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Li Z, Zhou C, Zhao S, Zhang J, Liu X, Sang M, Qin X, Yang Y, Han G, Kuang T, Shen JR, Wang W. Structural and functional properties of different types of siphonous LHCII trimers from an intertidal green alga Bryopsis corticulans. Structure 2023; 31:1247-1258.e3. [PMID: 37633266 DOI: 10.1016/j.str.2023.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/27/2023] [Accepted: 08/01/2023] [Indexed: 08/28/2023]
Abstract
Light-harvesting complexes of photosystem II (LHCIIs) in green algae and plants are vital antenna apparatus for light harvesting, energy transfer, and photoprotection. Here we determined the structure of a siphonous-type LHCII trimer from the intertidal green alga Bryopsis corticulans by X-ray crystallography and cryo-electron microscopy (cryo-EM), and analyzed its functional properties by spectral analysis. The Bryopsis LHCII (Bry-LHCII) structures in both homotrimeric and heterotrimeric form show that green light-absorbing siphonaxanthin and siphonein occupied the sites of lutein and violaxanthin in plant LHCII, and two extra chlorophylls (Chls) b replaced Chls a. Binding of these pigments expands the blue-green light absorption of B. corticulans in the tidal zone. We observed differences between the Bry-LHCII homotrimer crystal and cryo-EM structures, and also between Bry-LHCII homotrimer and heterotrimer cryo-EM structures. These conformational changes may reflect the flexibility of Bry-LHCII, which may be required to adapt to light fluctuations from tidal rhythms.
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Affiliation(s)
- Zhenhua Li
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Science, Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Cuicui Zhou
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Science, Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Songhao Zhao
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Science, Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Jinyang Zhang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Science, Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Xueyang Liu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Science, Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Min Sang
- China National Botanical Garden, Beijing 100093, China
| | - Xiaochun Qin
- School of Biological Science and Technology, University of Jinan, Jinan 250022, China
| | - Yanyan Yang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China
| | - Guangye Han
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China
| | - Tingyun Kuang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China
| | - Jian-Ren Shen
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China; Research Institute for Interdisciplinary Science, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
| | - Wenda Wang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; China National Botanical Garden, Beijing 100093, China.
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Barreto Filho MM, Vieira HH, Morris JJ, Bagatini IL. Species-specific effects and the ecological role of programmed cell death in the microalgae Ankistrodesmus (Sphaeropleales, Selenastraceae). Biol Lett 2022; 18:20220259. [PMID: 36259168 PMCID: PMC9579752 DOI: 10.1098/rsbl.2022.0259] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 09/27/2022] [Indexed: 11/12/2022] Open
Abstract
Reports of programmed cell death (PCD) in phytoplankton raise questions about the ecological evolutionary role of cell death in these organisms. We induced PCD by nitrogen deprivation and unregulated cell death (non-PCD) in one strain of the green microalga Ankistrodesmus densus and investigated the effects of the cell death supernatants on phylogenetically related co-occurring organisms using growth rates and maximum biomass as proxies of fitness. PCD-released materials from A. densus CCMA-UFSCar-3 significantly increased growth rates of two conspecific strains compared to healthy culture (HC) supernatants and improved the maximum biomass of all A. densus strains compared to related species. Although growth rates of non-A. densus with PCD supernatants were not statistically different from HC treatment, biomass gain was significantly reduced. Thus, the organic substances released by PCD, possibly nitrogenous compounds, could promote conspecific growth. These results support the argument that PCD may differentiate species or subtypes and increases inclusive fitness in this model unicellular chlorophyte. Further research, however, is needed to identify the responsible molecules and how they interact with cells to provide the PCD benefits.
