Plant Carbohydrates I

I. Monomeric and Oligomeric Sugars and Sugar Derivatives - Occurrence, Metabolism, Function.- 1 Aldo (and Keto) Hexoses and Uronic Acids.- 1 Introduction.- 1.1 Historical.- 1.2 Sugar Nucleotides and Carbohydrate Interconversions in Plants.- 1.3 Sugar Nucleotides Isolated from Plants to Date.- 2 Phosphorylation of Free Sugars.- 2.1 Hexokinase.- 2.2 d-Galactokinase and L-Arabinokinase.- 2.3 d-Glucuronokinase.- 2.4 d-Galacturonokinase.- 3 Formation of Nucleotide Sugars (Pyrophosphorylases).- 3.1 UDP-d-Glucose Pyrophosphorylase.- 3.2 ADP-d-Glucose Pyrophosphorylase.- 3.3 GDP-d-Glucose Pyrophosphorylase.- 3.4 TDP-d-Glucose Pyrophosphorylase.- 3.5 Utilization of ?-d-Galactopyranosyl Phosphate.- 3.6 GDP-d-Mannose Pyrophosphorylase.- 3.7 UDP-N-Acetyl-d-Glucosamine Pyrophosphorylase.- 3.8 ADP-N-Acetyl-d-Glucosamine Pyrophosphorylase.- 3.9 GDP-l-Fucose Pyrophosphorylase.- 3.10 UDP-d-Glucuronate Pyrophosphorylase.- 3.11 UDP-d-Galacturonate Pyrophosphorylase.- 3.12 Nucleoside Diphosphate Pentose Pyrophosphorylases.- 3.13 Other Nucleotide Sugar Pyrophosphorylase Activities.- 3.14 Other Transglycosylation Reactions Responsible for the Formation of Nucleotide Sugars.- 3.15 Degradation of Nucleotide Sugars.- 3.15.1 ADP-d-Glucose Phosphorylase.- 3.15.2 Hydrolysis of Nucleotide Sugars by Phosphodiesterase.- 4 Nucleotide Sugar Epimerases.- 4.1 UDP-d-Glucose-4-Epimerase.- 4.2 UDP-d-Xylose-4-Epimerase.- 4.2.1 Possible Origin of L-Arabinofuranosyl Moieties.- 4.3 UDP-d-Glucuronate-4-Epimerase.- 4.4 Biosynthesis of l-Galactose in Plants (GDP-D-Mannose-3,5-Epimerase).- 4.5 GDP-d-Glucose-2-Epimerase.- 5 Biosynthesis of Deoxysugars in Plants.- 5.1 l-Rhamnose and L-Fucose.- 5.2 UDP-Digitoxose.- 6 Biosynthesis of Uronic Acid in Plants (d-Glucuronic Acid).- 6.1 UDP-d-Glucose Dehydrogenase.- 7 De Novo Synthesis of UDP-d-Xylose; UDP-d-Glucuronate Decarboxylase.- 7.1 UDP-d-Glucuronate Decarboxylase.- 8 Miscellaneous Topics (Not Treated Above).- 8.1 Nucleotide Sugars Involving d-Fructose and d-Ribose.- 8.1.1 UDP-d-Fructose.- 8.1.2 ADP-d-Ribose (5).- 8.2 Control of Nucleotide Sugar Synthesis and Utilization.- 9 Possible Evolutionary Significance of Carbohydrate Interconversion Pathways.- References.- 2 Polyhydroxy Acids: Relation to Hexose Phosphate Metabolism.- 1 Introduction.- 2 Overview of the Role of Hexoses, Pentoses and Polyhydroxy Acids in Metabolic Systems of Plants.- 3 Reactions and Functions of the Oxidative Pentose Phosphate Pathway, and Properties of Glucose 6-Phosphate and 6-Phosphogluconate Dehydrogenases.- 4 Glucose 6-Phosphate-myo-Inositol Glucuronate Pathway and Metabolism of Phytic Acid.- 5 Biosynthesis, Metabolic Reactions and Proposed Metabolic Functions of L-Ascorbate.- 6 l-(+)-Tartaric Acid and Oxalic Acid Metabolism.- 7 Concluding Remarks.- References.- 3 Amino Sugars - Plants and Fungi.- 1 Introduction.- 2 Nomenclature.- 3 Methods of Detection.- 4 Occurrence.- 4.1 Amino Sugars in Fungal Cell Walls.- 4.2 Mannans.- 4.3 Amino Sugars in Algal Cell Walls.