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Grossman A, Sanz-Luque E, Yi H, Yang W. Building the GreenCut2 suite of proteins to unmask photosynthetic function and regulation. Microbiology (Reading) 2019; 165:697-718. [DOI: 10.1099/mic.0.000788] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Arthur Grossman
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Emanuel Sanz-Luque
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Heng Yi
- Key Laboratory of Photobiology, Institute of Botany (CAS), Beijing, PR China
- University of Chinese Academy of Sciences, Beijing, PR China
| | - Wenqiang Yang
- Key Laboratory of Photobiology, Institute of Botany (CAS), Beijing, PR China
- University of Chinese Academy of Sciences, Beijing, PR China
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102
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Milić JV, Diederich F. The Quest for Molecular Grippers: Photo‐Electric Control of Molecular Gripping Machinery. Chemistry 2019; 25:8440-8452. [DOI: 10.1002/chem.201900852] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 03/25/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Jovana V. Milić
- Laboratory of Photonics and InterfacesÉcole Polytechnique Fédéralé de Lausanne 1015 Lausanne Switzerland
| | - François Diederich
- Department of Chemistry and Applied BiosciencesETH Zurich Vladimir-Prelog-Weg 3 8010 Zurich Switzerland
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103
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Cafferty BJ, Yuan L, Baghbanzadeh M, Rappoport D, Beyzavi MH, Whitesides GM. Charge Transport through Self‐Assembled Monolayers of Monoterpenoids. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201902997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Brian J. Cafferty
- Department of Chemistry and Chemical Biology Harvard University 12 Oxford Street Cambridge MA 02138 USA
| | - Li Yuan
- Department of Chemistry and Chemical Biology Harvard University 12 Oxford Street Cambridge MA 02138 USA
| | - Mostafa Baghbanzadeh
- Department of Chemistry and Chemical Biology Harvard University 12 Oxford Street Cambridge MA 02138 USA
| | - Dmitrij Rappoport
- Department of Chemistry and Chemical Biology Harvard University 12 Oxford Street Cambridge MA 02138 USA
| | - M. Hassan Beyzavi
- Department of Chemistry and Chemical Biology Harvard University 12 Oxford Street Cambridge MA 02138 USA
- Current address: Department of Chemistry and Biochemistry University of Arkansas Fayetteville AR 72701 USA
| | - George M. Whitesides
- Department of Chemistry and Chemical Biology Harvard University 12 Oxford Street Cambridge MA 02138 USA
- Kalvi Institute for Bionano Science and Technology Harvard University 29 Oxford Street Cambridge MA 02138 USA
- Wyss Institute for Biologically Inspired Engineering Harvard University 60 Oxford Street Cambridge MA 02138 USA
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104
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Cafferty BJ, Yuan L, Baghbanzadeh M, Rappoport D, Beyzavi MH, Whitesides GM. Charge Transport through Self-Assembled Monolayers of Monoterpenoids. Angew Chem Int Ed Engl 2019; 58:8097-8102. [PMID: 30989746 DOI: 10.1002/anie.201902997] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Indexed: 11/08/2022]
Abstract
The nature of the processes at the origin of life that selected specific classes of molecules for broad incorporation into cells is controversial. Among those classes selected were polyisoprenoids and their derivatives. This paper tests the hypothesis that polyisoprenoids were early contributors to membranes in part because they (or their derivatives) could facilitate charge transport by quantum tunneling. It measures charge transport across self-assembled monolayers (SAMs) of carboxyl-terminated monoterpenoids (O2 C(C9 HX)) and alkanoates (O2 C(C7 HX)) with different degrees of unsaturation, supported on silver (AgTS ) bottom electrodes, with Ga2 O3 /EGaIn top electrodes. Measurements of current density of SAMs of linear length-matched hydrocarbons-both saturated and unsaturated-show that completely unsaturated molecules transport charge faster than those that are completely saturated by approximately a factor of ten. This increase in relative rates of charge transport correlates with the number of carbon-carbon double bonds, but not with the extent of conjugation. These results suggest that polyisoprenoids-even fully unsaturated-are not sufficiently good tunneling conductors for their conductivity to have favored them as building blocks in the prebiotic world.
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Affiliation(s)
- Brian J Cafferty
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - Li Yuan
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - Mostafa Baghbanzadeh
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - Dmitrij Rappoport
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - M Hassan Beyzavi
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA.,Current address: Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR, 72701, USA
| | - George M Whitesides
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA.,Kalvi Institute for Bionano Science and Technology, Harvard University, 29 Oxford Street, Cambridge, MA, 02138, USA.,Wyss Institute for Biologically Inspired Engineering, Harvard University, 60 Oxford Street, Cambridge, MA, 02138, USA
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105
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Perin G, Bellan A, Bernardi A, Bezzo F, Morosinotto T. The potential of quantitative models to improve microalgae photosynthetic efficiency. PHYSIOLOGIA PLANTARUM 2019; 166:380-391. [PMID: 30578540 DOI: 10.1111/ppl.12915] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 12/14/2018] [Accepted: 12/18/2018] [Indexed: 06/09/2023]
Abstract
The massive increase in carbon dioxide concentration in the atmosphere driven by human activities is causing huge negative consequences and new sustainable sources of energy, food and materials are highly needed. Algae are unicellular photosynthetic microorganisms that can provide a highly strategic contribution to this challenge as alternative source of biomass to complement crops cultivation. Algae industrial cultures are commonly limited by light availability, and biomass accumulation is strongly dependent on their photon-to-biomass conversion efficiency. Investigation of algae photosynthetic metabolism is thus strategic for the generation of more efficient strains with higher productivity. Algae are cultivated at industrial scale in conditions highly different from the natural niches they adapted to and strains development efforts must fully consider the seminal influence on productivity of regulatory mechanism of photosynthesis as well as of cultivation parameters like cells concentration, light distribution in the culture, mixing, nutrients and carbon dioxide availability. In this review we will focus in particular on how mathematical models can account for the complex influence of all environmental parameters and can be exploited for development of improved algae strains.
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Affiliation(s)
- Giorgio Perin
- Department of Biology, University of Padova, Via Ugo Bassi 58/B 35131, Padova, Italy
| | - Alessandra Bellan
- Department of Biology, University of Padova, Via Ugo Bassi 58/B 35131, Padova, Italy
| | - Andrea Bernardi
- Department of Industrial Engineering, University of Padova, Via Marzolo 9 35131, Padova, Italy
- Centre for Process Systems Engineering, Department of Chemical Engineering, Imperial College London, SW7 2AZ, London, UK
| | - Fabrizio Bezzo
- Department of Industrial Engineering, University of Padova, Via Marzolo 9 35131, Padova, Italy
| | - Tomas Morosinotto
- Department of Biology, University of Padova, Via Ugo Bassi 58/B 35131, Padova, Italy
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106
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Nawrocki W, Bailleul B, Cardol P, Rappaport F, Wollman FA, Joliot P. Maximal cyclic electron flow rate is independent of PGRL1 in Chlamydomonas. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1860:425-432. [DOI: 10.1016/j.bbabio.2019.01.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Revised: 12/08/2018] [Accepted: 01/25/2019] [Indexed: 11/30/2022]
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107
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Sello S, Meneghesso A, Alboresi A, Baldan B, Morosinotto T. Plant biodiversity and regulation of photosynthesis in the natural environment. PLANTA 2019; 249:1217-1228. [PMID: 30607502 DOI: 10.1007/s00425-018-03077-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 12/19/2018] [Indexed: 06/09/2023]
Abstract
Investigation of photosynthesis regulation in different plant groups exposed to variable conditions showed that all species have similar photosynthetic electron transport modulation while excess energy dissipation is species specific. Photosynthesis is regulated in response to dynamic environmental conditions to satisfy plant metabolic demands while also avoiding possible over-excitation of the electron transport chain and the generation of harmful reactive oxygen species. Photosynthetic organisms evolved several mechanisms to modulate light harvesting and electron transport efficiency to respond to conditions changing at different timescales, going from fast sun flecks to slow seasonal variations. These regulatory mechanisms changed during evolution of photosynthetic organisms, also adapting to various ecological niches, making the investigation of plant biodiversity highly valuable to uncover conserved traits and plasticity of photosynthetic regulation and complement studies on model species. In this work, a set of plants belonging to different genera of angiosperms, gymnosperms, ferns and lycophytes were investigated by monitoring their photosynthetic parameters in different seasons looking for common trends and differences. In all plants, analysed photosynthetic electron transport rate was found to be modulated by growth light intensity, ensuring a balance between available energy and photochemical capacity. Growth light also influenced the threshold where heat dissipation of excitation energy, a mechanism called non-photochemical quenching (NPQ), was activated. On the contrary, NPQ amplitude did not correlate with light intensity experienced by the plants but was a species-specific feature. The zeaxanthin-dependent component of NPQ, qZ, was found to be the most variable in different plants and its modulation influenced the intensity and the kinetic properties of the response.
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Affiliation(s)
- Simone Sello
- Department of Biology, University of Padova, Via Ugo Bassi 58B, 35121, Padua, Italy
- Botanical Garden, University of Padova, 35123, Padua, Italy
| | - Andrea Meneghesso
- Department of Biology, University of Padova, Via Ugo Bassi 58B, 35121, Padua, Italy
| | - Alessandro Alboresi
- Department of Biology, University of Padova, Via Ugo Bassi 58B, 35121, Padua, Italy
- Botanical Garden, University of Padova, 35123, Padua, Italy
| | - Barbara Baldan
- Department of Biology, University of Padova, Via Ugo Bassi 58B, 35121, Padua, Italy
- Botanical Garden, University of Padova, 35123, Padua, Italy
| | - Tomas Morosinotto
- Department of Biology, University of Padova, Via Ugo Bassi 58B, 35121, Padua, Italy.
- Botanical Garden, University of Padova, 35123, Padua, Italy.
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108
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Rast A, Schaffer M, Albert S, Wan W, Pfeffer S, Beck F, Plitzko JM, Nickelsen J, Engel BD. Biogenic regions of cyanobacterial thylakoids form contact sites with the plasma membrane. NATURE PLANTS 2019; 5:436-446. [PMID: 30962530 DOI: 10.1038/s41477-019-0399-7] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 03/04/2019] [Indexed: 05/20/2023]
Abstract
Little is known about how the photosynthetic machinery is arranged in time and space during the biogenesis of thylakoid membranes. Using in situ cryo-electron tomography to image the three-dimensional architecture of the cyanobacterium Synechocystis, we observed that the tips of multiple thylakoids merge to form a substructure called the 'convergence membrane'. This high-curvature membrane comes into close contact with the plasma membrane at discrete sites. We generated subtomogram averages of 70S ribosomes and array-forming phycobilisomes, then mapped these structures onto the native membrane architecture as markers for protein synthesis and photosynthesis, respectively. This molecular localization identified two distinct biogenic regions in the thylakoid network: thylakoids facing the cytosolic interior of the cell that were associated with both marker complexes, and convergence membranes that were decorated by ribosomes but not phycobilisomes. We propose that the convergence membranes perform a specialized biogenic function, coupling the synthesis of thylakoid proteins with the integration of cofactors from the plasma membrane and the periplasmic space.
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Affiliation(s)
- Anna Rast
- Department of Molecular Plant Sciences, Ludwig-Maximilians-University Munich, Martinsried, Germany
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Miroslava Schaffer
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Sahradha Albert
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - William Wan
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Stefan Pfeffer
- Center for Molecular Biology, University of Heidelberg, Heidelberg, Germany
| | - Florian Beck
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jürgen M Plitzko
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jörg Nickelsen
- Department of Molecular Plant Sciences, Ludwig-Maximilians-University Munich, Martinsried, Germany.
| | - Benjamin D Engel
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany.
