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Wang H, Qin L, Qi W, Elshobary M, Wang W, Feng P, Wang Z, Zhu S. Harmony in detoxification: Microalgae unleashing the potential of lignocellulosic pretreatment wastewater for resource utilization. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:171888. [PMID: 38531442 DOI: 10.1016/j.scitotenv.2024.171888] [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: 12/22/2023] [Revised: 02/28/2024] [Accepted: 03/20/2024] [Indexed: 03/28/2024]
Abstract
Lignocellulosic biomass is a pivotal renewable resource in biorefinery process, requiring pretreatment, primarily chemical pretreatment, for effective depolymerization and subsequent transformation. This process yields solid residue for saccharification and lignocellulosic pretreatment wastewater (LPW), which comprises sugars and inhibitors such as phenols and furans. This study explored the microalgal capacity to treat LPW, focusing on two key hydrolysate inhibitors: furfural and vanillin, which impact the growth of six green microalgae. Chlorella sorokiniana exhibited higher tolerance to furfural and vanillin. However, both inhibitors hindered the growth of C. sorokiniana and disrupted algal photosynthetic system, with vanillin displaying superior inhibition. A synergistic inhibitory effect (Q < 0.85) was observed with furfural and vanillin on algal growth. Furfural transformation to low-toxic furfuryl alcohol was rapid, yet the addition of vanillin hindered this process. Vanillin stimulated carbohydrate accumulation, with 50.48 % observed in the 0.1 g/L furfural + 0.1 g/L vanillin group. Additionally, vanillin enhanced the accumulation of C16: 0 and C18: 2, reaching 21.71 % and 40.36 %, respectively, with 0.1 g/L vanillin. This study proposed a microalgae-based detoxification and resource utilization approach for LPW, enhancing the comprehensive utilization of lignocellulosic components. The observed biomass modifications also suggested potential applications for biofuel production, contributing to the evolving landscape of sustainable biorefinery processes.
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Affiliation(s)
- Huiying Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China; University of Science and Technology of China, Hefei 230026, PR China
| | - Lei Qin
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China.
| | - Wei Qi
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China
| | - Mostafa Elshobary
- Botany and Microbiology Department, Faculty of Science, Tanta University, Tanta 31527, Egypt
| | - Wen Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China
| | - Pingzhong Feng
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China
| | - Zhongming Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China
| | - Shunni Zhu
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, PR China.
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Wang X, He GH, Wang ZY, Xu HY, Mou JH, Qin ZH, Lin CSK, Yang WD, Zhang Y, Li HY. Purple acid phosphatase promoted hydrolysis of organophosphate pesticides in microalgae. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2024; 18:100318. [PMID: 37860829 PMCID: PMC10582367 DOI: 10.1016/j.ese.2023.100318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 08/24/2023] [Accepted: 09/13/2023] [Indexed: 10/21/2023]
Abstract
When organophosphate pesticides (OPs) are not used and handled in accordance with the current rules and standards, it results in serious threats to the aquatic environment and human health. Phaeodactylum tricornutum is a prospective microalgae-based system for pollutant removal and carbon sequestration. Genetically engineered P. tricornutum, designated as the OE line (endogenously expressing purple acid phosphatase 1 [PAP1]), can utilize organic phosphorus for cellular metabolism. However, the competencies and mechanisms of the microalgae-based system (namely the OE line of P. tricornutum) for metabolizing OPs remain to be addressed. In this study, the OE line exhibited the effective biodegradation competencies of 72.12% and 68.2% for 30 mg L-1 of dichlorvos and 50 mg L-1 of glyphosate, accompanied by synergistic accumulations of biomass (0.91 and 0.95 g L-1) and lipids (32.71% and 32.08%), respectively. Furthermore, the biodiesel properties of the lipids from the OE line manifested a high potential as an alternative feedstock for microalgae-based biofuel production. A plausible mechanism of OPs biodegraded by overexpressed PAP1 is that sufficient inorganic P for adenosine triphosphate and concurrent carbon flux for the reduced form of nicotinamide adenine dinucleotide phosphate biosynthesis, which improved the OP tolerance and biodegradation competencies by regulating the antioxidant system, delaying programmed cell death and accumulating lipids via the upregulation of related genes. To sum up, this study demonstrates a potential strategy using a genetically engineered strain of P. tricornutum to remove high concentrations of OPs with the simultaneous production of biomass and biofuels, which might provide novel insights for microalgae-based pollutant biodegradation.
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Affiliation(s)
- Xiang Wang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Guo-Hui He
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Zhen-Yao Wang
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Hui-Ying Xu
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Jin-Hua Mou
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 510000, China
| | - Zi-Hao Qin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 510000, China
| | - Carol Sze Ki Lin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong
| | - Wei-Dong Yang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Yalei Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Hong-Ye Li
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
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You L, Połońska A, Jasieniecka-Gazarkiewicz K, Richard F, Jouhet J, Maréchal E, Banaś A, Hu H, Pan Y, Hao X, Jin H, Allen AE, Amato A, Gong Y. Two plastidial lysophosphatidic acid acyltransferases differentially mediate the biosynthesis of membrane lipids and triacylglycerols in Phaeodactylum tricornutum. THE NEW PHYTOLOGIST 2024; 241:1543-1558. [PMID: 38031462 DOI: 10.1111/nph.19434] [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: 06/15/2023] [Accepted: 11/06/2023] [Indexed: 12/01/2023]
Abstract
Lysophosphatidic acid acyltransferases (LPAATs) catalyze the formation of phosphatidic acid (PA), a central metabolite in both prokaryotic and eukaryotic organisms for glycerolipid biosynthesis. Phaeodactylum tricornutum contains at least two plastid-localized LPAATs (ptATS2a and ptATS2b), but their roles in lipid synthesis remain unknown. Both ptATS2a and ptATS2b could complement the high temperature sensitivity of the bacterial plsC mutant deficient in LPAAT. In vitro enzyme assays showed that they prefer lysophosphatidic acid over other lysophospholipids. ptATS2a is localized in the plastid inner envelope membrane and CRISPR/Cas9-generated ptATS2a mutants showed compromised cell growth, significantly changed plastid and extra-plastidial membrane lipids at nitrogen-replete condition and reduced triacylglycerols (TAGs) under nitrogen-depleted condition. ptATS2b is localized in thylakoid membranes and its knockout led to reduced growth rate and TAG content but slightly altered molecular composition of membrane lipids. The changes in glycerolipid profiles are consistent with the role of both LPAATs in the sn-2 acylation of sn-1-acyl-glycerol-3-phosphate substrates harboring 20:5 at the sn-1 position. Our findings suggest that both LPAATs are important for membrane lipids and TAG biosynthesis in P. tricornutum and further highlight that 20:5-Lyso-PA is likely involved in the massive import of 20:5 back to the plastid to feed plastid glycerolipid syntheses.
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Affiliation(s)
- Lingjie You
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, 430062, China
| | - Ada Połońska
- Intercollegiate Faculty of Biotechnology of UG and MUG, Gdansk, 80-307, Poland
| | | | - Fabien Richard
- Laboratoire de Physiologie Cellulaire et Végétale, Centre National de la Recherche Scientifique, Commissariat à l'Energie Atomique et aux Energies Alternatives, INRAE, Université Grenoble Alpes, Unité mixte de recherche 5168, IRIG, CEA Grenoble, F-38041, Grenoble, France
| | - Juliette Jouhet
- Laboratoire de Physiologie Cellulaire et Végétale, Centre National de la Recherche Scientifique, Commissariat à l'Energie Atomique et aux Energies Alternatives, INRAE, Université Grenoble Alpes, Unité mixte de recherche 5168, IRIG, CEA Grenoble, F-38041, Grenoble, France
| | - Eric Maréchal
- Laboratoire de Physiologie Cellulaire et Végétale, Centre National de la Recherche Scientifique, Commissariat à l'Energie Atomique et aux Energies Alternatives, INRAE, Université Grenoble Alpes, Unité mixte de recherche 5168, IRIG, CEA Grenoble, F-38041, Grenoble, France
| | - Antoni Banaś
- Intercollegiate Faculty of Biotechnology of UG and MUG, Gdansk, 80-307, Poland
| | - Hanhua Hu
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Yufang Pan
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Xiahui Hao
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, 430062, China
| | - Hu Jin
- Center for Microalgal Biotechnology and Biofuels, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Andrew E Allen
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, 92093, USA
- J. Craig Venter Institute, 4120 Capricorn Lane, La Jolla, CA, 92037, USA
| | - Alberto Amato
- Laboratoire de Physiologie Cellulaire et Végétale, Centre National de la Recherche Scientifique, Commissariat à l'Energie Atomique et aux Energies Alternatives, INRAE, Université Grenoble Alpes, Unité mixte de recherche 5168, IRIG, CEA Grenoble, F-38041, Grenoble, France
| | - Yangmin Gong
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, 430062, China
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, Wuhan, 430062, China
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Wang M, Ye X, Bi H, Shen Z. Microalgae biofuels: illuminating the path to a sustainable future amidst challenges and opportunities. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:10. [PMID: 38254224 PMCID: PMC10804497 DOI: 10.1186/s13068-024-02461-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 01/11/2024] [Indexed: 01/24/2024]
Abstract
The development of microalgal biofuels is of significant importance in advancing the energy transition, alleviating food pressure, preserving the natural environment, and addressing climate change. Numerous countries and regions across the globe have conducted extensive research and strategic planning on microalgal bioenergy, investing significant funds and manpower into this field. However, the microalgae biofuel industry has faced a downturn due to the constraints of high costs. In the past decade, with the development of new strains, technologies, and equipment, the feasibility of large-scale production of microalgae biofuel should be re-evaluated. Here, we have gathered research results from the past decade regarding microalgae biofuel production, providing insights into the opportunities and challenges faced by this industry from the perspectives of microalgae selection, modification, and cultivation. In this review, we suggest that highly adaptable microalgae are the preferred choice for large-scale biofuel production, especially strains that can utilize high concentrations of inorganic carbon sources and possess stress resistance. The use of omics technologies and genetic editing has greatly enhanced lipid accumulation in microalgae. However, the associated risks have constrained the feasibility of large-scale outdoor cultivation. Therefore, the relatively controllable cultivation method of photobioreactors (PBRs) has made it the mainstream approach for microalgae biofuel production. Moreover, adjusting the performance and parameters of PBRs can also enhance lipid accumulation in microalgae. In the future, given the relentless escalation in demand for sustainable energy sources, microalgae biofuels should be deemed a pivotal constituent of national energy planning, particularly in the case of China. The advancement of synthetic biology helps reduce the risks associated with genetically modified (GM) microalgae and enhances the economic viability of their biofuel production.
