>
> Remember that phi-psi angels are excellent for validation purposes,
> but only when they are unrestrained, so if you restrain them you
> lose this option.
The above is a very important point!
Having now said that, restraining alpha-helices hydrogen bonding, and
beta-sheet cross-strand hydrogen bonds, can be done in REFMAC, Phenix
and CNS (its documented for all of them). This seems to be easier to
do and helpful, but has to be done with care - like everything in low
resolution refinement.
A.
>
>
> Hope this helps.
> -Bjørn
> --
> Bjørn Pañella Pedersen
> Ph.D Student, MSc
>
> Department of Molecular Biology Office: +45 89425021
> University of Aarhus Lab: +45 89425010
> Gustav Wieds Vej 10c Email: [log in to unmask]
> DK-8000 Aarhus C Lab WWW: http://www.bioxray.dk
> Denmark
>
> Mario Milani wrote:
>> Hi,
>> it could be really useful in refining low resolution structure
>> (with poor electron density map) to have a refinement program that
>> can restrain phi and psi angles to follow Ramachandran plot. Does
>> anyone know if such program exist?
>> Thank you,
>> mario
>> Mario Milani, PhD
>> University of Milan
>> Dep. of Biomol. Science and Biotech.
>> Via Celoria 26, 20133 Milan, Italy
>> T. +39 0250314892-4
>> F. +39 0250314895
>> http://digilander.libero.it/mario.milani/
>> http://users.unimi.it/biolstru/Home.html
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