Structure and Function of Chloroplasts

It is now about 100 years since the chloroplast has been recognized as the site of photosynthesis in plant cells. The last 20 years have seen a striking increase in interest in the structure and function of the chloroplast. Hastened on by powerful new tools such as the electron microscope and the newer methods of isolation and analysis of chloroplasts, there is presently considerable experimental work on the properties of this organelle. In such a rapidly moving field and one which is reviewed systematically is various Annual Reviews, it is not possible to present a detailed critique of the prolific literature in a book of reasonable size. Rather the decision was made to sacrifice complete coverage of the field and to indicate general areas of investigation. In organization, problems here dealt with, are those concerned with the electron microscopy of chloroplast structure, development and conformation, genetic control of chloroplast development, characterization of some of the major components of the chloroplast and the biochemical properties of the chloroplast including the for­ mation of adenosine triphosphate and reduced pyridine nucleotide and the assim­ ilation of carbon dioxide into carbohydrate with subsequent conversion to second­ ary products. A historical outline on the general subject "Photosynthesis and the Chloroplast" has been included to place into proper perspective the rapid developments in the several areas covered in the book. I am particularly indebted to Dr. Roy E.

Historical Outline.- Photosynthesis and the Chloroplast.- The Ultrastructure of Plastids.- A. Introduction.- B. Proplastids.- 1. The Prolamellar Body.- 2. Thylakoid Formation.- 3. Constituents of the Proplastids.- 4. Ribosomes.- 5. Nucleic Acid Fibrils.- 6. Microfilaments.- 7. Plastoglobuli.- 8. Stromacenter.- 9. Phytoferritin.- C. Amyloplasts, Proteinoplasts, and Elaioplasts.- D. Chloroplasts.- 1. Architecture of the Lamellar System.- 2. Ultrastructure of the Thylakoid Membrane.- E. Chromoplasts.- 1. The Globular Type.- 2. The Tubular Type.- 3. The Crystalline Type.- F. Literature.- Light-Induced Chloroplast Contraction and Movement.- A. Introduction.- B. Changes in Chloroplast Shape.- C. Light-Induced Chloroplast Movements.- 1. The Photoreceptor Problem.- a) Action Spectra of Chloroplast Movements.- b) The Location of the Photoreceptor.- c) Orientation of the Photoreceptor Molecules.- 2. Experiments in Mougeotia spec, a Green Alga.- a) Temperature Experiments in Mougeotia.- b) Localization of the Red-Far Red System in Mougeotia.- 3. Different Models for the Mechanism of Chloroplast Movement.- a) The Peristromium Hypothesis.- b) The Surface Tension Hypothesis.- c) The Electrokinetic Hypothesis.- d) The Hypothesis of Pulling Fibers.- e) Recent Hypotheses.- D. Literature.- Plastid Inheritance and Mutations.- A. Introduction.- B. Inheritance of Chloroplast Mutations.- 1. Gene Mutations.- 2. Plastome Mutations.- a) Maternal Inheritance.- b) Biparental Inheritance.- c) Gene-Induced Plastome Mutations.- d) Humulus japonicus.- e) Oenothera.- f) Euglena.- C. Nature of the Plastome.- 1. The Genetic Autonomy of Plastids.- 2. The Significance of Plastid DNA.- 3. The Origin of Plastids.- D. The Genetic Control of Chloroplast Development and Function.- 1. Biochemistry of Chloroplast Mutants.- 2. Mutants Affected in Photosynthetic Enzymes.- 3. Chlorophyll-Deficient Mutants.- 4. Carotenoid-Deficient Mutants.- 5. Chloroplast Mutants Defective in General Metabolism.- 6. Chloroplast Mutants with Unidentified Biochemical Defects.- a) Gene Mutations.- b) Plastome Mutations.- E. Concluding Remarks.- F. Literature.- Nucleic Acids and Information Processing in Chloroplasts.- A. Introduction.- B. Information Storage.- 1. In situ Studies.- 2. Studies on Extracted DNA.- 3. Preparation and Characterization.- 4. Physical Properties of Plant DNAs.- a) Higher Plants.- b) Algal Plastid DNAs.- 5. Coding Capacity of Chloroplast DNA.- 6. Sequence Homology of Plastid DNA.