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109
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Benkov MA, Yatsenko AM, Tikhonov AN. Light acclimation of shade-tolerant and sun-resistant Tradescantia species: photochemical activity of PSII and its sensitivity to heat treatment. PHOTOSYNTHESIS RESEARCH 2019; 139:203-214. [PMID: 29926255 DOI: 10.1007/s11120-018-0535-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 06/13/2018] [Indexed: 06/08/2023]
Abstract
In this work, we have compared photosynthetic characteristics of photosystem II (PSII) in Tradescantia leaves of two contrasting ecotypes grown under the low light (LL) and high light (HL) regimes during their entire growth period. Plants of the same genus, T. fluminensis (shade-tolerant) and T. sillamontana (sun-resistant), were cultivated at 50-125 µmol photons m-2 s-1 (LL) or at 875-1000 µmol photons m-2 s-1 (HL). Analyses of intrinsic PSII efficiency was based on measurements of fast chlorophyll (Chl) a fluorescence kinetics (the OJIP test). The fluorescence parameters Fv/Fm (variable fluorescence) and F0 (the initial level of fluorescence) in dark-adapted leaves were used to quantify the photochemical properties of PSII. Plants of different ecotypes showed different sustainability with respect to changes in the environmental light intensity and temperature treatment. The sun-resistant species T. sillamontana revealed the tolerance to variations in irradiation intensity, demonstrating constancy of maximum quantum efficiency of PSII upon variations of the growth light. In contrast to T. sillamontana, facultative shade species T. fluminensis demonstrated variability of PSII photochemical activity, depending on the growth light intensity. The susceptibility of T. fluminensis to solar stress was documented by a decrease in Fv/Fm and a rise of F0 during the long-term exposition of T. fluminensis to HL, indicating the loss of photochemical activity of PSII. The short-term (10 min) heat treatment of leaf cuttings caused inactivation of PSII. The temperature-dependent heating effects were different in T. fluminensis and T. sillamontana. Sun-resistant plants T. sillamontana acclimated to LL and HL displayed the same plots of Fv/Fm versus the treatment temperature (t), demonstrating a decrease in Fv/Fm at t ≥ 45 °C. The leaves of shadow-tolerant species T. fluminensis grown under the LL and HL conditions revealed different sensitivities to heat treatment. Plants grown under the solar stress conditions (HL) demonstrated a gradual decline of Fv/Fm at lower heating temperatures (t ≥ 25 °C), indicating the "fragility" of their PSII as compared to T. fluminensis grown at LL. Different responses of sun and shadow species of Tradescantia to growth light and heat treatment are discussed in the context of their biochemical and ecophysiological properties.
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Affiliation(s)
- Michael A Benkov
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Anton M Yatsenko
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Alexander N Tikhonov
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, Russia.
- N.M. Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Moscow, Russia.
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110
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Ptushenko VV, Zhigalova TV, Avercheva OV, Tikhonov AN. Three phases of energy-dependent induction of [Formula: see text] and Chl a fluorescence in Tradescantia fluminensis leaves. PHOTOSYNTHESIS RESEARCH 2019. [PMID: 29516232 DOI: 10.1007/s11120-018-0494-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
In plants, the short-term regulation (STR, seconds to minute time scale) of photosynthetic apparatus is associated with the energy-dependent control in the chloroplast electron transport, the distribution of light energy between photosystems (PS) II and I, activation/deactivation of the Calvin-Benson cycle (CBC) enzymes, and relocation of chloroplasts within the plant cell. In this work, using a dual-PAM technique for measuring the time-courses of P700 photooxidation and Chl a fluorescence, we have investigated the STR events in Tradescantia fluminensis leaves. The comparison of Chl a fluorescence and [Formula: see text] induction allowed us to investigate the contribution of the trans-thylakoid pH difference (ΔpH) to the STR events. Two parameters were used as the indicators of ΔpH generation: pH-dependent component of non-photochemical quenching of Chl a fluorescence, and pHin-dependent rate of electron transfer from plastoquinol (PQH2) to [Formula: see text] (via the Cyt b6f complex and plastocyanin). In dark-adapted leaves, kinetics of [Formula: see text] induction revealed three phases. Initial phase is characterized by rapid electron flow to [Formula: see text] (τ1/2 ~ 5-10 ms), which is likely related to cyclic electron flow around PSI, while the outflow of electrons from PSI is restricted by slow consumption of NADPH in the CBC. The light-induced generation of ΔpH and activation of the CBC promote photooxidation of P700 and concomitant retardation of [Formula: see text] reduction (τ1/2 ~ 20 ms). Prolonged illumination induces additional slowing down of electron transfer to [Formula: see text] (τ1/2 ≥ 30-35 ms). The latter effect is not accompanied by changes in the Chl a fluorescence parameters which are sensitive to ΔpH generation. We suggest the tentative explanation of the latter results by the reversal of Q-cycle, which causes the deceleration of PQH2 oxidation due to the back pressure of stromal reductants.
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Affiliation(s)
- Vasily V Ptushenko
- A.N.Belozersky Institute of Physical-Chemical Biology, M.V.Lomonosov Moscow State University, Moscow, Russia
- N.M.Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Moscow, Russia
| | | | - Olga V Avercheva
- Faculty of Biology, M.V.Lomonosov Moscow State University, Moscow, Russia
| | - Alexander N Tikhonov
- N.M.Emanuel Institute of Biochemical Physics of Russian Academy of Sciences, Moscow, Russia.
- Faculty of Physics, M.V.Lomonosov Moscow State University, Moscow, Russia.
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111
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Baldisserotto C, Sabia A, Ferroni L, Pancaldi S. Biological aspects and biotechnological potential of marine diatoms in relation to different light regimens. World J Microbiol Biotechnol 2019; 35:35. [PMID: 30712106 DOI: 10.1007/s11274-019-2607-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 01/27/2019] [Indexed: 11/25/2022]
Abstract
As major primary producers in marine environments, diatoms are considered a valuable feedstock of biologically active compounds for application in several biotechnological fields. Due to their metabolic plasticity, especially for light perception and use and in order to make microalgal production more environmentally sustainable, marine diatoms are considered good candidates for the large-scale cultivation. Among physical parameters, light plays a primary role. Even if sunlight is cost-effective, the employment of artificial light becomes a winning strategy if a high-value microalgal biomass is produced. Several researches on marine diatoms are designed to study the influence of different light regimens to increase biomass production enriched in biotechnologically high-value compounds (lipids, carotenoids, proteins, polysaccharides), or with emphasised photonic properties of the frustule.
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Affiliation(s)
- Costanza Baldisserotto
- Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este, 32, 44121, Ferrara, Italy
| | - Alessandra Sabia
- Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este, 32, 44121, Ferrara, Italy
| | - Lorenzo Ferroni
- Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este, 32, 44121, Ferrara, Italy
| | - Simonetta Pancaldi
- Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este, 32, 44121, Ferrara, Italy.
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112
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Bourbousse C, Barneche F, Laloi C. Plant Chromatin Catches the Sun. FRONTIERS IN PLANT SCIENCE 2019; 10:1728. [PMID: 32038692 PMCID: PMC6992579 DOI: 10.3389/fpls.2019.01728] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 12/09/2019] [Indexed: 05/08/2023]
Abstract
Plants use solar radiation as energy source for photosynthesis. They also take advantage of the information provided by the varying properties of sunlight, such as wavelength, orientation, and periodicity, to trigger physiological and developmental adaptations to a changing environment. After more than a century of research efforts in plant photobiology, multiple light signaling pathways converging onto chromatin-based mechanisms have now been identified, which in some instances play critical roles in plant phenotypic plasticity. In addition to locus-specific changes linked to transcription regulation, light signals impact higher-order chromatin organization. Here, we summarize current knowledge on how light can affect the global composition and the spatial distribution of chromatin domains. We introduce emerging questions on the functional links between light signaling and the epigenome, and further discuss how different chromatin regulatory layers may interconnect during plant adaptive responses to light.
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Affiliation(s)
- Clara Bourbousse
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, Université PSL, Paris, France
- *Correspondence: Clara Bourbousse, ; Fredy Barneche,
| | - Fredy Barneche
- Institut de Biologie de l'Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, Université PSL, Paris, France
- *Correspondence: Clara Bourbousse, ; Fredy Barneche,
| | - Christophe Laloi
- Aix Marseille Univ, CEA, CNRS, BIAM, Luminy Génétique et Biophysique des Plantes, Marseille, France
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113
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Alboresi A, Storti M, Morosinotto T. Balancing protection and efficiency in the regulation of photosynthetic electron transport across plant evolution. THE NEW PHYTOLOGIST 2019; 221:105-109. [PMID: 30084195 DOI: 10.1111/nph.15372] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 06/26/2018] [Indexed: 05/20/2023]
Abstract
Contents Summary 105 I. Introduction 105 II. Diversity of molecular mechanisms for regulation of photosynthetic electron transport 106 III. Role of FLVs in the regulation of photosynthesis in eukaryotes 107 IV. Why were FLVs lost in angiosperms? 108 V. Conclusions 108 Acknowledgements 109 References 109 SUMMARY: Photosynthetic electron transport requires continuous modulation to maintain the balance between light availability and metabolic demands. Multiple mechanisms for the regulation of electron transport have been identified and are unevenly distributed among photosynthetic organisms. Flavodiiron proteins (FLVs) influence photosynthetic electron transport by accepting electrons downstream of photosystem I to reduce oxygen to water. FLV activity has been demonstrated in cyanobacteria, green algae and mosses to be important in avoiding photosystem I overreduction upon changes in light intensity. FLV-encoding sequences were nevertheless lost during evolution by angiosperms, suggesting that these plants increased the efficiency of other mechanisms capable of accepting electrons from photosystem I, making the FLV activity for protection from overreduction superfluous or even detrimental for photosynthetic efficiency.
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Affiliation(s)
- Alessandro Alboresi
- Department of Biology, University of Padova, Via Ugo Bassi 58B, 35121, Padua, Italy
| | - Mattia Storti
- Department of Biology, University of Padova, Via Ugo Bassi 58B, 35121, Padua, Italy
| | - Tomas Morosinotto
- Department of Biology, University of Padova, Via Ugo Bassi 58B, 35121, Padua, Italy
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114
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Zhang Y, Shi M, Mao X, Kou Y, Liu J. Time-resolved carotenoid profiling and transcriptomic analysis reveal mechanism of carotenogenesis for astaxanthin synthesis in the oleaginous green alga Chromochloris zofingiensis. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:287. [PMID: 31890015 PMCID: PMC6913025 DOI: 10.1186/s13068-019-1626-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 12/04/2019] [Indexed: 05/03/2023]
Abstract
BACKGROUND Chromochloris zofingiensis is emerging as an industrially relevant alga given its robust growth for the production of lipids and astaxanthin, a value-added carotenoid with broad applications. Nevertheless, poor understanding of astaxanthin synthesis has limited engineering of this alga for rational improvements. RESULTS To reveal the molecular mechanism underlying astaxanthin accumulation in C. zofingiensis, here we conducted an integrated analysis by combining the time-resolved transcriptomes and carotenoid profiling in response to nitrogen deprivation (ND). A global response was triggered for C. zofingiensis to cope with the ND stress. Albeit the little variation in total carotenoid content, individual carotenoids responded differentially to ND: the primary carotenoids particularly lutein and β-carotene decreased, while the secondary carotenoids increased considerably, with astaxanthin and canthaxanthin being the most increased ones. The carotenogenesis pathways were reconstructed: ND had little effect on the carbon flux to carotenoid precursors, but stimulated astaxanthin biosynthesis while repressing lutein biosynthesis, thereby diverting the carotenoid flux from primary carotenoids to secondary carotenoids particularly astaxanthin. Comparison between C. zofingiensis and Haematococcus pluvialis revealed the distinctive mechanism of astaxanthin synthesis in C. zofingiensis. Furthermore, potential bottlenecks in astaxanthin synthesis were identified and possible engineering strategies were proposed for the alga. CONCLUSIONS Collectively, these findings shed light on distinctive mechanism of carotenogenesis for astaxanthin biosynthesis in C. zofingiensis, identify key functional enzymes and regulators with engineering potential and will benefit rational manipulation of this alga for improving nutritional traits.
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Affiliation(s)
- Yu Zhang
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Meicheng Shi
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Xuemei Mao
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Yaping Kou
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
| | - Jin Liu
- Laboratory for Algae Biotechnology & Innovation, College of Engineering, Peking University, Beijing, 100871 China
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115
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Moriwaki T, Falcioni R, Tanaka FAO, Cardoso KAK, Souza LA, Benedito E, Nanni MR, Bonato CM, Antunes WC. Nitrogen-improved photosynthesis quantum yield is driven by increased thylakoid density, enhancing green light absorption. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 278:1-11. [PMID: 30471722 DOI: 10.1016/j.plantsci.2018.10.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 10/11/2018] [Accepted: 10/15/2018] [Indexed: 05/22/2023]
Abstract
A nitrogen supply is necessary for all plants. The multifaceted reasons why this nutrient stimulates plant dry weight accumulation are assessed herein. We compared tomato plants grown in full sunlight and in low light environments under four N doses and evaluated plant growth, photosynthetic and calorimetric parameters, leaf anatomy, chloroplast transmission electron microscopy (TEM) and a high resolution profile of optical leaf properties. Increases in N supplies allow tomato plants to grow faster in low light environments (91.5% shading), displaying a robust light harvesting machinery and, consequently, improved light harvesting efficiency. Ultrastructurally, high N doses were associated to a high number of grana per chloroplast and greater thylakoid stacking, as well as high electrodensity by TEM. Robust photosynthetic machinery improves green light absorption, but not blue or red. In addition, low construction and dark respiration costs were related to improved total dry weight accumulation in shade conditions. By applying multivariate analyses, we conclude that improved green light absorbance, improved quantum yield and greater palisade parenchyma cell area are the primary components that drive increased plant growth under natural light-limited photosynthesis.
