Crystal structure of SARS-CoV-2 spike receptor-binding domain bound with ACE2. (A) Cartoon representation. (B) Gaussian surface representation. hACE2 is in green, the core of SARS-CoV-2 RBD is in red, and the RBM is in blue. The β1-β7 typical motifs of RBD (Lan et al., 2020) are indicated in (A). The structures have been drawn from PDB 6MOJ (Lan et al., 2020) by Mol on the PDB website.