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1Author    Friederike Koenig, Wilhelm Menke, Hans Craubner, GeorgH. Schmid, Alfons RadunzRequires cookie*
 Title    Photochemically Active Chlorophyll-Containing Proteins from Chloroplasts and their Localization in the Thylakoid Membrane  
 Abstract    After solubilization of stroma-freed chloroplasts with deoxycholate, the lipids and the detergent used are separated from the proteins by gel filtration. In this way not denatured pigment-con-taining protein preparations were obtained. The particles in fraction 1 exhibited a molecular weight of 600 000 and contained an average of 25 chlorophyll molecules. The circular dichroism spectrum showed exciton splitting of the red band. The particles in fraction 2 contained 1 chloro-phyll molecule and exhibited a molecular weight of 110 000. The particles in fraction 3 also contained only 1 chlorophyll molecule and had a molecular weight of between 80 000 and 100 000. Pure preparations of fraction 1 only carried out the methylviologen M e h 1 e r reaction with the dichlorophenol indophenol/ascorbate couple as electron donor. Fraction 3 only reduced ferri-cyanide with diphenylcarbazide as an electron donor in the light. Fraction 2 exhibited both the photosystem I reaction and the photosystem II reaction. An antiserum to extracted fraction 1 does not inhibit electron transport in the intact lamellar system. The photoreduction of methylviologen is only inhibited after disruption of the thylakoids. The antiserum to fraction 2 inhibits the photo-reduction of methylviologen in the intact lamellar system. Consequently, one inhibition site for this photosystem I reaction must be located on the inner and another on the outer surface of the thylakoid membrane. In addition, antibodies to fraction 1 are specifically adsorbed onto the lamellar system without any effect on electron transport and without a concomitant agglutination. Antibodies to fraction 3 partially inhibit the photoreduction of ferricyanide with diphenylcarbazide as an electron donor in the intact lamellar system. Hence, the inhibition site of this system II reaction is located on the outer surface of the thylakoids. We have reason to believe that the inhibition sites not reacting are located in the partitions, which are not accessible to antibodies. 
  Reference    (Z. Naturforsch. 27b, 1225 [1972]; received July 5 1972) 
  Published    1972 
  Keywords    Chloroplasts, membranes, proteins, photosynthesis, antibodies 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-1225.pdf 
 Identifier    ZNB-1972-27b-1225 
 Volume    27 
2Author    A. Trebst, H. WietoskaRequires cookie*
 Title    Hemmung des photosynthetischen Elektronentransports von Chloroplasten durch Metribuzin * Mode of Action and Structure-Acitivity-Relationships of the Aminotriazinone Herbicide Metribuzin Inhibition of Photosynthetic Electron Transport in 'Chloroplasts by M etribuzin  
 Abstract    The influence of the aminotriazinone herbicide Metribuzin on photosynthetic reactions of iso­ lated chloroplasts is investigated. Metribuzin inhibits all Hill-reactions when water is the electron donor, but not photoreductions by photosystem I at the expense of an artificial electron donor. The PIso-value is 6.7. Cyclic photophosphorylation is not affected by Metribuzin. Measurements of the prompt and delayed fluorescence of the photosynthetically active chlorophyll support the notion, that Metribuzin inhibits photosynthetic electron flow between the primary and secondary electron acceptor of photosystem II (Q and plastoquinone). The relationship of inhibitory potency to chemical structure is investigated by comparing a number of related aminotriazinones. The effect of various substituents is discussed. E in le itu n g 
  Reference    (Z. Naturforsch. 30c, 499 [1975]; eingegangen am 7. April 1975) 
  Published    1975 
  Keywords    Photosynthesis, Chloroplasts, Herbicide, Metribuzin, Aminotriazinone 
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 TEI-XML for    default:Reihe_C/30/ZNC-1975-30c-0499.pdf 
 Identifier    ZNC-1975-30c-0499 
 Volume    30 
3Author    G. Kulandaivelu, D. 0. HallRequires cookie*
 Title    Stabilization of the Photosynthetic Activities of Isolated Spinach Chloroplasts during Prolonged Ageing  
 Abstract    Isolated spinach chloroplasts (type A complete) were used to study the changes in the pnoto-chemical activities upon storage in order to establish optimum conditions for prolonged storage. Chloroplasts stored at — 5 °C were found to retain over 70% of their photosynthetic electron transport from H20 even after 5 days. Increases in the level of state 2 electron transport (due to uncoupling) with concomitant loss of state 3 phosphorylation activity was observed during the initial period of ageing. Addition of 1% bovine serum albumin decreased the level of uncoupling and maintained the phosphorylation activity for a longer period. Chloroplasts stored at 77 °K main­ tained their phosphorylation capacity for a period of 10 days even after repeated freezing and thawing. Photosystem I activity was found to be more stable over the whole ageing period of 15 days. Loss of plastoquinone may be responsible for the decrease in electron transport between photosystems II and I. 
