Identificação e caracterização de um potyvírus isolado de Zinnia elegans

Biological and molecular characterisation of Bidens mosaic virus supports its assignment as a member of a distinct species in the genus Potyvirus

The complete nucleotide (nt) sequence of Bidens mosaic virus (BiMV) isolate SP01 was determined and shown to consist of 9,557 nt. Since it shared highest identities in the nt sequence of the whole genome (66-73 %) and in the aa sequence of the polyprotein (60-76 %) with viruses of the potato virus Y subgroup, it was compared with them genetically and biologically. Phylogenetic analysis showed that the closest relative of BiMV is sunflower chlorotic mottle virus, from which it, however, differed significantly in various respects. These results indicate that BiMV should represent a distinct species in the genus Potyvirus.

Bidens mosaic virus is a member of the Potato virus Y species

The nucleotide sequence of the genomic 3' terminal region (1,702 bases) of two Brazilian Bidens mosaic virus isolates (BiMV: BiMV-p and BiMV-b) was determined. BiMV-p and BiMV-b share 98% nucleotide sequence identity, and are most closely related to members of the potyvirus species: Sunflower chlorotic mottle virus (an isolate of Potato virus Y) and Potato virus Y. BiMV-p shares 88% capsid protein amino acid identity and 77% 3'UTR nucleotide sequence identity with SuCMoV an isolate of Sunflower chlorotic mottle virus. Phylogenetic analyses suggest the close evolutionary relationship of BiMV, SuCMoV and Potato virus Y (PVY), members of the PVY species. According to the analyses of capsid protein and 3'UTR sequences BiMV isolates must be regarded as a strain of Potato virus Y species, but their differences in host reactions and the phylogenetic distance suggest that they would be most likely better placed in a taxon between species and strains.