Molecular characterization of a novel bovine group A rotavirus

Abstract

In this study, by partial sequence analysis of the genome segments encoding VP5* and VP7, we characterized a novel bovine group A rotavirus, namely, Tak2, that was detected from adult cattle diarrhea in Tochigi Prefecture, Japan. The nucleotide (nt) and deduced amino acid (aa) sequences of the genome segments encoding VP5* and half of the amino terminal portion of VP7 of Tak2 revealed a low identity with those of group A rotaviruses carrying previously published P and G type specificities (VP5*: nt identity, 61.6%-67.6% and aa identity, 58.0%-71.4%; half of the amino terminal portion of VP7: nt identity, 57.8%-73.5% and aa identity, 61.2%-70.9%). Additionally, phylogenetic analysis of the nt sequences of the genome segments encoding VP5* and half of the amino terminal portion of VP7 revealed that Tak2 formed a branch separate from the established P and G types. These results suggested that Tak2 could possess novel P and G types yet not reported among group A rotaviruses.

Fig. 1

The phylogenetic tree constructed by the neighbor-joining method, using the nucleotide sequences of the genome segments encoding VP5* of the reference strains and Tak2, which is indicated in boldface. The accession numbers of the reference strains are listed in Table 1. The percentage bootstrap values are shown at the branch nodes. The scale bar represents 10% nucleotide difference. P genotypes are indicated after the strain names.

Fig. 2

The phylogenetic tree constructed by the neighbor-joining method, using the nucleotide sequences of the genome segments encoding half of the amino terminal portion of VP7 of reference strains and Tak2, which is indicated in boldface. The accession numbers of the reference strains are listed in Table 2. The percentage bootstrap values are shown at the branch nodes. The scale bar represents 10% nucleotide difference. The G types are indicated after the strain names.