The Expert Committee on Biomaterials and Biotechnology for the European and the North American Region was founded by the General Assembly of UNESCO at its 21st Session, in 1981. The Committee comprises a Coordinating Group and four working Groups, defined in the following scientific areas: Group I Proteins: source, structure and function. Group II Nucl~ic acids: the hereditary materials. Group III Im~une materials and mechanisms. Membranes and transport in biosystems. Group IV In fulfilment of one of the objectives of the Committee, which have been adopted by the General Assembly of UNESCO in 1981, namely the intensification of the exchange of scientific information on biomaterials and biotechnology, working Group IV organized an international workshop on Ion Interactions in Energy Transport Systems, which was convened in Athens, Greece, from 8 to 12 April, 1985. Scientific papers presented at that workshop make up the chapters presented in this volume. The present volume focusses on natural and artificial membranes that are involved in energy transduction. Several chapters are devoted to membranes and membrane components that convert and utilize light, such as the thylakoid membrane of oxygenic photosynthetic organisms (eukaryotic and prokaryotic), the chromatophore membrane of nonoxygenic photosynthetic bacteria and the purple membrane of the halophilic bacteria. Other systems examined include the mitochondrial membranes and their adenine nucleotide carrier, the plasma membrane of animal cells, and lipid bilayer vesicles, either reconstituted or not, with enzymes.

Chlorophyll a Fluorescence: A Signature of Photosynthesis highlights chlorophyll (Chl) a fluorescence as a convenient, non-invasive, highly sensitive, rapid and quantitative probe of oxygenic photosynthesis. Thirty-one chapters, authored by 58 international experts, provide a solid foundation of the basic theory, as well as of the application of the rich information contained in the Chl a fluorescence signal as it relates to photosynthesis and plant productivity. Although the primary photochemical reactions of photosynthesis are highly efficient, a small fraction of absorbed photons escapes as Chl fluorescence, and this fraction varies with metabolic state, providing a basis for monitoring quantitatively various processes of photosynthesis. The book explains the mechanisms with which plants defend themselves against environmental stresses (excessive light, extreme temperatures, drought, hyper-osmolarity, heavy metals and UV). It also includes discussion on fluorescence imaging of leaves and cells and the remote sensing of Chl fluorescence from terrestrial, airborne, and satellite bases. The book is intended for use by graduate students, beginning researchers and advanced undergraduates in the areas of integrative plant biology, cellular and molecular biology, plant biology, biochemistry, biophysics, plant physiology, global ecology and agriculture.