Re: [ccp4bb] MAD and twinning

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

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Subject: Re: MAD and twinning
From: Philippe DUMAS p {- dot -} dumas {- at -} IBMC {- dot -} U-STRASBG {- dot -} FR
Date: 2007-04-24

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From: Mischa Machius Mischa {- dot -} Machius {- at -} UTSOUTHWESTERN {- dot -} EDU
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Subject: Re: MAD and twinning
From: Petrus H Zwart PHZwart {- at -} LBL {- dot -} GOV
Date: 2007-04-24

> So one obvious questions: was your crystal fully bathed in the beam ?
> If not: would be interesting to try having a look at the unmerged
> data...Well, easier to suggest than to do...

I recall being frowned upon by my former supervisor (a small molecule crystallographer) for having crystals larger than the beam and for looking at fishnets ....

In any case, xtriage will detwin data with anomalous signal properly. download the latest version from www.phenix-online.org (either cci_apps or the latest phenix development release)

Note that according to Dauter (sorry, i forgot the reference), finding a substructure in twinned data is usually not a problem (given reasonable data). Improvement on the density modification according to Dauter can be obtained by performing density modification on detwinned data.

HTH

Peter

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

Previous message:
Subject: Re: MAD and twinning
From: Philippe DUMAS p {- dot -} dumas {- at -} IBMC {- dot -} U-STRASBG {- dot -} FR
Date: 2007-04-24

Next message:
Subject: Mac Pro questions
From: Mischa Machius Mischa {- dot -} Machius {- at -} UTSOUTHWESTERN {- dot -} EDU
Date: 2007-04-24