Molecular Mechanisms Of Oxygen Activation

Molecular Mechanisms of Oxygen Activation reviews some of the major advances that have been made in our understanding of the molecular mechanisms underlying oxygen activation, with emphasis on the role of oxygen activation in contemporary biological processes. The biological role of oxygenases in the metabolism of fatty acids and steroids is discussed, along with the functions of heme-containing dioxygenases, a-ketoglutarate-coupled dioxygenases, and pterin-requiring aromatic amino acid hydroxylases.
This book is comprised of 14 chapters and begins with an overview of the general properties and biological functions of oxygenases, along with the chemical aspects of oxygen fixation reactions. The reader is then introduced to research concerning fatty acid and steroid oxygenases which has appeared in the literature since 1962, paying particular attention to the mechanism of oxygenation and the biosynthesis and metabolism of steroids. Subsequent chapters explore the biological functions of a variety of oxygenases such as heme-containing dioxygenases, copper-containing oxygenases, flavoprotein oxygenases, and pterin-requiring aromatic amino acid hydroxylases. Superoxide dismutase, cytochrome c oxidase, peroxidase, and bacterial monoxygenases are also considered.
This monograph should serve as a valuable reference for biochemists as well as undergraduate and graduate students of biochemistry.

Contenu

List of Contributors

Preface

1. General Properties and Biological Functions of Oxygenases

   I. Historical Background

   II. Nomenclature, Classification, and General Properties of Oxygenases

   III. Chemical Aspects of Oxygen Fixation Reactions

   IV. Biological Function of Oxygenases

   V. Natural Distribution of Oxygenases

   References

2. Oxygenases in Fatty Acid and Steroid Metabolism

   I. Introduction

   II. Lipoxygenase

   III. Biosynthesis of Prostaglandins

   IV. Fatty Acid Hydroxylations

   V. Fatty Acid Desaturation

   VI. Biosynthesis of Cholesterol

   VII. Conversion of Cholesterol into Steroid Hormones

   VIII. Metabolism of Steroid Hormones in Liver

   IX. Biosynthesis and Metabolism of Bile Acids

   References

3. Heme-Containing Dioxygenases

   I. Introduction

   II. History of L-Tryptophan Oxygenase

   III. Biological Role and Distribution of Tryptophan Oxygenase

   IV. Physicochemical Properties of Tryptophan Oxygenase

   V. Catalytic Mechanism

   VI. Regulation of L-Tryptophan Oxygenase Activity

   VII. DL-Tryptophan Oxygenase of Rabbit Intestine

   References

   Supplementary References

4. Nonheme Iron Dioxygenase

   I. Introduction

   II. Catechol Dioxygenases

   III. Other Dioxygenases Requiring Nonheme Iron

   IV. Reaction Mechanism

   References

5. a-Ketoglutarate-Coupled Dioxygenases

   I. Introduction

   II. Prolyl Hydroxylase

   III. Lysyl Hydroxylase

   IV. 7-Butyrobetaine Hydroxylase

   V. Dioxygenases in Pyrimidine and Nucleoside Metabolism

   VI. p-Hydroxyphenylpyruvate Hydroxylase

   VII. General Discussion

   References

   Note Added in Proof

6. Microsomal Cytochrome P-450-Linked Monooxygenase Systems in Mammalian Tissue

   I. Introduction

   II. Catalytic Components

   III. Substrate Interaction with Cytochrome P-450

   IV. On the Mechanism of the Cytochrome P-450-Linked Monooxygenase Reaction

   V. On the Substrate Specificity of Microsomal Cytochrome P-450-Linked Monooxygenase Systems

   VI. Relationship of the Cytochrome P-450-Linked Monooxygenase System to the Microsomal Membrane

   VII. Substrate-Induced Synthesis of the Liver Microsomal Monooxygenase System

   References

7. Flavoprotein Oxygenases

   I. Introduction

   II. Internal Flavoprotein Monooxygenases

   III. External Flavoprotein Monooxygenases

   IV. External Flavoprotein Dioxygenase

   References

8. Pterin-Requiring Aromatic Amino Acid Hydroxylases

   I. Introduction

   II. Phenylalanine Hydroxylase

   III. Tyrosine Hydroxylase

   IV. Tryptophan Hydroxylase

   References

9. Copper-Containing Oxygenases

   I. Introduction

   II. Tyrosinases

   III. Dopamine ß-Hydroxylase

   IV. Quercetinase (Flavonol 2,4-Oxygenase)

   V. Conclusion

   References

10. Chemical Models and Mechanisms for Oxygenases

    I. Introduction

    II. General Characteristics of O2 and O2 Reactions

    III. Reactivity of Reduced O2 Species

    IV. The Oxenoid Mechanism

    V. Monooxygenases

    VI. Dioxygenases

    VII. Conclusions

    References

11. Superoxide Dismutase

    I. Introduction

    II. A Historical Account of the Discovery of Superoxide Dismutase

    III. Superoxide Dismutases from Eucaryotic Sources

    IV. Superoxide Dismutases from Procaryotic Sources

    V. Biological Significance of Superoxide Dismutase

    VI. Applications of Superoxide Dismutase

    VII. Some Chemical Properties of Oxygen and Its Reduction Products

    VIII. Projected Studies

    References

12. Cytochrome c Oxidase

    I. Introduction

    II. Physicochemical Properties

    III. Reaction Characteristics of the Isolated Enzyme

    IV. Interactions of Oxidase with the Membrane

    V. Conclusions

    References

13. Peroxidase

    I. Introduction

    II. Functions of Peroxidases

    III. Structure of Peroxidases

    IV. Relationship between Structure and Function

    V. Conclusion

    References

14. Bacterial Monoxygenases-The P450 Cytochrome System

    I. Introduction

    II. Bacterial Monoxygenases

    III. Biology

    IV. Chemistry and Physics

    V. Summary

    References

Author Index

Subject Index