Near-atomic resolution structure of a highly neutralizing fab bound to canine parvovirus

Lindsey J. Organtini, Hyunwook Lee, Sho Iketani, Kai Huang, Robert E. Ashley, Alexander M. Makhov, James F. Conway, Colin R. Parrish, Susan Hafenstein

Research output: Contribution to journalArticle

11 Scopus citations

Abstract

Canine parvovirus (CPV) is a highly contagious pathogen that causes severe disease in dogs and wildlife. Previously, a panel of neutralizing monoclonal antibodies (MAb) raised against CPV was characterized. An antibody fragment (Fab) of MAb E was found to neutralize the virus at low molar ratios. Using recent advances in cryo-electron microscopy (cryo-EM), we determined the structure of CPV in complex with Fab E to 4.1 Å resolution, which allowed de novo building of the Fab structure. The footprint identified was significantly different from the footprint obtained previously from models fitted into lower-resolution maps. Using single-chain variable fragments, we tested antibody residues that control capsid binding. The near-atomic structure also revealed that Fab binding had caused capsid destabilization in regions containing key residues conferring receptor binding and tropism, which suggests a mechanism for efficient virus neutralization by antibody. Furthermore, a general technical approach to solving the structures of small molecules is demonstrated, as binding the Fab to the capsid allowed us to determine the 50-kDa Fab structure by cryo-EM.

Original languageEnglish (US)
Pages (from-to)9733-9742
Number of pages10
JournalJournal of Virology
Volume90
Issue number21
DOIs
StatePublished - Jan 1 2016
Externally publishedYes

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ASJC Scopus subject areas

  • Microbiology
  • Immunology
  • Insect Science
  • Virology

Cite this

Organtini, L. J., Lee, H., Iketani, S., Huang, K., Ashley, R. E., Makhov, A. M., Conway, J. F., Parrish, C. R., & Hafenstein, S. (2016). Near-atomic resolution structure of a highly neutralizing fab bound to canine parvovirus. Journal of Virology, 90(21), 9733-9742. https://doi.org/10.1128/JVI.01112-16