Figure 4

Time series of Fc-Fab2 hydrogen bonds in steered MD simulations. (a) Total number of Fab2-Fc hydrogen bonds (left axis) and distance between the Fc and Fab2 center of masses (right axis) for the first 25 ns. (b) Timeseries of the hydrogen-acceptor distance for the four long-lived hydrogen bonds showing that these bonds are completely unbound beyond 9 ns. (c) Ab conformations at 0, 7.6, and 9 ns. The boxes show the locations of the four long-lived hydrogen bonds identified in Fig. 3. The absence of the boxes in the “9 ns structure” indicates the loss of the hydrogen bonds.