Fig. 6.

Statistically divergent positions between X4 and R5 HIV-1 Tat interchange amino acids for those with similar physiochemical properties. The amino acid usage in four HIV-1 Tat amino acid positions (7, 23, 57, and 60) was plotted for both R5 and X4 groups as a stacked bar chart representing the total genetic variation within each population at the respective positions. Amino acids were color coded according to physiochemical property using the following scheme: positively charged (red), negatively charged (blue), polar uncharged (purple), hydrophobic (green), and unclassified (glycine, proline, and cysteine, yellow). The amino acid positions 7, 23, 57, and 60 were selected due to their statistically significant Jensen–Shannon divergence