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Ortega-Martínez P, Nikkanen L, Wey LT, Florencio FJ, Allahverdiyeva Y, Díaz-Troya S. Glycogen synthesis prevents metabolic imbalance and disruption of photosynthetic electron transport from photosystem II during transition to photomixotrophy in Synechocystis sp. PCC 6803. THE NEW PHYTOLOGIST 2024; 243:162-179. [PMID: 38706429 DOI: 10.1111/nph.19793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 04/17/2024] [Indexed: 05/07/2024]
Abstract
Some cyanobacteria can grow photoautotrophically or photomixotrophically by using simultaneously CO2 and glucose. The switch between these trophic modes and the role of glycogen, their main carbon storage macromolecule, was investigated. We analysed the effect of glucose addition on the physiology, metabolic and photosynthetic state of Synechocystis sp. PCC 6803 and mutants lacking phosphoglucomutase and ADP-glucose pyrophosphorylase, with limitations in glycogen synthesis. Glycogen acted as a metabolic buffer: glucose addition increased growth and glycogen reserves in the wild-type (WT), but arrested growth in the glycogen synthesis mutants. Already 30 min after glucose addition, metabolites from the Calvin-Benson-Bassham cycle and the oxidative pentose phosphate shunt increased threefold more in the glycogen synthesis mutants than the WT. These alterations substantially affected the photosynthetic performance of the glycogen synthesis mutants, as O2 evolution and CO2 uptake were both impaired. We conclude that glycogen synthesis is essential during transitions to photomixotrophy to avoid metabolic imbalance that induces inhibition of electron transfer from PSII and subsequently accumulation of reactive oxygen species, loss of PSII core proteins, and cell death. Our study lays foundations for optimising photomixotrophy-based biotechnologies through understanding the coordination of the crosstalk between photosynthetic electron transport and metabolism.
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Affiliation(s)
- Pablo Ortega-Martínez
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Américo Vespucio 49, Sevilla, 41092, Spain
- Departamento de Bioquímica Vegetal y Biología Molecular, Facultad de Biología, Universidad de Sevilla, Profesor García González s/n, Sevilla, 41012, Spain
| | - Lauri Nikkanen
- Molecular Plant Biology, Department of Life Technologies, University of Turku, Turku, FI-20014, Finland
| | - Laura T Wey
- Molecular Plant Biology, Department of Life Technologies, University of Turku, Turku, FI-20014, Finland
| | - Francisco J Florencio
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Américo Vespucio 49, Sevilla, 41092, Spain
- Departamento de Bioquímica Vegetal y Biología Molecular, Facultad de Biología, Universidad de Sevilla, Profesor García González s/n, Sevilla, 41012, Spain
| | - Yagut Allahverdiyeva
- Molecular Plant Biology, Department of Life Technologies, University of Turku, Turku, FI-20014, Finland
| | - Sandra Díaz-Troya
- Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Américo Vespucio 49, Sevilla, 41092, Spain
- Departamento de Bioquímica Vegetal y Biología Molecular, Facultad de Biología, Universidad de Sevilla, Profesor García González s/n, Sevilla, 41012, Spain
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2
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Belyaeva NE, Bulychev AA, Klementiev KE, Paschenko VZ, Riznichenko GY, Rubin AB. Comparative modeling of fluorescence and P700 induction kinetics for alga Scenedesmus sp. obliques and cyanobacterium Synechocystis sp. PCC 6803. Role of state 2-state 1 transitions and redox state of plastoquinone pool. Cell Biochem Biophys 2024; 82:729-745. [PMID: 38340281 DOI: 10.1007/s12013-024-01224-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 01/24/2024] [Indexed: 02/12/2024]
Abstract
