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Das S, Gevaert F, Ouddane B, Duong G, Souissi S. Single toxicity of arsenic and combined trace metal exposure to a microalga of ecological and commercial interest: Diacronema lutheri. CHEMOSPHERE 2022; 291:132949. [PMID: 34798102 DOI: 10.1016/j.chemosphere.2021.132949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/14/2021] [Accepted: 11/15/2021] [Indexed: 06/13/2023]
Abstract
Eco-toxicological assays with species of economic interest such as Diacronema lutheri are essential for industries that produce aquaculture feed, natural food additives and also in drug developing industries. Our study involved the exposure of a single and combined toxicity of arsenic (As V) to D. lutheri for the entire algal growth phase and highlighted that a combined exposure of As V with other essential (Copper, Cu; Nickel, Ni) and non-essential (Cadmium, Cd; Lead, Pb) trace metals reduced significantly the cell number, chlorophyll a content, and also significantly increased the de-epoxidation ratio (DR) as a stress response when compared to the single toxicity of As V. Arsenic, as one of the ubiquitous trace metal and an active industrial effluent is reported to have an increased bio-concentration factor when in mixture with other trace metals in this study. In the combined exposure, the concentration of total As bio-accumulated by D. lutheri was higher than in the single exposure. Hence, polluted areas with the prevalence of multiple contaminants along with the highly toxic trace metals like As can impose a greater risk to the exposed organisms that may get further bio-magnified in the food chain. Our study highlights the consequences and the response of D. lutheri in terms of contamination from single and multiple trace metals in order to obtain a safer biomass production for the growing need of natural derivatives.
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Affiliation(s)
- Shagnika Das
- Univ. Lille, CNRS, Univ. Littoral Côte D'Opale, IRD, UMR 8187 - LOG - Laboratoire D'Océanologie et de Géosciences, Station Marine de Wimereux, F-59000, Lille, France; Univ. Lille, CNRS, UMR 8516 - LASIRE - Equipe Physico-chimie de L'Environnement, Bâtiment C8, F-59000, Lille, France
| | - François Gevaert
- Univ. Lille, CNRS, Univ. Littoral Côte D'Opale, IRD, UMR 8187 - LOG - Laboratoire D'Océanologie et de Géosciences, Station Marine de Wimereux, F-59000, Lille, France
| | - Baghdad Ouddane
- Univ. Lille, CNRS, UMR 8516 - LASIRE - Equipe Physico-chimie de L'Environnement, Bâtiment C8, F-59000, Lille, France
| | - Gwendoline Duong
- Univ. Lille, CNRS, Univ. Littoral Côte D'Opale, IRD, UMR 8187 - LOG - Laboratoire D'Océanologie et de Géosciences, Station Marine de Wimereux, F-59000, Lille, France
| | - Sami Souissi
- Univ. Lille, CNRS, Univ. Littoral Côte D'Opale, IRD, UMR 8187 - LOG - Laboratoire D'Océanologie et de Géosciences, Station Marine de Wimereux, F-59000, Lille, France.
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Adams Iii WW, Stewart JJ, Polutchko SK, Demmig-Adams B. Foliar sieve elements: Nexus of the leaf. JOURNAL OF PLANT PHYSIOLOGY 2022; 269:153601. [PMID: 34953412 DOI: 10.1016/j.jplph.2021.153601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/30/2021] [Accepted: 12/15/2021] [Indexed: 06/14/2023]
Abstract
In this review, a central position of foliar sieve elements in linking leaf structure and function is explored. Results from studies involving plants grown under, and acclimated to, different growth regimes are used to identify significant, linear relationships between features of minor vein sieve elements and those of 1) leaf photosynthetic capacity that drives sugar synthesis, 2) overall leaf structure that serves as the platform for sugar production, 3) phloem components that facilitate the loading of sugars (companion & phloem parenchyma cells), and 4) the tracheary elements that import water to support photosynthesis (and stomatal opening) as well as mass flow of sugars out of the leaf. Despite comprising only a small fraction of physical space within the leaf, sieve elements represent a hub through which multiple functions of the leaf intersect. As the conduits for export of energy-rich carbohydrates, essential mineral nutrients, and information carriers, sieve elements play a central role in fueling and orchestrating development and function of the plant as well as, by extension, of natural and human communities that depend on plants as producers and partners in the global carbon cycle.
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Affiliation(s)
- William W Adams Iii
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA.
| | - Jared J Stewart
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA.
| | - Stephanie K Polutchko
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA.
| | - Barbara Demmig-Adams
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA.
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3
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Sipka G, Magyar M, Mezzetti A, Akhtar P, Zhu Q, Xiao Y, Han G, Santabarbara S, Shen JR, Lambrev PH, Garab G. Light-adapted charge-separated state of photosystem II: structural and functional dynamics of the closed reaction center. THE PLANT CELL 2021; 33:1286-1302. [PMID: 33793891 PMCID: PMC8225241 DOI: 10.1093/plcell/koab008] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 12/13/2020] [Indexed: 05/04/2023]
Abstract
Photosystem II (PSII) uses solar energy to oxidize water and delivers electrons for life on Earth. The photochemical reaction center of PSII is known to possess two stationary states. In the open state (PSIIO), the absorption of a single photon triggers electron-transfer steps, which convert PSII into the charge-separated closed state (PSIIC). Here, by using steady-state and time-resolved spectroscopic techniques on Spinacia oleracea and Thermosynechococcus vulcanus preparations, we show that additional illumination gradually transforms PSIIC into a light-adapted charge-separated state (PSIIL). The PSIIC-to-PSIIL transition, observed at all temperatures between 80 and 308 K, is responsible for a large part of the variable chlorophyll-a fluorescence (Fv) and is associated with subtle, dark-reversible reorganizations in the core complexes, protein conformational changes at noncryogenic temperatures, and marked variations in the rates of photochemical and photophysical reactions. The build-up of PSIIL requires a series of light-induced events generating rapidly recombining primary radical pairs, spaced by sufficient waiting times between these events-pointing to the roles of local electric-field transients and dielectric relaxation processes. We show that the maximum fluorescence level, Fm, is associated with PSIIL rather than with PSIIC, and thus the Fv/Fm parameter cannot be equated with the quantum efficiency of PSII photochemistry. Our findings resolve the controversies and explain the peculiar features of chlorophyll-a fluorescence kinetics, a tool to monitor the functional activity and the structural-functional plasticity of PSII in different wild-types and mutant organisms and under stress conditions.
