Extended Data Fig. 9: Local regions of mutations in BA.2S.
From: Structural and functional characteristics of the SARS-CoV-2 Omicron subvariant BA.2 spike protein
(a) A close-up view of the unique mutations in the BA.2 RBD. Superposition of the BA.2 RBD structure in ribbon representation and cyan with the structures of the RBDs of G614 S in yellow and BA.1 in gray. The mutated residues and the N-linked glycans at Asn343 are in stick model. NAG, N-acetylglucosamine. (b) Density in the BA.2 map near the short helix formed by residues 365-371 and the model fitting. (c) Possibly ordered 70-80 loop. The N-terminal segment of the BA.2S is shortened by the three-residue deletion (L24del-P25del-P26del) and also constrained by the disulfide bond between Cys15 and Cys136. There is reasonable density in which the 70-80 loop, disordered in many previous S trimer structures, could be modeled (shown in red). Such a structured loop can create a knot in this region, however, which will need a higher resolution map to confirm.