The model of thylakoid membrane system (T-M model) (Belyaeva et al. Photosynth Res 2019, 140:1-19) has been improved in order to analyze the induction data for dark-adapted samples of algal (Scenedesmus obliques) and cyanobacterial (Synechocystis sp. PCC 6803) cells. The fluorescence induction (FI) curves of Scenedesmus were measured at light exposures of 5 min, while FI and P700 redox transformations of Synechocystis were recorded in parallel for 100 s intervals. Kinetic data comprising the OJIP-SMT fluorescence induction and OABCDEF P700+ absorbance changes were used to study the processes underlying state transitions qT2→1 and qT1→2 associated with the increase/decrease in Chl fluorescence emission. A formula with the Hill kinetics (Ebenhöh et al. Philos Trans R Soc B 2014, 369:20130223) was introduced into the T-M model, with a new variable to imitate the flexible size of antenna AntM(t) associated with PSII. Simulations revealed that the light-harvesting capacity of PSII increases with a corresponding decrease for that of PSI upon the qT2→1 transition induced by plastoquinone (PQ) pool oxidation. The complete T-M model fittings were attained on Scenedesmus or Synechocystis fast waves OJIPS of FI, while SMT wave of FI was reproduced at intervals shorter than 5 min. Also the fast P700 redox transitions (OABC) for Synechocystis were fitted exactly. Reasonable sets of algal and cyanobacterial electron/proton transfer (ET/PT) parameters were found. In the case of Scenedesmus, ET/PT traits remained the same irrespective of modeling with or without qT2→1 transitions. Simulations indicated a high extent (20%) of the PQ pool reduction under dark conditions in Synechocystis compared to 2% in Scenedesmus.
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Affiliation(s)
- N E Belyaeva
- Biological Faculty, Moscow State University, Moscow, 119234, Russia.
| | - A A Bulychev
- Biological Faculty, Moscow State University, Moscow, 119234, Russia
| | - K E Klementiev
- Biological Faculty, Moscow State University, Moscow, 119234, Russia
- Biological Faculty, Shenzhen MSU-BIT University, Shenzhen, 518172, China
| | - V Z Paschenko
- Biological Faculty, Moscow State University, Moscow, 119234, Russia
| | - G Yu Riznichenko
- Biological Faculty, Moscow State University, Moscow, 119234, Russia
| | - A B Rubin
- Biological Faculty, Moscow State University, Moscow, 119234, Russia
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3
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Song X, Kong F, Liu BF, Song Q, Ren NQ, Ren HY. Combined transcriptomic and metabolomic analyses of temperature response of microalgae using waste activated sludge extracts for promising biodiesel production. WATER RESEARCH 2024; 251:121120. [PMID: 38237459 DOI: 10.1016/j.watres.2024.121120] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 12/05/2023] [Accepted: 01/07/2024] [Indexed: 02/12/2024]
Abstract
Waste activated sludge (WAS) as one of the major pollutants with a significant annual production, has garnered significant attention regarding its treatment and utilization. If improperly discharged, it not only caused environmental pollution but also led to the wastage of valuable resources. In this study, the microalgae growth and lipid accumulation using waste activated sludge extracts (WASE) under different temperature conditions were investigated. The highest lipid content (59.13%) and lipid productivity (80.41 mg L-1 d-1) were obtained at cultivation temperatures of 10 and 25 °C, respectively. It was found that microalgae can effectively utilize TN/TP/NH4+-N and other nutrients of WASE. The highest utilization rates of TP, TN and NH4+-N were achieved at a cultivation temperature of 10 °C, reaching 84.97, 77.49 and 92.32%, respectively. The algal fatty acids had carbon chains predominantly ranging from C14 to C18, making them suitable for biodiesel production. Additionally, a comprehensive analysis of transcriptomics and metabolomics revealed up-regulation of genes associated with triglyceride assembly, the antioxidant system of algal cells, and cellular autophagy, as well as the accumulation of metabolites related to the tricarboxylic acid (TCA) cycle and lipids. This study offers novel insights into the microscopic mechanisms of microalgae culture using WASE and approaches for the resource utilization of sludge.
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Affiliation(s)
- Xueting Song
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Fanying Kong
- School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China
| | - Bing-Feng Liu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Qingqing Song
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Nan-Qi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Hong-Yu Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China.
