Artificial and Reconstituted Membrane Systems

This collection of 11 chapters is devoted to a survey of artificial and reconsti­ tuted membrane systems. These are fundamental themes and areas of great current importance in membrane biochemistry. They also relate well to the founding concept of this series, namely, to present studies that progressively work toward and provide us with an "integrated view of the cell. " In this volume, it is the application of a wide range of physiochemical and biochemi­ cal techniques to the study of membrane lipids and proteins which serves to demonstrate the significant progress that has been made in this field over the past 25 years. From the understanding of simplified artificial systems, it is hoped that it will ultimately be possible to gain a more accurate understanding of natural biological membranes, in all their diversity. This book is an appropriate successor to Volume 13 of the series, which deals with fluorescence studies on biological membranes. Indeed, the present chapter by Lesley Davenport and colleagues was originally due for inclusion in Volume 13, but has been held over for inclusion in this volume, where it integrates remarkably well with the other topics. The extremely varied and interesting contents of this volume are now briefly outlined. In Chapter I, Jacqueline A. Reynolds and Darrell R. McCaslin pres­ ent a pertinent survey of the interaction of detergents with membrane lipids and proteins, together with an assessment of the reconstitution process.

1 The Role of Detergents in Membrane Reconstruction.- 1. Introduction.- 2. The Membrane Environment.- 2.1. Lipid Components.- 2.2. Protein Components.- 3. Detergents.- 3.1. Types and Properties of Detergents.- 3.2. Modes of Interaction with Proteins.- 3.3. Interaction with Diacyl Lipid Bilayers.- 4. Reconstitution.- 4.1. Detergent-Lipid-Protein Interactions: A Reversible Process.- 4.2. Kinetics.- 4.3. Experimental Requirements for Lipid Vesicles.- 4.4. Experimental Procedures for Detergent-Induced Reconstitution.- 4.5. Kinetic Control of Vesicle Size.- 4.6. Incorporation of Intrinsic Membrane Proteins.- 5. Some Concluding Comments.- 6. References.- 2 Membrane Lipid Phase Behavior and Lipid-Protein Interactions.- 1. Introduction.- 2. Polymorphism of Membrane Polar Lipids.- 2.1. Biophysical Characterization of Membrane Lipid Polymorphism.- 2.2. Factors Responsible for Determining Lipid Phase.- 2.3. Phases of Pure Polar Lipids.- 2.4. Hexagonal Phases.- 2.5. Cubic and Other Nonlamellar Phases.- 3. Phase Bèhavior of Mixed Lipid Systems.- 3.1. Phase Behavior of Lipid Enantomers.- 3.2. Lateral Miscibility of Bilayer-Forming Lipids.- 3.3. Bilayer-Nonbilayer Phase Separations.- 4. Protein-Lipid Interactions.- 4.1. Exclusion of Proteins from Bilayer Gel Phases.- 4.2. Phase Separation of Nonbilayer Lipid Phases in Membranes.- 5. Conclusions.- 6. References.- 3 Reconstitution of Membrane Molecular Mechanisms in Bilayer Lipid Membranes and Patch-Clamp Bilayers.- 1. Introduction.- 2. Techniques for Formation and Characterization of Reconstituted Bilayers.- 2.1. Formation of Planar and Patch-Clamp Bilayers.- 2.2. Electrophysiological Methods for Analyzing the Properties of Reconstituted Membranes.- 3. Reconstitution of Membrane Molecular Mechanisms Related to Ion Transport and Excitability.- 3.1. Reconstitution of Sodium Ion Transport Mechanisms.- 3.2. Calcium Channels Functioning in Bilayers.- 3.3. Mechanisms of Potassium Ion Transport.- 3.4. Chloride Channels.- 3.5. Reconstitution of Active Transport Mechanisms in Planar Bilayers.- 4. Reconstitution of Synaptic Events.- 4.1. Acetylcholine-Receptor Mechanisms.- 4.2. Dopamine Receptors.- 5. Reconstitution of Sensory Mechanisms.- 5.1. Visual Receptor Membranes.- 5.2. Olfactory Receptors.- 6. Physiological Processes in Nonexcitable Membranes.- 6.1. Erythrocyte Plasma Membranes.- 6.2. Epithelial Membranes.- 6.3. Kidney Plasma Membranes.- 6.4. Ciliary Membranes.- 6.5. Outer Mitochondrial Membrane.- 7. Concluding Remarks and Perspective.- 8. References.- 4 Fluorescence Studies of Membrane Dynamics and Heterogeneity.- 1. Introduction.- 2. Do Domains Exist?.- 2.1. Thermal Effects.- 2.2. Chemically Induced Domain Formation.- 3. What Are the Relaxation Times for Lipid Domains?.- 4. Future Trends.- 5. References.- 5 Membrane Fusion: Fusogenic Agents and Osmotic Forces.- 1. Introduction.- 2. Fusogenic Lipids.- 2.1. Osmotic Effects.- 2.2. Cellular Proteases.- 2.3. Fusion Driven by Cell Swelling.- 3. Fusion Induced by Polyethylene Glycol.- 3.1. Purity of the Polymer.