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Affiliation(s)
- Min Wang
- Institute of Agricultural Remote Sensing and Information, Heilongjiang Academy of Agricultural Sciences, Harbin, 150086, China.
| | - Xiaoxue Ye
- Sanya Research Institute of Chinese Academy of Tropical Agricultural Sciences, Sanya, 572025, China
| | - Hongwen Bi
- Institute of Agricultural Remote Sensing and Information, Heilongjiang Academy of Agricultural Sciences, Harbin, 150086, China
| | - Zhongbao Shen
- Grass and Science Institute of Heilongjiang Academy of Agricultural Sciences, Harbin, 150086, China.
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Peña-Castro JM, Muñoz-Páez KM, Robledo-Narvaez PN, Vázquez-Núñez E. Engineering the Metabolic Landscape of Microorganisms for Lignocellulosic Conversion. Microorganisms 2023; 11:2197. [PMID: 37764041 PMCID: PMC10535843 DOI: 10.3390/microorganisms11092197] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/16/2023] [Accepted: 08/18/2023] [Indexed: 09/29/2023] Open
Abstract
Bacteria and yeast are being intensively used to produce biofuels and high-added-value products by using plant biomass derivatives as substrates. The number of microorganisms available for industrial processes is increasing thanks to biotechnological improvements to enhance their productivity and yield through microbial metabolic engineering and laboratory evolution. This is allowing the traditional industrial processes for biofuel production, which included multiple steps, to be improved through the consolidation of single-step processes, reducing the time of the global process, and increasing the yield and operational conditions in terms of the desired products. Engineered microorganisms are now capable of using feedstocks that they were unable to process before their modification, opening broader possibilities for establishing new markets in places where biomass is available. This review discusses metabolic engineering approaches that have been used to improve the microbial processing of biomass to convert the plant feedstock into fuels. Metabolically engineered microorganisms (MEMs) such as bacteria, yeasts, and microalgae are described, highlighting their performance and the biotechnological tools that were used to modify them. Finally, some examples of patents related to the MEMs are mentioned in order to contextualize their current industrial use.
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Affiliation(s)
- Julián Mario Peña-Castro
- Centro de Investigaciones Científicas, Instituto de Biotecnología, Universidad del Papaloapan, Tuxtepec 68301, Oaxaca, Mexico;
| | - Karla M. Muñoz-Páez
- CONAHCYT—Instituto de Ingeniería, Unidad Académica Juriquilla, Universidad Nacional Autónoma de México, Queretaro 76230, Queretaro, Mexico;
| | | | - Edgar Vázquez-Núñez
- Grupo de Investigación Sobre Aplicaciones Nano y Bio Tecnológicas para la Sostenibilidad (NanoBioTS), Departamento de Ingenierías Química, Electrónica y Biomédica, División de Ciencias e Ingenierías, Universidad de Guanajuato, Lomas del Bosque 103, Lomas del Campestre, León 37150, Guanajuato, Mexico
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Sun H, Gao Z, Zhang L, Wang X, Gao M, Wang Q. A comprehensive review on microbial lipid production from wastes: research updates and tendencies. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:79654-79675. [PMID: 37328718 DOI: 10.1007/s11356-023-28123-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 06/01/2023] [Indexed: 06/18/2023]
Abstract
Microbial lipids have recently attracted attention as an intriguing alternative for the biodiesel and oleochemical industries to achieve sustainable energy generation. However, large-scale lipid production remains limited due to the high processing costs. As multiple variables affect lipid synthesis, an up-to-date overview that will benefit researchers studying microbial lipids is necessary. In this review, the most studied keywords from bibliometric studies are first reviewed. Based on the results, the hot topics in the field were identified to be associated with microbiology studies that aim to enhance lipid synthesis and reduce production costs, focusing on the biological and metabolic engineering involved. The research updates and tendencies of microbial lipids were then analyzed in depth. In particular, feedstock and associated microbes, as well as feedstock and corresponding products, were analyzed in detail. Strategies for lipid biomass enhancement were also discussed, including feedstock adoption, value-added product synthesis, selection of oleaginous microbes, cultivation mode optimization, and metabolic engineering strategies. Finally, the environmental implications of microbial lipid production and possible research directions were presented.
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Affiliation(s)
- Haishu Sun
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
- Shunde Innovation School, University of Science and Technology Beijing, Foshan, 528399, China
| | - Zhen Gao
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Lirong Zhang
- Tianjin College, University of Science and Technology, Beijing, Tianjin, 301811, China
| | - Xiaona Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
- Shunde Innovation School, University of Science and Technology Beijing, Foshan, 528399, China.
| | - Ming Gao
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Qunhui Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
- Tianjin College, University of Science and Technology, Beijing, Tianjin, 301811, China
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Song J, Zhao H, Zhang L, Li Z, Han J, Zhou C, Xu J, Li X, Yan X. The Heat Shock Transcription Factor PtHSF1 Mediates Triacylglycerol and Fucoxanthin Synthesis by Regulating the Expression of GPAT3 and DXS in Phaeodactylum tricornutum. PLANT & CELL PHYSIOLOGY 2023; 64:622-636. [PMID: 36947404 DOI: 10.1093/pcp/pcad023] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 01/31/2023] [Accepted: 03/21/2023] [Indexed: 06/16/2023]
Abstract
In addition to being important primary productive forces in marine ecosystems, diatoms are also rich in bioactive substances such as triacylglycerol and fucoxanthin. However, little is known about the transcriptional mechanisms underlying the biosynthesis of these substances. In this study, we found that the heat shock transcription factor PtHSF1 positively regulated the synthesis of triacylglycerol and fucoxanthin in Phaeodactylum tricornutum. Overexpression of PtHSF1 could increase the contents of triacylglycerol and fucoxanthin and upregulate key enzyme genes involved in the triacylglycerol and fucoxanthin biosynthesis pathways. On the other hand, gene silencing of PtHSF1 reduced the contents of triacylglycerol and fucoxanthin and the expression of the key enzyme genes involved in the triacylglycerol and fucoxanthin biosynthesis pathways. Further biochemical analysis revealed that PtHSF1 upregulated glycerol-2-phosphate acyltransferase 3 (GPAT3) and 1-deoxy-d-xylulose 5-phosphate synthase (DXS) by directly binding to their promoters, while genetic analysis demonstrated that PtHSF1 acted upstream of GPAT3 and DXS to regulate triacylglycerol and fucoxanthin synthesis. Therefore, in addition to elucidating the regulation mechanisms underlying PtHSF1-mediated triacylglycerol and fucoxanthin synthesis, this study also provided a candidate target for metabolic engineering of triacylglycerol and fucoxanthin in P. tricornutum.
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Affiliation(s)
- Jianquan Song
- School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Hejing Zhao
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
| | - Linxin Zhang
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
| | - Zheng Li
- School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Jichang Han
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
| | - Chengxu Zhou
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
| | - Jilin Xu
- School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Xiaohui Li
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315211, China
| | - Xiaojun Yan
- School of Marine Sciences, Ningbo University, Ningbo 315211, China
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Murison V, Hérault J, Schoefs B, Marchand J, Ulmann L. Bioinformatics-Based Screening Approach for the Identification and Characterization of Lipolytic Enzymes from the Marine Diatom Phaeodactylum tricornutum. Mar Drugs 2023; 21:md21020125. [PMID: 36827166 PMCID: PMC9964374 DOI: 10.3390/md21020125] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 02/13/2023] [Accepted: 02/14/2023] [Indexed: 02/17/2023] Open
Abstract
Oleaginous diatoms accumulate lipids of biotechnological interest when exposed to nutrient stress conditions such as nitrogen starvation. While accumulation mechanisms are well-known and have been engineered to improve lipid production, degradation mechanisms remain poorly investigated in diatoms. Identifying lipid-degrading enzymes is the initial step to understanding the catabolic processes. In this study, an in silico screening of the genome of Phaeodactylum tricornutum led to the identification of 57 putative triacylglycerol lipases (EC 3.1.1.3) grouped in 4 families. Further analysis revealed the presence of conserved domains and catalytic residues of lipases. Physico-chemical characteristics and subcellular localization predictions highlighted that a majority of these putative proteins are hydrophilic and cytosolic, suggesting they could be recruited to lipid droplets directly from the cytosol. Among the 57 identified putative proteins, three lipases were identified as possibly involved in lipophagy due to a potential vacuolar localization. The expression of the mRNA corresponding to the 57 proteins was then searched in 3 transcriptomic datasets obtained under nitrogen starvation. Nine genes were highly regulated and were considered as encoding enzymes with a probable important function in lipid catabolism. A tertiary structure prediction of these nine candidates yielded eight functional 3D models. Among those, two downregulated enzymes, Phatr3_J54974 and Phatr3_EG00720, were highlighted as good targets for future functional genomics and purification studies to investigate their role in lipid degradation.
