[ccp4bb] Restraint hydrogen bond Refmac

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

Previous message:
Subject: Re: detergent crystals
From: Jason Hurlbert hurlbertj {- at -} WINTHROP {- dot -} EDU
Date: 2009-08-05

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Subject: Re: Restraint hydrogen bond Refmac
From: Ian Tickle I {- dot -} Tickle {- at -} ASTEX-THERAPEUTICS {- dot -} COM
Date: 2009-08-05

Subject: Restraint hydrogen bond Refmac
From: Kristof Van Hecke Kristof {- dot -} VanHecke {- at -} CHEM {- dot -} KULEUVEN {- dot -} BE
Date: 2009-08-05

Dear,

When (trying) to refine a DNA-structure (resolution 2.5) using
Refmac_5.5.0072 (CCP4 6.1.1), some of the H-bonds between Watson-
Crick bases are becoming too large.

Reducing the Matrix weighting term to tighten the geometry, doesn't
effect these H-bond distances much.
Reducing the "VDW SIGMA HBOND" also doesn't solve the problem.

Adding "external distance restraints" does the trick, but some B-
factors (not the ones involved in H-bonding!) blow up completely.

Hence, what's actually the best way of tighten H-bond restraints in
Refmac, or am I overlooking some other issues here..?

Thank you very much.

Regards

Kristof Van Hecke

--------------------------------------
Kristof Van Hecke, PhD
Biomoleculaire Architectuur
Celestijnenlaan 200 F
B-3001 Heverlee (Leuven)
Tel: +32(0)16327477
--------------------------------------

CCP4bb navigation

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

Previous message:
Subject: Re: detergent crystals
From: Jason Hurlbert hurlbertj {- at -} WINTHROP {- dot -} EDU
Date: 2009-08-05

Next message:
Subject: Re: Restraint hydrogen bond Refmac
From: Ian Tickle I {- dot -} Tickle {- at -} ASTEX-THERAPEUTICS {- dot -} COM
Date: 2009-08-05