Nucleotide sequence analysis of the ovine respiratory syncytial virus G glycoprotein gene

Respiratory syncytial virus (RSV) infects humans and animals including ruminants. Among the 10 genes coded for in the viral genome, the putative attachment glycoprotein G gene has been the most variable among strains. Human RSV have been divided to two subgroups based on immunological and base sequence data on the attachment glycoprotein G and its gene, respectively. It has been suggested that similar antigenic diversity also exists among bovine RSV (BRSV) isolates. In this study, we report on the cloning and sequencing of the G glycoprotein from an ovine RSV (ORSV) strain originally isolated from a naturally infected sheep with rhinitis. This ORSV G glycoprotein gene had greater identity to the BRSV G gene than to the human RSV G gene. ORSV G gene and its encoded protein shared 70 and 62% nucleotide and amino acid identity to the equivalent gene and encoded protein, respectively, of BRSV but, in contrast, only 50-55% and 21-29% identity, respectively, to equivalent sequences of the HRSV strains. The relationship of the ORSV to other RSV subgroups and the possibility that ORSV could be a subgroup of the ruminant RSV is discussed.