FIG 1.

The glycan epitope of PGT135 encompasses the Asn332, Asn392, and Asn386 sites. (A) A previously reported crystal structure reveals the interaction of a PGT135 Fab domain with the Asn332 (Man₆GlcNAc₂), Asn392 (Man₈GlcNAc₂), and Asn386 (Man₁GlcNAc₂) glycans from a gp120_JR-FL core (15). The protein moiety is depicted in a ribbon diagram, and glycans are depicted as sticks. Mannose (Man) residues are colored in green, and N-acetlyglucosamine (GlcNAc) residues are colored in blue. (B) Enlarged view of the PGT135 glycan epitope. (C) Schematic representation of a Man₉GlcNAc₂ glycan, with the D1 to D3 arms annotated and the glycans resolvable in the crystal structure. Glycan structures are shown according to the proposed method of Harvey et al. (40), with residues colored according to panels A and B. Images were made in PyMol using PDB code 4JM2.