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Affiliation(s)
- Victor Murison
- BiOSSE, Biology of Organisms: Stress, Health, Environment, Département Génie Biologique, Institut Universitaire de Technologie, Le Mans Université, F-53020 Laval, France
| | - Josiane Hérault
- BiOSSE, Biology of Organisms: Stress, Health, Environment, Département Génie Biologique, Institut Universitaire de Technologie, Le Mans Université, F-53020 Laval, France
| | - Benoît Schoefs
- BiOSSE, Biology of Organisms: Stress, Health, Environment, UFR Sciences et Techniques, Le Mans Université, F-72085 Le Mans, France
| | - Justine Marchand
- BiOSSE, Biology of Organisms: Stress, Health, Environment, UFR Sciences et Techniques, Le Mans Université, F-72085 Le Mans, France
| | - Lionel Ulmann
- BiOSSE, Biology of Organisms: Stress, Health, Environment, Département Génie Biologique, Institut Universitaire de Technologie, Le Mans Université, F-53020 Laval, France
- Correspondence:
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Südfeld C, Kiyani A, Wefelmeier K, Wijffels RH, Barbosa MJ, D’Adamo S. Expression of glycerol-3-phosphate acyltransferase increases non-polar lipid accumulation in Nannochloropsis oceanica. Microb Cell Fact 2023; 22:12. [PMID: 36647076 PMCID: PMC9844033 DOI: 10.1186/s12934-022-01987-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 12/09/2022] [Indexed: 01/18/2023] Open
Abstract
Microalgae are considered a suitable production platform for high-value lipids and oleochemicals. Several species including Nannochloropsis oceanica produce large amounts of essential [Formula: see text]-3 polyunsaturated fatty acids (PUFAs) which are integral components of food and feed and have been associated with health-promoting effects. N. oceanica can further accumulate high contents of non-polar lipids with chemical properties that render them a potential replacement for plant oils such as palm oil. However, biomass and lipid productivities obtained with microalgae need to be improved to reach commercial feasibility. Genetic engineering can improve biomass and lipid productivities, for instance by increasing carbon flux to lipids. Here, we report the overexpression of glycerol-3-phosphate acyltransferase (GPAT) in N. oceanica during favorable growth conditions as a strategy to increase non-polar lipid content. Transformants overproducing either an endogenous (NoGPAT) or a heterologous (Acutodesmus obliquus GPAT) GPAT enzyme targeted to the endoplasmic reticulum had up to 42% and 51% increased non-polar lipid contents, respectively, compared to the wild type. Biomass productivities of transformant strains were not substantially impaired, resulting in lipid productivities that were increased by up to 37% and 42% for NoGPAT and AoGPAT transformants, respectively. When exposed to nutrient stress, transformants and wild type had similar lipid contents, suggesting that GPAT enzyme exerts strong flux control on lipid synthesis in N. oceanica under favorable growth conditions. NoGPAT transformants further accumulated PUFAs in non-polar lipids, reaching a total of 6.8% PUFAs per biomass, an increase of 24% relative to the wild type. Overall, our results indicate that GPAT is an interesting target for engineering of lipid metabolism in microalgae, in order to improve non-polar lipid and PUFAs accumulation in microalgae.
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Affiliation(s)
- Christian Südfeld
- grid.4818.50000 0001 0791 5666Wageningen University, Bioprocess Engineering, PO Box 16, 6700 AA Wageningen, Netherlands
| | - Aamna Kiyani
- grid.4818.50000 0001 0791 5666Wageningen University, Bioprocess Engineering, PO Box 16, 6700 AA Wageningen, Netherlands ,grid.412621.20000 0001 2215 1297Department of Microbiology, Quaid-I-Azam University, Islamabad, 45320 Pakistan
| | - Katrin Wefelmeier
- grid.4818.50000 0001 0791 5666Wageningen University, Bioprocess Engineering, PO Box 16, 6700 AA Wageningen, Netherlands
| | - René H. Wijffels
- grid.4818.50000 0001 0791 5666Wageningen University, Bioprocess Engineering, PO Box 16, 6700 AA Wageningen, Netherlands ,grid.465487.cFaculty of Biosciences and Aquaculture, Nord University, N-8049 Bodø, Norway
| | - Maria J. Barbosa
- grid.4818.50000 0001 0791 5666Wageningen University, Bioprocess Engineering, PO Box 16, 6700 AA Wageningen, Netherlands
| | - Sarah D’Adamo
- grid.4818.50000 0001 0791 5666Wageningen University, Bioprocess Engineering, PO Box 16, 6700 AA Wageningen, Netherlands
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10
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Wang Z, Chu Y, Chang H, Xie P, Zhang C, Li F, Ho SH. Advanced insights on removal of antibiotics by microalgae-bacteria consortia: A state-of-the-art review and emerging prospects. CHEMOSPHERE 2022; 307:136117. [PMID: 35998727 DOI: 10.1016/j.chemosphere.2022.136117] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 08/02/2022] [Accepted: 08/16/2022] [Indexed: 06/15/2023]
Abstract
Antibiotics abuse has triggered a growing environmental problem, posing a major threat to both ecosystem and human health. Unfortunately, there are still several shortcomings to current antibiotics removal technologies. Microalgae-bacteria consortia have been shown to be a promising antibiotics treatment technology owing to advantages of high antibiotics removal efficiency, low operational cost, and carbon emission reduction. This review aims to introduce the removal mechanisms, influencing factors, and future research perspectives for using microalgae-bacteria consortia to remove antibiotics. The interaction mechanisms between microalgae and bacteria are comprehensively revealed, and their exclusive advantages have been summarized in a "Trilogy" strategy, including "reinforced physical contact", "upgraded substance utilization along with antibiotics degradation", and "robust biological regulation". What's more, the relationship between different interaction mechanisms is emphatically analyzed. The important influencing factors, including concentration and classes of antibiotics, environmental conditions, and operational parameters, of antibiotics removal were also assessed. Three innovative treatment systems (microalgae-bacteria fuel cells (MBFCs), microalgae-bacteria membrane photobioreactors (MB-MPBRs), and microalgae-bacteria granular sludge (MBGS)) along with three advanced techniques (metabolic engineering, machine learning, and molecular docking and dynamics) are then introduced. In addition, concrete implementing schemes of the above advanced techniques are also provided. Finally, the current challenges and future research directions in using microalgae-bacteria consortia to remove antibiotics have been summarized. Overall, this review addresses the current state of microalgae-bacteria consortia for antibiotics treatment and provides corresponding recommendations for enhancing antibiotics removal efficiency.
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Affiliation(s)
- Zeyuan Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China
| | - Yuhao Chu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China
| | - Haixing Chang
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing, 400054, PR China
| | - Peng Xie
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China
| | - Chaofan Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China.
| | - Fanghua Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China
| | - Shih-Hsin Ho
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China.
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11
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Zhu Z, Sun J, Fa Y, Liu X, Lindblad P. Enhancing microalgal lipid accumulation for biofuel production. Front Microbiol 2022; 13:1024441. [PMID: 36299727 PMCID: PMC9588965 DOI: 10.3389/fmicb.2022.1024441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Accepted: 09/26/2022] [Indexed: 11/13/2022] Open
Abstract
Microalgae have high lipid accumulation capacity, high growth rate and high photosynthetic efficiency which are considered as one of the most promising alternative sustainable feedstocks for producing lipid-based biofuels. However, commercialization feasibility of microalgal biofuel production is still conditioned to the high production cost. Enhancement of lipid accumulation in microalgae play a significant role in boosting the economics of biofuel production based on microalgal lipid. The major challenge of enhancing microalgal lipid accumulation lies in overcoming the trade-off between microalgal cell growth and lipid accumulation. Substantial approaches including genetic modifications of microalgal strains by metabolic engineering and process regulations of microalgae cultivation by integrating multiple optimization strategies widely applied in industrial microbiology have been investigated. In the present review, we critically discuss recent trends in the application of multiple molecular strategies to construct high performance microalgal strains by metabolic engineering and synergistic strategies of process optimization and stress operation to enhance microalgal lipid accumulation for biofuel production. Additionally, this review aims to emphasize the opportunities and challenges regarding scaled application of the strategic integration and its viability to make microalgal biofuel production a commercial reality in the near future.
