title: A novel class of herpesvirus with bivalve hosts.
abstract: Ostreid herpesvirus 1 (OsHV-1) is the only member of the Herpesviridae that has an invertebrate host and is associated with sporadic mortality in the Pacific oyster (Crassostrea gigas) and other bivalve species. Cryo-electron microscopy of purified capsids revealed the distinctive T=16 icosahedral structure characteristic of herpesviruses, although the preparations examined lacked pentons. The gross genome organization of OsHV-1 was similar to that of certain mammalian herpesviruses (including herpes simplex virus and human cytomegalovirus), consisting of two invertible unique regions (U(L), 167.8 kbp; U(S), 3.4 kbp) each flanked by inverted repeats (TR(L)/IR(L), 7.6 kbp; TR(S)/IR(S), 9.8 kbp), with an additional unique sequence (X, 1.5 kbp) between IR(L) and IR(S). Of the 124 unique genes predicted from the 207 439 bp genome sequence, 38 were members of 12 families of related genes and encoded products related to helicases, inhibitors of apoptosis, deoxyuridine triphosphatase and RING-finger proteins, in addition to membrane-associated proteins. Eight genes in three of the families appeared to be fragmented. Other genes that did not belong to the families were predicted to encode DNA polymerase, the two subunits of ribonucleotide reductase, a helicase, a primase, the ATPase subunit of terminase, a RecB-like protein, additional RING-like proteins, an ion channel and several other membrane-associated proteins. Sequence comparisons showed that OsHV-1 is at best tenuously related to the two classes of vertebrate herpesviruses (those associated with mammals, birds and reptiles, and those associated with bony fish and amphibians). OsHV-1 thus represents a third major class of the herpesviruses.
authors.affiliation: MRC Virology Unit, Institute of Virology, Church Street, Glasgow G11 5JR, UK.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Davison
authors.affiliation: Laboratory of Structural Biology, National Institute of Arthritis, Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA.|Imaging Sciences Laboratory, Center for Information Technology, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Benes L
authors.initials: BL
authors.lastname: Trus
authors.affiliation: Laboratory of Structural Biology, National Institute of Arthritis, Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Naiqian
authors.initials: N
authors.lastname: Cheng
authors.affiliation: Laboratory of Structural Biology, National Institute of Arthritis, Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Alasdair C
authors.initials: AC
authors.lastname: Steven
authors.affiliation: MRC Virology Unit, Institute of Virology, Church Street, Glasgow G11 5JR, UK.
authors.forename: Moira S
authors.initials: MS
authors.lastname: Watson
authors.affiliation: MRC Virology Unit, Institute of Virology, Church Street, Glasgow G11 5JR, UK.
authors.forename: Charles
authors.initials: C
authors.lastname: Cunningham
authors.affiliation: Laboratoire de Génétique et Pathologie, IFREMER, 17390 La Tremblade, France.
authors.forename: Rose-Marie Le
authors.initials: RL
authors.lastname: Deuff
authors.affiliation: Laboratoire de Génétique et Pathologie, IFREMER, 17390 La Tremblade, France.
authors.forename: Tristan
authors.initials: T
authors.lastname: Renault
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002213:Capsid / Q000737:chemistry; D004265:DNA Helicases / Q000235:genetics; D016679:Genome, Viral; D006564:Herpesviridae / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D051034:Inhibitor of Apoptosis Proteins; D007814:Larva / Q000821:virology; D008565:Membrane Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D010125:Ostreidae / Q000821:virology*; D011506:Proteins / Q000235:genetics; D011755:Pyrophosphatases / Q000235:genetics; D016415:Sequence Alignment
chemical_list: D051034:Inhibitor of Apoptosis Proteins; D008565:Membrane Proteins; D011506:Proteins; D011755:Pyrophosphatases; C020020:dUTP pyrophosphatase; D004265:DNA Helicases