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Affiliation(s)
- Thaise Moriwaki
- Laboratório de Ecofisiologia Vegetal, Brazil; Universidade Estadual de Maringá (UEM), Brazil
| | - Renan Falcioni
- Laboratório de Ecofisiologia Vegetal, Brazil; Universidade Estadual de Maringá (UEM), Brazil
| | - Francisco André Ossamu Tanaka
- Departamento de Fitopatologia e Nematologia (LFN), Escola Superior de Agricultura, Luiz de Queiroz, Universidade de São Paulo (ESALQ - USP), Brazil
| | | | - L A Souza
- Universidade Estadual de Maringá (UEM), Brazil; Laboratório de Histotécnica Vegetal, Brazil
| | - Evanilde Benedito
- Universidade Estadual de Maringá (UEM), Brazil; Laboratório de Ecologia Energética, Brazil
| | - Marcos Rafael Nanni
- Universidade Estadual de Maringá (UEM), Brazil; Grupo Aplicado ao Levantamento e Espacialização dos Solos, Brazil
| | - Carlos Moacir Bonato
- Laboratório de Ecofisiologia Vegetal, Brazil; Universidade Estadual de Maringá (UEM), Brazil
| | - Werner Camargos Antunes
- Laboratório de Ecofisiologia Vegetal, Brazil; Universidade Estadual de Maringá (UEM), Brazil.
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116
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Albanese P, Manfredi M, Re A, Marengo E, Saracco G, Pagliano C. Thylakoid proteome modulation in pea plants grown at different irradiances: quantitative proteomic profiling in a non-model organism aided by transcriptomic data integration. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 96:786-800. [PMID: 30118564 DOI: 10.1111/tpj.14068] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 08/03/2018] [Accepted: 08/13/2018] [Indexed: 05/02/2023]
Abstract
Plant thylakoid membranes contain hundreds of proteins that closely interact to cope with ever-changing environmental conditions. We investigated how Pisum sativum L. (pea) grown at different irradiances optimizes light-use efficiency through the differential accumulation of thylakoid proteins. Thylakoid membranes from plants grown under low (LL), moderate (ML) and high (HL) light intensity were characterized by combining chlorophyll fluorescence measurements with quantitative label-free proteomic analysis. Protein sequences retrieved from available transcriptomic data considerably improved thylakoid proteome profiling, increasing the quantifiable proteins from 63 to 194. The experimental approach used also demonstrates that this integrative omics strategy is powerful for unravelling protein isoforms and functions that are still unknown in non-model organisms. We found that the different growth irradiances affect the electron transport kinetics but not the relative abundance of photosystems (PS) I and II. Two acclimation strategies were evident. The behaviour of plants acclimated to LL was compared at higher irradiances: (i) in ML, plants turn on photoprotective responses mostly modulating the PSII light-harvesting capacity, either accumulating Lhcb4.3 or favouring the xanthophyll cycle; (ii) in HL, plants reduce the pool of light-harvesting complex II and enhance the PSII repair cycle. When growing at ML and HL, plants accumulate ATP synthase, boosting both cyclic and linear electron transport by finely tuning the ΔpH across the membrane and optimizing protein trafficking by adjusting the thylakoid architecture. Our results provide a quantitative snapshot of how plants coordinate light harvesting, electron transport and protein synthesis by adjusting the thylakoid membrane proteome in a light-dependent manner.
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Affiliation(s)
- Pascal Albanese
- Applied Science and Technology Department-BioSolar Lab, Politecnico di Torino, Environment Park, Via Livorno 60, 10144, Torino, Italy
| | - Marcello Manfredi
- ISALIT-Department of Science and Technological Innovation, University of Eastern Piedmont, Viale T. Michel 11, 15121, Alessandria, Italy
- Department of Science and Technological Innovation, University of Eastern Piedmont, Viale T. Michel 11, 15121, Alessandria, Italy
| | - Angela Re
- Center for Sustainable Future Technologies-CSFT@POLITO, Istituto Italiano di Tecnologia, Corso Trento 21, 10129, Torino, Italy
| | - Emilio Marengo
- Department of Science and Technological Innovation, University of Eastern Piedmont, Viale T. Michel 11, 15121, Alessandria, Italy
| | - Guido Saracco
- Applied Science and Technology Department-BioSolar Lab, Politecnico di Torino, Environment Park, Via Livorno 60, 10144, Torino, Italy
| | - Cristina Pagliano
- Applied Science and Technology Department-BioSolar Lab, Politecnico di Torino, Environment Park, Via Livorno 60, 10144, Torino, Italy
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117
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Antonacci A, Lambreva MD, Margonelli A, Sobolev AP, Pastorelli S, Bertalan I, Johanningmeier U, Sobolev V, Samish I, Edelman M, Havurinne V, Tyystjärvi E, Giardi MT, Mattoo AK, Rea G. Photosystem-II D1 protein mutants of Chlamydomonas reinhardtii in relation to metabolic rewiring and remodelling of H-bond network at Q B site. Sci Rep 2018; 8:14745. [PMID: 30283151 PMCID: PMC6170454 DOI: 10.1038/s41598-018-33146-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 09/21/2018] [Indexed: 12/21/2022] Open
Abstract
Photosystem II (PSII) reaction centre D1 protein of oxygenic phototrophs is pivotal for sustaining photosynthesis. Also, it is targeted by herbicides and herbicide-resistant weeds harbour single amino acid substitutions in D1. Conservation of D1 primary structure is seminal in the photosynthetic performance in many diverse species. In this study, we analysed built-in and environmentally-induced (high temperature and high photon fluency – HT/HL) phenotypes of two D1 mutants of Chlamydomonas reinhardtii with Ala250Arg (A250R) and Ser264Lys (S264K) substitutions. Both mutations differentially affected efficiency of electron transport and oxygen production. In addition, targeted metabolomics revealed that the mutants undergo specific differences in primary and secondary metabolism, namely, amino acids, organic acids, pigments, NAD, xanthophylls and carotenes. Levels of lutein, β-carotene and zeaxanthin were in sync with their corresponding gene transcripts in response to HT/HL stress treatment in the parental (IL) and A250R strains. D1 structure analysis indicated that, among other effects, remodelling of H-bond network at the QB site might underpin the observed phenotypes. Thus, the D1 protein, in addition to being pivotal for efficient photosynthesis, may have a moonlighting role in rewiring of specific metabolic pathways, possibly involving retrograde signalling.
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Affiliation(s)
- Amina Antonacci
- Institute of Crystallography, National Research Council of Italy, Via Salaria Km 29,3 00015, Monterotondo Stazione, Rome, Italy
| | - Maya D Lambreva
- Institute of Crystallography, National Research Council of Italy, Via Salaria Km 29,3 00015, Monterotondo Stazione, Rome, Italy
| | - Andrea Margonelli
- Institute of Crystallography, National Research Council of Italy, Via Salaria Km 29,3 00015, Monterotondo Stazione, Rome, Italy
| | - Anatoly P Sobolev
- Institute of Chemical Methodologies, National Research Council of Italy, Via Salaria km 29,3 00015, Monterotondo Stazione, Rome, Italy
| | - Sandro Pastorelli
- Institute of Crystallography, National Research Council of Italy, Via Salaria Km 29,3 00015, Monterotondo Stazione, Rome, Italy.,Neotron S.p.a., Santa Maria di Mugnano, Modena, Italy
| | - Ivo Bertalan
- Martin-Luther-University, Plant Physiology Institute, Weinbergweg 10, D-06120, Halle Saale, Germany
| | - Udo Johanningmeier
- Martin-Luther-University, Plant Physiology Institute, Weinbergweg 10, D-06120, Halle Saale, Germany
| | - Vladimir Sobolev
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Ilan Samish
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel.,Amai Proteins Ltd., 2 Bergman St., Rehovot, Israel
| | - Marvin Edelman
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Vesa Havurinne
- Department of Biochemistry/Molecular Plant Biology, FI-20014, University of Turku, Turku, Finland
| | - Esa Tyystjärvi
- Department of Biochemistry/Molecular Plant Biology, FI-20014, University of Turku, Turku, Finland
| | - Maria T Giardi
- Institute of Crystallography, National Research Council of Italy, Via Salaria Km 29,3 00015, Monterotondo Stazione, Rome, Italy
| | - Autar K Mattoo
- The Henry A Wallace Beltsville Agricultural Research Centre, United States Department of Agriculture, Sustainable Agricultural Systems Laboratory, Beltsville, Maryland, 20705, USA.
| | - Giuseppina Rea
- Institute of Crystallography, National Research Council of Italy, Via Salaria Km 29,3 00015, Monterotondo Stazione, Rome, Italy.
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118
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Willamme R, Bogaert K, Remacle F, Remacle C. Surprisal analysis of the transcriptomic response of the green microalga Chlamydomonas to the addition of acetate during day/night cycles. Chem Phys 2018. [DOI: 10.1016/j.chemphys.2018.04.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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119
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Schindel HS, Piatek AA, Stewart CN, Lenaghan SC. The plastid genome as a chassis for synthetic biology-enabled metabolic engineering: players in gene expression. PLANT CELL REPORTS 2018; 37:1419-1429. [PMID: 30039465 DOI: 10.1007/s00299-018-2323-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 07/10/2018] [Indexed: 05/21/2023]
Abstract
Owing to its small size, prokaryotic-like molecular genetics, and potential for very high transgene expression, the plastid genome (plastome) is an attractive plant synthetic biology chassis for metabolic engineering. The plastome exists as a homogenous, compact, multicopy genome within multiple-specialized differentiated plastid compartments. Because of this multiplicity, transgenes can be highly expressed. For coordinated gene expression, it is the prokaryotic molecular genetics that is an especially attractive feature. Multiple genes in a metabolic pathway can be expressed in a series of operons, which are regulated at the transcriptional and translational levels with cross talk from the plant's nuclear genome. Key features of each regulatory level are reviewed, as well as some examples of plastome-enabled metabolic engineering. We also speculate about the transformative future of plastid-based synthetic biology to enable metabolic engineering in plants as well as the problems that must be solved before routine plastome-enabled synthetic circuits can be installed.
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Affiliation(s)
- Heidi S Schindel
- Department of Food Science, University of Tennessee, 2600 River Dr., Knoxville, TN, 37996-4561, USA
| | - Agnieszka A Piatek
- Department of Plant Sciences, University of Tennessee, 2431 Joe Johnson Dr., Knoxville, TN, 37996-4561, USA
| | - C Neal Stewart
- Department of Plant Sciences, University of Tennessee, 2431 Joe Johnson Dr., Knoxville, TN, 37996-4561, USA.
- Center for Agricultural Synthetic Biology, University of Tennessee Institute of Agriculture, Knoxville, TN, 37996, USA.
| | - Scott C Lenaghan
- Department of Food Science, University of Tennessee, 2600 River Dr., Knoxville, TN, 37996-4561, USA.
- Center for Agricultural Synthetic Biology, University of Tennessee Institute of Agriculture, Knoxville, TN, 37996, USA.
- Department of Mechanical, Aerospace, and Biomedical Engineering, University of Tennessee, Knoxville, TN, 37996, USA.
