Our research is focused on understanding and controlling the mechanisms of redox enzymes: (1) Mammalian NO synthases are large multidomain enzymes involved in the regulation of blood flow/pressure, immune response and nerve signalling. We aim to understand their mechanisms of action on the molecular level and find new ways to control their activity through inhibition or activation. (2) Heme-dependent monooxygenases are powerful catalysts, able to insert oxygen atoms specifically into otherwise unreactive molecules. We are examining the energetics of this process and remodelling the enzymes to trap reactive intermediates and to gain control over their function. (3) Using robust electron transfer proteins, we are building protein-based electron transfer wires for use in enzyme electrochemistry and in the construction of novel electroactive enzymes.

SELECTED RECENT PUBLICATIONS

1. “Thermodynamic and Kinetic Analysis of the Nitrosyl, Carbonyl and Dioxy Heme Complexes of Neuronal Nitric Oxide Synthase: the Roles of Substrate and Tetrahydrobiopterin in Oxygen Activation” Ost, T.W.B., and Daff, S.* (2005) J. Biol. Chem. 280, 965-973
2. “Redox Properties of the Isolated FMN- and FAD-binding Domains of Neuronal NO Synthase” Garnaud, P.E., Koetsier, M., Ost, T.W.B. and Daff, S.* (2004) Biochemistry 43, 11035-11044.
3. “Oxygen activation and electron transfer in Flavocytochrome P450 BM3”. Ost, T.W.B., Clark, J., Mowat, C.G., Miles, C.S., Walkinshaw, M.D., Reid, G.A., Chapman, S.K. and Daff, S.* (2003) J. Am. Chem. Soc. 125, 15010-15020.
4. “Calmodulin Activates Electron Transfer Through Neuronal NO Synthase Reductase Domain By Releasing an NADPH-Dependent Conformational Lock”. Craig, D.H., Chapman, S.K., and Daff, S.* (2002) J. Biol. Chem. 277, 33987-33994.