  Reference    (Z. Naturforsch. 31c, 452 [1976]; received August 22 1975/March 11 1976) 
  Published    1976 
  Keywords    Ageing, Stabilization, Photosynthetic Activities, Chloroplasts 
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 TEI-XML for    default:Reihe_C/31/ZNC-1976-31c-0452.pdf 
 Identifier    ZNC-1976-31c-0452 
 Volume    31 
4Author    Friederike Koenig, Alfons Radunz, GeorgH. Schmid, Wilhelm MenkeRequires cookie*
 Title    Antisera to the Coupling Factor of Photophosphorylation and Its Subunits  
 Abstract    Stroma-freed chloroplasts were extracted with sucrose palmitate-stearate containing buffer. A fter the addition o f dodecyl sulfate and mercaptoethanol to the extract a series of polypeptides was isolated from the mixture by gel filtration. These polypeptides were later used for immunization. Antisera to four polypeptides reacted in the Ouchterlony double diffusion test with authentic coupling factor yielding a precipitation band. According to the observed apparent molecular weights the polypeptides are the a, ß , 8 and e subunits of the coupling factor. An antiserum to the y subunit has been obtained already previously. A ll antisera inhibit photophosphorylation reactions and electron transport considerably. Addition of gramicidin inhibits photophosphorylation com pletely whereas gramicidin restores electron transport in the assays with the antisera to the a, ß , y and 5 subunit. In the case o f the antiserum to the E subunit gramicidin does not regenerate electron transport. As in the presence of the serum to the £ subunit pH changes in the suspension medium are not observed, this serum seems to open a proton channel. Also, upon addition of dicyclohexyl carbodiimide (D C C D) pH changes in the suspension medium in the assay with antiserum do not reoccur. According to these unexpected results the identity o f the antigen with the e subunit of the coupling factor is not certain. ATP-ase reactions are only inhibited by the antisera to the a and y subunit and what is thought to be the £ subunit. The antiserum to the a subunit uncouples electron transport as the only one when used in sufficient concentrations. The dosis-effect curves o f the inhibition of the electron transport exhibits a maximum. The dosis-effect curves for the other components rise after a lag phase in an approxim ately hyperbolic manner. The inhibitory action on electron transport is exerted by all antisera in the region of the reaction center I or in its immediate vicinity. This is thought to be due to the fact that a protein of the reation center I is inhibited in its function by the increasing proton concentration inside the thylakoid. The inhibition of electron transport by the antiserum to the e subunit is considered to be a direct serum effect. Besides the increase in fluorescence yield, due to the inhibition of electron transport in the region o f photosystem I, decreases of the fluorescence yield are observed in the presence of D CM U, which do not depend on the redox state of Q but rather on the condition of the thylakoid mem­ brane. Moreover, the antisera affect in a differing manner the energy spill-over o f excitation from photosystem I I to photosystem I. 
  Reference    Z. Naturforsch. 33c, 529 (1978); received June 21 1978 
  Published    1978 
  Keywords    Coupling Factor, Antisera, Chloroplasts, Fluorescence 
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 TEI-XML for    default:Reihe_C/33/ZNC-1978-33c-0529.pdf 
 Identifier    ZNC-1978-33c-0529 
 Volume    33 
5Author    H. K. KleudgenRequires cookie*
 Title    Veränderungen der Pigment-und Prenylchinongehalte in Chloroplasten von Gerstenkeimlingen nach Applikation des Wuchsstoffherbizids MCPA (4-Chlor-2-methylphenoxyessigsäure) Changes of the Amounts of Pigments and Prenylquinones in Chloroplasts of H ordeum vulgare — Seedlings Treated with the Growth Regulating Herbicide MCPA (4-Chloro-2-methylphenoxyacetic Acid)  
 Abstract    MCPA (4-chloro-2-methylphenoxyacetic acid) was applied (1, 10, 100 ^ m/ 1) via the roots to 4 day old etiolated barley seedlings, which were subjected to continuous white light at the same time. The prenyllipids of chloroplasts (chlorophylls, carotenoids, prenylquinones) were determined 7 and 10 days after sowing. Chlorophyll accumulation was reduced by up to 40% compared to the control depending on the herbicide concentration. The formation of carotenoids was inhibited to a lower degree, the ratio xanthophylls/carotenes being increased. There were decreasing ratios of chlorophyll a/benzoquinones and a higher inhibition of the oxidized benzoquinones plastoquinone-9 and a-tocoquinone compared to the reduced forms plastohydroquinone-9 and a-tocopherol. Very similar changes had been observed in earlier works on barley seedlings undergoing an artificial degeneration of their chloroplasts in the dark. It is suggested that MCPA induces a state of senescence in the prenyllipid metabolism of the photosynthetic apparatus, which is cor­ related with respect to structure, to a reduction of the pigment antennae. 
