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3082. The deep red state of photosystem II in Cyanidioschyzon merolae
- Creator:
- Langley, J., Morton, J., Purchase, Rupert, Tian, L., Shen, L., Han, G., Shen, J.-R., and Krausz, E.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- optická spektroskopie, fotosyntéza, optical spectroscopy, photosynthesis, optical spectra, 2, and 581
- Language:
- Multiple languages
- Description:
- We identified and characterised the deep red state (DRS), an optically-absorbing charge transfer state of PSII, which lies at lower energy than P680, in the red algae Cyanidioschyzon merolae by means of low temperature absorption and magnetic circular dichroism spectroscopies. The photoactive DRS has been previously studied in PSII of the higher plant Spinacia oleracea, and in the cyanobacterium Thermosynechococcus vulcanus. We found the DRS in PSII of C. merolae has similar spectral properties. Treatment of PSII with dithionite leads to reduction of cytochrome (cyt) b559 and the PsbV-based cyt c550 as well as the disassembly of the oxygen-evolving complex. Whereas the overall visible absorption spectrum of PSII was little affected, the DRS absorption in the reduced sample was no longer seen. This bleaching of the DRS is discussed in terms of a corresponding lack of a DRS feature in D1D2/cyt b559 reaction centre preparations of PSII., J. Langley, J. Morton, R. Purchase, L. Tian, L. Shen, G. Han, J.-R. Shen, E. Krausz., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3083. The development of chloroplast structure during leaf ontogeny
- Creator:
- Kutík, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- environmental effects, leaf life span, and stresses
- Language:
- Multiple languages
- Description:
- Advances achieved during last fifteen years in the understanding the development of chloroplast ultrastructure during natural leaf ontogeny are summarized. Life span of a typical C3 mesophyll cell chloroplast is outlined and placed into the scheme of cyclic plastid interrelationships. Possible modifications of this development by stresses, environmental factors or experimental treatments are also shown.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3084. The development of chloroplast ultrastructure and Hill reaction activity during leaf ontogeny in different maize (Zea mays L.) genotypes
- Creator:
- Kutík, J., Kočová, M., Holá, D., and Körnerová, M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chloroplast dimensions, electron microscopy, peripheral reticulum, photosynthesis, plastoglobuli, starch, stereology, stroma, and thylakoids
- Language:
- Multiple languages
- Description:
- Changes in Hill reaction activity (HRA) and ultrastructure of mesophyll cell (MC) chloroplasts were studied during the ontogeny of third leaf of maize plants using polarographic oxygen evolution measurement, transmission electron microscopy, and stereology. The chloroplast ultrastructure was compared in young (actively growing), mature, and senescing leaves of two different inbreds and their reciprocal F1 hybrids. Statistically significant differences in both HRA and MC chloroplast ultrastructure were observed between different stages of leaf ontogeny. Growth of plastoglobuli was the most striking characteristic of chloroplast maturation and senescence. The chloroplasts in mature and senescing leaves had a more developed system of thylakoids compared to the young leaves. Higher HRA was usually connected with higher thylakoid volume density of MC chloroplasts. and J. Kutík ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3085. The differential effect of photoinhibition on the quantum yield of oxygen evolution and on the electron transport capacity studied with isolated spinach thylakoids
- Creator:
- Richter, M., Bóthin, B., and Wild, A.