Structural Basis for Interactions between Influenza A Virus M2 Proton Channel and Adamantane-Based Antiviral Drugs

Abstract

Influenza A virus pandemics still remain a threat to global health. One class of antiviral drugs, namely, inhibitors of the specific viral enzyme neuraminidase, is predominantly used in the fight against these pandemics. These antivirals include zanamivir (Relenza™) and oseltamivir (Tamiflu™). The viral resistance to this class of compounds steadily increases. The M2 proton channel of influenza A virus is an alternative clinically proven target for antiviral therapy. However, many circulating virus strains bear amino acid mutations in the M2 protein, causing resistance to drugs of the adamantane series, M2 blockers, such as rimantadine and amantadine. Consequently, inhibitors targeting mutants of the M2 channel are urgently needed for public biosafety and health. This review is devoted to structural-functional interactions used in practice and mediated by the action of experimental drugs on the protein target, the transmembrane domain of the influenza virus M2 proton channel. An analysis of the experimental and model structural data available in open access is presented.