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Affiliation(s)
- G�bor Sipka
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
| | - Melinda Magyar
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
| | - Alberto Mezzetti
- Universit� Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC) 91191 Gif-sur-Yvette, France
- Laboratoire de R�activit� de Surface UMR 7197, Sorbonne University, Paris, France
| | - Parveen Akhtar
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
- ELI-ALPS, ELI-HU Nonprofit Ltd., Szeged, Hungary
| | - Qingjun Zhu
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Yanan Xiao
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Guangye Han
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Stefano Santabarbara
- Photosynthetic Research Unit, Institute of Biophysics, National Research Council of Italy, Milano, Italy
| | - Jian-Ren Shen
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- Research Institute for Interdisciplinary Science, and Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | - Petar H Lambrev
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
- Author for correspondence: (G.G.), (P.H.L.)
| | - Győző Garab
- Institute of Plant Biology, Biological Research Centre, Szeged, Hungary
- Faculty of Science, University of Ostrava, Ostrava, Czech Republic
- Author for correspondence: (G.G.), (P.H.L.)
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Pivato M, Perozeni F, Licausi F, Cazzaniga S, Ballottari M. Heterologous expression of cyanobacterial Orange Carotenoid Protein (OCP2) as a soluble carrier of ketocarotenoids in Chlamydomonas reinhardtii. ALGAL RES 2021; 55:102255. [PMID: 33777686 PMCID: PMC7610433 DOI: 10.1016/j.algal.2021.102255] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Photosynthetic organisms evolved different mechanisms to protect themselves from high irradiances and photodamage. In cyanobacteria, the photoactive Orange Carotenoid-binding Protein (OCP) acts both as a light sensor and quencher of excitation energy. It binds keto-carotenoids and, when photoactivated, interacts with phyco-bilisomes, thermally dissipating the excitation energy absorbed by the latter, and acting as efficient singlet oxygen quencher. Here, we report the heterologous expression of an OCP2 protein from the thermophilic cyanobacterium Fischerella thermalis (FtOCP2) in the model organism for green algae, Chlamydomonas reinhardtii. Robust expression of FtOCP2 was obtained through a synthetic redesigning strategy for optimized expression of the transgene. FtOCP2 expression was achieved both in UV-mediated mutant 4 strain, previously selected for efficient transgene expression, and in a background strain previously engineered for constitutive expression of an endogenous β-carotene ketolase, normally poorly expressed in this species, resulting into astaxanthin and other ketocarotenoids accumulation. Recombinant FtOCP2 was successfully localized into the chloroplast. Upon purification it was possible to demonstrate the formation of holoproteins with different xanthophylls and keto-carotenoids bound, including astaxanthin. Moreover, isolated ketocarotenoid-binding FtOCP2 holoproteins conserved their photoconversion properties. Carotenoids bound to FtOCP2 were thus maintained in solution even in absence of organic solvent. The synthetic biology approach herein reported could thus be considered as a novel tool for improving the solubility of ketocarotenoids produced in green algae, by binding to water-soluble carotenoids binding proteins.
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Xie Y, Chen L, Sun T, Zhang W. Deciphering and engineering high-light tolerant cyanobacteria for efficient photosynthetic cell factories. Chin J Chem Eng 2021. [DOI: 10.1016/j.cjche.2020.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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6
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Yang C, Li R, Zhang KAI, Lin W, Landfester K, Wang X. Heterogeneous photoredox flow chemistry for the scalable organosynthesis of fine chemicals. Nat Commun 2020; 11:1239. [PMID: 32144271 PMCID: PMC7060272 DOI: 10.1038/s41467-020-14983-w] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Accepted: 02/11/2020] [Indexed: 11/09/2022] Open
Abstract
Large-scale photochemical synthesis of high value chemicals under mild conditions is an ideal method of green chemical production. However, a scalable photocatalytic process has been barely reported due to the costly preparation, low stability of photosensitizers and critical reaction conditions required for classical photocatalysts. Here, we report the merging of flow chemistry with heterogeneous photoredox catalysis for the facile production of high value compounds in a continuous flow reactor with visible light at room temperature in air. In the flow reactor system, polymeric carbon nitrides, which are cheap, sustainable and stable heterogeneous photocatalysts, are immobilized onto glass beads and fibers, demonstrating a highly flexible construction possibility for devices of the photocatalytic materials. As an example of the production of high value chemicals, important chemical structures such as cyclobutanes, which are basic building blocks for many pharmaceutical compounds, like magnosalin, are synthesized in flow with high catalytic efficiency and stability.
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Affiliation(s)
- Can Yang
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350002, P. R. China
| | - Run Li
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Kai A I Zhang
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.
| | - Wei Lin
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350002, P. R. China
| | - Katharina Landfester
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Xinchen Wang
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350002, P. R. China.
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Castellanos-Soriano J, Herrera-Luna JC, Díaz Díaz D, Jiménez MC, Pérez-Ruiz R. Recent applications of biphotonic processes in organic synthesis. Org Chem Front 2020. [DOI: 10.1039/d0qo00466a] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Organic synthesis mediated by biphotonic processes has gained great momentum in the last five years. Herein, an overview of the existing examples is reported.