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- The light response changes of oxygen evolutíon in the isolated spinách (Spinacia oleracea L.) thylakoids associated with the photoinhibition, influenced by the temperature and radical protection, were determined. Photoinhibition was performed at 20 ®C with or without an addition of antioxidant mixture consisting of glutathione, ascorbate, superoxide dismutase and catalase, oř, altematívely, at 0 oC without the antioxidants. Beside the effects on decline of atrazine binding sites and variable room temperature fluorescence, the three variants of photoinhibition differed with respect to their effects on the yield of oxygen evolutíon. Quantum yield of oxygen evolutíon (<{>02) flecline preceded Úie decrease of electron transport capacity at the beginning, while similar low values were found at the end of the treatment. In the presence of antioxidants the electron transport capacity remained high, whereas marked decline of (|»o^ occurred with the equally treated thylakoids. Comparable deviating behaviour of (t»Oj and the electron transport capacity was not found following photoinhibition at 0 oC; both were affected to the same degree, regardless if ferricyanide or the Qg- independent electron acceptor siUcomolybdate were ušed. With isolated thylakoids the quotient FyF,„, which is often ušed as a measure for photochemical efficiency of open photosystem 2 reaction centres in whole plant studies, did not decline to the same extent as (|)Oj under the dififerent photoinhibitoiy conditions applied. The main conclusion is that in thylakoid photoinhibition the independent mechanisms are associated with the changes of both the and electron transport capacity, and that the (j>02-related mechanism is inhibited at 0 oC.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3086. The distinctive pattern of photosystem 2 activity, photosynthetic pigment accumulation, and ribulose-1,5-bisphosphate carboxylase/oxygenase content of chloroplasts along the axis of primary wheat leaf lamina
- Creator:
- Dilnawaz, F., Mohapatra, P., Misra, M., Ramaswamy, N. K., and Misra, A. N.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- carotenoids, chlorophyll, CO2 fication ability, photosystem 2, protein, thylakoid, and Triticum aestivum
- Language:
- Multiple languages
- Description:
- Wheat (Triticum aestivum L. cv. Sonalika) seedlings were grown in Hoagland solution. Primary leaves were harvested at 8, 12, and 15 d and cut into five equal segments. Contents of photosynthetic pigments and proteins, and photosystem 2 (PS2) activity increased from base to apex of these leaves. Chlorophyll (Chl) content was maximum at 12 d in all the leaf segments, but PS2 activity showed a gradual decline from 8 to 15 d in all leaf segments. In sharp contrast, the CO2 fixation ability of chloroplasts increased from 8 to 15 d. CO2 fixation ability of chloroplasts started to decline from base to apex of 15-d-old seedlings, where the content of ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (RuBPCO-LSU) increased acropetally. RuBPCO-LSU content was maximum in all the leaf segments in 12-d-old seedlings. This shows a distinctive pattern of PS2, Chl, CO2 fixation ability of chloroplasts, and RuBPCO-LSU content along the axis of leaf lamina during development and senescence. RuBPCO-LSU (54 kDa) degraded to fragments of 45, 42, 37, 19, and 16 kDa products which accumulated along the leaf axis during ageing of chloroplasts. Thus the CO2 fixation ability of chloroplasts declines earlier than PS2 activity and photosynthetic pigment contents along the leaf lamina. and F. Dilnawaz ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3087. The early history of "Photosynthetica", "Photosynthesis Research", and their publishers
- Creator:
- Govindjee, Šesták, Z., and Peters, W. R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Kluwer Academic Publishers, Martinus Nijhoff, Photosynthesis Research, Photosynthetica, and René Marcelle
- Language:
- Multiple languages
- Description:
- The history of the journals "Photosynthetica" and "Photosynthesis Research" is traced from its beginning. Their development is related to the history of several publishers (Dr W. Junk Publishers, Martinus Nijhoff, Kluwer Academic Publishers). This account is based on recollections and records of the authors, Ad C. Plaizier, and René Marcelle (the first Editor-in-Chief of Photosynthesis Research). and Govindjee, Z. Šesták, W. R. Peters.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3088. The effect of abscisic acid and methyl jasmonate on carbonic anhydrase activity in pea
- Creator:
- Lazova, G. N., Kicheva, M. I., and Popova, L. P.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- intercellular CO2 concentration, net photosynthetic rate, plant hormones, stomatal conductance, and Pisum sativum
- Language:
- Multiple languages
- Description:
