Diagnosis, Phylogenetic analysis and cloning of G glycoprotein gene of viral hemorrhagic septicemia virus (VHSV) detected in Rainbow trout (Onchorhynchus mykiss)

Viral hemorrhagic septicemia is one of the most important virus disease in salmonid fishes. The genome of the virus consists of six genes, the most important of which is the G glycoprotein gene, which plays a role in immunization against the virus. The aim of this study was detection of viral hemorrhagic septicemia virus in Rainbow trout, phylogenic study and cloning of the G gene of virus in pTZ57r/t vector.

After detecting of viral hemorrhagic septicemia virus by RT-PC, cloning of G gene in pTZ57r/t plasmid, the recombinant plasmid was transformed to the competent bacterium (E. coli). White clonies containing recombinant vector were used to extract the plasmid. The size of the G gene of viral hemorrhagic septicemia virus was 1523 bp. In this study, colony PCR method and sequencing were used to confirm the cloning.

The results of this study showed that G gene has been cloned successfully in pTZ57r/t vector and can be used to express the glycoprotein of the virus in expression vectors for protein production. The results of sequencing of G gene also showed that the virus identified in this study belonged to genotype Ia-2.