Enzyme Regulation in Metabolic Pathwaysshows the reader how to understand the roles of enzymes and their kinetic constants in intermediary metabolism. It provides a means of correlating data obtained in experimental studies to multiple possible mechanisms through which some enzyme may catalyze the conversion of a substrate to a product. Although not the most appropriate means of determining some potential kinetic mechanism, quasi-equilibrium assumptions are used throughout the book, keeping the rate equation derivations simple. Actual metabolic pathways with known (presumed) positive and negative regulation events are linked to these potential kinetic mechanisms using both rate equation derivations and data plots illustrating how the rate equation derivations can be used to explain the data plots.

Preface vii

Authors Review ix

Part I 1 Characteristics of Enzymes 3

2 Self?-Assembly of Polymers 17

3 Beginnings of Equations 27

4 Metabolite Distribution Systems 37

5 Modification of Enzymatic Activity 51

6 Modification of Metabolite Flow Through Metabolic Pathways 67

7 Which is the Real Substrate? 75

8 Non?-Quasi-Equilibrium Assumptions 79

9 Underlying Attributes of Assessing Enzymatic Activities 85

Part II 10 Breakdown of the MichaelisMenten Equation (or Complex Enzyme Mechanisms) 97

11 Rate Equation Derivation by the KingAltman Method: Two Substrates and Two Products 117

12 Modification of Enzyme Mechanisms: The Next Generation 141

13 What Are These Rate Constants We Have Been Dealing With? 151

Index 165