Fig. 3.

Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) spike protein showing subunits and domains as well as local sequence alignments with other Betacoronaviruses. a Spike domains: N-terminal domain (NTD), receptor binding domain (RBD), receptor binding motif (RBM), fusion peptide (FP), hetapad repeat 1 (HR1), central helix (CH), connector domain (CD), transmembrane domain (TM), multibasic furin cleavage site (FCS) indicated by black box. The S1↓S2 and S2′ cleavage sites are indicated by arrows. Green boxes indicate location of N-glycosylated residues proximal to FCS. b MultAlin alignments using SARS-CoV-2 spike protein sequence numbering reference (Corpet 1988) (http://www.sacs.ucsf.edu/cgi-bin/multalin.py). Definition and accession numbers as follows: SARS2: SARS-CoV-2 Wuhan-Hu-1 (QOH25833.1); RaTG13 (QHR63300.2); ZXC21: bat-SL-CoVZXC21 (AVP78042.1); ZC45: bat-SL-CoVZC45 (AVP78031.1); HKU3: Bat SARS coronavirus HKU3 (QND76034.1); Rp3: Rp3/2004 (AAZ67052.1); GZ02: SARS coronavirus GZ02 (AAS00003.1); RmYN02: Bat coronavirus RmYN02 (QPD89843.1). SARS-CoV-2 referenced sequence indexes are shown