Photosynthesis II

I. Introduction.- II. CO2 Assimilation.- II A. The Reductive Pentose Phosphate Cycle.- 1. The Reductive Pentose Phosphate Cycle and Its Regulation.- A. Introduction.- B. The Reductive Pentose Phosphate Cycle.- I. The Cyclic Path of Carbon Dioxide Fixation and Reduction.- II. Individual Reactions of the RPP Cycle.- III. Stoichiometry and Energetics.- C. Utilization of the Products of the RPP Cycle.- I. Starch Synthesis.- II. Triose Phosphate Export.- III. Glycolate Formation.- D. Mapping the RPP Cycle.- I. Early History.- II. First Products of CO2 Fixation.- III. Sugar Phosphates.- IV. Studies of Light-Dark and High-Low CO2 Transients.- V. Discovery of Enzymes of the RPP Cycle.- E. Metabolic Regulation of the RPP Cycle.- I. In Vivo Kinetic Steady-State Studies with Labeled Substrates.- II. Light-Dark Regulation.- III. Regulation of the RPP Cycle During Photosynthesis.- F. Concluding Remarks.- References.- 2. The Isolation of Intact Leaf Cells, Protoplasts and Chloroplasts.- A. Introduction.- B. Isolation of Plant Leaf Cells and Protoplasts.- I. Mechanical Methods.- II. Enzymic Methods.- III. Cell and Protoplast Isolation from C3 and C4 Grasses.- C. Isolation of Intact Chloroplasts.- I. Plant Material and Media.- II. Isolation Methods.- III. Chloroplast Isolation from Other Plants.- References.- 3. Studies with the Reconstituted Chloroplast System.- A. Reconstituted Chloroplast Systems.- I. Introduction.- II. Definition.- III. Methods of Preparation.- IV. Activities Achieved.- V. Advantages and Drawbacks.- B. Factors Affecting the Activity of Partial Reaction Sequences in Reconstituted Chloroplast Systems.- I. The Light Reactions.- II. The Conversion of 3-Phosphoglycerate to Triose Phosphate.- III. The Conversion of Triose Phosphate to Pentose Phosphate.- IV. The Conversion of Ribulose-5-Phosphate to Ribulose-1, 5-Bisphosphate.- V. The Fixation of Carbon Dioxide.- VI. Autocatalysis.- C. Reconstituted Chloroplast Systems and the Regulation of Photosynthesis.- I. The Role of Magnesium, pH and Reductants.- II. The Role of the ATP/ADP Ratio.- References.- 4. Autotrophic Carbon Dioxide Assimilation in Prokaryotic Microorganisms.- A. Introduction.- B. Principles of Autotrophic Carbon Dioxide Assimilation in Prokaryotic Cells.- C. The Pathway of Carbon Dioxide Assimilation in Green Sulfur Bacteria.- D. The Pathway of Carbon Dioxide Assimilation in Purple Bacteria.- E. The Pathway of Carbon Dioxide Assimilation in Blue-Green Algae.- F. The Pathway of Carbon Dioxide Assimilation in Chemolithotrophic Bacteria.- G. Regulatory Aspects of Carbon Dioxide Assimilation in Prokaryotic Microorganisms.- References.- 5. Light-Enhanced Dark CO2 Fixation.- A. Light-Enhanced Dark CO2 Fixation in C3 Plants.- I. Introduction.- II. Capacity for Light-Enhanced Dark CO2 Fixation.- III. Products.- IV. RuBP, NADPH, and ATP Levels.- V. Fate of PGA.- VI. Higher Plants.- B. Light-Enhanced Dark CO2 Fixation in C4 Plants.- References.- II B. The C4 and Crassulacean Acid Metabolism Pathways.- 6. The C4 Pathway and Its Regulation.- A. Discovery of C4 Photosynthesis.- B. Kranz Leaf Anatomy.- I. Variations in Leaf Anatomy.- C. Environmental Regulation of C4 Photosynthesis.- I. Light Intensity.- II. CO2 Concentration.