Fig. 5

Variant analysis of the envelope proteins of dengue virus (all four serotypes) and HIV-1 clade B. a Density plots for the incidence of total variants of the index nonamer and the entropy of the nonamer sequences for the envelope proteins of dengue virus (all four serotypes) and HIV-1 clade B. The variants incidence is widely distributed for HIV-1 clade B, whereas for dengue it is mainly localized in the higher range, with very few positions (6%) under the 20% incidence region (dotted line). b Density plots for the incidence of all variants to the index nonamer and the major variant at each nonamer position for the envelope proteins of dengue virus (all four serotypes) and HIV-1 clade B. The boxed regions and the adjacent values indicate the fraction and number of total nonamer positions analyzed that are highly conserved, contain fewer than 20% variants of the index sequence and fewer than 10% incidence of the major variant. Despite the lower overall entropy of dengue virus (all four serotypes) compared to HIV-1 clade B, only 2% (9 nonamer sites) of the dengue virus envelope nonamers satisfied this criteria, while more favourable targets (9%; 80 nonamer sites) are present for the envelope of HIV-1 clade B