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Udaypal, Goswami RK, Mehariya S, Verma P. Advances in microalgae-based carbon sequestration: Current status and future perspectives. ENVIRONMENTAL RESEARCH 2024; 249:118397. [PMID: 38309563 DOI: 10.1016/j.envres.2024.118397] [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: 11/14/2023] [Revised: 01/02/2024] [Accepted: 01/30/2024] [Indexed: 02/05/2024]
Abstract
The advancement in carbon dioxide (CO2) sequestration technology has received significant attention due to the adverse effects of CO2 on climate. The mitigation of the adverse effects of CO2 can be accomplished through its conversion into useful products or renewable fuels. In this regard, microalgae is a promising candidate due to its high photosynthesis efficiency, sustainability, and eco-friendly nature. Microalgae utilizes CO2 in the process of photosynthesis and generates biomass that can be utilized to produce various valuable products such as supplements, chemicals, cosmetics, biofuels, and other value-added products. However, at present microalgae cultivation is still restricted to producing value-added products due to high cultivation costs and lower CO2 sequestration efficiency of algal strains. Therefore, it is very crucial to develop novel techniques that can be cost-effective and enhance microalgal carbon sequestration efficiency. The main aim of the present manuscript is to explain how to optimize microalgal CO2 sequestration, integrate valuable product generation, and explore novel techniques like genetic manipulations, phytohormones, quantum dots, and AI tools to enhance the efficiency of CO2 sequestration. Additionally, this review provides an overview of the mass flow of different microalgae and their biorefinery, life cycle assessment (LCA) for achieving net-zero CO2 emissions, and the advantages, challenges, and future perspectives of current technologies. All of the reviewed approaches efficiently enhance microalgal CO2 sequestration and integrate value-added compound production, creating a green and economically profitable process.
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Affiliation(s)
- Udaypal
- Bioprocess and Bioenergy Laboratory (BPBEL), Department of Microbiology, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, Rajasthan, 305817, India
| | - Rahul Kumar Goswami
- Bioprocess and Bioenergy Laboratory (BPBEL), Department of Microbiology, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, Rajasthan, 305817, India
| | - Sanjeet Mehariya
- Algal Technology Program, Center for Sustainable Development, College of Arts and Sciences, Qatar University, Doha, 2713, Qatar
| | - Pradeep Verma
- Bioprocess and Bioenergy Laboratory (BPBEL), Department of Microbiology, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, Rajasthan, 305817, India.
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Kim M, Cazzaniga S, Jang J, Pivato M, Kim G, Ballottari M, Jin E. Photoautotrophic cultivation of a Chlamydomonas reinhardtii mutant with zeaxanthin as the sole xanthophyll. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:41. [PMID: 38486329 PMCID: PMC10941483 DOI: 10.1186/s13068-024-02483-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 02/24/2024] [Indexed: 03/17/2024]
Abstract
BACKGROUND Photosynthetic microalgae are known for their sustainable and eco-friendly potential to convert carbon dioxide into valuable products. Nevertheless, the challenge of self-shading due to high cell density has been identified as a drawback, hampering productivity in sustainable photoautotrophic mass cultivation. To address this issue, mutants with altered pigment composition have been proposed to allow a more efficient light diffusion but further study on the role of the different pigments is still needed to correctly engineer this process. RESULTS We here investigated the Chlamydomonas reinhardtii Δzl mutant with zeaxanthin as the sole xanthophyll. The Δzl mutant displayed altered pigment composition, characterized by lower chlorophyll content, higher chlorophyll a/b ratio, and lower chlorophyll/carotenoid ratio compared to the wild type (Wt). The Δzl mutant also exhibited a significant decrease in the light-harvesting complex II/Photosystem II ratio (LHCII/PSII) and the absence of trimeric LHCIIs. This significantly affects the organization and stability of PSII supercomplexes. Consequently, the estimated functional antenna size of PSII in the Δzl mutant was approximately 60% smaller compared to that of Wt, and reduced PSII activity was evident in this mutant. Notably, the Δzl mutant showed impaired non-photochemical quenching. However, the Δzl mutant compensated by exhibiting enhanced cyclic electron flow compared to Wt, seemingly offsetting the impaired PSII functionality. Consequently, the Δzl mutant achieved significantly higher cell densities than Wt under high-light conditions. CONCLUSIONS Our findings highlight significant changes in pigment content and pigment-protein complexes in the Δzl mutant compared to Wt, resulting in an advantage for high-density photoautotrophic cultivation. This advantage is attributed to the decreased chlorophyll content of the Δzl mutant, allowing better light penetration. In addition, the accumulated zeaxanthin in the mutant could serve as an antioxidant, offering protection against reactive oxygen species generated by chlorophylls.
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Affiliation(s)
- Minjae Kim
- Department of Life Science, Research Institute for Natural Sciences, Hanyang University, Seoul, 04763, Korea
| | | | - Junhwan Jang
- Department of Life Science, Research Institute for Natural Sciences, Hanyang University, Seoul, 04763, Korea
| | - Matteo Pivato
- Dipartimento di Biotecnologie, Università di Verona, Verona, Italy
| | - Gueeda Kim
- Department of Life Science, Research Institute for Natural Sciences, Hanyang University, Seoul, 04763, Korea
| | | | - EonSeon Jin
- Department of Life Science, Research Institute for Natural Sciences, Hanyang University, Seoul, 04763, Korea.
- Hanyang Institute of Bioscience and Biotechnology, Hanyang University, Seoul, 04763, Korea.
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Cano M, Krishnan A, Karns DA, Likhogrud MA, Weissman JC, Posewitz MC. Cas9 deletion of lutein biosynthesis in the marine alga Picochlorum celeri reduces photosynthetic pigments while sustaining high biomass productivity. Front Bioeng Biotechnol 2024; 11:1332461. [PMID: 38274009 PMCID: PMC10808502 DOI: 10.3389/fbioe.2023.1332461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 12/20/2023] [Indexed: 01/27/2024] Open
Abstract
Domestication of algae for food and renewable biofuels remains limited by the low photosynthetic efficiencies of processes that have evolved to be competitive for optimal light capture, incentivizing the development of large antennas in light-limiting conditions, thus decreasing efficient light utilization in cultivated ponds or photobioreactors. Reducing the pigment content to improve biomass productivity has been a strategy discussed for several decades and the ability to reduce pigment significantly is now fully at hand thanks to the widespread use of genome editing tools. Picochlorum celeri is one of the fastest growing marine algae identified and holds particular promise for outdoor cultivation, especially in saline water and warm climates. We show that while chlorophyll b is essential to sustain high biomass productivities under dense cultivation, removing Picochlorum celeri's main carotenoid, lutein, leads to a decreased total chlorophyll content, higher a/b ratio, reduced functional LHCII cross section and higher maximum quantum efficiencies at lower light intensities, resulting in an incremental increase in biomass productivity and increased PAR-to-biomass conversion efficiency. These findings further strengthen the existing strategies to improve photosynthetic efficiency and biomass production in algae.
