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Crystal structure of Lyme disease antigen outer surface protein A complexed with an Fab.

ABSTRACT: OspA (outer surface protein A) is an abundant immunogenic lipoprotein of the Lyme disease spirochete Borrelia burgdorferi. The crystal structure of a soluble recombinant form of OspA was solved in a complex with the Fab fragment of mouse monoclonal antibody 184.1 and refined to a resolution of 1.9 A. OspA has a repetitive antiparallel beta topology with an unusual nonglobular region of "freestanding" sheet connecting globular N- and C-terminal domains. Arrays of residues with alternating charges are a predominant feature of the folding pattern in the nonglobular region. The 184.1 epitope overlaps with a well conserved surface in the N-terminal domain, and a hydrophobic cavity buried in a positively charged cleft in the C-terminal domain is a potential binding site for an unknown ligand. An exposed variable region on the C-terminal domain of OspA is predicted to be an important factor in the worldwide effectiveness of OspA-based vaccines.

SUBMITTER: Li H

PROVIDER: S-EPMC20483 | biostudies-literature | 1997 Apr

REPOSITORIES: biostudies-literature

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Crystal structure of Lyme disease antigen outer surface protein A complexed with an Fab.

Li H H Dunn J J JJ Luft B J BJ Lawson C L CL

Proceedings of the National Academy of Sciences of the United States of America 19970401 8

OspA (outer surface protein A) is an abundant immunogenic lipoprotein of the Lyme disease spirochete Borrelia burgdorferi. The crystal structure of a soluble recombinant form of OspA was solved in a complex with the Fab fragment of mouse monoclonal antibody 184.1 and refined to a resolution of 1.9 A. OspA has a repetitive antiparallel beta topology with an unusual nonglobular region of "freestanding" sheet connecting globular N- and C-terminal domains. Arrays of residues with alternating charges ...[more]

PMID: 9108020

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