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Affiliation(s)
- Zhi Zhu
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province, School of Life Sciences, Jiangsu Normal University, Xuzhou, China
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
- CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | - Jing Sun
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province, School of Life Sciences, Jiangsu Normal University, Xuzhou, China
| | - Yun Fa
- CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
| | - Xufeng Liu
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
- *Correspondence: Xufeng Liu,
| | - Peter Lindblad
- Microbial Chemistry, Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala, Sweden
- Peter Lindblad,
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12
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Jia B, Yin J, Li X, Li Y, Yang X, Lan C, Huang Y. Increased Lipids in Chlamydomonas reinhardtii by Multiple Regulations of DOF, LACS2, and CIS1. Int J Mol Sci 2022; 23:ijms231710176. [PMID: 36077572 PMCID: PMC9456367 DOI: 10.3390/ijms231710176] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 11/19/2022] Open
Abstract
Microalgal lipids are essential for biofuel and dietary supplement production. Lipid engineering for higher production has been studied for years. However, due to the complexity of lipid metabolism, single-gene engineering gradually encounters bottlenecks. Multiple gene regulation is more beneficial to boosting lipid accumulation and further clarifying the complex regulatory mechanism of lipid biosynthesis in the homeostasis of lipids, carbohydrates, and protein metabolism. Here, three lipid-related genes, DOF, LACS2, and CIS, were co-regulated in Chlamydomonas reinhartii by two circles of transformation to overexpress DOF and knock down LACS2 and CIS simultaneously. With the multiple regulations of these genes, the intracellular lipids and FA content increased by 142% and 52%, respectively, compared with CC849, whereas the starch and protein contents decreased by 45% and 24%. Transcriptomic analysis showed that genes in TAG and FA biosynthesis were up-regulated, and genes in starch and protein metabolism were down-regulated. This revealed that more carbon precursor fluxes from starch and protein metabolism were redirected towards lipid synthesis pathways. These results showed that regulating genes in various metabolisms contributed to carbon flux redirection and significantly improved intracellular lipids, demonstrating the potential of multiple gene regulation strategies and providing possible candidates for lipid overproduction in microalgae.
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13
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Zhang K, He J, Yin Y, Chen K, Deng X, Yu P, Li H, Zhao W, Yan S, Li M. Lysophosphatidic acid acyltransferase 2 and 5 commonly, but differently, promote seed oil accumulation in Brassica napus. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:83. [PMID: 35962411 PMCID: PMC9375321 DOI: 10.1186/s13068-022-02182-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 08/05/2022] [Indexed: 11/19/2022]
Abstract
Background Increasing seed oil content (SOC) of Brassica napus has become one of the main plant breeding goals over the past decades. Lysophosphatidic acid acyltransferase (LPAT) performs an important molecular function by regulating the production of phosphatidic acid (PA), a key intermediate in the synthesis of membrane and storage lipids. However, the mechanism underlying the effect of LPAT on the SOC of B. napus remains unclear. Results In the present study, significant elevation of SOC was achieved by overexpressing BnLPAT2 and BnLPAT5 in B. napus. RNAi and CRISPR–Cas9 were also successfully used to knock down and knock out these two genes in B. napus where SOC significantly decreased. Meanwhile, we found an accumulation of lipid droplets and oil bodies in seeds of BnLPAT2 and BnLPAT5 overexpression lines, whereas an increase of sugar and protein in Bnlpat2 and Bnlpat5 mutant seeds. Sequential transcriptome analysis was further performed on the developing seeds of the BnLPAT2 and BnLPAT5 overexpression, knockdown, and knockout rapeseed lines. Most differentially expressed genes (DEGs) that were expressed in the middle and late stages of seed development were enriched in photosynthesis and lipid metabolism, respectively. The DEGs involved in fatty acid and lipid biosynthesis were active in the overexpression lines but were relatively inactive in the knockdown and knockout lines. Further analysis revealed that the biological pathways related to fatty acid/lipid anabolism and carbohydrate metabolism were specifically enriched in the BnLPAT2 overexpression lines. Conclusions BnLPAT2 and BnLPAT5 are essential for seed oil accumulation. BnLPAT2 preferentially promoted diacylglycerol synthesis to increase SOC, whereas BnLPAT5 tended to boost PA synthesis for membrane lipid generation. Taken together, BnLPAT2 and BnLPAT5 can jointly but differently promote seed oil accumulation in B. napus. This study provides new insights into the potential mechanisms governing the promotion of SOC by BnLPAT2 and BnLPAT5 in the seeds of B. napus. Supplementary Information The online version contains supplementary material available at 10.1186/s13068-022-02182-2.
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Xin F, Wang R, Chang Y, Gao M, Xie Z, Yang W, Chen M, Zhang H, Song Y. Homologous Overexpression of Diacylglycerol Acyltransferase in Oleaginous Fungus Mucor circinelloides WJ11 Enhances Lipid Accumulation under Static Solid Cultivation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:9073-9083. [PMID: 35844180 DOI: 10.1021/acs.jafc.2c03489] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Diacylglycerol acyltransferase (DGAT) catalyzes the binding of acyl-CoA to diacylglycerol to form triacylglycerol (TAG). Previous studies strongly indicate that DGAT2, rather than DGAT1, is crucial for TAG accumulation in the oleaginous fungus Mucor circinelloides. To increase the lipid content of M. circinelloides WJ11, McDGAT2 was overexpressed by homologous recombination; compared to the control strain Mc2075, transformants McDGAT2d showed a significant increase in biomass for both spores and mycelia (from 87.7 to 101.2 mg/g in spores and from 75.6 to 93.1 mg/g in mycelia). McDGAT2 overexpression under static solid fermentation gave a greater boost to lipid accumulation in mycelia than in spores. Total fatty acid content in mycelia increased by 68.0% (from 13.6 to 22.8%) and in spores by 26.3% (from 10.6 to 13.4%). However, under submerged fermentation, the lipid content of McDGAT2d was the same as the control, while biomass was slightly reduced. Transcriptomics showed that NADPH was derived mainly from the pentose phosphate pathway, acetyl-CoA was from multiple pathways, and leucine metabolism played an important role in substrate supply for fatty acid biosynthesis. Static solid fermentation may be the more suitable fermentation method for microbial oil production by filamentous fungi due to its lower fermentation costs.
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Affiliation(s)
- Feifei Xin
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, Shandong 255000, People's Republic of China
| | - Ruixue Wang
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, Shandong 255000, People's Republic of China
| | - Yufei Chang
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, Shandong 255000, People's Republic of China
| | - Meng Gao
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, Shandong 255000, People's Republic of China
| | - Zhike Xie
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, Shandong 255000, People's Republic of China
| | - Wu Yang
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, Shandong 255000, People's Republic of China
| | - Meiling Chen
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, Shandong 255000, People's Republic of China
| | - Huaiyuan Zhang
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, Shandong 255000, People's Republic of China
| | - Yuanda Song
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, Shandong 255000, People's Republic of China
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15
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Yang YF, Li DW, Balamurugan S, Wang X, Yang WD, Li HY. Chrysolaminarin biosynthesis in the diatom is enhanced by overexpression of 1,6-β-transglycosylase. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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16
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Karpagam R, Jawaharraj K, Ashokkumar B, Pugalendhi A, Varalakshmi P. A cheap two-step cultivation of Phaeodactylum tricornutum for increased TAG production and differential expression of TAG biosynthesis associated genes. J Biotechnol 2022; 354:53-62. [PMID: 35709890 DOI: 10.1016/j.jbiotec.2022.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 05/06/2022] [Accepted: 06/06/2022] [Indexed: 12/28/2022]
Abstract
A cheap cultivation of microalgae greatly reduces the biodiesel production cost. Subsequently in this study, citric acid and effluents from sugar and tannery industries were used as the nutritional supplements for the improvement of biomass and TAG production in Phaeodactylum tricornutum using two-step cultivation. When compared to control (media without supplementation), a considerable increase in biomass and chlorophyll a was obtained with citric acid (CA) and sugar industry effluent (SIE) supplemented media. In the two-step cultivation method, biomass raised from CA (100mg·L-1) and SIE (1.5mL·L-1) supplementations in the first step, viz. biomass production (BP) step was allowed for lipid accumulation in the second step, viz. lipid production (LP) step, and thus yielded enhanced lipids of 11.5 ± 0.7mg·L-1·day-1 and 13.5 ± 1.9mg·L-1·day-1 respectively, with improved TAG synthesis. Further, differential expression analysis of TAG biosynthetic genes of P. tricornutum under single-step and two-step cultivation modes were performed, and the gene expression patterns were studied.
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Affiliation(s)
- Rathinasamy Karpagam
- Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai 625021, Tamil Nadu, India
| | - Kalimuthu Jawaharraj
- Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai 625021, Tamil Nadu, India
| | - Balasubramaniem Ashokkumar
- Department of Genetic Engineering, School of Biotechnology, Madurai Kamaraj University, Madurai 625021, Tamil Nadu, India
| | - Arivazhagan Pugalendhi
- Innovative Green Product Syntheis and Renewable Environment Development Research Group, Faculty of Environment and Labour Safety, TonDuc Thang University, Ho Chi Minh City, Vietnam
| | - Perumal Varalakshmi
- Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai 625021, Tamil Nadu, India.