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Affiliation(s)
| | | | - David Díaz Díaz
- Institut für Organische Chemie
- Universität Regensburg
- 93053 Regensburg
- Germany
- Departamento de Química Orgánica
| | - M. Consuelo Jiménez
- Departamento de Química
- Universitat Politècnica de València (UPV)
- Valencia
- Spain
| | - Raúl Pérez-Ruiz
- Departamento de Química
- Universitat Politècnica de València (UPV)
- Valencia
- Spain
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8
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Less photoprotection can be good in some genetic and environmental contexts. Biochem J 2019; 476:2017-2029. [PMID: 31320389 DOI: 10.1042/bcj20190328] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 06/26/2019] [Accepted: 07/01/2019] [Indexed: 12/22/2022]
Abstract
Antioxidant systems modulate oxidant-based signaling networks and excessive removal of oxidants can prevent beneficial acclimation responses. Evidence from mutant, transgenic, and locally adapted natural plant systems is used to interpret differences in the capacity for antioxidation and formulate hypotheses for future inquiry. We focus on the first line of chloroplast antioxidant defense, pre-emptive thermal dissipation of excess absorbed light (monitored as nonphotochemical fluorescence quenching, NPQ) as well as on tocopherol-based antioxidation. Findings from NPQ-deficient and tocopherol-deficient mutants that exhibited enhanced biomass production and/or enhanced foliar water-transport capacity are reviewed and discussed in the context of the impact of lower levels of antioxidation on plant performance in hot/dry conditions, under cool temperature, and in the presence of biotic stress. The complexity of cellular redox-signaling networks is related to the complexity of environmental and endogenous inputs as well as to the need for intensified training and collaboration in the study of plant-environment interactions across biological sub-disciplines.
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Znad H, Al Ketife AMD, Judd S. Enhancement of CO 2 biofixation and lipid production by Chlorella vulgaris using coloured polypropylene film. ENVIRONMENTAL TECHNOLOGY 2019; 40:2093-2099. [PMID: 29405086 DOI: 10.1080/09593330.2018.1437778] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 02/03/2018] [Indexed: 06/07/2023]
Abstract
Chlorella vulgaris was cultivated with light at different wavelengths (λmax) and irradiation intensities (I) by applying a coloured tape (CT) as a simple, inexpensive light filter. C. vulgaris was cultivated in a standard medium using blue (CTB), green (CTG), red (CTR), yellow (CTY) and white (CTW) CT to filter the light, as well the unfiltered light (U). The influence of λmax and I on specific growth rate (μ), nutrient removal efficiency (% RE of total nitrogen, TN, and phosphorus, TP), CO2 fixation rate (RC) and lipid productivity (Plipid) were evaluated. The highest biomass concentration Xmax of 2.26 g L-1 was measured for CTW with corresponding μ, TN and TP RE, RC and Plipid values of 0.95 d-1, 92% and 100%, 0.67 g L-1 d-1 and 83.6 mg L-1 d-1, respectively. The normalised μ and Plipid for U were significantly lower than in CTW of 33-50% and 75%, respectively. The corresponding non-normalised parameter values for CTB were significantly lower at 0.45 d-1, 0.18 g L-1, 15% and 37%, 0.03 g L-1 d-1 and 1.2 mg L-1 d-1. Results suggest a significant impact of I and λmax, with up to a 50% increase in growth and nutrient RE from optimising these parameters.
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Affiliation(s)
- Hussein Znad
- a Department of Chemical Engineering, Curtin University , Perth , Australia
| | | | - Simon Judd
- b Gas Processing Center, Qatar University , Doha , Qatar
- c Cranfield Water Science Institute, Cranfield University , Cranfield , UK
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Hollis L, Ivanov AG, Hüner NPA. Chlorella vulgaris integrates photoperiod and chloroplast redox signals in response to growth at high light. PLANTA 2019; 249:1189-1205. [PMID: 30603788 DOI: 10.1007/s00425-018-03070-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 12/17/2018] [Indexed: 05/28/2023]
Abstract
Photoacclimation to variable light and photoperiod regimes in C. vulgaris represents a complex interplay between "biogenic" phytochrome-mediated sensing and "operational" redox sensing signaling pathways. Chlorella vulgaris Beijerinck UTEX 265 exhibits a yellow-green phenotype when grown under high light (HL) in contrast to a dark green phenotype when grown at low light (LL). The redox state of the photosynthetic electron transport chain (PETC) as estimated by excitation pressure has been proposed to govern this phenotypic response. We hypothesized that if the redox state of the PETC was the sole regulator of the HL phenotype, C. vulgaris should photoacclimate in response to the steady-state excitation pressure during the light period regardless of the length of the photoperiod. As expected, LL-grown cells exhibited a dark green phenotype, low excitation pressure (1 - qP = 0.22 ± 0.02), high chlorophyll (Chl) content (375 ± 77 fg Chl/cell), low Chl a/b ratio (2.97 ± 0.18) as well as high photosynthetic efficiency and photosynthetic capacity regardless of the photoperiod. In contrast, C. vulgaris grown under continuous HL developed a yellow-green phenotype characterized by high excitation pressure (1 - qP = 0.68 ± 0.01), a relatively low Chl content (180 ± 53 fg Chl/cell), high Chl a/b ratio (6.36 ± 0.54) with concomitantly reduced light-harvesting polypeptide abundance, as well as low photosynthetic capacity and efficiency measured on a per cell basis. Although cells grown under HL and an 18 h photoperiod developed a typical yellow-green phenotype, cells grown at HL but a 12 h photoperiod exhibited a dark green phenotype comparable to LL-grown cells despite exhibiting growth under high excitation pressure (1 - qP = 0.80 ± 0.04). The apparent uncoupling of excitation pressure and phenotype in HL-grown cells and a 12 h photoperiod indicates that chloroplast redox status cannot be the sole regulator of photoacclimation in C. vulgaris. We conclude that photoacclimation in C. vulgaris to HL is dependent upon growth history and reflects a complex interaction of endogenous systems that sense changes in photoperiod as well as photosynthetic redox balance.