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120
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Global spectroscopic analysis to study the regulation of the photosynthetic proton motive force: A critical reappraisal. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:676-683. [DOI: 10.1016/j.bbabio.2018.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 06/03/2018] [Accepted: 07/02/2018] [Indexed: 01/11/2023]
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121
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Pieper K, Gundermann K, Dietzel L. Isolating and Incorporating Light-Harvesting Antennas from Diatom Cyclotella Meneghiniana in Liposomes with Thylakoid Lipids. J Vis Exp 2018. [PMID: 30222147 DOI: 10.3791/58017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The photosynthetic performance of plants, algae and diatoms strongly depends on the fast and efficient regulation of the light harvesting and energy transfer processes in the thylakoid membrane of chloroplasts. The light harvesting antenna of diatoms, the so called fucoxanthin chlorophyll a/c binding proteins (FCP), are required for the light absorption and efficient transfer to the photosynthetic reaction centers as well as for photo-protection from excessive light. The switch between these two functions is a long-standing matter of research. Many of these studies have been carried out with FCP in detergent micelles. For interaction studies, the detergents have been removed, which led to an unspecific aggregation of FCP complexes. In this approach, it is hard to discriminate between artifacts and physiologically relevant data. Hence, more valuable information about FCP and other membrane bound light harvesting complexes can be obtained by studying protein-protein interactions, energy transfer and other spectroscopic features if they are embedded in their native lipid environment. The main advantage is that liposomes have a defined size and a defined lipid/protein ratio by which the extent of FCP clustering is controlled. Further, changes in the pH and ion composition that regulate light harvesting in vivo can easily be simulated. In comparison to the thylakoid membrane, the liposomes are more homogenous and less complex, which makes it easier to obtain and understand spectroscopic data. The protocol describes the procedure of FCP isolation and purification, liposome preparation, and incorporation of FCP into liposomes with natural lipid composition. Results from a typical application are given and discussed.
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Affiliation(s)
| | | | - Lars Dietzel
- Institute for Molecular Biosciences, Goethe University;
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122
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Sivakaminathan S, Hankamer B, Wolf J, Yarnold J. High-throughput optimisation of light-driven microalgae biotechnologies. Sci Rep 2018; 8:11687. [PMID: 30076312 PMCID: PMC6076246 DOI: 10.1038/s41598-018-29954-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 07/19/2018] [Indexed: 12/18/2022] Open
Abstract
Microalgae biotechnologies are rapidly developing into new commercial settings. Several high value products already exist on the market, and systems development is focused on cost reduction to open up future economic opportunities for food, fuel and freshwater production. Light is a key environmental driver for photosynthesis and optimising light capture is therefore critical for low cost, high efficiency systems. Here a novel high-throughput screen that simulates fluctuating light regimes in mass cultures is presented. The data was used to model photosynthetic efficiency (PEµ, mol photon-1 m2) and chlorophyll fluorescence of two green algae, Chlamydomonas reinhardtii and Chlorella sp. Response surface methodology defined the effect of three key variables: density factor (Df, 'culture density'), cycle time (tc, 'mixing rate'), and maximum incident irradiance (Imax). Both species exhibited a large rise in PEµ with decreasing Imax and a minimal effect of tc (between 3-20 s). However, the optimal Df of 0.4 for Chlamydomonas and 0.8 for Chlorella suggested strong preferences for dilute and dense cultures respectively. Chlorella had a two-fold higher optimised PEµ than Chlamydomonas, despite its higher light sensitivity. These results demonstrate species-specific light preferences within the green algae clade. Our high-throughput screen enables rapid strain selection and process optimisation.
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Affiliation(s)
- Shwetha Sivakaminathan
- The University of Queensland, Institute for Molecular Bioscience, 306 Carmody Road, St Lucia, Australia
| | - Ben Hankamer
- The University of Queensland, Institute for Molecular Bioscience, 306 Carmody Road, St Lucia, Australia
| | - Juliane Wolf
- The University of Queensland, Institute for Molecular Bioscience, 306 Carmody Road, St Lucia, Australia.
| | - Jennifer Yarnold
- The University of Queensland, Institute for Molecular Bioscience, 306 Carmody Road, St Lucia, Australia.
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123
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Xue M, Long Y, Zhao Z, Huang G, Huang K, Zhang T, Jiang Y, Yuan Q, Pei X. Isolation and Characterization of a Green-Tissue Promoter from Common Wild Rice ( Oryza rufipogon Griff.). Int J Mol Sci 2018; 19:ijms19072009. [PMID: 29996483 PMCID: PMC6073244 DOI: 10.3390/ijms19072009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 06/28/2018] [Accepted: 07/05/2018] [Indexed: 01/10/2023] Open
Abstract
Promoters play a very important role in the initiation and regulation of gene transcription. Green-tissue promoter is of great significance to the development of genetically modified crops. Based on RNA-seq data and RT-PCR expression analysis, this study screened a gene, OrGSE (GREEN SPECIAL EXPRESS), which is expressed specifically in green tissues. The study also isolated the promoter of the OrGSE gene (OrGSEp), and predicted many cis-acting elements, such as the CAAT-Box and TATA-Box, and light-responding elements, including circadian, G-BOX and GT1 CONSENSUS. Histochemical analysis and quantification of GUS activity in transgenic Arabidopsis thaliana plants expressing GUS under the control of OrGSEp revealed that this promoter is not only green tissue-specific, but also light-inducible. The ability of a series of 5’-deletion fragments of OrGSEp to drive GUS expression in Arabidopsis was also evaluated. We found that the promoter region from −54 to −114 is critical for the promoter function, and the region from −374 to −114 may contain core cis-elements involved in light response. In transgenic rice expressing GUS under the control of OrGSEp, visualization and quantification of GUS activity showed that GUS was preferentially expressed in green tissues and not in endosperm. OrGSEp is a useful regulatory element for breeding pest-resistant crops.
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Affiliation(s)
- Mande Xue
- MOA Key Laboratory on Safety Assessment (Molecular) of Agri-GMO, Institute of Biotechnology, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Yan Long
- MOA Key Laboratory on Safety Assessment (Molecular) of Agri-GMO, Institute of Biotechnology, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Zhiqiang Zhao
- College of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China.
| | - Gege Huang
- College of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China.
| | - Ke Huang
- College of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China.
| | - Tianbao Zhang
- MOA Key Laboratory on Safety Assessment (Molecular) of Agri-GMO, Institute of Biotechnology, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Ying Jiang
- Experimental Center Basic Medical Teaching, Capital Medical University, Beijing 100069, China.
| | - Qianhua Yuan
- College of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China.
| | - Xinwu Pei
- MOA Key Laboratory on Safety Assessment (Molecular) of Agri-GMO, Institute of Biotechnology, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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124
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De-Luca R, Bernardi A, Meneghesso A, Morosinotto T, Bezzo F. Modelling the photosynthetic electron transport chain in Nannochloropsis gaditana via exploitation of absorbance data. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.06.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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125
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Rea G, Antonacci A, Lambreva MD, Mattoo AK. Features of cues and processes during chloroplast-mediated retrograde signaling in the alga Chlamydomonas. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2018; 272:193-206. [PMID: 29807591 DOI: 10.1016/j.plantsci.2018.04.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 04/04/2018] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
Retrograde signaling is an intracellular communication process defined by cues generated in chloroplast and mitochondria which traverse membranes to their destination in the nucleus in order to regulate nuclear gene expression and protein synthesis. The coding and decoding of such organellar message(s) involve gene medleys and metabolic components about which more is known in higher plants than the unicellular organisms such as algae. Chlamydomonas reinhardtii is an oxygenic microalgal model for genetic and physiological studies. It harbors a single chloroplast and is amenable for generating mutants. The focus of this review is on studies that delineate retrograde signaling in Chlamydomonas vis a vis higher plants. Thus, communication networks between chloroplast and nucleus involving photosynthesis- and ROS-generated signals, functional tetrapyrrole biosynthesis intermediates, and Ca2+-signaling that modulate nuclear gene expression in this alga are discussed. Conceptually, different signaling components converge to regulate either the same or functionally-overlapping gene products.
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Affiliation(s)
- Giuseppina Rea
- Institute of Crystallography, National Research Council of Italy, Via Salaria Km 29, 3 00015 Monterotondo Scalo, Rome, Italy
| | - Amina Antonacci
- Institute of Crystallography, National Research Council of Italy, Via Salaria Km 29, 3 00015 Monterotondo Scalo, Rome, Italy
| | - Maya D Lambreva
- Institute of Crystallography, National Research Council of Italy, Via Salaria Km 29, 3 00015 Monterotondo Scalo, Rome, Italy
| | - Autar K Mattoo
- The Henry A Wallace Agricultural Research Centre, U.S. Department of Agriculture, Sustainable Agricultural Systems Laboratory, Beltsville, MD 20705, USA.
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126
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van Rooijen R, Harbinson J, Aarts MGM. Photosynthetic response to increased irradiance correlates to variation in transcriptional response of lipid-remodeling and heat-shock genes. PLANT DIRECT 2018; 2:e00069. [PMID: 31245733 PMCID: PMC6508758 DOI: 10.1002/pld3.69] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 06/10/2018] [Accepted: 06/12/2018] [Indexed: 05/11/2023]
Abstract
Plants have evolved several mechanisms for sensing increased irradiance, involving signal perception by photoreceptors (cryptochromes), and subsequent biochemical (reactive oxygen species, ROS) and metabolic clues to transmit the signals. This results in the increased expression of heat-shock response genes and of the transcription factor LONG HYPOCOTYL 5 (HY5, mediated by the cryptochrome photoreceptor 1, CRY1). Here, we show the existence of another response pathway in Arabidopsis. This pathway evokes the SPX1-mediated expression activation of the transcription factor PHR1 and leads to the expression of several galactolipid biosynthesis genes. Gene expression analysis of accessions Col-0, Ga-0, and Ts-1, showed activated expression of the SPX1/PHR1-mediated gene expression activation pathway acting on galactolipids biosynthesis genes in both Ga-0 and Col-0, but not in Ts-1. The activation of the SPX1/PHR1-mediated response pathway can be associated with lower photosynthesis efficiency in Ts-1, compared to Col-0 and Ga-0. Besides the accession-associated activation of the SPX1/PHR1-mediated response pathway, comparing gene expression in the accessions showed stronger activation of several heat responsive genes in Ga-0, and the opposite in Ts-1, when compared to Col-0, in line with the differences in their efficiency of photosynthesis. We conclude that natural variation in activation of both heat responsive genes and of galactolipids biosynthesis genes contribute to the variation in photosynthesis efficiency in response to irradiance increase.
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Affiliation(s)
- Roxanne van Rooijen
- Laboratory of GeneticsWageningen University and ResearchWageningenThe Netherlands
- Horticulture and Product PhysiologyWageningen University and ResearchWageningenThe Netherlands
- Present address:
Cluster of Excellence on Plant ScienceHeinrich Heine UniversityDüsseldorfGermany
| | - Jeremy Harbinson
- Horticulture and Product PhysiologyWageningen University and ResearchWageningenThe Netherlands
| | - Mark G. M. Aarts
- Laboratory of GeneticsWageningen University and ResearchWageningenThe Netherlands
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127
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LOW PHOTOSYNTHETIC EFFICIENCY 1 is required for light-regulated photosystem II biogenesis in Arabidopsis. Proc Natl Acad Sci U S A 2018; 115:E6075-E6084. [PMID: 29891689 PMCID: PMC6042084 DOI: 10.1073/pnas.1807364115] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Photosystem II (PSII) reaction center protein D1 is encoded by chloroplast gene psbA and is crucial to the biogenesis and functional maintenance of PSII. D1 proteins are highly dynamic under varying light conditions and thus require efficient synthesis, but the mechanism remains poorly understood. We reported that Arabidopsis LPE1 directly binds to the 5′ UTR of psbA mRNA in a light-dependent manner through a redox-based mechanism and facilitates the association of HCF173 with psbA mRNA to regulate D1 translation. These findings fill a major gap in our understanding of the mechanism of light-regulated D1 synthesis in higher plants and imply that higher plants and primitive photosynthetic organisms share conserved mechanisms but use distinct regulators to regulate biogenesis of PSII subunits. Photosystem II (PSII), a multisubunit protein complex of the photosynthetic electron transport chain, functions as a water-plastoquinone oxidoreductase, which is vital to the initiation of photosynthesis and electron transport. Although the structure, composition, and function of PSII are well understood, the mechanism of PSII biogenesis remains largely elusive. Here, we identified a nuclear-encoded pentatricopeptide repeat (PPR) protein LOW PHOTOSYNTHETIC EFFICIENCY 1 (LPE1; encoded by At3g46610) in Arabidopsis, which plays a crucial role in PSII biogenesis. LPE1 is exclusively targeted to chloroplasts and directly binds to the 5′ UTR of psbA mRNA which encodes the PSII reaction center protein D1. The loss of LPE1 results in less efficient loading of ribosome on the psbA mRNA and great synthesis defects in D1 protein. We further found that LPE1 interacts with a known regulator of psbA mRNA translation HIGH CHLOROPHYLL FLUORESCENCE 173 (HCF173) and facilitates the association of HCF173 with psbA mRNA. More interestingly, our results indicate that LPE1 associates with psbA mRNA in a light-dependent manner through a redox-based mechanism. This study enhances our understanding of the mechanism of light-regulated D1 synthesis, providing important insight into PSII biogenesis and the functional maintenance of efficient photosynthesis in higher plants.
