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1Author    Omer SayginRequires cookie*
 Title    Nonenzymatie Formation of Energy Rich Phosphates in the Course of Imidazole Oxidation with Fenton's Reagent  
 Abstract    Oxidation of substituted imidazoles with modified Fenton's reagent (Fe(II), ascorbic acid, EDTA and H2O2) in aqueous solution at pH 5-7 in the presence of inorganic ortho-phosphate gives high yields of an unknown bound phosphate, in the case of 2-methyl-imidazole up to 35% based on inorganic phosphate. The dependence of the yields on reaction parameters and the hydrolytic behaviour of the compound was studied. The products are unstable in alkaline medium and fairly stable in acid solution (half-life period ca. 1 h at 25 °C in IN perchloric acid). Similar bound phosphate was also observed using autoxidation with O2 instead of H2O2. 
  Reference    Z. Naturforsch. 35b, 1009—1014 (1980); received February 29 1980 
  Published    1980 
  Keywords    Bioids, Oxidative Phosphorylation, Photophosphorylation, Fenton's Reaction, Imidazole Oxidation 
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 TEI-XML for    default:Reihe_B/35/ZNB-1980-35b-1009.pdf 
 Identifier    ZNB-1980-35b-1009 
 Volume    35 
2Author    G. Schäfer, A. Trebst, K. H. BüchelRequires cookie*
 Title    2-Anilino-1.3.4-thiadiazole, Hemmstoffe der oxidativen und photosynthetischen Phosphorylierung 2-Anilino-l,3,4-Thiadiazoles, Inhibitors of Oxidative and Photosynthetic Phosphorylation  
 Abstract    2-anilino-l,3,4-thiadiazoles carrying various substituents in the 5-position as well as in the benzene-ring were synthesized. The compounds were tested with rat-liver-mitochondria and with spinach-chloroplasts and revealed to be potent uncouplers of both, oxidative and photosynthetic phosphorylation, with p l50-values rangeing from 6.79 to 4.05. At higher concentration all compounds are inhibitors of the Hill-reaction. In mitochondria a fair correlation exists between pKa of the acidic NH-group and the un­ coupling activity; a maximum is obtained around pKa= 6 .8 , whereas in chloroplasts activity is shifted to more acid pKa-values. The compounds meet the requirements for uncouplers according to the chemi-osmotic theory, being lipophilic weak acids. N-methylation causes total loss of activity in mitochondrial oxidative phosphorylation. The inhibitory action on photosynthetic electron transport is located within photosystem II. This latter activity is almost independent of substituent effects in contrast to uncoupling of either respiratory-or photo-phosphorylation. 
  Reference    (Z. Naturforsch. 30c, 183 [1975]; eingegangen am 19. Dezember 1974) 
  Published    1975 
  Keywords    Oxidative Phosphorylation, Photophosphorylation, Uncouplers, Structure-function Correlation 
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 TEI-XML for    default:Reihe_C/30/ZNC-1975-30c-0183.pdf 
 Identifier    ZNC-1975-30c-0183 
 Volume    30 
3Author    Götz Harnischfeger, Reinhard SchopfRequires cookie*
 Title    A Fluorescence Method for Measuring the Retention of Coupling Factor (CFj) in Reconstitution Experiments of Photophosphorylation  
 Abstract    The recombination of chloroplast coupling factor 1 (CFj) and thylakoid membranes in reconsti­ tution experiments was studied through the fluorescence of paired labels covalently bound to NH,-groups. It was found that maximum recombination is achieved at a ratio of 1.5 —3,ag CF tl/ug chlorophyll. The addition of chloroplast lipids to the medium enhances the incorporation of CFt into the membranes. The rates of ATP formation of the regenerated but labeled system are decreased to 50% of those found in unlabeled control experiments. This is discussed in context with the previous observation, that labeling of CFX at similar concentrations inhibits the ATPase activity of the isolated protein completely. The possible use of double labeling in the study of the physical aspects of the reconstitution of the photophosphorylating system is discussed. 
