Skip to main content
. 2021 Oct 28;13(11):2177. doi: 10.3390/v13112177

Figure 8.

Figure 8

Figure showing the intralineage variability of the main neutralising epitope in the NTD: the case of India variants. (A) Delta/B.1.617.2 variant. (B) Delta/AY.37 variant. The left panels in (A) and (B) show the positions of residues K147 and R246 that face the antibody. The superposition of the secondary structure shows that the conformational changes between these variants chiefly involve the amino acid side chain orientation. In the case of Delta/B.1.617.2, both K147 and R246 interact with the antibody, whereas in the case of Delta/AY.37, R246 moves away from the antibody, while K147 gets closer, resulting in decreased binding to avoid steric clash. The middle panels show the NTD surface as “seen” by the antibody. The right panels show the subtle rearrangements of the NTD structure of both India variants. The main change concerns the orientation of K147.