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Affiliation(s)
- Melissa Cano
- Department of Chemistry, Colorado School of Mines, Golden, CO, United States
| | - Anagha Krishnan
- Department of Chemistry, Colorado School of Mines, Golden, CO, United States
| | - Devin A. Karns
- Department of Chemistry, Colorado School of Mines, Golden, CO, United States
| | - Maria A. Likhogrud
- ExxonMobil Technology and Engineering Company, Annandale, NJ, United States
| | - Joseph C. Weissman
- ExxonMobil Technology and Engineering Company, Annandale, NJ, United States
| | - Matthew C. Posewitz
- Department of Chemistry, Colorado School of Mines, Golden, CO, United States
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Krishnan A, Cano M, Karns DA, Burch TA, Likhogrud M, Aqui M, Bailey S, Verruto J, Lambert W, Kuzminov F, Naghipor M, Wang Y, Ebmeier CC, Weissman JC, Posewitz MC. Simultaneous CAS9 editing of cp SRP43, LHCA6, and LHCA7 in Picochlorum celeri lowers chlorophyll levels and improves biomass productivity. PLANT DIRECT 2023; 7:e530. [PMID: 37711644 PMCID: PMC10497401 DOI: 10.1002/pld3.530] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 08/03/2023] [Accepted: 08/17/2023] [Indexed: 09/16/2023]
Abstract
High cellular pigment levels in dense microalgal cultures contribute to excess light absorption. To improve photosynthetic yields in the marine microalga Picochlorum celeri, CAS9 gene editing was used to target the molecular chaperone cpSRP43. Depigmented strains (>50% lower chlorophyll) were generated, with proteomics showing attenuated levels of most light harvesting complex (LHC) proteins. Gene editing generated two types of cpSRP43 transformants with distinct lower pigment phenotypes: (i) a transformant (Δsrp43) with both cpSRP43 diploid alleles modified to encode non-functional polypeptides and (ii) a transformant (STR30309) with a 3 nt in-frame insertion in one allele at the CAS9 cut site (non-functional second allele), leading to expression of a modified cpSRP43. STR30309 has more chlorophyll than Δsrp43 but substantially less than wild type. To further decrease light absorption by photosystem I in STR30309, CAS9 editing was used to stack in disruptions of both LHCA6 and LHCA7 to generate STR30843, which has higher (5-24%) productivities relative to wild type in solar-simulating bioreactors. Maximal productivities required frequent partial harvests throughout the day. For STR30843, exemplary diel bioreactor yields of ~50 g m-2 day-1 were attained. Our results demonstrate diel productivity gains in P. celeri by lowering pigment levels.
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Affiliation(s)
- Anagha Krishnan
- Department of ChemistryColorado School of MinesGoldenColoradoUSA
| | - Melissa Cano
- Department of ChemistryColorado School of MinesGoldenColoradoUSA
| | - Devin A. Karns
- Department of ChemistryColorado School of MinesGoldenColoradoUSA
| | - Tyson A. Burch
- Department of ChemistryColorado School of MinesGoldenColoradoUSA
| | - Maria Likhogrud
- ExxonMobil Technology and Engineering CompanyAnnandaleNew JerseyUSA
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Nymark M, Finazzi G, Volpe C, Serif M, Fonseca DDM, Sharma A, Sanchez N, Sharma AK, Ashcroft F, Kissen R, Winge P, Bones AM. Loss of CpFTSY Reduces Photosynthetic Performance and Affects Insertion of PsaC of PSI in Diatoms. PLANT & CELL PHYSIOLOGY 2023; 64:583-603. [PMID: 36852859 DOI: 10.1093/pcp/pcad014] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 02/17/2023] [Accepted: 02/23/2023] [Indexed: 06/16/2023]
Abstract
The chloroplast signal recognition particle (CpSRP) receptor (CpFTSY) is a component of the CpSRP pathway that post-translationally targets light-harvesting complex proteins (LHCPs) to the thylakoid membranes in plants and green algae containing chloroplasts derived from primary endosymbiosis. In plants, CpFTSY also plays a major role in the co-translational incorporation of chloroplast-encoded subunits of photosynthetic complexes into the thylakoids. This role has not been demonstrated in green algae. So far, its function in organisms with chloroplasts derived from secondary endosymbiotic events has not been elucidated. Here, we report the generation and characterization of mutants lacking CpFTSY in the diatom Phaeodactylum tricornutum. We found that this protein is not involved in inserting LHCPs into thylakoid membranes, indicating that the post-translational part of the CpSRP pathway is not active in this group of microalgae. The lack of CpFTSY caused an increased level of photoprotection, low electron transport rates, inefficient repair of photosystem II (PSII), reduced growth, a strong decline in the PSI subunit PsaC and upregulation of proteins that might compensate for a non-functional co-translational CpSRP pathway during light stress conditions. The phenotype was highly similar to the one described for diatoms lacking another component of the co-translational CpSRP pathway, the CpSRP54 protein. However, in contrast to cpsrp54 mutants, only one thylakoid membrane protein, PetD of the Cytb6f complex, was downregulated in cpftsy. Our results point to a minor role for CpFTSY in the co-translational CpSRP pathway, suggesting that other mechanisms may partially compensate for the effect of a disrupted CpSRP pathway.
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Affiliation(s)
- Marianne Nymark
- Department of Biology, Norwegian University of Science and Technology, Trondheim N-7491, Norway
- Department of Fisheries and New Biomarine Industry, SINTEF Ocean, Trondheim 7010, Norway
| | - Giovanni Finazzi
- Cell & Plant Physiology Laboratory, Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG, LPCV, Grenoble 38000, France
| | - Charlotte Volpe
- Department of Biology, Norwegian University of Science and Technology, Trondheim N-7491, Norway
- Department of Fisheries and New Biomarine Industry, SINTEF Ocean, Trondheim 7010, Norway
| | - Manuel Serif
- Department of Biology, Norwegian University of Science and Technology, Trondheim N-7491, Norway
| | - Davi de Miranda Fonseca
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, NTNU, Trondheim N-7491, Norway
- Proteomics and Modomics Experimental Core Facility (PROMEC), NTNU and Central Administration, St. Olavs Hospital, The University Hospital in Trondheim, Trondheim N-7491, Norway
| | - Animesh Sharma
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, NTNU, Trondheim N-7491, Norway
- Proteomics and Modomics Experimental Core Facility (PROMEC), NTNU and Central Administration, St. Olavs Hospital, The University Hospital in Trondheim, Trondheim N-7491, Norway
| | - Nicolas Sanchez
- Department of Chemistry, Norwegian University of Science and Technology, Trondheim N-7491, Norway
| | - Amit Kumar Sharma
- Department of Biology, Norwegian University of Science and Technology, Trondheim N-7491, Norway
| | - Felicity Ashcroft
- Department of Biology, Norwegian University of Science and Technology, Trondheim N-7491, Norway
| | - Ralph Kissen
- Department of Biology, Norwegian University of Science and Technology, Trondheim N-7491, Norway
| | - Per Winge
- Department of Biology, Norwegian University of Science and Technology, Trondheim N-7491, Norway
| | - Atle Magnar Bones
- Department of Biology, Norwegian University of Science and Technology, Trondheim N-7491, Norway
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Advances in Genetic Engineering in Improving Photosynthesis and Microalgal Productivity. Int J Mol Sci 2023; 24:ijms24031898. [PMID: 36768215 PMCID: PMC9915242 DOI: 10.3390/ijms24031898] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/10/2023] [Accepted: 01/16/2023] [Indexed: 01/21/2023] Open
Abstract
Even though sunlight energy far outweighs the energy required by human activities, its utilization is a key goal in the field of renewable energies. Microalgae have emerged as a promising new and sustainable feedstock for meeting rising food and feed demand. Because traditional methods of microalgal improvement are likely to have reached their limits, genetic engineering is expected to allow for further increases in the photosynthesis and productivity of microalgae. Understanding the mechanisms that control photosynthesis will enable researchers to identify targets for genetic engineering and, in the end, increase biomass yield, offsetting the costs of cultivation systems and downstream biomass processing. This review describes the molecular events that happen during photosynthesis and microalgal productivity through genetic engineering and discusses future strategies and the limitations of genetic engineering in microalgal productivity. We highlight the major achievements in manipulating the fundamental mechanisms of microalgal photosynthesis and biomass production, as well as promising approaches for making significant contributions to upcoming microalgal-based biotechnology.
