Introduction to Enzyme and Coenzyme Chemistry - E-Library Home

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Contents
4.5 The existence of intermediates in enzymatic reactions 68
4.6 Analysis of transition states in enzymatic reactions 71
4.7 Determination of active site catalytic groups 75
5 Enzymatic Hydrolysis and Group Transfer Reactions 81
5.1 Introduction 81
5.2 The peptidases 82
CASE STUDY: HIV-1 protease 96
5.3 Esterases and lipases 98
5.4 Acyl transfer reactions in biosynthesis: use of coenzyme A (CoA) 99
5.5 Enzymatic phosphoryl transfer reactions 102
5.6 Adenosine 5 0 -triphosphate 106
5.7 Enzymatic glycosyl transfer reactions 109
5.8 Methyl group transfer: use of S-adenosyl methionine and
tetrahydrofolate coenzymes for one-carbon transfers 112
6 Enzymatic Redox Chemistry 121
6.1 Introduction 121
6.2 Nicotinamide adenine dinucleotide-dependent dehydrogenases 123
6.3 Flavin-dependent dehydrogenases and oxidases 129
6.4 Flavin-dependent mono-oxygenases 134
6.5 CASE STUDY: Glutathione and trypanothione reductases 137
6.6 DeazaXavins and pterins 141
6.7 Iron–sulphur clusters 142
6.8 Metal-dependent mono-oxygenases 143
6.9 a-Ketoglutarate-dependent dioxygenases 147
6.10 Non-haem iron-dependent dioxygenases 148
7 Enzymatic Carbon–Carbon Bond Formation 156
7.1 Introduction 156
Carbon–carbon bond formation via carbanion equivalents 158
7.2 Aldolases 158
CASE STUDY: Fructose-1,6-bisphosphate aldolase 158
7.3 Claisen enzymes 164
7.4 Assembly of fatty acids and polyketides 166
7.5 Carboxylases: use of biotin 170
7.6 Ribulose bisphosphate carboxylase/oxygenase (Rubisco) 171
7.7 Vitamin K-dependent carboxylase 173
7.8 Thiamine pyrophosphate-dependent enzymes 176
Carbon–carbon bond formation via carbocation intermediates 179
7.9 Terpene cyclases 179
Carbon–carbon bond formation via radical intermediates 183
7.10 Phenolic radical couplings 184