  Reference    Z. Naturforsch. 34c, 106 (1979); eingegangen am 13. November 1978 
  Published    1979 
  Keywords    Growth-Regulator, Prenyllipids, Chloroplasts, Senescence 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0106.pdf 
 Identifier    ZNC-1979-34c-0106 
 Volume    34 
6Author    H. K. KleudgenRequires cookie*
 Title    Die Wirkung von Simazin auf die Bildung der plastidären Prenyllipide in Keimlingen von Hordeum vulgare L. Effect of Simazine on Formation of Chloroplasts Prenyllipids in Seedlings of H ordeum vulgare L  
 Abstract    Barley seedlings were grown for 7, 10 or 13 days under continuous white light (Fluora lamps) on a nutrient solution containing simazine (2-chloro-4,6-bis-(ethylamino)-s-triazine, 10, 100 j u m) . Accumulation of chlorophylls and in part of carotenoids was increasingly enhanced depending on age and concentrations applied. The ratio chlorophyll a/b decreased on this line in 10 and 13 day old plants, the ratio xanthophylls//?-carotene and the ratio chlorophyll a/prenylquinones (plasto-quinone-90x. + red. , a-tocopherol, a-tocoquinone) increased. The way how these prenyllipid ratios are changed in 10 and 13 day old plants is characteristic of a shade type adaptation, as it was shown earlier for other herbicides inhibiting photosystem II. In 7 day old plants the ratio chlorophyll a/prenylquinones decreased. Photosynthetic activity (Hill-reaction) was enhanced in the simazine plants. The ratio chlorophyll a/b was higher, the ratio xanthophylls//?-carotene was lower than in the older seedlings. Similar changes of prenyllipid ratios like in 7 day seedlings and a higher Hill activity were also found in plants grown under blue light (sun type adaptation) as compared to red light (shade type adaptation). This points to similar metabolic changes in the chloroplasts which could be related to a common site of regulation, perhaps the endogenuous cytokinins. The Hill activity, increasing with age in the 10 and 13 day plants, indicates that the mode of action of simazine may be a multiple process resulting to a parallel formation of shade type and sun type characteristics. 
  Reference    Z. Naturforsch. 34c, 110 (1979); eingegangen am 13. November 1978 
  Published    1979 
  Keywords    Herbicide, Simazine, Prenyllipids, Chloroplasts, Regulation 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0110.pdf 
 Identifier    ZNC-1979-34c-0110 
 Volume    34 
7Author    GeorgH. Schmid, Pierre ThibaultRequires cookie*
 Title    Evidence for a Rapid Oxygen-Uptake in Tobacco Chloroplasts  
 Abstract    A fast oxygen uptake, induced by a sequence of short (5 /usee) saturating flashes was observed in chloroplasts of wild type tobacco and two chlorophyll-deficient tobacco mutants. One of the chlorophyll mutants is the earlier described variegated tobacco NC 95. Chloroplasts of this mutant exhibit only photosystem I mediated photoreactions, hence the observed oxygen uptake is to be associated with photosystem I. This is further substantiated by the fact that the oxygen uptake is insensitive to DCMU in the two chloroplast types used, which have both photosystems fully func­ tioning. The uptake depends on the addition of electron acceptors like p-benzoquinone in intact chloroplasts or on p-benzoquinone or ferricyanide in chloroplasts that have lost the envelope. In dark adapted chloroplasts, therefore, under these conditions the overall apparent gas exchange in the first two flashes is consumption. Although the uptake is slower than photosynthetic oxygen evolution it clearly affects the oxygen yield in the flash sequences. This is demonstrated by several experiments in which the apparent oxygen consumption in the absence of DCMU oscillates with a periodicity of four. We have indications that in chloroplasts of the tobacco aurea mutant Su/su the oxygen uptake is faster than in wild type chloroplasts. 
