Calmodulin enables electrons to pass to the iron atom, and also greatly speeds the introduction of electrons into the enzyme s flavin groups. We are studying three aspects of NOS regarding cell biology. One project seeks to understand how NOS interactions with other cellular proteins such as caveolins or kalirin modulate the assembly and activity of the NOS enzymes at a molecular level. A third project is investigating gene expression changes in response to NO synthesis under different cellular conditions, keying on enzymes involved in iron uptake, storage, and homeostasis. Structure of NO synthase oxygenase dimer with pterin and substrate.
Electron transfer occurs between flavin and heme groups located on adjacent subunits in the dimer.
Sennequier, N., and D. J. Stuehr. Antifungal imidazoles block assembly of inducible NO synthase into an active dimer. Huang, L., H. M. Abu-Soud, R. Hille, and D. J. Stuehr. Characterization and roles for tetrahydrobiopterin and substrate in protecting against or reversing the P420 conversion. Biochemistry 38, 1912-1920.