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Affiliation(s)
- Marcelo M. Barreto Filho
- Laboratory of Phycology, Department of Botany, Federal University of São Carlos (UFSCar), Brazil
- Programa de Pós-Graduação em Ecologia e Recursos Naturais (PPGERN), UFSCar, São Carlos, São Paulo, Brazil
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Helena H. Vieira
- Laboratory of Phycology, Department of Botany, Federal University of São Carlos (UFSCar), Brazil
- Hydrobiologický Ústav, Biologické centre AV ČR, v.v.i, České Budějovice, Czechia
| | - J. Jeffrey Morris
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Inessa L. Bagatini
- Laboratory of Phycology, Department of Botany, Federal University of São Carlos (UFSCar), Brazil
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Li L, Li F, Wang Y, Yang C, Lu C, Liu C, Sun R. An innovative artificial photosystem II constructed from PSII core of Thermosynechococcus vulcanus and LHCII of Pisum sativum - A new approach for studying the function of photosynthetic antenna. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 154:160-170. [PMID: 32563040 DOI: 10.1016/j.plaphy.2020.05.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 05/23/2020] [Accepted: 05/25/2020] [Indexed: 06/11/2023]
Abstract
In photosynthesis, the antenna system captures solar energy and transfers the excitations to photosystem II (PSII) core complex where charge separation, water splitting and oxygen evolution occur. In the evolution of photosynthesis from aquatic to terrestrial environments, the structure of PSII core complex was highly conserved while a variety of antenna forms became differentiated. In order to study the principles for energy transport from antenna to the PSII reaction center, we have explored whether the major light harvesting complex of PSII (LHCII) of higher plants can transfer energy to the cyanobacteria PSII core complexes (CC). For this purpose, LHCII from pea and CC from Thermosynechococcus vulcanus were isolated and co-reconstituted into liposome at LHCII:CC molar ratios of 2:1, 4:1 and 6:1, respectively. Chemical-cross linking followed by LC-MS/MS analysis confirmed the biochemical interaction between LHCII and CC in the liposome membrane. The analyses of 77 K fluorescence emission spectra and antenna cross section of PSII indicated that LHCII can transfer energy directly to the cyanobacterial CC. The study has laid the basis for further research on the mechanism of energy transfer from LHCII to PSII CC. This result may also open a new possibility for design and development of new artificial PSII in the application of solar energy conversion.
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Affiliation(s)
- Ling Li
- Key Laboratory of Plant Resources/Beijing Botanical Garden, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China; University of Chinese Academy of Sciences, Yuquan Road 19A, Beijing, 100049, China
| | - Fei Li
- Key Laboratory of Plant Resources/Beijing Botanical Garden, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China; University of Chinese Academy of Sciences, Yuquan Road 19A, Beijing, 100049, China
| | - Yue Wang
- Key Laboratory of Plant Resources/Beijing Botanical Garden, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China; University of Chinese Academy of Sciences, Yuquan Road 19A, Beijing, 100049, China
| | - Chunhong Yang
- Key Laboratory of Plant Resources/Beijing Botanical Garden, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China; University of Chinese Academy of Sciences, Yuquan Road 19A, Beijing, 100049, China; Qingdao Institute, Shanghai Institute of Technological Physics, Chinese Academy of Sciences, Binhai Road 50, Qingdao, 264000, China.
| | - Congming Lu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong, 271018, China
| | - Cheng Liu
- Key Laboratory of Plant Resources/Beijing Botanical Garden, Institute of Botany, the Chinese Academy of Sciences, Beijing, 100093, China; University of Chinese Academy of Sciences, Yuquan Road 19A, Beijing, 100049, China.
| | - Ruixue Sun
- Qingdao Institute, Shanghai Institute of Technological Physics, Chinese Academy of Sciences, Binhai Road 50, Qingdao, 264000, China.
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Lingvay M, Akhtar P, Sebők-Nagy K, Páli T, Lambrev PH. Photobleaching of Chlorophyll in Light-Harvesting Complex II Increases in Lipid Environment. FRONTIERS IN PLANT SCIENCE 2020; 11:849. [PMID: 32670321 PMCID: PMC7327537 DOI: 10.3389/fpls.2020.00849] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 05/26/2020] [Indexed: 05/18/2023]
Abstract
Excess light causes damage to the photosynthetic apparatus of plants and algae primarily via reactive oxygen species. Singlet oxygen can be formed by interaction of chlorophyll (Chl) triplet states, especially in the Photosystem II reaction center, with oxygen. Whether Chls in the light-harvesting antenna complexes play direct role in oxidative photodamage is less clear. In this work, light-induced photobleaching of Chls in the major trimeric light-harvesting complex II (LHCII) is investigated in different molecular environments - protein aggregates, embedded in detergent micelles or in reconstituted membranes (proteoliposomes). The effects of intense light treatment were analyzed by absorption and circular dichroism spectroscopy, steady-state and time-resolved fluorescence and EPR spectroscopy. The rate and quantum yield of photobleaching was estimated from the light-induced Chl absorption changes. Photobleaching occurred mainly in Chl a and was accompanied by strong fluorescence quenching of the remaining unbleached Chls. The rate of photobleaching increased by 140% when LHCII was embedded in lipid membranes, compared to detergent-solubilized LHCII. Removing oxygen from the medium or adding antioxidants largely suppressed the bleaching, confirming its oxidative mechanism. Singlet oxygen formation was monitored by EPR spectroscopy using spin traps and spin labels to detect singlet oxygen directly and indirectly, respectively. The quantum yield of Chl a photobleaching in membranes and detergent was found to be 3.4 × 10-5 and 1.4 × 10-5, respectively. These values compare well with the yields of ROS production estimated from spin-trap EPR spectroscopy (around 4 × 10-5 and 2 × 10-5). A kinetic model is proposed, quantifying the generation of Chl and carotenoid triplet states and singlet oxygen. The high quantum yield of photobleaching, especially in the lipid membrane, suggest that direct photodamage of the antenna occurs with rates relevant to photoinhibition in vivo. The results represent further evidence that the molecular environment of LHCII has profound impact on its functional characteristics, including, among others, the susceptibility to photodamage.
