CRYSTALLIZATION AND STRUCTURE DETERMINATION OF THE Fab FRAGMENT OF AN ANTIBODY AGAINST HUMAN RHINOVIRUS

Since our group decided to start structural studies on proteins by x-ray crystallography in 1986, we have obtained crystals suitable for high re-solutio x-ray analysis of two different proteins: catalase HPII from Esche-richia coli ' and a Fab fragment of a monoclonal antibody directed against human rhinovirus serotype 2. During the last year (1990), we have com-pleted the resolution of the three dimensional structure for the Fab frag-ment at 3.0 A resolution. This is the first protein structure solved by x-ray crystallography in Spain. BACKGROUND Rhinoviruses can be divided into two distinct groups according to their specific receptor binding: the major group, to which at least 78 sero-types (including HRV14) belong, and the minor group, representing at least 10 serotypes (including HRVIA and HRV2). The structures of two serotypes (HRV14, HRVIA) have been determined by x-ray crystallo-graphic studies to about 3-A resolution.2, ' Based on the structure of HRV14, a model for the HRV2 structure has been proposed.&apos