Comparison of the coat protein genes of Mirafiori lettuce big-vein virus isolates from Australia with those of isolates from other continents.

The complete coat protein nucleotide encoding sequences of 13 Mirafiori lettuce big-vein virus isolates from Australia were compared to those of 23 other isolates, including one from Australia. On phylogenetic analysis, sub-clade A1 contained isolates from Australia (13), Europe and Japan, A2 contained isolates from Australia (1), Europe and South America, and B1 and B2 contained only European isolates. In the amino acid sequences deduced, the N-terminus and central regions varied considerably between clades A and B. Mean Dn/Ds ratios were 0.112, 0.076, 0.187 and 0.063 for all isolates, Australian isolates, clade A isolates and clade B isolates, respectively.