Bosch jbosch {- at -} U {- dot -} WASHINGTON {- dot -} EDU
Date: 2008-08-04

Next message:
Subject: POST DOC position available at MRC France (BM14 at the ESRF)
From: "Martin A {- dot -} Walsh" walsh {- at -} ESRF {- dot -} FR
Date: 2008-08-05