Mechanism of interaction of novel indolylarylsulfone derivatives with K103N and Y181I mutant HIV-1 reverse transcriptase in complex with its substrates.

BACKGROUND Novel indolylarylsulfones (IASs), designed through rational structure-based molecular modelling and docking approaches, have been recently characterized as effective inhibitors of the wild-type and drug-resistant mutant HIV-1 reverse transcriptase (RT). METHODS Here, we studied the interaction of selected halo- and nitro-substituted IAS derivatives, with the RT enzyme carrying the single resistance mutations K103N and Y181I through steady-state kinetic experiments. RESULTS The studied compounds exhibited high selectivity to the mutant RT in complex with its substrates, behaving as uncompetitive inhibitors. The presence of the K103N mutation, and to a lesser extent the Y181I, stabilized the drug interactions with the viral RT, when both its substrates were bound. CONCLUSIONS The characterization of these mutation-specific effects on inhibitor binding might be relevant to the design of more effective new generation non-nucleoside reverse transcriptase inhibitors, with better resilience towards drug resistant mutants.