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1Author    Franz-C CzyganRequires cookie*
 Title    " Synthetical" Aiptasia mutabilis R A P P (Coelenterata)  
 Abstract    After being cultivated in the dark for some months and after being fed with food free of carotenoids during the time Aiptasia mutabilis (Coelenterata) loses its symbiontic algae (rich in brown fucoxanthin) and becomes transparent white. This disarranged symbiosis may be regenerated under light cultivation by adding different species of Chlorophyceae (Chlorella, Dunaliella) and Chrysophyceae (Ochromonas, Cyclotella), but not of Cyanophyceae (A nabaena, Nostoc, Oscillatoria, An a cystis). — This changeable life system be­ tween coelenterata and algae may be a good example for further studies of the endosymbiosis problem. 
  Reference    (Z. Naturforsch. 31c, 215 [1976]; eingegangen am 15. Dezember 1975) 
  Published    1976 
  Keywords    Aiptasia, Coelenterata, Symbiosis, Chlorella, Carotenoids 
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 TEI-XML for    default:Reihe_C/31/ZNC-1976-31c-0215_n.pdf 
 Identifier    ZNC-1976-31c-0215_n 
 Volume    31 
2Author    K.H G Rum BachRequires cookie*
 Title    Evidence for the Existence of Two ^-Carotene Pools and Two Biosynthetic ^-Carotene Pathways in the Chloroplast  
 Abstract    Two /7-Carotene pools were obtained in the chloroplast. It is concluded that one pool is very small like a-carotene and responsible exclusively for the biosynthesis of /?-ionone-xanthophylls. The other ^-carotene pool is proposed to be the one, that is located close to photosystem I and is involved in photosynthesis as a light protecting agent for chlorophylls against photo-oxidation. Furtherm ore evidence is given that both /7-carotene pools are synthesized by independent biosyn­ thetic pathways. 
  Reference    Z. Naturforsch. 34c, 1205 (1979); received Septem ber 4 1979 
  Published    1979 
  Keywords    Biosynthesis, Carotenoids, /?-Carotene, Photosynthesis 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-1205.pdf 
 Identifier    ZNC-1979-34c-1205 
 Volume    34 
3Author    Franz-C Czygan, Almuth KrügerRequires cookie*
 Title    Actinioerythrin in M ullus barbatus L  
 Abstract    Actinioerythrin has been isolated together with asta-xanthin-esters and /?-carotene from different samples of Mullus barbatus for the first time. 
  Reference    Z. Naturforsch. 37c, 340—341 (1982); eingegangen am 23. November 1981 
  Published    1982 
  Keywords    Mullus barbatus, Carotenoids, Actinioerythrin, Astaxanthin 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-0340_n.pdf 
 Identifier    ZNC-1982-37c-0340_n 
 Volume    37 
4Author    K. H. GrumbachRequires cookie*
 Title    Interconversion of Carotenoids and Quinones after Onset of Photosynthesis in Chloroplasts of Higher Plants  
 Abstract    The interconversion of carotenoids and quinones was investigated in beech and spinach leaves as well as isolated intact spinach chloroplasts following a dark-light transition. It is shown that isolated intact chloroplasts which are preincubated for 2 h at pH 7.6 in the dark and re­ illuminated with strong white light are capable not only o f deepoxidizing violaxanthin into antheraxanthin and zeaxanthin but simultaneously change the redox state o f the plastoquinone-pool in their thylakoid membrane. At the same time as violaxanthin is deepoxidized plasto-hydroquinone-9 is oxidized to plastoquinone-9. If the light is turned off zeaxanthin is epoxidized into antheraxanthin and violaxanthin but no significant change in the redox state o f the plasto-quinone-pool occurred. It is concluded that the deepoxidation of violaxanthin is connected to the photosynthetic electron transport in that way that an acidification o f the intrathylakoidal compartment by the vectorial release of protons from the water photooxidizing enzyme system and the plastoquinone-pool is required for the activation of the violaxanthin deepoxidase. This may be taken as further evidence that violaxanthin deepoxidase is located at the inner side o f the thylakoid membrane. Additional evidence for this location site is given by the observation that neither deepoxidation of violaxanthin nor photooxidation of plastohydroquinone-9 occurred after onset o f photosyn­ thesis if non cyclic electron transport was inhibited by DCMU. 