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Wang X, Mou JH, Qin ZH, Hao TB, Zheng L, Buhagiar J, Liu YH, Balamurugan S, He Y, Lin CSK, Yang WD, Li HY. Supplementation with rac-GR24 Facilitates the Accumulation of Biomass and Astaxanthin in Two Successive Stages of Haematococcus pluvialis Cultivation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:4677-4689. [PMID: 35384649 DOI: 10.1021/acs.jafc.2c00479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The unicellular freshwater green alga Haematococcus pluvialis has attracted much research attention due to its biosynthetic ability for large amounts of astaxanthin, a blood-red ketocarotenoid that is used in cosmetics, nutraceuticals, and pharmaceuticals. Recently, numerous studies have investigated the functions of natural astaxanthin; however, the high cost of the production of astaxanthin from H. pluvialis cultures restricts its commercial viability. There is an urgent need to fulfill commercial demands by increasing astaxanthin accumulation from H. pluvialis cultures. In this study, we discovered that treatment of H. pluvialis cultures at the beginning of the macrozooid stage (day 0) with 1 μM rac-GR24, a synthetic analogue of strigolactones (a class of phytohormones), led to significant increases in biomass [up to a maximum dry cell weight (DCW) of 0.53 g/L] during the macrozooid stage and astaxanthin (from 0.63 to 5.32% of DCW) during the hematocyst stage. We elucidated that this enhancement of biomass accumulation during the macrozooid stage by rac-GR24 is due to its increasing CO2 utilization efficiency in photosynthesis and carbohydrate biosynthesis. We also found that rac-GR24 stimulated the overproduction of nicotinamide adenine dinucleotide phosphate (NADPH) and antioxidant enzymes in H. pluvialis cultures, which alleviated the oxidative damage caused by reactive oxygen species generated during the hematocyst stage due to the exhaustion of nitrogen supplies. Moreover, rac-GR24 treatment of H. pluvialis synergistically altered the activity of the pathways of fatty acid biosynthesis and astaxanthin esterification, which resulted in larger amounts of astaxanthin being generated by rac-GR24-treated cultures than by controls. In summary, we have developed a feasible and economic rac-GR24-assisted strategy that increases the amounts of biomass and astaxanthin generated by H. pluvialis cultures, and have provided novel insights into the mechanistic roles of rac-GR24 to achieve these effects.
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Affiliation(s)
- Xiang Wang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510000, China
| | - Jin-Hua Mou
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon 999077, Hong Kong, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510000, China
| | - Zi-Hao Qin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon 999077, Hong Kong, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510000, China
| | - Ting-Bin Hao
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Lan Zheng
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Joseph Buhagiar
- Department of Biology, University of Malta, Msida 2080, Malta
| | - Yu-Hong Liu
- Key Laboratory of Animal Molecular Design and Precise Breeding of Guangdong Higher Education Institutes, School of Life Science and Engineering, Foshan University, Foshan 528231, China
| | | | - Yuhe He
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon 999077, Hong Kong, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510000, China
| | - Carol Sze Ki Lin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon 999077, Hong Kong, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510000, China
| | - Wei-Dong Yang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Hong-Ye Li
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
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18
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Latest Expansions in Lipid Enhancement of Microalgae for Biodiesel Production: An Update. ENERGIES 2022. [DOI: 10.3390/en15041550] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Research progress on sustainable and renewable biofuel has gained motion over the years, not just due to the rapid reduction of dwindling fossil fuel supplies but also due to environmental and potential energy security issues as well. Intense interest in microalgae (photosynthetic microbes) as a promising feedstock for third-generation biofuels has grown over recent years. Fuels derived from algae are now considered sustainable biofuels that are promising, renewable, and clean. Therefore, selecting the robust species of microalgae with substantial features for quality biodiesel production is the first step in the way of biofuel production. A contemporary investigation is more focused on several strategies and techniques to achieve higher biomass and triglycerides in microalgae. The improvement in lipid enhancement in microalgae species by genetic manipulation approaches, such as metabolic or genetic alteration, and the use of nanotechnology are the most recent ways of improving the production of biomass and lipids. Hence, the current review collects up-to-date approaches for microalgae lipid increase and biodiesel generation. The strategies for high biomass and high lipid yield are discussed. Additionally, various pretreatment procedures that may aid in lipid harvesting efficiency and improve lipid recovery rate are described.
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Kang NK, Baek K, Koh HG, Atkinson CA, Ort DR, Jin YS. Microalgal metabolic engineering strategies for the production of fuels and chemicals. BIORESOURCE TECHNOLOGY 2022; 345:126529. [PMID: 34896527 DOI: 10.1016/j.biortech.2021.126529] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 06/14/2023]
Abstract
Microalgae are promising sustainable resources because of their ability to convert CO2 into biofuels and chemicals directly. However, the industrial production and economic feasibility of microalgal bioproducts are still limited. As such, metabolic engineering approaches have been undertaken to enhance the productivities of microalgal bioproducts. In the last decade, impressive advances in microalgae metabolic engineering have been made by developing genetic engineering tools and multi-omics analysis. This review presents comprehensive microalgal metabolic pathways and metabolic engineering strategies for producing lipids, long chain-polyunsaturated fatty acids, terpenoids, and carotenoids. Additionally, promising metabolic engineering approaches specific to target products are summarized. Finally, this review discusses current challenges and provides future perspectives for the effective production of chemicals and fuels via microalgal metabolic engineering.
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Affiliation(s)
- Nam Kyu Kang
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Kwangryul Baek
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Hyun Gi Koh
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Christine Anne Atkinson
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Donald R Ort
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Global Change and Photosynthesis Research Unit, Agricultural Research Service, United States Department of Agriculture, Urbana, IL, USA; Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Yong-Su Jin
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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20
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Muthukrishnan L. Bio‐engineering of microalgae: Challenges and future prospects toward industrial and environmental applications. J Basic Microbiol 2022; 62:310-329. [DOI: 10.1002/jobm.202100417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 12/28/2021] [Accepted: 01/08/2022] [Indexed: 01/29/2023]
Affiliation(s)
- Lakshmipathy Muthukrishnan
- Department of Conservative Dentistry and Endodontics, Saveetha Dental College and Hospitals Saveetha Institute of Medical and Technical Sciences Chennai Tamil Nadu India
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21
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Scarsini M, Thiriet-Rupert S, Veidl B, Mondeguer F, Hu H, Marchand J, Schoefs B. The Transition Toward Nitrogen Deprivation in Diatoms Requires Chloroplast Stand-By and Deep Metabolic Reshuffling. FRONTIERS IN PLANT SCIENCE 2022; 12:760516. [PMID: 35126407 PMCID: PMC8811913 DOI: 10.3389/fpls.2021.760516] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 11/19/2021] [Indexed: 06/14/2023]
Abstract
Microalgae have adapted to face abiotic stresses by accumulating energy storage molecules such as lipids, which are also of interest to industries. Unfortunately, the impairment in cell division during the accumulation of these molecules constitutes a major bottleneck for the development of efficient microalgae-based biotechnology processes. To address the bottleneck, a multidisciplinary approach was used to study the mechanisms involved in the transition from nitrogen repletion to nitrogen starvation conditions in the marine diatom Phaeodactylum tricornutum that was cultured in a turbidostat. Combining data demonstrate that the different steps of nitrogen deficiency clustered together in a single state in which cells are in equilibrium with their environment. The switch between the nitrogen-replete and the nitrogen-deficient equilibrium is driven by intracellular nitrogen availability. The switch induces a major gene expression change, which is reflected in the reorientation of the carbon metabolism toward an energy storage mode while still operating as a metabolic flywheel. Although the photosynthetic activity is reduced, the chloroplast is kept in a stand-by mode allowing a fast resuming upon nitrogen repletion. Altogether, these results contribute to the understanding of the intricate response of diatoms under stress.
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Affiliation(s)
- Matteo Scarsini
- Metabolism, Bio-Engineering of Microalgal Molecules and Applications (MIMMA), Mer Molécules Santé, IUML—FR 3473 CNRS, Le Mans University, Le Mans, France
| | - Stanislas Thiriet-Rupert
- Metabolism, Bio-Engineering of Microalgal Molecules and Applications (MIMMA), Mer Molécules Santé, IUML—FR 3473 CNRS, Le Mans University, Le Mans, France
- Institut Pasteur, Genetics of Biofilms Laboratory, Paris, France
| | - Brigitte Veidl
- Metabolism, Bio-Engineering of Microalgal Molecules and Applications (MIMMA), Mer Molécules Santé, IUML—FR 3473 CNRS, Le Mans University, Le Mans, France
| | - Florence Mondeguer
- Phycotoxins Laboratory, Institut Français de Recherche pour l'Exploitation de la Mer, Nantes, France
| | - Hanhua Hu
- Key Laboratory of Algal Biology, Chinese Academy of Sciences, Wuhan, China
| | - Justine Marchand
- Metabolism, Bio-Engineering of Microalgal Molecules and Applications (MIMMA), Mer Molécules Santé, IUML—FR 3473 CNRS, Le Mans University, Le Mans, France
| | - Benoît Schoefs
- Metabolism, Bio-Engineering of Microalgal Molecules and Applications (MIMMA), Mer Molécules Santé, IUML—FR 3473 CNRS, Le Mans University, Le Mans, France
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22
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Genetic engineering of microalgae for enhanced lipid production. Biotechnol Adv 2021; 52:107836. [PMID: 34534633 DOI: 10.1016/j.biotechadv.2021.107836] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 09/09/2021] [Accepted: 09/09/2021] [Indexed: 12/24/2022]
Abstract
Microalgae have the potential to become microbial cell factories for lipid production. Their ability to convert sunlight and CO2 into valuable lipid compounds has attracted interest from cosmetic, biofuel, food and feed industries. In order to make microalgae-derived products cost-effective and commercially competitive, enhanced growth rates and lipid productivities are needed, which require optimization of cultivation systems and strain improvement. Advances in genetic tool development and omics technologies have increased our understanding of lipid metabolism, which has opened up possibilities for targeted metabolic engineering. In this review we provide a comprehensive overview on the developments made to genetically engineer microalgal strains over the last 30 years. We focus on the strategies that lead to an increased lipid content and altered fatty acid profile. These include the genetic engineering of the fatty acid synthesis pathway, Kennedy pathway, polyunsaturated fatty acid and triacylglycerol metabolisms and fatty acid catabolism. Moreover, genetic engineering of specific transcription factors, NADPH generation and central carbon metabolism, which lead to increase of lipid accumulation are also reviewed.
