Characterization of a novel pestivirus originating from a pronghorn antelope

A unique pestivirus, isolated from a pronghorn antelope ( Antilocopra americana), was characterized. Serum neutralization studies suggested that this virus was antigenically related to pestiviruses. Genomic characteristics, unique to pestiviruses, indicated that this virus belongs to the Pestivirus genus. These characteristics included the organization of the 5′ untranslated region (5′-UTR), the presence and length of a viral N pro coding region, conservation of cysteine residues in N pro, conservation of predicted amino acid sequences flanking the cleavage sites between viral polypeptides N pro and C and between C and E rns and conservation of predicted hydrophobicity plots of N pro protein. While this data indicated the virus belongs to the Pestivirus genus, phylogenetic analysis in 5′-UTR, N pro and E2 regions suggested that it is the most divergent of the pestiviruses identified to date. This conclusion was also supported by the amino acid identity in coding regions. The corresponding values were much lower for the comparison of pronghorn pestivirus to other pestivirus genotypes than only between previous recognized genotypes. These results suggest the virus isolated from pronghorn antelope represents a new pestivirus genotype. It also represents the only pestivirus genotype first isolated from New World wildlife.