  Reference    Z. Naturforsch. 38c, 393 (1983); received March 15 1983 
  Published    1983 
  Keywords    Carotenoids, Photosynthesis, Quinones, Xanthophyll Cycle 
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 TEI-XML for    default:Reihe_C/38/ZNC-1983-38c-0393.pdf 
 Identifier    ZNC-1983-38c-0393 
 Volume    38 
5Author    G. E. Laskay, I. M. Lehoczki, L. Aróti, SzalayRequires cookie*
 Title    Effects of Pyridazinone Herbicides during Chloroplast Development in Detached Barley Leaves I. Effects on Pigment Accumulation and Fluorescence Properties  
 Abstract    The effects o f three differently substituted pyridazinone herbicides on the accum ulation o f photosynthetic pigments and on the fluorescence properties o f greening barley leaves were studied. The two trifluoro-methyl derivatives, SAN 6706 and 9789 caused inhibition in the accumulation o f carotenes only after the First 24 h o f greening. By the 48th hour o f greening no detectable amounts o f carotenes were present in the treated leaves. Considerable am ounts o f xanthophylls however remained present, and no bleaching o f the leaves was observed. It is suggested that SAN 6706 and 9789 prevent the formation o f the enzym e(s) catalyzing the desaturation o f phytoene and phytofluene. Fluorescence spectra indicate that the organization o f pigment forms altered seriously in the treated leaves. This experimental system may be useful to study the action o f pyridazinone herbicides without causing com plete photobleaching o f the photosynthetic apparatus. SAN 9785 had only minor effects on pigment accum ulation and also on the organization o f pigment forms. The possible explanations o f the effects observed are dis­ cussed. 
  Reference    Z. Naturforsch. 38c, 736—740 (1983); received June 8 1983 
  Published    1983 
  Keywords    Pyridazinone Herbicides, Carotenoids, Fluorescence Spectrum 
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 TEI-XML for    default:Reihe_C/38/ZNC-1983-38c-0736.pdf 
 Identifier    ZNC-1983-38c-0736 
 Volume    38 
6Author    A. Hloušek-Radojčič, N. LjubešičRequires cookie*
 Title    The Development of Daffodil Chromoplasts in the Presence of Herbicides SAN 9789 and SAN 9785  
 Abstract    The effects of two pyridazinone herbicides (SAN 9789 and SAN 9785) were studied on the fine structure and carotenoid composition during the transformation of chloroplasts into chromoplasts in daffodil (Narcissus poëticus L.) flowers. SAN 9789 caused the absence of big characteristic carotene crystals and the appearance of numerous nonosmiophilic plastoglobuli in chromoplasts. The accumulation of all carotenoids was drastically reduced and the content of carotenes was 40-fold lower than in the control. SAN 9785 caused no gross abnormalities in ultrastructure of chromoplasts. The synthesis of carotenes was partially reduced to about 75%. In spite of this the accumulation of xanthophylls is two times higher than in the control. The interaction between chromoplast ultrastructure and carotenoid composition is discussed. 
  Reference    Z. Naturforsch. 43c, 418—422 (1988); received December 7 1987/January 26 1988 
  Published    1988 
  Keywords    Pyridazinone Herbicides, Chromoplast Ultrastructures, Carotenoids 
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 TEI-XML for    default:Reihe_C/43/ZNC-1988-43c-0418.pdf 
 Identifier    ZNC-1988-43c-0418 
 Volume    43 
7Author    Andre Buche, Rafael PicorelRequires cookie*
 Title    Ectothiorhodospira sp  
 Abstract    Alkaline treatm ent of the Ectothiorhodospira sp. light harvesting system II induces mono-merisation of the bacteriochlorophylls and a bleaching of the carotenoid absorption bands in the visible region. Concomitantly, the maximum of absorption observed around 373 nm shifts towards 354 nm. This shift does not result from the Soret band but from a change of the absorption properties of the carotenoids. Furtherm ore, these pigments are not modified chemically but the spectral conversion results from environmental changes. It is assumed that the dissociation of the bacteriochlorophylls in alkaline medium is accompanied by a struc­ tural reorganisation of the complex which reinforces the interactions between the polypep­ tides and the carotenoids. 