- III. O2 Concentration.- IV. Temperature.- V. Water.- VI. Salinity.- VII. Nitrogen Supply.- D. Biochemical Schemes for the C4 Pathway.- E. Regulation via Enzymatic and Metabolic Compartmentation into Leaf Cell Types.- F. Efficiency of C4 Leaf Photosynthesis.- I. CO2 Pools.- II. CO2 Trapping.- III. CO2 Fixation by Bundle Sheath Cells.- G. C3–C4 Intermediate Plants.- H. Criteria for the Presence of C4 Photosynthesis.- I. Conclusions in the Regulation of C4 Photosynthesis in Leaves.- References.- 7. C4 Metabolism in Isolated Cells and Protoplasts.- A. Introduction.- B. Three Groups of C4 Plants.- C. Localization of Enzymes of C4 Metabolism in C4 Plants.- I. Intercellular Localization.- II. Intracellular Localization.- D. Criteria for Intactness of Cellular Preparations.- I. Mesophyll Preparations.- II. Bundle Sheath Preparations.- E. Variations in C4 Metabolism.- I. Mesophyll Cells of C4 Plants.- II. Bundle Sheath Cells of C4 Plants.- F. Energetics in C4 Metabolism.- G. Future Studies on C4 Metabolism with Cells and Protoplasts.- I. Transport Studies.- II. Screening for Inhibitors of C4 Photosynthesis.- References.- 8. The Flow of Carbon in Crassulacean Acid Metabolism (CAM).- A. Introduction.- B. Basic Phenomena of CAM.- C. The Metabolic Sequences of CAM.- I. The Flow of Carbon During the Night.- II. The Flow of Carbon During the Day.- D. Regulation of Carbon Flow in CAM.- E. Conclusions.- References.- 9. CAM: Rhythms of Enzyme Capacity and Activity as Adaptive Mechanisms.- A. Introduction.- B. Endogenous Versus Nonendogenous Rhythms: A Necessary Distinction.- C. Enzyme Capacity and Enzyme Activity: Two Distinct Levels of Control.- D. Rhythms Connected with CAM.- I. Components of the Malate Rhythm.- II. CO2 Uptake and CO2 Output.- III. PEP Carboxylase.- IV. Malate Dehydrogenase.- V. Malic Enzyme (NADP).- VI. Aspartate Aminotransferase.- VII. Enzymes of the Glycolytic Pathway.- VIII. Tricarboxylic Acid Cycle.- E. Working Hypothesis and Models.- I. Seasonal Adaptation.- II. Timing CAM.- References.- 10. ?13C as an Indicator of Carboxylation Reactions.- A. Introduction.- B. Carbon Isotope Fractionation and Its Measurement.- C. Variation in ?13C Values Between Plants.- I. Discrimination Caused by the Photosynthetic Pathway.- II. Variation in ?13C Values Between Plant Varieties and Species.- III. Variation in ?13C Values Within a Plant.- IV. Fractionation Associated with Carboxylation Enzymes.- V. Compartmental Organisation and Isotope Fractionation.- VI. Respiration.- D. Environmental Effects on the ?13C Value of Plants.- I. Temperature.- II. Carbon Dioxide Concentration.- III. Oxygen Concentration Effects on Discrimination.- IV. Light Level.- V. Availability of Water.- VI. Salinity and Carbon Isotope Fractionation.- E. Implications of Variation in ?13C Values Among Plant Species.- I. Natural Products.- II. Paleoecology.- III. Physiology — Plant, Animal, and Human.- F. Conclusions.- References.- II C. Factors Influencing CO2 Assimilation.- 11. Interactions Between Photosynthesis and Respiration in Higher Plants.- A. Introduction.- I. The Relevance of Photosynthetic and Respiratory Interactions.- B. Physiological Observations.- I. Plants with C3-Type Photosynthesis.- II. Plants with C4-Type Photosynthesis.