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1Author    GeorgH. Schmid, Pierre ThibaultRequires cookie*
 Title    Studies on the S-State Distribution in Euglena gracilis  
 Abstract    When Euglena gracilis is dark adapted for 10 min or more, oxygen evolution as the conse­ quence of short (5 usee) saturating light flashes does not show the picture of a damped oscillation with a periodicity o f 4, as known from the literature. The overall picture of this flash pattern is given by the fact that 0 2-evolution in the First two flashes is practically zero and rises from there onward in a continuous manner to the steady state with barely any visible oscillation at all. However, a second flash sequence fired one to two minutes after this first sequence induces an oxygen evolution pattern which is barely distinguishable from the well known usual Chlorella vulgaris pattern. The phenomenon is not influenced by changes in the oxygen tension nor do additions of chemicals like CCCP, sodium azide, or reducing agents like hydroxylamine or hydrogen peroxide substantially alter the described behavior. Deactivation experiments give the overall impression that the deactivation of the S-states is slower than with Chlorella. Hydroxylamine strongly accelerates the deactivation. The analysis of the S-state distribution in a four and five state Kok-model suggests that dark adapted Euglena is in a more reduced condition than dark adapted Chlorella. It looks as if dark adapted Euglena were in a condition which would correspond to 60 percent S_|, 30 percent S0 and 10 percent S). The experimental flash sequence of such dark adapted cells fits best a synthetic sequence when the misses are in the region of 2 0 -2 5 percent, with double hitting playing practically no role at all (the first two flashes are zero!). The impression that dark adapted Euglena starts its oxygen evolution from a more reduced state is strengthened by the analysis of room temperature fluorescence induction (Kautsky effect). It can be shown that the fluorescence induction curve o f Euglena corresponds to that of Chlorella cells provided the latter have been briefly treated with a strong reductant such as sodium dithionite. 
  Reference    Z. Naturforsch. 38c, 60—6 (1983); received September 1982 
  Published    1983 
  Keywords    Flash Yield, Oxygen, Euglena, Fluorescence Induction 
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 TEI-XML for    default:Reihe_C/38/ZNC-1983-38c-0060.pdf 
 Identifier    ZNC-1983-38c-0060 
 Volume    38 
2Author    Ahlert Schmidt, Elisabeth KrämerRequires cookie*
 Title    A Membrane Bound Cysteine Oxydase from the Cyanobacterium Synechococcus 6301  
 Abstract    Membrane fractions o f the cyanobacterium Synechococcus 6301 obtained by french press treatment following sonication catalyzed an oxygen-dependent oxydation o f cysteine to cystine. For 1 0 2 consumed four cysteine were oxydized. O xygen uptake was com pletely inhibited by 1 mM KCN. Only D-and L-cysteine were active and partial activity was observed with DL-homocysteine and cysteamine. N o activity was found with glutathione, mercaptoethanol, thioglycerol, dithioerythritol, or N-acetyl-L-cysteine. Cysteines with a blocked acid group such as O-methyl-L-cysteine and O-ethyl-L-cysteine were oxydized rapidly by Synechococcus m em brane fractions. Rates o f about 200 (imol o f cysteine oxydized per mg chlorophyll and hour were measured. This cysteine respiration is discussed in relation to dark inactivation o f enzymes. 
  Reference    Z. Naturforsch. 38c, 446—450 (1983); received February 22 1983 
  Published    1983 
  Keywords    Cysteine Oxydation, Oxygen, Thiol Compounds, Synechococcus, Cyanobacteria 
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 TEI-XML for    default:Reihe_C/38/ZNC-1983-38c-0446.pdf 
 Identifier    ZNC-1983-38c-0446 
 Volume    38 
3Author    Fabrice Franck, GeorgH. SchmidRequires cookie*
 Title    Flash Pattern of Oxygen Evolution in Greening Etioplasts of Oat  
 Abstract    Etioplasts isolated from oat leaves that have received two 5 m in illum ination periods, spaced apart by a 90 min dark interval, are able to evolve oxygen. If this oxygen evolution is measured as consequence o f short saturating light flashes a pattern is obtained w hich in agreem ent with the Kok-Joliot model shows a dam ped oscillation w ith a periodicity o f four. As usual for most other systems the maximum flash yield is observed under the third flash. In continuous light such slightly greened etioplasts show a small oxygen gush. From our studies it appears that the second 5 min illumination period is obligatory for oxygen evolution. O m ission o f this period leads to a condition in which under flashes strictly no oxygen is evolved. In continuous light under these conditions no oxygen gush but rather an uptake is observed after onset o f illum ination. It appears that in greening etioplasts the flash pattern shows som e peculiarities when compared to the normal green conditions. Thus, a flash sequence o f a greening etioplast always shows a substantial positive amperometric signal under the first flash. The h alf tim e o f the state which would belong to this signal is 3 to 4 min in a greening etioplast, isolated from leaves that have received 2 h light. In the course o f greening this h alf tim e decreases continuously and reaches a normal and constant value o f approx. 1 0 s in chloroplasts from green oat or etiochloroplasts that are prepared from leaves that have received 15 h o f light. The result is discussed in terms o f metastable S3 which seems to be a property o f the developing oxygen evolving system in greening oat leaves. In the greening system as we use it is shown for the first tim e that the photoenzym e protochlorophyllide chlorophyllide reductase is D C M U sensitive. 