- 4.4 Glycoproteins.- 4.4.1 Fungi.- 4.4.2 Higher Plants.- 4.4.3 Membrane Glycoproteins in Higher Plants.- 5 Glycolipids.- 5.1 Lipid Intermediates in Glycoprotein Biosynthesis.- 5.2 Glycosphingolipids.- 6 Amino Sugar Biosynthesis.- 6.1 Glucosamine 6-Phosphate.- 6.1.1 Hexokinases.- 6.2 Formation of N-Acetylglucosamine-6-Phosphate.- 6.3 Conversion of GlcNAc-6-Phosphate to GlcNAc-1-Phosphate.- 6.4 Amino Sugar Nucleotides.- 7 Galactosamine.- 8 Glycosidases.- 8.1 Higher Plants.- 8.2 Fungi.- References.- 4 Branched-Chain Sugars.- 1 Introduction.- 2 Branched-Chain Monosaccharides of Green Plants.- 2.1 d-Hamamelose.- 2.1.1 Elucidation of the Structure.- 2.1.2 Occurrence of Free d-Hamamelose.- 2.1.3 Biosynthesis of d-Hamamelose.- 2.1.4 Natural Derivatives of d-Hamamelose.- 2.1.5 Biological Degradation of d-Hamamelose.- 2.2 d-Apiose (3-C-Hydroxymethyl)-d-Glycero-Aldotetrose).- 2.2.1 Elucidation of the Structure.- 2.2.2 d-Apio d-Furanose as Glycosidic Component of Plant Cell Wall Polysaccharides and of Phenolic Plant Constituents.- 2.2.3 Biosynthesis of UDP-d-Apiose.- 2.2.4 Transfer of the d-Apiosyl-Residue.- 2.2.5 Metabolism of d-Apiose.- 3 Branched-Chain Monosaccharides of Microorganisms.- 3.1 Methyl-Branched Monosaccharides.- 3.1.1 CDP-l-Vinelose (Cytidine-6-Deoxy-3-C-(Methyl)-2-O-Methyl-l-Talose).- 3.1.2 l-Noviose (6-Deoxy-3-O-Carbonyl-5-C-Methyl-4-O-Methyl-l-Lyxohexose).- 3.1.3 l-Mycarose (2,6-Dideoxy-3-C-Methyl-l-Ribohexose).- 3.1.4 l-Cladinose (2,6-Dideoxy-3-C-Methyl-3-O-Methyl-l-Ribohexose.- 3.2 C-(Hydroxyethyl)-and C-(Oxoethyl)-Branched Monosaccharides.- 3.2.1 d-Aldgarose.- 3.2.2 The Branched-Chain Sugars of the Quinocycline Antibiotics.- 3.3 C-Hydroxymethyl-and C-Formyl-Branched Monosaccharides: The Sugars of the l-Streptose Family.- 4 Conclusion: Physiological Problems Originating from the Branched Carbon Skeleton.- References.- 5 Sugar Alcohols.- 1 Introduction.- 1.1 General Comments on Polyols.- 1.2 Summary of Earlier Reviews.- 2 Occurrence.- 2.1 General Information.- 2.2 Mannitol.- 2.3 Sorbitol.- 2.4 Other Hexitols.- 2.5 The Tetritols and Pentitols.- 2.6 The Heptitols and Octitols.- 2.7 Other Polyols.- 2.8 The Heterosides.- 2.9 Phosphate Esters.- 3 Methods of Study.- 3.1 General.- 3.2 Preparations of Extracts.- 3.3 Fractionation of the Extract.- 3.4 Use of Chromatographic and Electrophoretic Procedures.- 3.5 Methods of Estimation.- 4 Metabolism of Polyols.- 4.1 General.- 4.2 Photosynthetic Production of Polyols.- 4.3 Metabolism of Polyols and Sugars.- 4.4 Enzymes of Polyol Metabolism.- 4.5 Uptake of Polyols.- 5 Physiology and Role in Nature.- 5.1 Sugar Interconversion.- 5.2 Polyols as Redox Agents.- 5.3 Osmoregulation.- 5.4 Cryoprotection.- 5.5 Transport and Storage.- 6 Future Directions of Research.- 7 Conclusion.- References.- 6 Cyclitols.- 1 Introduction.- 2 Nomenclature and Stereochemistry.- 3 Occurrence.- 4 Formation.- 5 Metabolic Processes.- 6 Physiological Roles.- 7 Concluding Remarks.- References.- 7 Sucrose and Other Disaccharides.- 1 Introduction.- 2 Sucrose.