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128
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Wittkopp TM, Saroussi S, Yang W, Johnson X, Kim RG, Heinnickel ML, Russell JJ, Phuthong W, Dent RM, Broeckling CD, Peers G, Lohr M, Wollman FA, Niyogi KK, Grossman AR. GreenCut protein CPLD49 of Chlamydomonas reinhardtii associates with thylakoid membranes and is required for cytochrome b 6 f complex accumulation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 94:1023-1037. [PMID: 29602195 DOI: 10.1111/tpj.13915] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 02/23/2018] [Accepted: 03/06/2018] [Indexed: 06/08/2023]
Abstract
The GreenCut encompasses a suite of nucleus-encoded proteins with orthologs among green lineage organisms (plants, green algae), but that are absent or poorly conserved in non-photosynthetic/heterotrophic organisms. In Chlamydomonas reinhardtii, CPLD49 (Conserved in Plant Lineage and Diatoms49) is an uncharacterized GreenCut protein that is critical for maintaining normal photosynthetic function. We demonstrate that a cpld49 mutant has impaired photoautotrophic growth under high-light conditions. The mutant exhibits a nearly 90% reduction in the level of the cytochrome b6 f complex (Cytb6 f), which impacts linear and cyclic electron transport, but does not compromise the ability of the strain to perform state transitions. Furthermore, CPLD49 strongly associates with thylakoid membranes where it may be part of a membrane protein complex with another GreenCut protein, CPLD38; a mutant null for CPLD38 also impacts Cytb6 f complex accumulation. We investigated several potential functions of CPLD49, with some suggested by protein homology. Our findings are congruent with the hypothesis that CPLD38 and CPLD49 are part of a novel thylakoid membrane complex that primarily modulates accumulation, but also impacts the activity of the Cytb6 f complex. Based on motifs of CPLD49 and the activities of other CPLD49-like proteins, we suggest a role for this putative dehydrogenase in the synthesis of a lipophilic thylakoid membrane molecule or cofactor that influences the assembly and activity of Cytb6 f.
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Affiliation(s)
- Tyler M Wittkopp
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Shai Saroussi
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Wenqiang Yang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Xenie Johnson
- Laboratoire de Bioénergétique et Biotechnologie des Bactéries et Microalgues, CEA Cadarache, Saint Paul lez Durance, France
| | - Rick G Kim
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Mark L Heinnickel
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - James J Russell
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - Witchukorn Phuthong
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Rachel M Dent
- Department of Plant and Microbial Biology, Howard Hughes Medical Institute, University of California, Berkeley, CA, 94720-3102, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Corey D Broeckling
- Proteomics and Metabolomics Facility, Colorado State University, Fort Collins, CO, 80523, USA
| | - Graham Peers
- Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Martin Lohr
- Institut für Molekulare Physiologie - Pflanzenbiochemie, Johannes Gutenberg-Universität, 55099, Mainz, Germany
| | | | - Krishna K Niyogi
- Department of Plant and Microbial Biology, Howard Hughes Medical Institute, University of California, Berkeley, CA, 94720-3102, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Arthur R Grossman
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA
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Vergara C, Araujo KEC, Urquiaga S, Santa-Catarina C, Schultz N, da Silva Araújo E, de Carvalho Balieiro F, Xavier GR, Zilli JÉ. Dark Septate Endophytic Fungi Increase Green Manure- 15N Recovery Efficiency, N Contents, and Micronutrients in Rice Grains. FRONTIERS IN PLANT SCIENCE 2018; 9:613. [PMID: 29780402 PMCID: PMC5946629 DOI: 10.3389/fpls.2018.00613] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 04/18/2018] [Indexed: 06/02/2023]
Abstract
An understanding of the interaction between rice and dark septate endophytic (DSE) fungi, under green fertilization, may lead to sustainable agricultural practices. Nevertheless, this interaction is still poorly understood. Therefore, in this study, we aimed to evaluate the accumulation of macro- and micronutrients, dry matter, and protein and N recovery efficiency from Canavalia ensiformis (L.)-15N in rice inoculated with DSE fungi. An experiment under greenhouse conditions was conducted in a randomized complete block design comprising split-plots, with five replicates of rice plants potted in non-sterilized soil. Rice (Piauí variety) seedlings were inoculated with DSE fungi, A101 and A103, or left uninoculated (control) and transplanted into pots containing 12 kg of soil, which had previously been supplemented with dry, finely ground shoot biomass of C. ensiformis enriched with 2.15 atom % 15N. Two collections were performed in the experiment: one at 54 days after transplanting (DAT) and one at 130 DAT (at maturation). Growth indicators (at 54 DAT), grain yield, nutrient content, recovery efficiency, and the amount of N derived from C. ensiformis were quantified. At 54 DAT, the N content, chlorophyll content, and plant height of inoculated plants had increased significantly compared with the control, and these plants were more proficient in the use of N derived from C. ensiformis. At maturation, plants inoculated with A103 were distinguished by the recovery efficiency and amount of N derived from C. ensiformis and N content in the grain and shoot being equal to that in A101 inoculation and higher than that in the control, resulting in a higher accumulation of crude protein and dry matter in the full grain and panicle of DSE-rice interaction. In addition, Fe and Ni contents in the grains of rice inoculated with these fungi doubled with respect to the control, and in A103 inoculation, we observed Mn accumulation that was three times higher than in the other treatments. Our results suggest that the inoculation of rice with DSE fungi represents a strategy to improve green manure-N recovery, grain yield per plant, and grain quality in terms of micronutrients contents in cropping systems with a low N input.
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Affiliation(s)
- Carlos Vergara
- Departamento de Ciências do Solo, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | - Karla E. C. Araujo
- Departamento de Fitotecnia, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | | | - Claudete Santa-Catarina
- Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, Brazil
| | - Nivaldo Schultz
- Departamento de Ciências do Solo, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
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130
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Davis GA, Rutherford AW, Kramer DM. Hacking the thylakoid proton motive force for improved photosynthesis: modulating ion flux rates that control proton motive force partitioning into Δ ψ and ΔpH. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0381. [PMID: 28808100 DOI: 10.1098/rstb.2016.0381] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/31/2017] [Indexed: 11/12/2022] Open
Abstract
There is considerable interest in improving plant productivity by altering the dynamic responses of photosynthesis in tune with natural conditions. This is exemplified by the 'energy-dependent' form of non-photochemical quenching (qE), the formation and decay of which can be considerably slower than natural light fluctuations, limiting photochemical yield. In addition, we recently reported that rapidly fluctuating light can produce field recombination-induced photodamage (FRIP), where large spikes in electric field across the thylakoid membrane (Δψ) induce photosystem II recombination reactions that produce damaging singlet oxygen (1O2). Both qE and FRIP are directly linked to the thylakoid proton motive force (pmf), and in particular, the slow kinetics of partitioning pmf into its ΔpH and Δψ components. Using a series of computational simulations, we explored the possibility of 'hacking' pmf partitioning as a target for improving photosynthesis. Under a range of illumination conditions, increasing the rate of counter-ion fluxes across the thylakoid membrane should lead to more rapid dissipation of Δψ and formation of ΔpH. This would result in increased rates for the formation and decay of qE while resulting in a more rapid decline in the amplitudes of Δψ-spikes and decreasing 1O2 production. These results suggest that ion fluxes may be a viable target for plant breeding or engineering. However, these changes also induce transient, but substantial mismatches in the ATP : NADPH output ratio as well as in the osmotic balance between the lumen and stroma, either of which may explain why evolution has not already accelerated thylakoid ion fluxes. Overall, though the model is simplified, it recapitulates many of the responses seen in vivo, while spotlighting critical aspects of the complex interactions between pmf components and photosynthetic processes. By making the programme available, we hope to enable the community of photosynthesis researchers to further explore and test specific hypotheses.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'.
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Affiliation(s)
- Geoffry A Davis
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA.,Cell and Molecular Biology Graduate Program, Michigan State University, East Lansing, MI 48824, USA
| | | | - David M Kramer
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA .,Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
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131
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Berne N, Fabryova T, Istaz B, Cardol P, Bailleul B. The peculiar NPQ regulation in the stramenopile Phaeomonas sp. challenges the xanthophyll cycle dogma. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:491-500. [PMID: 29625087 DOI: 10.1016/j.bbabio.2018.03.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 03/15/2018] [Accepted: 03/28/2018] [Indexed: 10/17/2022]
Abstract
In changing light conditions, photosynthetic organisms develop different strategies to maintain a fine balance between light harvesting, photochemistry, and photoprotection. One of the most widespread photoprotective mechanisms consists in the dissipation of excess light energy in the form of heat in the photosystem II antenna, which participates to the Non Photochemical Quenching (NPQ) of chlorophyll fluorescence. It is tightly related to the reversible epoxidation of xanthophyll pigments, catalyzed by the two enzymes, the violaxanthin deepoxidase and the zeaxanthin epoxidase. In Phaeomonas sp. (Pinguiophyte, Stramenopiles), we show that the regulation of the heat dissipation process is different from that of the green lineage: the NPQ is strictly proportional to the amount of the xanthophyll pigment zeaxanthin and the xanthophyll cycle enzymes are differently regulated. The violaxanthin deepoxidase is already active in the dark, because of a low luminal pH, and the zeaxanthin epoxidase shows a maximal activity under moderate light conditions, being almost inactive in the dark and under high light. This light-dependency mirrors the one of NPQ: Phaeomonas sp. displays a large NPQ in the dark as well as under high light, which recovers under moderate light. Our results pinpoint zeaxanthin epoxidase activity as the prime regulator of NPQ in Phaeomonas sp. and therefore challenge the deepoxidase-regulated xanthophyll cycle dogma.
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Affiliation(s)
- N Berne
- Genetics and Physiology of microalgae, PhytoSYSTEMS/InBioS, Université de Liège, B-4000 Liège, Belgium
| | - T Fabryova
- Genetics and Physiology of microalgae, PhytoSYSTEMS/InBioS, Université de Liège, B-4000 Liège, Belgium
| | - B Istaz
- Genetics and Physiology of microalgae, PhytoSYSTEMS/InBioS, Université de Liège, B-4000 Liège, Belgium
| | - P Cardol
- Genetics and Physiology of microalgae, PhytoSYSTEMS/InBioS, Université de Liège, B-4000 Liège, Belgium.
| | - B Bailleul
- Genetics and Physiology of microalgae, PhytoSYSTEMS/InBioS, Université de Liège, B-4000 Liège, Belgium.
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132
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Demarsy E, Goldschmidt-Clermont M, Ulm R. Coping with 'Dark Sides of the Sun' through Photoreceptor Signaling. TRENDS IN PLANT SCIENCE 2018; 23:260-271. [PMID: 29233601 DOI: 10.1016/j.tplants.2017.11.007] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/16/2017] [Accepted: 11/17/2017] [Indexed: 05/19/2023]
Abstract
Plants grow in constantly changing environments, including highly variable light intensities. Sunlight provides the energy that drives photosynthesis and is thus of the utmost importance for plant growth and the generation of oxygen, which the majority of life on Earth depends on. However, exposure to either insufficient or excess levels of light can have detrimental effects and cause light stress. Whereas exposure to insufficient light limits photosynthetic activity, resulting in 'energy starvation', exposure to excess light can damage the photosynthetic apparatus. Furthermore, strong sunlight is associated with high levels of potentially damaging UV-B radiation. Different classes of photoreceptors play important roles in coping with the negative aspects of sunlight, for which specific mechanisms are emerging that are reviewed here.
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Affiliation(s)
- Emilie Demarsy
- Department of Botany and Plant Biology, Section of Biology, Faculty of Sciences, University of Geneva, Geneva, Switzerland
| | - Michel Goldschmidt-Clermont
- Department of Botany and Plant Biology, Section of Biology, Faculty of Sciences, University of Geneva, Geneva, Switzerland; Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva, Switzerland.
| | - Roman Ulm
- Department of Botany and Plant Biology, Section of Biology, Faculty of Sciences, University of Geneva, Geneva, Switzerland; Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva, Switzerland.