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Napaumpaiporn P, Ogawa T, Sonoike K, Nishiyama Y. Improved capacity for the repair of photosystem II via reinforcement of the translational and antioxidation systems in Synechocystis sp. PCC 6803. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2024; 117:1165-1178. [PMID: 37983611 DOI: 10.1111/tpj.16551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 10/31/2023] [Accepted: 11/06/2023] [Indexed: 11/22/2023]
Abstract
In the cyanobacterium Synechocystis sp. PCC 6803, translation factor EF-Tu is inactivated by reactive oxygen species (ROS) via oxidation of Cys82 and the oxidation of EF-Tu enhances the inhibition of the repair of photosystem II (PSII) by suppressing protein synthesis. In our present study, we generated transformants of Synechocystis that overexpressed a mutated form of EF-Tu, designated EF-Tu (C82S), in which Cys82 had been replaced by a Ser residue, and ROS-scavenging enzymes individually or together. Expression of EF-Tu (C82S) alone in Synechocystis enhanced the repair of PSII under strong light, with the resultant mitigation of PSII photoinhibition, but it stimulated the production of ROS. However, overexpression of superoxide dismutase and catalase, together with the expression of EF-Tu (C82S), lowered intracellular levels of ROS and enhanced the repair of PSII more significantly under strong light, via facilitation of the synthesis de novo of the D1 protein. By contrast, the activity of photosystem I was hardly affected in wild-type cells and in all the lines of transformed cells under the same strong-light conditions. Furthermore, transformed cells that overexpressed EF-Tu (C82S), superoxide dismutase, and catalase were able to survive longer under stronger light than wild-type cells. Thus, the reinforced capacity for both protein synthesis and ROS scavenging allowed both photosynthesis and cell proliferation to tolerate strong light.
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Affiliation(s)
- Pornpan Napaumpaiporn
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Takako Ogawa
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Kintake Sonoike
- Faculty of Education and Integrated Arts and Sciences, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo, 162-8480, Japan
| | - Yoshitaka Nishiyama
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570, Japan
- Green Bioscience Research Area, Strategic Research Center, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570, Japan
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Tüllinghoff A, Djaya‐Mbissam H, Toepel J, Bühler B. Light-driven redox biocatalysis on gram-scale in Synechocystis sp. PCC 6803 via an in vivo cascade. PLANT BIOTECHNOLOGY JOURNAL 2023; 21:2074-2083. [PMID: 37439151 PMCID: PMC10502755 DOI: 10.1111/pbi.14113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/08/2023] [Accepted: 06/18/2023] [Indexed: 07/14/2023]
Abstract
The photosynthetic light reaction in cyanobacteria constitutes a highly attractive tool for productive biocatalysis, as it can provide redox reactions with high-energy reduction equivalents using sunlight and water as sources of energy and electrons, respectively. Here, we describe the first artificial light-driven redox cascade in Synechocystis sp. PCC 6803 to convert cyclohexanone to the polymer building block 6-hydroxyhexanoic acid (6-HA). Co-expression of a Baeyer-Villiger monooxygenase (BVMO) and a lactonase, both from Acidovorax sp. CHX100, enabled this two-step conversion with an activity of up to 63.1 ± 1.0 U/gCDW without accumulating inhibitory ε-caprolactone. Thereby, one of the key limitations of biocatalytic reactions, that is, reactant inhibition or toxicity, was overcome. In 2 L stirred-tank-photobioreactors, the process could be stabilized for 48 h, forming 23.50 ± 0.84 mm (3.11 ± 0.12 g/L) 6-HA. The high specificity enabling a product yield (YP/S ) of 0.96 ± 0.01 mol/mol and the remarkable biocatalyst-related yield of 3.71 ± 0.21 g6-HA /gCDW illustrate the potential of producing this non-toxic product in a synthetic cascade. The fine-tuning of the energy burden on the catalyst was found to be crucial, which indicates a limitation by the metabolic capacity of the cells possibly being compromised by biocatalysis-related reductant withdrawal. Intriguingly, energy balancing revealed that the biotransformation could tap surplus electrons derived from the photosynthetic light reaction and thereby relieve photosynthetic sink limitation. This study shows the feasibility of light-driven biocatalytic cascade operation in cyanobacteria and highlights respective metabolic limitations and engineering targets to unleash the full potential of photosynthesis.
