FIG. 4.

Protease inhibitor susceptibility of matrix constructs with single mutations or pairs of mutations, all with wild-type protease. Susceptibility is shown as described in the legend to Fig. 3. Error bars represent the standard error of the mean from two separate experiments. (A) PI susceptibility of single mutations to aa 76, 79, and 81 of matrix (8MA76K, 8MA79F, and 8MA81A, respectively), shown by an asterisk in the schematics. (B) PI susceptibility of pairs of mutations (8MA76K79F, 8MA76K81A, and 8MA79F81A), shown by gray ovals in an otherwise white (wild-type) background.