- 3.2. Dehydration.- 3.3. Rehydration.- 4. Electrically Induced Cell Fusion.- 5. Molecular Models for Membrane Fusion.- 6. Virally Induced Membrane Fusion i.- 7. Exocytosis.- 7.1. Model Systems.- 7.2. Biological Systems.- 8. References.- 6 Lectin-Carbohydrate Interactions in Model and Biological Membrane Systems.- 1. Introduction.- 2. Lectins: Abundance and Properties.- 2.1. Structural Features of Lectins.- 2.2. Carbohydrate Binding Properties.- 3. Glycolipids and Glycoproteins: Biological Receptors for Lectins.- 4. Lectin-Carbohydrate Interactions in Model Systems.- 4.1. Properties of Glycolipid-Containing Membranes.- 4.2. Lectin-Glycolipid Interactions.- 4.3. Interactions of Lectins with Glycoprotein-Containing Membranes.- 5. Lectin-Carbohydrate Interactions in Biological Systems.- 5.1. Exogenous Lectins: Applications.- 5.2. Exogenous Lectins: Biological Effects.- 5.3. Endogenous Lectins.- 6. References.- 7 Energy-Transducing Complexes in Bacterial Respiratory Chains.- 1. Introduction.- 2. Electron Transfer Chain and Energy Coupling.- 2.1. Bacterial Respiratory Chains.- 2.2. Two Approaches Using Whole Cells or Membrane Vesicles.- 3. Reconstitution into Liposomes.- 3.1. A Tool to Study Energy-Transducing Enzymes.- 3.2. Purification of Respiratory Complexes.- 3.3. Reconstitution Methods.- 4. Cytochrome Oxidase.- 4.1. Bacterial Cytochrome Oxidase.- 4.2. Reconstitution of Proton Pump Activity.- 4.3. Properties of Cytochrome aa3-Type Oxidases.- 4.4. Cytochrome 0-Type and d-Type Oxidases.- 5. Cytochrome bc1 Complexes.- 5.1. Properties.- 5.2. Reconstitution.- 6. NADH Dehydrogenases and Complex I.- 6.1. Membrane-Bound NADH Dehydrogenases.- 6.2. Evidence for Proton Pumping NADH: Quinone Oxidoreductase.- 6.3. Na+ Pumping NADH: Quinone Oxidoreductase.- 7. Energy-Transducing Components Other Than Complexes I-IV.- 7.1. Anaerobic Electron Transfer Systems.- 7.2. Transhy drogenase.- 8. Concluding Remarks and Outstanding Problems.- 9. References.- 8 Reconstitution of the High-Affinity Receptor for Immunoglobulin E.- 1. Introduction.- 2. Purification of the Receptor.- 2.1. Sensitivity to Detergent.- 2.2. Protective Effect of Lipids.- 2.3. Protocol for Purification.- 3. Mechanisms of Action of the Receptor: Possible Functions to Reconstitute.- 3.1. Role of Aggregation.- 3.2. Functions Associated with the Receptor-Mediated Triggering of Mast Cells.- 4. Reconstitution Studies.- 4.1. Planar Bilayers.- 4.2. Vesicles.- 5. Conclusions.- 6. References.- 9 Reconstitution of Acetylcholine Receptors into Planar Lipid Bilayers.- 1. Introduction.- 2. Technical Aspects of Acetylcholine-Receptor Reconstitution.- 2.1. Biochemical Procedures.- 2.2. Formation of Planar Lipid Bilayers.- 2.3. Incorporation of Proteins into Planar Lipid Bilayers.- 2.4. How to Collect and Process Data.- 3. Properties of Reconstituted Acetylcholine-Receptor Channels.- 4. Gating Models and Theoretical Aspects.- 5. Data from Other Experiments.- 6. Principal Requirements for a Functional Aeetylcholine-Receptor Channel.- 7. Summary and Conclusion.- 8. References.- 10 Liposomes as Carriers of Drugs: Observations on Vesicle Fate after Injection and Its Control.- 1. Introduction.- 2. Retention of Drugs by Liposomes in Contact with Blood.- 3. Circulation of Liposomes in the Blood.- 4. Distribution of Liposomes in Tissues.- 5. Conclusions.- 6. References.- 11 Reconstitution and Physiological Protein Translocation Processes.- 1. Introduction.- 2. Membrane Proteins and Protein Translocation Processes.- 2.1. Microsomal Membrane Proteins.- 2.2. Bacterial Membrane Proteins.- 2.3. Organellar Membrane Proteins.- 3. Energy Dependence of Protein Translocation Processes.- 3.1. Secretory and Transmembrane Integral Proteins.- 3.2. Migratory Proteins.- 4. Translocation and Membrane-Anchoring Signals.- 4.1. Signal and Membrane-Anchoring Sequences for Proteins Translocated through the Endoplasmic Reticulum and the Bacterial Cytoplasmic Membrane.- 4.2. Signal Sequences for Migratory Proteins.- 5. Post-Translational Protein Translocation.- 5.1. Post-Translational Translocation of Secretory and Transmembrane Integral Proteins t.- 5.2. Post-Translational Translocation of Migratory Proteins.- 5.3. Bound Ribosomes and Post-Translational Translocation of Migratory Proteins.- 5.4. The Case of Endoproteins.- 6. Protein Translocation through or Insertion into Lipid Aggregates.- 6.1. Experiments Related to Translocation of Secretory and Integral Membrane Proteins.- 6.2. Experiments on Translocation of Migratory Proteins.- 7. General and Concluding Remarks.- 8. References.