Page 12 - Cascade biocatalysis

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12.5 Conclusions 279
Acknowledgment 279
References 280

13 Key-Study on the Kinetic Aspects of the In Situ NHase/AMase Cascade
System of M. imperiale Resting Cells for Nitrile Bioconversion 283
Laura Cantarella, Fabrizia Pasquarelli, Agata Spera, Ludmila
Mart´ınkov´a, and Maria Cantarella
13.1 Introduction 283
13.2 The Temperature Effect on the NHase–Amidase Bi-Enzymatic
Cascade System 284
13.3 Effect of Nitrile Concentration on NHase Activity and Stability 287
13.4 Effect of Nitrile on the AMase Activity and Stability 289
13.5 Concluding Remarks 293
Acknowledgments 293
References 293

14 Enzymatic Stereoselective Synthesis of -Amino Acids 297
Varsha Chhiba, Moira Bode, Kgama Mathiba, and Dean Brady
14.1 Introduction 297
14.2 Preparation of β-Amino Acids 298
14.2.1 Chemical Methods for Generating β-Amino Acids 298
14.2.2 Biocatalytic Preparation of Enantiopure β-Amino Acids 299
14.2.2.1 Lipases and Aminoacylases 299
14.2.2.2 Transaminases 300
14.2.2.3 Nitrile Converting Biocatalysts 300
14.3 Nitrile Hydrolysis Enzymes 301
14.3.1 Nitrilase 301
14.3.1.1 Nitrilase Structure and Mechanism 301
14.3.1.2 Nitrilase Substrate Selectivity 302
14.3.2 Nitrile Hydratase 302
14.3.2.1 Nitrile Hydratase Structure and Mechanism 303
14.3.3 Amidases 304
14.3.3.1 Amidase Structure and Mechanism 304
14.3.4 Nitrile Hydratase and Amidase Cascade Substrate Selectivity 304
14.4 Conclusion 308
Acknowledgments 309
References 309
15 New Applications of Transketolase: Cascade Reactions for Assay
Development 315
Laurence Hecquet, Wolf-Dieter Fessner, Virgil H´elaine, and Franck
Charmantray
15.1 Introduction 315
15.2 Cascade Reactions for Assaying Transketolase Activity In Vitro 317