Abstract:
:When 23°C-grown potato leaves (Solanum tuberosum L.) were exposed for 15 min to elevated temperatures in weak light, a dramatic and preferential inactivation of Photosystem (PS) II was observed at temperatures higher than about 38°C. In vivo photoacoustic measurements indicated that, concomitantly with the loss of PS II activity, heat stress induced a marked gas-uptake activity both in far-red light (>715 nm) exciting only PS I and in broadband light (350-600 nm) exciting PS I and PS II. In view of its suppression by nitrogen gas and oxygen and its stimulation by high carbon-dioxide concentrations, the bulk of the photoacoustically measured gas uptake by heat-stressed leaves was ascribed to rapid carbon-dioxide solubilization in response to light-modulated stroma alkalization coupled to PS I-driven electron transport. Heat-induced gas uptake was observed to be insensitive to the PS II inhibitor diuron, sensitive to the plastocyanin inhibitor HgCl2 and saturated at a rather high photon flux density of around 1200 μE m(-2) s(-1). Upon transition from far-red light to darkness, the oxidized reaction center P700(+) of PS I was re-reduced very slowly in control leaves (with a half time t1/2 higher than 500 ms), as measured by leaf absorbance changes at around 820 nm. Heat stress caused a spectacular acceleration of the postillumination P700(+) reduction, with t1/2 falling to a value lower than 50 ms (after leaf exposure to 48°C). The decreased t1/2 was sensitive to HgCl2 and insensitive to diuron, methyl viologen (an electron acceptor of PS I competing with the endogenous acceptor ferredoxin) and anaerobiosis. This acceleration of the P700(+) reduction was very rapidly induced by heat treatment (within less than 5 min) and persisted even after prolonged irradiation of the leaves with far-red light. After heat stress, the plastoquinone pool exhibited reduction in darkness as indicated by the increase in the apparent Fo level of chlorophyll fluorescence which could be quenched by far-red light. Application (for 1 min) of far-red light to heat-pretreated leaves also induced a reversible quenching of the maximal fluorescence level Fm, suggesting formation of a pH gradient in far-red light. Taken together, the presented data indicate that PS I responded to the heat-induced loss of PS II photochemical activity by catalyzing an electron flow from stromal reductants. Heat-stress-induced PS I electron transport independent of PS II seems to constitute a protective mechanism since block of this electron pathway in anaerobiosis was observed to result in a dramatic photoinactivation of PS I.
journal_name
Photosynth Resjournal_title
Photosynthesis researchauthors
Havaux Mdoi
10.1007/BF00017756subject
Has Abstractpub_date
1996-01-01 00:00:00pages
85-97issue
1eissn
0166-8595issn
1573-5079journal_volume
47pub_type
杂志文章abstract::The effect of desiccation and rehydration on the function of Photosystem II has been studied in the desiccation tolerant lichen Cladonia convoluta by thermoluminescence. We have shown that in functional fully hydrated thalli thermoluminescence signals can be observed from the recombination of the S2(3)QB (-) (B band),...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00041010
更新日期:1996-05-01 00:00:00
abstract::Significance of molecular crowding in grana thylakoids of higher plants on photosystem II function was studied by 'titrating' the naturally high protein density by fusing unilamellar liposomes of the native lipid mixture with isolated grana membranes (BBY). The incorporation of lipids was monitored by equilibrium dens...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-007-9253-2
更新日期:2008-02-01 00:00:00
abstract::Chlorophyll f is a photosynthetic pigment that was discovered in 2010. In this study, we present investigations on spectral and dynamic characteristics of singlet-excited and triplet states of Chl f with the application of ultrafast time-resolved absorption and fluorescence spectroscopies. The pigment was studied at r...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-014-9981-z
更新日期:2014-07-01 00:00:00
abstract::A combination of inhibitor and (15)N studies were used to investigate the photorespiratory nitrogen cycle in maize, a C4 plant. Inhibitors used included isonicotinyl hydrazide which blocks the conversion of glycine to serine, methionine sulfoximine an inhibitor of GS and azaserine an inhibitor of GOGAT. Results from l...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00041796
更新日期:1983-01-01 00:00:00
abstract::The world is facing energy crisis and environmental issues due to the depletion of fossil fuels and increasing CO2 concentration in the atmosphere. Growing microalgae can contribute to practical solutions for these global problems because they can harvest solar energy and capture CO2 by converting it into biofuel usin...