- 2.1 Introduction.- 2.2 Enzymes of Sucrose Biosynthesis.- 2.2.1 General.- 2.2.2 Sucrose Synthase.- 2.2.3 Sucrose Phosphate Synthase.- 2.2.4 Sucrose Phosphatase.- 2.2.5 Assay of Sucrose-Synthesizing Enzymes.- 2.3 Sucrose Hydrolases (Invertases).- 2.3.1 General.- 2.3.2 The Enzymes.- 2.3.3 Level and Location of Invertase in Tissues.- 2.3.4 Invertase Inhibitors.- 2.3.5 Sucrose and the Synthesis of ?-Fructofuranans.- 2.4 Subcellular Site of Sucrose Synthesis.- 2.4.1 The Compartment.- 2.4.2 Carbon Fluxes in Leaves.- 2.4.3 Carbon Fluxes in Storage Tissues.- 2.5 Source of Carbon for Sucrose Synthesis.- 2.5.1 Gluconeogenesis from Phosphoglycerate.- 2.5.2 Photorespiration Intermediates.- 2.5.3 Pyruvate and Related Intermediates.- 2.5.4 Utilization of Storage Reserves.- 2.5.5 Metabolic Controls.- 2.5.6 13C-Discrimination.- 2.6 Sucrose Translocation.- 2.7 Intracellular Compartmentation of Sucrose.- 2.8 Sucrose-Starch Transformation.- 2.8.1 General Considerations.- 2.8.2 Photosynthetic Tissues.- 2.8.3 Rice.- 2.8.4 Maize.- 2.8.5 Wheat, Barley and Sorghum.- 2.8.6 Potato Tubers.- 2.9 Sucrose as a Source of Nucleoside Diphosphate Glycosyls.- 2.10 Utilization of Exogenous Sucrose.- 2.11 Sucrose and Environmental Stress.- 2.11.1 Water Stress.- 2.11.2 Illumination and Irradiance.- 2.11.3 Frost.- 2.11.4 High Temperature.- 2.11.5 NH4+.- 2.11.6 Metal Toxicity.- 2.11.7 Potassium Deficiency.- 2.11.8 CO2 and SO2.- 2.11.9 Salt and Ion Concentration.- 2.11.10 Infection and Symbiosis.- 2.11.11 Low O2.- 2.11.12 Boron.- 3 ?,?-Trehalose (O-?-d-Glucopyranosyl-?-O-d-Glucopyranoside).- 3.1 Occurrence.- 3.2 Metabolism.- 3.2.1 Synthesis.- 3.2.2 Degradation.- 3.2.3 Metabolic Pattern.- 4 Other Nonreducing Disaccharides and Related Glycosides.- 4.1 Disaccharides.- 4.2 Monoglycosides of Polyhydroxy Alcohols and Acids.- 4.2.1 Monoglycoside-Alditols.- 4.2.2 Glycosyl Glyceric Acids.- 4.2.3 Glycoside-Cyclitols.- 5 Maltose.- 5.1 General.- 5.2 Occurrence.- 5.3 Mechanism of Formation.- 5.4 Mechanism of Utilization.- 5.5 Patterns of Metabolism in Leaves.- 5.6 Utilization of Maltose as an External Source of Carbohydrate.- 6 Reducing Disaccharides.- 6.1 Introduction.- 6.2 Disaccharides from Storage Oligosaccharides.- 6.2.1 Melibiose.- 6.2.2 Isomelibiose (Umbelliferobiose).- 6.2.3 Planteobiose.- 6.2.4 Isolychnobiose.- 6.2.5 Turanose.- 6.2.6 Gentiobiose.- 6.3 Disaccharides as Products of Polysaccharide Degradation.- 6.3.1 ?-Glucosides.- 6.3.2 Mannosides.- 6.3.3 Galactosides.- 6.3.4 Lactose.- 6.3.5 Arabinosides.- 6.3.6 Xylosides.- 6.3.7 Fructobioses.- 6.3.8 Hexuronides.- 6.3.9 Chitobiose.- 6.4 Reducing Disaccharides Produced by Glycoside Hydrolase-Catalyzed Transglycosylations.- 6.4.1 d-Glucosides.- 6.4.2 d-Galactosides.- 6.4.3 ?-Fructofuranosides.- 6.5 Disaccharides in Plant Glycosides.- References.- 8 Oligosaccharides Based on Sucrose (Sucrosyl Oligosaccharides).- 1 Introduction.- 2 Extraction, Isolation and Identification of Sucrosyl Oligosaccharides.- 3 Occurrence of Sucrosyl Oligosaccharides and Their Distribution in Higher Plants.