  Reference    Z. Naturforsch. 55c, 576 (2000); : 3 4 -9 7 6 -5 7 5 6 2 0. received February 25/April 4 2000 
  Published    2000 
  Keywords    Carotenoid, Soret, Shift, Spirilloxanthin 
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 TEI-XML for    default:Reihe_C/55/ZNC-2000-55c-0576.pdf 
 Identifier    ZNC-2000-55c-0576 
 Volume    55 
8Author    Kai-Udo Sewe, Roland ReichRequires cookie*
 Title    The Effect of Molecular Polarization on the Electrochromism of Carotenoids * II. Lutein-Chlorophyll Complexes: The Origin of the Field-Indicating Absorption-Change at 520 nm in the Membranes of Photosynthesis  
 Abstract    Electrochromic spectra of monolayers of carotenoids (lutein and ß -carotene) in contact with monolayers of chlorophylls and of pheophytin a are measured in thin capacitors. A specific inter­ action of one of the OH-groups of lutein with the Mg-atom of chlorophyll is found. The formation of this oriented complex accounts for the fact that a part of the electrochromic absorption-change of lutein depends linearly on the electric field strength, whereas for lutein alone only a smaller, quadratic electrochromism is found. In the preparation with chlorophyll a, the maximum of this linear electrochromism is located at shorter wavelengths (512 nm) than in the preparation with chlorophyll b (517 nm). The permanent field that has been postulated in photosynthetic membranes (to explain the linear dependence of the field-indicating absorption-changes of the carotenoids) may also be at­ tributed to such a complex formation with chlorophylls. Especially, the field-indicating absorption-change at 520 nm can now be attributed mainly to a lutein-chlorophyll b complex. The absorption-change at 520 nm, calculated according to this model from the present experiments in vitro, is of the same order of magnitude as observed in vivo. Furthermore, this model agrees with the hitherto unexplained observation that in chlorophyll-b-lacking mutants the absorption-change at 520 nm is smaller than in normal plants, and the maximum is located at shorter wavelengths. Besites, it is concluded that lutein is mainly located in the regions of photosystem II. The contributions of the other carotenoids (especially of neoxanthin) to the spectrum of the field-indicating absorption-changes are also discussed. From the above model, some conclusions are drawn on the asymmetrical arrangement of the different pigments in the membrane of photosynthesis: The bulk chlorophyll molecules that serve as complex partners for the carotenoids should be located near to the inner surface of the thylakoid membrane, and the carotenoids attached to these chlorophylls should be located more to the out­ side. The phytol chain of a chlorophyll molecule should form an acute angle with the plane of the porphyrin ring. 
  Reference    (Z. Naturforsch. 32c, 161—171 [1977]; received January 20 1977) 
  Published    1977 
  Keywords    Electrochromism, Carotenoids, Molecular Complexes, Biological Membranes, Photosynthesis 
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 TEI-XML for    default:Reihe_C/32/ZNC-1977-32c-0161.pdf 
 Identifier    ZNC-1977-32c-0161 
 Volume    32 
9Author    H. K. Lichtenthaler, H. K. KleudgenRequires cookie*
 Title    Effect of the Herbicide San 6706 on Biosynthesis of Photosynthetic Pigments and Prenylquinones in Raphanus and in Hordeum Seedlings  
 Abstract    The pyridazinone herbicide San 6706 blocks chlorophyll and carotenoid formation simultaneously in a correlated way in both Raphanus and Hordeum seedlings. With decreasing carotenoid content the carotenoid precursor phytoene appears in San 6706-treated plants. The accumulation of the chloroplast prenylquinones (plastoquinone-9, a-tocopherol, <x-toco-quinone and vitamin Kj) is much less affected. This indicates that the biosynthesis of C20-and C45-prenyl chains (geranyl-geraniol, phytol and solanesol) which are incorporated in prenylquinones is not blocked by San 6706. It is assumed that the block of chlorophyll and carotenoid formation is due to one basic inhibi­ tion mechanism. The possibility that San 6706 may interfere with chloroplast ribosome formation, is discussed. 