  Reference    Z. Naturforsch. 34c, 414 (1979); received February 14 1979 
  Published    1979 
  Keywords    Chloroplasts, Oxygen uptake, Oscillations, Photosynthesis 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0414.pdf 
 Identifier    ZNC-1979-34c-0414 
 Volume    34 
8Author    Magdolna Droppa, Sándor Demeter, Zsuzsa Rózsa, G. Ábor HorváthRequires cookie*
 Title    Reinvestigation of the Effects of Disalicylidenepropanediamine (DSPD) and 2-HeptyM-hydroxyquinoline-N-oxide (HQNO) on Photosynthetic Electron Transport  
 Abstract    The effects of disalicylidenepropanediamine (DSPD) and 2-heptyl-4-hydroxyquinoline-N-oxide (HQNO) on photosynthetic electron transport have been reexamined. The results confirm earlier observations that lower concentrations of DSPD (< 100 hm) block electron transport at the levels of ferredoxin and plastocyanin. High concentrations o f DSPD even inhibit electron transport from HaO -> pBQ, suggesting that DSPD has an inhibitory site in PS II as well. Thermoluminescence curves o f DSPD and DCMU treated chloroplasts were very similar, showing that the third inhibitory site o f DSPD is similar to that o f DCMU. Both oxidized and reduced HQNO, (0 .6 -6 hm) blocked electron transport from H20 -* pBQ, H20 -*■ MV/FeCy to a similar extent. The effect of HQNO on thermoluminescence showed that its inhibitory site is probably located before that o f DCMU. At higher concentration (> 6 h m) , the H20 -*■ MV/FeCy reactions were more strongly inhibited by oxidized HQNO than those occuring from H20 -> pBQ, suggesting that a new site o f inhibition must also be considered. The dark decay of the P 700 signal was not influenced by the addition o f oxidized HQNO which shows that the new inhibitory site of HQNO is located between plastoquinone and P 700. The reduced form of HQNO did not inhibit non-cyclic electron transport around PS I. Indeed, at higher concentrations, reduced HQNO even accelerates electron flow from DCIP -» MV and the dark reduction of P 700, thus suggesting that this compound has a "donor-mediator" function in PS I. 
  Reference    Z. Naturforsch. 36c, 109 (1981); received September 8/October 28 1980 
  Published    1981 
  Keywords    Inhibitors, Electron Transport, Chloroplasts, Thermoluminescence 
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 TEI-XML for    default:Reihe_C/36/ZNC-1981-36c-0109.pdf 
 Identifier    ZNC-1981-36c-0109 
 Volume    36 
9Author    David Pan, KimH. TanRequires cookie*
 Title    Evidence for a Transcarboxylase Reaction in M aize Chloroplast Extracts  
 Abstract    The authors have suggested (Can. J. Bot. 49, 631 (1971) that the — COOH group of the C4-P carbonyl compound of the thermostable P-enolpyruvate acid carboxylase reaction may transcarboxylase with a pentose phosphate as ac­ ceptor. We now have considerable evidence supporting this consideration. In an assay system (0.8 ml) containing soni­ cated chloroplast extract in 0.1 m Tris-HCl, pH 6.3; and PEP, 0.1 |imol; Mg2+, 0.5 nmol; NADH, 0.25 nmol; sugar phosphate, 0.5 nmol. The amount of 14C 0 2 fixation is con­ siderably enhanced by either ribose-5-phosphate, fructose-1,6-bisphosphate or ribulose-l,5-bisphosphate in the pres­ ence of PEP. The products of the reaction include malate as a product of /?-carboxylation, and glycerate or 3-phosphate glycerate, their proportion being determined by the ac­ ceptor sugar phosphate. The results provide evidence for a "transcarboxylase" presented in the crude extract of Maize chloroplasts. 
  Reference    Z. Naturforsch. 36c, 688—691 (1981); received December 11 1980/February 27 1981 
  Published    1981 
  Keywords    Photosynthesis, Chloroplasts, C4 Plants, Transcarboxylase 
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 TEI-XML for    default:Reihe_C/36/ZNC-1981-36c-0688_n.pdf 
 Identifier    ZNC-1981-36c-0688_n 
 Volume    36 
10Author    Hans-Jürgen Tiburzy, RichardJ. BerzbornRequires cookie*
 Title    Subunit II (b') and Not Subunit I (b) of Photosynthetic ATP Synthases is Equivalent to Subunit b of the ATP Synthases from Nonphotosynthetic Eubacteria. Evidence for a New Assignment of b-Type F0 Subunits  
 Abstract    Subunit I of chloroplast ATP synthase is reviewed until now to be equivalent to subunit b of Escherichia coli ATP synthase, whereas subunit II is suggested to be an additional subunit in photosynthetic ATP synthases lacking a counterpart in E. coli. A fter publication of some sequences of subunits II a revision of this assignment is necessary. Based on the analysis of 51 amino acid sequences of b-type subunits concerning similarities in primary structure, iso­ electric point and a discovered discontinuous structural feature, our data provide evidence that chloroplast subunit II (subunit b' of photosynthetic eubacteria) and not chloroplast subunit I (subunit b of photosynthetic eubacteria) is the equivalent of subunit b of nonphoto­ synthetic eubacteria, and therefore does have a counterpart in e.g. E. coli. In consequence, structural features essential for function should be looked for on subunit II (b'). 