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23
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Hao TB, Lu Y, Zhang ZH, Liu SF, Wang X, Yang WD, Balamurugan S, Li HY. Hyperaccumulation of fucoxanthin by enhancing methylerythritol phosphate pathway in Phaeodactylum tricornutum. Appl Microbiol Biotechnol 2021; 105:8783-8793. [PMID: 34741642 DOI: 10.1007/s00253-021-11660-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 08/09/2021] [Accepted: 10/22/2021] [Indexed: 11/30/2022]
Abstract
The established human health benefits of carotenoids along with the contemporary consumption of natural carotenoids bring the necessity to sustainable production of carotenoids. Among, marine diatoms have emerged as the potential biological resources for carotenoid production; however, their relatively lower yield in native strains provides the impetus to genetically improve the diatoms to cope with the burgeoning demand. In this study, we genetically improved the diatom Phaeodactylum tricornutum by overexpressing key carotenogenic genes involved in methylerythritol phosphate (MEP) pathway. The genes with lower relative transcript level under optimum conditions such as CMK and CMS were selected and overexpressed in P. tricornutum individually. Both CMK and CMS overexpressing lines exhibited elevated growth and photosynthesis. The expression of key carotenogenic genes such as PSY, PDS, ZDS, CRT, and LCYB was significantly upregulated. Furthermore, total carotenoid content was significantly increased; particularly, fucoxanthin content was increased by 1.83- and 1.82-fold in engineered lines CMK and CMS, respectively. Together, the results identify the potential metabolic targets and also uncover the crucial role of MEP pathway in redirecting metabolic precursors towards carotenogenesis. KEY POINTS: • Low abundant genes CMS and CMK of MEP pathway were overexpressed in the diatom • Total carotenoid content was increased, particularly fucoxanthin • Critical metabolic nodes were uncovered to accelerate fucoxanthin biosynthesis.
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Affiliation(s)
- Ting-Bin Hao
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632, China
| | - Yang Lu
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632, China
| | - Zhong-Hong Zhang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632, China
| | - Si-Fen Liu
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632, China
| | - Xiang Wang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632, China
| | - Wei-Dong Yang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632, China
| | | | - Hong-Ye Li
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632, China.
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24
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Castiglia D, Landi S, Esposito S. Advanced Applications for Protein and Compounds from Microalgae. PLANTS (BASEL, SWITZERLAND) 2021; 10:1686. [PMID: 34451730 PMCID: PMC8398235 DOI: 10.3390/plants10081686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/10/2021] [Accepted: 08/13/2021] [Indexed: 05/02/2023]
Abstract
Algal species still show unrevealed and unexplored potentiality for the identification of new compounds. Photosynthetic organisms represent a valuable resource to exploit and sustain the urgent need of sustainable and green technologies. Particularly, unconventional organisms from extreme environments could hide properties to be employed in a wide range of biotechnology applications, due to their peculiar alleles, proteins, and molecules. In this review we report a detailed dissection about the latest and advanced applications of protein derived from algae. Furthermore, the innovative use of modified algae as bio-reactors to generate proteins or bioactive compounds was discussed. The latest progress about pharmaceutical applications, including the possibility to obtain drugs to counteract virus (as SARS-CoV-2) were also examined. The last paragraph will survey recent cases of the utilization of extremophiles as bio-factories for specific protein and molecule production.
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Affiliation(s)
- Daniela Castiglia
- Bio-Organic Chemistry Unit, Institute of Biomolecular Chemistry CNR, Via Campi Flegrei 34, 80078 Pozzuoli, Italy;
| | - Simone Landi
- Department of Biology, University of Naples “Federico II”, Via Cinthia, 80126 Napoli, Italy;
| | - Sergio Esposito
- Department of Biology, University of Naples “Federico II”, Via Cinthia, 80126 Napoli, Italy;
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25
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Xue J, Li T, Chen TT, Balamurugan S, Yang WD, Li HY. Regulation of malate-pyruvate pathway unifies the adequate provision of metabolic carbon precursors and NADPH in Tetradesmus obliquus. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102340] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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26
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Sittmann J, Bae M, Mevers E, Li M, Quinn A, Sriram G, Clardy J, Liu Z. Bacterial diketopiperazines stimulate diatom growth and lipid accumulation. PLANT PHYSIOLOGY 2021; 186:1159-1170. [PMID: 33620482 PMCID: PMC8195512 DOI: 10.1093/plphys/kiab080] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 02/03/2021] [Indexed: 06/10/2023]
Abstract
Diatoms are photosynthetic microalgae that fix a significant fraction of the world's carbon. Because of their photosynthetic efficiency and high-lipid content, diatoms are priority candidates for biofuel production. Here, we report that sporulating Bacillus thuringiensis and other members of the Bacillus cereus group, when in co-culture with the marine diatom Phaeodactylum tricornutum, significantly increase diatom cell count. Bioassay-guided purification of the mother cell lysate of B. thuringiensis led to the identification of two diketopiperazines (DKPs) that stimulate both P. tricornutum growth and increase its lipid content. These findings may be exploited to enhance P. tricornutum growth and microalgae-based biofuel production. As increasing numbers of DKPs are isolated from marine microbes, the work gives potential clues to bacterial-produced growth factors for marine microalgae.
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Affiliation(s)
- John Sittmann
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - Munhyung Bae
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Emily Mevers
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Muzi Li
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - Andrew Quinn
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20742, USA
| | - Ganesh Sriram
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20742, USA
| | - Jon Clardy
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Zhongchi Liu
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
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27
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Zhang Y, Ye Y, Bai F, Liu J. The oleaginous astaxanthin-producing alga Chromochloris zofingiensis: potential from production to an emerging model for studying lipid metabolism and carotenogenesis. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:119. [PMID: 33992124 PMCID: PMC8126118 DOI: 10.1186/s13068-021-01969-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 05/07/2021] [Indexed: 05/05/2023]
Abstract
The algal lipids-based biodiesel, albeit having advantages over plant oils, still remains high in the production cost. Co-production of value-added products with lipids has the potential to add benefits and is thus believed to be a promising strategy to improve the production economics of algal biodiesel. Chromochloris zofingiensis, a unicellular green alga, has been considered as a promising feedstock for biodiesel production because of its robust growth and ability of accumulating high levels of triacylglycerol under multiple trophic conditions. This alga is also able to synthesize high-value keto-carotenoids and has been cited as a candidate producer of astaxanthin, the strongest antioxidant found in nature. The concurrent accumulation of triacylglycerol and astaxanthin enables C. zofingiensis an ideal cell factory for integrated production of the two compounds and has potential to improve algae-based production economics. Furthermore, with the advent of chromosome-level whole genome sequence and genetic tools, C. zofingiensis becomes an emerging model for studying lipid metabolism and carotenogenesis. In this review, we summarize recent progress on the production of triacylglycerol and astaxanthin by C. zofingiensis. We also update our understanding in the distinctive molecular mechanisms underlying lipid metabolism and carotenogenesis, with an emphasis on triacylglycerol and astaxanthin biosynthesis and crosstalk between the two pathways. Furthermore, strategies for trait improvements are discussed regarding triacylglycerol and astaxanthin synthesis in C. zofingiensis.
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Affiliation(s)
- Yu Zhang
- Laboratory for Algae Biotechnology and Innovation, College of Engineering, Peking University, Beijing, 100871, China
| | - Ying Ye
- Laboratory for Algae Biotechnology and Innovation, College of Engineering, Peking University, Beijing, 100871, China
| | - Fan Bai
- Laboratory for Algae Biotechnology and Innovation, College of Engineering, Peking University, Beijing, 100871, China
| | - Jin Liu
- Laboratory for Algae Biotechnology and Innovation, College of Engineering, Peking University, Beijing, 100871, China.
