Molecular Appraisal of the Host-Range K1L Gene of Buffalopox Virus Isolates from an Outbreak (2010) in Maharashtra

The buffalopox virus (BPXV) has emerged as an occupational zoonotic disease in the country. Host-range genes play a critical role in the host tropism of poxviruses as in the case of vaccinia viruses (VACV). Among hostrange genes, the K1L gene is required for viral replication by antagonising host-imposed interferon resistance. This study was undertaken for genetic characterisation of this VACV homologue host-range gene of BPXV isolates from buffaloes (BPXV/buffalo/Jalgaon/2010) and humans (BPXV/human/Jalgaon/2010) from an outbreak (2010) in Maharashtra. Furthermore, we also analysed the phylogenetic relationship of BPXVs with other Orthopoxviruses (OPXVs) to determine the nature of this gene within the genus. Sequence analysis revealed ORFs of 855 bp. Current isolates shared maximum homology (~99%) at both nt and aa levels with VACV. There was no sequence variation in this gene with respect to buffalo and human isolates of BPXV; however, a significant point mutation (D249N) was observed in the BPXV isolates as compared with VACV and other VACV-like viruses. Phylogenetic analysis revealed clustering of BPXV isolates with VACVs along with the vaccine strains. The close homology between BPXV and VACV suggests their similar roles in viral pathogenesis.This analysis could provide an avenue for discovering critical innate antiviral responses for the development of vaccine and antiviral agents required in the context of reduction of cohort immunity against poxviruses in the human population. This is the first report of genetic analysis of the K1L gene of the buffalopox virus.