friedric at techfak.uni-bielefeld.de
Fri Apr 21 07:03:23 EST 1995
I would like to invitate all those of you, that are working on
the fields of protein-protein-docking, molecular surfaces,
energy evaluation, electrostatic interactions in proteins etc.
to a little comparison of some results. Especially I would like
to compare the shape (geometry) of m o l e c u l a r
a c c e s s i b l e s u r f a c e s (MS) with each other. In
addition, values of the electrostatic potential on the MS should
It is n o t intended to decide about the correctness of
underlying theoretical models, but rather to give all participants
a hint, how their results compare empirically with those of others.
I am working on the problem of protein-protein-docking. The main
idea of our project is to integrate geometrical and chemical
surface features in the evalutation of complementarity in an
easy and fast manner. To this end I am developing a class library
(C++) to calculate and manipulate protein features and features
of the molecular surfaces. One of this features is the electrostatic
potential on the surface. Now, the question arises: Am I computing
the right values?
Assume you can calculate the MS of a protein and possibly the
electrostatic potential on it, i.e. you should be able to write down
a file similar to this:
x1 y1 z1 e1
x2 y2 z2 e2
x3 y3 z3 e3
x4 y4 z4 e4
xN yN zN eN
Hereby, xi, yi, zi, and ei are floats. xi, yi, and zi are the
coordinates (in Aengstroem, given in the coordinate system of the
PDB - entry) of a surface point and ei is the
electrostatic potential that you computed at this particular
surface point. Since we compare only relative values, it is not
important in which unit ei is given.
Your MS will be sampled in a 3D grid (isotropic lattice constants
0.5, 0.8, and 1.2 Aengstroem will be used) and by counting hits and
missing voxels we will compare the shape (geometry) of the
different MSs. In a similar way we will compare by correlation on
the grid the values for the electrostatic potential on the MS.
You want to make one of the party?
Then please send me a note (friedric at techfak.uni-bielefeld.de)
(Name, institution, type of program you use, additional hints for
the comparison, references).
First all participants will be informed about the IDs of the others
and will receive a detailed description of the procedures used for
Then the PDB-IDs of some proteins I suggest to use for comparison
and a description of possible file formats will be sent.
Afterwords you will calculate the MS and eventually the potential
on it and you will send it to me. The comparisons will be performed,
and the results will be posted to all participants as a set of upper
triangular matrices, containing cross correlations and similar values
of every MS with each other.
In addition the results will be compiled to a technical report, that
will be made electronically available on our ftp server.
5.5.1995 Deadline for note on intended participation.
10.5.1995 Posting of PDB-Ids and format descriptions.
(Meanwhile eventually changes in procedure of
comparisons, depending on hints of participants.)
24.5.1995 Deadline for submission of MS
31.5.1995 Posting of results
I would be glad to here from you!
THIS NOTE WAS POSTED BY ME ORIGINALLY TO THE FOLLOWING NEWSGROUPS:
PLEASE FORWARD IT TO POSSIBLY INTERESTED PERSONS, THAT DON'T READ
PLEASE INFORM ME ABOUT OTHER NEWSGROUPS, INTO WHICH I SHOULD POST
IN ADDITION IT WAS POSTED TO
chemistry at osc.edu (hint from Max Vasquez)
bionet.xtallography (hint from Matthias Dreyer)
Applied Computer Science
Phone: +49 521 106 2938
Fax: +49 521 106 2992
email: friedric at techfak.uni-bielefeld.de
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