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Affiliation(s)
- Lauren Hollis
- Department of Biology and The Biotron Centre for Experimental Climate Change Research, University of Western Ontario, London, N6A 5B7, Canada
| | - Alexander G Ivanov
- Department of Biology and The Biotron Centre for Experimental Climate Change Research, University of Western Ontario, London, N6A 5B7, Canada
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, 1113, Sofia, Bulgaria
| | - Norman P A Hüner
- Department of Biology and The Biotron Centre for Experimental Climate Change Research, University of Western Ontario, London, N6A 5B7, Canada.
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K.V. A, K. A, A.P. S, C.C. H. Energy efficient technology for enhanced growth and lipid production in Chlamydomonas reinhardtii through additional reflector coated LED photo-bioreactor. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.01.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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12
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Zhang Y, Wu H, Sun M, Peng Q, Li A. Photosynthetic physiological performance and proteomic profiling of the oleaginous algae Scenedesmus acuminatus reveal the mechanism of lipid accumulation under low and high nitrogen supplies. PHOTOSYNTHESIS RESEARCH 2018; 138:73-102. [PMID: 30039359 DOI: 10.1007/s11120-018-0549-1] [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: 12/26/2017] [Accepted: 06/25/2018] [Indexed: 06/08/2023]
Abstract
In this study, we presented cellular morphological changes, time-resolved biochemical composition, photosynthetic performance and proteomic profiling to capture the photosynthetic physiological response of Scenedesmus acuminatus under low nitrogen (3.6 mM NaNO3, N-) and high nitrogen supplies (18.0 mM NaNO3, N+). S. acuminatus cells showed extensive lipid accumulation (53.7% of dry weight) and were enriched in long-chain fatty acids (C16 & C18) under low nitrogen supply. The activity of PSII and photosynthetic rate decreases, whereas non-photochemical quenching and dark respiration rates were increased in the N- group. In addition, the results indicated a redistribution of light excitation energy between PSII and PSI in S. acuminatus exists before lipid accumulation. The iTRAQ results showed that, under high nitrogen supply, protein abundance of the chlorophyll biosynthesis, the Calvin cycle and ribosomal proteins decreased in S. acuminatus. In contrast, proteins associated with the photosynthetic machinery, except for F-type ATPase, were increased in the N+ group (N+, 3 vs. 9 days and 3 days, N+ vs. N-). Under low nitrogen supply, proteins involved in central carbon metabolism, fatty acid synthesis and branched-chain amino acid metabolism were increased, whereas the abundance of proteins of the photosynthetic machinery had decreased, with exception of PSI (N-, 3 vs. 9 days and 9 days, N+ vs. N-). Collectively, the current study has provided a basis for the metabolic engineering of S. acuminatus for biofuel production.
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Affiliation(s)
- Ying Zhang
- Institute of Hydrobiology, Jinan University, Guangzhou, 510632, People's Republic of China
| | - Huijuan Wu
- Institute of Hydrobiology, Jinan University, Guangzhou, 510632, People's Republic of China
| | - Mingzhe Sun
- Institute of Hydrobiology, Jinan University, Guangzhou, 510632, People's Republic of China
| | - Qianqian Peng
- Institute of Hydrobiology, Jinan University, Guangzhou, 510632, People's Republic of China
| | - Aifen Li
- Institute of Hydrobiology, Jinan University, Guangzhou, 510632, People's Republic of China.
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13
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Ferroni L, Giovanardi M, Poggioli M, Baldisserotto C, Pancaldi S. Enhanced photosynthetic linear electron flow in mixotrophic green microalga Ettlia oleoabundans UTEX 1185. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 130:215-223. [PMID: 30014925 DOI: 10.1016/j.plaphy.2018.07.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 06/28/2018] [Accepted: 07/02/2018] [Indexed: 06/08/2023]
Abstract
Basic understanding of the photosynthetic physiology of the oleaginous green microalga Ettlia oleoabundans is still very limited, including the modulation of the photosynthetic membrane upon metabolism conversion from autotrophy to mixotrophy. It was previously reported that, upon glucose supply in the culture medium, E. oleoabundans preserves photosystem II (PSII) from degradation by virtue of a higher packing of thylakoid complexes. In this work, it was investigated whether in the mixotrophic exponential growth phase the PSII activity is merely preserved or even enhanced. Modulated fluorescence parameters were then recorded under short-term treatments with increasing irradiance values of white light. It was found that the mixotrophic microalga down-regulated the chlororespiratory electron recycling from photosystem I (PSI), but enhanced the linear electron flow from PSII to PSI. Ability to keep PSII more open than in autotrophic growth conditions indicated that the respiration of the glucose taken up from the medium fed the carbon fixing reactions with CO2. The overall electron poise was indeed well regulated, with a lesser need for thermal dissipation of excess absorbed energy. It is proposed that the significant, though small, increase in PSII maximum quantum yield in mixotrophic cells just reflects an improved light energy use and an increased photochemical capacity as compared to the autotrophic cells.
