Fig. 4.

Autoxidation of Ngb mutants. The plots show selected spectra during the course of the autoxidation reaction for each mutant. As changes for Ngb F28H/F42Y in the Q-band were very small, the Soret band is shown instead. The insets show the fitting of the decay to a single exponential equation. The initial spectrum is denoted by a thick black line, and the final spectrum is denoted by a thick red line Arrows indicate the direction of the spectral change.