The bovine Newbury agent-2 is genetically more closely related to human SRSVs than to animal caliciviruses

Virology. 1999 Feb 1;254(1):1-5. doi: 10.1006/viro.1998.9514.


The hypothesis that the enteric bovine calici-like virus Newbury agent (NA-2) belongs to the family Caliciviridae was examined by genome sequence analysis. Use of solid-phase immune electron microscopy allowed samples with good levels of virus to be identified and amplification of the genome was achieved by reverse transcription-polymerase chain reaction. Examination of a 216-amino-acid sequence in the RNA-dependent RNA polymerase gene and a 116-amino-acid sequence in the capsid gene showed that NA-2 had the closest deduced amino acid identity (77 to 80% for the polymerase region and 67 to 73% for the capsid region) to the morphologically indistinguishable human SRSVs (small round structured viruses) of genogroup 1, which are classified as members of the Caliciviridae. It had a weak relationship (<34.5% deduced amino acid identity) in both the polymerase and the capsid regions to animal caliciviruses, all of which have classical morphology. This is the first genomic data from a nonhuman virus with SRSV morphology. It confirms the hypothesis that the bovine enteric calici-like virus NA-2 is a member of the family Caliciviridae and endorses the observation to date that viruses with SRSV morphology are genomically distinct.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Caliciviridae / classification*
  • Caliciviridae / enzymology
  • Caliciviridae / genetics
  • Caliciviridae / ultrastructure
  • Cattle
  • Genes, pol
  • Humans
  • Molecular Sequence Data
  • Norwalk virus / classification*
  • Norwalk virus / enzymology
  • Norwalk virus / genetics
  • Norwalk virus / ultrastructure

Associated data

  • GENBANK/AF097917
  • GENBANK/AF097918