  Reference    Z. Naturforsch. 52c, 789—798 (1997); received August 1 1997 
  Published    1997 
  Keywords    Chloroplast, Coupling Factor, Stalk, Cyanobacteria 
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 TEI-XML for    default:Reihe_C/52/ZNC-1997-52c-0789.pdf 
 Identifier    ZNC-1997-52c-0789 
 Volume    52 
11Author    G. Uhlenbruck, A. RadunzRequires cookie*
 Title    Use of Heterophilic Agglutinins in Plant Serology  
 Abstract    In previous communications it has been demonstrat-ed that monogalactosyl diglyceride and the anionic chloroplasts lipids can be detected on the thylakoid membrane by specific antisera 1_3 . The antigen deter-minants are of carbohydrate nature as was shown by specific agglutination inhibition tests. They are located on the outer surface of the thylakoid membrane and are directly accessible to the antibodies. The latter has been proven for the monogalactolipid 1 , whereas the de-terminants having the carbohydrate structure like that of sulphoquinovosyl diglyceride 2 stick out of the sur-face like phosphatidyl glycerol too 3 , but are topogra-phically rather arranged in gaps or pores of the membrane. Fatty acids are not involved in this antigen-antibody reactions as precipitation studies with hydrat-ed lipids and with lipids of different fatty acid com-positions have revealed. On the other side, if sugar components represent the immunologically determinant groups, then it should be possible to confirm the results obtained with vertebrate antisera by using heterophilic agglutinins from plants (so-called lectins) 4 , inverte-brates and fish eggs. These are known to be excellent tools for the specific detection of terminal and inner-chain carbohydrate structures of different configurations and conformations 5 . As D-galactose is the main deter-minant sugar in plant glycolipids, we tested some of the galactose specific lectins in our system. It could be found, that the agglutinin from Ricinus communis, the anti-galactosyl specificity of which is well established 4 , agglu-tinated chloroplasts and thylakoidfragments in a very specific way. This agglutination was inhibited by 0.03 M D-galactose, 0.06 M lactose, raffinose, stachyose, mono-galactosyl glycerol (/9-glycosidic linkage), and digalac-tosyl glycerol (a-glycosidic linkage of D-galactose), but not by D-glucose, and L-arabinose. In addition, the spe-cific anti-a-galactosyl agglutinin 6 ("anti-B") from Salmo trutta (trout) also reacts well, especially after protease treatment. It is inhibited by carbohydrates with terminal a-glycosidic bound D-galactose (raffinose, stachyose, digalactosyl glycerol 0.03 M) and not by monogalactosyl glycerol, lactose, D-glucose, D-and L-arabinose. We got weaker reactions with agglutinins from fungal origin like Fomes fomentarius, a lectin known as anti-B (a-galactosyl) reagent 4 ' 7 , whereas other agglutinins (Arachis hypogoea "anti-T") directed to D-galactose-like structures 8 gave very weak 
  Reference    (Z. Naturforsch. 27b, 1113 [1972]; received June 27 1972) 
  Published    1972 
  Keywords    Heterophilic agglutinins, glycolipids, chloroplasts, thylakoids, lectins 
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 TEI-XML for    default:Reihe_B/27/ZNB-1972-27b-1113_n.pdf 
 Identifier    ZNB-1972-27b-1113_n 
 Volume    27 
12Author    A. Trebst, E. HarthRequires cookie*
 Title    Herbicidal N-Alkylated-Ureas and Ringclosed N-Acylamides as Inhibitors of Photosystem II  
 Abstract    The inhibitory action of some herbicides on photosynthetic electron flow at photosystem I I in isolated chloroplasts was investigated. Emphasis in the study is on compounds, whose chemical structure seemed to be in disaccordance with the basic structural element, proposed to be required for a photosystem II inhibitor. The effective inhibition of photosynthetic oxygen evolution by N-alkylated urea-, pyrrolidone-and by substituted pyridazine-derivatives without a free NH-group is reported. A revised basic chemical structural element responsible for inhibition is deduced in order to include lactames (ringclosed N-acylamides) with and without hetero atoms. From this new groups of potential inhibitors, like triazolone-, thiadiazolone-and oxadiazolone-derivatives may be conceived. 
