An accurate eukaryotic plasma membrane assay for coronavirus binding

This project focuses on the development of a surface based ACE2 membrane sensor that will provide a highly realistic model of coronavirus cell surface binding and be amenable to high throughput screening. SARS-CoV-2 enters mammalian cells by a transduction pathway whose first stage is the interaction of its spike (S) protein on the viral surface with ACE2 (angiotensin converting enzyme-2), a type-1 transmembrane protein. Once the virus attaches to the membrane surface the S protein is modified by a cell surface protease (TMPRSS2) to form a fusion peptide which inserts into the membrane and facilitates viral transduction. Current S protein/ACE2 interaction studies have primarily focused on utilising a recombinant soluble construct of ACE2 and thus do not truly represent the in vivo processes occurring. Using our expertise with surface based supported bilayers we will fabricate an accurate membrane mimetic of the eukaryotic membrane containing full length ACE2 on a sensor surface. Neutron Reflectometry together with quartz crystal microbalance (QCM) will be used to validate the surface assemblage and viral component binding. The system will then be further developed to include other components known to be involved in ACE2/Coronavirus interaction (e.g. TMPRSS2 & B0AT1), to provide a realistic model of coronavirus membrane surface interaction. This system will be directly translatable to techniques amenable to high throughput screening (QCM and surface plasmon resonance). This will aid the scientific community in studying coronavirus membrane binding and can be used as a diagnostic tool for the identification of inhibitors of coronavirus-membrane interactions.