journal_title:Photosynthesis research
pub_type: 杂志文章,评审
doi:10.1007/s11120-013-9828-z
更新日期:2013-11-01 00:00:00
abstract::Recent magnetic-resonance work on YŻ suggests that this species exhibits considerable motional flexibility in its functional site and that its phenol oxygen is not involved in a well-ordered hydrogen-bond interaction (Tang et al., submitted; Tommos et al., in press). Both of these observations are inconsistent with a ...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00020428
更新日期:1995-11-01 00:00:00
abstract::The nature of interaction of cytochrome b-559 high potential (HP) with electron transport on the reducing side of photosystem II was investigated by measuring the susceptibility of cytochrome b-559HP to 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) under different conditions. Submicromolar DCMU concentrations decreas...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00035839
更新日期:1991-03-01 00:00:00
abstract::When excited by ultraviolet radiation, leaves of a great number of species of higher plants exhibit emission of blue fluorescence, comparable in intensity to the red emission of chlorophyll. The fluorescence decay of the blue emission of spinach leaves recorded by single photon counting techniques is decomposed into e...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00033171
更新日期:1990-09-01 00:00:00
abstract::The engagement of different photoprotective mechanisms in the cells of the carotenogenic astaxanthin-accumulating chlorophyte Haematococcus pluvialis (i) under favorable conditions, (ii) in the course of stress-induced haematocyst formation and (iii) during recovery from the stress was studied. To this end, we followe...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-016-0246-x
更新日期:2016-06-01 00:00:00
abstract::Two green algal species, Chlamydomonas reinhardtii and Scenedesmus obliquus, exhibited a relative maximum during the decay of luminescence, when adapted to low CO2 conditions that was not observed in high CO2 adapted cells.From the kinetics of transient changes in the level of dark fluorescence, after illumination and...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00034857
更新日期:1990-03-01 00:00:00
abstract::Energy storage measurements by modulated photothermal radiometry (PTR) were carried out on intact leaves to assess the value of the PTR method for photosynthesis research. In particular, correlations to the redox state of P700 under various conditions were examined. PTR monitors modulated light conversion to heat by s...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00035379
更新日期:1991-08-01 00:00:00
abstract::To determine the fluorescence properties of cyanobacterial Photosystem I (PS I) in relatively intact systems, fluorescence emission from 20 to 295 K and polarization at 77 K have been measured from phycobilisomes-less thylakoids of Synechocystis sp. PCC 6803 and a mutant strain lacking Photosystem II (PS II). At 295 K...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00028785
更新日期:1992-02-01 00:00:00
abstract::Phycobilisomes (PBS) are antenna complexes that harvest light for photosystem (PS) I and PS II in cyanobacteria and some algae. A process known as far-red light photoacclimation (FaRLiP) occurs when some cyanobacteria are grown in far-red light (FRL). They synthesize chlorophylls d and f and remodel PS I, PS II, and P...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-016-0303-5
更新日期:2017-02-01 00:00:00
abstract::The content and composition of pigments and acyl lipids (monogalactosyl diacylglycerol, digalactosyl diacylglycerol and phosphatidyl glycerol) have been investigated in developing chloroplasts isolated from successive 2-cm sections along the leaves of wheat seedlings grown either under 100, 30 or 3 W·m(-2). In all exa...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00035244
更新日期:1986-01-01 00:00:00
abstract::We evaluate low-temperature (low-T) emission spectra of photosystem II core complexes (PSII-cc) previously reported in the literature, which are compared with emission spectra of PSII-cc obtained in this work from spinach and for dissolved PSII crystals from Thermosynechococcus (T.) elongatus. This new spectral datase...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-015-0128-7
更新日期:2015-06-01 00:00:00
abstract::Chloroplast NADP-dependent malate dehydrogenase (NADP-MDH, EC 1.1.1.82) is inactive in the dark and activated in the light via a reduction of specific disulfides by thiol-disulfide interchange with thioredoxin, reduced by the photosynthetic electron transfer. Compared to the constitutively active NAD-dependent forms, ...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1023/A:1016099228450
更新日期:2002-01-01 00:00:00
abstract::The current study confirmed earlier conclusions regarding differential ozone (O(3)) tolerances of two soybean cultivars, Essex and Forrest, and evaluated antioxidant enzyme activities of these two varieties based on their performance under environmentally relevant, elevated O(3) conditions. The experiment was conducte...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1023/A:1026500911237
更新日期:2000-01-01 00:00:00
abstract::Oxygen may enhance CO2-saturated photosynthesis in intact leaves, which display the Warburg effect when illuminated at the current atmospheric level of CO2 and O2, of about 350 microl l(-1) and 21%, respectively. The magnitude of the stimulation depends on irradiance. The K(M)(O2) of the stimulation is 128 microM (10....