  Reference    (Z. Naturforsch. 32c, 236 [1977]; received December 13 1976) 
  Published    1977 
  Keywords    Herbicide, Pyridazinone, Prenyl Biosynthesis, Carotenoids, Prenylquinones 
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 TEI-XML for    default:Reihe_C/32/ZNC-1977-32c-0236.pdf 
 Identifier    ZNC-1977-32c-0236 
 Volume    32 
10Author    Harald StranskyRequires cookie*
 Title    Die quantitative Bestimmung von Chloroplastenpigmenten im picomol-Bereich mit Hilfe einer isochratischen H PLC-M ethode A Method for the Quantitative Estimation of Chloroplast Pigments in the Picomole-Range by Use of a Isocratic HPLC-System  
 Abstract    A method is described for the estimation of the pigment content in chloroplasts by means of H P L C . The method is highly sensitive. Less than one picomole of individual pigments — equivalent to 1 m illigram m e fresh weight of spinach leaves — is needed for quantitative analysis. Analysis time is only 15 min, whereas in routine determination by thin layer chromatography a single sample needs 4 hours to be completed. Moreover the pigments are protected against desintegration by light and air. U sin g a isocratic H P LC -m eth od no equilibration of coloumns is necessary, thus permitting four runs per hour. 
  Reference    Z. Naturforsch. 33c, 836 (1978); eingegangen am 16. Oktober. 1978 
  Published    1978 
  Keywords    Carotenoids, Chloroplast Pigments, H igh Perform ance Liqu id Chromatography 
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 TEI-XML for    default:Reihe_C/33/ZNC-1978-33c-0836.pdf 
 Identifier    ZNC-1978-33c-0836 
 Volume    33 
11Author    N. Orbert, A. Dencher, Eilo HildebrandRequires cookie*
 Title    Sensory Transduction in Halobacterium halobium: Retinal Protein Pigment Controls UV-Induced Behavioral Response  
 Abstract    Both photosystems, PS 370 and PS 565, controlling behavioral responses in H alobacterium halo-bium [E. Hildebrand and N. Dencher, Nature 2 5 7 ,4 6 — 48 (1975)] are reversibly inhibited when bacteria are grown in the presence o f 1 mM nicotine which is known to block biosynthesis o f reti­ nal. Photobehavior can be restored within som e minutes to hours by adding retinal to nicotine-treated bacteria, PS 370 thereby reappearing earlier than PS 565. The reconstitution rate depends on the concentration and on the kind o f retinal isomers applied. A \\-trans retinal is m ost effective. PS 370 becomes fully sensitive if reconstituted in the presence o f nicotine. This rules out the possi­ bility that the alkaloid may directly inhibit steps o f signal transmission follow ing photoreception. The action spectrum o f PS 370 regenerated with retinal alone o f H. h., strain RjLg (a mutant deficient in carotenoids), fails to show all secondary peaks around 450 nm which in strain Rj occur besides the prominent maximum at 370 nm. A ddition o f carotenoids (m ainly a-bacterioruberin) to reconstituted cells o f R ,L3 restores the sensitivity in that spectral region. Carotenoids or flavin solely added to nicotine-treated bacteria cannot restore photobehavior. We conclude that the active pigm ent o f PS 370, which m ediates the photophobic response to increase o f light intensity (step-up response), represents a retinal protein com plex and that carote­ noids participate in photoreceptor function as accessory pigments. The biochem ical relation o f the UV-absorbing retinal protein com plex to bacteriorhodopsin is discussed. 
