Go toArchive
Browse byFacets
Bookbag ( 0 )
'Nitrogenase' in keywords
Results  6 Items
Sorted by   
Publication Year
1993 (1)
1980 (2)
1979 (1)
1978 (2)
1Author    R. Stripf, D. WernerRequires cookie*
 Title    Differentiation of Rhizobium japonicum. II. Enzymatic Activities in Bacteroids and Plant Cytoplasm during the Development of Nodules of Glycine max  
 Abstract    Phytotron grown plants of Glycine max var. Caloria infected with Rhizobium japonicum 61-A-101 under controlled conditions as 14 d old seedlings develop a sharp maximum of nitrogenase activity 
  Reference    Z. Naturforsch. 33c, 373—381 (1978); received March 16 1978 
  Published    1978 
  Keywords    Rhizobium japonicum, Glycine max, Bacteroids, Nodules, Nitrogenase 
  Similar Items    Find
 TEI-XML for    default:Reihe_C/33/ZNC-1978-33c-0373.pdf 
 Identifier    ZNC-1978-33c-0373 
 Volume    33 
2Author    Renate Horcher, John Wilcockson, D. Ietrich, W. ErnerRequires cookie*
 Title    Screening for Mutants of Rhizobium japonicum with Defects in Nitrogen Fixing Ability  
 Abstract    Mutants o f Rhizobium japonicum with reduced ex planta nitrogenase activity could be isolated with high frequency by direct screening of ultra-violet mutagenized bacteria growing as spots on the surface o f an appropriate agar medium permitting derepression of nitrogenase synthesis. Small glass chambers fitted with a serum cap were pushed into the agar around each spot of growth, forming a small enclosed gas space which was made to 10% acetylene, permitting assessment o f nitrogenase activity by the acetylene reduction test. Four mutants were isolated from a total of 305 screened spots. Two mutants had almost no ex planta activity, one o f which had no symbiotic activity despite normal nodulation (ineffective), the other had only somewhat reduced activity symbiotically. Two other mutants with less than half wild-type activity ex planta were normal in symbiosis. 
  Reference    Z. Naturforsch. 35c, 729—732 (1980); received May 30 1980 
  Published    1980 
  Keywords    Rhizobium japonicum, Nitrogenase, Nif-Mutants, Ineffective Nodules 
  Similar Items    Find
 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0729.pdf 
 Identifier    ZNC-1980-35c-0729 
 Volume    35 
3Author    G. Erhard, N. Schrauzer, PaulA. Doemeny, JohnG. PalmerRequires cookie*
 Title    The Chemical Evolution o f a Nitrogenase Model, XXII. Reduction of Acetylene with Catalysts Derived from Molybdate, Homocitric Acid and N-M ethylimidazole and a Proposal Concerning the Active Site of Functional Azotobacter Nitrogenases  
 Abstract    Based on model experiments it is suggested that the reduction o f substrates by nitrogenase occurs at a m ononuclear site containing molybdenum, homocitrate and the imidazole com ponent of his-442 o f the apoenzyme, generated from the FeMo-co by a reversible dissociation of the Fe7S8 unit from the M oFe7S8 cluster in a redox-linked process. 
  Reference    Z. Naturforsch. 48b, 1295—1298 (1993); received May 14 1993 
  Published    1993 
  Keywords    Nitrogenase, Acetylene Reduction, M olybdenum-Catalyzed, Homocitric Acid, Histidine, Imidazole 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/48/ZNB-1993-48b-1295_n.pdf 
 Identifier    ZNB-1993-48b-1295_n 
 Volume    48 
4Author    R. Stripf, D. W. Em ErRequires cookie*
 Title    Development of Discontinuous Size Classes of Nodules of Glycine max  
 Abstract    In order to characterize developmental stages o f nodules of Glycine max nitrogenase activity in the variety Caloria, infected with Rhizobium japonicum 61-A -101, was studied in atmospheres with 19 and 40% 0 2. By the enhancement effect at 40% 0 2 four stages o f nodule development could be separated. Nitrogenase activity depends also among other things on nodule size. 3 -4 maxima in nodule number and nodule weight were found by fractionating nodules in 12 different size classes. Discontinuous size distribution was found with medium aged and old effective nodules. Nodule number (20 to 30) o f effective nodules per plant remains constant. Ineffective nodules remain far smaller than the effective ones, the number increases to more than 140 per plant and only one discontinuous size classe was observed. Bacteroids and plant cytoplasm from nodules of some size classes are characterized by their leghaemoglobin content and specific activity of enzymes o f nitrogen metabolism such as aspartate aminotransferase (E.C., glutamate dehydrogenase (E.C. and alanine de­ hydrogenase (E.C. The data in the various size classes are similar both in the bacteroids and the plant cytoplasm, however, leghaemoglobin content and specific activity o f the bacterial enzyme alanine dehydrogenase are positively correlated with the increasing nodule size. 