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Affiliation(s)
- Lorenzo Ferroni
- Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este 32, 44121, Ferrara, Italy
| | - Martina Giovanardi
- Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este 32, 44121, Ferrara, Italy
| | - Mariachiara Poggioli
- Department of Life Sciences and Biotechnology, University of Ferrara, C.so Ercole I d'Este 32, 44121, Ferrara, Italy
| | - Costanza Baldisserotto
- 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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Abramson BW, Lensmire J, Lin YT, Jennings E, Ducat DC. Redirecting carbon to bioproduction via a growth arrest switch in a sucrose-secreting cyanobacterium. ALGAL RES 2018. [DOI: 10.1016/j.algal.2018.05.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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15
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Ramanjaneyulu BT, Vishwakarma NK, Vidyacharan S, Adiyala PR, Kim DP. Towards Versatile Continuous-Flow Chemistry and Process Technology Via New Conceptual Microreactor Systems. B KOREAN CHEM SOC 2018. [DOI: 10.1002/bkcs.11467] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Bandaru T. Ramanjaneyulu
- Department of Chemical Engineering; Pohang University of Science and Technology (POSTECH); Pohang 37673 Korea
| | - Niraj K. Vishwakarma
- Department of Chemical Engineering; Pohang University of Science and Technology (POSTECH); Pohang 37673 Korea
| | - Shinde Vidyacharan
- Department of Chemical Engineering; Pohang University of Science and Technology (POSTECH); Pohang 37673 Korea
| | - Praveen Reddy Adiyala
- Department of Chemical Engineering; Pohang University of Science and Technology (POSTECH); Pohang 37673 Korea
| | - Dong-Pyo Kim
- Department of Chemical Engineering; Pohang University of Science and Technology (POSTECH); Pohang 37673 Korea
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Optimization of Photosynthetic Productivity in Contrasting Environments by Regulons Controlling Plant Form and Function. Int J Mol Sci 2018; 19:ijms19030872. [PMID: 29543762 PMCID: PMC5877733 DOI: 10.3390/ijms19030872] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/13/2018] [Accepted: 03/13/2018] [Indexed: 01/06/2023] Open
Abstract
We review the role of a family of transcription factors and their regulons in maintaining high photosynthetic performance across a range of challenging environments with a focus on extreme temperatures and water availability. Specifically, these transcription factors include CBFs (C-repeat binding factors) and DREBs (dehydration-responsive element-binding), with CBF/DREB1 primarily orchestrating cold adaptation and other DREBs serving in heat, drought, and salinity adaptation. The central role of these modulators in plant performance under challenging environments is based on (i) interweaving of these regulators with other key signaling networks (plant hormones and redox signals) as well as (ii) their function in integrating responses across the whole plant, from light-harvesting and sugar-production in the leaf to foliar sugar export and water import and on to the plant's sugar-consuming sinks (growth, storage, and reproduction). The example of Arabidopsisthaliana ecotypes from geographic origins with contrasting climates is used to describe the links between natural genetic variation in CBF transcription factors and the differential acclimation of plant anatomical and functional features needed to support superior photosynthetic performance in contrasting environments. Emphasis is placed on considering different temperature environments (hot versus cold) and light environments (limiting versus high light), on trade-offs between adaptations to contrasting environments, and on plant lines minimizing such trade-offs.
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Tadepalli S, Slocik JM, Gupta MK, Naik RR, Singamaneni S. Bio-Optics and Bio-Inspired Optical Materials. Chem Rev 2017; 117:12705-12763. [PMID: 28937748 DOI: 10.1021/acs.chemrev.7b00153] [Citation(s) in RCA: 174] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Through the use of the limited materials palette, optimally designed micro- and nanostructures, and tightly regulated processes, nature demonstrates exquisite control of light-matter interactions at various length scales. In fact, control of light-matter interactions is an important element in the evolutionary arms race and has led to highly engineered optical materials and systems. In this review, we present a detailed summary of various optical effects found in nature with a particular emphasis on the materials and optical design aspects responsible for their optical functionality. Using several representative examples, we discuss various optical phenomena, including absorption and transparency, diffraction, interference, reflection and antireflection, scattering, light harvesting, wave guiding and lensing, camouflage, and bioluminescence, that are responsible for the unique optical properties of materials and structures found in nature and biology. Great strides in understanding the design principles adapted by nature have led to a tremendous progress in realizing biomimetic and bioinspired optical materials and photonic devices. We discuss the various micro- and nanofabrication techniques that have been employed for realizing advanced biomimetic optical structures.
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Affiliation(s)
- Sirimuvva Tadepalli
- Department of Mechanical Engineering and Materials Science and Institute of Materials Science and Engineering, Washington University in St. Louis , St. Louis, Missouri 63130, United States
| | | | | | | | - Srikanth Singamaneni
- Department of Mechanical Engineering and Materials Science and Institute of Materials Science and Engineering, Washington University in St. Louis , St. Louis, Missouri 63130, United States
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18
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19
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Abramson BW, Kachel B, Kramer DM, Ducat DC. Increased Photochemical Efficiency in Cyanobacteria via an Engineered Sucrose Sink. PLANT & CELL PHYSIOLOGY 2016; 57:2451-2460. [PMID: 27742883 DOI: 10.1093/pcp/pcw169] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 09/25/2016] [Indexed: 06/06/2023]
Abstract
In plants, a limited capacity to utilize or export the end-products of the Calvin-Benson cycle (CB) from photosynthetically active source cells to non-photosynthetic sink cells can result in reduced carbon capture and photosynthetic electron transport (PET), and lowered photochemical efficiency. The down-regulation of photosynthesis caused by reduced capacity to utilize photosynthate has been termed 'sink limitation'. Recently, several cyanobacterial and algal strains engineered to overproduce target metabolites have exhibited increased photochemistry, suggesting that possible source-sink regulatory mechanisms may be involved. We directly examined photochemical properties following induction of a heterologous sucrose 'sink' in the unicellular cyanobacterium Synechococcus elongatus PCC 7942. We show that total photochemistry increases proportionally to the experimentally controlled rate of sucrose export. Importantly, the quantum yield of PSII (ΦII) increases in response to sucrose export while the PET chain becomes more oxidized from less PSI acceptor-side limitation, suggesting increased CB activity and a decrease in sink limitation. Enhanced photosynthetic activity and linear electron flow are detectable within hours of induction of the heterologous sink and are independent of pigmentation alterations or the ionic/osmotic effects of the induction system. These observations provide direct evidence that secretion of heterologous carbon bioproducts can be used as an alternative approach to improve photosynthetic efficiency, presumably by by-passing sink limitation. Our results also suggest that engineered microalgal production strains are valuable alternative models for examining photosynthetic sink limitation because they enable greater control and monitoring of metabolite fluxes relative to plants.
