Main description:

Enzymes perform the executive role in growth, energy conversion, and repair of a living organism. Their activity is adjusted to their en vironment within the cell, being turned off, switched on, or finely tuned by specific metabolites according to demands at the physiologi cal level. Each enzyme discovered in the long history of enzymology has revealed its own individuality. Even closely related members of a family differ in specificity, stability or regulatory properties. Despite these, at first sight overwhelming aspects of individuality, common factors of enzymic reactions have been recognized. Enzymes are stereospecific catalysts even when a nonspecific process would yield the same product. Knowledge of the detailed stereochemistry of an enzymic reaction helps to deduce reaction mechanisms and to ob tain insight into the specific binding of substrates at the active site. This binding close to catalytically competent groups is related to the enormous speed of enzyme-catalyzed reactions. The physical ba sis of rate-enhancement is understood in principle and further exploit ed in the design of small organic receptor molecules as model enzymes. These aspects of enzyme catalysis are discussed in Session 1. Session 2 emphasizes the dynamic aspects of enzyme substrate inter action. Substrate must diffuse from solution space to the enzyme's surface. This process is influenced and can be greatly facilitated by certain electrostatic propterties of enzymes. The dynamic events during catalysis are studied by relaxation kinetics or NMR techniques.

Contents:

Mechanism of Enzyme Action.- Stereochemistry in Relation to Enzyme Mechanism.- How Do Enzymes Work?.- Design of Synthetic Molecular Receptors and Catalysts.- Cyclodextrins as Catalysts.- Dynamics of Molecular Recognition.- Dynamics of Molecular Recognition Dynamics of Molecular Recognition in Enzyme-Catalyzed Reactions.- NMR in the Study of Enzyme Catalysis.- The Study of Enzyme Reactions at Subzero Temperatures.- Function of Metals in Enzymes: Thermophilic Enzymes.- Active Site Metals as Probes of Local Conformation and Function of Enzymes.- Selenoenzymes.- The Structure of the Selenoenzyme GSH Peroxidase.- Structure and Function of Thermophilic Enzymes.- Bilogical and Chemical Modifications of Enzymes.- Specific Enzyme Inactivators in Vitro and in Vivo.- Correlation of Amino Acid Sequence with Inhibitor Activity and Specificity of Protein Inhibitors of Serine Proteinases.- Human Latent PMN Leukocyte Collagenase and Regulation of Activity via Disulfide-Thiol Interchange as Catalyzed by the Glutathione Cycle.- The Neural and Hormonal Control of Glycogen Metabolism in Mammalian Skeletal Muscle.- Selected Topics of Enzyme Catalysis.- Bacterial Histidine Decarboxylase and Related Pyruvoyl Enzymes.- The Mechanism of Action of S-Adenosylhomocysteinase.- Studies of the Mechanism of Action of Urocanase.- Substrate-Carrier Interaction and the Catalytic Translocation Cycle of the ADP,ATP Carrier.