Identification of a newly described OsHV-1 µvar from the North Adriatic Sea (Italy)

J Gen Virol. 2018 May;99(5):693-703. doi: 10.1099/jgv.0.001042. Epub 2018 Mar 26.

Abstract

The surveillance activities for abnormal bivalve mortality events in Italy include the diagnosis of ostreid herpesvirus type 1 (OsHV-1) in symptomatic oysters. OsHV-1-positive oysters (Crassostrea gigas) were used as a source for in vivo virus propagation and a virus-rich sample was selected to perform shotgun sequencing based on Illumina technology. Starting from this unpurified supernatant sample from gills and mantle, we generated 3.5 million reads (2×300 bp) and de novo assembled the whole genome of an Italian OsHV-1 microvariant (OsHV-1-PT). The OsHV-1-PT genome encodes 125 putative ORFs, 7 of which had not previously been predicted in other sequenced Malacoherpesviridae. Overall, OsHV-1-PT displays typical microvariant OsHV-1 genome features, while few polymorphisms (0.08 %) determine its uniqueness. As little is known about the genetic determinants of OsHV-1 virulence, comparing complete OsHV-1 genomes supports a better understanding of the virus pathogenicity and provides new insights into virus-host interactions.

Keywords: Crassostrea gigas; OsHV-1-PT; Ostreid herpesvirus type 1 μVar; complete genome; de novo assembly; next generation sequencing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Crassostrea / virology*
  • DNA Viruses / classification*
  • DNA Viruses / isolation & purification
  • DNA Viruses / pathogenicity
  • DNA, Viral / isolation & purification
  • Genome, Viral*
  • Italy
  • Open Reading Frames
  • Phylogeny
  • Polymorphism, Genetic

Substances

  • DNA, Viral

Supplementary concepts

  • Ostreid herpesvirus 1