  Reference    Z. Naturforsch. 34c, 841 (1979); received June 5/July 6 1979 
  Published    1979 
  Keywords    Bacteria, Photophobic Response, Bacteriorhodopsin, Carotenoids, Accessory Pigment 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-0841.pdf 
 Identifier    ZNC-1979-34c-0841 
 Volume    34 
12Author    Marc Symons, Anthony CroftsRequires cookie*
 Title    Flash-Induced Electrochromic Band Shifts, is It a Simple Mechanism?  
 Abstract    The flash-induced carotenoid bandshifts have been studied for various strains of both Rho-dopseudomonas sphaeroides and capsulata. A technique for calculating shifts o f isobestic points down to 0.05 nm is described. To this end, special attention has been paid to the appropriate cor­ rection for reaction center absorbance changes occuring concommitantly with the carotenoid bandshifts. Plots of the wavelength o f the isobestic point versus the corresponding absorption changes at the maximum o f the difference spectrum have been made, suggesting the existence o f different pools of carotenoids. The various pools of carotenoids seem to have different sizes, in­ ducing non-linearities in the plots. In some cases spectral differences of the pools have to be assumed. A possible interpretation o f the results would be that each electrogenic span of the electron transport chain is to be associated with its own pool of carotenoids, all the pools behaving in somewhat independant way. We discuss possible difficulties in making those measurements. 
  Reference    Z. Naturforsch. 35c, 139—144 (1980); received August 16 1979 
  Published    1980 
  Keywords    Electrochromism, Carotenoids, Electron Transport, Membrane Potential, Photosynthesis 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0139.pdf 
 Identifier    ZNC-1980-35c-0139 
 Volume    35 
13Author    LudwigJ M Becker, Hans-Ulrich MeischRequires cookie*
 Title    Effect of Vanadate and Iron Stress on the Pigment Composition of Chlorella fusca  
 Abstract    The pigment composition o f Chlorella fusca has been investigated in the absence and in presence of vanadate and during iron stress. 1. Fe-deficiency generally decreases algal pigment content without change of the ratio chloro­ phyll a/b. 2. A twofold vanadate induced increase o f the chlorophylls is accompanied by a similar enhancement o f several xanthophylls, while lutein remains unaffected. 3. Vanadate stimulates the formation o f ^-carotene up to 5 fold, the effect being less obvious during iron stress. 
  Reference    Z. Naturforsch. 36c, 207 (1981); received November 171980 
  Published    1981 
  Keywords    Carotenoids, Chlorella fusca, Chlorophylls, Iron Stress, Vanadate 
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 TEI-XML for    default:Reihe_C/36/ZNC-1981-36c-0207.pdf 
 Identifier    ZNC-1981-36c-0207 
 Volume    36 
14Author    Hartm Ut KayserRequires cookie*
 Title    Carotenoid Biogenesis in the Stick Insect, Carausius morosus, during a Larval Instar  
 Abstract    [14C]/?-Carotene was fed to juvenile stick insects, Carausius morosus, o f the fifth instar. Radio­ activity was incorporated into 2-hydroxy-, 2-oxo-, and 3,4-didehydro-2-oxo-carotenoids o f the ß,ß-type. These transformations are due to the insect's own capacity; any contribution by microbial symbionts can be ruled out. A study on the labelling kinetics clearly shows that the biogenesis of hydroxy-and oxo-carotenoids is correlated to a decrease in the carotene precursor, but only up to mid instar. Thereafter, oxidation o f the carotene is very low but the transformations of its metabolites continue as before. Predominantly ß,^-carotene-2,2'-diol is dehydrogenated to 3,4,3',4'-tetradehydro-/?,/?-carotene-2,2'-dione via two hydroxyketones. This discontinuous utilization o f /7-carotene could be due to a stop at mid instar either in the oxidation or in the absorption in the gut o f this precursor. 