  Reference    Z. Naturforsch. 39c, 1091 (1984); received August 17 1984 
  Published    1984 
  Keywords    Flash Yield, Oxygen, S-States, Etioplasts 
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 TEI-XML for    default:Reihe_C/39/ZNC-1984-39c-1091.pdf 
 Identifier    ZNC-1984-39c-1091 
 Volume    39 
4Author    MarcelA K Jansen3, Shmuel Malkinb, Marvin EdelmanaRequires cookie*
 Title    Differential Sensitivity of 32 kDa-D 1 Protein Degradation and Photosynthetic Electron Flow to Photosystem II Herbicides  
 Abstract    Degradation of the 32 kDa-D 1 protein, a photosystem II reaction centre component, was studied as a function of linear electron flow in visible light in the presence of various photosys­ tem II herbicides. Under these conditions, herbicide specific effects on protein degradation were clearly evident. 32 kDa-D 1 protein degradation and electron flow between Q a and Q b proved to be only partially correlated. We conclude that inhibition of protein degradation by PS II herbicides in visible light is not simply correlated to displacement of Q b. 
  Reference    Z. Naturforsch. 45c, 408—411 (1990); received December 12 1989 
  Published    1990 
  Keywords    Diuron, Bromoxynil, Dinoseb, Oxygen, Evolution, Chlorophyll, Fluorescence 
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 TEI-XML for    default:Reihe_C/45/ZNC-1990-45c-0408.pdf 
 Identifier    ZNC-1990-45c-0408 
 Volume    45 
5Author    KennethE. Pallett, AlanD. DodgeRequires cookie*
 Title    The Role of Light and Oxygen in the Action of the Photosynthetic Inhibitor Herbicide Monuron  
 Abstract    Monuron treatment of detached flax cotyledons caused a rapid inhibition of C 02 fixation in darkness and light. Chlorophyll breakdown was promoted by increased light intensity. Ethane generation, an indicator of membrane damage, increased as the chlorophyll level decreased. The carotene pigments were destroyed more rapidly than the xanthophylls and chlorophylls. Treatment of cotyledons with monuron in the absence of oxygen almost prevented carotenoid and chlorophyll loss. The addition of the singlet oxygen quencher DABCO delayed chlorophyll breakdown. The results are discussed in relation to a role for singlet oxygen in the herbicidal action of monuron. 
  Reference    Z. Naturforsch. 34c, 1058—1061 (1979); received May 29 1979 
  Published    1979 
  Keywords    Herbicidal Action of Monuron, Light, Oxygen, Singlet Oxygen, Plant Pigments 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-1058.pdf 
 Identifier    ZNC-1979-34c-1058 
 Volume    34 
6Author    M. Molwitz3, S. S. Silvab, J. D. Ribeiro, I.C R Oberto, M.G A Felipe, A.M R Pratab, I. M. MancilhabRequires cookie*
 Title    Aspects of the Cell Growth of Candida guilliermondii in Sugar Cane Bagasse Hydrolysate  
 Abstract    In this work the behavior of the growth of Candida guillierm ondii FTI 20037 in sugar cane bagasse hemicellulosic hydrolysate on various oxygen transfer rates was investigated. The yeast was able to grow and produced xylitol at different performence levels. At 1.0 vvm (volume of air per volum e of medium per minute) the highest growth with 24.4 g/1 was observed, but no xylitol was produced. At aeration rate of 0.5 vvm the growth was lower, but therefore slight amounts of xylitol (xylitol yield factor -y p/s = 0.15 g/g) were observed. The lowest cell concentration (10.7 g/1) and the highest xylitol yield (Y p/s = 0.46 g/g) was observed when aeration was changed from 0.5 vvm to 0.05 vvm after 14 h. 
  Reference    Z. Naturforsch. 51c, 404 (1996); received October 3 0 /December 20. 1995 
  Published    1996 
  Keywords    Candida guillierm ondii, Oxygen, Sugar Cane Bagasse, Xylose, Xylitol Fermentation 
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 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0404.pdf 
 Identifier    ZNC-1996-51c-0404 
 Volume    51