Inorganic Nitrogen Metabolism

At a meeting of the Federation of European Societies of Plant Physiology in 1984 in Strasbourg the idea of having a special meeting on inorganic nitrogen metabolism on a more or less European level was born. Originally it was planned to limit its content to the inorganic nitrogen metabolism of eukary­ otic algae and cyanobacteria, but later the Organizing Committee decided to widen the scope of the meeting. Thus, what resulted was a Symposium, or rather an Advanced Course, on Inorganic Nitrogen Metabolism, including, in addition to algal biochemistry and physiology, some coverage of nitrogen­ fIxing bacteria, a large area that could only be touched on during the course and in which newer ideas from molecular biology are much involved, and, to some extent, of the biochemistry and physiology of fungi and higher plants. Not all of the speakers originally invited could come and contribute, but the Table of Contents shows that the meeting was able to survey reasonably adequately, the present state of research on nitrogen assimilation by plants. The speakers were asked to present recent results from their laboratories in the context of a survey of background knowledge, thus the articles in this volume sometimes partially overlap, but never so much that there is not an interesting and complementary approach to the same problem from several sides. Therefore, the editors decided not to interfere with the texts of the authors and to risk some repetition; e. g.

1 Basic Aspects.- Energetics and C-Assimilation.- 1 Photosynthetic Assimilation of the Primordial Bioelements.- 2 Responses of Microalgae to Changes in CO2 Concentration.- 2 General Survey on Uptake and Metabolism of Inorganic Nitrogen.- Eukaryotic Algae and Higher Plants.- 3 Nitrogen Assimilation by Eukaryotic Algae.- 4 Nitrate and Ammonium Uptake in Green Algae and Higher Plants: Mechanism and Relationship with Nitrate Metabolism.- 5 Comparative Aspects of Inorganic Nitrogen Assimilation in Higher Plants.- Prokaryotes.- 6 Interactions Between Photosynthetic Nitrate Assimilation and CO2 Fixation in Cyanobacteria.- 7 Nitrogen Metabolism in Heterotrophic Bacteria. A Comparative Study of the Short-Term Ammonium Inhibition of Dinitrogen Fixation and of Nitrate Assimilation in Azotobacter chroococcum.- 8 Novel Terminal Oxidoreductases of Anaerobic Respiration (Denitrification) from Pseudomonas.- 3 Enzymes of Inorganic Nitrogen Metabolism.- Nitrate Reductase.- 9 Structure-Function Relationships of Assimilatory Nitrate Reductase.- 10 Photoregulation of Nitrate Assimilation in Eukaryotic Organisms.- 11 Regulation and Signal Transduction in Nitrate Reductase of Neurospora crassa.- 12 The Regulation of Nitrate Reductase in Yeasts.- 13 Immunological Approaches to Inorganic Nitrogen Metabolism.- 14 Regulation of Nitrate Reductase in Maize: An Immunochemical Approach.- 15 Quantitation of Nitrate Reductase Protein by Enzyme-Linked Immunosorbent Assay (ELISA) with Monoclonal Antibodies.- 16 Genetic Control of Nitrate Reductase in the Green Alga Chlamydomonas reinhardtii.- 17 Nitrite Reductase.- 18 Structural Studies on the Siroheme-[4Fe-4S] Cluster Active Centers of Spinach Ferredoxin-Nitrite Reductase and Escherichia coli Sulfite Reductase.- 19 Nitrite Reduction in Leaf and Root.- Enzymes of Ammonium Metabolism.- 20 Regulation of Ammonium Incorporation.- 21 Enzymology of the Assimilation of Ammonium by the Green Alga Chlamydomonas reinhardtii.- 22 The Roles of Glutamine Synthetase and Glutamate Synthase in Nitrogen Metabolism of Higher Plants.- 23 Glutamate Synthase Cycle in the Leaves of Tomato (Lycopersicon esculentum).- 24 Regulation by Ammonia of Glutamine Synthetase from Unicellular Cyanobacteria.- 25 Enzymology of Ammonia Assimilation in Purple Nonsulfur Bacteria.- Nitrogenase and Related Hydrogenase Activities.- 26 Regulation of Nitrogen Fixation in Photosynthetic Bacteria.- 27 Genetic Studies on the Hydrogen-Uptake System of Rhizobium.- 28 Nitrogen Fixation in Rhizobium. Some General Features.- 29 ATP and Nitrogen Fixation.- 30 The Reversible Inhibition in Nitrogen Fixation by Oxygen.- 31 Redox Properties of the Hydrogenase of Chemolithotrophically Grown Rhizobium japonicum.- 32 The Bacterial Genus Azospirillum and Its Potential Applications.- 33 The Photoreduction of N2 to Ammonium and Amino Acids by Cyanobacteria.- Other Enzymes and Coenzymes.- 34 Presence of an Amino Acid Oxidase in O2 Evolving Photosystem II Preparations from the Cyanobacterium Anacystis nidulans.- 35 Properties of the Protein-Bound Phosphorus Groups in Flavodoxin from Azotobacter vinelandii.- Metalloproteins in Nitrogen Metabolism and Related Processes.- 36 Mechanism and Regulation for Multielectron Steps in Metalloproteins.- 37 The Significance of Iron-Nitrosyl Complexes in Biology and in the Reaction of Assimilatory Nitrite Reductase.- 38 Metalloproteins Involved in the Inorganic Nitrogen Metabolism of Chlamydomonas reinhardtii and Other Green Algae.- 39 The nifH Gene Product is Essential for the Production of the Active FeMoco of Klebsiella pneumoniae Nitrogenase.- 40 Eukaryotic Iron-Containing Superoxide Dismutase from Ginkgo biloba.- 4 Regulation of Nitrogen Utilization and Special Topics.- Regulation in Algae and Cyanobacteria.- 41 Regulation of Nitrate Utilization in Green Algae.- 42 Impact of UV-B Radiation on the Assimilation of Inorganic 15 N-Nitrogenous Compounds by Marine Diatoms.- 43 Nitrogen Metabolism in Thermophilic Algae.- 44 Ammonium Uptake and Assimilation in the Alkalophytic Cyanobacterium Spirulina platensis.- 45 Sustained Photoproduction of Ammonia from Nitrate or Nitrite by Free and Immobilized Cells of Phormidium laminosum.- Regulation in Higher Plants.- 46 Regulation of Nitrate Utilization in Higher Plants.- 47 Proton Disposal During Plant Growth with NH4+, NH3, (NH2)2 CO, or N2 as N-Source: Must Excess H+ Always be Excreted?.- 48 K+ Modulation of Nitrogen Uptake and Assimilation in Plants.- 49 Differential Distribution of Carbon in Response to Nitrate, Ammonium, and Nitrate + Ammonium Nutrition in Wheat.- 50 Effect of Form and Concentration of Nitrogen on the CO2 Gas Exchange in the Light for Selected C4 Photosynthetic Grasses.- 51 Effect of Ammonium and Nitrate Nutrition on the Growth of Carob (Ceratonia siliqua L.) Plants.- 52 Appearance of Nitrite Reductase (NIR) and Nitrate Reductase (NR) in Cotyledons of the Mustard (Sinapis alba L.) Seedling as Affected by Nitrate, Ammonium, Phytochrome, and Photooxidative Damage of Plastids.- References.