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28
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Ashtiani FR, Jalili H, Rahaie M, Sedighi M, Amrane A. Effect of mixed culture of yeast and microalgae on acetyl-CoA carboxylase and Glycerol-3-phosphate acyltransferase expression. J Biosci Bioeng 2020; 131:364-372. [PMID: 33341347 DOI: 10.1016/j.jbiosc.2020.11.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 11/09/2020] [Accepted: 11/23/2020] [Indexed: 10/22/2022]
Abstract
In recent years, some studies have reported that co-culturing green algae and yeast improve lipid and biomass concentration. In this study, a co-culture of the oleaginous yeast Rhodotorula glutinis and the microalgae Chlorella vulgaris was consequently conducted with inoculation of microalga and yeast in growth and stationary phases, respectively. For the first time, the expression of two pivotal enzymes in fatty acids synthetic pathway, acetyl-CoA carboxylase and Glycerol-3-phosphate acyltransferase, was evaluated. To evaluate the synergistic impacts of the mixed culture on the enzymes expression, several co-culture models were designed, including the use of different ratio of microalgae to yeast or the use of residual cell-free medium of yeast; a positive impact on enzymes overexpression was shown in the case of the co-culture of the two microorganisms, and when the remaining cell-free medium of yeast was added to the microalgal culture. The results of in vitro co-culture demonstrated increased 6- and 5-fold of nervonic acid (C24:1) and behenic acid (C22:0) concentrations, respectively, in 2:1 microalgae to yeast co-culture as compared to the monoculture batches. Addition of yeast residual cell-free medium in the 2:1 ratio to the microalgal culture enhanced 9 and 6 times nervonic acid (C24:1) and behenic acid (C22:0) amounts, respectively.
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Affiliation(s)
- Fatemeh-Rezaee Ashtiani
- Department of Life Sciences Engineering, Faculty of New Sciences and Technologies, University of Tehran, Tehran 14395-1561, Iran
| | - Hasan Jalili
- Department of Life Sciences Engineering, Faculty of New Sciences and Technologies, University of Tehran, Tehran 14395-1561, Iran.
| | - Mahdi Rahaie
- Department of Life Sciences Engineering, Faculty of New Sciences and Technologies, University of Tehran, Tehran 14395-1561, Iran
| | - Mahsa Sedighi
- Cellular and Molecular Research Center, Birjand University of Medical Sciences, Birjand, Iran; Department of Nanomedicine, Faculty of Medicine, Birjand University of Medical Sciences, Birjand, Iran
| | - Abdeltif Amrane
- Université de Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR-UMR 6226, F-35000 Rennes, France
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29
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Liu B, Sun Y, Hang W, Wang X, Xue J, Ma R, Jia X, Li R. Characterization of a Novel Acyl-ACP Δ 9 Desaturase Gene Responsible for Palmitoleic Acid Accumulation in a Diatom Phaeodactylum tricornutum. Front Microbiol 2020; 11:584589. [PMID: 33391203 PMCID: PMC7772203 DOI: 10.3389/fmicb.2020.584589] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 11/17/2020] [Indexed: 12/23/2022] Open
Abstract
Palmitoleic acid (16:1Δ9) possesses a double bond at the seventh carbon atom from methyl end of the acyl chain and belongs to unusual ω-7 monounsaturated fatty acids with broad applications in food, pharmaceuticals, cosmetics, biofuel, and other industries. This high-value fatty acid accumulates up to >40% of total lipid in the marine diatom Phaeodactylum tricornutum. The present study was conducted to determine the key gene responsible for 16:1Δ9 biosynthesis in this unicellular alga. A new full-length cDNA and genomic DNA encoding acyl-ACP Δ9 desaturase (PtAAD) were isolated from P. tricornutum cells. Expression levels of PtAAD gene under normal and stress culture conditions were both positively correlated with 16:1Δ9 accumulation, implying its potential role for fatty acid determination. Functional complementation assay of a yeast mutant strain BY4839 evidenced that PtAAD could restore the synthesis of unsaturated fatty acid, especially generating high levels of 16:1Δ9. Further transient expression of PtAAD gene in Nicotiana benthamiana leaves was accompanied by the accumulation of 16:1Δ9, which was absent from control groups. Three-dimensional structure modeling studies showed that functional domain of PtAAD contained three variant amino acids (F160, A223, and L156), which may narrow the space shape of substrate-binding cavity to ensure the entry of 16:0-ACP. Consistent with this prediction, the mutated version of PtAAD gene (F160L, A223T, and L156M) in N. benthamiana systems failed to accumulate 16:1Δ9, but increased levels of 18:1Δ9. Taken together, PtAAD exhibits a strong enzymatic activity and substrate preference for 16:0-ACP, acting as the key player for high biosynthesis and accumulation of 16:1Δ9 in this alga. These findings provide new insights for better understanding the palmitoleic acid and oil biosynthetic mechanism in P. tricornutum, indicating that PtAAD gene may have practical applications for enriching palmitoleic acid and oil yield in other commercial oleaginous algae and crops.
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Affiliation(s)
- Baoling Liu
- College of Agriculture, Shanxi Agricultural University, Jinzhong, China.,College of Plant Protection, Shanxi Agricultural University, Jinzhong, China
| | - Yan Sun
- College of Agriculture, Shanxi Agricultural University, Jinzhong, China
| | - Wei Hang
- College of Agriculture, Shanxi Agricultural University, Jinzhong, China
| | - Xiaodan Wang
- College of Agriculture, Shanxi Agricultural University, Jinzhong, China
| | - Jinai Xue
- College of Agriculture, Shanxi Agricultural University, Jinzhong, China
| | - Ruiyan Ma
- College of Plant Protection, Shanxi Agricultural University, Jinzhong, China
| | - Xiaoyun Jia
- College of Agriculture, Shanxi Agricultural University, Jinzhong, China
| | - Runzhi Li
- College of Agriculture, Shanxi Agricultural University, Jinzhong, China
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30
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Wang X, Zhang MM, Sun Z, Liu SF, Qin ZH, Mou JH, Zhou ZG, Lin CSK. Sustainable lipid and lutein production from Chlorella mixotrophic fermentation by food waste hydrolysate. JOURNAL OF HAZARDOUS MATERIALS 2020; 400:123258. [PMID: 32947693 DOI: 10.1016/j.jhazmat.2020.123258] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 04/24/2020] [Accepted: 06/18/2020] [Indexed: 06/11/2023]
Abstract
Bioconversion of food waste into value-added products is a promising way to tackle the global food waste management problem. In this study, a novel valorisation strategy for bioenergy and lutein production via microalgal fermentation was investigated. Significant amount of glucose was recovered from enzymatic hydrolysis of food waste. The resultant hydrolysate was then utilised as culture medium in mixotrophic cultivation of Chlorella sp. to obtain high levels of lipid and lutein, whose accumulation patterns were consistent with molecular analyses. The resultant algal lipid derived from microalgal biomass using food hydrolysate was at high quality in terms of biodiesel properties. Further, in semi-continuous fermentation, the average algal biomass was 6.1 g L-1 with 2.5 g L-1 lipid and 38.5 mg L-1 lutein using hydrolysate with an initial glucose concentration of 10 g L-1. Meanwhile, the resultant algal biomass was 6.9 g L-1 with 1.8 g L-1 lipid and 63.0 mg L-1 lutein using hydrolysate with an initial glucose concentration of 20 g L-1, which suggests food waste hydrolysate could trigger algal products preferences. The experimental results of this study suggested the potential of microalgae as a platform for bioconversion of food waste into high-value products, especially sustainable bioenergy.
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Affiliation(s)
- Xiang Wang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education; International Research Center for Marine Biosciences, Ministry of Science and Technology; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, 201306, China; School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China; Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Man-Man Zhang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education; International Research Center for Marine Biosciences, Ministry of Science and Technology; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, 201306, China; School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Zheng Sun
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education; International Research Center for Marine Biosciences, Ministry of Science and Technology; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, 201306, China.
| | - Si-Fen Liu
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Zi-Hao Qin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Jin-Hua Mou
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Zhi-Gang Zhou
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education; International Research Center for Marine Biosciences, Ministry of Science and Technology; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, 201306, China
| | - Carol Sze Ki Lin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
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Chungjatupornchai W, Fa-Aroonsawat S. Enhanced triacylglycerol production in oleaginous microalga Neochloris oleoabundans by co-overexpression of lipogenic genes: Plastidial LPAAT1 and ER-located DGAT2. J Biosci Bioeng 2020; 131:124-130. [PMID: 33069576 DOI: 10.1016/j.jbiosc.2020.09.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 09/18/2020] [Accepted: 09/18/2020] [Indexed: 12/29/2022]
Abstract
Microalgae accumulate lipid triacylglycerol (TAG), a promising feedstock for production of natural edible oils and biofuels. To make products derived from microalgal TAG economically viable, increasing TAG content and productivity are of high importance. To increase TAG content, two endogenous key enzymes of TAG biosynthesis: plastidial lysophosphatidic acid acyltransferase (NeoLPAAT1) and endoplasmic reticulum-located diacylglycerol acyltransferase 2 (NeoDGAT2) were co-overexpressed in oleaginous microalga Neochloris oleoabundans. The neutral lipid content in NeoLPAAT1-NeoDGAT2 co-overexpressing transformant detected by Nile red staining increased 2-fold without compromising cell growth. The transcriptional levels of NeoLPAAT1 and NeoDGAT2 levels were 1.9-fold higher in the transformant than wild type. Considerably higher lipid accumulation was found in the transformant than wild type: total lipid content (73.72 ± 4.17 % DCW) increased 1.6-fold, TAG content (50.63 ± 6.15 % DCW) increased 2.1-fold, total lipid productivity (16.84 ± 0.66 mg/L/day) increased 1.9-fold, and TAG productivity (11.68 ± 0.90 mg/L/day) increased 2.1-fold. Fatty acid composition was slightly altered in the transformant compared to wild type; saturated fatty acid C16:0 increased to 26% from 20%, whereas C18:0 was reduced to 7% from 14%. Long-term stability of NeoLPAAT1-NeoDGAT2 co-overexpression was observed in the transformant continuously maintained on solid medium in a period of 4 years. The results suggested that targeted engineering of genes in pathway located at different organelles should be possible in microalgal lipid metabolism.