  Reference    (Z. Naturforsch. 29c, 232 [1974]; received February 4 1974) 
  Published    1974 
  Keywords    Inhibitor, Herbicides, Photosynthesis, Photosystem II, Chloroplasts 
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 TEI-XML for    default:Reihe_C/29/ZNC-1974-29c-0232.pdf 
 Identifier    ZNC-1974-29c-0232 
 Volume    29 
13Author    ErichF. Elstner, Claus Stoffer, Adelheid HeupelRequires cookie*
 Title    Determination of Superoxide Free Radical Ion and Hydrogen Peroxide as Products of Photosynthetic Oxygen Reduction  
 Abstract    Formation of Nitrite from Hydroxylamine in the presence of illuminated chloroplast lamellae is inhibited by superoxide dismutase but not by catalase, indicating that the superoxide free radical ion and not H20 2 is responsible for the oxidation of hydroxylamine. Decarboxylation of a-keto acids on the other hand is strongly inhibited by catalase but only slightly by superoxide dismutase. Light-dependent hydroxylamine oxidation and decarboxylation of a-keto acids can be used, there­ for, as specific and sensitive probes for the determination of either the superoxide free radical ion or hydrogen peroxide, respectively. Photosynthetic oxygen reduction in the presence of ferredoxin, (monitored by the above method) yields both H20 2 and 0 2 ". The addition of an oxygen reducing factor (ORF, solubilized by heat — treatment of washed chloroplast lamellae) instead of ferredoxin, however, stimulates only the production of H20 2 , while 0 2'~ — formation is not observed. The cooperation of ferredoxin and ORF during photosynthetic oxygen reduction by chloroplast lamellae apparently produces H20 2 not only by dismutation of 0 2'~, but also by a separate mechanism involving ORF. yields only in the formation of H20 2 . The coopera­ tion of Fd and ORF in photosynthetic oxygen re­ duction provides a system which is able to produce HoOo and 0 2~ simultanuously. During photosyn­ thetic oxygen reduction, H 20 2 is not only the product of the dismutation of the superoxide free radical ion according to Eqn (1) 0 2'-+ Oo ~ + 2 H +-> H2Oo + 0 2 (1) but is separately formed by a mechanism which includes the function of ORF. Material and Methods Ferredoxin was isolated from spinach leaves9 and SOD from dried green peas 10, 5. Chloroplasts were isolated either from spinach 11 or from sugar beet leaves12' 7. ORF was prepared from isolated chloroplast lamellae 7 from either spinach or sugar beet leaves. Photosynthetic decarboxylation of [l-14C]gly-oxylate13, NADP-reduction13 and nitrite-forma-tion 14 from hydroxylamine were measured as de­ scribed. Sugar beet leaves (greenhouse cultures) were a gift from the Kleinwanzlebener Saatzucht AG, Einbeck/Hann. [1-14C] sodium glyoxylate was obtained from the Radiochemical Center, Amersham. Catalase was purchased from Boehringer, Mannheim. 
  Reference    (Z. Naturforsch. 30c, 53 [1975]; received October 25 1974) 
  Published    1975 
  Keywords    Chloroplasts, Oxygen Reduction, Hydroxylamine Oxidation, Superoxide Free Radical Ion 
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 TEI-XML for    default:Reihe_C/30/ZNC-1975-30c-0053.pdf 
 Identifier    ZNC-1975-30c-0053 
 Volume    30 
14Author    K. H. Grumbach, H. K. LichtenthalerRequires cookie*
 Title    Kinetic of Lipoquinone and Pigment Synthesis during Red Light-Induced Thylakoid Formation in Etiolated Barley Seedlings  
 Abstract    Red light induces in etioplasts of dark-grown barley seedlings (H ordeum vulgare L.) parallel to the formation of chlorophyll an increased synthesis of carotenoids, lipophilic benzoquinones and of vitamin Kt . 1. Among the carotenoids red light initiates an enhanced synthesis of /2-carotene, lutein, violaxanthine and neoxanthine whereas the pools of zeaxanthine and antheraxanthine are decreased. 2. The formation of plastoquinone-9, vitamin Kj and a-tocoquinone is more enhanced than that of a-tocopherol. 3. The red light-induced changes of carotenoid and lipoquinone metabolism are similar in a qualitative sense to those obtained under continuous far-red, white or blue light. 4. In contrast to blue light, red light induces in the first hours of illumination a lower rate of chlorophyll and vitamin Kt formation. There are also differences in the ratios of the individual pigments and lipoquinones throughout the greening period. 