  Reference    (Z. Naturforsch. 32c, 392 [1977]; received January 26/February 16 1977) 
  Published    1977 
  Keywords    Fluorescence Label, Coupling Factor 1, Reconstitution, Photophosphorylation 
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 TEI-XML for    default:Reihe_C/32/ZNC-1977-32c-0392.pdf 
 Identifier    ZNC-1977-32c-0392 
 Volume    32 
4Author    J.J S Van Rensen, J. H. HobéRequires cookie*
 Title    Mechanism of Action of the Herbicide 4,6-Dinitro-o-cresol in Photosynthesis  
 Abstract    The herbicide 4,6-dinitro-o-cresol inhibits electron transport to ferricyanide and non-cyclic photophosphorylation for 50% at about 15 /am. At higher concentrations the photosystem I depen­ dent M ehler reaction ascorbate/dichlorophenolindophenol to m ethyl viologen is stim ulated, while cyclic photophosphorylation is inhibited. The herbicide thus is an inhibitory uncoupler. A lthough the chemical structure of 4,6-dinitro-o-cresol is different from th a t of the diuron-type herbicides, its site and mechanism of action is similar. Both 4,6-dinitro-o-cresol and diuron inhibit electron transport between the prim ary electron acceptor of Photosystem II and the plastoquinone pool. This causes a closing of the reaction centers of Photosystem II. The interaction with the inhibited molecule however is different for the two herbicides. 
  Reference    Z. Naturforsch. 34c, 1021 (1979); received May 26 1979 
  Published    1979 
  Keywords    Photosynthesis, Electron Transport, Photophosphorylation, H erbicides 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-1021.pdf 
 Identifier    ZNC-1979-34c-1021 
 Volume    34 
5Author    G. Erard Van Den Berg, M. Arjo, B. Randse, Jaco, T. Ip, D. U. Ph, A.R B VRequires cookie*
 Title    Effects of Substituted 2-Phenylamino-l,4,5,6-tetrahydropyrimidines on ATP Formation in Isolated Spinach Chloroplasts  
 Abstract    The effects o f a series o f 2-arylam ino-l,4,5,6-tetrahydropyrim idines on photosynthesis in spin­ ach chloroplast were studied. The com pounds proved to be uncouplers o f photophosphorylation, while inhibition o f electron transport occurred at higher concentrations. These effects were rather irreversible and the activity increased with lipophilicity. Inhibition o f electron transport could not be reversed by trypsin treatmeni. Loss o f membrane integrity m ight be the underlying m echanism o f these effects. 
  Reference    Z. Naturforsch. 37c, 651—657 (1982); received April 2 1982 
  Published    1982 
  Keywords    Arylaminopyrimidines, Photophosphorylation, Electron Transport, Chloroplasts, uncouplers 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-0651.pdf 
 Identifier    ZNC-1982-37c-0651 
 Volume    37 
6Author    Bernhard HuchzermeyerRequires cookie*
 Title    Energy Transfer Inhibition Induced by Nitrofen  
 Abstract    The herbicide nitrofen was shown to act as an energy transfer inhibitor. The results proved nitrofen to act by inhibiting nucleotide exchange on the chloroplast coupling factor. A strong correlation was found between the inhibition o f phosphorylation, ATPase activity, and nucleotide exchange. These results are discussed in terms of a regulatory effect o f tightly bound A D P on the enzymatic activity o f the chloroplast coupling factor. 
  Reference    Z. Naturforsch. 37c, 787—792 (1982); received April 30/June 8 1982 
  Published    1982 
  Keywords    Herbicides, Nitrofen, Energy Transfer Inhibition, Photophosphorylation, N ucleotide Exchange 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-0787.pdf 
 Identifier    ZNC-1982-37c-0787 
 Volume    37 
7Author    G. O., G. S. Chäfer, H. S. Tro, Tm AnRequires cookie*
 Title    Synthesis of 2'-/3'-0-Acylated Adenine Nucleotide Analogs and Their Interactions in Photophosphorylation  
 Abstract    By mono esterification o f 3'(2')-hydroxyl residues o f adenine nucleotides with various carb-oxylic acids a series o f nucleotide analogs is available including fluorescent and photoaffinity labels. Their chemical synthesis is described. The equilibrium between 2' and 3' esters is determined by N M R spectroscopy, stability o f the esters and their tendency o f acyl migration is discussed. The interaction o f the A D P derivatives with the chloroplast ATP synthesizing system is in­ vestigated. Actually, the analogs are typical energy transfer inhibitors, strongly inhibiting photo­ phosphorylation and concom itant coupled electron transport (ci50 values ranging from 0.3 to 85 |iM). On the basis o f inhibitory activities o f analogs bearing varying 