FIG. 1.

Phylogenetic tree of the partial S gene of BCoV. The starting tree was generated via the neighbor-joining method. The topology and distances of the final tree were derived by the maximum-likelihood method, and the bootstrap values were calculated by the neighbor-joining method. Only bootstrap values (more than 70% of 1,000 replicates) are shown above the branches. The scale bar shows the number of substitutions per site. This is an unrooted tree, with HCoV OC43 used as an outgroup. The viruses retrieved from GenBank include wild-type respiratory strains (LSU 94LSS 051 2 and OK 05143) and enteric strains (Quebec BCQ.1523, Quebec BCQ.7373, and Mebus). The other sequences, which are identified in Table 1, clustered into two major groups: group I, with two subgroups (Ia and Ib), and group II.