Dicks, Justin Kyle. Molecular Oxygen Triggered Biocatalytic C-C Bond Formation: Probing Olefination Mechanism Catalyzed by a 2-Oxo-glutarate Dependent Non-Heme Enzyme: AsqJ. (Under the direction of Wei-chen Chang). 2-Oxo-glutarate dependent non-heme iron(II) enzymes are a large and complex family

Dicks, Justin Kyle. Molecular Oxygen Triggered Biocatalytic C-C Bond Formation: Probing Olefination Mechanism Catalyzed by a 2-Oxo-glutarate Dependent Non-Heme Enzyme: AsqJ. (Under the direction of Wei-chen Chang). 2-Oxo-glutarate dependent non-heme iron(II) enzymes are a large and complex family of enzymes capable of catalyzing a gamut of reactions. These enzymes are present in a number of life forms from humans and animals to bacteria and fungi. The enzyme family is interesting because of its ability to incorporate inert molecular oxygen into its reaction mechanism. While each enzyme mechanism will slightly differ based on the function, each biocatalyzed reaction is driven by the formation of a high-spin iron(IV) center within the enzyme active site. This iron(IV) center is what makes 2-oxo-glutarate-dependent enzymes capable of catalyzing an array of reactions like halogenation, hydroxylation, desaturation, epoxidation, etc. While each enzyme has subtle differences in reaction, they are all share a common mechanism in the formation of the iron (IV) core. Aspergillus nidulans (A. nidulans) is a fungus that is capable of producing viridicatin, a key 6,6-quinolone structural core found in a number of biologically active small molecules. Previous studies have revealed that AsqJ is a key enzyme involved in the formation of viridicatin. This particular 2-oxoglutarate-dependent enzyme is fascinating, due to its cascade mechanism that incorporates a desaturation, and an epoxidation that leads to the final product. Due to its relation to the 2-oxoglutarate-dependent enzyme family, AsqJ is thought to integrate the iron(IV) center into its mechanism. Previous studies have proposed an explanation to the desaturation of cyclopeptin, but remain experimentally untested. Herein describes the process to define olefination pathway of cyclopeptin to dehydro-cyclopeptin via AsqJ biocatalysis through implementation of mechanistic probes. © Copyright 2017 by Justin Kyle Dicks All rights Reserved Molecular Oxygen Triggered Biocatalytic C-C Bond Formation: Probing Olefination Mechanism Catalyzed by a 2-Oxo-glutarate Dependent Non-Heme Enzyme: AsqJ By Justin Kyle Dicks A thesis submitted to the Graduate Faculty of North Carolina State University In partial fulfillment of the requirements for the Degree of Master of Science.