- C. Biochemical Observations.- I. Plants with C3-Type Photosynthesis.- II. Plants with C4-Type Photosynthesis.- D. General Conclusions.- References.- 12. The Interaction of Respiration and Photosynthesis in Microalgae.- A. Introduction.- B. The Kok Effect.- C. Electron Transport Mechanisms for the Kok Effect.- I. General Considerations.- II. Prokaryotes.- III. Eukaryotes.- D. The Interaction of Oxygen with the Photosynthetic Electron Transport Chain.- E. Metabolically Mediated Control of Oxygen Uptake.- F. Synopsis.- References.- 13. Effect of Light Quality on Carbon Metabolism.- A. Introduction.- B. Principal Effects of Blue and Red Light on Carbon Metabolism.- C. Specific Features of Blue Light Action on Carbon Metabolism.- I. In the Absence of Photosynthesis.- II. In the Presence of Photosynthesis.- D. Direct Regulation of Certain Enzymes by Blue Light in Vitro and Its Possible Realization in Vivo.- E. Long-Term Effects of Light Quality on Biosyntheses and Chloroplast Organization.- F. Conclusion.- References.- 14. Photoassimilation of Organic Compounds.- A. Introduction.- B. Definitions.- C. Pathways and Products of Photometabolism.- D. Photo assimilation of Acetate.- E. Photo assimilation of Glucose.- References.- 15. Biochemical Basis of Ecological Adaptation.- A. Introduction.- B. Biochemical Variations in C3 Plants.- C. Biochemical Adaptation of CAM and C4 Plants.- I. Adaptive Value of C4 Metabolism.- D. Induced Variations in Carbon Fixation Pathways.- I. Effects of Age, CO2-Concentration, and Nitrogen Nutrition.- II. Effect of NaCl.- E. Concluding Remark.- References.- II D. Regulation and Properties of Enzymes of Photosynthetic Carbon Metabolism.- 16. Light-Dependent Changes of Stromal H+ and Mg2+ Concentrations Controlling CO2 Fixation.- A. Background.- B. Measurement of the pH in the Stroma and the Thylakoid Space of Intact Spinach Chloroplasts.- C. pH Dependence of CO2-Fixation.- D. Measurement of the Stromal Mg2+ Concentration in Intact Spinach Chloroplasts.- E. Mg2+ Dependence of CO2 Fixation.- F. Concluding Remarks.- References.- 17. Ribulose-1,5-Bisphosphate Carboxylase.- A. Fraction-1-Protein and RuBP Carboxylase.- B. Molecular Structure of RuBP Carboxylase.- C. Reaction Mechanism and Regulation.- D. RuBP Oxygenase.- E. Biosynthesis of RuBP Carboxylase.- References.- 18. Carbonic Anhydrase.- A. Introduction.- B. Characterization.- I. Histochemical and Other Detection.- II. Occurrence.- III. Location.- IV. Levels of Activity.- V. Isolation and Purification.- VI. Enzymic Parameters.- C. Function.- I. Chloroplast Envelope Membrane Permease.- II. Carbonic Anhydrase — RuBP Carboxylase Complex.- III. Proton Source, Buffering Capacity and Ionic Flux Regulation.- References.- 19. Enzymes of the Reductive Pentose Phosphate Cycle.- A. Introduction.- B. Characteristics of Regulatory Enzymes.- C. Activities and Location of Calvin Cycle Enzymes.- D. Glycerate-3-P Kinase.- E. Glyceraldehyde-3-P Dehydrogenase.- F. Triose-P Isomerase and Aldolase.- G. Fructosebisphosphatase and Sedoheptulosebisphosphatase.- H. Transketolase, Pentose-P Epimerase, and Pentose-P Isomerase.- I. Ribulose-5-P Kinase.- J. Concluding Remarks.- References.- 20. Enzymes of C4 Metabolism.- A. Introduction.