  Reference    (Z. Naturforsch. 30c, 337 [1975]; received January 29 1975) 
  Published    1975 
  Keywords    Chloroplasts, Thylakoid Formation, Lipoquinones, Red Light, /?-Carotene 
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 TEI-XML for    default:Reihe_C/30/ZNC-1975-30c-0337.pdf 
 Identifier    ZNC-1975-30c-0337 
 Volume    30 
15Author    H.-H HenniesRequires cookie*
 Title    Die Sulfitreduktase aus Spinacia oleracea — ein Ferredoxin- abhängiges Enzym A Ferredoxin-linked Sulfite Reductase from Spinacia oleracea  
 Abstract    A sulfite reductase from spinach has been purified 125 fold. Throughout all stages of purification the reduction of sulfite has been found dependent on ferredoxin. Reduced ferredoxin has been provided either by photosynthetic reduction in isolated, broken chloroplasts or by NADPH via the ferredoxin-NADP-oxidoreductase. During the purification procedure ferredoxin as electrondonor has been replaced by reduced methylviologen. 
  Reference    (Z. Naturforsch. 30c, 359 [1975]; eingegangen am 17. März 1975) 
  Published    1975 
  Keywords    Sulfite Reductase, Sulfate Assimilation, Ferredoxin, Chloroplasts 
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 TEI-XML for    default:Reihe_C/30/ZNC-1975-30c-0359.pdf 
 Identifier    ZNC-1975-30c-0359 
 Volume    30 
16Author    Alfons RadunzRequires cookie*
 Title    Binding of Antibodies onto the Thylakoid Membrane I. Maximal Antibody Binding and Adsorption of Antibodies to Lipids  
 Abstract    The binding of antibodies onto the lamellar system of A ntirrhinum m ajus was determined in dependence on the serum addition. The unspecific adsorption of serum proteins was taken into account or eliminated. The binding of antibodies as a function of the amount of serum added is seen from a saturation curve. From an antiserum obtained by hyperimmunization with stroma-freed chloroplasts, the chloroplasts bind maximally 1 gram antibodies per gram stroma-freed chloro­ plasts. From an antiserum to the proteins of the thylakoid membrane prepared in the same way an equal amount of antibodies is adsorbed. It is assumed that with this amount the surface of the lamellar system accessible to antibodies is completely covered by antibodies. For an antiserum to monogalactosyl diglyceride a maximal antibody binding of 0.16 g, for sulphoquinovosyl diglyceride 0.12 g and for phosphatidyl glycerol 0.13 g of antibodies per gram stroma-freed chloroplasts are obtained. The significance of these results with respect to the molecular surface structure of the thylakoid membrane is discussed. 
  Reference    (Z. Naturforsch. 30c, 484—488 [1975]; received April 11975) 
  Published    1975 
  Keywords    Chloroplasts, Lipids, Proteins, Antibodies, Membrane Structure 
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 TEI-XML for    default:Reihe_C/30/ZNC-1975-30c-0484.pdf 
 Identifier    ZNC-1975-30c-0484 
 Volume    30 
17Author    Alfons RadunzRequires cookie*
 Title    Localization of the Tri-and Digalactosyl Diglyceride in the Thylakoid Membrane with Serological Methods  
 Abstract    Trigalactosyl diglyceride was isolated from leaves of Urtica dioica and characterized by thin layer chromatography, infrared spectroscopy and by its fatty acid composition. An antiserum to the trigalactolipid was obtained by immunization of rabbits. By means of inhibition experiments with oligosaccharides and mono-and digalactosyl glycerol it was demonstrated that the antibodies are directed towards the a-galactosyl-(1 -> 6) -a-galactosyl-(1 — ► 6) -/5-galactosyl-(1 -*■ 1) -glycerol con­ figuration of the trigalactosyl diglyceride. Monogalactosyl diglyceride and sulfoquinovosyl diglyce­ ride do not react with this antiserum. However, a cross reaction was observed with digalactosyl diglyceride. The presence of antibodies to tri-and digalactosyl diglyceride was demonstrated in antisera to different chloroplast preparations of Antirrhinum majus and Spinacia oleracea. The antiserum to the trigalactolipid agglutinates stroma-freed chloroplasts. Membrane fragments obtained by the ultra sonication were precipitated. The antiserum is exhausted by trigalactosyl di­ glyceride but not by digalactosyl diglyceride or digalactosyl glycerol. The antiserum treated with digalactosyl glycerol and digalactosyl diglyceride also agglutinated stroma-freed chloroplasts. 1 g stroma-freed chloroplasts binds 0.17 g antibodies to trigalactolipid. Membrane fragments bind more antibodies to trigalactolipids than stroma-freed chloroplasts. From the agglutination tests it follows that the antigenic determinants of the trigalactolipid and the digalactolipid are localized in the outer surface as well as in the surface directed towards the inside of the thylakoid membrane. 
