Biomembranes

This book will explain the colossal potential of life to cope with different living environments is possible owing to the exceptionally well developed mechanisms of adaptation to environmental conditions. There is an innumerable variety of concrete mechanisms which make it possible for living creatures to adapt to different and changing environmental conditions. Nevertheless, all this variety is the manifestation of the three strategic line of the adaptation process: 1. Evolutional or genotypic adaptation. 2. Phenotypic adaptation. 3. Rapid adaptation.

A coordinated approach using biochemical and immunological tools has given us a better understanding of the structure of the eukaryotic surface membrane. From such studies has emerged the fluid mosaic model of membrane structure and this volume contains a collection of articles written by noted workers in this field. A major emphasis in this area of research concerns the changes brought about on virus-induced and carcinogen-induced tumor cells. The first chapter comes from a laboratory that was one of the first to visualize the distribution of transplantation antigens on cell membrane surfaces. Various methods are described for visualizing these antigens by electron microscopy. Davis and his colleagues then proceed to show how the antibody-induced redistribution of antigenic macromolecules led to the formulation of the fluid mosaic model. From Hakomori's labora tory comes a methodological paper describing a novel method of labeling the carbohydrate portions of the membrane glycoproteins that are exposed on the outer surfaces of cells. The two chapters reviewing the changes found on carcinogen-induced and virus-induced malignant cells complete the survey of the structures associated with surface mem branes. Thanks are due to Mrs. Carol Garafolo who helped immeasurably with the preparation of the index for this volume.

New textbooks at all levels of chemistry appear with great regularity. Some fields like basic biochemistry, organic reaction mechanisms, and chemical thermody namics are well represented by many excellent texts, and new or revised editions are published sufficiently often to keep up with progress in research. However, some areas of chemistry, especially many of those taught at the graduate level, suffer from a real lack of up-to-date textbooks. The most serious needs occur in fields that are rapidly changing. Textbooks in these subjects usually have to be written by scientists actually involved in the research which is advancing the field. It is not often easy to persuade such individuals to set time aside to help spread the knowledge they have accumulated. Our goal, in this series, is to pinpoint areas of chemistry where recent progress has outpaced what is covered in any available textbooks, and then seek out and persuade experts in these fields to produce relatively concise but instructive introductions to their fields. These should serve the needs of one semester or one quarter graduate courses in chemistry and biochemistry. In some cases, the availability of texts in active research areas should help stimulate the creation of new courses.

This book describes how biologically available free energy sources (ATP, chemical potential, and membrane potentials, among others) can be used to drive synthetic reactions, signaling in cells, and various types of motion such as membrane traffic, active transport, and cell locomotion. As such, it approaches the concept of the energy cycle of life on Earth from a physical point of view, covering topics ranging from an introduction to chemical evolution, to an examination of the catalytic activity of enzymes associated with the genome in Darwinian evolution. The author introduces the relationship between functions and physical properties in biomembranes, explaining the methods and equipment used in biophysics research to help researchers unravel the still-unsolved mysteries of life. The physical principles needed to understand the cellular functions are provided; these functions are associated with biomembranes and regulated by physical properties of the lipid bilayer such as membrane fluidity, phase transition, and phase separation, as shown in lipid rafts. Other key dynamic aspects of life (cell locomotion, cytoskeletal dynamics, and sensitivities of the cell to physical stimuli such as external forces and temperature) are also discussed. Lastly, readers will learn how life on Earth and its ecological system are maintained by solar energy, and be provided further information on the problems accompanying global warming.

This book is about the importance of water in determining the structure, stability and responsive behavior of biological membranes. Water confers to lipid membranes unique features in terms of surface and mechanical properties. The analysis of the hydration forces, plasticiser effects, controlled hydration, formation of microdomains of confined water suggests that water is an active constituent in a water-lipid system. The chapters describe water organization at the lipid membrane–water interphase, the water penetration, the long range water structure in the presence of lipid membranes by means of X-ray and neutron scattering, general polarization, fluorescent probes, ATR-FTIR and near infrared spectroscopies, piezo electric methods, computer simulation and surface thermodynamics. Permeation, percolation, osmotic stress, polarization, protrusion, sorption, hydrophobicity, density fluctuations are treated in detail in self-assembled bilayers. Studies in lipid monolayers show the correlation of surface pressure with water activity and its role in peptide and enzyme interactions. The book concludes with a discussion on anhydrobiosis and the effect of water replacement in microdomains and its consequence for cell function. New definitions of lipid/water interphases consider water not only as a structural-making solvent but as a mediator in signalling metabolic activity, modulating protein insertion and enzymatic activity, triggering oscillatory reactions and functioning of membrane bound receptors. Since these effects occur at the molecular level, membrane hydration appears fundamental to understand the behavior of nano systems and confined environments mimicking biological systems. These insights in structural, thermodynamical and mechanical water properties give a base for new paradigms in membrane structure and function for those interested in biophysics, physical chemistry, biology, bio and nano medicine, biochemistry, biotechnology and nano sciences searching for biotechnological inputs in human health, food industry, plant growing and energy conversion.

This book describes methods used to investigate the function and distribution of lipids in membranes. Contributors present discoveries that have to do with lipid analysis and lipid interactions with other components of membranes, such as proteins, receptors, transporters and ion channels.

Membrane research holds a central position in cell and molecular biology. In recent years it has become clear that the study of membranes at the molecular level is of great importance not only to decipher all cellular processes but also to understand the alterations leading to abnormal cells (including cancer cells) and/or to understand the action of various drugs. This book covers the multidisciplinary approach of research in this area and the permanent need for information regarding recent advances. It will serve both workers studying basic aspects of membrane structure and function as well as medically oriented scientists. The selection of topics illustrating interconnections between basic and applied membrane biology will cross-fertilize research in both groups.