Re: [ccp4bb] how to bring back the missing density for half of the structure

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CCP4bb <-- 2007 <-- August 2007 <-- 01 August 2007

Previous message:
Subject: Re: difference density ripples around Hg atoms
From: Bart Hazes bart {- dot -} hazes {- at -} UALBERTA {- dot -} CA
Date: 2007-08-01

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Subject: Re: difference density ripples around Hg atoms
From: "George M {- dot -} Sheldrick" gsheldr {- at -} SHELX {- dot -} UNI-AC {- dot -} GWDG {- dot -} DE
Date: 2007-08-01

Subject: Re: how to bring back the missing density for half of the structure
From: Peter Adrian Meyer pam52 {- at -} CORNELL {- dot -} EDU
Date: 2007-08-01

> If your Phaser results show a high Z-score (> 8) AND high LLG AND your
> solution packs without clashes AND refines (even though starting R/Rfree
> is high) AND reproduces density for the model portion AND produces some
> Fo-Fc density for the missing portion, most probably your solution is
> correct.

AND the z-score for your solution stands out from the z-scores for
incorrect (/other) solutions. I've gotten z-scores > 8 for a known
incorrect solution while testing (searching for a domain not present in
the crystal, so this test was probably unrealisticly difficult). The
highest/second highest z-scores for the incorrect domain were roughtly
equal (~8.7/~8.2); for the correct domain they were ~ 35/7).

So as long as you're checking phaser statistics, this is another one to
check.

Pete

Pete Meyer
Fu Lab
BMCB grad student
Cornell University

CCP4bb navigation

CCP4bb <-- 2007 <-- August 2007 <-- 01 August 2007

Previous message:
Subject: Re: difference density ripples around Hg atoms
From: Bart Hazes bart {- dot -} hazes {- at -} UALBERTA {- dot -} CA
Date: 2007-08-01

Next message:
Subject: Re: difference density ripples around Hg atoms
From: "George M {- dot -} Sheldrick" gsheldr {- at -} SHELX {- dot -} UNI-AC {- dot -} GWDG {- dot -} DE
Date: 2007-08-01