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Affiliation(s)
- Mónika Lingvay
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
- Doctoral School of Physics, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Parveen Akhtar
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
| | | | - Tibor Páli
- Institute of Biophysics, Biological Research Centre, Szeged, Hungary
| | - Petar H. Lambrev
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
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van den Berg TE, van Oort B, Croce R. Light-harvesting complexes of Botryococcus braunii. PHOTOSYNTHESIS RESEARCH 2018; 135:191-201. [PMID: 28551868 PMCID: PMC5783996 DOI: 10.1007/s11120-017-0405-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 05/20/2017] [Indexed: 05/03/2023]
Abstract
The colonial green alga Botryococcus braunii (BB) is a potential source of biofuel due to its natural high hydrocarbon content. Unfortunately, its slow growth limits its biotechnological potential. Understanding its photosynthetic machinery could help to identify possible growth limitations. Here, we present the first study on BB light-harvesting complexes (LHCs). We purified two LHC fractions containing the complexes in monomeric and trimeric form. Both fractions contained at least two proteins with molecular weight (MW) around 25 kDa. The chlorophyll composition is similar to that of the LHCII of plants; in contrast, the main xanthophyll is loroxanthin, which substitutes lutein in most binding sites. Circular dichroism and 77 K absorption spectra lack typical differences between monomeric and trimeric complexes, suggesting that intermonomer interactions do not play a role in BB LHCs. This is in agreement with the low stability of the BB LHCII trimers as compared to the complexes of plants, which could be related to loroxanthin binding in the central (L1 and L2) binding sites. The properties of BB LHCII are similar to those of plant LHCII, indicating a similar pigment organization. Differences are a higher content of red chlorophyll a, similar to plant Lhcb3. These differences and the different Xan composition had no effect on excitation energy transfer or fluorescence lifetimes, which were similar to plant LHCII.
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Affiliation(s)
- Tomas E van den Berg
- Biophysics of Photosynthesis, Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, 1081 HV, Amsterdam, The Netherlands
| | - Bart van Oort
- Biophysics of Photosynthesis, Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, 1081 HV, Amsterdam, The Netherlands
| | - Roberta Croce
- Biophysics of Photosynthesis, Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, 1081 HV, Amsterdam, The Netherlands.
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Karlický V, Kurasová I, Ptáčková B, Večeřová K, Urban O, Špunda V. Enhanced thermal stability of the thylakoid membranes from spruce. A comparison with selected angiosperms. PHOTOSYNTHESIS RESEARCH 2016; 130:357-371. [PMID: 27154572 DOI: 10.1007/s11120-016-0269-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 04/25/2016] [Indexed: 06/05/2023]
Abstract
Recently, we have found that thermal stability of photosystem II (PSII) photochemistry in spruce needles is higher than in other plants (barley, beech) cultivated under the same temperatures. In this work, temperature dependences of various characteristics of PSII organization were studied in order to obtain complex information on the thermal stability of PSII function and organization in spruce. Temperature dependency of circular dichroism spectra revealed by about 6 °C higher thermal stability of macrodomain organization in spruce thylakoid membranes in comparison with Arabidopsis and barley ones; however, thermal disintegration of light-harvesting complex of PSII did not significantly differ among the species studied. These results thus indicate that thermal stability of PSII macro-organization in spruce thylakoid membranes is enhanced to a similar extent as thermal stability of PSII photochemistry. Clear-native polyacrylamide gel electrophoresis of preheated thylakoids demonstrated that among the separated pigment-protein complexes, only PSII supercomplexes (SCs) revealed considerably higher thermal stability in spruce thylakoids as compared to Arabidopsis and barley ones. Hence we suggest that higher thermal stability of PSII macro-organization of spruce is influenced by the maintenance of PSII SCs in the thylakoid membrane. In addition, we discuss possible effects of different PSII organizations and lipid compositions on the thermal stability of spruce thylakoid membranes.
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Affiliation(s)
- Václav Karlický
- Faculty of Science, Ostrava University, 30. dubna 22, 701 03, Ostrava 1, Czech Republic.