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Affiliation(s)
- Bradley W Abramson
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
- Department of Cell and Molecular Biology, Michigan State University, East Lansing, MI, USA
| | - Benjamin Kachel
- Department of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | - David M Kramer
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
| | - Daniel C Ducat
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
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20
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McCarthy A, Chung M, Ivanov AG, Krol M, Inman M, Maxwell DP, Hüner NPA. An established Arabidopsis thaliana var. Landsberg erecta cell suspension culture accumulates chlorophyll and exhibits a stay-green phenotype in response to high external sucrose concentrations. JOURNAL OF PLANT PHYSIOLOGY 2016; 199:40-51. [PMID: 27302005 DOI: 10.1016/j.jplph.2016.05.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 05/12/2016] [Accepted: 05/13/2016] [Indexed: 06/06/2023]
Abstract
An established cell suspension culture of Arabidopsis thaliana var. Landsberg erecta was grown in liquid media containing 0-15%(w/v) sucrose. Exponential growth rates of about 0.40d-1 were maintained between 1.5-6%(w/v) sucrose, which decreased to about 0.30d-1 between 6 and 15%(w/v) sucrose. Despite the presence of external sucrose, cells maintained a stay-green phenotype at 0-15% (w/v) sucrose. Sucrose stimulated transcript levels of genes involved in the chlorophyll biosynthetic pathway (ChlH, ChlI2, DVR). Although most of the genes associated with photosystem II and photosystem I reaction centers and light harvesting complexes as well as genes associated with the cytochrome b6f and the ATP synthase complexes were downregulated or remained unaffected by high sucrose, immunoblotting indicated that protein levels of PsaA, Lhcb2 and Rubisco per gram fresh weight changed minimallyon a Chl basis as a function of external sucrose concentration. The green cell culture was photosynthetically competent based on light-dependent, CO2-saturated rates of O2 evolution as well as Fv/Fm and P700 oxidation. Similar to Arabidopsis WT seedlings, the suspension cells etiolated in the dark and but remained green in the light. However, the exponential growth rate of the cell suspension cultures in the dark (0.45±0.07d-1) was comparable to that in the light (0.42±0.02d-1). High external sucrose levels induced feedback inhibition of photosynthesis as indicated by the increase in excitation pressure measured as a function of external sucrose concentration. Regardless, the cell suspension culture still maintained a stay-green phenotype in the light at sucrose concentrations from 0 to 15%(w/v) due, in part, to a stimulation of photoprotection through nonphotochemical quenching. The stay-green, sugar-insensitive phenotype of the cell suspension contrasted with the sugar-dependent, non-green phenotype of Arabidopsis Landsberg erecta WT seedlings grown at comparable external sucrose concentrations. It appears that the commonly used Arabidopsis thaliana var. Landsberg erecta cell suspension culture has undergone significant genetic change since its original generation in 1993. We suggest that this genetic alteration has inhibited the sucrose sensing/signaling pathway coupled with a stimulation of chlorophyll an accumulation in the light with minimal effects on the composition and function of its photosynthetic apparatus. Therefore, caution must be exercised in the interpretation of physiological and biochemical data obtained from experimental use of this culture in any comparison with wild-type Arabidopsis seedlings.
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Affiliation(s)
- Avery McCarthy
- Department of Biology and the Biotron Centre for Experimental Climate Change Research, University of Western Ontario, London, ON, N6A 5B7 Canada,.
| | - Michelle Chung
- Department of Biology and the Biotron Centre for Experimental Climate Change Research, University of Western Ontario, London, ON, N6A 5B7 Canada,.
| | - Alexander G Ivanov
- Department of Biology and the Biotron Centre for Experimental Climate Change Research, University of Western Ontario, London, ON, N6A 5B7 Canada,.
| | - Marianna Krol
- Department of Biology and the Biotron Centre for Experimental Climate Change Research, University of Western Ontario, London, ON, N6A 5B7 Canada,.
| | - Michael Inman
- Department of Biology and the Biotron Centre for Experimental Climate Change Research, University of Western Ontario, London, ON, N6A 5B7 Canada,.
| | - Denis P Maxwell
- Department of Biology and the Biotron Centre for Experimental Climate Change Research, University of Western Ontario, London, ON, N6A 5B7 Canada,.
| | - Norman P A Hüner
- Department of Biology and the Biotron Centre for Experimental Climate Change Research, University of Western Ontario, London, ON, N6A 5B7 Canada,.
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21
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Baldisserotto C, Popovich C, Giovanardi M, Sabia A, Ferroni L, Constenla D, Leonardi P, Pancaldi S. Photosynthetic aspects and lipid profiles in the mixotrophic alga Neochloris oleoabundans as useful parameters for biodiesel production. ALGAL RES 2016. [DOI: 10.1016/j.algal.2016.03.022] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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22
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de Mooij T, de Vries G, Latsos C, Wijffels RH, Janssen M. Impact of light color on photobioreactor productivity. ALGAL RES 2016. [DOI: 10.1016/j.algal.2016.01.015] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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23
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Cambié D, Bottecchia C, Straathof NJW, Hessel V, Noël T. Applications of Continuous-Flow Photochemistry in Organic Synthesis, Material Science, and Water Treatment. Chem Rev 2016; 116:10276-341. [PMID: 26935706 DOI: 10.1021/acs.chemrev.5b00707] [Citation(s) in RCA: 882] [Impact Index Per Article: 110.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Continuous-flow photochemistry in microreactors receives a lot of attention from researchers in academia and industry as this technology provides reduced reaction times, higher selectivities, straightforward scalability, and the possibility to safely use hazardous intermediates and gaseous reactants. In this review, an up-to-date overview is given of photochemical transformations in continuous-flow reactors, including applications in organic synthesis, material science, and water treatment. In addition, the advantages of continuous-flow photochemistry are pointed out and a thorough comparison with batch processing is presented.
