FIGURE 4.

HDX of β-strand B2. A, HDX plot of peptide 298–305 from strand B2. B, localized difference in deuterium uptake for individual residues (red bars) or segments (orange bar) of peptide 298–305 from unbound versus TF-bound FVIIa after 4 h exchange time. C, structural representation of the B2 strand with individual sites revealed by ETD to undergo reduced HDX upon TF binding highlighted (PDB ID: 1DAN). Based on HDX-ETD data in B, H-bonds involving amide hydrogens from residues Leu-300, Val-302, Arg-304, and Leu-305 that are destabilized or absent in unbound FVIIa are shown in lime.