Figure 4.

Kinetics of H/D exchange of (A) WALP16 and (B) WALP16(+10). On the y-axis, the natural logarithm of the amount of protected hydrogens in the peptide [ln(H)] is shown. The time envelopes from 2–100 min for both peptides are indicated. From the slopes of the curves in the plot, the half-lives of specific hydrogen populations in this time period were calculated, and from the intercepts with the y-axis, the number of hydrogens involved. For WALP16, the intermediate exchange data are represented by the lines (1) y = −4.9x 10⁻²x + 2.81 (r = 0.95), and (2) y = −2.9x 10⁻³x + 2.66 (r = 0.99); for the intermediate exchange of WALP16(+10) (1) y = −3.7 × 10⁻²x + 2.81 (r = 0.97), (2) y = −9.9 × 10⁻³x + 2.68 (r = 0.99), and (3) y = −2.0 × 10⁻³x + 2.49 (r = 0.99).