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Affiliation(s)
- Dario Cambié
- Department of Chemical Engineering and Chemistry, Micro Flow Chemistry and Process Technology, Eindhoven University of Technology , Den Dolech 2, 5600 MB Eindhoven, The Netherlands
| | - Cecilia Bottecchia
- Department of Chemical Engineering and Chemistry, Micro Flow Chemistry and Process Technology, Eindhoven University of Technology , Den Dolech 2, 5600 MB Eindhoven, The Netherlands
| | - Natan J W Straathof
- Department of Chemical Engineering and Chemistry, Micro Flow Chemistry and Process Technology, Eindhoven University of Technology , Den Dolech 2, 5600 MB Eindhoven, The Netherlands
| | - Volker Hessel
- Department of Chemical Engineering and Chemistry, Micro Flow Chemistry and Process Technology, Eindhoven University of Technology , Den Dolech 2, 5600 MB Eindhoven, The Netherlands
| | - Timothy Noël
- Department of Chemical Engineering and Chemistry, Micro Flow Chemistry and Process Technology, Eindhoven University of Technology , Den Dolech 2, 5600 MB Eindhoven, The Netherlands.,Department of Organic Chemistry, Ghent University , Krijgslaan 281 (S4), 9000 Ghent, Belgium
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24
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Lim CH, Holder AM, Hynes JT, Musgrave CB. Catalytic Reduction of CO2 by Renewable Organohydrides. J Phys Chem Lett 2015; 6:5078-5092. [PMID: 26722706 DOI: 10.1021/acs.jpclett.5b01827] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Dihydropyridines are renewable organohydride reducing agents for the catalytic reduction of CO2 to MeOH. Here we discuss various aspects of this important reduction. A centerpiece, which illustrates various general principles, is our theoretical catalytic mechanism for CO2 reduction by successive hydride transfers (HTs) and proton transfers (PTs) from the dihydropyridine PyH2 obtained by 1H(+)/1e(-)/1H(+)/1e(-) reductions of pyridine. The Py/PyH2 redox couple is analogous to NADP(+)/NADPH in that both are driven to effect HTs by rearomatization. High-energy radical intermediates and their associated high barriers/overpotentials are avoided because HT involves a 2e(-) reduction. A HT-PT sequence dictates that the reduced intermediates be protonated prior to further reduction for ultimate MeOH formation; these protonations are aided by biased cathodes that significantly lower the local pH. In contrast, cathodes that efficiently reduce H(+) such as Pt and Pd produce H2 and create a high interfacial pH, both obstructing dihydropyridine production and formate protonation and thus ultimately CO2 reduction by HTPTs. The role of water molecule proton relays is discussed. Finally, we suggest future CO2 reduction strategies by organic (photo)catalysts.
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Affiliation(s)
| | - Aaron M Holder
- National Renewable Energy Laboratory , Golden, Colorado 80401, United States
| | - James T Hynes
- Chemistry Department, Ecole Normale Supérieure-PSL Research University, Sorbonne Universités-UPMC University Paris 06, CNRS UMR 8640 Pasteur , 24 rue Lhomond, 75005 Paris, France
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25
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Duffy CD, Ruban AV. Dissipative pathways in the photosystem-II antenna in plants. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2015; 152:215-26. [DOI: 10.1016/j.jphotobiol.2015.09.011] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 09/07/2015] [Accepted: 09/11/2015] [Indexed: 10/23/2022]
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26
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Schlau-Cohen GS. Principles of light harvesting from single photosynthetic complexes. Interface Focus 2015; 5:20140088. [PMID: 26052423 DOI: 10.1098/rsfs.2014.0088] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Photosynthetic systems harness sunlight to power most life on Earth. In the initial steps of photosynthetic light harvesting, absorbed energy is converted to chemical energy with near-unity quantum efficiency. This is achieved by an efficient, directional and regulated flow of energy through a network of proteins. Here, we discuss the following three key principles of this flow and of photosynthetic light harvesting: thermal fluctuations of the protein structure; intrinsic conformational switches with defined functional consequences; and environmentally triggered conformational switches. Through these principles, photosynthetic systems balance two types of operational costs: metabolic costs, or the cost of maintaining and running the molecular machinery, and opportunity costs, or the cost of losing any operational time. Understanding how the molecular machinery and dynamics are designed to balance these costs may provide a blueprint for improved artificial light-harvesting devices. With a multi-disciplinary approach combining knowledge of biology, this blueprint could lead to low-cost and more effective solar energy conversion. Photosynthetic systems achieve widespread light harvesting across the Earth's surface; in the face of our growing energy needs, this is functionality we need to replicate, and perhaps emulate.
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Affiliation(s)
- G S Schlau-Cohen
- Department of Chemistry , Massachusetts Institute of Technology , 77 Massachusetts Avenue, 6-225, Cambridge, MA 02139 , USA
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27
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Heinrich JM, Irazoqui HA. Kinetic Model of Photoautotrophic Growth of Chlorella sp. Microalga, Isolated from the Setúbal Lagoon. Photochem Photobiol 2015; 91:1095-102. [PMID: 25994809 DOI: 10.1111/php.12468] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 05/09/2015] [Indexed: 11/30/2022]
Abstract
In this work, a kinetic expression relating light availability in the culture medium with the rate of microalgal growth is obtained. This expression, which is valid for low illumination conditions, was derived from the reactions that take part in the light-dependent stage of photosynthesis. The kinetic expression obtained is a function of the biomass concentration in the culture, as well as of the local volumetric rate of absorption of photons, and only includes two adjustable parameters. To determine the value of these parameters and to test the validity of the hypotheses made, autotrophic cultures of the Chlorella sp. strain were carried out in a modified BBM medium at three CO2 concentrations in the gas stream, namely 0.034%, 0.34% and 3.4%. Moreover, the local volumetric rate of photon absorption was predicted based on a physical model of the interaction of the radiant energy with the suspended biomass, together with a Monte Carlo simulation algorithm. The proposed intrinsic expression of the biomass growth rate, together with the Monte Carlo radiation field simulator, are key to scale up photobioreactors when operating under low irradiation conditions, independently of the configuration of the reactor and of its light source.
