Figure 2.
Dissociation kinetics of peptides with hydrogen bond-deficient variants of class II molecules. The wt or hydrogen bond-deficient class II molecules were tested for their dissociation kinetics with the indicated peptide. Shown for comparison are the dissociation kinetics displayed by wt class II molecules (× symbols) with those displayed after mutation of hydrogen-bonding amino acids. In each pair, the left graph compares the loss of His hydrogen bonds [C-terminal α-His-68 (open circles) vs. N-terminal β-His-81-H− (filled circles)], whereas the right graph compares the loss of Asn hydrogen bonds [C-terminal α-Asn-69-H− (open squares) vs. N-terminal β-Asn-82-H− (filled squares)].