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-006-9050-3
更新日期:2006-06-01 00:00:00
abstract::Modified forms of the D1 protein with deletions in lumen-exposed regions, were constructed in the cyanobacterium Synechocystis 6803 using site-directed mutagenesis. Integration and stability of the mutated D1 proteins in the thylakoid membrane were studied by immunoblot and pulse-chase analyses. It was found that in Δ...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00117663
更新日期:1996-08-01 00:00:00
abstract::The electronic structure of a Mn(II) ion bound to highly oxidizing reaction centers of Rhodobacter sphaeroides was studied in a mutant modified to possess a metal binding site at a location comparable to the Mn4Ca cluster of photosystem II. The Mn-binding site of the previously described mutant, M2, contains three car...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-013-9887-1
更新日期:2014-05-01 00:00:00
abstract::A pigment system containing carotenoids and oxidised reaction centre pigments is present in chromatophores of Rhodospirillum rubrum and this pigment system may cause fluorescence quenching when a still unidentified chromatophore component is in its oxidised state. Besides by its action spectrum, this pigment system is...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00018376
更新日期:1984-03-01 00:00:00
abstract::Treatment of lyophilized thylakoid membranes of the thermophilic cyanobacterium Synechococcus sp. with n-heptane for 6 h resulted in marked changes in the pattern of photosystem I reaction center complexes resolved by sodium dodecylsulfate-polyacrylamide gel electrophoresis. CP1-a, which consists of two large subunits...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00117671
更新日期:1987-01-01 00:00:00
abstract::The crystallization of a given protein is a hard task being even more complicated when the protein shows a hydrophobic behavior. In the case of photosynthetic proteins, the difficulty of the experiments increased due to the high light sensitivity. Aqueous solutions of photosystem II core complex (OEC PSII) of Pisum sa...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-007-9131-y
更新日期:2006-12-01 00:00:00
abstract::Plant terpenoids are among the most diverse group of naturally-occurring organic compounds known, and several are used in contemporary consumer products. Terpene synthase enzymes catalyze complex rearrangements of carbon skeleton precursors to yield thousands of unique chemical structures that range in size from the s...
journal_title:Photosynthesis research
pub_type: 杂志文章,评审
doi:10.1007/s11120-014-9979-6
更新日期:2015-03-01 00:00:00
abstract::Inorganic phosphate participates in many fundamental processes within the plant cell. Its broad influence on plant metabolism is related to such key operations as metabolite transport, enzyme regulation and carbohydrate metabolism in general. This review discusses these topics with special emphasis on the role assigne...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/BF00016551
更新日期:1993-03-01 00:00:00
abstract::To understand design principles for assembling photosynthetic biohybrids that incorporate precisely-controlled sites for electron injection into redox enzyme cofactor arrays, we investigated the influence of chirality in assembly of the photosensitizer ruthenium(II)bis(2,2'-bipyridine)(4-bromomethyl-4'-methyl-2,2'-bip...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-019-00697-8
更新日期:2020-02-01 00:00:00
abstract::The afterglow (AG) band of thermoluminescence (TL) has been investigated in leaves of Arabidopsis thaliana. Excitation of dark-adapted leaves with two saturating single turn-over flashes induced the appearance of a complex TL glow curve that could be well simulated by three components: the two components, B1 and B2, o...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-004-7311-6
更新日期:2005-06-01 00:00:00
abstract::Biological water oxidation, performed by a single enzyme, photosystem II, is a central research topic not only in understanding the photosynthetic apparatus but also for the development of water splitting catalysts for technological applications. Great progress has been made in this endeavor following the report of a ...
journal_title:Photosynthesis research
pub_type: 杂志文章,评审
doi:10.1007/s11120-019-00648-3
更新日期:2019-10-01 00:00:00
abstract::Heliobacteria contain Type I reaction centers (RCs) and a homodimeric core, but unlike green sulfur bacteria, they do not contain an extended antenna system. Given their simplicity, the heliobacterial RC (HbRC) should be ideal for the study of a prototypical homodimeric RC. However, there exist enormous gaps in our kn...
journal_title:Photosynthesis research
pub_type: 杂志文章,评审
doi:10.1007/s11120-007-9162-4
更新日期:2007-04-01 00:00:00
abstract::Envelope membranes were isolated by sucrose density gradient floatation centrifugation from the homogenate of cyanelles prepared from Cyanophora paradoxa. Two yellow bands were separated after 40 h of centrifugation. The buoyant density of one of the two fractions (fraction Y2) coincided with that of inner envelope me...
journal_title:Photosynthesis research
pub_type: 杂志文章
doi:10.1007/s11120-007-9156-2
更新日期:2007-07-01 00:00:00