Lipid-Mediated Effect of Glycyrrhizin on the Properties of the Transmembrane Domain of the E-Protein of the Sars-Cov-2 Virus

The interaction of glycyrrhizin with the transmembrane domain of the E-protein of the SARS-CoV-2 virus (E-protein Trans-Membrane domain, ETM) in a homogeneous aqueous solution and in a model lipid membrane is studied using the selective nuclear Overhauser effect (selective NOESY) and NMR relaxation methods. The selective NOESY shows the presence of the interaction of glycyrrhizin with ETM in an aqueous solution, which is consistent with the published modeling data, which indicate the possibility of penetration of the glycyrrhizin molecule into the channel formed by the ETM molecules. However, this conclusion is not confirmed by the NOESY experiments in the model lipid membranes—bicelles. At the same time, the NMR relaxation method reveals the effect of glycyrrhizin on the mobility of both lipids and ETM molecules in bicelles. This suggests that GA affects the activity of the coronavirus E-protein indirectly through lipids.