Fig. 6: Somatic hypermutations of 28-12.
a Sequence alignment of 28-12 and its UCA. Dots indicate identical residues. CDR regions according to IMGT are shown in red. b, c The reactivity of 28-12 germline variants to H3N2 (b) and H1N1 HAs (c). GHGL, VH germline paired with VL germline. HGL, 28-12 VH paired with its VL germline. GHL, 28-12 VL paired with its VH germline. d Heatmap showing the EC50 values of 28-12 variants with single somatic mutations to H3N2 and H1N1 HAs. e For both 28-12-H3 and 28-12-H1 complexes, VL R53 forms hydrogen bonds with the main chain of VH S103 in HCDR3, which also contacts the residue D46HA2 through hydrogen bonds. f For both 28-12-H3 and 28-12-H1 complexes, VL D92 of 28-12 forms salt bridges with K39HA2 of helix A. g VH F114 inserts into a hydrophobic groove formed by L38HA2 of both H3N2 and H1N1 HAs. The colors of HA1 and HA2 and the heavy chain and light chain of 28-12 are shown as in Fig. 4. The salt bridge and hydrogen bond are shown as red and black dashed lines, respectively. Data are presented as mean values of duplicates (b, c). Representative data are shown from two independent experiments (b, c).
