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'Rhodopseudomonas capsulata' in keywords
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1984 (1)
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1980 (1)
1Author    Kassem AlefRequires cookie*
 Title    in Rhodopseudomonas capsulata AD 2  
 Abstract    Nitrate assimilation by Rhodopseudomonas capsulata A D 2 was com pletely inhibited by ammonium only in young well illuminated cultures. At higher densities (A660 about 0.5) the addition o f ammonium had no inhibitory effect, but the nitrate was only reduced to the level o f nitrite, which appeared in the medium. Under both conditions the cellular level o f nitrate reductase activity remained unaffected. In marked contrast to other R. capsulata strains both ammonium sensitive and insensitive cells could reduce nitrate in the light and in the darkness. In the light up to 90% of the reduced nitrate was assim ilated, but in the dark the reduced nitrate was stoichiometrically excreted as nitrite. This behaviour was only shown by R. capsulata A D 2 and BK5, while in other strains the nitrate assim ilation was always com pletely inhibited by ammonium. The role o f photosynthesis and respiration by the regulation o f nitrate reduction is discussed. 
  Reference    Z. Naturforsch. 39c, 85—8 (1984); received Novem ber 10 1983 
  Published    1984 
  Keywords    Nitrate Reduction, Regulation, Rhodopseudomonas capsulata 
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 TEI-XML for    default:Reihe_C/39/ZNC-1984-39c-0085.pdf 
 Identifier    ZNC-1984-39c-0085 
 Volume    39 
2Author    G.Erhard Talsky, ComelisP. Rygersberg, Rien Van Grondelle, Reiner Feick, G.Erhart DrewsRequires cookie*
 Title    Derivative Absorption Spectroscopy of the Pigment-Protein Complexes from Rhodopseudomonas capsulata  
 Abstract    The near infrared absorption spectra and their fourth derivative were measured in membrane preparations or in the isolated light harvesting pigment-protein complex B 800-850 from Rhodopseudomonas capsulata in order to know how the underlying molecular absorption spectra contribute to the observed absorption curve. In contrast to the observations o f Cogdell and Crofts [Biochim. Biophys. Acta 502, 409 (1978)] no splitting o f the 855 nm absorption bands was observed at 300 K, 100 K, and 4 K. However, a small but significant splitting o f the 870 nm band in all derivates (2nd, 4th, 6th) was observed at 300 K and 4 K. The lack o f splitting of the 855 nm absorption band will be discussed in the light o f the molecular organization of the B 855 moiety o f this light harvesting bacteriochlorophyll-protein complex. 
  Reference    Z. Naturforsch. 35c, 722—725 (1980); received June 41980 
  Published    1980 
  Keywords    Derivative Absorption Spectroscopy, Bacteriochlorophyll-Protein Complex, Rhodopseudomonas capsulata 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0722.pdf 
 Identifier    ZNC-1980-35c-0722 
 Volume    35 
3Author    Toshihisa Ohshima, Gerhart DrewsRequires cookie*
 Title    Isolation and Partial Characterization of the Membrane-Bound NADH Dehydrogenase from the Phototrophic Bacterium Rhodopseudomonas capsulata  
 Abstract    Chem otrophically grown cells of Rhodopseudomonas capsulata contain at least three different pyridine nucleotide dehydrogenases, i) a soluble, found in the supernatant (144000 x g) o f cell free extracts, N AD H-dependent, ii) a mem brane-bound, N AD H -dependent, and iii) a soluble, found in the supernatant N AD PH dependent. i The m em brane-bound N A D H dehydrogenase (E.C. 1.6.99.3) has been solubilized by sodium deoxycholate treatm ent of m em branes and purified 75 fold by column chrom atography on Sephadex G-150 and DEAE cellulose in the presence of sodium cholate. The native enzyme has an apparent molecular mass (M r) o f 97 000, containing polypeptides of Mr of about 15 000. The pH optim um was at 7.5. The enzyme was specific for NADH. The Michaelis constant for NADH and DCIP were 4.0 and 63 hm, respectively. The enzyme was inactivated by FM N, riboflavin and NADH. In contrast, the soluble N ADH-dehydrogenase (i) was activated by FMN. 
