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This book provides a molecular view of membrane transport by means of numerous biochemical and biophysical techniques. The rapidly growing numbers of atomic structures of transporters in different conformations and the constant progress in bioinformatics have recently added deeper insights. The unifying mechanism of energized solute transport across membranes is assumed to consist of the conformational cycling of a carrier protein to provide access to substrate binding sites from either side of a cellular membrane. Due to the central role of active membrane transport there is considerable interest in deciphering the principles of one of the most fundamental processes in nature: the alternating access mechanism. This book brings together particularly significant structure-function studies on a variety of carrier systems from different transporter families: Glutamate symporters, LeuT-like fold transporters, MFS transporters and SMR (RND) exporters, as well as ABC-type importers. The selected examples impressively demonstrate how the combination of functional analysis, crystallography, investigation of dynamics and computational studies has made it possible to create a conclusive picture or more precisely, “a molecular movie”. Although we are still far from a complete molecular description of the alternating access mechanism, remarkable progress has been made from static snapshots towards membrane transport dynamics.

Newer Methods of Nutritional Biochemistry: With Applications and Interpretations, Volume III, provides a compilation of biochemical procedures which have extensive applications in nutrition research. The focus is on simple procedures to evaluate the utilization of dietary proteins given the pressing problems in emergency feeding of populations in developing countries. Comprised of nine chapters, this book discusses the nutritional and metabolic implications of changes in urinary amino acid levels. It examines the concept, role, and implications of protein reserves in the young and adult subjects. It also describes procedures which have contributed to the development of in vitro methods for the evaluation of protein quality. The book also discusses plant protein resources; lipoprotein transport; chemical assay of adrenocorticosteroids; studies of zinc metabolism; and folates in human nutrition.

This is the third volume in this series covering protein translocation within and between cells. Volumes 31 and 32, Vesicular Transport, Parts A and B, treated techniques for eukaryotic cells available as of 1989. Vectorial Transport of Proteins into and across Membranes, brings together new methods and new topics as of 1991. Highlights include use of anti-idiotype antibodies, gene fusions, transcription, crosslinking, pulse-labeling, and reconstitution. - Describes contemporary approaches for studying protein transport, protein topology and organelle biogenesis - Covers methods from pre-eminent laboratories including: In vitro and in vivo investigations; Biochemical and immunological techniques; Prokaryote, chloroplast, mitochondria, peroxisome, and rough endoplasmic reticulum membranes

The incentive for putting together Volume 4 of this series was to review the wealth of new information that has become available in prokaryotic organisms in protein export and membrane biogenesis. Just in the last several years, protein translocation has now been efficiently reconstituted using defined components and the mechanism by which proteins are moved across membrane bilayers is now being examined at a higher resolution. In addition, because of a new technical breakthrough using osmolytes, it is now possible to reconstitute a number of channel proteins, ATPase, receptors, and transporters. In many cases, it is possible to successfully predict the membrane topology of these types of proteins using both'hydrophobicity analysis'and the'positive inside'rule. In this volume, two chapters focus on protein translocation across membranes (Biochemical Analyses of Components Comprising the Protein Translocation Machinery of E. Coli; Protein Translocation Genetics), while several others on how proteins assemble into the ineer membrane of E. Coli (Membrane Protein Assembly; Membrane Insertion of Small Proteins: Evolutionary and Functional Aspects; Pigment-Protein Complex Assembly in Rhodobacter sphaeroides and Rhodobacter Capsulatus). Other sections review recent progress on transporters (Identification and Reconstitution of Anion Exchange Mechanisms in Bacteria; Helic Packing in the C-Terminal Half of Lactose Permease) and signal transduction (Mechanism of Transmembrane Signaling in Osmoregulation) as well as the assembly of prints into the outer membrane (Export and Assembly of Outer Membrane Proteins in E. coli). Although the emphasis of the book is on proteins, the role of phospholipids in controlling various cell surface processes is reviewed (Role of Phospholipids in coli Cell Function). I should point out the reason for the rapid progress in bacteria research is because of the possibility to apply biochemistry and genetics in this organism.

Bacterial Energetics deals with bacterial energetics and the molecular basis of how ions move between and within energy-transducing molecules. Topics covered range from respiration-driven proton pumps and primary sodium pumps to light-driven primary ionic pumps, bacterial transport ATPases, and bacterial photosynthesis. Sodium-coupled cotransport and ion-exchange systems in prokaryotes are also considered. This volume is comprised of 17 chapters and begins with an analysis of the pumps and processes that establish electrochemical ion gradients across bacterial membranes, followed by a discussion on the major types of bioenergetic work that utilize these gradients. The energetics of periplasmic transport systems, chemolithotrophs, methanogens, and protein insertion and translocation into or across membranes are also examined, along with bioenergetics in extreme environments such as high-pressure and high-temperature environments; energetic problems of bacterial fermentations; energetics of bacterial motility; and energetics of the bacterial phosphotransferase system in sugar transport and the regulation of carbon metabolism. This book should be of interest to molecular biologists and biochemists.