Tabriz University of Medical Sciences Advanced Pharmaceutical Bulletin 2228-5881 11 4 2021 09 19 Studying the Effect of Amino Acid Substitutions in the M2 Ion Channel of the Influenza Virus on the Antiviral Activity of the Aminoadamantane Derivative In Vitro and In Silico 700 711 10.34172/apb.2021.079 EN Timur Mansurovich Garaev https://orcid.org/0000-0002-3651-5730 Artyom Irorevich Odnovorov https://orcid.org/0000-0001-9355-2522 Alexander Aleksandrovich Lashkov https://orcid.org/0000-0002-4295-0069 Tatiana Vladimirovna Grebennikova https://orcid.org/0000-0002-6141-9361 Marina Pavlovna Finogenova https://orcid.org/0000-0002-3611-3897 Galina Kadymovna Sadykova https://orcid.org/0000-0002-2729-6767 Alexei Gennadievich Prilipov https://orcid.org/0000-0001-8755-1419 Tatiana Anatol'evna Timofeeva Sergey Vadimovich Rubinsky Svetlana Nikolaevna Norkina Marina Mikhailovna Zhuravleva Journal Article 10.34172/apb.2021.079 2020 03 05 2020 07 15 Purpose: The aminoadamantane derivative of L-histidyl-1-adamantayl ethylamine hydrochloride (HCl*H-His-Rim) has showed a high inhibition level against influenza A virus strains in vitro. The aim of this work is to search and establish evidence of the direct effect of the drug on influenza A virus proton channel M2. Methods: The compound HCl*H-His-Rim was obtained by classical peptide synthesis methods. Influenza A virus mutants of A/PuertoRico/8/34(H1N1) strain were obtained by reverse genetics methods. The mutant samples of the virus were cultured on chicken embryos with a virus titer in the hemagglutination test. ELISA was carried out on Madin-Darby canine kidney (MDCK) monolayer cells when multiplying the virus 10-4-10-6. The binding stability of HCl*H-His-Rim was compared to those of M2 (S31N) and M2 (S31N_A30T) channels by molecular dynamic (MD) modeling. The calculation was performed taking into account the interaction with the model lipid bilayer (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) in the presence of water molecules in accordance with the three-center model. Results: It was found that HCl*H-His-Rim is a direct action drug against influenza A. The most likely conformation of drug binding to target protein has been shown. It has been found that the A30T mutation reduces the binding energy of the drug, and the results obtained in vitro have confirmed the data calculated in silico. Conclusion: The mechanism of action of HCl*H-His-Rim is directly related to the suppression of the function of the proton channel M2 of influenza A virus.