- B. Isolation of Enzymes from Tissues of C4 Plants.- C. Carboxylation — PEP Carboxylase.- I. General Characteristics.- II. Physical Properties and Kinetics.- III. Regulation, Activation and Inhibition.- D. Formation of C4 Acids by Reduction and Transamination.- I. Reduction.- II. Transamination.- E. Decarboxylation.- I. NADP-Malic Enzyme (E.C.1.1.1.40).- II. NAD-Malic Enzyme (E.C.1.1.1.39).- III. PEP Carboxykinase (E.C.4.1.1.49).- F. Substrate Regeneration.- I. Pyruvate Pi Dikinase (E.C.2.7.9.1).- II. Alanine Aminotransferase (E.C.2.6.1.2).- G. Summary.- References.- 21. Enzymes of Crassulacean Acid Metabolism.- A. Introduction.- B. Enzymes of Starch Metabolism.- C. Glycolytic Enzymes.- D. Gluconeogenic Enzymes.- E. Carboxylating Enzymes.- I. The Formation of Malate.- II. The Photosynthetic Fixation of CO2.- F. Decarboxylating Enzymes.- I. The Decarboxylation of Malate.- II. The Decarboxylation of Oxaloacetate.- G. Respiratory Enzymes.- H. Conclusion.- References.- 22. Interaction Between Photochemistry and Activity of Enzymes.- A. Introduction.- B. Light-Mediated Modulation.- I. Occurrence.- II. Metabolic Significance.- III. Mechanism.- IV. Special Cases.- C. Dark Modulation.- D. Thylakoid-Generated Effectors.- I. pH.- II. Mg2+.- III. Energy Charge.- E. Conclusion.- References.- II E. Metabolism of Primary Products of Photosynthesis.- 23. Metabolism of Starch in Leaves.- A. Introduction.- B. Starch Biosynthesis.- I. Reactions Involved in Starch Biosynthesis.- II. The Predominant Pathway of Starch Synthesis.- III. Regulation of Starch Biosynthesis.- IV. Properties of the ADPglucose: 1,4-?-D-glucan 4-? Glucosyltransferase.- V. ?-1,4-Glucan: ?-1,4-Glucan 6-Glycosyl Transferase (Branching or Q Enzyme).- VI. Remaining Problems in Starch Synthesis.- C. Starch Degradation.- I. Reactions Involved in Starch Degradation.- II. Degradation of Intact Granules in Vitro.- III. Starch Degradation in Vivo: Germinating Seeds.- IV. Starch Degradation in Vivo: Leaves.- References.- 24. The Enzymology of Sucrose Synthesis in Leaves.- A. Introduction.- B. Physiological Relationships of Sucrose in Leaves.- C. Enzymology.- I. Sucrose Phosphate Synthetase E.C.2.4.1.14 and Sucrose Synthetase E.C.2.4.1.13.- II. Sucrose Phosphatase (E.C.3.1.3.24).- III. UDPglucose Pyrophosphorylase (E.C.2.7.7.9).- IV. Sucrose Phosphorylase (E.C.2.4.1.7).- V. Invertase (E.C.3.2.1.26).- VI. Enzyme Control Mechanisms.- D. Intracellular and Intercellular Site of Sucrose Synthesis in Leaves.- I. Chloroplast or Cytoplasm?.- II. Intercellular Localization of Sucrose Synthesis in C4 Plants.- III. Intercellular Distribution Between Cells Containing Chlorophyll and Vascular Tissue.- References.- II F. Glycolic Acid and Photorespiration.- 25. Glycolate Synthesis.- A. Introduction: Glycolate Formation, Photorespiration and the Warburg Effect.- B. Environmental Factors Affecting Glycolate Synthesis.- C. Mechanisms of Glycolate Formation.- I. Reductive Glycolate Formation.- II. Oxidative Glycolate Synthesis.- D. Photosynthetic Glycolate Formation in Vivo; Which Reaction Predominates?.- I. Glycolate Synthesis by C3 Plants.- II. Glycolate Formation by C4 Plants.- E. Conclusion: The Inhibition of Glycolate Formation by Some Common Metabolites — an Open Question.- References.