STRUCTURE OF HUMAN RHINO VIRUS 50 AT 1.8 Å E. Blanc¹, R. S. Alexander², M. McMillan³, D. C. Pevear⁴, V. Giranda⁵, M. S. Chapman¹, ¹Institute for Molecular Biophysics and Department of Chemistry, Florida State University, Tallahassee, Fl 32306, ²Dupont Merck Pharmaceutical Co., Wilmington, De 19880, ³Eastman Kodak Co., Rochester, NY 14650, ⁴Viropharma Inc., Malvern, Pa 19335, ⁵Abbott Laboratories, Abbott Park, Il 60064-3500

Human Rhino Virus 50 (HRV50) belongs to one of the largest and most important families of viral pathogens: the picornaviridae. Rhinoviruses are among the smallest RNA-containing viruses; their genome is surrounded by a protein shell made of 60 copies of the asymmetric unit, each containing 4 polypeptide chains. As the major cause of the common cold, these viruses have already been extensively studied, and several structures have been determined. HRV50 is of special interest for two reasons: firstly, it is one of the more representative serotypes, of use in the design of broad spectrum drugs against all rhinoviruses. Secondly, there is the opportunity to study the structure and drug interactions at unusually high resolution, 1.8 Å.

The structure refinement has been performed mainly in real-space, using a new technique [Chapman (1995) Acta Crystallogr. A51: 69-80] that accounts for the resolution of the experimental data, and can be 50 times faster than conventional reciprocal-space refinement. The method takes advantage of accurate phases that result from application of 15-fold non-crystallographic symmetry. Moreover, the method makes it tractable to refine such large structures against all experimental data simultaneously. Prior comparaisons [Chapman & Rossman (1996) Acta Crystallogr. D: in press] with canine parvovirus have demonstrated that the quality of a real-space refined virus is at least as good as refined in reciprocal space.