The Photosynthetic Bacterial Reaction Center


Book Description

This volume contains the contributions from the speakers at the NATO Advanced Research Workshop on "Structure of the Photosynthetic Bacterial Reaction Center X-ray Crystallography and Optical Spectroscopy with Polarized Light" which was held at the "Maison d'Hotes" of the Centre d'Etudes Nucleaires de Cadarache in the South of France, 20-25 September, 1987. This meeting continued in the spirit of a previous workshop which took place in Feldafing (FRG), March 1985. Photosynthetic reaction centers are intrinsic membrane proteins which, by performing a photoinduced transmembrane charge separation, are responsible for the conversion and storage of solar energy. Since the pioneering work of Reed and Clayton (1968) on the isolation of the reaction center from photosynthetic bacteria, optical spectroscopy with polarized light has been one of the main tools used to investigate the geometrical arrangement of the various chromophores in these systems. The recent elucidation by X-ray crystallography of the structure of several bacterial reaction centers, a breakthrough initiated by Michel and Deisenhofer, has provided us with the atomic coordinates of the pigments and some details about their interactions with neighboring aminoacid residues. This essential step has given a large impetus both to experimentalists and to theoreticians who are now attempting to relate the X-ray structural model to the optical properties of the reaction center and ultimately to its primary biological function.




Photosynthetic Reaction Center


Book Description

The availability of the photosynthetic reaction center's structure at an atomic resolution of less than three angstroms has revolutionized research. This protein is the first integral membrane protein whose structure has been determined with such precision. Each volume of the Photosynthetic Reaction Center contains original research, methods, and reviews. Together, these volumes cover our current understanding of how photosynthesis converts light energy into stored chemical energy.Volume I describes the chemistry and biochemistry of photosynthesis, including green plant photosynthesis; it is devoted to the overall features and implications of the bacterial reaction center for green plant research. It features a new description of the structure of the reaction center, followed by coverage of the antenna and light functions. Volume I also details new manipulations of the reaction center including chemical and genetic modifications. It describes how the reaction center provides reducing power via electron transfer chemistry coupled to proton uptake and release; coupling of electron transport between the oxidized reaction center and the aqueous periplasm; and the general operation of membrane-bound proteins. Additionally, this volume contains five chapters detailing facets of green plant photosynthesis important for future research.




The Reaction Center of Photosynthetic Bacteria


Book Description

Results of this third Feldafing Meeting can be considered as the harvest of novel techniques in spectroscopy, biochemistry and molecular biology to the bacterial photosynthetic reaction center. New information pertains to the crystallographic and electronic structure as well as to the dynamics of primary events and the role of the protein. The answer to one long-standing problem, the mechanism of primary charge separation, converges towards a sequential scheme, supported by femtosecond spectroscopy on reaction centers with selectively modified energetics.




Oxygenic Photosynthesis: The Light Reactions


Book Description

Structure and function of the components of the photosynthetic apparatus and the molecular biology of these components have become the dominant themes in advances in our understanding of the light reactions of oxygenic photosynthesis. Oxygenic Photosynthesis: The Light Reactions presents our current understanding of these reactions in thylakoid membranes. Topics covered include the photosystems, the cytochrome b6-f complex, plastocyanin, ferredoxin, FNR, light-harvesting complexes, and the coupling factor. Chapters are also devoted to the structure of thylakoid membranes, their lipid composition, and their biogenesis. Updates on the crystal structures of cytochrome f, ATP synthase and photosystem I are presented and a section on molecular biology and evolution of the photosynthetic apparatus is also included. The chapters in this book provide a comprehensive overview of photosynthetic reactions in eukaryotic thylakoids. The book is intended for a wide audience, including graduate students and researchers active in this field, as well as those individuals who have interests in plant biochemistry and molecular biology or plant physiology.




The Photosynthetic Reaction Center


Book Description

The availability of the photosynthetic reaction center's structure at an atomic resolution of less than three angstroms has revolutionized research. This protein is the first integral membrane protein whose structure has been determined with such precision. Each volume of the Photosynthetic Reaction Center contains original research, methods, and reviews. Together, these volumes cover our current understanding of how photosynthesis converts light energy into stored chemical energy. Volume II details the electron transfer process; it is oriented to the physical aspects of photosynthesis. It thus ...