3'-(2')-substituents, struc-ture-activity relationships are discussed. The inhibitory properties o f the em ployed A D P analogs are based on their specific interaction with the catalytic AD P binding site o f CF] and their extrem ely slow phosphorylation on the enzyme (rate 0.25% or less com pared to A D P phosphorylation). Inhibition is com petitive to AD P but non-com petitive with regard to P; . It is specific for the A D P derivatives, whereas the corresponding ATP analogs are only weak inhibitors in phosphorylation and the AMP derivatives are com pletely inactive. In light-triggered ATP hydrolysis, however, the ATP analogs exhibit an even stronger com petitive inhibition than the A D P derivatives. The results suggest that a conformational change o f ATPase takes place when the chloroplasts are transferred from energized to de-energized conditions which greatly affects the properties o f the active site with respect to nucleotide binding. In tro d u c tio n 
  Reference    Z. Naturforsch. 38c, 49 (1983); received October 7 1982 
  Published    1983 
  Keywords    N ucleotide Analogs, Photophosphorylation, Energy Transfer Inhibition 
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 TEI-XML for    default:Reihe_C/38/ZNC-1983-38c-0049.pdf 
 Identifier    ZNC-1983-38c-0049 
 Volume    38 
8Author    Berg, M. Arjo, Brandse Duphar, B. V. BiochemistryRequires cookie*
 Title    G erard van den  
 Abstract    The effects of the algicide PH 40-62 on photosynthetic reactions in spinach chloroplasts were studied. The compound proved to be an uncoupler o f photophosphorylation, whereas inhibition of photosynthetic electron transport occurred at higher concentrations. The site of this inhibition was before photosystem II. The uncoupling effect was partially reversible. In a series o f related compounds the uncoupling activity appeared mainly dependent on the lipophilic properties o f the compounds but electronic effects also played a distinct role. C om paring these uncoupling data with those of some known series of uncouplers it appeared that lipophilicity determ ines the uncoupling activity in an identical way and a regression equation was found describing the uncoupling activities of 60 compounds belonging to four chemically different groups of com ­ pounds. 
  Reference    Z. Naturforsch. 39c, 107—114 (1984); received Septem ber 19 1983 
  Published    1984 
  Keywords    Arylethanediamines, Photophosphorylation, U ncouplers, Structure-Activity Relationships 
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 TEI-XML for    default:Reihe_C/39/ZNC-1984-39c-0107.pdf 
 Identifier    ZNC-1984-39c-0107 
 Volume    39 
9Author    RichardJ. Berzborn, Werner FinkeRequires cookie*
 Title    Localization and Orientation of Subunit Delta of Spinach Chloroplast ATP-Synthase within the CF0CF! Complex 1. Distinction of Shielded and Exposed Surfaces of Delta on the Thylakoid Membrane  
 Abstract    A new polyclonal antiserum against spinach CF, subunit delta was produced in rabbits. It decorates only one band at 21 kDa in Western immunoblots of thylakoid proteins and does not react in E LISA with 6-free four subunit C F ,(—6); therefore it is regarded monospecific. The polypeptide used as immunogen had been purified by HPLC. Earlier antisera against CF, 6 cross-react with CF, subunit ß. The new antiserum 306 contains different antibodies; some can be absorbed with thylakoids, i.e. by 6 within the assembled CF0CF, complex on the membrane, others still react in ELISA with isolated CF,. The former antibodies agglutinate thylakoids and inhibit PMS cyclic photophos­ phorylation. Therefore we conclude that part of the surface of CF! subunit 6 is exposed within the quaternary structure of the ATP-synthase complex of photosynthetically active thylakoids, but part of the surface of 6 is shielded. Trypsination of isolated 6 occurs at several sites, but this protease does not attack 6 in situ, nor does aminopeptidase. Staphylococcus aureus protease V8 digests CF, 6 after isolation at residues Asp53, G1u61, G1u95 and G lu 106, but has no access to these residues of 6 in situ. Thus CF, subunit 6 seems to be shielded within the CF0CF, complex to a large degree. Direct agglutination of thylakoids by anti 6 serum 306 was weak and could be improved tenfold by a Coombs serum (goat anti rabbit gammaglobulin), whereas an anti ß serum agglutinated directly. From this we conclude that 6 is not accessible at the top of the enzyme; the exposed part is extending below the large subunits a and ß and oriented towards the membrane. 