- Global Change Research Institute CAS, Bělidla 986/4a, 603 00, Brno, Czech Republic.
| | - Irena Kurasová
- Faculty of Science, Ostrava University, 30. dubna 22, 701 03, Ostrava 1, Czech Republic
- Global Change Research Institute CAS, Bělidla 986/4a, 603 00, Brno, Czech Republic
| | - Božena Ptáčková
- Faculty of Science, Ostrava University, 30. dubna 22, 701 03, Ostrava 1, Czech Republic
| | - Kristýna Večeřová
- Global Change Research Institute CAS, Bělidla 986/4a, 603 00, Brno, Czech Republic
| | - Otmar Urban
- Global Change Research Institute CAS, Bělidla 986/4a, 603 00, Brno, Czech Republic
| | - Vladimír Špunda
- Faculty of Science, Ostrava University, 30. dubna 22, 701 03, Ostrava 1, Czech Republic
- Global Change Research Institute CAS, Bělidla 986/4a, 603 00, Brno, Czech Republic
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Liu W, Tu W, Liu Y, Sun R, Liu C, Yang C. The N-terminal domain of Lhcb proteins is critical for recognition of the LHCII kinase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:79-88. [DOI: 10.1016/j.bbabio.2015.10.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 10/06/2015] [Accepted: 10/11/2015] [Indexed: 12/14/2022]
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Chen L, Liu C, Hu R, Feng J, Wang S, Li S, Yang C, Yang G. Two photon absorption energy transfer in the light-harvesting complex of photosystem II (LHC-II) modified with organic boron dye. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 128:295-299. [PMID: 24681315 DOI: 10.1016/j.saa.2014.02.166] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 02/19/2014] [Accepted: 02/24/2014] [Indexed: 06/03/2023]
Abstract
The plant light-harvesting complexes of photosystem II (LHC-II) play important roles in collecting solar energy and transferring the energy to the reaction centers of photosystems I and II. A two photon absorption compound, 4-(bromomethyl)-N-(4-(dimesitylboryl)phenyl)-N-phenylaniline (DMDP-CH2Br), was synthesized and covalently linked to the LHC-II in formation of a LHC-II-dye complex, which still maintained the biological activity of LHC-II system. Under irradiation with femtosecond laser pulses at 754 nm, the LHC-II-dye complex can absorb two photons of the laser light effectively compared with the wild type LHC-II. The absorbed excitation energy is then transferred to chlorophyll a with an obvious fluorescence enhancement. The results may be interesting and give potentials for developing hybrid photosystems.
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Affiliation(s)
- Li Chen
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Cheng Liu
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Rui Hu
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Jiao Feng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Shuangqing Wang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Shayu Li
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Chunhong Yang
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
| | - Guoqiang Yang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
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Photosynthetic responses of Oryza sativa L. seedlings to cadmium stress: physiological, biochemical and ultrastructural analyses. Biometals 2014; 27:389-401. [DOI: 10.1007/s10534-014-9720-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 02/12/2014] [Indexed: 10/25/2022]
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10
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Durand PM, Rashidi A, Michod RE. How an Organism Dies Affects the Fitness of Its Neighbors. Am Nat 2011; 177:224-32. [DOI: 10.1086/657686] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Kochubey SM. Changes in antenna of photosystem II induced by short-term heating. PHOTOSYNTHESIS RESEARCH 2010; 106:239-46. [PMID: 21140217 DOI: 10.1007/s11120-010-9599-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Accepted: 11/12/2010] [Indexed: 05/30/2023]
Abstract
Changes in antenna of photosystem II, induced by short-term heating, were studied using characteristics of a short-wavelength band in low-temperature fluorescence spectra (77 K) of pea chloroplasts. Heating for 5 min was carried out at 25 and 45°C in the darkness or in the presence of white light with intensity of 260 or 1,400 μmol/m(2)s. Most modes of thermal treating induced a decrease in integral intensity of the band and an increase of its half-width. The changes were more prominent at high-temperature heating. The second derivative of the contour of a short-wavelength band showed its three components around 680, 685, and 693 nm, the first of which belongs to emission of the outer antenna of Photosystem II, and the other two to its inner antenna. As the fourth derivative shows, high-temperature heating in the presence of light evokes an appearance of some additional components in a short-wavelength region (654, 658, 661, 666, 672, and 675 nm) as well as of two additional components, 682 and 689 nm, in the region of 685-nm peak. Two subcomponents, 692 and 694 nm, can be detected in the 693-nm component. The results are discussed on the basis of the data concerning energy levels and pathways of energy transfer in pigment-protein complexes of the outer and the inner antennas of photosystem II. It is assumed that a protective role of low light relates to inducing of an essential disarrangement in the outer and the inner antennas and of a subsequent decrease in energy funneling to reaction centers, which, in turn, lowers the extent of photoinhibition.
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Affiliation(s)
- Svetlana M Kochubey
- Institute of Plant Physiology, National Academy of Sciences of Ukraine, Vasylkivska Str. 31/17, Kiev, Ukraine.
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Peneva K, Gundlach K, Herrmann A, Paulsen H, Müllen K. Site-specific incorporation of perylene into an N-terminally modified light-harvesting complex II. Org Biomol Chem 2010; 8:4823-6. [DOI: 10.1039/c0ob00492h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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