Figure 3.

Spectroscopic properties of ANA-Y. (A) Absorption spectra of the ANA-Y (0.6 μM) were measured in the absence (dashed line) or presence (solid line) of 240-μM oxygen. The absorption peak of DosH at 560 nm is indicated with an arrow. (B) Excitation (gray color) and emission (black color) spectra of ANA-Y were measured in the absence (dashed line) or presence (solid line) of 240-μM oxygen. Excitation and emission spectra of ANA-Y (1 μM) were recorded at emission and excitation wavelengths of 527 and 500 nm,respectively. Data are expressed relative to the fluorescence intensity of ANA-Y in the presence of oxygen (1.0).