FIG. 3.

(a) Outlying atoms of RO1 identified as protruding outside the substrate envelope. Atoms deviating by 1.4 to 2.0 Å and greater than 2.0 Å are distinguished in red and yellow, respectively. (b) Inhibitor RO1 superimposed on the substrate envelope: The substrate envelope is shown as a purple translucent model, while the inhibitor region embedded inside the substrate envelope and protruding atoms are shown in dark and light shades of green, respectively (also refer to the previous panel). The protruding atoms are labeled except for O-6 and C-9, which are protruding in the opposite direction. (c) Possible rationale for V32I mutation. The VDW packing interaction between Val32/32′ (illustrated as yellow surfaces) and the atoms protruding outside the P2 (O-5) and P2′ (C-21 and C-23) sites of the substrate envelope are shown. The flaps are displayed in tube representation for reference. The figures were created using Grasp (11).