  Reference    Z. Naturforsch. 44c, 153 (1989); received June 24/October 7 1988 
  Published    1989 
  Keywords    Accessibility, Antibodies, Coupling Factor, Proteolysis, Photophosphorylation 
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 TEI-XML for    default:Reihe_C/44/ZNC-1989-44c-0153.pdf 
 Identifier    ZNC-1989-44c-0153 
 Volume    44 
10Author    Teresa Maria, B. Gutiérrez-Lugo3, Amelia Las Lotina-Hennsenb, Sergio Farrésc, Rachel Sánchezd, Mata3Requires cookie*
 Title    Phytotoxic and Photosynthetic Activities of Maduramicin and Maduramicin Methyl Ester  
 Abstract    The polyether antibiotic maduramicin and its methyl ester derivative inhibited photophos­ phorylation and proton uptake in isolated spinach chloroplasts. Both compounds also en­ hanced basal and phosphorylating electron transport and stimulated Mg2+-dependent A T­ Pase activity, therefore, they behave as uncouplers of photophosphorylation being the methyl ester derivative more potent than the parent compound. On the other hand, maduramicin inhibited germination and radicle elongation of several crop and weed species. In addition, the antibiotic caused phytotoxic injury and fresh weight reduction to 4-to-6 week old seed­ lings of two weed and two crop species when applied at 1 0 ~ 4 m by foliar application in the greenhouse. 
  Reference    Z. Naturforsch. 54c, 325—332 (1999); received October 21/December 23 1998 
  Published    1999 
  Keywords    Maduramicin, Photophosphorylation, Uncoupler, Phytotoxicity, Polyether Antibiotic 
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 TEI-XML for    default:Reihe_C/54/ZNC-1999-54c-0325.pdf 
 Identifier    ZNC-1999-54c-0325 
 Volume    54 
11Author    Christoph GierschRequires cookie*
 Title    Photophosphorylation by Chloroplasts: Effects o f Low Concentrations o f Ammonia and Methylamine  
 Abstract    Intact chloroplasts exposed to hypotonic assay conditions are capable o f photophosphorylating exogenous ADP. The rate o f phosphorylation by these unbroken plastids is increased by 10—50% upon the addition o f low concentrations (< mM) o f N H 3 or C H 3 N H 2. Stimulation o f phosphory­ lation is abolished by washing chloroplasts with MgCl2. Evidence is presented that washing re­ moves a factor responsible for amine-induced increase o f A T P production and that this factor is associated with the thylakoid membrane. Addition o f CH3 N H 2 increased the proton permeability of the thylakoid membrane o f unbroken and washed chloroplasts during the light/dark transition. Hence, differences o f the membrane permeability for protons between the two preparations seem not to be responsible for an increase o f A T P production upon the addition o f amines. Stimulation of photophosphorylation by methylamine is observed even at light itensities which do not saturate the proton motive force, which in turn is reduced upon the addition o f the uncoupler. Apparently, phosphorylation can be stimulated, although the limiting driving force is diminished. It is con­ cluded that phosphorylation by unbroken chloroplasts under low light illumination is limited kinetically, not energetically. Consequences o f these findings for observation made with intact chloroplasts are discussed. 
  Reference    Z. Naturforsch. 37c, 242—250 (1982); received December 23 1981 
  Published    1982 
  Keywords    Photophosphorylation, Uncoupling, Amines, Proton Motive Force, Chloroplasts, Chemiosmotic Theory 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-0242.pdf 
 Identifier    ZNC-1982-37c-0242 
 Volume    37 
12Author    Bernhard Huchzermeyer, Andreas LöhrRequires cookie*
 Title    Diphenyl Ether Herbicides, a Tool to Elucidate the Mechanism of Photophosphorylation  
 Abstract    At least two different classes of A DP binding sites on chloroplast coupling factor are de­ scribed in the literature. High-affinity sites are assumed to entail regulatory functions while low-affinity sites are involved in catalysis. Diphenyl ether herbicides, acting as energy transfer inhibitors, interfere with nucleotide ex­ change on both categories of A D P binding sites. Their inhibitory potency varies depending on their substitution. We found that each diphenyl ether assayed revealed identical / 50 values for inhibition of nucleotide interaction with both classes of binding sites. We show here that diphenyl ether inhibition of energytransfer is primary based upon the interference with A DP binding to high-affinity binding sites. Thereby the control of proton permeability through the coupling factor complex is affected. Moreover, we found that the three ß-subunits are not absolutely fixed in one conformational state: After covalently block­ ing the high-affinity site by an azido-label, a new ß-subunit. 