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Affiliation(s)
- Adrian Tüllinghoff
- Helmholtz‐Centre for Environmental Research – UFZ, PermoserstrLeipzigGermany
| | | | - Jörg Toepel
- Helmholtz‐Centre for Environmental Research – UFZ, PermoserstrLeipzigGermany
| | - Bruno Bühler
- Helmholtz‐Centre for Environmental Research – UFZ, PermoserstrLeipzigGermany
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Shimakawa G. Electron transport in cyanobacterial thylakoid membranes: Are cyanobacteria simple models for photosynthetic organisms? JOURNAL OF EXPERIMENTAL BOTANY 2023:erad118. [PMID: 37025010 DOI: 10.1093/jxb/erad118] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Indexed: 06/19/2023]
Abstract
Cyanobacteria are structurally the simplest oxygenic phototrophs, which makes it difficult to understand the regulation of photosynthesis because the photosynthetic and respiratory processes share the same thylakoid membranes and cytosolic space. This review aimed to summarise the molecular mechanisms and in vivo activities of electron transport in cyanobacterial thylakoid membranes based on the latest progress in photosynthesis research in cyanobacteria. Photosynthetic linear electron transport for CO2 assimilation has the dominant electron flux in the thylakoid membranes. The capacity of O2 photoreduction in cyanobacteria is comparable to the photosynthetic CO2 assimilation, which is mediated by flavodiiron proteins. Additionally, cyanobacterial thylakoid membranes harbour the significant electron flux of respiratory electron transport through a homologue of respiratory complex I, which is also recognized as the part of cyclic electron transport chain if it is coupled with photosystem I in the light. Further, O2-independent alternative electron transports through hydrogenase and nitrate reductase function with reduced ferredoxin as the electron donor. Whereas all these electron transports are recently being understood one by one, the complexity as the whole regulatory system remains to be uncovered in near future.
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Affiliation(s)
- Ginga Shimakawa
- Department of Bioscience, School of Biological and Environmental Sciences, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo 669-1330, Japan
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Touloupakis E, Zittelli GC, Benavides AMS, Torzillo G. Growth and photosynthetic performance of Nostoc linckia (formerly N. calcicola) cells grown in BG11 and BG11 0 media. PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES : OFFICIAL JOURNAL OF THE EUROPEAN PHOTOCHEMISTRY ASSOCIATION AND THE EUROPEAN SOCIETY FOR PHOTOBIOLOGY 2022; 22:795-807. [PMID: 36550226 DOI: 10.1007/s43630-022-00353-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 12/07/2022] [Indexed: 12/24/2022]
Abstract
The biotechnological potential of Nostoc linckia as a biofertilizer and source of bioactive compounds makes it important to study its growth physiology and productivity. Since nitrogen is a fundamental component of N. linckia biomass, we compared the growth and biochemical composition of cultures grown in BG11 (i.e., in the presence of nitrate) and BG110 (in the absence of nitrate). Cultures grown in BG11 accumulated more cell biomass reaching a dry weight of 1.65 ± 0.06 g L-1, compared to 0.92 ± 0.01 g L-1 in BG110 after 240 h of culture. Biomass productivity was higher in culture grown in BG11 medium (average 317 ± 38 mg L-1 day-1) compared to that attained in BG110 (average 262 ± 37 mg L-1 day-1). The chlorophyll content of cells grown in BG11 increased continuously up to (39.0 ± 1.3 mg L-1), while in BG110 it increased much more slowly (13.6 ± 0.8 mg L-1). Biomass grown in BG11 had higher protein and phycobilin contents. However, despite the differences in biochemical composition and pigment concentration, between BG11 and BG110 cultures, both their net photosynthetic rates and maximum quantum yields of the photosystem II resulted in similar.
