[ccp4bb] Highest shell standards

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

Previous message:
Subject: Easy proteins to crystallize -- summary
From: "Douglas L {- dot -} Theobald" dtheobald {- at -} BRANDEIS {- dot -} EDU
Date: 2007-03-21

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Subject: Re: Highest shell standards
From: Bart Hazes bart {- dot -} hazes {- at -} UALBERTA {- dot -} CA
Date: 2007-03-21

Subject: Highest shell standards
From: Shane Atwell satwell {- at -} SGXPHARMA {- dot -} COM
Date: 2007-03-21

Could someone point me to some standards for data quality, especially for publishing structures? I'm wondering in particular about highest shell completeness, multiplicity, sigma and Rmerge.

A co-worker pointed me to a '97 article by Kleywegt and Jones:

http://xray.bmc.uu.se/gerard/gmrp/gmrp.html

"To decide at which shell to cut off the resolution, we nowadays tend to use the following criteria for the highest shell: completeness > 80 %, multiplicity > 2, more than 60 % of the reflections with I > 3 sigma(I), and Rmerge < 40 %. In our opinion, it is better to have a good 1.8 Å structure, than a poor 1.637 Å structure."

Are these recommendations still valid with maximum likelihood methods? We tend to use more data, especially in terms of the Rmerge and sigma cuttoff.

Thanks in advance,

Shane Atwell

CCP4bb navigation

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

Previous message:
Subject: Easy proteins to crystallize -- summary
From: "Douglas L {- dot -} Theobald" dtheobald {- at -} BRANDEIS {- dot -} EDU
Date: 2007-03-21

Next message:
Subject: Re: Highest shell standards
From: Bart Hazes bart {- dot -} hazes {- at -} UALBERTA {- dot -} CA
Date: 2007-03-21