Beschreibung
The value of studies of monotypic populations is constantly argued in bacterial ecology. The controversy itself is evidenceofthe strong awareness that bacterial activities in natural sites are not determined by the bacteria alone. At the same time, the best evidence that bacteria are influenced by environmental factors is the contrast between their behavior in laboratory cultures and their relatively subdued influence when in the presence of com petitors, predators, and fluctuating-often stressful-environmental conditions. Monotypic populations are admittedly reductionist, but are not therefore irrelevant to bacterial ecology. Quite the contrary. Without pure culture studies, our understanding of important and applicable bacterial activities-N fixation, for example-would still be z limited to what we could discern from a comparison of events in steamed vis-a-vis un heated soil. As was evident throughout the previous volume in this treatise, practically any method of studying natural bacterial communities upsets them while permitting only limited assessment of the respective qualities and quantitative contributions to total com munity activity of each type of bacterium present. Total activity itself is difficult to assess and is not dependably accomplished by any single method. This third volume comprises information regarding the properties of bacteria as they have been learned largely from pure culture studies. Its purpose is twofold: to provide readers with fundamental information regarding the cellular organization, physiological capabilities, and genetic systems of bacteria; and to connect known bacterial properties with environmental influences on them and with their influences on natural processes.
Autorenporträt
Inhaltsangabe1 The Structure of Bacteria.- A Fundamental Design for Bacteria.- Problems in Interpretation.- Design Rationale.- Shape and Form.- Execution and Maintenance of Shape.- Necessity of Organelles.- Concept of the Periplasm.- The Plasma Membrane.- Intracytoplasmic Continuations of the Plasma Membrane.- Discrete Organelles within the Cytoplasm.- Membranous Organelles, Membrane-Bound Granules, and Non-Membrane-Bound Granules.- Nucleoplasm.- Dividing Cells.- Organelles Associated with the Cell Surface.- Flagella.- Pili or Fimbriae.- Spinae.- The Cytosol.- Bacteria in Nature.- Concluding Remarks.- References.- 2 Growth and Survival of Bacteria.- Growth of Bacteria.- Essential Nutrient Requirements.- Nutrient Supply in the Natural Environment.- Influence of Other Environmental Factors.- Growth on Laboratory Media.- Survival of Bacteria.- General Problem of Survival.- Specialized Mechanisms for Survival.- Significance of Reserve Materials.- Survival in Soil and Water.- Survival of Phototrophs on Starvation.- Rumen Bacteria.- Role of the Bacterial Membrane.- Anaerobes and the Role of the Membrane Potential in Survival.- Conclusions.- References.- 3 Chemistry and Metabolism of Intracellular Reserves.- Criteria for Classification of a Substance Having Energy-Storage Function.- Glycogen and Other ?-1,4-Glucans.- Occurrence in Bacteria.- Biological Functions of Bacterial Glycogen.- Structural Studies.- Enzymatic Reactions Involved in Glycogen Synthesis.- Regulation of the ADP-Glucose Pathway to Glycogen Synthesis.- Genetic Regulation of Glycogen Synthesis.- Cloning of the Glycogen Biosynthetic Enzyme Structural Genes of E. coli.- Degradation of Bacterial Glycogen.- d(-)-Poly-?-Hydroxybutyric Acid.- Occurrence.- Chemistry and Structural Studies of Poly-?-Hydroxybutyrate.- Chemical Synthesis of d-Poly-?-Hydroxybutyrate.- Composition and Structure of Polyhydroxybutyrate Granules.- Estimation of Poly-?-Hydroxybutyrate.- Physiological Conditions Causing Poly-?-Hydroxybutyrate Accumulation.- Enzymatic Reactions Involved in Synthesis and Degradation of Poly-?-Hydroxybutyrate.- Degradation of Poly-?-Hydroxybutyrate.- Functions of Poly-?-Hydroxybutyrate.- Polyphosphate.- Occurrence of Polyphosphates in Microorganisms.- Chemical Structure of the Polyphosphates.- Detection and Estimation of Polyphosphate.- Synthesis and Utilization of Polyphosphate in Bacteria.- Polyphosphate Accumulation and Utilization in Yeast.- Enzymatic Aspects of Polyphosphate Synthesis.- Regulation of Polyphosphate Metabolism.- Physiological Functions of Polyphosphate.- General Conclusions.- References.- 4 Chemical Unity and Diversity in Bacterial Catabolism.- Physiological Determinants of Degradative Pathways: The Need to Satisfy Energy Requirements in a Variety of Environments.- Bacterial Catabolism and the Terrestrial Carbon Cycle.- Some Thermodynamic Considerations.- Energy-Rich Compounds as Biochemical Reagents.- Bacterial Degradation and Availability of Oxygen.- Substrate-Level Phosphorylations.- Enzymes Used to Prepare the Structures of Growth Substrates for Participation in Energy-Yielding Processes.- Aldolases, Thiolases, ?-Diketone Hydrolases, and ?-Decarboxylases.- Modification of the Chemical Structure of a Metabolite Prior to Its Breakdown.- Degradation of Catabolites Formed by Opening the Benzene Nucleus.- Initiating Attack on Bacterial Growth Substrates.- Dioxygenases.- Aromatic Hydroxylases.- Alicyclic Compounds as Substrates for Mono-Oxygenases.- Amino Acid Catabolism.- Bacterial Degradation of Synthetic Compounds.- Cometabolism.- Summary of Degradation by Meta-Fission.- Degradation of Aromatics by Ortho-Fission.- Release of Methanol and Halide Ions from Aromatics.- Abiotic Transformation of Environmental Pollutants.- Summary.- References.- 5 Biotic and Abiotic Release of Inorganic Substances Exploited by Bacteria.- Nature of the Inorganic Environment.- Mineral Substrates.- Decomposition of Rocks and Minerals.- Conditions Supporting Microbe-Mediated Release of In
