 Interface comparison between nCoV-RBD and SARS-RBD with ACE2.(A) Structural alignment for the nCoV-RBD and SARS-RBD. The complex structure of ACE2 and SARS-RBD (PDB code: 2AJF) is superimposed to our cryo-EM structure. The boxed regions are illustrated in details in panels B-D. nCoV-RBD and the PD in our cryo-EM structure are coloured orange and cyan, respectively; SARS-RBD and its complexed PD are coloured green and gold, respectively. (B-D) Variation of the interface residues between nCoV-RBD (labeled brown) and SARS-RBD (labeled green). In this three panels, the two structures are superimposed relative to RBD. 