  Reference    Z. Naturforsch. 45c, 552—557 (1990); received October 10 1989 
  Published    1990 
  Keywords    Diphenyl Ethers, Energy-Transfer Inhibition, Nitrofen, Photophosphorylation, Coupling Factor 
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 TEI-XML for    default:Reihe_C/45/ZNC-1990-45c-0552.pdf 
 Identifier    ZNC-1990-45c-0552 
 Volume    45 
13Author    GabrieleG. Ünther, Henrik LaaschRequires cookie*
 Title    Local Anesthetic Binding to Thylakoid Membranes. Relation to Inhibition of Light-Induced Membrane Energization and Photophosphorylation  
 Abstract    The association o f the lipophilic tertiary amine and local anesthetic dibucaine with osm oti-cally shocked chloroplasts o f Spinacia oleracea L. cv. M onatol was investigated. Dibucaine, known as an effective inhibitor o f thylakoid membrane energization and A TP synthesis, ex­ hibited three distinct binding classes with chloroplasts: partitioning in the lipid phase o f the membranes, electrostatic screening o f negative electrical charges on the thylakoid surface and light-induced association o f an as yet unknown nature. Evidence is presented that the mecha­ nism o f inhibition o f the transthylakoid pH gradient, ApH, by dibucaine is distinct from 'clas­ sical' amine-type uncoupling: The inhibitory effect o f dibucaine on ApH was independent o f the initial strength o f ApH. Light-induced dibucaine binding was independent o f the volum e o f the intrathylakoid space and o f the strength o f ApH as varied by medium pH. Judged from a comparison o f the data on dibucaine binding and on inhibition o f ApH and photophosphory­ lation, dibucaine bound via partitioning in the membrane lipid phase is responsible for the un-coupler-like effects o f the local anesthetic. A mechanism for the inhibition o f thylakoid energi­ zation by local anesthetic amines is discussed. 
  Reference    Z. Naturforsch. 46c, 79—8 (1991); received September 21 1990 
  Published    1991 
  Keywords    Chloroplast, Local Anesthetic, Dibucaine, Uncoupling, Photophosphorylation, Amine Bind­ ing 
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 TEI-XML for    default:Reihe_C/46/ZNC-1991-46c-0079.pdf 
 Identifier    ZNC-1991-46c-0079 
 Volume    46 
14Author    Henrik LaaschRequires cookie*
 Title    Maintenance of Photophosphorylation Despite Inhibition of the Transthylakoid pH Gradient by Tetracaine  
 Abstract    The inhibition o f the transthylakoid pH gradient, ApH, and o f photophosphorylation by the local anesthetic tetracaine was investigated with isolated chloroplasts from Spinacia olera-cea L. Tetracaine strongly inhibited ApH in the presence o f low salt concentrations. In the presence o f high salt concentrations, the inhibition o f ApH was much smaller. This effect o f salt concentration was observed only when both, cation and anion were easily membrane permeable. It was concluded that the effect o f salts on ApH inhibition was excerted on the inside o f the thylakoid membrane. The rate o f photophosphorylation, Vv, driven by the PS I-dependent artificial proton carrier phenazine methosulfate decreased with ApH in the presence o f both, high and low salt concentrations. In contrast, Vp driven by the endogenous proton pumps o f PS II + I-dependent linear electron flow was largely independent o f ApH changes in the presence o f low salt concentration. It appeared that energy coupling during linear electron transport, in contrast to artificially produced PS I-dependent coupling, may be localized to membrane-bound proton dom ains which are not accessible to the employed indicators o f ApH. The data were discussed with respect to recent hypotheses on localized energy coupling in chloroplasts. 
