Figure 3. Screening of the SARS-CoV-2 potential variants (PVs) for binding to Fc-ACE2 using yeast display.
(A) The RBDs of the PVs were expressed on the surface of Saccharomyces cerevisiae cells as genetic fusions to the AGA2 surface protein. An anti-Myc antibody (Ab) and an anti-human secondary Ab labeled with different fluorophores were subsequently used to label the RBD-expressing cells and the cells bound to Fc-ACE2, respectively. (B) Saccharomyces cerevisiae cells displaying the indicated RBD PV were incubated with 40 nM Fc-ACE2. Binding to Fc-ACE2 was detected with an Alexa647-conjugated anti-human secondary Ab. The RBD variants highlighted with red arrows were chosen for further experimental characterization.