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Affiliation(s)
- Eleftherios Touloupakis
- Istituto di Ricerca sugli Ecosistemi Terrestri, CNR, Via Madonna del Piano, 10 Sesto Fiorentino, 50019, Florence, Italy
| | - Graziella Chini Zittelli
- Istituto per la Bioeconomia, CNR, Via Madonna del Piano 10 Sesto Fiorentino, 50019, Florence, Italy
| | - Ana Margarita Silva Benavides
- Centro de Investigación en Ciencias Del Mar y Limnologίa, Universidad de Costa Rica, San Pedro, San José, 2060, Costa Rica.,Escuela de Biologia, Universidad de Costa Rica, San Pedro, San José, 2060, Costa Rica
| | - Giuseppe Torzillo
- Istituto per la Bioeconomia, CNR, Via Madonna del Piano 10 Sesto Fiorentino, 50019, Florence, Italy. .,Centro de Investigación en Ciencias Del Mar y Limnologίa, Universidad de Costa Rica, San Pedro, San José, 2060, Costa Rica.
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Bulychev AA, Alova AV. Microfluidic interactions involved in chloroplast responses to plasma membrane excitation in Chara. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2022; 183:111-119. [PMID: 35576891 DOI: 10.1016/j.plaphy.2022.05.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 05/02/2022] [Accepted: 05/05/2022] [Indexed: 06/15/2023]
Abstract
Adaptation of plants to environmental changes involves the mechanisms of long-distance signaling. In characean algae, these mechanisms comprise the propagation of action potential (AP) and the rotational cytoplasmic streaming acting in cooperation with light-dependent exchange of ions and metabolites across the chloroplast envelope. Both excitability and cyclosis exert conspicuous effects on photosynthetic activity of chloroplasts but possible influence of cyclosis arrest on the coupling of AP stimulus to photosynthetic performance remained unexplored. In this study, fluidic interactions between anchored chloroplasts were allowed or restricted by illuminating the whole internode or a confined cell area (2 mm in diameter), respectively. Measurements of chlorophyll fluorescence parameters (F' and Fm') in cell regions located close to calcium crystal depositions revealed that the AP generation induced long-lasting Fm' oscillations that persisted in illuminated cells. The AP generation often induced the F' oscillations, whose number diminished upon the transfer of internodal cells from total to local background light. The results indicate that the AP-induced changes in photosynthetic parameters, F' in particular, have a complex origin and comprise the internal processes caused by the elevation of stromal Ca2+ concentration in the analyzed chloroplasts and the stages related to ion and metabolite exchange mediated by cytoplasmic streaming. It is supposed that the composition of flowing cytoplasm is heterogeneous due to the spatial alteration of calcified and noncalcified cell sites, but this heterogeneity is enhanced and can be visualized after the transient cessation and restoration of cytoplasmic streaming.
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Affiliation(s)
| | - Anna V Alova
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia.
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Kusama S, Miyake C, Nakanishi S, Shimakawa G. Dissection of respiratory and cyclic electron transport in Synechocystis sp. PCC 6803. JOURNAL OF PLANT RESEARCH 2022; 135:555-564. [PMID: 35680769 DOI: 10.1007/s10265-022-01401-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 06/01/2022] [Indexed: 06/15/2023]
Abstract
Cyclic electron transport (CET) is an attractive hypothesis for regulating photosynthetic electron transport and producing the additional ATP in oxygenic phototrophs. The concept of CET has been established in the last decades, and it is proposed to function in the progenitor of oxygenic photosynthesis, cyanobacteria. The in vivo activity of CET is frequently evaluated either from the redox state of the reaction center chlorophyll in photosystem (PS) I, P700, in the absence of PSII activity or by comparing PSI and PSII activities through the P700 redox state and chlorophyll fluorescence, respectively. The evaluation of CET activity, however, is complicated especially in cyanobacteria, where CET shares the intersystem chain, including plastoquinone, cytochrome b6/f complex, plastocyanin, and cytochrome c6, with photosynthetic linear electron transport (LET) and respiratory electron transport (RET). Here we sought to distinguish the in vivo electron transport rates in RET and CET in the cyanobacterium Synechocystis sp. PCC 6803. The reduction rate of oxidized P700 (P700+) decreased to less than 10% when PSII was inhibited, indicating that PSII is the dominant electron source to PSI but P700+ is also reduced by electrons derived from other sources. The oxidative pentose phosphate (OPP) pathway functions as the dominant electron source for RET, which was found to be inhibited by glycolaldehyde (GA). In the condition where the OPP pathway and respiratory terminal oxidases were inhibited by GA and KCN, the P700+ reduction rate was less than 1% of that without any inhibitors. This study indicate that the electron transport to PSI when PSII is inhibited is dominantly derived from the OPP pathway in Synechocystis sp. PCC 6803.