  Reference    Z. Naturforsch. 47c, 717 (1992); received June 26 1991/February 17 1992 
  Published    1992 
  Keywords    Photophosphorylation, Energy Coupling, Local Anesthetic, Tetracaine, Salt Concentrations, Localized Protons 
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 TEI-XML for    default:Reihe_C/47/ZNC-1992-47c-0717.pdf 
 Identifier    ZNC-1992-47c-0717 
 Volume    47 
15Author    N. Orbert, G. Rotjohann, David Messdaghi, Wolfgang KowallikRequires cookie*
 Title    Oxygen Uptake during Photosynthesis of Isolated Pea Chloroplasts  
 Abstract    Mass spectrometric analysis of the gas exchange of illuminated leaflets of 10-14 d old pea seedlings revealed not only 160 2-liberation from photosynthetic H2160-splitting, but also uptake of ls0 2, applied to the gas phase of the reaction vessel. Isolated intact chloroplasts of such leaflets suspended in a medium containing N aH C 03 and glycerate 3-phosphate, on irradiation with blue (A. 448 nm) or red (X 679 nm) light also produced 160 2 from water oxidation and consumed 180 2 from the gas phase. The two reactions were saturated at the same quantum fluence rates. Uptake of 18oxygen was not affected by inhibitors of mito­ chondrial respiration (alternative pathway included), such as rotenone (5 x l0 -5 m), antimycin A (5 x l0 ~6 m), KCN (10-3 m), SHAM (10-3 m), or propylgallate (10-3 m). It was, however, absent, when photosynthetic 16oxygen evolution was completely inhibited by DCMU (10-? m). DBMIB (10~5 m), assumed to prevent electron flow from plastoquinone pool to the cyto­ chrome ö6//-complex, suppressed photosynthetic oxygen evolution, but did not impair uptake of 180 2. A similar result was obtained at application of 4 x l0 _e; m antimycin A. The data are interpreted to show a drain off to molecular oxygen of light-excited electrons from the photosynthetic electron transport chain at the site of plastoquinone pool during photosynthesis. This corresponds to chlororespiration, originally described for Chlamydomo-nas in darkness by Bennoun (1982). It is discussed, whether 0 2-uptake during photosynthesis is an additional means for providing ATP for photosynthetic C 0 2-reduction by increasing the proton gradient across the thylakoid membrane. 
  Reference    Z. Naturforsch. 54c, 209—219 (1999); received October 5/November 13 1998 
  Published    1999 
  Keywords    Pisum sativum, Chlororespiration, 18Oxygen Consumption, Photophosphorylation, Intact Isolated Chloroplasts 
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 TEI-XML for    default:Reihe_C/54/ZNC-1999-54c-0209.pdf 
 Identifier    ZNC-1999-54c-0209 
 Volume    54 
16Author    Omer Say, Peter DeckerRequires cookie*
 Title    An Energy Rich Phosphate from 2 -Methylimidazole through Nonenzymatic Photophosphorylation * 4 * *  
  Reference    Z. Naturforsch. 38b, 1098—1100 (1983); received March 28 1983 
  Published    1983 
  Keywords    Bioids, Photophosphorylation, Imidazole Oxidation, Nonenzymatic Phosphate Activation, 4, 5-Dihydroxy-2-methylimidazoline-0-mono phosphate 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-1098.pdf 
 Identifier    ZNB-1983-38b-1098 
 Volume    38 
17Author    AugustoF. Garcia, G.Erhart DrewsRequires cookie*
 Title    Properties of Membrane Fractions Prepared by Chromatophore-Liposome Fusion  
 Abstract    Intracytoplasmic membrane vesicles (chromatophores) isolated from Rhodopseudomonas capsulata cells were fused with liposom es by a pH transition procedure. Vesicles o f lower density and higher lipid contents and larger diam eter than chrom atophores were obtained. Similar results were observed by Ca2+ induced fusion and by the freeze-thawing method. Respiratory and light-induced electron transport were m easured in chrom atophores and fused vesicles. Light-induced reaction center bleaching was observed in all types o f vesicles, whereas repiratory electron transport was substantially dim inished by lipid incorporation. U biquinone 10 restored to some extent respiratory electron transport and oxidative phosphorylation and it m odified the photophosphorylation kinetics under continuous light. Electrochrom ic carotenoid band-shift and the 9-aminoacridine fluorescence quenching indicate that the capacity o f the fused vesicles to maintain an electrochemical proton gradient has not been substantially dim inished. From the kinetics o f 9-aminoacridine quenching an increased K+-perm eability seem s to be apparent. 
  Reference    Z. Naturforsch. 39c, 1112—1119 (1984); received July 23 1984 
  Published    1984 
  Keywords    Photosynthetic Apparatus, Respiratory Chain, Rhodopseudom onas capsulata, M embrane Fusion, Liposomes, Photophosphorylation 
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 TEI-XML for    default:Reihe_C/39/ZNC-1984-39c-1112.pdf 
 Identifier    ZNC-1984-39c-1112 
 Volume    39