  Reference    Z. Naturforsch. 37c, 13 (1982); received September 11/October 281981 
  Published    1982 
  Keywords    Carotenoids, Metabolism, [14C]/?-Carotene, Insects, Carausius morosus 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-0013.pdf 
 Identifier    ZNC-1982-37c-0013 
 Volume    37 
15Author    K.H G RuRequires cookie*
 Title    Herbicides which Inhibit Electron Transport or Produce Chlorosis and Their Effect on Chloroplast Development in Radish Seedlings. III. Plastid Pigment and Quinone Composition  
 Abstract    The effect o f DC M U , bentazon, amitrole and SA N 6706 on the form ation o f chloroplast pig­ ments and quinones was investigated using plants that were grown in total darkness or continuous white, red or far-red light. All herbicides assayed affected the formation o f chlorophylls, carotenoids and quinones but DC M U had only minor effects. Like for chlorophylls and carotenoids the form ation o f quinones was most suppressed in plants grown in the presence o f the herbicide in continuous white or red light, but the effect on the formation o f quinones was much lower as com pared to the pigments. The observation that the biosynthesis o f quinones is still m aintained in SA N 6706 treated bleach­ ed plastids which are lacking chlorophylls and carotenoids indicates that quinones are synthesized at the plastitd envelope and stored in the osm iophilic plastoglobuli. Amitrole and SA N 6706 induced a strong chlorosis. It was o f particular interest that chlorosis was also induced by the photosystem II inhibitor bentazon. D C M U was not effective. The inhibi­ tor concentration for 50% inhibition in the chlorophyll and carotenoid content was 5 x l 0 ~6 M for SAN 6706,3 x 10-4 M for am itrole and 10~3 M for bentazon. As already reported by others SA N 6706 treated plants accum ulated phytoene in large amounts. The highest phytoene content was observed in plants that were grown in the dark. A m itrole treat­ ed plants accumulated lycopene. But in addition other carotenoid precursors like phytoene and phjHofluene were also accum ulated. In contrast to phytoene lycopene was only accum ulated in plants that were grown in the light. Particularly for SA N 6706 and amitrole the expression o f the bleaching effect was depending on the light intensity and light quality that was used during plant growth. T he herbicide effect ewas predominantly expressed at higher light intensities and after irradiation with red light. The o b ­ servation that the induction o f chlorosis is very sensitive to red light as com pared to w hite or blue light is suggesting that phytochrom e is involved in the developm ent o f the herbicide toxicity. It also supports that in SA N treated plants chlorophylls are photodecom posed directly by light be­ cause o f the lack o f photoprotecting carotenoids but m ainly /?-carotene in these plastids. Further support for this was given by the demonstration that SA N treated plants w hich were grown at very low light intensities turned green and were photosynthetically active. 
  Reference    Z. Naturforsch. 37c, 642 (1982); received April 5 1982 
  Published    1982 
  Keywords    Bleaching Herbicides, Carotenoids, Chlorophylls, Lycopene, Photosystem II H erbicides 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-0642.pdf 
 Identifier    ZNC-1982-37c-0642 
 Volume    37 
16Author    Jürgen Feierabend, TheresiaW. Inkelhüsener, Petra Kemmerich, Ulrike SchulzRequires cookie*
 Title    Mechanism of Bleaching in Leaves Treated with Chlorosis-Inducing Herbicides  
 Abstract    Bleaching o f chlorophyll was studied in the leaves of rye seedlings (Secale cereale L.) treated with four chlorosis-inducing herbicides of different potency (weak photodestructions, group 1: aminotriazole, haloxidine; strong photodestructions, group 2: San 6706, difunone). Chlorophyll deficiency and particularly the inactivation of a chloroplast marker enzyme, NADP-dependent glyceraldehyde-3-P dehydrogenase, that occurred in the presence o f group 2 herbicides were stronger in red, than in blue, light. When grown in white light o f low intensity (10 lx) herbicide-treated leaves contained chloro­ phyll, 70 S ribosomes and unimpaired activities o f NADP-dependent glyceraldehyde-3-P de­ hydrogenase. At 10 lx only the leaves treated with SAN 6706 and difunone were strongly carotenoid-deficient but not those treated with group 1 herbicides. After all herbicide