FIG. 1.

(A) Overall structure of HIV-1 PR showing the positions of the insertions (amino acid residues 33 and 35). The PR monomers are depicted in ribbon representation and are colored blue to red from the N terminus to the C terminus; Cα atoms of residues which are duplicated by insertion are shown as spheres and labeled. (B) HIV PR sequences of the corresponding mutant PRs with insertions (PR1 and PR3) and without insertions (PR2 and PR4) compared to the consensus B sequence. Primary resistance mutations (according to the International AIDS Society list, 2006 [current version available at http://www.iasusa.org/resistance_mutations/mutations_figures.pdf]) are shaded.