1a6t
From Proteopedia
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FAB FRAGMENT OF MAB1-IA MONOCLONAL ANTIBODY TO HUMAN RHINOVIRUS 14 NIM-IA SITE
Overview
The structures of three different human rhinovirus 14 (HRV14)-Fab, complexes have been explored with X-ray crystallography and cryoelectron, microscopy procedures. All three antibodies bind to the NIm-IA site of, HRV14, which is the beta-B-beta-C loop of the viral capsid protein VP1., Two antibodies, Fab17-IA (Fab17) and Fab12-IA (Fab12), bind bivalently to, the virion surface and strongly neutralize viral infectivity whereas, Fab1-IA (Fab1) strongly aggregates and weakly neutralizes virions. The, structures of the two classes of virion-Fab complexes clearly differ and, correlate with observed binding neutralization differences. Fab17 and, Fab12 bind in essentially identical, tangential orientations to the viral, surface, which favors bidentate binding over icosahedral twofold axes., Fab1 binds in a more radial orientation that makes bidentate binding, unlikely. Although the binding orientations of these two antibody groups, differ, nearly identical charge interactions occur at all paratope-epitope, interfaces. Nucleotide sequence comparisons suggest that Fab17 and Fab12, are from the same progenitor cell and that some of the differing residues, contact the south wall of the receptor binding canyon that encircles each, of the icosahedral fivefold vertices. All of the antibodies contact a, significant proportion of the canyon region and directly overlap much of, the receptor (intercellular adhesion molecule 1 [ICAM-1]) binding site., Fab1, however, does not contact the same residues on the upper south wall, (the side facing away from fivefold axes) at the receptor binding region, as do Fab12 and Fab17. All three antibodies cause some stabilization of, HRV14 against pH-induced inactivation; thus, stabilization may be mediated, by invariant contacts with the canyon.
About this Structure
1A6T is a Protein complex structure of sequences from Mus musculus. Full crystallographic information is available from OCA.
Reference
Antibody-mediated neutralization of human rhinovirus 14 explored by means of cryoelectron microscopy and X-ray crystallography of virus-Fab complexes., Che Z, Olson NH, Leippe D, Lee WM, Mosser AG, Rueckert RR, Baker TS, Smith TJ, J Virol. 1998 Jun;72(6):4610-22. PMID:9573224
Page seeded by OCA on Sun Nov 18 09:25:26 2007