- 26. Glycolate Metabolism by Higher Plants and Algae.- A. Introduction.- B. Glycolate Biosynthesis.- I. Properties of Ribulose-P2 Carboxylase/Oxygenase for Phosphoglycolate Biosynthesis.- II. Phosphoglycolate Phosphatase and Phosphoglycerate Phosphatase.- C. Glycolate Pathway.- I. Pathways in Peroxisomes.- II. Mitochondrial Interconversion of Glycine and Serine.- D. O2 and CO2 Exchange and Energy Balance.- I. Sites of O2 Uptake and CO2 Release in the Glycolate Pathway.- II. O2 Uptake During Photosynthesis.- III. Energy Balance.- E. Leaf Peroxisomal Membrane and Transport.- F. Glycerate and Sucrose from Glycolate.- G. The Glycolate Pathway in Algae.- I. Introduction.- II. Glycolate Excretion.- III. Glycolate Dehydrogenase.- IV. Glycerate-Serine Pathway in Algae.- References.- 27. Photorespiration: Studies with Whole Tissues.- A. Discovery of Photorespiration.- B. Assays of Photorespiration in Leaves.- I. Post-Illumination CO2 Outburst.- II. Inhibition of Net CO2 Assimilation by Oxygen.- III. CO2 and 14CO2 Efflux in CO2-Free Air.- IV. Short-Time Uptake of 14CO2 and 12CO2.- V. The Magnitude of Photorespiration in Leaves.- C. Photorespiration in Algae and Submerged Aquatic Plants.- D. Photorespiration in Callus, Isolated Plant Cells, and Protoplasts.- E. The Control of Photorespiration.- I. The Energetics and Possible Origins of Photorespiration.- II. Biochemical Inhibition of Glycolate Oxidation.- III. Biochemical Inhibition of Glycolate Synthesis.- IV. The Metabolic Regulation of Photorespiration.- References.- 28. Photorespiration: Comparison Between C3 and C4 Plants.- A. Introduction.- B. Terminology and Perception.- C. Measurement of Photorespiration.- D. Characteristics of Photorespiration in C3 Plants.- I. Rates of Photorespiration.- II. The Post-Illumination Burst.- III. Compensation Point.- IV. Effect of CO2 Concentration.- V. Effect of O2.- VI. Effect of Temperature.- VII. Interaction of Oxygen, Carbon Dioxide, and Temperature.- VIII. Effect of Light Intensity.- IX. The Glycolate Pathway.- E. Photo respiration in C4 Plants.- I. Photorespiration as CO2 Evolution.- II. Photorespiration as Oxygen Uptake.- III. Photorespiration in C4 Plants — Indirect Evidence.- IV. Evidence Against Photorespiration in C4 Plants.- F. Concluding Remarks.- References.- III. Ferredoxin-Linked Reactions.- 1. Transhydrogenase.- A. Introduction and Definitions.- B. Soluble Flavoproteins with Transhydrogenase Activity.- I. Bacterial Enzymes.- II. Ferredoxin-NAD(P)+ Reductases.- C. Membrane-Bound (Particulate) Transhydrogenases.- I. Mitochondrial and Bacterial Transhydrogenases; General Aspects.- II. Transhydrogenase of Photosynthetic Bacteria.- References.- 2. Oxygen Activation and Superoxide Dismutase in Chloroplasts.- A. Introduction.- B. Principles of Oxygen Activation.- C. Superoxide Anion and Superoxide Dismutase.- I. Dismutation of the Superoxide Anion (O.-2); Superoxide Dismutase in Plants.- II. Superoxide Dismutase in Chloroplasts.- III. Monovalent Oxygen Reduction in Chloroplasts.- D. Determination of the Products of Oxygen Reduction.- E. Possible Functions of Reduced Oxygen Species in Chloroplasts.- I. Desaturation of Fatty Acids.- II. Hydroxylation of Aromatic Compounds.- III. Photorespiration.