Fig. 8.

Structural constraints of PGT151 binding to B41 SOSIP.664. A PGT151 (PDB 5FUU; in complex with JRFL Env [65]) aligned to a cryo-EM structure of B41 SOSIP.664 (PDB 6U59 [33]). The fusion peptide is depicted in red and derived from the PGT151 + JRFL SOSIP.664 [41] model for reference. B PGT151 contact residues in the epitope (as defined by < 4 Å distance from paratope atoms in the PGT151 + JRFL SOSIP.664 model) and equivalent positions in BG505 and B41 SOSIP.664 reveal high conservation. Amino acids different between B41 and BG505 are highlighted in light blue. C Alignment of PGT151 Fab from the PGT151 + JRFL SOSIP.664 structure onto the b12-bound (top, PDB 5VN8 [27]) or 8ANC195- and sCD4-bound (bottom, PDB 6EDU [29]) conformation using one of three reference chains [27, 29]. Note that for clarity, the b12, 8ANC195, and sCD4 structures have been removed from the reference model. Steric clashes are depicted with translucent buff-colored stars. The clashing gp120 subunit is depicted in transparent blue. For the rest, antibody and Env colors follow those in panel A