Figure 3. Footprints of ZIKV-117 Fabs on the E protein.

The figure shows a roadmap of the ZIKV E protein. The E protein residues are coloured according to their distance from the virus centre, with the residues closer to the centre coloured blue (218 Å) and those farthest from the centre coloured red (235 Å). The colours of residues transition from blue to red through green. The position of the icosahedral two-fold axis is marked with a blue oval. The quasi two-fold axes are marked as orange or yellow ovals. The outlines of the individual E protein chains are marked with thick black lines, and the chains are labelled as per the convention described in Fig. 2. The residues Asp67, Gln89 and Lys118 within the ZIKV-117 epitope are highlighted with red lines. The ZIKV-117 footprints formed by E protein residues that lie within 8 Å of the bound Fab at the 2f (yellow outline) and 3f (white outline) sites are highlighted across the quasi two-fold axis (orange oval). The footprints extend across multiple E proteins, and there is significant overlap between the footprints. At the 5f site, DIII of chain A′′ (highlighted with a white arrow) poses a steric barrier to the binding of Fab.