FIG 4.

Locations of L74 and V75 near the IN active site. The structures of the HIV-1 IN active site (A, gray [PDB ID no. 5U1C]) and the PFV IN active site (B, yellow [PDB ID no. 3S3M]) in complex with DTG (cyan sticks) are shown. Both panels are shown in cross-eyed stereo view with divalent metal ions shown in blue and viral DNA strands in orange. Panel A contains only one Mg²⁺ ion, as the structure was solved using HIV-1 IN with an E152Q active site mutation. Residue numbers in parentheses in panel B represent equivalent residue numbers in HIV-1 IN. Figures were created using PyMOL.