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7
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Leister D. Enhancing the light reactions of photosynthesis: Strategies, controversies, and perspectives. MOLECULAR PLANT 2023; 16:4-22. [PMID: 35996755 DOI: 10.1016/j.molp.2022.08.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 07/26/2022] [Accepted: 08/16/2022] [Indexed: 06/15/2023]
Abstract
Photosynthesis is central to life on Earth, employing sunlight, water, and carbon dioxide to produce chemical energy and oxygen. It is generally accepted that boosting its efficiency offers one promising way to increase crop yields under agronomically realistic conditions. Since the components, structure, and regulatory mechanisms of the light reactions of photosynthesis are well understood, concepts for enhancing the process have been suggested and partially tested. These approaches vary in complexity, from targeting single components to comprehensive redesign of the whole process on the scales from single cells or tissues to whole canopies. Attempts to enhance light utilization per leaf, by decreasing pigmentation, increasing levels of photosynthetic proteins, prolonging the lifespan of the photosynthetic machinery, or massive reconfiguration of the photosynthetic machinery and the incorporation of nanomaterials, are discussed in this review first. Secondly, strategies intended to optimize the acclimation of photosynthesis to changes in the environment are presented, including redesigning mechanisms to dissipate excess excitation energy (e.g., non-photochemical quenching) or reduction power (e.g., flavodiiron proteins). Moreover, schemes for improving acclimation, inspired by natural or laboratory-induced adaptation, are introduced. However, all these endeavors are still in an early exploratory phase and/or have not resulted in the desired outcome, largely because photosynthesis is embedded within large networks of closely interacting cellular and metabolic processes, which can vary among species and even cultivars. This explains why integrated, systems-wide approaches are required to achieve the breakthroughs required for effectively increasing crop yields.
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Affiliation(s)
- Dario Leister
- Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-University (LMU) Munich, Martinsried-Planegg, D-82152 Munich, Germany.
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8
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Zhang N, Mattoon EM, McHargue W, Venn B, Zimmer D, Pecani K, Jeong J, Anderson CM, Chen C, Berry JC, Xia M, Tzeng SC, Becker E, Pazouki L, Evans B, Cross F, Cheng J, Czymmek KJ, Schroda M, Mühlhaus T, Zhang R. Systems-wide analysis revealed shared and unique responses to moderate and acute high temperatures in the green alga Chlamydomonas reinhardtii. Commun Biol 2022; 5:460. [PMID: 35562408 PMCID: PMC9106746 DOI: 10.1038/s42003-022-03359-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 04/12/2022] [Indexed: 12/15/2022] Open
Abstract
Different intensities of high temperatures affect the growth of photosynthetic cells in nature. To elucidate the underlying mechanisms, we cultivated the unicellular green alga Chlamydomonas reinhardtii under highly controlled photobioreactor conditions and revealed systems-wide shared and unique responses to 24-hour moderate (35°C) and acute (40°C) high temperatures and subsequent recovery at 25°C. We identified previously overlooked unique elements in response to moderate high temperature. Heat at 35°C transiently arrested the cell cycle followed by partial synchronization, up-regulated transcripts/proteins involved in gluconeogenesis/glyoxylate-cycle for carbon uptake and promoted growth. But 40°C disrupted cell division and growth. Both high temperatures induced photoprotection, while 40°C distorted thylakoid/pyrenoid ultrastructure, affected the carbon concentrating mechanism, and decreased photosynthetic efficiency. We demonstrated increased transcript/protein correlation during both heat treatments and hypothesize reduced post-transcriptional regulation during heat may help efficiently coordinate thermotolerance mechanisms. During recovery after both heat treatments, especially 40°C, transcripts/proteins related to DNA synthesis increased while those involved in photosynthetic light reactions decreased. We propose down-regulating photosynthetic light reactions during DNA replication benefits cell cycle resumption by reducing ROS production. Our results provide potential targets to increase thermotolerance in algae and crops. A systems-wide analysis of the single-cell green alga Chlamydomonas reinhardti reveals shared and unique responses to moderate and acute high temperatures using multiple-level investigation of transcriptomics, proteomics, cell physiology, photosynthetic parameters, and cellular ultrastructure.
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Affiliation(s)
- Ningning Zhang
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA
| | - Erin M Mattoon
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA.,Plant and Microbial Biosciences Program, Division of Biology and Biomedical Sciences, Washington University in Saint Louis, St. Louis, Missouri, 63130, USA
| | - Will McHargue
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA.,Plant and Microbial Biosciences Program, Division of Biology and Biomedical Sciences, Washington University in Saint Louis, St. Louis, Missouri, 63130, USA
| | | | - David Zimmer
- TU Kaiserslautern, Kaiserslautern, 67663, Germany
| | - Kresti Pecani
- The Rockefeller University, New York, New York, 10065, USA
| | - Jooyeon Jeong
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA
| | - Cheyenne M Anderson
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA.,Plant and Microbial Biosciences Program, Division of Biology and Biomedical Sciences, Washington University in Saint Louis, St. Louis, Missouri, 63130, USA
| | - Chen Chen
- University of Missouri-Columbia, Columbia, Missouri, 65211, USA
| | - Jeffrey C Berry
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA
| | - Ming Xia
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA
| | - Shin-Cheng Tzeng
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA
| | - Eric Becker
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA
| | - Leila Pazouki
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA
| | - Bradley Evans
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA
| | - Fred Cross
- The Rockefeller University, New York, New York, 10065, USA
| | - Jianlin Cheng
- University of Missouri-Columbia, Columbia, Missouri, 65211, USA
| | - Kirk J Czymmek
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA
| | | | | | - Ru Zhang
- Donald Danforth Plant Science Center, St. Louis, Missouri, 63132, USA.
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9
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Grama SB, Liu Z, Li J. Emerging Trends in Genetic Engineering of Microalgae for Commercial Applications. Mar Drugs 2022; 20:285. [PMID: 35621936 PMCID: PMC9143385 DOI: 10.3390/md20050285] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 04/15/2022] [Accepted: 04/19/2022] [Indexed: 02/04/2023] Open
Abstract
Recently, microalgal biotechnology has received increasing interests in producing valuable, sustainable and environmentally friendly bioproducts. The development of economically viable production processes entails resolving certain limitations of microalgal biotechnology, and fast evolving genetic engineering technologies have emerged as new tools to overcome these limitations. This review provides a synopsis of recent progress, current trends and emerging approaches of genetic engineering of microalgae for commercial applications, including production of pharmaceutical protein, lipid, carotenoids and biohydrogen, etc. Photochemistry improvement in microalgae and CO2 sequestration by microalgae via genetic engineering were also discussed since these subjects are closely entangled with commercial production of the above mentioned products. Although genetic engineering of microalgae is proved to be very effective in boosting performance of production in laboratory conditions, only limited success was achieved to be applicable to industry so far. With genetic engineering technologies advancing rapidly and intensive investigations going on, more bioproducts are expected to be produced by genetically modified microalgae and even much more to be prospected.
