Figure 1.

HIV-1 integrase (IN) inhibitor resistance mutations superimposed on a crystal structure of the IN central core domain bound to a prototype diketo acid inhibitor (5CITEP; PDB 1QS4) [54]. IN residues 56 to 165 are displayed in gray cartoon mode to represent secondary structural properties. 5CITEP is represented using cyan spheres. Active site residues D64, D116, and D152 are in white. Sites associated with the most commonly occurring primary mutations are in red (T66, E92, G140, S147, Q148, and N155). Sites associated with the most common accessory mutations (L74, T97, E138, V151, S153, and S163) and with primary mutations that have been observed solely in vitro (F121, Q145, and P146) are in yellow. Mg⁺⁺ is a blue sphere. Residues 141 to 144, which form part of the highly mobile loop extending between G140 and G149, were not resolved in this crystal structure.