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bioRxiv · 10.1101/2020.09.12.294504

S494 O-glycosylation site on the SARS-COV-2 RBD Affects the Virus Affinity to ACE2 and its Infectivity; A Molecular Dynamics Study

Rahnama, S.·Azimzadeh Irani, M.·Amininasab, M.·Ejtehadi, R.
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Abstract

SARS-COV-2 is a strain of Coronavirus family which caused the extensive pandemic of COVID-19, which is still going on. Several studies showed that the glycosylation of virus spike (S) protein and the Angiotensin-Converting Enzyme 2 (ACE2) receptor on the host cell is critical for the virus infectivity. Molecular Dynamics (MD) simulations were used to explore the role of a novel mutated O-glycosylation site (D494S) on the Receptor Binding Domain (RBD) of S protein. This site was suggested as a key mediator of virus-host interaction. We showed that the decoration of S494 with elongated O-glycans results in stabilized interactions on the direct RBD-ACE2 interface with more favorable binding free energies for longer oligosaccharides. Hence, this crucial factor must be taken into account for any further inhibitory approaches towards RBD-ACE2 interaction.

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Rahnama, S., Azimzadeh Irani, M., Amininasab, M., Ejtehadi, R.. 2020-09-12. S494 O-glycosylation site on the SARS-COV-2 RBD Affects the Virus Affinity to ACE2 and its Infectivity; A Molecular Dynamics Study. https://doi.org/10.1101/2020.09.12.294504

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