Fig 2. Analysis of 10E8 somatic hypermutation identifies critical K52T mutation.

(A) Summary of CDR H2 somatic hypermutation and 10E8 neutralization. Total mutations from germline are indicated for both heavy and light chains. The CDR H2 germline sequence is shown colored blue with somatic mutations indicated in black. Viruses neutralized with an IC₅₀ < 50 μg/ml or < 1 μg/ml are indicated (see S1 Table for details on HIV-1 isolate panel). (B) Superposition of mature 10E8 complex structure and 10E8 gHv/gLv. Coloring is the same as in Fig 1. (C) Expanded view of CDR H2. Residues that were mutated and gave improved 10E8 gHv/gLv neutralization levels are shown in stick representation. Residues Phe 673 (MPER) and Lys 52 (10E8 gHv/gLv) overlap and are not compatible with binding due to steric clashing.