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133
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Chen Y, Zhou B, Li J, Tang H, Tang J, Yang Z. Formation and Change of Chloroplast-Located Plant Metabolites in Response to Light Conditions. Int J Mol Sci 2018; 19:E654. [PMID: 29495387 PMCID: PMC5877515 DOI: 10.3390/ijms19030654] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 02/22/2018] [Accepted: 02/23/2018] [Indexed: 11/16/2022] Open
Abstract
Photosynthesis is the central energy conversion process for plant metabolism and occurs within mature chloroplasts. Chloroplasts are also the site of various metabolic reactions involving amino acids, lipids, starch, and sulfur, as well as where the production of some hormones takes place. Light is one of the most important environmental factors, acting as an essential energy source for plants, but also as an external signal influencing their growth and development. Plants experience large fluctuations in the intensity and spectral quality of light, and many attempts have been made to improve or modify plant metabolites by treating them with different light qualities (artificial lighting) or intensities. In this review, we discuss how changes in light intensity and wavelength affect the formation of chloroplast-located metabolites in plants.
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Affiliation(s)
- Yiyong Chen
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, Guangzhou 510640, China.
| | - Bo Zhou
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, Guangzhou 510640, China.
| | - Jianlong Li
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, Guangzhou 510640, China.
| | - Hao Tang
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, Guangzhou 510640, China.
| | - Jinchi Tang
- Tea Research Institute, Guangdong Academy of Agricultural Sciences & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, Guangzhou 510640, China.
| | - Ziyin Yang
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
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134
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Gutu A, Chang F, O'Shea EK. Dynamical localization of a thylakoid membrane binding protein is required for acquisition of photosynthetic competency. Mol Microbiol 2018; 108:16-31. [PMID: 29357135 PMCID: PMC5910887 DOI: 10.1111/mmi.13912] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 01/02/2018] [Indexed: 11/29/2022]
Abstract
Vipp1 is highly conserved and essential for photosynthesis, but its function is unclear as it does not participate directly in light-dependent reactions. We analyzed Vipp1 localization in live cyanobacterial cells and show that Vipp1 is highly dynamic, continuously exchanging between a diffuse fraction that is uniformly distributed throughout the cell and a punctate fraction that is concentrated at high curvature regions of the thylakoid located at the cell periphery. Experimentally perturbing the spatial distribution of Vipp1 by relocalizing it to the nucleoid causes a severe growth defect during the transition from non-photosynthetic (dark) to photosynthetic (light) growth. However, the same perturbation of Vipp1 in dark alone or light alone growth conditions causes no growth or thylakoid morphology defects. We propose that the punctuated dynamics of Vipp1 at the cell periphery in regions of high thylakoid curvature enable acquisition of photosynthetic competency, perhaps by facilitating biogenesis of photosynthetic complexes involved in light-dependent reactions of photosynthesis.
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Affiliation(s)
- Andrian Gutu
- Howard Hughes Medical Institute, Harvard University Faculty of Arts and Sciences Center for Systems Biology, Cambridge, MA 02138, USA.,Department of Molecular and Cellular Biology, Harvard University Faculty of Arts and Sciences, Cambridge, MA 02138, USA.,Department of Chemistry and Chemical Biology, Harvard University Faculty of Arts and Sciences Center for Systems Biology, Cambridge, MA 02138, USA
| | - Frederick Chang
- Department of Molecular and Cellular Biology, Harvard University Faculty of Arts and Sciences, Cambridge, MA 02138, USA
| | - Erin K O'Shea
- Howard Hughes Medical Institute, Harvard University Faculty of Arts and Sciences Center for Systems Biology, Cambridge, MA 02138, USA.,Department of Molecular and Cellular Biology, Harvard University Faculty of Arts and Sciences, Cambridge, MA 02138, USA.,Department of Chemistry and Chemical Biology, Harvard University Faculty of Arts and Sciences Center for Systems Biology, Cambridge, MA 02138, USA
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135
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Da Q, Sun T, Wang M, Jin H, Li M, Feng D, Wang J, Wang HB, Liu B. M-type thioredoxins are involved in the xanthophyll cycle and proton motive force to alter NPQ under low-light conditions in Arabidopsis. PLANT CELL REPORTS 2018; 37:279-291. [PMID: 29080907 DOI: 10.1007/s00299-017-2229-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 10/18/2017] [Indexed: 06/07/2023]
Abstract
M-type thioredoxins are required to regulate zeaxanthin epoxidase activity and to maintain the steady-state level of the proton motive force, thereby influencing NPQ properties under low-light conditions in Arabidopsis. Non-photochemical quenching (NPQ) helps protect photosynthetic organisms from photooxidative damage via the non-radiative dissipation of energy as heat. Energy-dependent quenching (qE) is a major constituent of NPQ. However, the mechanism underlying the regulation of qE is not well understood. In this study, we demonstrate that the m-type thioredoxins TRX-m1, TRX-m2, and TRX-m4 (TRX-ms) interact with the xanthophyll cycle enzyme zeaxanthin epoxidase (ZE) and are required for maintaining the redox-dependent stabilization of ZE by regulating its intermolecular disulfide bridges. Reduced ZE activity and accumulated zeaxanthin levels were observed under TRX-ms deficiency. Furthermore, concurrent deficiency of TRX-ms resulted in a significant increase in proton motive force (pmf) and acidification of the thylakoid lumen under low irradiance, perhaps due to the significantly reduced ATP synthase activity under TRX-ms deficiency. The increased pmf, combined with acidification of the thylakoid lumen and the accumulation of zeaxanthin, ultimately contribute to the elevated stable qE in VIGS-TRX-m2m4/m1 plants under low-light conditions. Taken together, these results indicate that TRX-ms are involved in regulating NPQ-dependent photoprotection in Arabidopsis.
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Affiliation(s)
- Qingen Da
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275, Guangzhou, People's Republic of China
| | - Ting Sun
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275, Guangzhou, People's Republic of China
| | - Menglong Wang
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275, Guangzhou, People's Republic of China
| | - Honglei Jin
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275, Guangzhou, People's Republic of China
| | - Mengshu Li
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275, Guangzhou, People's Republic of China
| | - Dongru Feng
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275, Guangzhou, People's Republic of China
| | - Jinfa Wang
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275, Guangzhou, People's Republic of China
| | - Hong-Bin Wang
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275, Guangzhou, People's Republic of China
| | - Bing Liu
- State Key Laboratory of Biocontrol and Collaborative Innovation Center of Genetics and Development, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, 510275, Guangzhou, People's Republic of China.
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136
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Oh S, Strand DD, Kramer DM, Chen J, Montgomery BL. Transcriptome and phenotyping analyses support a role for chloroplast sigma factor 2 in red-light-dependent regulation of growth, stress, and photosynthesis. PLANT DIRECT 2018; 2:e00043. [PMID: 31245709 PMCID: PMC6508532 DOI: 10.1002/pld3.43] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 01/23/2018] [Accepted: 01/25/2018] [Indexed: 05/04/2023]
Abstract
Sigma factor (SIG) proteins contribute to promoter specificity of the plastid-encoded RNA polymerase during chloroplast genome transcription. All six members of the SIG family, that is, SIG1-SIG6, are nuclear-encoded proteins targeted to chloroplasts. Sigma factor 2 (SIG2) is a phytochrome-regulated protein important for stoichiometric control of the expression of plastid- and nuclear-encoded genes that impact plastid development and plant growth and development. Among SIG factors, SIG2 is required not only for transcription of chloroplast genes (i.e., anterograde signaling), but also impacts nuclear-encoded, photosynthesis-related, and light signaling-related genes (i.e., retrograde signaling) in response to plastid functional status. Although SIG2 is involved in photomorphogenesis in Arabidopsis, the molecular bases for its role in light signaling that impacts photomorphogenesis and aspects of photosynthesis have only recently begun to be investigated. Previously, we reported that SIG2 is necessary for phytochrome-mediated photomorphogenesis specifically under red (R) and far-red light, thereby suggesting a link between phytochromes and nuclear-encoded SIG2 in light signaling. To explore transcriptional roles of SIG2 in R-dependent growth and development, we performed RNA sequencing analysis to compare gene expression in sig2-2 mutant and Col-0 wild-type seedlings at two developmental stages (1- and 7-day). We identified a subset of misregulated genes involved in growth, hormonal cross talk, stress responses, and photosynthesis. To investigate the functional relevance of these gene expression analyses, we performed several comparative phenotyping tests. In these analyses, strong sig2 mutants showed insensitivity to bioactive GA 3, high intracellular levels of hydrogen peroxide (H2O2) indicative of a stress response, and specific defects in photosynthesis, including elevated levels of cyclic electron flow (CEF) and nonphotochemical quenching (NPQ). We demonstrated that SIG2 regulates a broader range of physiological responses at the molecular level than previously reported, with specific roles in red-light-mediated photomorphogenesis.
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Affiliation(s)
- Sookyung Oh
- Department of Energy – Plant Research LaboratoryMichigan State UniversityEast LansingMIUSA
| | - Deserah D. Strand
- Department of Energy – Plant Research LaboratoryMichigan State UniversityEast LansingMIUSA
- Present address:
Max‐Planck‐Institut für Molekulare PflanzenphysiologiePotsdam‐GolmGermany
| | - David M. Kramer
- Department of Energy – Plant Research LaboratoryMichigan State UniversityEast LansingMIUSA
- Department of Biochemistry and Molecular BiologyMichigan State UniversityEast LansingMIUSA
| | - Jin Chen
- UK Medical Center MN 150University of Kentucky College of MedicineLexingtonKYUSA
| | - Beronda L. Montgomery
- Department of Energy – Plant Research LaboratoryMichigan State UniversityEast LansingMIUSA
- Department of Biochemistry and Molecular BiologyMichigan State UniversityEast LansingMIUSA
- Department of Microbiology & Molecular GeneticsMichigan State UniversityEast LansingMIUSA
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137
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Cherepanov DA, Milanovsky GE, Petrova AA, Tikhonov AN, Semenov AY. Electron Transfer through the Acceptor Side of Photosystem I: Interaction with Exogenous Acceptors and Molecular Oxygen. BIOCHEMISTRY (MOSCOW) 2018; 82:1249-1268. [PMID: 29223152 DOI: 10.1134/s0006297917110037] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This review considers the state-of-the-art on mechanisms and alternative pathways of electron transfer in photosynthetic electron transport chains of chloroplasts and cyanobacteria. The mechanisms of electron transport control between photosystems (PS) I and II and the Calvin-Benson cycle are considered. The redistribution of electron fluxes between the noncyclic, cyclic, and pseudocyclic pathways plays an important role in the regulation of photosynthesis. Mathematical modeling of light-induced electron transport processes is considered. Particular attention is given to the electron transfer reactions on the acceptor side of PS I and to interactions of PS I with exogenous acceptors, including molecular oxygen. A kinetic model of PS I and its interaction with exogenous electron acceptors has been developed. This model is based on experimental kinetics of charge recombination in isolated PS I. Kinetic and thermodynamic parameters of the electron transfer reactions in PS I are scrutinized. The free energies of electron transfer between quinone acceptors A1A/A1B in the symmetric redox cofactor branches of PS I and iron-sulfur clusters FX, FA, and FB have been estimated. The second-order rate constants of electron transfer from PS I to external acceptors have been determined. The data suggest that byproduct formation of superoxide radical in PS I due to the reduction of molecular oxygen in the A1 site (Mehler reaction) can exceed 0.3% of the total electron flux in PS I.
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Affiliation(s)
- D A Cherepanov
- Lomonosov Moscow State University, Belozersky Institute of Physico-Chemical Biology, Moscow, 119992, Russia.
