Genome analysis of viral hemorrhagic septicemia virus isolated from Paralichthys olivaceus in China

This study determined the complete genomic sequence of the viral hemorrhagic septicemia virus (VHSV) strain GY-2307 isolated form farmed paralichthys olivaceus in northeast China. The whole genome length of GY-2307 comprised 11,140 nucleotides (nt), and the overall organization was typical of that observed for all other VHSV strains. The phylogenetic analysis results indicated that the GY-2307 isolate belonged to genotype Ⅳa and significantly related to other Korean and Japanese isolates. The N, P, M, NV and L genes of GY-2307 were compared with the VHSV sequences in GenBank. The results revealed that 315 nt were substituted, 71 of which exhibited amino acid change in the GY-2307 genome. In the G gene, specific nucleotides and amino acid variations of the Chinese isolates of VHSV were observed when compared with 28 isolates from other counties. Of the 23 nucleotide sites that changed, 9 resulted in amino acid substitution. The data further indicated that the genotype Ⅳa VHSV was introduced to and evolved in paralichthys olivaceus farm environments in China.