- 3.1 Raffinose Series.- 3.2 Lolium Trisaccharide.- 3.3 Umbelliferose.- 3.4 Lychnose and Isolychnose Series.- 3.5 Planteose Series.- 3.6 Kestoses (Fructosylsucroses) Series (Fructan).- 3.7 Gentianose.- 4 Biosynthesis of Sucrosyl Oligosaccharides.- 4.1 The Biosynthesis of the Raffinose Series.- 4.2 Biosynthesis of Lolium Trisaccharide.- 4.3 Biosynthesis of Umbelliferose.- 4.4 Biosynthesis of the Lychnose and Isolychnose Series.- 4.5 Biosynthesis of the Planteose Series.- 4.6 Biosynthesis of the Kestoses (Fructosylsucroses) Series (Fructan).- 4.7 Biosynthesis of Gentianose.- 5 Degradation of Sucrosyl Oligosaccharides.- 6 Function of Sucrosyl Oligosaccharides.- 6.1 Storage.- 6.2 Translocation.- 6.3 Frosthardiness.- 7 Concluding Remarks.- References.- 9 Glycosylation of Heterosides (Glycosides).- 1 Introduction.- 2 O-Glycosides.- 2.1 Phenolic Glycosides.- 2.1.1 Simple Phenolic Glycosides.- 2.1.2 Flavonoid Glycosides.- 2.1.3 Coumarin Glycosides.- 2.1.4 Anthraquinone Glycosides.- 2.2 Glycosides of Terpenoids.- 2.2.1 Monoterpene Glycosides.- 2.2.2 Steryl Glycosides.- 2.2.3 Cardiac (Digitalis) Glycosides.- 2.2.4 Glycosylated Steroid Alkaloids.- 3 C-Glycosides.- 4 Conclusion.- References.- II. Macromolecular Carbohydrates - Occurrence, Metabolism, Function.- 10 Biosynthesis of Starch and Its Regulation.- 1 Pertinent Enzymatic Reactions.- 1.1 Suggestive Evidence for the Major Route to Starch Formation.- 1.2 Sucrose Conversion to Starch in Reserve Tissues.- 2 Regulation of Starch Synthesis.- 2.1 General Considerations.- 2.2 Regulation of Leaf and Algal ADPglucose Pyrophosphorylases by 3-P-Glycerate and Orthophosphate.- 2.3 Are the Allosteric Phenomena Operative in Vivo?.- 3 Properties of the Starch Biosynthetic Enzymes.- 3.1 ADPglucose Pyrophosphorylase.- 3.1.1 Enzyme from Higher Plants, Green Algae and Blue-Green Bacteria.- 3.1.2 Native and Subunit Molecular Weight of ADPglucose Pyrophosphorylase.- 3.1.3 ADPglucose Pyrophosphorylases of Nonphotosynthetic Plant Tissues.- 3.2 Properties of Starch Synthase (ADPglucose: (1 ? 4)-?-d-Glucan 4-?- Glucosyltransferase).- 3.2.1 Starch Bound and Soluble Starch Synthases.- 3.2.2. Requirements for Activity.- 3.2.3 Multiple Forms of Soluble Starch Synthase.- 4 Branching (Q) Enzyme ((1?4)-?-Glucan 6-Glycosyl Transferase).- 4.1 Mechanism of Action.- 4.2 Multiple Forms of Plant Branching Enzymes.- 4.3 A Possible Function for the Multiple Forms of Starch Synthases and Branching Enzymes.- References.- 11 Reserve Polysaccharides Other Than Starch in Higher Plants.- 1 Introduction.- 2 Cell Wall Storage Polysaccharides in Seeds.- 2.1 Occurrence and Classification.- 2.2 The Mannan Group.- 2.2.1 "Pure" Mannans.- 2.2.2 Glucomannans.- 2.2.3 Galactomannans.- 2.2.4 Other Mannans.- 2.3 The Xyloglucans.- 2.3.1 Distribution.- 2.3.2 Structures.- 2.3.3 Metabolism.- 2.4 The Galactans.- 2.5 Others.- 3 Nonstarch Storage Polysaccharides of Vegetative Tissues.- 3.1 Occurrence and Classification.- 3.2 The Fructan Group.- 3.2.1 Fructans of the Dicotyledons.