1. Academic Validation
  2. Unraveling the Binding, Proton Blockage, and Inhibition of Influenza M2 WT and S31N by Rimantadine Variants

Unraveling the Binding, Proton Blockage, and Inhibition of Influenza M2 WT and S31N by Rimantadine Variants

  • ACS Med Chem Lett. 2018 Jan 29;9(3):198-203. doi: 10.1021/acsmedchemlett.7b00458.
Antonios Drakopoulos 1 Christina Tzitzoglaki 1 Kelly McGuire 2 Anja Hoffmann 3 Athina Konstantinidi 1 Dimitrios Kolokouris 1 Chunlong Ma 4 Kathrin Freudenberger 5 Johanna Hutterer 5 Günter Gauglitz 5 Jun Wang 4 Michaela Schmidtke 3 David D Busath 2 Antonios Kolocouris 1
Affiliations

Affiliations

  • 1 Department of Pharmaceutical Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou 15771, Greece.
  • 2 Department of Physiology and Developmental Biology, Brigham Young University, Provo, Utah 84602, United States.
  • 3 Department of Medicinal Microbiology, Section Experimental Virology, Jena University Hospital, Hans Knoell Str. 2, D-07745 Jena, Germany.
  • 4 Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States.
  • 5 Institut für Physikalische und Theoretische Chemie, Eberhard-Karls-Universität Tübingen, 72074 Tübingen, Germany.
Abstract

Recently, the binding kinetics of a ligand-target interaction, such as the residence time of a small molecule on its protein target, are seen as increasingly important for drug efficacy. Here, we investigate these concepts to explain binding and proton blockage of rimantadine variants bearing progressively larger alkyl groups to influenza A virus M2 wild type (WT) and M2 S31N protein proton channel. We showed that resistance of M2 S31N to rimantadine analogues compared to M2 WT resulted from their higher koff rates compared to the kon rates according to electrophysiology (EP) measurements. This is due to the fact that, in M2 S31N, the loss of the V27 pocket for the adamantyl cage resulted in low residence time inside the M2 pore. Both rimantadine enantiomers have similar channel blockage and binding kon and koff against M2 WT. To compare the potency between the rimantadine variants against M2, we applied approaches using different mimicry of M2, i.e., isothermal titration calorimetry and molecular dynamics simulation, EP, and Antiviral assays. It was also shown that a small change in an amino acid at site 28 of M2 WT, which does not line the pore, seriously affects M2 WT blockage kinetics.

Figures