The nuts and bolts of SARS-CoV-2 Spike Receptor Binding Domain heterologous expression

Maffei, M.; Montemiglio, L. C.; Vitagliano, G.; Fedele, L.; Sellathurai, S.; Bucci, F.; Compagnone, M.; Chiarini, V.; Exertier, C.; Muzi, A.; Roscilli, G.; Vallone, B.; Marra, E.

doi:10.1101/2021.09.17.460782

bioRxiv · 10.1101/2021.09.17.460782

The nuts and bolts of SARS-CoV-2 Spike Receptor Binding Domain heterologous expression

Maffei, M.·Montemiglio, L. C.·Vitagliano, G.·Fedele, L.·Sellathurai, S.·Bucci, F.·Compagnone, M.·Chiarini, V.·Exertier, C.·Muzi, A.·Roscilli, G.·Vallone, B.·Marra, E.

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Abstract

COVID-19 is a highly infectious disease caused by a newly emerged coronavirus (SARS-CoV-2) that has rapidly progressed into a pandemic. This unprecedent emergency has stressed the significance of developing effective therapeutics to fight current and future outbreaks. The receptor-binding domain (RBD) of the SARS-CoV-2 surface Spike protein is the main target for vaccines and represents a helpful "tool" to produce neutralizing antibodies or diagnostic kits. In this work, we provide a detailed characterization of the native RBD produced in three major model systems: Escherichia coli, insect and HEK-293 cells. Circular dichroism, gel filtration chromatography and thermal denaturation experiments indicated that recombinant SARS-CoV-2 RBD proteins are stable and correctly folded. In addition, their functionality and receptor-binding ability were further evaluated through ELISA, flow cytometry assays and bio-layer interferometry.

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Maffei, M., Montemiglio, L. C., Vitagliano, G., Fedele, L., Sellathurai, S., Bucci, F., Compagnone, M., Chiarini, V., Exertier, C., Muzi, A., Roscilli, G., Vallone, B., Marra, E.. 2021-09-17. The nuts and bolts of SARS-CoV-2 Spike Receptor Binding Domain heterologous expression. https://doi.org/10.1101/2021.09.17.460782

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