- 3.2.2 Fructans of the Monocotyledons.- 3.3 The Mannan Group.- 3.3.1 Occurrence and Chemistry.- 3.3.2 Cytology, Deposition, and Mobilization.- 3.4 Other Polysaccharides with a Possible Reserve Function.- 4 Biological Functions.- 4.1 Cell Wall Storage Polysaccharides in Seeds.- 4.2 Nonstarch Storage Polysaccharides in Vegetative Tissue.- References.- 12 Reserve Carbohydrates of Algae, Fungi, and Lichens.- 1 Introduction.- 1.1 Starch and Glycogen-Type Reserve Polysaccharides.- 1.2 (l-3)-?-d-Glucans.- 1.3 Other Types of Reserve Carbohydrate.- 2 Reserve Carbohydrates of Marine Algae.- 2.1 ?-d-Glucans.- 2.1.1 Floridean Starch.- 2.1.2 Starches.- 2.2 ?-d-Glucans.- 2.2.1 Laminarin.- 2.2.2 Eisenan.- 2.3 Fructans.- 2.4 Xylans.- 2.5 Other Polysaccharides.- 3 Reserve Carbohydrates of Freshwater Algae.- 3.1 ?-d-Glucans.- 3.1.1 Starches.- 3.1.2 Amylopectin and Phytoglycogen Type.- 3.2 ?-d-Glucans.- 3.2.1 Paramylon.- 3.2.2 Leucosin (Chrysolaminarin).- 3.3 Other Polysaccharides.- 4 Reserve Carbohydrates in Fungi.- 4.1 ?-d-Glucans.- 4.1.1 Glycogen Type.- 4.1.2 Other (1?4)- and (1?6)-?-d-Glucans.- 4.1.3 (l?4)-?-d-Glucans.- 4.1.4 (l?3)-?-d-Glucans.- 4.1.5 Nigeran.- 4.2 ?-d-Glucans.- 4.2.1 (1?3)-?-d-Glucans.- 4.3 Other Polysaccharides.- 5 Reserve Carbohydrates of Lichens.- 5.1 ?-d-Glucans.- 5.2 ?-d-Glucans.- References.- 13 Plant Glycoproteins.- 1 Introduction.- 2 Natural Occurrence of Glycoproteins.- 3 Isolation, Fractionation, and Purification.- 3.1 Methods of Extraction: Practical Considerations.- 3.2 Isolation and Purification.- 4 Composition of Glycoproteins.- 5 Structural Studies.- 5.1 Types of Peptide-Carbohydrate Linkages.- 5.2 Structural Studies of the Carbohydrate Groups.- 6 Some of the Better-Defined Glycoproteins and Proteoglycans.- 6.1 Lectins (or Phytoagglutinins).- 6.1.1 Soybean Agglutinin (SBA).- 6.1.2 Lectins from Some Phaseolus vulgaris Species.- 6.1.3 Lima Bean Agglutinin.- 6.1.4 Sainfoin Agglutinin.- 6.1.5 Broad Bean Lectin.- 6.1.6 Potato Lectin.- 6.2 Enzymes.- 6.2.1 Stem Bromelain.- 6.2.2 Ficin.- 6.2.3 Horseradish Peroxidase.- 6.2.4 Invertases.- 6.3 Storage Proteins.- 6.3.1 7S Protein of Soybean.- 6.3.2 Kidney Bean Glycoproteins.- 6.3.3 Vicilin and Legumin.- 6.4 Toxins.- 6.4.1 Ricin D.- 6.5 Intracellular Proteoglycans and Glycoprotein-Polysaccharide Complexes.- 6.5.1 Intracellular Hydroxypyroline-Rich Proteoglycan of Suspension-Cultured Tobacco Cells.- 6.5.2 Glycoproteins and Glycoprotein-Polysaccharide Complexes from the Leaves of Higher Plants.- 6.5.3 Arabinogalactan-Proteins from Higher Plants.- 6.6 Plant Cell Wall Glycoproteins.- 7 Glycoprotein Biosynthesis.- 8 Comparison of Higher Plant Glycoprotein Structure with Those of Microorganisms and Animals.- 8.1 N-Glycosidic Linkages.- 8.2 O-Glycosidic Linkages Through the Hydroxyl Group of Hydroxypyroline or Hydroxylysine.- 8.3 O-Glycosidic Linkage Through the Hydroxyl Group of Serine and Threonine.- 9 Concluding Remarks.- References.- 14 Membrane Glycoproteins.- 1 The Membrane as a Molecular Milieu.