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Affiliation(s)
- Samir B. Grama
- Laboratory of Natural Substances, Biomolecules and Biotechnological Applications, University of Oum El Bouaghi, Oum El Bouaghi 04000, Algeria;
| | - Zhiyuan Liu
- College of Marine Sciences, Hainan University, Haikou 570228, China;
| | - Jian Li
- College of Agricultural Sciences, Panzhihua University, Panzhihua 617000, China
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10
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Rathod MK, Nellaepalli S, Ozawa SI, Kuroda H, Kodama N, Bujaldon S, Wollman FA, Takahashi Y. Assembly Apparatus of Light-Harvesting Complexes: Identification of Alb3.1-cpSRP-LHCP Complexes in the Green Alga Chlamydomonas reinhardtii. PLANT & CELL PHYSIOLOGY 2022; 63:70-81. [PMID: 34592750 DOI: 10.1093/pcp/pcab146] [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: 06/19/2021] [Revised: 09/24/2021] [Accepted: 09/30/2021] [Indexed: 06/13/2023]
Abstract
The unicellular green alga, Chlamydomonas reinhardtii, contains many light-harvesting complexes (LHCs) associating chlorophylls a/b and carotenoids; the major LHCIIs (types I, II, III and IV) and minor light-harvesting complexes, CP26 and CP29, for photosystem II, as well as nine LHCIs (LHCA1-9), for photosystem I. A pale green mutant BF4 exhibited impaired accumulation of LHCs due to deficiency in the Alb3.1 gene, which encodes the insertase involved in insertion, folding and assembly of LHC proteins in the thylakoid membranes. To elucidate the molecular mechanism by which ALB3.1 assists LHC assembly, we complemented BF4 to express ALB3.1 fused with no, single or triple Human influenza hemagglutinin (HA) tag at its C-terminus (cAlb3.1, cAlb3.1-HA or cAlb3.1-3HA). The resulting complemented strains accumulated most LHC proteins comparable to wild-type (WT) levels. The affinity purification of Alb3.1-HA and Alb3.1-3HA preparations showed that ALB3.1 interacts with cpSRP43 and cpSRP54 proteins of the chloroplast signal recognition particle (cpSRP) and several LHC proteins; two major LHCII proteins (types I and III), two minor LHCII proteins (CP26 and CP29) and eight LHCI proteins (LHCA1, 2, 3, 4, 5, 6, 8 and 9). Pulse-chase labeling experiments revealed that the newly synthesized major LHCII proteins were transiently bound to the Alb3.1 complex. We propose that Alb3.1 interacts with cpSRP43 and cpSRP54 to form an assembly apparatus for most LHCs in the thylakoid membranes. Interestingly, photosystem I (PSI) proteins were also detected in the Alb3.1 preparations, suggesting that the integration of LHCIs to a PSI core complex to form a PSI-LHCI subcomplex occurs before assembled LHCIs dissociate from the Alb3.1-cpSRP complex.
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Affiliation(s)
- Mithun Kumar Rathod
- Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530 Japan
| | - Sreedhar Nellaepalli
- Research Institute for Interdisciplinary Science, Okayama University, Okayama, 700-8530 Japan
| | - Shin-Ichiro Ozawa
- Institute of Plant Science and Resources, Okayama University, Kurashiki, 710-0046 Japan
| | - Hiroshi Kuroda
- Research Institute for Interdisciplinary Science, Okayama University, Okayama, 700-8530 Japan
| | - Natsumi Kodama
- Research Institute for Interdisciplinary Science, Okayama University, Okayama, 700-8530 Japan
| | - Sandrine Bujaldon
- Institut de Biologie Physico-Chimique, UMR7141 CNRS-Sorbonne Université, Paris 75005, France
| | - Francis-André Wollman
- Institut de Biologie Physico-Chimique, UMR7141 CNRS-Sorbonne Université, Paris 75005, France
| | - Yuichiro Takahashi
- Research Institute for Interdisciplinary Science, Okayama University, Okayama, 700-8530 Japan
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11
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Jakhwal P, Kumar Biswas J, Tiwari A, Kwon EE, Bhatnagar A. Genetic and non-genetic tailoring of microalgae for the enhanced production of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) - A review. BIORESOURCE TECHNOLOGY 2022; 344:126250. [PMID: 34728356 DOI: 10.1016/j.biortech.2021.126250] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
The myriad health benefits associated with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) laid the path for their application in the functional foods and nutraceutical industries. Fish being primarily exploited for extraction of EPA and DHA are unsustainable sources; thus, oleaginous microalgae turn out to be an alternative sustainable source. This review paper aims to provide the recent developments in the context of enhancing EPA and DHA production by utilising non-genetic tailoring and genetic tailoring methods. We have also summarized the legislation, public perception, and possible risks associated with the usage of genetically modified microalgae focusing on EPA and DHA production.
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Affiliation(s)
- Parul Jakhwal
- Department of Separation Science, LUT School of Engineering Science, LUT University, Sammonkatu 12, FI-50130, Mikkeli, Finland
| | - Jayanta Kumar Biswas
- Enviromicrobiology, Ecotoxicology and Ecotechnology Research Laboratory, Department of Ecological Studies, University of Kalyani, Kalyani, Nadia 741235, West Bengal, India; International Centre for Ecological Engineering, University of Kalyani, Kalyani 741235, West Bengal, India
| | - Archana Tiwari
- Diatom Research Laboratory, Amity Institute of Biotechnology, Amity University, Noida, Uttar Pradesh 201301, India
| | - Eilhann E Kwon
- Department of Environment and Energy, Sejong University, Seoul 05006, Republic of Korea
| | - Amit Bhatnagar
- Department of Separation Science, LUT School of Engineering Science, LUT University, Sammonkatu 12, FI-50130, Mikkeli, Finland.
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Kselíková V, Singh A, Bialevich V, Čížková M, Bišová K. Improving microalgae for biotechnology - From genetics to synthetic biology - Moving forward but not there yet. Biotechnol Adv 2021; 58:107885. [PMID: 34906670 DOI: 10.1016/j.biotechadv.2021.107885] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 11/28/2021] [Accepted: 12/07/2021] [Indexed: 12/28/2022]
Abstract
Microalgae are a diverse group of photosynthetic organisms that can be exploited for the production of different compounds, ranging from crude biomass and biofuels to high value-added biochemicals and synthetic proteins. Traditionally, algal biotechnology relies on bioprospecting to identify new highly productive strains and more recently, on forward genetics to further enhance productivity. However, it has become clear that further improvements in algal productivity for biotechnology is impossible without combining traditional tools with the arising molecular genetics toolkit. We review recent advantages in developing high throughput screening methods, preparing genome-wide mutant libraries, and establishing genome editing techniques. We discuss how algae can be improved in terms of photosynthetic efficiency, biofuel and high value-added compound production. Finally, we critically evaluate developments over recent years and explore future potential in the field.
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Affiliation(s)
- Veronika Kselíková
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Cell Cycles of Algae, 379 81 Třeboň, Czech Republic; Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
| | - Anjali Singh
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Cell Cycles of Algae, 379 81 Třeboň, Czech Republic
| | - Vitali Bialevich
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Cell Cycles of Algae, 379 81 Třeboň, Czech Republic
| | - Mária Čížková
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Cell Cycles of Algae, 379 81 Třeboň, Czech Republic
| | - Kateřina Bišová
- Institute of Microbiology of the Czech Academy of Sciences, Centre Algatech, Laboratory of Cell Cycles of Algae, 379 81 Třeboň, Czech Republic.
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13
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Cecchin M, Jeong J, Son W, Kim M, Park S, Zuliani L, Cazzaniga S, Pompa A, Young Kang C, Bae S, Ballottari M, Jin E. LPA2 protein is involved in photosystem II assembly in Chlamydomonas reinhardtii. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:1648-1662. [PMID: 34218480 PMCID: PMC8518032 DOI: 10.1111/tpj.15405] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 06/23/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
Photosynthetic eukaryotes require the proper assembly of photosystem II (PSII) in order to strip electrons from water and fuel carbon fixation reactions. In Arabidopsis thaliana, one of the PSII subunits (CP43/PsbC) was suggested to be assembled into the PSII complex via its interaction with an auxiliary protein called Low PSII Accumulation 2 (LPA2). However, the original articles describing the role of LPA2 in PSII assembly have been retracted. To investigate the function of LPA2 in the model organism for green algae, Chlamydomonas reinhardtii, we generated knockout lpa2 mutants by using the CRISPR-Cas9 target-specific genome editing system. Biochemical analyses revealed the thylakoidal localization of LPA2 protein in the wild type (WT), whereas lpa2 mutants were characterized by a drastic reduction in the levels of D1, D2, CP47 and CP43 proteins. Consequently, reduced PSII supercomplex accumulation, chlorophyll content per cell, PSII quantum yield and photosynthetic oxygen evolution were measured in the lpa2 mutants, leading to the almost complete impairment of photoautotrophic growth. Pulse-chase experiments demonstrated that the absence of LPA2 protein caused reduced PSII assembly and reduced PSII turnover. Taken together, our data indicate that, in C. reinhardtii, LPA2 is required for PSII assembly and proper function.
