Fig. 8.
Mutations in the gB Quad mutant do not affect the overall conformation of the gB ectodomain and cause only small local changes. (A) Crystal structure of the gB Quad mutant ectodomain (yellow) overlaid onto the structure of the WT gB (cyan). Only a single protomer (chain A) is shown. (B) A close-up view of the mutated region. Mutated residues are shown as sticks and labeled. (C) In gB Quad mutant, the side chain of F503 relocates to fill the void formed by R505G mutation. (D) A close-up view of the hydrogen bonds between the N-terminus of the central -helix αC in domain dIII (magenta) and domains dII and dV in the WT gB and gB Quad. Mutations eliminated all but one hydrogen bond. Residues involved in hydrogen bonds are shown as sticks and labeled. Hydrogen bonds are shown as dashed lines.