Program Description: |
Curves is an algorithm for calculating a helical parameter
description for any irregular nucleic acid segment with respect to
an optimal, global helical axis.
Input geometry can come from a protein data bank file (.PDB or
.BRK), the Jumna program format (.MAC) or a general data file
(.DAT). In the latter case atoms should be specified, after an
initial title line, by giving the atom name, the XYZ coordinates,
the subunit name and the subunit number in the format
(a4,3f10.5,1x,a4,i4).
Curves produces text output with numerical values of helical
parameters. Curves can also ouput a file (in .PDB Brookhaven format
or in .MAC format) showing the helical axis system, the base
positions (represented by rectangles) and backbone ribbons, which
can be used for graphic representation of the results (this is
strongly encouraged). An option also exists to represent the local
helical axis segments individually, or to generate a spline smoothed
curve for the entire axis. Lastly, Curves can output the helicoidal
parameters in a concise form in a .DAF file which may be useful as
input to spreadsheet or others computer programs.
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