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

• Published in: Journal of General Virology
• Main Authors: Abbadi, Miriam, Zamperin, Gianpiero, Gastaldelli, Michele, Pascoli, Francesco, Rosani, Umberto, Milani, Adelaide, Schivo, Alessia, Rossetti, Emanuele, Turolla, Edoardo, Gennari, Lorenzo, Toffan, Anna, Arcangeli, Giuseppe, Venier, Paola
• Format: Text
• Language: English
• Published: Microbiology Society 2018
• Subjects: Short Communication; Crassostrea gigas
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5994699/; http://www.ncbi.nlm.nih.gov/pubmed/29580370; https://doi.org/10.1099/jgv.0.001042

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.