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Affiliation(s)
- Shoko Kusama
- Research Center for Solar Energy Chemistry, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
| | - Chikahiro Miyake
- Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501, Japan
| | - Shuji Nakanishi
- Research Center for Solar Energy Chemistry, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
| | - Ginga Shimakawa
- Research Center for Solar Energy Chemistry, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan.
- Department of Bioscience, School of Biological and Environmental Sciences, Kwansei-Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan.
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Blanc-Garin V, Veaudor T, Sétif P, Gontero B, Lemaire SD, Chauvat F, Cassier-Chauvat C. First in vivo analysis of the regulatory protein CP12 of the model cyanobacterium Synechocystis PCC 6803: Biotechnological implications. FRONTIERS IN PLANT SCIENCE 2022; 13:999672. [PMID: 36176677 PMCID: PMC9514657 DOI: 10.3389/fpls.2022.999672] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 08/22/2022] [Indexed: 05/09/2023]
Abstract
We report the first in vivo analysis of a canonical CP12 regulatory protein, namely the unique CP12 of the model cyanobacterium Synechocystis PCC 6803, which has the advantage of being able to grow photoautotrophically, photomixotrophically, and photoheterotrophically. The data showed that CP12 is dispensable to cell growth under standard (continuous) light and light/dark cycle, whereas it is essential for the catabolism of exogenously added glucose that normally sustains cell growth in absence of photosynthesis. Furthermore, to be active in glucose catabolism, CP12 requires its three conserved features: its AWD_VEEL motif and its two pairs of cysteine residues. Also interestingly, CP12 was found to regulate the redox equilibrium of NADPH, an activity involving its AWD_VEEL motif and its C-ter cysteine residues, but not its N-ter cysteine residues. This finding is important because NADPH powers up the methylerythritol 4-phosphate (MEP) pathway that synthesizes the geranyl-diphosphate (GPP) and farnesyl-diphosphate (FPP) metabolites, which can be transformed into high-value terpenes by recombinant cyanobacteria producing plant terpene synthase enzymes. Therefore, we have introduced into the Δcp12 mutant and the wild-type (control) strain our replicative plasmids directing the production of the monoterpene limonene and the sesquiterpene bisabolene. The photosynthetic production of both bisabolene and limonene appeared to be increased (more than two-fold) in the Δcp12 mutant as compared to the WT strain. Furthermore, the level of bisabolene production was also higher to those previously reported for various strains of Synechocystis PCC 6803 growing under standard (non-optimized) photoautotrophic conditions. Hence, the presently described Δcp12 strain with a healthy photoautotrophic growth and an increased capability to produce terpenes, is an attractive cell chassis for further gene manipulations aiming at engineering cyanobacteria for high-level photoproduction of terpenes.
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Affiliation(s)
- Victoire Blanc-Garin
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Théo Veaudor
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Pierre Sétif
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Brigitte Gontero
- Aix Marseille Univ, CNRS, BIP, UMR 7281, IMM, FR3479, 31 Chemin J. Aiguier, Marseille, France
| | - Stéphane D. Lemaire
- Laboratoire de Biologie Computationnelle et Quantitative, CNRS, UMR7238, Institut de Biologie Paris-Seine, Sorbonne Université, Paris, France
| | - Franck Chauvat
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Corinne Cassier-Chauvat
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Gif-sur-Yvette, France
- *Correspondence: Corinne Cassier-Chauvat,
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