Structure Determination of an Fab Fragment that Neutralizes Human Rhinovirus 14 and Analysis of the Fab-Virus Complex

• Published in: Journal of molecular biology Vol. 240; no. 2; pp. 127 - 137
• Main Authors: Liu, Hansong, Smith, Thomas J., Lee, Wai-ming, Mosser, Anne G., Rueckert, Roland R., Olson, Norman H., Cheng, R.Holland, Baker, Timothy S.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 08.07.1994
• Subjects: Amino Acid Sequence; Antibodies, Monoclonal - chemistry; Antibodies, Monoclonal - immunology; Antibodies, Viral - chemistry; Antibodies, Viral - immunology; Antigen-Antibody Complex - chemistry; Antigen-Antibody Complex - immunology; Antigen-Antibody Complex - ultrastructure; Base Sequence; Cryopreservation; crystallography; Crystallography, X-Ray; Fab—virus complex; human rhinovirus; Humans; immunoglobulin; Immunoglobulin Fab Fragments - chemistry; Immunoglobulin Fab Fragments - immunology; Immunoglobulin Fab Fragments - ultrastructure; Microscopy, Electron; Models, Molecular; Molecular Sequence Data; neutralization; Neutralization Tests; Protein Conformation; Rhinovirus - chemistry; Rhinovirus - immunology; Rhinovirus - ultrastructure; Sequence Homology, Amino Acid; Structure-Activity Relationship; human rhinovirus; crystallography; Fab—virus complex; immunoglobulin; neutralization
• ISSN: 0022-2836; 1089-8638
• DOI: 10.1006/jmbi.1994.1427

The crystal structure of Fab17-IA, an antigen-binding fragment from a murine immunoglobulin that neutralizes human rhinovirus 14 (HRV14), has been solved to 2·7 Å resolution. Fab17-IA crystallized into three different space groups depending upon the method used to purify the intact antibody. The structure was determined by use of molecular and isomorphous replacement methods. The current model has a crystallographic R-factor of ∼19% for 10,192 independent reflections between 8 and 2·7 Å. Correlation coefficient calculations showed that the Fab17-IA structure can be fit into the Fab17-IA/HRV14 image reconstruction density to within 5 Å positional accuracy and to within a few degrees of rotation. The resulting interface of the docked antibody was examined and showed extensive charge and shape complementarity with the virus surface that was supported by site-directed mutagenesis experiments. The success of this approach validates the utility of combining X-ray crystallography with cryo-electron microscopy of complex macromolecular assembles.