Design of Broad-Spectrum Inhibitors of Influenza A Virus M2 Proton Channels: A Molecular Modeling Approach

Background: The influenza A virus M2 proton channel plays a critical role in its life cycle. However, known M2 inhibitors have lost their clinical efficacy due to the spread of resistant mutant channels. Thus, the search for broad-spectrum M2 channel inhibitors is of great importance. Objective: The goal of the present work was to develop a general approach supporting the design of ligands interacting with multiple labile targets and to propose on its basis the potential broad-spectrum inhibitors of the M2 proton channel. Method: The dynamic dimer-of-dimers structures of the three primary M2 target variants, wild-type, S31N and V27A, were modeled by molecular dynamics and thoroughly analyzed in order to define the inhibitor binding sites. The potential inhibitor structures were identified by molecular docking and their binding was verified by molecular dynamics simulation. Results: The binding sites of the M2 proton channel inhibitors were analyzed, a number of potential broad-spectrum inhibitors were identified and the binding modes and probable mechanisms of action of one promising compound were clarified. Conclusion: Using the molecular dynamics and molecular docking techniques, we have refined the dynamic dimer-ofdimers structures of the WT, S31N and V27A variants of the M2 proton channel of the influenza A virus, analyzed the inhibitor binding sites, identified a number of potential broad-spectrum inhibitor structures targeting them, and clarified the binding modes and probable mechanisms of action of one promising compound. The proposed approach is also suitable for the design of ligands interacting with other multiple labile targets.