- 2 Structure and Mechanisms of Biosynthesis.- 2.1 Structure.- 2.2 Mechanisms of Biosynthesis.- 2.2.1 Use of Model Systems.- 2.2.2 Synthesis of Integral Membrane Proteins.- 2.2.3 Cotranslational Glycosylation.- 2.2.4 Post-Translational Glycosylation.- 2.2.5 Synthesis of Peripheral Membrane Proteins.- 2.2.6 Synthesis of Mitochondrial and Chloroplast Membrane Proteins.- 2.2.7 Summary of Mechanisms of Biosynthesis.- 3 Intracellular Transport.- 3.1 General Principles.- 3.2 Regulation.- 3.2.1 Secretion Signals.- 3.2.2 Retention Signals.- 4 Plant Membrane Glycoproteins.- 4.1 Distribution.- 4.1.1 Cell Surface.- 4.1.2 Intracellular Membranes: GA, ER and Tonoplast.- 4.1.3 Chloroplasts and Mitochondria.- 4.1.4 Microbodies: Glyoxysomes and Peroxisomes.- 4.1.5 Other Membranes.- 4.2 Structure and Mechanisms of Biosynthesis.- 4.3 Intracellular Transport.- 5 Future Perspectives.- References.- 15. Glycolipids and Other Glycosides.- 1 Introduction.- 2 Methods Used in the Isolation and Purification of Glycolipids.- 3 Glycosyl Diglycerides.- 3.1 Mono- and Digalactosyl Diglycerides.- 3.2 Sulfoquinovosyl Diglyceride.- 4 Cerebrosides.- 5 Phytoglycolipids.- 6 Steryl Glucosides.- 7 Lipid-Linked Saccharides.- References.- 16 Steryl Glycosides.- 1 Introduction.- 2 Presence and Structure of Glycosylated Sterols in Plants.- 3 Organ and Cellular Localization of Steryl Glucosides.- 4 Biosynthesis and Degradation of Steryl Glucosides and Acylated Steryl Glucosides.- 5 The Intracellular Location of UDPGlc: Sterol Glucosyl Transferase and Steryl Glucoside Acylase.- 6 Distribution of Steryl Glucosides and Acylated Steryl Glucosides as a Probe of Functions.- 7 Steryl Glucosides and Acylated Steryl Glucosides in Plant Membranes.- 8 Steryl Glucosides as Intermediary Sugar Carriers.- 9 Miscellaneous Activities of Steryl Glucosides in Plants.- References.- III. Physiological Processes.- 17 Transport of Sugar.- 1 Introduction.- 2 Classification of Sugar Transport Across Membranes.- 2.1 Passive Transport (Diffusion).- 2.2 Mediated Diffusion.- 2.3 Active Transport.- 3 Energy Input for Active Sugar Transport.- 3.1 Equilibrium Shift by Substrate Conversion.- 3.2 Primary Active Transport.- 3.3 Secondary Active Transport.- 3.3.1 Proton-Symport in Plants.- 3.3.2 Proton-Translocating ATPases on Plasmalemma and Tonoplast.- 3.3.3 Sugar Uptake Driven by Sugar Efflux.- 4 Kinetic Properties of Sugar Transport Systems.- 4.1 Sugar Transport at Net and Steady-State Conditions.- 4.2 The Sugar Accumulation Ratio.- 4.3 Effect of Metabolic Inhibitors on Transport Kinetics.- 4.4 Influence of Proton-Gradient and Membrane Potential on Kinetics.- 5 Transport Proteins.- 6 Regulation of Sugar Transport.- 6.1 Induction and Repression.- 6.2 Transport Regulation by Direct Effectors.- 7 Relevance of Sugar Transport Systems for Plant Cells.- 8 Concluding Remarks.- References.- 18 Secretion of Nectar.- 1 Introduction.- 2 Route of Transport.- 2.1 Apoplastic Transport.- 2.2 Symplastic Transport.- 3 Sites of Membrane Transport.- 3.1 At the Phloem.