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Affiliation(s)
- Michela Cecchin
- Dipartimento di BiotecnologieUniversità di VeronaStrada le Grazie 15Verona37134Italy
| | - Jooyeon Jeong
- Department of Life ScienceHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Woojae Son
- Department of ChemistryHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Minjae Kim
- Department of Life ScienceHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Seunghye Park
- Department of Life ScienceHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Luca Zuliani
- Dipartimento di BiotecnologieUniversità di VeronaStrada le Grazie 15Verona37134Italy
| | - Stefano Cazzaniga
- Dipartimento di BiotecnologieUniversità di VeronaStrada le Grazie 15Verona37134Italy
| | - Andrea Pompa
- Dipartimento di Scienze BiomolecolariUniversità degli studi di UrbinoVia Aurelio Saffi, 2Urbino61029Italy
- Istituto di Bioscienze e BiorisorseConsiglio Nazionale delle RicercheVia Madonna Alta, 130Perugia06128Italy
| | - Chan Young Kang
- Department of ChemistryHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Sangsu Bae
- Department of ChemistryHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Matteo Ballottari
- Dipartimento di BiotecnologieUniversità di VeronaStrada le Grazie 15Verona37134Italy
| | - EonSeon Jin
- Department of Life ScienceHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
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14
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Microalgae with a truncated light-harvesting antenna to maximize photosynthetic efficiency and biomass productivity: Recent advances and current challenges. Process Biochem 2021. [DOI: 10.1016/j.procbio.2021.03.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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15
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Nymark M, Grønbech Hafskjold MC, Volpe C, Fonseca DDM, Sharma A, Tsirvouli E, Serif M, Winge P, Finazzi G, Bones AM. Functional studies of CpSRP54 in diatoms show that the mechanism of thylakoid protein insertion differs from that in plants and green algae. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 106:113-132. [PMID: 33372269 DOI: 10.1111/tpj.15149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 12/16/2020] [Accepted: 12/22/2020] [Indexed: 06/12/2023]
Abstract
The chloroplast signal recognition particle 54 kDa (CpSRP54) protein is a member of the CpSRP pathway known to target proteins to thylakoid membranes in plants and green algae. Loss of CpSRP54 in the marine diatom Phaeodactylum tricornutum lowers the accumulation of a selection of chloroplast-encoded subunits of photosynthetic complexes, indicating a role in the co-translational part of the CpSRP pathway. In contrast to plants and green algae, absence of CpSRP54 does not have a negative effect on the content of light-harvesting antenna complex proteins and pigments in P. tricornutum, indicating that the diatom CpSRP54 protein has not evolved to function in the post-translational part of the CpSRP pathway. Cpsrp54 KO mutants display altered photophysiological responses, with a stronger induction of photoprotective mechanisms and lower growth rates compared to wild type when exposed to increased light intensities. Nonetheless, their phenotype is relatively mild, thanks to the activation of mechanisms alleviating the loss of CpSRP54, involving upregulation of chaperones. We conclude that plants, green algae, and diatoms have evolved differences in the pathways for co-translational and post-translational insertion of proteins into the thylakoid membranes.
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Affiliation(s)
- Marianne Nymark
- Department of Biology, Norwegian University of Science and Technology, Trondheim, N-7491, Norway
| | - Marthe Caroline Grønbech Hafskjold
- Department of Biology, Norwegian University of Science and Technology, Trondheim, N-7491, Norway
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology, Trondheim, N-7491, Norway
| | - Charlotte Volpe
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology, Trondheim, N-7491, Norway
| | - Davi de Miranda Fonseca
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, NTNU, Trondheim, N-7491, Norway
- Proteomics and Modomics Experimental Core Facility (PROMEC), NTNU and Central Administration, St Olavs Hospital, The University Hospital in Trondheim, Trondheim, Norway
| | - Animesh Sharma
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, NTNU, Trondheim, N-7491, Norway
- Proteomics and Modomics Experimental Core Facility (PROMEC), NTNU and Central Administration, St Olavs Hospital, The University Hospital in Trondheim, Trondheim, Norway
| | - Eirini Tsirvouli
- Department of Biology, Norwegian University of Science and Technology, Trondheim, N-7491, Norway
| | - Manuel Serif
- Department of Biology, Norwegian University of Science and Technology, Trondheim, N-7491, Norway
| | - Per Winge
- Department of Biology, Norwegian University of Science and Technology, Trondheim, N-7491, Norway
| | - Giovanni Finazzi
- Université Grenoble Alpes (UGA), Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, Centre National de la Recherche Scientifique (CNRS), Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), Interdisciplinary Research Institute of Grenoble (IRIG), CEA-Grenoble, Grenoble, 38000, France
| | - Atle Magnar Bones
- Department of Biology, Norwegian University of Science and Technology, Trondheim, N-7491, Norway
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Shi Y, He Y, Lv X, Wei Y, Zhang X, Xu X, Li L, Wu JL. Chloroplast SRP54s are Essential for Chloroplast Development in Rice. RICE (NEW YORK, N.Y.) 2020; 13:54. [PMID: 32761436 PMCID: PMC7410889 DOI: 10.1186/s12284-020-00415-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 07/29/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND The chloroplast signal recognition particle 54 (cpSRP54) is known for targeting the light-harvesting complex proteins to thylakoids and plays a critical role for chloroplast development in Arabidopsis, but little is known in rice. Here, we reported two homologous cpSRP54s that affect chloroplast development and plant survival in rice. RESULTS Two rice cpSRP54 homologues, OscpSRP54a and OscpSRP54b, were identified in present study. The defective OscpSRP54a (LOC_Os11g05552) was responsible for the pale green leaf phenotype of the viable pale green leaf 14 (pgl14) mutant. A single nucleotide substitution from G to A at the position 278, the first intron splicing site, was detected in LOC_Os11g05552 in pgl14. The wild type allele could rescue the mutant phenotype. Knockout lines of OscpSRP54b (LOC_Os11g05556) exhibited similar pale green phenotype to pgl14 with reduced chlorophyll contents and impaired chloroplast development, but showed apparently arrested-growth and died within 3 weeks. Both OscpSRP54a and OscpSRP54b were constitutively expressed mainly in shoots and leaves at the vegetative growth stage. Subcellular location indicated that both OscpSRP54a and OscpSRP54b were chloroplast-localized. Both OscpSRP54a and OscpSRP54b were able to interact with OscpSRP43, respectively. The transcript level of OscpSRP43 was significantly reduced while the transcript level of OscpSRP54b was apparently increased in pgl14. In contrast, the transcript levels of OscpSRP54a, OscpSRP43 and OscpSRP54b were all significantly decreased in OscpSRP54b knockout lines. CONCLUSION Our study demonstrated that both OscpSRP54a and OscpSRP54b were essential for normal chloroplast development by interacting with OscpSRP43 in rice. OscpSRP54a and OscpSRP54b might play distinct roles in transporting different chloroplast proteins into thylakoids through cpSRP-mediated pathway.