treatments 10 lx-grown leaf tissue was, however, not capable o f photosynthetic 0 2-evolution indicating some disorder of photosynthetic electron transport. Leaf segments grown at 10 lx were exposed to a high light intensity o f 30000 lx at either 0 ° C or 30 °C. In treatments with group 1 herbicides chlorophyll accumulation was stopped in bright light at 30 °C but breakdown was not apparent. Only at 0 °C and in the presence of high, growth-reducing, herbicide concentrations chlorophyll was slightly degraded. The RNAs o f the 70S ribosomes were, however, clearly destroyed at 30000 lx and 30 °C in aminotriazole-treated leaves. In leaves treated with group 2 herbicides chlorophyll was rapidly degraded at 30000 lx both at 0 ° C and 30 °C, however, only in the presence of 0 2, indicating a true photooxidative and mainly photochemical nature o f the reactions involved. This chlorophyll breakdown was accompanied by the photodestruction of 70S ribosomes and the inactivation of NADP-glyceraldehyde-3-P dehydrogenase. In treatments with group 1 herbicides photoinactivation o f the latter enzyme did not occur, although it was clearly localized in the bleached plastids, as demonstrated by gradient separation o f organelles. In the presence of group 2 herbicides the chlorosis was originating from a direct photo­ oxidation of chlorophyll, accompanied by a massive destruction o f other plastid constituents and functions. In treatments with group 1 herbicides photodestructions appeared to be much weaker and insufficient to affect chlorophyll directly. Mediated through some photodestructive inter­ ference with obviously more sensitive plastid components, such as their ribosomes, further chlorophyll accumulation was, however, prevented. 
  Reference    Z. Naturforsch. 37c, 898 (1982); received July 7 1982 
  Published    1982 
  Keywords    Bleaching Herbicides, Carotenoids, Chlorophyll, Photooxidation, Plastid rRNA 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-0898.pdf 
 Identifier    ZNC-1982-37c-0898 
 Volume    37 
17Author    K.H G Rum BachRequires cookie*
 Title    Distribution of Chlorophylls, Carotenoids and Quinones in Chloroplasts of Higher Plants  
 Abstract    Leaves, cotyledons, isolated chloroplasts and subplastid fractions (thylakoids and envelopes) o f radish (Raphanus sativus L. cv. Saxa) and spinach (Spinacia oleracea L. cv. M atador) were assayed for their pigment and quinone content and com position. Virtually all the chlorophylls, carotenoids and quinones were contained in the thylakoids. Envelopes prepared by the method described contained very low amounts o f chlorophyll a and b, violaxanthin and neoxanthin, but no /7-carotene, lutein, zeaxanthin and antheraxanthin. Am ong the quinones trace am ounts o f plastoquinone and a-tocopherol but no plastohydroquinone, a-tocoquinone and phylloquinone were detected. Presented data may be taken as evidence that in vivo the chloroplast envelope is not a location site o f carotenoids and quinones as generally accepted. Possible im plications for the biosyntheses o f quinones and pigments are discussed. 
  Reference    Z. Naturforsch. 38c, 996—1002 (1983); received August 16 1983 
  Published    1983 
  Keywords    Carotenoids, Chlorophylls, Chloroplasts, Envelopes, Quinones, Thylakoids 
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 TEI-XML for    default:Reihe_C/38/ZNC-1983-38c-0996.pdf 
 Identifier    ZNC-1983-38c-0996 
 Volume    38 
18Author    ArminR. Gemmrich, Hartmut KayserRequires cookie*
 Title    Hormone Induced Changes in Carotenoid Composition in Ricinus Cell Cultures. II. Accumulation of Rhodoxanthin during Auxin-Controlled Chromoplast Differentiation  
 Abstract    The effects of auxin and cytokinin on light dependent carotenoid synthesis were studied in callus cultures derived from Ricinus endosperm tissue. Chloroplasts differentiate when calli are grown in the light in the presence of cytokinin and auxin. When cultures are transferred to an auxin-free medium, chromoplast differentiation is initiated, i.e. rhodoxanthin accumulates whereas lutein and chlorophyll content decrease and the plastid morphology changes from that of a typical chloroplast to that of a globular-type chromoplast. These changes are fully reverted by readdition of auxin. Plastid differentiation into either chloroplasts or chromoplasts in Ricinus endosperm cultures therefore appears to be controlled by auxin and cytokinin. 
