Sequence analysis of RNA-2 of different isolates of broad bean wilt virus confirms the existence of two distinct species

Summary

The complete nucleotide sequence of RNA-2 from a Japanese isolate IP of broad bean wilt virus (BBWV) was determined. The sequence encodes a single large polyprotein, which contains a putative movement protein and two coat proteins (CPs). The 3′-terminal sequences of RNA-2 were also determined for three other Japanese isolates and two ATCC isolates (PV132 and PV176) of BBWV. The CPs of the four Japanese isolates share 86.8–98.0% amino acid sequences homology with one another and 88.3–96.5% with those reported for the isolate PV131 (BBWV-2). However, they have only 57.9–66.2% homology with those of PV132 and PV176 (BBWV-1).