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Affiliation(s)
- Josué Miguel Heinrich
- Group of Innovation on Bio-processes Engineering, Institute for the Technological Development of the Chemical Industry (INTEC), National Council of Scientific and Technological Research (CONICET) and University of Litoral (UNL), Santa Fe, Argentina.,Group of Innovation on Bio-processes Engineering, Department of Biochemistry and Biological Sciences (FBCB), University of Litoral (UNL), Santa Fe, Argentina
| | - Horacio Antonio Irazoqui
- Group of Innovation on Bio-processes Engineering, Institute for the Technological Development of the Chemical Industry (INTEC), National Council of Scientific and Technological Research (CONICET) and University of Litoral (UNL), Santa Fe, Argentina.,Group of Innovation on Bio-processes Engineering, Department of Biochemistry and Biological Sciences (FBCB), University of Litoral (UNL), Santa Fe, Argentina
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28
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Zhou J, Zeng L, Liu J, Xing D. Manipulation of the Xanthophyll Cycle Increases Plant Susceptibility to Sclerotinia sclerotiorum. PLoS Pathog 2015; 11:e1004878. [PMID: 25993128 PMCID: PMC4439079 DOI: 10.1371/journal.ppat.1004878] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 04/13/2015] [Indexed: 11/19/2022] Open
Abstract
The xanthophyll cycle is involved in dissipating excess light energy to protect the photosynthetic apparatus in a process commonly assessed from non-photochemical quenching (NPQ) of chlorophyll fluorescence. Here, it is shown that the xanthophyll cycle is modulated by the necrotrophic pathogen Sclerotinia sclerotiorum at the early stage of infection. Incubation of Sclerotinia led to a localized increase in NPQ even at low light intensity. Further studies showed that this abnormal change in NPQ was closely correlated with a decreased pH caused by Sclerotinia-secreted oxalate, which might decrease the ATP synthase activity and lead to a deepening of thylakoid lumen acidification under continuous illumination. Furthermore, suppression (with dithiothreitol) or a defect (in the npq1-2 mutant) of violaxanthin de-epoxidase (VDE) abolished the Sclerotinia-induced NPQ increase. HPLC analysis showed that the Sclerotinia-inoculated tissue accumulated substantial quantities of zeaxanthin at the expense of violaxanthin, with a corresponding decrease in neoxanthin content. Immunoassays revealed that the decrease in these xanthophyll precursors reduced de novo abscisic acid (ABA) biosynthesis and apparently weakened tissue defense responses, including ROS induction and callose deposition, resulting in enhanced plant susceptibility to Sclerotinia. We thus propose that Sclerotinia antagonizes ABA biosynthesis to suppress host defense by manipulating the xanthophyll cycle in early pathogenesis. These findings provide a model of how photoprotective metabolites integrate into the defense responses, and expand the current knowledge of early plant-Sclerotinia interactions at infection sites.
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Affiliation(s)
- Jun Zhou
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, China
| | - Lizhang Zeng
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, China
| | - Jian Liu
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, China
| | - Da Xing
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, China
- * E-mail: ,
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29
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Demmig-Adams B, Muller O, Stewart JJ, Cohu CM, Adams WW. Chloroplast thylakoid structure in evergreen leaves employing strong thermal energy dissipation. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2015; 152:357-66. [PMID: 25843771 DOI: 10.1016/j.jphotobiol.2015.03.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 03/16/2015] [Accepted: 03/18/2015] [Indexed: 11/26/2022]
Abstract
In nature, photosynthetic organisms cope with highly variable light environments--intensities varying over orders of magnitudes as well as rapid fluctuations over seconds-to-minutes--by alternating between (a) highly effective absorption and photochemical conversion of light levels limiting to photosynthesis and (b) powerful photoprotective thermal dissipation of potentially damaging light levels exceeding those that can be utilized in photosynthesis. Adjustments of the photosynthetic apparatus to changes in light environment involve biophysical, biochemical, and structural adjustments. We used electron micrographs to assess overall thylakoid grana structure in evergreen species that exhibit much stronger maximal levels of thermal energy dissipation than the more commonly studied annual species. Our findings indicate an association between partial or complete unstacking of thylakoid grana structure and strong reversible thermal energy dissipation that, in contrast to what has been reported for annual species with much lower maximal levels of energy dissipation, is similar to what is seen under photoinhibitory conditions. For a tropical evergreen with tall grana stacks, a loosening, or vertical unstacking, of grana was seen in sun-grown plants exhibiting pronounced pH-dependent, rapidly reversible thermal energy dissipation as well as for sudden low-to-high-light transfer of shade-grown plants that responded with photoinhibition, characterized by strong dark-sustained, pH-independent thermal energy dissipation and photosystem II (PSII) inactivation. On the other hand, full-sun exposed subalpine confers with rather short grana stacks transitioned from autumn to winter via conversion of most thylakoids from granal to stromal lamellae concomitant with photoinhibitory photosynthetic inactivation and sustained thermal energy dissipation. We propose that these two types of changes (partial or complete unstacking of grana) in thylakoid arrangement are both associated with the strong non-photochemical quenching (NPQ) of chlorophyll fluorescence (a measure of photoprotective thermal energy dissipation) unique to evergreen species rather than with PSII inactivation per se.
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Affiliation(s)
- Barbara Demmig-Adams
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309-0334, USA.
| | - Onno Muller
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309-0334, USA
| | - Jared J Stewart
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309-0334, USA
| | - Christopher M Cohu
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309-0334, USA
| | - William W Adams
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309-0334, USA
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