  Reference    Z. Naturforsch. 36c, 400 (1981); received February 23/M arch 16 1981 
  Published    1981 
  Keywords    NADH Dehydrogenase, Purification, Localization, Inhibitors, Rhodopseudomonas capsulata 
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 TEI-XML for    default:Reihe_C/36/ZNC-1981-36c-0400.pdf 
 Identifier    ZNC-1981-36c-0400 
 Volume    36 
4Author    Werner Aretz, Herwig Kaspari, Jobst-Heinrich KlemmeRequires cookie*
 Title    Molekulare und kinetische Charakterisierung der Xanthin-Dehydrogenase aus dem phototrophen Bakterium Rhodopseudomonas capsulata Molecular and Kinetic Characterization of Xanthine Dehydrogenase from the Phototrophic Bacterium Rhodopseudomonas capsulata  
 Abstract    The structural and kinetic properties of xanthine dehydrogenase (EC 1.2.1.37) from the facultative phototrophic bacterium Rhodopseudomonas capsulata were studied. The enzyme was fully induced when hypoxanthine or xanthine, but less effectively when uric acid served as nitrogen source during growth. The enzyme was purified about 2300-fold from cells grown photosynthetically with hypoxanthine as N-source by using ammoniumsulfate precipitation, gel filtration, ion-exchange and affinity chromatography. The molecular weight as determined by gel filtration throug Sephacryl S-300 was 345000. Subunit analysis by sodium dodecyl sulfate gel electrophoresis suggested a composition o f four identical subunits with a molecular weight o f 84000. The enzyme contained 2 flavin, 2 molybdenum and 8 iron-sulfur groups per mol. The turnover number with hypoxanthine and NAD as substrates was 12000 min-1. Hypoxanthine, 1-methylhypoxanthine, 8-azahypoxanthine, xanthine, 1-methylxanthine, 2-hydroxypurine, 6,8-di-hydroxypurine, 5-azacytosine and 5-azauracil served as electron donors. The most effective electron acceptor was NAD. The kinetic constants (K m) were (in (i m): 52.5 (hypoxanthine); 32.5 (xanthine) and 61.2 (NAD). Various purine compounds inhibited the enzyme competitively in respect to hypoxanthine as substrate. Although reduction of uric acid to xanthine was not detected by using purified enzyme preparations, in v;>o-experiments with 14C-labelled uric acid indicated that the enzyme xanthine dehydrogenase participates in uric acid degradation in Rps. capsulata. According to their electrophoretic mobilities, the xanthine dehydrogenases isolated from hypoxanthine-and uric acid-grown cells were identical. 
  Reference    Z. Naturforsch. 36c, 933—941 (1981); received July 10 1981 
  Published    1981 
  Keywords    Xanthine Dehydrogenase, Phototrophic Bacteria, Rhodopseudomonas capsulata 
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 TEI-XML for    default:Reihe_C/36/ZNC-1981-36c-0933.pdf 
 Identifier    ZNC-1981-36c-0933 
 Volume    36 
5Author    Jürgen Beck, Gerhart DrewsRequires cookie*
 Title    Tetrapyrrol Derivatives Shown by Fluorescence Emission and Excitation Spectroscopy in Cells of Rhodopseudomonas capsulata Adapting to Phototrophic Conditions  
 Abstract    Aerobically in the dark grown cells were incubated semiaerobically (30 min) and afterwards 180 min anaerobically in the light During phototrophic induction the bacteriochlorophyll concentra­ tion increased from 0.26 to 2 . 1 0 nmol/mg cell protein. In samples taken at different times after lowering o f oxygen partial pressure the following tetrapyrrol derivatives were identified by fluorescence emission and excitation spectroscopy at 1.7 K: Mg-protoporphyrin EX-monomethylester, Mg-2,4-divinylphaeoporphyrin a5-monomethylester, 2-de-vinyl-2 -hydroxyethyl-chlorophyllide, 2 -devinyl-2 -hydroxyethyl-pheophorbide, chlorophyllide a, pheophorbide, bacteriopheophorbide, bacteriopheophytin, bacteriochlorophyllide and bacte­ riochlorophyll a in different pigment complexes. The highest relative concentrations o f bacte­ riochlorophyll precursors normalized to the total amount o f bacteriochlorophyll a were found in cells during the first hour o f adaptation at 0.5 ^g Bchl/mg cell protein or less. 
  Reference    Z. Naturforsch. 37c, 199 (1982); received December 29 1981 
  Published    1982 
  Keywords    Bacteriochlorophyll Complexes, Precursors, Tetrapyrrols, Rhodopseudomonas capsulata, Photosynthetic Apparatus 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-0199.pdf 
 Identifier    ZNC-1982-37c-0199 
 Volume    37 
6Author    Hendrik Hüdig, Gerhart DrewsRequires cookie*
 Title    Isolation of a b-Type Cytochrome Oxidase from Membranes of the Phototrophic Bacterium Rhodopseudomonas capsulata  
 Abstract    A cytochrome oxidase (EC 1.9.3.1) was solubilized from the membrane fraction o f aerobically grown cells of Rhodopseudomonas capsulata by treatment with Triton X-100. The enzyme was purified 160 fold by chromatography on DEAE-Sepharose CL -6B and affinity chromatography on cytochrome c-thiol activated Sepharose 4B. The purified enzyme has a pH-optimum at 8.5 and a temperature optimum at 35 °C. The ap­ parent K m for reduced horse cytochrome c is 24 |iM (at pH 8 and 30 °C). The purified cytochrome oxidase was 50% inhibited by 1.5 |iM KCN and 10 (iM N aN ,. The purified enzyme contained one polypeptide of mT 65,000 and 6-type cytochrome. 
  Reference    Z. Naturforsch. 37c, 193—198 (1982); received November 2 December 1 1981 
  Published    1982 
  Keywords    Rhodopseudomonas capsulata, Purification, Solubilization, Cytochrome c, Cytochrome Oxidase, 6-Type Cytochrome 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-0193.pdf 
 Identifier    ZNC-1982-37c-0193 
 Volume    37