The Bovine Newbury Agent-2 Is Genetically More Closely Related to Human SRSVs Than to Animal Caliciviruses

• Published in: Virology (New York, N.Y.) Vol. 254; no. 1; pp. 1 - 5
• Main Authors: Dastjerdi, A.M., Green, J., Gallimore, C.I., Brown, D.W.G., Bridger, J.C.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.02.1999
• Subjects: Amino Acid Sequence; Animals; Bovine Newbury agent-2; Caliciviridae - classification; Caliciviridae - enzymology; Caliciviridae - genetics; Caliciviridae - ultrastructure; Calicivirus; Cattle; Genes, pol; Humans; Molecular Sequence Data; Norwalk virus - classification; Norwalk virus - enzymology; Norwalk virus - genetics; Norwalk virus - ultrastructure
• ISSN: 0042-6822; 1096-0341
• DOI: 10.1006/viro.1998.9514

The hypothesis that the enteric bovine calici-like virus Newbury agent (NA-2) belongs to the familyCaliciviridaewas 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 theCaliciviridae.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 familyCaliciviridaeand endorses the observation to date that viruses with SRSV morphology are genomically distinct.