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Affiliation(s)
- Yongfeng Shi
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 China
| | - Yan He
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 China
| | - Xiangguang Lv
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 China
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Yanlin Wei
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 China
| | - Xiaobo Zhang
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 China
| | - Xia Xu
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 China
| | - Liangjian Li
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 China
| | - Jian-li Wu
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 310006 China
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Cecchin M, Berteotti S, Paltrinieri S, Vigliante I, Iadarola B, Giovannone B, Maffei ME, Delledonne M, Ballottari M. Improved lipid productivity in Nannochloropsis gaditana in nitrogen-replete conditions by selection of pale green mutants. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:78. [PMID: 32336989 PMCID: PMC7175523 DOI: 10.1186/s13068-020-01718-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 04/15/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Nannochloropsis gaditana is a photosynthetic unicellular microalgae considered one of the most interesting marine algae to produce biofuels and food additive due to its rapid growth rate and high lipid accumulation. Although microalgae are attractive platforms for solar energy bioconversion, the overall efficiency of photosynthesis is reduced due to the steep light gradient in photobioreactors. Moreover, accumulation of lipids in microalgae for biofuels production is usually induced in a two-phase cultivation process by nutrient starvation, with additional time and costs associated. In this work, a biotechnological approach was directed for the isolation of strains with improved light penetration in photobioreactor combined with increased lipids productivity. RESULTS Mutants of Nannochloropsis gaditana were obtained by chemical mutagenesis and screened for having both a reduced chlorophyll content per cell and increased affinity for Nile red, a fluorescent dye which binds to cellular lipid fraction. Accordingly, one mutant, called e8, was selected and characterized for having a 30% reduction of chlorophyll content per cell and an almost 80% increase of lipid productivity compared to WT in nutrient-replete conditions, with C16:0 and C18:0 fatty acids being more than doubled in the mutant. Whole-genome sequencing revealed mutations in 234 genes in e8 mutant among which there is a non-conservative mutation in the dgd1 synthase gene. This gene encodes for an enzyme involved in the biosynthesis of DGDG, one of the major lipids found in the thylakoid membrane and it is thus involved in chloroplast biogenesis. Lipid biosynthesis is strongly influenced by light availability in several microalgae species, including Nannochloropsis gaditana: reduced chlorophyll content per cell and more homogenous irradiance in photobioreactor is at the base for the increased lipid productivity observed in the e8 mutant. CONCLUSIONS The results herein obtained presents a promising strategy to produce algal biomass enriched in lipid fraction to be used for biofuel and biodiesel production in a single cultivation process, without the additional complexity of the nutrient starvation phase. Genome sequencing and identification of the mutations introduced in e8 mutant suggest possible genes responsible for the observed phenotypes, identifying putative target for future complementation and biotechnological application.
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Affiliation(s)
- Michela Cecchin
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada le Grazie 15, 37134 Verona, Italy
| | - Silvia Berteotti
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada le Grazie 15, 37134 Verona, Italy
| | - Stefania Paltrinieri
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada le Grazie 15, 37134 Verona, Italy
| | - Ivano Vigliante
- Dipartimento di Scienze della Vita e Biologia dei Sistemi, Unità di Fisiologia Vegetale, Università di Torino, Via Quarello 15/a, 10135 Turin, Italy
| | - Barbara Iadarola
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada le Grazie 15, 37134 Verona, Italy
| | - Barbara Giovannone
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada le Grazie 15, 37134 Verona, Italy
| | - Massimo E. Maffei
- Dipartimento di Scienze della Vita e Biologia dei Sistemi, Unità di Fisiologia Vegetale, Università di Torino, Via Quarello 15/a, 10135 Turin, Italy
| | - Massimo Delledonne
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada le Grazie 15, 37134 Verona, Italy
| | - Matteo Ballottari
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada le Grazie 15, 37134 Verona, Italy
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Kim J, Lee S, Baek K, Jin E. Site-Specific Gene Knock-Out and On-Site Heterologous Gene Overexpression in Chlamydomonas reinhardtii via a CRISPR-Cas9-Mediated Knock-in Method. FRONTIERS IN PLANT SCIENCE 2020; 11:306. [PMID: 32265959 PMCID: PMC7099044 DOI: 10.3389/fpls.2020.00306] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 03/03/2020] [Indexed: 05/27/2023]
Abstract
Chlamydomonas reinhardtii is being transformed from a model organism to an industrial organism for the production of pigments, fatty acids, and pharmaceuticals. Genetic modification has been used to increase the economic value of C. reinhardtii. However, low gene-editing efficiency and position-effects hinder the genetic improvement of this microorganism. Recently, site-specific double-stranded DNA cleavage using CRISPR-Cas9 system has been applied to regulate a metabolic pathway in C. reinhardtii. In this study, we proved that site-specific gene expression can be induced by CRISPR-Cas9-mediated double-strand cleavage and non-homologous end joining (NHEJ) mechanism. The CRISPR-Cas9-mediated knock-in method was adopted to improve gene-editing efficiency and express the reporter gene on the intended site. Knock-in was performed using a combination of ribonucleoprotein (RNP) complex and DNA fragment (antibiotics resistance gene). Gene-editing efficiency was improved via optimization of a component of RNP complex. We found that when the gene CrFTSY was targeted, the efficiency of obtaining the desired mutant by the knock-in method combined with antibiotic resistance was nearly 37%; 2.5 times higher than the previous reports. Additionally, insertion of a long DNA fragment (3.2 and 6.4 kb) and site-specific gene expression were analyzed. We demonstrated the knock-out phenotype of CrFTSY and on-site inserted gene expression of luciferase and mVenus at the same time. This result showed that CRISPR-Cas9-mediated knock-in can be used to express the gene of interest avoiding position-effects in C. reinhardtii. This report could provide a new perspective to the use of gene-editing. Furthermore, the technical improvements in genetic modification may accelerate the commercialization of C. reinhardtii.
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Affiliation(s)
| | | | | | - EonSeon Jin
- Department of Life Science, Research Institute for Natural Science, Hanyang University, Seoul, South Korea
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Park S, Nguyen THT, Jin E. Improving lipid production by strain development in microalgae: Strategies, challenges and perspectives. BIORESOURCE TECHNOLOGY 2019; 292:121953. [PMID: 31405625 DOI: 10.1016/j.biortech.2019.121953] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/31/2019] [Accepted: 08/01/2019] [Indexed: 05/16/2023]
Abstract
Over the past decade, the number of original articles and reviews presenting microalgae as a promising feedstock for biodiesel has increased tremendously. Many improvements of microalgae have been achieved through selection and strain development for industrial applications. However, the large-scale production of lipids for commercialization is not yet realistic because the production is still much more expensive than that of agricultural products. This review summarizes recent research on the induction of lipid biosynthesis in microalgae and the various strategies of genetic and metabolic engineering for enhancing lipid production. Strain engineering targets are proposed based on these strategies. To address current limitations of strain engineering for lipid production, this review provides insights on recent engineering strategies based on molecular tools and methods, and also discusses further perspectives.
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Affiliation(s)
- Seunghye Park
- Department of Life Science, Research Institute for Natural Sciences, Hanyang University, Seoul, Republic of Korea
| | - Thu Ha Thi Nguyen
- Department of Life Science, Research Institute for Natural Sciences, Hanyang University, Seoul, Republic of Korea
| | - EonSeon Jin
- Department of Life Science, Research Institute for Natural Sciences, Hanyang University, Seoul, Republic of Korea.
