IPNS-ACV-NO Complex

Nitric oxide reacts with the ferrous site of many mononuclear non-heme iron enzymes to form a stable, reversible analog of possible iron-oxygen intermediates in catalyis. Through spectroscopic methods and Density Functional Theory studies of model complexes, the electronic structure of the {FeNO}⁷ unit has been well defined for a set of redox innocent ligands.

During catalysis, α-ketoglutarate (αKG)-dependent enzymes bind the αKG co-factor and subsequent decarboxylation of this co-factor supplies two electrons to the active site. Other αKG-related enzymes including Isopenicillin N-synthase (IPNS) bind other redox active substrates that contribute to reactivity. My project uses spectroscopic methods and Density Functional Theory studies to define the electronic structures of these enzyme-substrate-NO complexes. By contrasting the electronic structures of these complexes to that of previously studied model complexes, we can elucidate the contributions of the redox active substrates to the reaction pathways of these enzymes.