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This book contains five chapters exploring the structure and function of cytochromes, which are redox-active proteins that contain a heme with a central Fe atom at its core as a cofactor. Chapter One explores the functional relevance of cytochrome c-oxidase subunit IV isoform expression for cellular energy sensing, ATP production, and oxidative stress levels and its role in neurodegeneration. Chapter Two deals with the factors determining the orientation of ligated histadines in hemoproteins, cytochromes, and model systems. Chapters Three and Four include comparative studies of native and synthetic cytochrome b. Lastly, Chapter Five discusses some examples of synthetic and native cytochromes used as central components of biosensors in bioelectronic/biocatalytic applications.

This brief introduces the structural and functional characterization of this important group of proteins. The content of each chapter is aimed at the non-specialist so that key concepts, methodologies and applications can be presented in a'snapshot'style volume. Multiheme cytochromes are ever more important now that it is possible to obtain genome sequences of microorganisms which have major biotechnological and environmental implications. There is a tremendous profusion of multiheme cytochromes which have great potential as targets for bioremediation and bioenergy applications. This brief gives a glimpse of an intriguing and fast-moving field.

An Introduction that describes the origin of cytochrome notation also connects to the history of the field, focusing on research in England in the pre-World War II era. The start of the modern era of studies on structure-function of cytochromes and energy-transducing membrane proteins was marked by the 1988 Nobel Prize in Chemistry, given to J. Deisenhofer, H. Michel, and R. Huber for determination of the crystal structure of the bacterial photosynthetic reaction center. An ab initio logic of presentation in the book discusses the evolution of cytochromes and hemes, followed by theoretical perspectives on electron transfer in proteins and specifically in cytochromes. There is an extensive description of the molecular structures of cytochromes and cytochrome complexes from eukaryotic and prokaryotic sources, bacterial, plant and animal. The presentation of atomic structure information has a major role in these discussions, and makes an important contribution to the broad field of membrane protein structure-function.

This book will describe the nuclear encoded genes and their expressed proteins of mitochondrial oxidative phosphorylation. Most of these genes occur in eukaryotic cells, but not in bacteria or archaea. The main function of mitochondria, the synthesis of ATP, is performed at subunits of proton pumps (complexes I, III, IV and V), which are encoded on mitochondrial DNA. The nuclear encoded subunits have mostly a regulatory function. However, the specific physiological functions of the nuclear encoded subunits of complexes I, III, IV, and V are mostly unknown. New data indicates that they are essential for life of higher organisms, which is characterized by an adult life without cell division (postmeiotic stage) in most tissues, after the juvenile growth. For complex IV (cytochrome c oxidase) some of these subunits occur in tissue-specific (subunits IV, VIa, VIb, VIIa, VIII), developmental-specific (subunits IV, VIa, and VIIa) as well as species-specific isoforms. Defective genes of some subunits were shown to induce mitochondrial diseases. Mitochondrial genes and human diseases will also be covered.

The Mammalian Mitochondrial Respiratory Chain provides the vocabulary related to the mitochondrial respiratory chain in mammalian species. It explores the heterogeneous nature of mitochondria, the mammalian mitochondrial cytochromes, the concept of a respiratory chain for the oxidation of substrates, the cytochrome and non-cytochrome components of the chain, and the role of the respiratory chain in energy conservation. Organized into five chapters, this volume begins with an overview of the structure and composition of mitochondria in heart, liver, kidney, and brain before turning to the NADH oxidase system and its ability to generate one additional high-energy bond for every pair of electrons transferred compared to the succinate oxidase system. It also describes electron transfer in the respiratory chain and inhibitors of the respiratory chain such as antimycin A, along with differences in the pathways of electrons from succinate, choline, and NADH to oxygen as well as systems mediated by electron-transferring flavoprotein. The reader is also introduced to the processes involved in the fragmentation, extraction, and recombination of mitochondria; artificial electron acceptors such as phenazine methosulfate and artificial electron donors such as ascorbate and tetramethyl-p-phenylenediamine; and the role of flavoproteins, including flavin mononucleotide and flavin adenine dinucleotide, in electron transport. The book concludes with a chapter that explains how the oxidation-reductions of the respiratory chain release energy in discrete packets. Graduate students and beginning researchers in biology will find this book extremely helpful.