  Reference    Z. Naturforsch. 39c, 753—757 (1984); received May 11 1984 
  Published    1984 
  Keywords    Plant Cell Cultures, Cytokinin, Auxin, Plastid Differentiation, Carotenoids 
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 TEI-XML for    default:Reihe_C/39/ZNC-1984-39c-0753.pdf 
 Identifier    ZNC-1984-39c-0753 
 Volume    39 
19Author    SeymourSteven BrodyRequires cookie*
 Title    Flash Photolysis of Liposomes Containing Chlorophyll and Zeaxanthin, as a Function of Temperature (2 °—34 °C)  
 Abstract    The transfer o f triplet excitation from chlorophyll to zeaxanthin in lip osom es is a function o f temperature and pigment concentration. At 525 nm both chlorophyll and zeaxanthin triplet states are observed. The result is a biphasic increase in absorption. The rise time o f absorption by the chlorophyll triplet is much faster, than by the zeaxanthin triplet. With increasing temperature the contribution o f absorption by zea­ xanthin (relative to that o f chlorophyll) at 525 nm increases, and its rise tim e gets faster. At high ratios o f zeaxanthin to chlorophyll, temperature has less effect on both the rise tim e and absorption by the zeaxanthin triplet state. The chlorophyll triplet is measured at 780 nm. It decays faster with increasing temperature and or increasing ratio o f zeaxanthin to chlorophyll. The results are interpreted in terms of: increasing fluidity o f the lipid lip osom e with tem per­ ature, formation o f zeaxanthin-chlorophyll com plexes at high ratios o f zeaxanthin and chloro­ phyll, presence o f different lipid phases in the lip osom e bilayer. 
  Reference    Z. Naturforsch. 39c, 1108—1111 (1984); received June 15 1984 
  Published    1984 
  Keywords    Chlorophyll, Carotenoid, Liposomes, Triplet States, Excitation Energy Transfer 
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 TEI-XML for    default:Reihe_C/39/ZNC-1984-39c-1108.pdf 
 Identifier    ZNC-1984-39c-1108 
 Volume    39 
20Author    Sibille Schindler, J. Thomas, H. Bach, K. Artm, LichtenthalerRequires cookie*
 Title    Differential Inhibition by Mevinolin of Prenyllipid Accumulation in Radish Seedlings  
 Abstract    We have studied in intact radish seedlings the effects o f m evinolin (at concentrations o f 0.25 to 5 [am), a specific inhibitor o f HM G -CoA reductase, and. therefore, o f m evalonate biosynthesis, on the production o f various isopentenoids and prenyllipids. Whereas the content o f free desmethyl sterols was decreased steadily, only depending on the concentration o f inhibitor present in the parts o f seedlings investigated separately (e.g. roots, hypocotyls, and cotyledons), the effect on ubiquinone accumulation^ was different. Irrespective o f the part o f seedlings being analyzed, the maximal inhibition reached was 50%. Plastidic pigm ent accum ulation, however, as well as that o f chloroplast quinones (plastoquinone and phylloquinone), appeared even to be enhanced at low inhibitor concentrations and was not significantly lowered by application o f 5 ^m mevinolin. a-Tocopherol showed a similar profile in the dose response to com pounds known to be exclusively synthesized in the plastid. The results indicate a differential accessibility o f the m evalonate synthesizing enzymes presumably present in the cytoplasm, m itochondria and plastids in respect to the inhibitory action o f mevinolin. If prenyllipid formation in the different cell compartments solely depended on cytoplasm ic m evalonate biosynthesis, all prenyllipids should be affected to the same extent as the sterols, which are exclusively synthesized by cytoplasm ic enzymes. 
  Reference    Z. Naturforsch. 40c, 208 (1985); received D ecem ber 5 1984 
  Published    1985 
  Keywords    Carotenoids, Chlorophylls M evinolin Plastoquinone-9, Sterol Accumulation 
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 TEI-XML for    default:Reihe_C/40/ZNC-1985-40c-0208.pdf 
 Identifier    ZNC-1985-40c-0208 
 Volume    40