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138
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Abstract
This chapter presents an overview of structural properties of the cytochrome (Cyt) b 6 f complex and its functioning in chloroplasts. The Cyt b 6 f complex stands at the crossroad of photosynthetic electron transport pathways, providing connectivity between Photosystem (PSI) and Photosysten II (PSII) and pumping protons across the membrane into the thylakoid lumen. After a brief review of the chloroplast electron transport chain, the consideration is focused on the structural organization of the Cyt b 6 f complex and its interaction with plastoquinol (PQH2, reduced form of plastoquinone), a mediator of electron transfer from PSII to the Cyt b 6 f complex. The processes of PQH2 oxidation by the Cyt b 6 f complex have been considered within the framework of the Mitchell's Q-cycle. The overall rate of the intersystem electron transport is determined by PQH2 turnover at the quinone-binding site Qo of the Cyt b 6 f complex. The rate of PQH2 oxidation is controlled by the intrathylakoid pHin, which value determines the protonation/deprotonation events in the Qo-center. Two other regulatory mechanisms associated with the Cyt b 6 f complex are briefly overviewed: (i) redistribution of electron fluxes between alternative (linear and cyclic) pathways, and (ii) "state transitions" related to redistribution of solar energy between PSI and PSII.
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Hammel A, Zimmer D, Sommer F, Mühlhaus T, Schroda M. Absolute Quantification of Major Photosynthetic Protein Complexes in Chlamydomonas reinhardtii Using Quantification Concatamers (QconCATs). FRONTIERS IN PLANT SCIENCE 2018; 9:1265. [PMID: 30214453 PMCID: PMC6125352 DOI: 10.3389/fpls.2018.01265] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/10/2018] [Indexed: 05/03/2023]
Abstract
For modeling approaches in systems biology, knowledge of the absolute abundances of cellular proteins is essential. One way to gain this knowledge is the use of quantification concatamers (QconCATs), which are synthetic proteins consisting of proteotypic peptides derived from the target proteins to be quantified. The QconCAT protein is labeled with a heavy isotope upon expression in E. coli and known amounts of the purified protein are spiked into a whole cell protein extract. Upon tryptic digestion, labeled and unlabeled peptides are released from the QconCAT protein and the native proteins, respectively, and both are quantified by LC-MS/MS. The labeled Q-peptides then serve as standards for determining the absolute quantity of the native peptides/proteins. Here, we have applied the QconCAT approach to Chlamydomonas reinhardtii for the absolute quantification of the major proteins and protein complexes driving photosynthetic light reactions in the thylakoid membranes and carbon fixation in the pyrenoid. We found that with 25.2 attomol/cell the Rubisco large subunit makes up 6.6% of all proteins in a Chlamydomonas cell and with this exceeds the amount of the small subunit by a factor of 1.56. EPYC1, which links Rubisco to form the pyrenoid, is eight times less abundant than RBCS, and Rubisco activase is 32-times less abundant than RBCS. With 5.2 attomol/cell, photosystem II is the most abundant complex involved in the photosynthetic light reactions, followed by plastocyanin, photosystem I and the cytochrome b6/f complex, which range between 2.9 and 3.5 attomol/cell. The least abundant complex is the ATP synthase with 2 attomol/cell. While applying the QconCAT approach, we have been able to identify many potential pitfalls associated with this technique. We analyze and discuss these pitfalls in detail and provide an optimized workflow for future applications of this technique.
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140
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Céolin D, Kryzhevoi NV, Nicolas C, Pokapanich W, Choksakulporn S, Songsiriritthigul P, Saisopa T, Rattanachai Y, Utsumi Y, Palaudoux J, Öhrwall G, Rueff JP. Ultrafast Charge Transfer Processes Accompanying KLL Auger Decay in Aqueous KCl Solution. PHYSICAL REVIEW LETTERS 2017; 119:263003. [PMID: 29328710 DOI: 10.1103/physrevlett.119.263003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Indexed: 06/07/2023]
Abstract
X-ray photoelectron and KLL Auger spectra were measured for the K^{+} and Cl^{-} ions in aqueous KCl solution. While the XPS spectra of these ions have similar structures, both exhibiting only weak satellites near the main line, the Auger spectra differ dramatically. Contrary to the chloride case, a very strong extra peak was found in the Auger spectrum of K^{+} at the low kinetic energy side of the ^{1}D state. Using the equivalent core model and ab initio calculations this spectral feature was assigned to electron transfer processes from solvent water molecules to the solvated cation. The observed charge transfer processes are suggested to play an important role in charge redistribution following single and multiple core-hole creation in atoms and molecules placed into environment.
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Affiliation(s)
- D Céolin
- Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette Cedex, France
| | - N V Kryzhevoi
- Theoretical Chemistry, Institute of Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 229, 69120 Heidelberg, Germany
| | - Ch Nicolas
- Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette Cedex, France
| | - W Pokapanich
- Faculty of Science, Nakhon Phanom University, Nakhon Phanom 48000 Thailand
| | - S Choksakulporn
- Faculty of Science, Nakhon Phanom University, Nakhon Phanom 48000 Thailand
| | - P Songsiriritthigul
- NANOTEC-SUT Center of Excellence on Advanced Functional Nanomaterials and School of Physics, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
| | - T Saisopa
- NANOTEC-SUT Center of Excellence on Advanced Functional Nanomaterials and School of Physics, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
| | - Y Rattanachai
- Department of Applied Physics, Faculty of Sciences and Liberal Arts, Rajamangala University of Technology Isan, Nakhon Ratchasima 30000, Thailand
| | - Y Utsumi
- Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette Cedex, France
| | - J Palaudoux
- CNRS, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France
- Sorbonne Universités, UPMC Université Paris 06, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France
| | - G Öhrwall
- MAX IV Laboratory, Lund University, P.O. Box 118, SE-22100 Lund, Sweden
| | - J-P Rueff
- Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette Cedex, France
- CNRS, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France
- Sorbonne Universités, UPMC Université Paris 06, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France
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141
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Chloroplast signaling and quality control. Essays Biochem 2017; 62:13-20. [DOI: 10.1042/ebc20170048] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/06/2017] [Accepted: 10/13/2017] [Indexed: 11/17/2022]
Abstract
Although chloroplasts contain their own genetic system and are semi-autonomous cell organelles, plastid biogenesis and homeostasis are heavily dependent on the nucleo-cytosolic compartment. These two cellular compartments are closely co-ordinated through a complex signaling network comprising both anterograde and retrograde signaling chains. Developmental changes or any perturbation in the chloroplast system induced by a particular stress resulting from changes in environmental conditions such as excess light, elevated temperature, nutrient limitation, pathogen infection, give rise to specific signals. They migrate out of the chloroplast and are perceived by the nucleus where they elicit changes in expression of particular genes that allow for the maintenance of plastid homeostasis toward environmental cues. These genes mainly include those of photosynthesis-associated proteins, chaperones, proteases, nucleases and immune/defense proteins. Besides this transcriptional response, a chloroplast quality control system exists that is involved in the repair and turnover of damaged plastid proteins. This system degrades aggregated or damaged proteins and it can even remove entire chloroplasts when they have suffered heavy damage. This response comprises several processes such as plastid autophagy and ubiquitin–proteasome mediated proteolysis that occurs on the plastid envelope through the action of the ubiquitin–proteasome system.
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142
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Milić J, Zalibera M, Talaat D, Nomrowski J, Trapp N, Ruhlmann L, Boudon C, Wenger OS, Savitsky A, Lubitz W, Diederich F. Photoredox-Switchable Resorcin[4]arene Cavitands: Radical Control of Molecular Gripping Machinery via Hydrogen Bonding. Chemistry 2017; 24:1431-1440. [DOI: 10.1002/chem.201704788] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Indexed: 01/10/2023]
Affiliation(s)
- Jovana Milić
- Laboratory of Organic Chemistry; ETH Zurich; Vladimir-Prelog-Weg 3 8093 Zurich Switzerland
| | - Michal Zalibera
- Institute of Physical Chemistry and Chemical Physics; Slovak University of Technology; Radlinského 9 81237 Bratislava Slovakia
- Max Planck Institute for Chemical Energy Conversion; Stiftstrasse 34-36 45470 Mülheim an der Ruhr Germany
| | - Darius Talaat
- Laboratory of Organic Chemistry; ETH Zurich; Vladimir-Prelog-Weg 3 8093 Zurich Switzerland
| | - Julia Nomrowski
- Department of Chemistry; University of Basel; St. Johanns-Ring 19 4056 Basel Switzerland
| | - Nils Trapp
- Laboratory of Organic Chemistry; ETH Zurich; Vladimir-Prelog-Weg 3 8093 Zurich Switzerland
| | - Laurent Ruhlmann
- Laboratoire d'Électrochimie et Chimie Physique du Corps Solide, Institut de Chimie de Strasbourg; Université de Strasbourg; 4 rue Blaise Pascal, CS 90032 67081 Strasbourg France
| | - Corinne Boudon
- Laboratoire d'Électrochimie et Chimie Physique du Corps Solide, Institut de Chimie de Strasbourg; Université de Strasbourg; 4 rue Blaise Pascal, CS 90032 67081 Strasbourg France
| | - Oliver S. Wenger
- Department of Chemistry; University of Basel; St. Johanns-Ring 19 4056 Basel Switzerland
| | - Anton Savitsky
- Max Planck Institute for Chemical Energy Conversion; Stiftstrasse 34-36 45470 Mülheim an der Ruhr Germany
| | - Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion; Stiftstrasse 34-36 45470 Mülheim an der Ruhr Germany
| | - François Diederich
- Laboratory of Organic Chemistry; ETH Zurich; Vladimir-Prelog-Weg 3 8093 Zurich Switzerland
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143
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Mosebach L, Heilmann C, Mutoh R, Gäbelein P, Steinbeck J, Happe T, Ikegami T, Hanke G, Kurisu G, Hippler M. Association of Ferredoxin:NADP + oxidoreductase with the photosynthetic apparatus modulates electron transfer in Chlamydomonas reinhardtii. PHOTOSYNTHESIS RESEARCH 2017; 134:291-306. [PMID: 28593495 PMCID: PMC5683061 DOI: 10.1007/s11120-017-0408-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 05/26/2017] [Indexed: 05/22/2023]
Abstract
Ferredoxins (FDX) and the FDX:NADP+ oxidoreductase (FNR) represent a key junction of electron transport downstream of photosystem I (PSI). Dynamic recruitment of FNR to the thylakoid membrane has been considered as a potential mechanism to define the fate of photosynthetically derived electrons. In this study, we investigated the functional importance of the association of FNR with the photosynthetic apparatus in Chlamydomonas reinhardtii. In vitro assays based on NADP+ photoreduction measurements as well as NMR chemical shift perturbation analyses showed that FNR preferentially interacts with FDX1 compared to FDX2. Notably, binding of FNR to a PSI supercomplex further enhanced this preference for FDX1 over FDX2, suggesting that FNR is potentially capable of channelling electrons towards distinct routes. NADP+ photoreduction assays and immunoblotting revealed that the association of FNR with the thylakoid membrane including the PSI supercomplex is impaired in the absence of Proton Gradient Regulation 5 (PGR5) and/or Proton Gradient Regulation 5-Like photosynthetic phenotype 1 (PGRL1), implying that both proteins, directly or indirectly, contribute to the recruitment of FNR to the thylakoid membrane. As assessed via in vivo absorption spectroscopy and immunoblotting, PSI was the primary target of photodamage in response to high-light stress in the absence of PGR5 and/or PGRL1. Anoxia preserved the activity of PSI, pointing to enhanced electron donation to O2 as the source of the observed PSI inactivation and degradation. These findings establish another perspective on PGR5/PGRL1 knockout-related phenotypes and potentially interconnect FNR with the regulation of photosynthetic electron transport and PSI photoprotection in C. reinhardtii.
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Affiliation(s)
- Laura Mosebach
- Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, 48143, Münster, Germany
| | - Claudia Heilmann
- Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, 48143, Münster, Germany
| | - Risa Mutoh
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita-shi, Osaka, 565-0871, Japan
| | - Philipp Gäbelein
- Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, 48143, Münster, Germany
| | - Janina Steinbeck
- Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, 48143, Münster, Germany
| | - Thomas Happe
- Department of Plant Biochemistry, Ruhr-University Bochum, Universitätsstrasse 150, 44801, Bochum, Germany
| | - Takahisa Ikegami
- Structural Epigenetics Laboratory, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Guy Hanke
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Genji Kurisu
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita-shi, Osaka, 565-0871, Japan
| | - Michael Hippler
- Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 8, 48143, Münster, Germany.