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20
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Ban S, Lin W, Luo Z, Luo J. Improving hydrogen production of Chlamydomonas reinhardtii by reducing chlorophyll content via atmospheric and room temperature plasma. BIORESOURCE TECHNOLOGY 2019; 275:425-429. [PMID: 30594343 DOI: 10.1016/j.biortech.2018.12.062] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 12/17/2018] [Accepted: 12/18/2018] [Indexed: 06/09/2023]
Abstract
Reduction of chlorophyll size has great advantages on improving the photosynthesis efficiency as well as the photolysis algal H2 production. To promote the H2 production, Chlamydomonas reinhardtii was mutated by atmospheric and room temperature plasma (ARTP). After the selection, an algal mutant was observed to have 1.8-5.2 times (28.5-84.1 mL L-1) and 2.7-3.1 times (356.5-405.2 mL L-1) higher H2 production than wild-type during the algal subcultures grown in pure and co-cultures, respectively. In comparison with wild-type alga, the mutant grew as lighter green colonies on agar plate, with about 2 times larger cell diameter and 5.3-6.1 times lower chlorophyll content per unit cell volume. Results from the comparative transcriptomic analysis indicated that most of the genes relating to photosynthesis (photosystem I, II, cytochrome b6/f complex, photosynthetic electron transport, and F-type ATPase) and LHC proteins were have higher expressions in mutant cells, suggesting the improvement of photosynthesis efficiency.
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Affiliation(s)
- Shidong Ban
- Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, PR China
| | - Weitie Lin
- Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, PR China.
| | - Zhiwei Luo
- Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, PR China
| | - Jianfei Luo
- Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, PR China.
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21
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Shin YS, Jeong J, Nguyen THT, Kim JYH, Jin E, Sim SJ. Targeted knockout of phospholipase A 2 to increase lipid productivity in Chlamydomonas reinhardtii for biodiesel production. BIORESOURCE TECHNOLOGY 2019; 271:368-374. [PMID: 30293032 DOI: 10.1016/j.biortech.2018.09.121] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 09/22/2018] [Accepted: 09/24/2018] [Indexed: 05/10/2023]
Abstract
Biofuel derived from microalgae have several advantages over other oleaginous crops, however, still needs to be improved with its cost aspect and can be achieved by developing of a strain with improved lipid productivity. In this study, the CRISPR-Cas9 system was incorporated to carry out a target-specific knockout of the phospholipase A2 gene in Chlamydomonas reinhardtii. The targeted gene encodes a key enzyme in the Lands cycle. As a result, the mutants showed a characteristic of increased diacylglycerol pool, followed by a higher accumulation of triacylglycerol without being significantly compensated with the cell growth. As a result, the overall lipid productivities of phospholipase A2 knockout mutants have increased by up to 64.25% (to 80.92 g L-1 d-1). This study can provide crucial information for the biodiesel industry.
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Affiliation(s)
- Ye Sol Shin
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seoungbuk-gu, Seoul 02841, Republic of Korea
| | - Jooyeon Jeong
- Department of Life Science and Research Institute for Natural Sciences, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Thu Ha Thi Nguyen
- Department of Life Science and Research Institute for Natural Sciences, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Jaoon Young Hwan Kim
- Convergence Research Division, National Marine Biodiversity Institute of Korea, Jangsan-ro 101beon-gil 75, Janghang-eup, Seocheon-gun, Chungcheongnam-do 33662, Republic of Korea
| | - EonSeon Jin
- Department of Life Science and Research Institute for Natural Sciences, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Sang Jun Sim
- Department of Chemical and Biological Engineering, Korea University, 145, Anam-ro, Seoungbuk-gu, Seoul 02841, Republic of Korea.
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Benedetti M, Vecchi V, Barera S, Dall’Osto L. Biomass from microalgae: the potential of domestication towards sustainable biofactories. Microb Cell Fact 2018; 17:173. [PMID: 30414618 PMCID: PMC6230293 DOI: 10.1186/s12934-018-1019-3] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Accepted: 10/31/2018] [Indexed: 12/22/2022] Open
Abstract
Interest in bulk biomass from microalgae, for the extraction of high-value nutraceuticals, bio-products, animal feed and as a source of renewable fuels, is high. Advantages of microalgal vs. plant biomass production include higher yield, use of non-arable land, recovery of nutrients from wastewater, efficient carbon capture and faster development of new domesticated strains. Moreover, adaptation to a wide range of environmental conditions evolved a great genetic diversity within this polyphyletic group, making microalgae a rich source of interesting and useful metabolites. Microalgae have the potential to satisfy many global demands; however, realization of this potential requires a decrease of the current production costs. Average productivity of the most common industrial strains is far lower than maximal theoretical estimations, suggesting that identification of factors limiting biomass yield and removing bottlenecks are pivotal in domestication strategies aimed to make algal-derived bio-products profitable on the industrial scale. In particular, the light-to-biomass conversion efficiency represents a major constraint to finally fill the gap between theoretical and industrial productivity. In this respect, recent results suggest that significant yield enhancement is feasible. Full realization of this potential requires further advances in cultivation techniques, together with genetic manipulation of both algal physiology and metabolic networks, to maximize the efficiency with which solar energy is converted into biomass and bio-products. In this review, we draft the molecular events of photosynthesis which regulate the conversion of light into biomass, and discuss how these can be targeted to enhance productivity through mutagenesis, strain selection or genetic engineering. We outline major successes reached, and promising strategies to achieving significant contributions to future microalgae-based biotechnology.
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Affiliation(s)
- Manuel Benedetti
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Valeria Vecchi
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Simone Barera
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Luca Dall’Osto
- Dipartimento di Biotecnologie, Università di Verona, Strada Le Grazie 15, 37134 Verona, Italy
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Kirst H, Shen Y, Vamvaka E, Betterle N, Xu D, Warek U, Strickland JA, Melis A. Downregulation of the CpSRP43 gene expression confers a truncated light-harvesting antenna (TLA) and enhances biomass and leaf-to-stem ratio in Nicotiana tabacum canopies. PLANTA 2018; 248:139-154. [PMID: 29623472 DOI: 10.1007/s00425-018-2889-7] [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: 01/08/2018] [Accepted: 03/29/2018] [Indexed: 05/13/2023]
Abstract
MAIN CONCLUSION Downregulation in the expression of the signal recognition particle 43 (SRP43) gene in tobacco conferred a truncated photosynthetic light-harvesting antenna (TLA property), and resulted in plants with a greater leaf-to-stem ratio, improved photosynthetic productivity and canopy biomass accumulation under high-density cultivation conditions. Evolution of sizable arrays of light-harvesting antennae in all photosynthetic systems confers a survival advantage for the organism in the wild, where sunlight is often the growth-limiting factor. In crop monocultures, however, this property is strongly counterproductive, when growth takes place under direct and excess sunlight. The large arrays of light-harvesting antennae in crop plants cause the surface of the canopies to over-absorb solar irradiance, far in excess of what is needed to saturate photosynthesis and forcing them to engage in wasteful dissipation of the excess energy. Evidence in this work showed that downregulation by RNA-interference approaches of the Nicotiana tabacum signal recognition particle 43 (SRP43), a nuclear gene encoding a chloroplast-localized component of the photosynthetic light-harvesting assembly pathway, caused a decrease in the light-harvesting antenna size of the photosystems, a corresponding increase in the photosynthetic productivity of chlorophyll in the leaves, and improved tobacco plant canopy biomass accumulation under high-density cultivation conditions. Importantly, the resulting TLA transgenic plants had a substantially greater leaf-to-stem biomass ratio, compared to those of the wild type, grown under identical agronomic conditions. The results are discussed in terms of the potential benefit that could accrue to agriculture upon application of the TLA-technology to crop plants, entailing higher density planting with plants having a greater biomass and leaf-to-stem ratio, translating into greater crop yields per plant with canopies in a novel agronomic configuration.
