Figure 3. Comparison of haem modes in the low-frequency region of the FeIII–NO complexes of saNOS and bsNOS.

The spectra were obtained in the presence of 1 mM L-arginine (a, which is the same spectrum as Figure 2, line c), 1 mM THF (b), H₄B (c) and in the absence of both substrate and H₄B for bsNOS (d, which is the same spectrum as Figure 2, line j) and saNOS (e, which is the same spectrum as Figure 2, line a). * represents a laser line.