Abstract
The rise of SARS-CoV-2 variants, with changes that could be related to an increased virus pathogenicity, have received the interest of the scientific and medical community. In this study, we evaluated the changes that occurred in the viral spike of the SARS-CoV-2 Omicron variant and whether these changes modulate the interactions with the angiotensin-converting enzyme 2 (ACE2) host receptor. The mutations associated with the Omicron variant were retrieved from the GISAID and covariants.org databases, and a structural model was built using the SWISS-Model server. The interaction between the spike and the human ACE2 was evaluated using two different docking software, Zdock and Haddock. We found that the binding free energy was lower for the Omicron variant as compared to the WT spike. In addition, the Omicron spike protein showed an increased number of electrostatic interactions with ACE2 than the WT spike, especially the interactions related to charged residues. This study contributes to a better understanding of the changes in the interaction between the Omicron spike and the human host ACE2 receptor.
Highlights
The viral infection related to SARS-CoV-2 in humans is a recent evolutionary event.the occurrence of genetic mutations is increasing continuously while the virus is disseminated worldwide, allowing the identification of several viral variants that are actively circulating in the population [1]
The obtained results indicated that the mutations that occurred in the receptor-binding domain (RBD) of the Omicron variant resulted in an increased number of interactions between the spike and angiotensin-converting enzyme 2 (ACE2) receptor, especially, the number of interactions associated with the charged residues was increased (Table 2)
It has been previously described that the interactions between the charged residues of the viral spike and the host ACE2 play a major role in the complex stabilization and host selectivity [7,18,19]
Summary
The viral infection related to SARS-CoV-2 in humans is a recent evolutionary event.the occurrence of genetic mutations is increasing continuously while the virus is disseminated worldwide, allowing the identification of several viral variants that are actively circulating in the population [1]. The information gained from the analysis of the single residue mutants allowed us to hypothesize that variants carrying multiple mutations in the RBD will exhibit an even higher stabilizing effect on the interaction between the viral spike and the host ACE2 receptor [15]. The Omicron variant carries over 30 mutations in the viral spike, among which eight mutations are located directly in the receptor-binding region of the RBD [16].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
