Subject: Re: [modeller_usage] problem of strand/sheet
From: Modeller Caretaker <>
Date: Tue, 04 Mar 2008 12:45:00 -0500
Cc:
model model wrote:
I am trying to put secondary structure restraints (strand and sheet) to
the MODELLER modeling. However, I found that most of the specified
hydrogen-bonds
between strands have not been satisfied in the final model. I understand
that MODELLER tries to satisfy ALL the restraints and there
may be some conflicts between my hydrogen-bond and other restraints.
One thing to check is the .rsr file or the list of violated restraints,
to make sure it's actually trying to restrain the correct set of
hydrogen bonds. The syntax for secondary_structure.sheet() is easy to
get wrong, and Modeller does little sanity checking here.
My questions are: 1. do I have a way to make some restraints stronger than
other restraints? 2. do I have a way to force some important restraints
(like the beta-sheet) no matter whether they are conflicted with others?
Alternatively, you can edit the restraint file by hand and decrease the
standard deviations (no way to do this from the Python script currently).
2. Not directly; you'd have to identify the conflicting restraints
first, and either scale them down (if you can) or use
restraints.unpick() to unpick them and then restraints.condense() to
permanently remove them.