Binding of SARS-CoV-2 to Cell Receptors: A Tale of Molecular Evolution

The magnified infectious power of the SARS-CoV-2 virus compared to its precursor SARS-CoV is intimately linked to an enhanced ability in the mutated virus to find available hydrogen-bond sites in the host cells. This characteristic is acquired during virus evolution because of the selective pressure exerted at the molecular level. We pinpoint the specific residue (in the virus) to residue (in the cell) contacts during the initial recognition and binding and show that the virus...cell interaction is mainly due to an extensive network of hydrogen bonds and to a large surface of noncovalent interactions. In addition to the formal quantum characterization of bonding interactions, computation of absorption spectra for the specific virus...cell interacting residues yields significant shifts of Delta lambda(max)=47 and 66 nm in the wavelength for maximum absorption in the complex with respect to the isolated host and virus, respectively.

Automated summary

The increased infectious power of SARS-CoV-2 compared to its precursor SARS-CoV is closely related to the enhanced ability of the mutated virus to locate available hydrogen-bond sites in host cells, acquired through evolutionary processes under selective pressures. The interaction between the virus and cell is mainly due to an extensive network of hydrogen bonds and noncovalent interactions.