Figure 7.

Analysis of the accessibility of the epitope on all three individual E protein molecules in an asymmetric unit.

A Superposition of the three individual E protein molecules in an asymmetric unit (molecules A–C). The epitope location is indicated by a rectangular box. Molecules A, B and C in each asymmetric unit are colored in yellow, red and gray, respectively. The E proteins have similar conformation indicating that the lack of Fab binding to molecule C is mainly due to the blockage of the epitope by a neighboring E protein molecule.

B–D Molecules A, B, and C in each asymmetric unit are colored in yellow, red and gray, respectively. The epitope is colored in the same coloring scheme as in Fig 4B. The epitopes on molecules A (B) and B (C) (circled) are fully accessible. (D) In contrast, the part of the epitope on molecule C is blocked by DIII of a neighboring E protein (indicated by arrow). For clarity, one of the E proteins (left) is represented as a transparent surface to show the hidden part of an adjacent epitope (marked by*).