Figure 3.

Genetic barrier influences the emergence of amino acid mutations but not impact of mutations on viral infectivity: (A) Number of nucleotide changes required for mutations observed and not observed in the HIV database of 5811 sequences; (B) Number of nucleotide changes required for mutations whose impact on infectivity was tested; amino acid mutations classified into three groups based on their frequency in the HIV database with stability predicted by DOPE (C) and FOLDEF (D) using the mature CA hexamer as the template.