Fig. 1.

Kinetic results. (A) Stopped-flow kinetic traces for reaction of 15 μM CYP119 with 0.9 mM peroxynitrite at pH 7.4 and 23°C; CYP119-II was monitored at 433 nm (solid line), native CYP119 was monitored at 417 nm (dashed line), and peroxynitrite was monitored at 302 nm (dotted line). (B) Spectra from reaction of ferric CYP119 (5 μM) with sodium nitrite (0.3 M) in 50 mM phosphate buffer (pH 7.4) at 23°C; the spectra were recorded at 1.4, 20, 30, and 100 s after mixing, and the rates of signal growth at 433 nm and decay at 417 nm are equal with a pseudo-first-order rate constant of k = 0.028 s⁻¹.