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The structure of human rhinovirus 14 has been refined, by the method of
restrained least squares, to an R factor of 0.16 for various random samples
between 6 and 3 A resolution with F greater than 3 sigma (F). As a first step
the non-crystallographic symmetry parameters were optimized using the initial
atomic model in a rigid-body refinement procedure. Phase determination by the
molecular-replacement phase extension and refinement procedure was continued to
2.94 A resolution, employing the improved non-crystallographic symmetry
operators. The resultant structure-factor phases and weights, together with the
measured amplitudes, constituted the X-ray observations used in the restrained
refinement. The Hendrickson-Konnert program system [Konnert & Hendrickson
(1980). Acta Cryst. A36, 344-350] was modified to incorporate
non-crystallographic symmetry constrains and structure-factor phases as
observations. The non-bonded contacts between subunits related by
non-crystallographic symmetry were also restrained.
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