Figure 3.

Crystal structure of the BDBV NP^Ct–MJ20 complex. (a) Ribbon representation of the complex, with NP colored green and the MJ20 light chain and heavy chain colored cyan and blue, respectively. CDR3^HC, which forms the majority of contacts with the antigen, is shown as yellow sticks. The variable domain (V) and the constant domain (C) as well as the four complementarity-defining regions (CDRs) are marked. (b) The secondary structure of the CDR3^HC loop is shown as sticks with the main chain colored green and the side chains in yellow. The conformation of each residue is indicated in superscript. The CDR3^HC loop adopts a β-hairpin stabilized by backbone–backbone/side-chain hydrogen bonds (marked as dashed lines with their lengths in Å). Two NP^Ct residues (Tyr652 and Ser679) that form five intermolecular hydrogen bonds to CDR3^HC are shown as magenta sticks.