- C. Information Replication.- D. Information Transcription.- 1. Plastid RNAs.- 2. RNA Synthesis in Plastids.- 3. Affinities of Plastid rRNA.- E. Information Translation.- 1. Components of the Protein Synthetic System.- 2. Protein Synthesis in vitro.- 3. Identification of the Products of Plastid Protein Synthesis by Inhibitor Studies.- F. Information Processing in Acetabularia Plastids.- 1. Information Storage.- 2. Information Replication.- 3. Information Transcription.- 4. Ribosomal RNAs.- 5. Ribosomes.- 6. RNA Synthesis in Isolated Plastids.- 7. Information Translation.- 8. Conclusions.- G. Literature.- Lipids of Chloroplasts.- A. Phospholipids of Chloroplasts.- B. Glycolipids of Chloroplasts.- C. ?-Linolenic Esters in Lipids of Oxygen-Producing Chloroplasts.- D. The Plant Sulfolipid.- E. Deacylation of Chloroplast Lipids.- 1. Galactolipase.- 2. Sulfolipase.- 3. Phospholipases.- F. “Osrrnophilic” Lipid Globules of Chloroplasts.- G. Assembly of Chloroplast Lipoprotein.- H. Reconstitution of Chloroplast Membrane Lipoprotein.- I. Literature.- Biochemistry of Photophosphorylation.- A. Historical Introduction.- B. Electron Flow Patterns.- C. Coupling of Phosphorylation to Electron Flow.- D. Phosphorylation Inhibitors.- E. Partial Reactions Requiring a High Energy State.- 1. Adenosine Triphosphatase.- 2. ATP-Pi Exchange.- 3. Two-Stage Photophosphorylation.- 4. Light-Induced Proton Gradient.- 5. ATP Formation by an Acid-Base Transition.- 6. Light-Induced Conformational Changes.- F. Photophosphorylation in vivo.- G. Literature.- Carbohydrate Metabolism by Chloroplasts.- A. Isolation of Chloroplasts.- 1. Aqueous Methods.- 2. Non-Aqueous Methods.- B. Compounds Formed during Photosynthetic CO2 Assimilation and Their Intramolecular Labeling Patterns.- 1. Spinach and Pea.- 2. Maize and Related Plants.- C. Enzymes Catalyzing the Reduction of CO2 to Carbohydrate.- 1. Plants Utilizing the Cycle of Calvin.- 2. Plants Utilizing the C4-Dicarboxylic Acid Pathway.- 3. Carboxylating Reactions.- D. Stoichiometry of Photosynthesis Measured in the Chloroplast.- E. Kinetics of CO2 Fixation.- 1. Induction Phenomenon.- 2. CO2 Dependent and Light-Dark Transients.- F. Factors Controlling the Reduction of CO2 to Carbohydrate.- 1. Temperature.- 2. pH.- 3. Enzyme Activation.- 4. Oxygen.- 5. Transport of Metabolites.- a) Intermediates of the Photosynthetic Carbon Reduction Cycle.- b) Glycolate.- 6. Orthophosphate and Pyrophosphate.- 7. Intermediates of the Photosynthetic Carbon Reduction Cycle.- G. Literature.- Biosynthesis by Chloroplasts.- A. Proteins.- 1. The Presence of DNA and RNA.- 2. Energy.- 3. Amino Acid-Activating Enzymes.- 4. Amino Acids.- 5. Overall Protein Synthesis by Chloroplasts.- B. Lipids.- 1. General.- 2. Fatty Acids.- a) General.- b) Specific Fatty Acids.- 3. Complete Lipids.- a) Phospholipids.- b) Galactosyl Glycerides.- c) Plant Sulpholipid.- C. Chloroplast Pigments.- 1. General.- 2. Chlorophylls.- a) ?-Aminolevulinic Acid (ALA) Synthesis.- b) Porphobilinogen (PBG) Synthesis.- c) Formation of Porphyrinogens.- d) Conversion of Urogen III into Protoporphyrin.- e) Chelation of Protoporphyrin.- f) Conversion of Mg Protoporphyrin into Chlorophyll a.- g) Chlorophyll Synthesis in Relation to Plastid Development.- h) Timing of Chlorophyll Biosynthesis.- i) Effect of Iron on Chlorophyll Synthesis.- j) Chlorophyll Synthesis in the Dark.- 3. Phycobilins.- 4. Carotenoids.- a) Formation of Carotenes.- b) Formation of Xanthophylls.- c) Stereospecificity of Carotenoid Biosynthesis.- d) Mechanism of Phytoene Formation.- e) Mechanism of Ring Formation.- f) Mechanism of Xanthophyll Formation.- g) Effect of Light.- h) Genetic Control of Carotenoid Synthesis in Chloroplasts.- i) Evidence for Formation of Carotenoids in Chloroplasts.- D. Chloroplast Quinones.- E. Polyprenols.- F. Sterols.- G. Regulation of Terpenoid Synthesis.- 1. In Developing Chloroplasts.- 2. In Mature Chloroplasts.- 3. Loss of Regulation during Changes of Chloroplasts into Chromoplasts..- H. Literature.