  Reference    Z. Naturforsch. 35c, 776—7 (1980); received May 30 1980 
  Published    1980 
  Keywords    Rhizobium japonicum, Glycine max, Nodules Size Classes, Nitrogenase, Leghaemoglobin 
  Similar Items    Find
 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0776.pdf 
 Identifier    ZNC-1980-35c-0776 
 Volume    35 
5Author    Hartmut Spiller, Anneliese Ernst, Wolfgang Kerfin, Peter BögerRequires cookie*
 Title    Increase and Stabilization of Photoproduction of Hydrogen in Nostoc muscorum by Photosynthetic Electron Transport Inhibitors  
 Abstract    Nittrogen-fixing cells of N o s to c m u s co ru m grown under nitrogen or in the presence of nitrate exhibit substantial light-induced hydrogen production for over 15 hours in the presence of electron transport inhibitors. Rates attain levels of 12 //mol H 2 evolved/ml packed cell volume and hour. The ATP-dependent nitrogenase, not a hydrogenase, is responsible for hydrogen production. This is indicated by poor sensitivity to CO and inhibition of the reaction by uncouplers, acetylene, and N 2 . A n active uptake hydrogenase minimizes light-induced H 2 production. Although nitrogenase activity is somewhat decreased by several photosynthetic electron transport inhibitors, hydrogen production is markedly increased. This is due to lowering the partial pressure of oxygen in the cell, preventing oxidative hydrogen consumption. 
  Reference    Z. Naturforsch. 33c, 541 (1978); received M ay 24 1978 
  Published    1978 
  Keywords    Cyanobacteria, W ater Photolysis, Nitrogenase, Uptake Hydrogenase, Photoproduction of Hydrogen, Photosynthetic Electron Transport Inhibitors 
  Similar Items    Find
 TEI-XML for    default:Reihe_C/33/ZNC-1978-33c-0541.pdf 
 Identifier    ZNC-1978-33c-0541 
 Volume    33 
6Author    Anneliese Ernst, Wolfgang Kerfin, Hartmut Spiller, Peter BögerRequires cookie*
 Title    External Factors Influencing Light-Induced Hydrogen Evolution by the Blue-Green Alga, Nostoc muscorum  
 Abstract    This study was conducted to determine some physiological conditions which influence light-in­ duced hydrogen evolution by intact cells of the blue-green alga Nostoc muscorum. This activity was found to be dependent on the age of the culture, cultivation temperature, ageing of the cells, and on gassing the cultures with nitrogen or air. Nitrogenase is particularly ac­ tive after cultivation at 22 °C but not at 32 °C although growth is about the same. The molar ratio of acetylene reduction to hydrogen evolution -both gas exchanges obviously catalyzed by nitrogen­ ase -is also dependent on age and temperature of the culture. A hydrogen-consuming ("up­ take") hydrogenase activity is present and affected by prolonged microaerobic, but not by aerobic growth conditions, and stimulated by light. External factors during growth apparently influence differently the activities of nitrogenase and uptake hydrogenase. Consequently -besides the electron donor supply -net light-induced hydro­ gen evolution by intact cells is dependent on these two variable activities. 
  Reference    Z. Naturforsch. 34c, 820 (1979); received May 8/June 11 1979 
  Published    1979 
  Keywords    Photoproduction of Hydrogen, Cyanobacteria, Heterocysts, Water Photolysis, Nitrogenase, Uptake Hydrogenase 
  Similar Items    Find
 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0820.pdf 
 Identifier    ZNC-1979-34c-0820 
 Volume    34