  Reference    (Z. Naturforsch. 31c, 589 [1976]; received July 19 1976) 
  Published    1976 
  Keywords    Trigalactosyl Diglyceride, Digalactosyl Diglyceride, Antibodies, Chloroplasts, Thylakoid Membrane 
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 TEI-XML for    default:Reihe_C/31/ZNC-1976-31c-0589.pdf 
 Identifier    ZNC-1976-31c-0589 
 Volume    31 
18Author    Edward Göbel, Ruth Riessner, Peter PohlRequires cookie*
 Title    Einfluß von DCMU auf die Bildung von Lipiden und Fettsäuren und auf die Ultrastruktur von Euglena gracilis Influence of DCMU on the Formation of Lipids and Fatty Acids, and on the Ultrastructure of Euglena gracilis  
 Abstract    Euglena g racilis Klebs (strain Z) was grown heterotrophically in the dark for 6 days. Sub­ sequently, the cells were grown photoautotrophically under white fluorescent light with varying amounts of 3-(3,4-dichlorophenyl)-l,ldimethyl urea (DCMU) (1 .7 X 1 0 -9 — 1 .0 X 1 0 -5 mol/1) added 
  Reference    (Z. Naturforsch. 31c, 687 [1976]; eingegangen am 9. März/20. September 1976) 
  Published    1976 
  Keywords    Euglena gracilis, Fatty Acids, Lipids, Ultrastructure, Chloroplasts, Mitochondria 
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 TEI-XML for    default:Reihe_C/31/ZNC-1976-31c-0687.pdf 
 Identifier    ZNC-1976-31c-0687 
 Volume    31 
19Author    Bernd Schmidt, HansJ. RurainskiRequires cookie*
 Title    Light-Dependent Interactions of Phenazine Methosulfate with 3-(3,4-Dichlorophenyl)-l,l-dimethylurea-Poisoned Chloroplasts  
 Abstract    The chlorophyll fluorescence of isolated chloroplasts in the presence of phenazine methosulfate (PMS) and 3-(3,4-dichlorophenyl)-l,l-dimethylurea (DCMU) can be quenched in a light-dependent reaction. This phenomenan has been studied and the following observations were made: 1. Quenching occurs under non-phosphorylating conditions and is stimulated by Mg2+ ions. 2. Under the same conditions, a light-dependent, Mg2+ stimulated transient decrease of absorp­ tion at 388 nm is observed which shows the spectral characteristics of PMS. 3. PMS is reversibly bound to chloroplasts. Under the experimental conditions used, binding amounts to as much as 0.5 mol PMS/mol chlorophyll. 4. Some uncouplers of photophosphorylation such as carbonylcyanide-m-chlorophenylhydrazon (CCCP) and atebrin analog abolish quenching, transient absorption change and binding of PMS. Others, such as methylamine, ammonia, gramicidin and nigericin do not. It is suggested that fluorescence quenching, transient absorption change and binding of PMS are causally related. The concept, postulated by others, that a high-energy state of the chloroplast membrane is involved in the fluorescence lowering 
  Reference    (Z. Naturforsch. 31c, 722 [1976]; received August 10 1976) 
  Published    1976 
  Keywords    Chlorophyll Fluorescence, Chloroplasts, Fluorescence Quenching, Energized Membrane 
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 TEI-XML for    default:Reihe_C/31/ZNC-1976-31c-0722.pdf 
 Identifier    ZNC-1976-31c-0722 
 Volume    31 
20Author    Ian Fry, George Papageorgiou, Elisha Tel-Or, Lester PackerRequires cookie*
 Title    Reconstitution of a System for H 2 Evolution with Chloroplasts, Ferredoxin, and Hydrogenase  
 Abstract    Continuous light-dependent H2 production was studied in a reconstituted in vitro system using S pin acea oleracea chloroplasts, C lostridiu m pasteurianum hydrogenase and S piru lin a m axim a fer­ redoxin. Photosystem Il-dependent production at 30 °C is 60 —70 /^mol H2/mg chlorophyll. At 
  Reference    (Z. Naturforsch. 32c, 110 [1977]; received December 1 1976) 
  Published    1977 
  Keywords    Biophotolysis, H2 Production, Hydrogenase, Ferredoxin, Chloroplasts 
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 TEI-XML for    default:Reihe_C/32/ZNC-1977-32c-0110.pdf 
 Identifier    ZNC-1977-32c-0110 
 Volume    32