- 3.2 To the Exterior.- 3.2.1 Modifications Increasing the Secreting Surface.- 3.2.2 Protoplast Specialization.- 4 Metabolism.- 4.1 Sugar Interconversion.- 4.2 Energy Metabolism.- 4.3 Phosphatases.- 4.4 Sugar Transport.- References.- 19 Storage of Sugars in Higher Plants.- 1 Introduction.- 2 Functional Anatomy of Storage Tissues.- 3 Translocation of Sucrose to the Storage Organs.- 4 Storage of Sugars in Fruits.- 5 Storage of Sucrose in Sugarcane.- 6 Storage of Sucrose in Roots and Beets.- 7 Transfer of Sucrose into the Vacuole.- 8 Remobilization of Sugars from the Storage Compartment.- 9 Concluding Remarks.- References.- 20 Storage of Starch.- 1 Introduction.- 2 Occurrence of Starch.- 2.1 Global Data.- 2.2 Measurement of Starch.- 2.2.1 Occurrence - Dry Fruits.- 2.2.2 Occurrence - Fleshy Organs.- 3 Patterns of Accumulation.- 3.1 Temporal.- 3.2 Ontogenetic Patterns.- 3.2.1 Inception.- 3.2.2 Acceleration.- 3.2.3 The Grand Phase of Accumulation.- 3.2.4 Termination.- 4 Distribution of Starch.- 4.1 Within Storage Organs.- 4.1.1 Vegetative Organs.- 4.1.2 Seeds.- 4.2 Between Storage Organs.- 5 Plastids.- 5.1 Origin and Development.- 5.2 Developmental Homologies.- 5.3 Biochemical Attributes of Plastids.- 5.3.1 Nucleic Acids.- 5.3.2 Enzymes.- 5.4 Stability of Amyloplast Membranes.- 6 Granules.- 6.1 Morphology.- 6.2 Initiation of Granules.- 6.3 Growth of Granules.- 6.3.1 Growth and Lamellae.- 6.3.2 Mechanism of Growth.- 6.3.3 Growth and Changes in Composition.- 6.3.4 Granule Size and Composition.- 7 Metabolism of Starch.- 7.1 Substrates and Precursors.- 7.2 Pathways of Synthesis.- 7.3 Degradation of Starch.- 7.4 The Turnover of Starch.- 7.5 Distribution of 14C.- 8 Regulatory Mechanisms.- 8.1 Intracellular Controls.- 8.2 Supply of Substrate.- 8.2.1 The Seed.- 8.2.2 Fruits, Roots, and Tubers.- 8.2.3 Control by Transport of Substrate.- 8.3 Growth of Storage Organs.- 9 Environmental Influence.- 9.1 Irradiance.- 9.2 Temperature.- 9.3 Water Deficit.- 9.4 Mineral Nutrition.- 10 Summary and Conclusions.- References.- 21 Control by External and Internal Factors Over the Mobilization of Reserve Carbohydrates in Higher Plants.- 1 Introduction.- 2 Seeds.- 2.1 Starch in Cereals.- 2.1.1 Gibberellins and ?-Amylase Synthesis by the Barley Aleurone Layer.- 2.1.2 Gibberellins and the Synthesis of Other Carbohydrases in Barley Grains.- 2.1.3 Gibberellin-Induced Enzymes in Other Cereal Grains.- 2.2 Starch in Legumes.- 2.2.1 Control by the Axis.- 2.3 Mannans in Seed Endosperms.- 2.3.1 Legumes.- 2.3.2 Lettuce.- 2.3.3 Umbellifers and Palms.- 2.4 Other Cell Wall Polysaccharides.- 2.5 Raffinose-Oligosaccharides.- 3 Tubers, Roots, and Bulbs.- 3.1 Fructans in Jerusalem Artichoke Tubers, and Other Roots and Bulbs.- 3.2 Starch in Potato Tubers.- 4 Starch in Leaves.- 5 Fleshy Fruits.- 5.1 Starch.- 5.2 Cell Wall Polysaccharides.- 6 Thermogenesis in Aroids.- 7 Changes in Stems, Roots, and Leaves Associated with Environmental Stresses.- 8 Starch in Organogenesis.- References.- Author Index.- Species Index.