The Photosynthetic Bacterial Reaction Center II


Book Description

The NATO Advanced Research Workshop entitled "The Photosynthetic Bacterial Reaction Center: Structure, Spectroscopy, and Dynamics" was held May 10-15, 1992, in the Maison d'H6tes of the Centre d'Etudes Nuc1eaires de Cadarache near Aix-en-Provence in the south of France. This workshop is the most recent of a string of meetings which started in Feldafing (Germany) in March 1985, soon after the three-dimensional structure of the bacterial reaction center had been elucidated by X-ray crystallography. This was followed, in September 1987, by a workshop in Cadarache and, in March 1990, by a second meeting in Feldafing. Although one of the most important processes on Earth, photosynthesis is still poorly understood. Stimulated by the breakthrough of solving the bacterial reaction center structure at atomic resolution, the field of relating this structure to the function of the reaction center, i. e. the remarkably efficient conversion and storage of solar energy, has been developing vigorously. Once the general organization of the cofactors and some details of the protein-cofactor interactions were known, it became possible to combine a variety of spectroscopic techniques with the powerful tool of site-directed mutagenesis in order to address increasingly incisive questions about the specific role of some amino acid residues in the electron transfer process. Still another promising tool is being developed, namely the exchange of a number of the native bacteriochlorophyll and bacteriopheophytin cofactors by chemically modified pigments.







Current topics in photosynthesis


Book Description

Four decades ago, when Lou Duysens was about to start his work on fluo rescence and energy transfer in photosynthesis that would lead to his thesis [1], very little was known about the molecular mechanisms of photosyn thesis, certainly from our present-day point of view. However, this state of affairs would rapidly change in the ensuing years by the introduction of modern physical and biochemical techniques. Especially the field of optical spectroscopy, on which the work of Duysens had such a significant impact, has proved to be one of the most fruitful techniques in the study of primary processes and electron transfer reactions in photosynthesis. Duysens' thesis established the role of energy transfer in photosynthesis and also showed for the first time the existence in photosynthetic bacteria of light-induced absorbance changes of what is now known as the primary electron donor P-870. Subsequent studies by the same method demonstrated the photo-oxidation of cytochromes, both in bacteria [2] and in algae [3,4] and of the absorbance changes [3] that were later found to be due to electro chromic band shifts of antenna pigments. Measurements of cyto chrome kinetics in light of various wavelengths led to the concept of two photosystems in green plant photosynthesis [5], whereas a study of the factors affecting the fluorescence yield of chlorophyll gave the first infor mation on the electron acceptor Q of photo system II [6].




The Photosynthetic Reaction Center


Book Description

The availability of the photosynthetic reaction center's structure at an atomic resolution of less than three angstroms has revolutionized research. This protein is the first integral membrane protein whose structure has been determined with such precision. Each volume of the Photosynthetic Reaction Center contains original research, methods, and reviews. Together, these volumes cover our current understanding of how photosynthesis converts light energy into stored chemical energy. Volume I describes the chemistry and biochemistry of photosynthesis, including green plant photosynthesis; it is devoted to the overall features and implications of the bacterial reaction center for green plant research. It features a new description of the structure of the reaction center, followed by coverage of the antenna and light functions. Volume I also details new manipulations of the reaction center including chemical and genetic modifications. It describes how the reaction center provides reducing power via electron transfer chemistry coupled to proton uptake and release; coupling of electron transport between the oxidized reaction center and the aqueous periplasm; and the general operation of membrane-bound proteins. Additionally, this volume contains five chapters detailing facets of green plant photosynthesis important for future research.




Photosynthesis: Structures, Mechanisms, and Applications


Book Description

To address the environmental, socioeconomic, and geopolitical issues associated with increasing global human energy consumption, technologies for utilizing renewable carbon-free or carbon-neutral energy sources must be identified and developed. Among renewable sources, solar energy is quite promising as it alone is sufficient to meet global human demands well into the foreseeable future. However, it is diffuse and diurnal. Thus effective strategies must be developed for its capture, conversion and storage. In this context, photosynthesis provides a paradigm for large-scale deployment. Photosynthesis occurs in plants, algae, and cyanobacteria and has evolved over 3 billion years. The process of photosynthesis currently produces more than 100 billion tons of dry biomass annually, which equates to a global energy storage rate of ~100 TW. Recently, detailed structural information on the natural photosynthetic systems has been acquired at the molecular level, providing a foundation for comprehensive functional studies of the photosynthetic process. Likewise, sophisticated spectroscopic techniques have revealed important mechanistic details. Such accomplishments have made it possible for scientists and engineers to construct artificial systems for solar energy transduction that are inspired by their biological counterparts. The book contains articles written by experts and world leaders in their respective fields and summarizes the exciting breakthroughs toward understanding the structures and mechanisms of the photosynthetic apparatus as well as efforts toward developing revolutionary new energy conversion technologies. The topics/chapters will be organized in terms of the natural sequence of events occurring in the process of photosynthesis, while keeping a higher-order organization of structure and mechanism as well as the notion that biology can inspire human technologies. For example, the topic of light harvesting, will be followed by charge separation at reaction centers, followed by charge stabilization, followed by chemical reactions, followed by protection mechanisms, followed by other more specialized topics and finally ending with artificial systems and looking forward. As shown in the table of contents (TOC), the book includes and integrates topics on the structures and mechanisms of photosynthesis, and provides relevant information on applications to bioenergy and solar energy transduction.