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Affiliation(s)
- Henning Kirst
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720-3102, USA
| | - Yanxin Shen
- Biotechnology Division, Altria Client Services, Richmond, VA, 23219, USA
| | - Evangelia Vamvaka
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720-3102, USA
| | - Nico Betterle
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720-3102, USA
| | - Dongmei Xu
- Biotechnology Division, Altria Client Services, Richmond, VA, 23219, USA
| | - Ujwala Warek
- Biotechnology Division, Altria Client Services, Richmond, VA, 23219, USA
| | - James A Strickland
- Biotechnology Division, Altria Client Services, Richmond, VA, 23219, USA
| | - Anastasios Melis
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, 94720-3102, USA.
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24
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Jeong J, Baek K, Yu J, Kirst H, Betterle N, Shin W, Bae S, Melis A, Jin E. Deletion of the chloroplast LTD protein impedes LHCI import and PSI-LHCI assembly in Chlamydomonas reinhardtii. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:1147-1158. [PMID: 29300952 PMCID: PMC6018721 DOI: 10.1093/jxb/erx457] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 12/12/2017] [Indexed: 05/26/2023]
Abstract
Nuclear-encoded light-harvesting chlorophyll- and carotenoid-binding proteins (LHCPs) are imported into the chloroplast and transported across the stroma to thylakoid membrane assembly sites by the chloroplast signal recognition particle (CpSRP) pathway. The LHCP translocation defect (LTD) protein is essential for the delivery of imported LHCPs to the CpSRP pathway in Arabidopsis. However, the function of the LTD protein in Chlamydomonas reinhardtii has not been investigated. Here, we generated a C. reinhardtii ltd (Crltd) knockout mutant by using CRISPR-Cas9, a new target-specific knockout technology. The Crltd1 mutant showed a low chlorophyll content per cell with an unusual increase in appressed thylakoid membranes and enlarged cytosolic vacuoles. Profiling of thylakoid membrane proteins in the Crltd1 mutant showed a more severe reduction in the levels of photosystem I (PSI) core proteins and absence of functional LHCI compared with those of photosystem II, resulting in a much smaller PSI pool size and diminished chlorophyll antenna size. The lack of CrLTD did not prevent photoautotrophic growth of the cells. These results are substantially different from those for Arabidopsis ltd null mutant, indicating LTD function in LHCP delivery and PSI assembly may not be as stringent in C. reinhardtii as it is in higher plants.
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Affiliation(s)
- Jooyeon Jeong
- Department of Life Science and Research Institute for Natural Sciences, Hanyang University, Seoul, Korea
| | - Kwangryul Baek
- Department of Life Science and Research Institute for Natural Sciences, Hanyang University, Seoul, Korea
| | - Jihyeon Yu
- School of Biological Sciences, Seoul National University, Seoul, Korea
| | - Henning Kirst
- Department of Plant and Microbial Biology, University of California, Berkeley, California USA
| | - Nico Betterle
- Department of Plant and Microbial Biology, University of California, Berkeley, California USA
| | - Woongghi Shin
- Department of Biology, Chungnam National University, Daejeon, Korea
| | - Sangsu Bae
- Department of Chemistry, Hanyang University, Seoul, Korea
| | - Anastasios Melis
- Department of Plant and Microbial Biology, University of California, Berkeley, California USA
| | - EonSeon Jin
- Department of Life Science and Research Institute for Natural Sciences, Hanyang University, Seoul, Korea
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25
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Complementation of a mutation in CpSRP43 causing partial truncation of light-harvesting chlorophyll antenna in Chlorella vulgaris. Sci Rep 2017; 7:17929. [PMID: 29263352 PMCID: PMC5738337 DOI: 10.1038/s41598-017-18221-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 12/07/2017] [Indexed: 12/17/2022] Open
Abstract
Photosynthesis of microalgae enables conversion of light energy into chemical energy to produce biomass and biomaterials. However, the efficiency of this process must be enhanced, and truncation of light-harvesting complex (LHC) has been suggested to improve photosynthetic efficiency. We reported an EMS-induced mutant (E5) showing partially reduced LHC in Chlorella vulgaris. We determined the mutation by sequencing the whole genome of WT and E5. Augustus gene prediction was used for determining CDS, and non-synonymous changes in E5 were screened. Among these, we found a point mutation (T to A) in a gene homologous to chloroplast signal recognition particle 43 kDa (CpSRP43). The point mutation changed the 102nd valine to glutamic acid (V102E) located in the first chromodomain. Phylogenetic analyses of CpSRP43 revealed that this amino acid was valine or isoleucine in microalgae and plants, suggesting important functions. Transformation of E5 with WT CpSRP43 showed varying degrees of complementation, which was demonstrated by partial recovery of the LHCII proteins to the WT level, and partially restored photosynthetic pigments, photosynthetic ETR, NPQ, and growth, indicating that the V102E mutation was responsible for the reduced LHC in E5.
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Ziehe D, Dünschede B, Schünemann D. From bacteria to chloroplasts: evolution of the chloroplast SRP system. Biol Chem 2017; 398:653-661. [PMID: 28076289 DOI: 10.1515/hsz-2016-0292] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 01/04/2017] [Indexed: 02/02/2023]
Abstract
Chloroplasts derive from a prokaryotic symbiont that lost most of its genes during evolution. As a result, the great majority of chloroplast proteins are encoded in the nucleus and are posttranslationally imported into the organelle. The chloroplast genome encodes only a few proteins. These include several multispan thylakoid membrane proteins which are synthesized on thylakoid-bound ribosomes and cotranslationally inserted into the membrane. During evolution, ancient prokaryotic targeting machineries were adapted and combined with novel targeting mechanisms to facilitate post- and cotranslational protein transport in chloroplasts. This review focusses on the chloroplast signal recognition particle (cpSRP) protein transport system, which has been intensively studied in higher plants. The cpSRP system derived from the prokaryotic SRP pathway, which mediates the cotranslational protein transport to the bacterial plasma membrane. Chloroplasts contain homologs of several components of the bacterial SRP system. The function of these conserved components in post- and/or cotranslational protein transport and chloroplast-specific modifications of these transport mechanisms are described. Furthermore, recent studies of cpSRP systems in algae and lower plants are summarized and their impact on understanding the evolution of the cpSRP system are discussed.
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Affiliation(s)
- Dominik Ziehe
- Molecular Biology of Plant Organelles, Ruhr University Bochum, Universitätsstraße 150, D-44780 Bochum
| | - Beatrix Dünschede
- Molecular Biology of Plant Organelles, Ruhr University Bochum, Universitätsstraße 150, D-44780 Bochum
| | - Danja Schünemann
- Molecular Biology of Plant Organelles, Ruhr University Bochum, Universitätsstraße 150, D-44780 Bochum
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Abstract
Zeaxanthin is a xanthophyll pigment that is regarded as one of the best carotenoids for the prevention and treatment of degenerative diseases. In the worldwide natural products market, consumers prefer pigments that have been produced from biological sources. In this study, a Dunaliella tertiolecta strain that has 10–15% higher cellular zeaxanthin content than the parent strain (zea1), was obtained by random mutagenesis using ethyl methanesulfonate (EMS) as a mutagen. This mutant, mp3, was grown under various salinities and light intensities to optimize culture conditions for zeaxanthin production. The highest cellular zeaxanthin content was observed at 1.5 M NaCl and 65–85 μmol photons·m−2·s−1, and the highest daily zeaxanthin productivity was observed at 0.6 M NaCl and 140–160 μmol photons·m−2·s−1. The maximal yield of zeaxanthin from mp3 in fed-batch culture was 8 mg·L−1, which was obtained at 0.6 M NaCl and 140–160 μmol photons·m−2·s−1. These results suggest that random mutagenesis with EMS is useful for generating D. tertiolecta strains with increased zeaxanthin content, and also suggest optimal culture conditions for the enhancement of biomass and zeaxanthin production by the zeaxanthin accumulating mutant strains.
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