- IV. Ethylene Formation.- F. Conclusions.- References.- 3. Ferredoxin-Linked Carbon Dioxide Fixation in Photosynthetic Bacteria.- A. Introduction.- B. Ferredoxin-Linked Carboxylation Reactions.- I. Synthesis of Pyruvate.- II. Synthesis of ?-Ketoglutarate.- III. Synthesis of ?-Ketobutyrate.- IV. Synthesis of Phenylpyruvate.- V. Synthesis of ?-Ketoisovalerate.- VI. Synthesis of Formate.- C. The Reductive Carboxylic Acid Cycle.- D. Concluding Remarks.- References.- 4. Reduction of Nitrate and Nitrite.- A. Introduction.- B. Reduction of Nitrate to Nitrite.- I. Assimilatory Nitrate Reductase of Eukaryotes.- II. Assimilatory Nitrate Reduction in Prokaryotes.- C. Reduction of Nitrite to Ammonia.- I. Nitrite Reductase of Photosynthetic Cells.- II. Nitrite Reductase of Nonphotosynthetic Cells.- D. Control of Nitrate Reduction.- I. Synthesis and Degradation of Enzymes.- II. Utilization of Nitrate.- III. Reversible Inactivation of Nitrate Reductase.- IV. Localization of Enzymes and Effect of Light and Carbohydrate on Nitrate Utilization.- V. Conclusions.- References.- 5. Photosynthetic Ammonia Assimilation.- A. Introduction.- B. Photosynthetic Ammonia Assimilation in Intact Organisms.- C. Localization of Enzymes Involved in Ammonia Assimilation.- I. Glutamate Dehydrogenase.- II. Glutamine Synthetase.- III. Glutamate Synthase (GOGAT).- D. Photosynthetic Ammonia Assimilation in Isolated Intact Chloroplasts.- E. Photorespiratory Ammonia Evolution and Reassimilation.- F. Conclusions.- References.- 6. N2 Fixation and Photosynthesis in Microorganisms.- A. Introduction.- B. Distribution of Nitrogenase Among Photosynthetic Prokaryotes.- C. Oxygen Sensitivity and Protection of Algal Nitrogenase.- D. Requirements for an Active Nitrogenase.- E. The Provision of Reductant and ATP in Photosynthetic Prokaryotes.- I. Electron Donation.- II. The Production of ATP.- F. The Nitrogen-Fixing System of Heterocysts of Anabaena cylindrica.- G. Nitrogenase and Its Possible Regulation by Glutamine Synthetase.- References.- 7. Symbiotic N2 Fixation and Its Relationship to Photosynthetic Carbon Fixation in Higher Plants.- A. Introduction.- B. Relationship of N2 Fixation to Carbon Assimilation.- I. Nitrogenase.- II. ATP and Reductant.- III. Ammonia Assimilation.- IV. Photosynthate as the Limiting Factor.- V. Translocation and Partitioning of Nitrogen and Carbon Assimilates.- References.- 8. Photosynthetic Assimilation of Sulfur Compounds.- A. Introduction.- B. Observations with Whole Organisms.- C. Observations with Isolated Organelles.- D. Cell-Free Systems.- I. Sulfate Activation and Degradation of Active Sulfate.- II. Transfer of Sulfate from Sulfonucleotides for Further Reduction.- III. Reduction to the Level of Sulfide.- IV. Biosynthesis of Cysteine.- E. Regulation of Assimilatory Sulfate Reduction in Photosynthetic Organisms.- References.- 9. Hydrogen Metabolism.- A. Introduction.- B. Hydrogenase.- I. Occurrence of Hydrogenase in Photosynthetic Cells.- II. Adaptation and Deadaptation.- III. Cell-Free Preparations of Hydrogenase.- C. Evolution of H2.- I. Dark Evolution of H2.- II. H2 Photoevolution.- III. H2 Evolution by Blue-Green Algae.- D. Consumption of H2.- I. Dark Absorption of H2.- II. Photoreduction.- References.- Author Index.