Cover Page

Contents

Cover

Title Page

Copyright

Preface

Chapter 1: Enzymes Involved in Redox Reactions: Natural Sources and Mechanistic Overview

1.1 MOTIVATION: GREEN CHEMISTRY AND BIOCATALYSIS

1.2 SOURCES OF BIOCATALYSTS

1.3 OVERVIEW OF REDOX ENZYMES

1.4 CONCLUDING REMARKS

REFERENCES

Chapter 2: Natural Cofactors and Their Regeneration Strategies

2.1 TYPES OF NATURAL COFACTORS—MECHANISMS

2.2 COFACTOR REGENERATION

2.3 CONCLUDING REMARKS

REFERENCES

Chapter 3: Reactions Involving Dehydrogenases

3.1 GENERAL CONSIDERATIONS

3.2 REDUCTION OF CARBONYL GROUPS

3.3 RACEMIZATION AND DERACEMIZATION REACTIONS

3.4 PREPARATION OF AMINES

3.5 REDUCTION OF C–C DOUBLE BONDS

3.6 OXIDATION REACTIONS

3.7 DEHYDROGENASE-CATALYZED REDOX REACTIONS IN NATURAL PRODUCTS

3.8 CONCLUDING REMARKS

REFERENCES

Chapter 4: Reactions Involving Oxygenases

4.1 MONOOXYGENASE-CATALYZED REACTIONS

4.2 DIOXYGENASE-CATALYZED REACTIONS

4.3 CONCLUDING REMARKS

REFERENCES

Chapter 5: Reactions Involving Oxidases and Peroxidases

5.1 OXIDASE-CATALYZED REACTIONS

5.2 PEROXIDASE-CATALYZED REACTIONS

5.3 CONCLUDING REMARKS

REFERENCES

Chapter 6: Hydrolase-Mediated Oxidations

6.1 HYDROLASE PROMISCUITY AND IN SITU PERACID FORMATION. PERHYDROLASES VS. HYDROLASES. OTHER PROMISCUOUS HYDROLASE-MEDIATED OXIDATIONS

6.2 HYDROLASE-MEDIATED BULK OXIDATIONS IN AQUEOUS MEDIA (E.G., BLEACHING, DISINFECTION, ETC.)

6.3 LIPASE-MEDIATED OXIDATIONS: PRILESHAJEV EPOXIDATIONS AND BAEYER–VILLIGER REACTIONS

6.4 HYDROLASE-MEDIATED OXIDATION AND PROCESSING OF LIGNOCELLULOSIC MATERIALS

6.5 CONCLUDING REMARKS

REFERENCES

Chapter 7: Bridging Gaps: From Enzyme Discovery to Bioprocesses

7.1 CONTEXT

7.2 ENZYME DIRECTED EVOLUTION AND HIGH-THROUGHPUT-SCREENING OF BIOCATALYSTS

7.3 SUCCESSFUL CASE: BAKER'S YEAST REDOX ENZYMES, THEIR CLONING, AND SEPARATE OVEREXPRESSION

7.4 WHOLE-CELLS VS. ISOLATED ENZYMES: MEDIUM ENGINEERING

7.5 BEYOND: MULTISTEP DOMINO BIOCATALYTIC PROCESSES

7.6 CONCLUDING REMARKS

REFERENCES

Chapter 8: Industrial Applications of Biocatalytic Redox Reactions: From Academic Curiosities to Robust Processes

8.1 MOTIVATION: DRIVERS FOR INDUSTRIAL BIOCATALYTIC PROCESSES

8.2 KEY ASPECTS IN INDUSTRIAL BIOCATALYTIC PROCESSES

8.3 INDUSTRIAL BIOCATALYTIC REDOX PROCESSES: FREE ENZYMES

8.4 INDUSTRIAL BIOCATALYTIC REDOX PROCESSES—WHOLE-CELLS: THE “DESIGNER BUG” CONCEPT AND BEYOND (METABOLIC ENGINEERING)

8.5 CONCLUDING REMARKS AND FUTURE PERSPECTIVES

REFERENCES

Index

Title Page

PREFACE

The use of enzymes for redox processes has gained an increasing interest in the last decades, becoming in many cases “the first choice” for scouting novel industrial synthetic routes. This has been realized by solving issues related to cofactor regeneration, often needed for these enzymes, together with the developments in molecular biology areas that have enabled the provision of enzymes in large and reproducible scale in a fermentative sustainable manner. The development of environmentally sound synthetic protocols is mandatory in this century and, in this regard, oxidoreductases are ideally suited to the task, providing efficient and green alternatives to conventional synthetic procedures. This is particularly remarkable in oxidative processes, where oxidases and oxygenases perform clean and selective oxidations by activation of molecular oxygen with no need of heavy metals or expensive chemocatalysts. On the reductive side, these enzymes find ample application in the industry and academia for the generation of enantioenriched compounds.

This book provides a comprehensive and updated overview on the use of redox enzymes and enzyme-mediated oxidative processes. Chapters 1 and 2 provide an introduction on biochemical features of redox enzymes, together with aspects related to cofactors, and cofactor regeneration methods. Chapters 3–5 describe in detail the biocatalytic applications of different redox enzymes, namely, dehydrogenases (Chapter 3), oxygenases (Chapter 4), and oxidases and peroxidases (Chapter 5). Enzyme-mediated oxidative processes based on biocatalytic promiscuity (e.g., of hydrolases) are covered in Chapter 6. Chapter 7 focuses on the necessary steps starting from the discovery of a certain enzyme with a catalytic activity to a robust industrial process (e.g., directed evolution, high-throughput-screening methods, and medium engineering). Last but not least, Chapter 8 provides an overview on industrial cases using oxidoreductases, already commercialized or close to, showing that academic research is ending up with successful cases at the industrial arena. Overall, we believe that our contribution may well serve as a complete and first approach to academic and industrial research groups in the field of redox biocatalysis. It is our hope that readers will find this book an attractive and useful tool.

Finally, we would like to acknowledge Ms. Anita Lekhwani, Senior Acquisitions Editor at John Wiley & Sons, as well as the whole editorial team for the trust, hard work, interest, and patience that they have put into this project.

DANIELA GAMENARA
GUSTAVO SEOANE
PATRICIA SAENZ-MÉNDEZ
PABLO DOMÍNGUEZ DE MARÍA

Montevideo, Uruguay, and Aachen, Germany,
December 2011