Figure 1.
Yeast Display of RBDs from SARS-CoV-2 and Related Sarbecoviruses
(A) Maximum likelihood phylogeny of sarbecovirus RBDs. RBDs included in the present study are in bold colored text. Node labels indicate bootstrap support.
(B) RBD yeast-surface display enables fluorescent detection of RBD expression and ACE2 binding.
(C) Yeast displaying the indicated RBD were incubated with varying concentrations of human ACE2, and binding was measured via flow cytometry. Binding constants are reported as KD,app from the illustrated titration curve fits.
(D) Comparison of yeast-display binding with previous measurements of the capacity of viral particles to enter ACE2-expressing cells. Relative binding is Δlog10(KD,app) measured in the current study; relative cellular entry is infection of ACE2-expressing cells by vesicular stomatitis virus (VSV) pseudotyped with spike containing the indicated RBD, reported by Letko et al. (2020) in arbitrary luciferase units relative to SARS-CoV-1 RBD; n.d., not determined.