FIG. 7.

Stereo view of aligned A (red) and B/C (green) subunit Cα backbones with contact residues (yellow) within a penton mapped onto a single A subunit. The three major contact loops (βB-βC, βH-βI, and βD-βE) have nearly identical structures in the quasiequivalent subunits (see also Fig. 4). Some contact with the βF-βG loop, which bends away from the fivefold axis in the A subunit, may occur, but this loop only contributes ∼3% of the total virus-Fab contact area and therefore may not represent an actual contact in the real virus-antibody complex.