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In this thesis, Xiaoshi Wang investigates the function and mechanism of a newly discovered heme-thiolate peroxygenase, AaeAPO. This enzyme class comes from Agrocybe aegerita and is used in the conversion of inert hydrocarbons to alcohols. Xiaoshi's work focuses on an extracellular P450 enzyme which is not limited in its stability and lack of solubility and therefore is relevant for widespread industrial use. The author demonstrates that the peroxygenase catalyzes a wide range of reactions. In some cases the author even describes very difficult transformations in molecules that are highly inert. Her detailed investigations provide a mechanistic framework for how the peroxygenase catalyzes such a large number of reactions. A major highlight of this thesis is the identification of key short-lived intermediates in the catalytic cycle of the peroxygenase, using rapid kinetic and spectroscopic methods, as well as the elucidation of the thermodynamic properties of these high-energy intermediates. This work adds new insight into an important class of enzymes.

There are many mononuclear iron containing enzymes in nature that utilize molecular oxygen and transfer one or both oxygen atoms of O2 to substrates. These enzymes catalyze many processes including the biosynthesis of hormones, the metabolism of drugs, DNA and RNA base repair and, the biosynthesis of antibiotics. Therefore, mononuclear iron containing enzymes are important intermediates in bioprocesses and have great potential in the commercial biosynthesis of specific products since they often catalyze reactions regioselectively or stereospecifically. Understanding their mechanism and function is important and will assist in searches for commercial exploitation. In recent years, advances in experimental as well as theoretical methodologies have made it possible to study the mechanism and function of these enzymes and much information on their properties has been gained. This book highlighting recent developments in the field is, therefore, a timely addition to the literature and will interest a broad readership in the fields of biochemistry, inorganic chemistry and computational chemistry. The Editors, leaders in the field of nonheme and heme iron containing monoxygenases, have filled the book with topical review chapters by leaders in the various sub-disciplines.

For this second edition of their much praised Cytochrome P450, the editors have collected accounts of the essential core techniques that use the latest methodologies for the investigation of P450s. Highlights include protocols for spectral analysis and purification of P450s, enzymatic assays of P450s and flavin-containing monooxygenases (FMOs), expression of P450s and FMOs in heterologous systems, and the production and use of antipeptide antibodies. Additional chapters contain readily reproducible techniques for the transfection of hepatocytes for gene regulation studies, P450 reporter gene assays, in situ hybridization, and analysis of genetic polymorphisms. Also described are techniques for the generation of mice with targeted gene disruptions. Although the emphasis is on P450s of mammalian origin, many of the readily reproducible methods described are suitable for P450s from any source. Each chapter is written by researchers who have been involved in the development and application of the particular technique to P450s or FMOs. The protocols are presented in a step-by-step manner, with extensive cross-references to notes that highlight critical steps, potential problems, and alternative methods so that the researcher can understand the basis of the method and perform it successfully. Cutting-edge and highly practical, Cytochrome P450, Second Edition provides both novices and experienced researchers across many fields all the tools needed today to elucidate the crucial biological role played by cytochrome P450 in the metabolism of therapeutic drugs, chemical carcinogens, and environmental pollutants.