Structural Organization and Dynamic Characteristics of the Binding Site for Conformational Rearrangement Inhibitors in Hemagglutinins from H3N2 and H7N9 Influenza Viruses

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D. D. Podshivalov^1,a*, E. M. Kirilin^1,2, S. I. Konnov¹, and V. K. Švedas^1,2,b*

¹Lomonosov Moscow State University, Faculty of Bioengineering and Bioinformatics, 119991 Moscow, Russia

²Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia

^* To whom correspondence should be addressed.

Received February 4, 2020; Revised March 2, 2020; Accepted March 2, 2020

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Computer models of hemagglutinins from the H3N2 and H7N9 influenza viruses were developed to study structural organization and dynamic characteristics of the binding site for the conformational rearrangement inhibitors. The metadynamics was used to map the binding site free energy and to define the volume of its most energetically favorable states. It was demonstrated by simulation of the umifenovir (Arbidol) interaction with hemagglutinin that ligand binding requires an increase in the binding site volume and deformation of its most energetically favorable state. We also identified amino acid residues directly involved in the ligand binding that determine the binding efficiency, as well as the dynamic behavior of the binding site. The revealed features of the binding site structural organization of the influenza virus hemagglutinin should be taken into account when searching for new antiviral drugs capable to modulate its functional properties.

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KEY WORDS: hemagglutinin, influenza virus, molecular dynamics, metadynamics

DOI: 10.1134/S0006297920040100

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