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144
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Molinier J. Genome and Epigenome Surveillance Processes Underlying UV Exposure in Plants. Genes (Basel) 2017; 8:genes8110316. [PMID: 29120372 PMCID: PMC5704229 DOI: 10.3390/genes8110316] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 11/03/2017] [Accepted: 11/03/2017] [Indexed: 02/07/2023] Open
Abstract
Land plants and other photosynthetic organisms (algae, bacteria) use the beneficial effect of sunlight as a source of energy for the photosynthesis and as a major source of information from the environment. However, the ultraviolet component of sunlight also produces several types of damage, which can affect cellular and integrity, interfering with growth and development. In order to reduce the deleterious effects of UV, photosynthetic organisms combine physiological adaptation and several types of DNA repair pathways to avoid dramatic changes in the structure. Therefore, plants may have obtained an evolutionary benefit from combining genome and surveillance processes, to efficiently deal with the deleterious effects of UV radiation. This review will present the different mechanisms activated upon UV exposure that contribute to maintain genome and integrity.
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Affiliation(s)
- Jean Molinier
- Institut de Biologie Moléculaire des Plantes, UPR2357-CNRS, 12 rue du Général Zimmer, 67000 Strasbourg, France.
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145
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Lucker B, Schwarz E, Kuhlgert S, Ostendorf E, Kramer DM. Spectroanalysis in native gels (SING): rapid spectral analysis of pigmented thylakoid membrane complexes separated by CN-PAGE. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 92:744-756. [PMID: 28865165 DOI: 10.1111/tpj.13703] [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: 07/05/2017] [Revised: 08/22/2017] [Accepted: 08/29/2017] [Indexed: 06/07/2023]
Abstract
Photosynthetic organisms rapidly adjust the capture, transfer and utilization of light energy to optimize the efficiency of photosynthesis and avoid photodamage. These adjustments involve fine-tuning of expression levels and mutual interactions among electron/proton transfer components and their associated light-harvesting antenna. Detailed studies of these interactions and their dynamics have been hindered by the low throughput and resolution of currently available research tools, which involve laborious isolation, separation and characterization steps. To address these issues, we developed an approach that measured multiple spectroscopic properties of thylakoid preparations directly in native polyacrylamide gel electrophoresis gels, enabling unprecedented resolution of photosynthetic complexes, both in terms of the spectroscopic and functional details, as well as the ability to distinguish separate complexes and thus test their functional connections. As a demonstration, we explore the thylakoid membrane components of Chlamydomonas reinhardtii acclimated to high and low light, using a combination of room temperature absorption and 77K fluorescence emission to generate a multi-dimensional molecular and spectroscopic map of the photosynthetic apparatus. We show that low-light-acclimated cells accumulate a photosystem I-containing megacomplex that is absent in high-light-acclimated cells and contains distinct LhcII proteins that can be distinguished based on their spectral signatures.
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Affiliation(s)
- Ben Lucker
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - Eliezer Schwarz
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - Sebastian Kuhlgert
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - Elisabeth Ostendorf
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - David M Kramer
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
- DOE-Plant Research Laboratory, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
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146
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Kottke T, Oldemeyer S, Wenzel S, Zou Y, Mittag M. Cryptochrome photoreceptors in green algae: Unexpected versatility of mechanisms and functions. JOURNAL OF PLANT PHYSIOLOGY 2017; 217:4-14. [PMID: 28619534 DOI: 10.1016/j.jplph.2017.05.021] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 05/29/2017] [Accepted: 05/29/2017] [Indexed: 06/07/2023]
Abstract
Green algae have a highly complex and diverse set of cryptochrome photoreceptor candidates including members of the following subfamilies: plant, plant-like, animal-like, DASH and cryptochrome photolyase family 1 (CPF1). While some green algae encode most or all of them, others lack certain members. Here we present an overview about functional analyses of so far investigated cryptochrome photoreceptors from the green algae Chlamydomonas reinhardtii (plant and animal-like cryptochromes) and Ostreococcus tauri (CPF1) with regard to their biological significance and spectroscopic properties. Cryptochromes of both algae have been demonstrated recently to be involved to various extents in circadian clock regulation and in Chlamydomonas additionally in life cycle control. Moreover, CPF1 even performs light-driven DNA repair. The plant cryptochrome and CPF1 are UVA/blue light receptors, whereas the animal-like cryptochrome responds to almost the whole visible spectrum including red light. Accordingly, plant cryptochrome, animal-like cryptochrome and CPF1 differ fundamentally in their structural response to light as revealed by their visible and infrared spectroscopic signatures, and in the role of the flavin neutral radical acting as dark form or signaling state.
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Affiliation(s)
- Tilman Kottke
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany.
| | - Sabine Oldemeyer
- Physical and Biophysical Chemistry, Department of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Sandra Wenzel
- Institute of General Botany and Plant Physiology, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Yong Zou
- Institute of General Botany and Plant Physiology, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Maria Mittag
- Institute of General Botany and Plant Physiology, Friedrich Schiller University Jena, 07743 Jena, Germany.
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147
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A chloroplast thylakoid lumen protein is required for proper photosynthetic acclimation of plants under fluctuating light environments. Proc Natl Acad Sci U S A 2017; 114:E8110-E8117. [PMID: 28874535 DOI: 10.1073/pnas.1712206114] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Despite our increasingly sophisticated understanding of mechanisms ensuring efficient photosynthesis under laboratory-controlled light conditions, less is known about the regulation of photosynthesis under fluctuating light. This is important because-in nature-photosynthetic organisms experience rapid and extreme changes in sunlight, potentially causing deleterious effects on photosynthetic efficiency and productivity. Here we report that the chloroplast thylakoid lumenal protein MAINTENANCE OF PHOTOSYSTEM II UNDER HIGH LIGHT 2 (MPH2; encoded by At4g02530) is required for growth acclimation of Arabidopsis thaliana plants under controlled photoinhibitory light and fluctuating light environments. Evidence is presented that mph2 mutant light stress susceptibility results from a defect in photosystem II (PSII) repair, and our results are consistent with the hypothesis that MPH2 is involved in disassembling monomeric complexes during regeneration of dimeric functional PSII supercomplexes. Moreover, mph2-and previously characterized PSII repair-defective mutants-exhibited reduced growth under fluctuating light conditions, while PSII photoprotection-impaired mutants did not. These findings suggest that repair is not only required for PSII maintenance under static high-irradiance light conditions but is also a regulatory mechanism facilitating photosynthetic adaptation under fluctuating light environments. This work has implications for improvement of agricultural plant productivity through engineering PSII repair.
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148
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Mishanin VI, Trubitsin BV, Patsaeva SV, Ptushenko VV, Solovchenko AE, Tikhonov AN. Acclimation of shade-tolerant and light-resistant Tradescantia species to growth light: chlorophyll a fluorescence, electron transport, and xanthophyll content. PHOTOSYNTHESIS RESEARCH 2017; 133:87-102. [PMID: 28176042 DOI: 10.1007/s11120-017-0339-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 01/13/2017] [Indexed: 06/06/2023]
Abstract
In this study, we have compared the photosynthetic characteristics of two contrasting species of Tradescantia plants, T. fluminensis (shade-tolerant species), and T. sillamontana (light-resistant species), grown under the low light (LL, 50-125 µmol photons m-2 s-1) or high light (HL, 875-1000 µmol photons m-2 s-1) conditions during their entire growth period. For monitoring the functional state of photosynthetic apparatus (PSA), we measured chlorophyll (Chl) a emission fluorescence spectra and kinetics of light-induced changes in the heights of fluorescence peaks at 685 and 740 nm (F 685 and F 740). We also compared the light-induced oxidation of P700 and assayed the composition of carotenoids in Tradescantia leaves grown under the LL and HL conditions. The analyses of slow induction of Chl a fluorescence (SIF) uncovered different traits in the LL- and HL-grown plants of ecologically contrasting Tradescantia species, which may have potential ecophysiological significance with respect to their tolerance to HL stress. The fluorometry and EPR studies of induction events in chloroplasts in situ demonstrated that acclimation of both Tradescantia species to HL conditions promoted faster responses of their PSA as compared to LL-grown plants. Acclimation of both species to HL also caused marked changes in the leaf anatomy and carotenoid composition (an increase in Violaxanthin + Antheraxantin + Zeaxanthin and Lutein pools), suggesting enhanced photoprotective capacity of the carotenoids in the plants grown in nature under high irradiance. Collectively, the results of the present work suggest that the mechanisms of long-term PSA photoprotection in Tradescantia are based predominantly on the light-induced remodeling of pigment-protein complexes in chloroplasts.
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Affiliation(s)
- Vladimir I Mishanin
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Boris V Trubitsin
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Svetlana V Patsaeva
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Vasily V Ptushenko
- A.N. Belozersky Institute of Physical-Chemical Biology, M.V. Lomonosov Moscow State University, Moscow, 119234, Russia
- N.M. Emanuel Institute of Biochemical Physics, Moscow, 119334, Russia
| | - Alexei E Solovchenko
- Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Alexander N Tikhonov
- Faculty of Physics, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia.
- N.M. Emanuel Institute of Biochemical Physics, Moscow, 119334, Russia.
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149
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Tikhonov AN, Vershubskii AV. Connectivity between electron transport complexes and modulation of photosystem II activity in chloroplasts. PHOTOSYNTHESIS RESEARCH 2017; 133:103-114. [PMID: 28275891 DOI: 10.1007/s11120-017-0349-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 02/02/2017] [Indexed: 06/06/2023]
Abstract
In chloroplasts, photosynthetic electron transport complexes interact with each other via the mobile electron carriers (plastoquinone and plastocyanin) which are in surplus amounts with respect to photosystem I and photosystem II (PSI and PSII), and the cytochrome b 6 f complex. In this work, we analyze experimental data on the light-induced redox transients of photoreaction center P700 in chloroplasts within the framework of our mathematical model. This analysis suggests that during the action of a strong actinic light, even significant attenuation of PSII [for instance, in the result of inhibition of a part of PSII complexes by DCMU or due to non-photochemical quenching (NPQ)] will not cause drastic shortage of electron flow through PSI. This can be explained by "electronic" and/or "excitonic" connectivity between different PSII units. At strong AL, the overall flux of electrons between PSII and PSI will maintain at a high level even with the attenuation of PSII activity, provided the rate-limiting step of electron transfer is beyond the stage of PQH2 formation. Results of our study are briefly discussed in the context of NPQ-dependent mechanism of chloroplast protection against light stress.
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150
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Ahmad RA, Dietzel L. Relaxation of cellular K + gradients by valinomycin induces diatoxanthin accumulation in Cyclotella meneghiniana cells and alters FCPa fluorescence yield in vitro. PHYSIOLOGIA PLANTARUM 2017; 161:171-180. [PMID: 28664565 DOI: 10.1111/ppl.12599] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 06/14/2017] [Accepted: 06/23/2017] [Indexed: 06/07/2023]
Abstract
Regulation of photosynthetic light harvesting involves all major thylakoid membrane complexes. One important factor is the proton motive force (pmf) driving ATP production. Its proton gradient (ΔpH) component regulates the high energy quenching. Potassium ions largely contribute to the formation of the electric field (ΔΨ). ΔΨ and ΔpH partially compensate each other to form pmf. Whilst in plants considerable progress has been made in analyzing the interplay of H+ and K+ gradients, in diatoms knowledge in this field is still scarce. We relaxed cellular K+ gradients by valinomycin in Cyclotella meneghiniana. We observed a slow decrease of PSII maximum quantum yield in the dark upon valinomycin addition correlating with diatoxanthin accumulation which we attribute to the breakdown of organellar K+ gradients (either plastid or mitochondria) which might compensate for the loss of the K+ gradient by adjustment of the thylakoid pH in a secondary step. This response is reversible when ΔpH is relaxed. Similarly, we found higher non-photochemical quenching (NPQ) caused by higher DT accumulation in the steady state in valinomycin-treated cells. In vitro fucoxanthin chlorophyll a (FCPa) antenna complexes in liposomes with natural lipid composition showed a decrease in fluorescence yield if a K+ gradient is built up. The effect reversed by relaxing the gradient. We interpret these fluorescence changes with surface charge dynamics and FCPa organization in the membrane rather than a direct influence of K+ gradients on FCPa complexes. Both experiments reveal that K+ gradients might contribute to fine tuning of light harvesting capacity in relation to pmf in diatoms.
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Affiliation(s)
- Rana A Ahmad
- Institute of Molecular Biosciences, Department of Plant Cell Physiology, Goethe University Frankfurt, Frankfurt 60438, Germany
| | - Lars Dietzel
- Institute of Molecular Biosciences, Department of Plant Cell Physiology, Goethe University Frankfurt, Frankfurt 60438, Germany
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