- Short-term (2 h) treatment with 10 µM abscisic acid decreased stomatal conductance and net photosynthetic rate, and increased carbonic anhydrase activity in pea seedlings. The treatment with 10 µM methyl jasmonate did not significantly affect these parameters. and G. N. Lazova, M. I. Kicheva, L. P. Popova.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3089. The effect of additional red irradiation on the photosynthetic apparatus of Pisum sativum
- Creator:
- Topchiy, N. M., Sytnik, S. K., Syvash, O. O., and Zolotareva, O. K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll, light-emitting diodes, light-harvesting complex, non-photochemical quenching, photosystem 2, Pisum sativum, photochemical quenching, and spectral composition of radiation
- Language:
- Multiple languages
- Description:
- Pisum sativum (L.) plants were grown under "white" luminescent lamps, W [45 µ mol(quantum) m-2 s-1] or under the same irradiation supplemented with narrow spectrum red light-emitting diodes (LEDs), RE [λmax = 660 nm, Δλ = 20 nm, 40 µmol(quantum) m-2 s-1]. Significant differences in the chlorophyll (Chl) a fluorescence parameters, degree of State 1-State 2 transition, and the pigment-protein contents were found in plants grown under differing spectral composition. Addition of red LEDs to the "white light" resulted in higher effective quantum yield of photosystem 2 (PS2), i.e. F'v/F'm, linear electron transport (ϕPS2), photochemical quenching (qP), and lower non-photochemical quenching (qN as well as NPQ). The RE plants were characterised by higher degree State 1-State 2 transition, i.e. they were more effective in radiant energy utilisation. Judging from the data of "green" electrophoresis of Chl containing pigment-protein complexes of plants grown under various irradiation qualities, the percentage of Chl in photosystem 2 (PS2) reaction centre complexes in RE plants was higher and there was no difference in the total Chl bound with Chl-proteins of light-harvesting complexes (LHC2). Because the ratio between oligomeric and monomeric LHC2 forms was higher in RE plants, we suggest higher LHC2 stability in these ones. and N. M. Topchyi ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3090. The effect of altered sink-source relations on photosynthetic traits and matter transport during the phase of reproductive growth in the annual herb Chenopodium album
- Creator:
- Yasumura, Y.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- leaf senescence, nitrogen resorption, photosynthetic nitrogen use efficiency, and soluble protein
- Language:
- Multiple languages
- Description:
- Annual plants transport a large portion of carbohydrates and nitrogenous compounds from leaves to seeds during the phase of reproductive growth. This study aimed to clarify how reproductive growth affects photosynthetic traits in leaves and matter transport within the plant in the annual herb Chenopodium album L. Plants were grown in pots and either reproductive tissues or axillary leaves were removed at anthesis. Matter transport was evaluated as temporal changes in dry mass (as a substitute of carbohydrates) and nitrogen content of aboveground organs: leaves, axillary leaves, stems and reproductive tissues. Photosynthetic capacity (light-saturated photosynthetic rate under ambient CO2 concentration), nitrogen, chlorophyll and soluble protein content were followed in the 20th leaf that was mature at the start of the experiment. Removal of reproductive tissues resulted in accumulation of dry mass in leaves and axillary leaves, and accumulation of nitrogen in stem as nitrogen resorption from leaves and axillary leaves proceeded with time. Removal of axillary leaves proportionally reduced dry mass and nitrogen allocation to reproductive tissues, thus affecting the quantity but not quality of seeds. Removal treatments did not alter the time course of photosynthetic capacity, nitrogen, chlorophyll or soluble protein content during senescence in the 20th leaf, but changed the photosynthetic capacity per unit of leaf nitrogen according to demand from reproductive tissues. Together, the results indicate that reproductive tissues affected carbon and nitrogen economy separately. The amount of carbon was adjusted in leaves through photosynthetic capacity and carbohydrate export from them, and the amount of nitrogen was adjusted by transport from stem to reproductive tissues. The plant's ability to independently regulate carbon and nitrogen economy should be important in natural habitats where the plant carbon-nitrogen balance can easily be disturbed by external factors.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public