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Affiliation(s)
- Wipa Chungjatupornchai
- Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakhon Pathom 73170, Thailand.
| | - Sirirat Fa-Aroonsawat
- Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakhon Pathom 73170, Thailand.
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32
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Wang X, Liu SF, Qin ZH, Balamurugan S, Li HY, Lin CSK. Sustainable and stepwise waste-based utilisation strategy for the production of biomass and biofuels by engineered microalgae. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 265:114854. [PMID: 32504890 DOI: 10.1016/j.envpol.2020.114854] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 05/04/2020] [Accepted: 05/20/2020] [Indexed: 05/08/2023]
Abstract
Waste streams have emerged as potential feedstocks for biofuel production via microbial bioconversion. Metabolic engineering of the microalga Phaeodactylum tricornutum in its lipid biosynthetic pathways has been conducted with an aim to improve lipid production. However, there has been only limited achievement in satisfying biofuel demands by utilising extracellular organic carbons from low-cost waste streams. Herein, we present a successive staged cultivation mode, based on a previously engineered strain that co-overexpresses two key triacylglycerol biosynthesis genes. We first optimised microalgal biomass and lipid production by using food waste hydrolysate and crude glycerol as the cultivation media. Food waste hydrolysate (5% v/v) is a low-cost organic carbon source for enhanced microalgal biomass production, and the resulting lipid concentration was 1.08-fold higher with food-waste hydrolysate than that of the defined medium. Additionally, the resultant lipid concentration after using crude glycerol (100 mM) was 1.24-fold higher than that using the defined medium. Two carbon feeding modes (hybrid and sequential) were also performed to investigate the potential of engineered P. tricornutum with preliminary mechanistic analyses. The biodiesel properties of lipids produced in the hybrid mode were evaluated for potential application prospects. Collectively, this study demonstrates a waste stream utilisation strategy for efficient and sustainable microalgal biofuel production.
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Affiliation(s)
- Xiang Wang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China; School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Si-Fen Liu
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Zi-Hao Qin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Srinivasan Balamurugan
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China; Department of Biotechnology, Bharathidasan University, Tiruchirappalli, 620024, India
| | - Hong-Ye Li
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Carol Sze Ki Lin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
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Fayyaz M, Chew KW, Show PL, Ling TC, Ng IS, Chang JS. Genetic engineering of microalgae for enhanced biorefinery capabilities. Biotechnol Adv 2020; 43:107554. [PMID: 32437732 DOI: 10.1016/j.biotechadv.2020.107554] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 05/06/2020] [Accepted: 05/06/2020] [Indexed: 02/06/2023]
Abstract
Microalgae-based bioproducts are in limelight because of their promising future, novel characteristics, the current situation of population needs, and rising prices of rapidly depleting energy resources. Algae-based products are considered as clean sustainable energy and food resources. At present, they are not commercialized due to their high production cost and low yield. In recent years, novel genome editing tools like RNAi, ZNFs, TALENs, and CRISPR/Cas9 are used to enhance the quality and quantity of the desired products. Genetic and metabolic engineering are frequently applied because of their rapid and precise results than random mutagenesis. Omic approaches help enhance biorefinery capabilities and are now in the developing stage for algae. The future is very bright for transgenic algae with increased biomass yield, carbon dioxide uptake rate, accumulating high-value compounds, reduction in cultivation, and production costs, thus reaching the goal in the global algal market and capital flow. However, microalgae are primary producers and any harmful exposure to the wild strains can affect the entire ecosystem. Therefore, strict regulation and monitoring are required to assess the potential risks before introducing genetically modified microalgae into the natural ecosystem.
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Affiliation(s)
- Mehmooda Fayyaz
- Department of Chemical and Environmental Engineering, Faculty of Science and Engineering, University of Nottingham Malaysia, Jalan Broga, 43500 Semenyih, Selangor, Malaysia
| | - Kit Wayne Chew
- School of Energy and Chemical Engineering, Xiamen University Malaysia, Jalan Sunsuria, Bandar Sunsuria, 43900 Sepang, Selangor, Malaysia
| | - Pau Loke Show
- Department of Chemical and Environmental Engineering, Faculty of Science and Engineering, University of Nottingham Malaysia, Jalan Broga, 43500 Semenyih, Selangor, Malaysia.
| | - Tau Chuan Ling
- Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - I-Son Ng
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Jo-Shu Chang
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan; Department of Chemical and Materials Engineering, College of Engineering, Tunghai University, Taichung 407, Taiwan; Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung 407, Taiwan.
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Enrichment of f/2 medium hyperaccumulates biomass and bioactive compounds in the diatom Phaeodactylum tricornutum. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101872] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Ryu AJ, Kang NK, Jeon S, Hur DH, Lee EM, Lee DY, Jeong BR, Chang YK, Jeong KJ. Development and characterization of a Nannochloropsis mutant with simultaneously enhanced growth and lipid production. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:38. [PMID: 32158502 PMCID: PMC7057510 DOI: 10.1186/s13068-020-01681-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 02/13/2020] [Indexed: 05/24/2023]
Abstract
BACKGROUND The necessity to develop high lipid-producing microalgae is emphasized for the commercialization of microalgal biomass, which is environmentally friendly and sustainable. Nannochloropsis are one of the best industrial microalgae and have been widely studied for their lipids, including high-value polyunsaturated fatty acids (PUFAs). Many reports on the genetic and biological engineering of Nannochloropsis to improve their growth and lipid contents have been published. RESULTS We performed insertional mutagenesis in Nannochloropsis salina, and screened mutants with high lipid contents using fluorescence-activated cell sorting (FACS). We isolated a mutant, Mut68, which showed improved growth and a concomitant increase in lipid contents. Mut68 exhibited 53% faster growth rate and 34% higher fatty acid methyl ester (FAME) contents after incubation for 8 days, resulting in a 75% increase in FAME productivity compared to that in the wild type (WT). By sequencing the whole genome, we identified the disrupted gene in Mut68 that encoded trehalose-6-phosphate (T6P) synthase (TPS). TPS is composed of two domains: TPS domain and T6P phosphatase (TPP) domain, which catalyze the initial formation of T6P and dephosphorylation to trehalose, respectively. Mut68 was disrupted at the TPP domain in the C-terminal half, which was confirmed by metabolic analyses revealing a great reduction in the trehalose content in Mut68. Consistent with the unaffected N-terminal TPS domain, Mut68 showed moderate increase in T6P that is known for regulation of sugar metabolism, growth, and lipid biosynthesis. Interestingly, the metabolic analyses also revealed a significant increase in stress-related amino acids, including proline and glutamine, which may further contribute to the Mut68 phenotypes. CONCLUSION We have successfully isolated an insertional mutant showing improved growth and lipid production. Moreover, we identified the disrupted gene encoding TPS. Consistent with the disrupted TPP domain, metabolic analyses revealed a moderate increase in T6P and greatly reduced trehalose. Herein, we provide an excellent proof of concept that the selection of insertional mutations via FACS can be employed for the isolation of mutants with improved growth and lipid production. In addition, trehalose and genes encoding TPS will provide novel targets for chemical and genetic engineering, in other microalgae and organisms as well as Nannochloropsis.
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Affiliation(s)
- Ae Jin Ryu
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Advanced Biomass R&D Center (ABC), KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
| | - Nam Kyu Kang
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Present Address: Carl. R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Seungjib Jeon
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Advanced Biomass R&D Center (ABC), KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
| | - Dong Hoon Hur
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
| | - Eun Mi Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826 Republic of Korea
| | - Do Yup Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826 Republic of Korea
| | - Byeong-ryool Jeong
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Present Address: School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919 Korea
- Present Address: Single-Cell Center, Qingdao Institute of BioEnergy and Bioprocess Technology (QIBEBT), Qingdao, 266101 Shandong China
| | - Yong Keun Chang
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Advanced Biomass R&D Center (ABC), KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
| | - Ki Jun Jeong
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
- Institute for the BioCentury, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141 Republic of Korea
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Wang X, Balamurugan S, Liu SF, Zhang MM, Yang WD, Liu JS, Li HY, Lin CSK. Enhanced polyunsaturated fatty acid production using food wastes and biofuels byproducts by an evolved strain of Phaeodactylum tricornutum. BIORESOURCE TECHNOLOGY 2020; 296:122351. [PMID: 31708386 DOI: 10.1016/j.biortech.2019.122351] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 10/27/2019] [Accepted: 10/29/2019] [Indexed: 06/10/2023]
Abstract
This study investigates the prospective of utilizing kitchen wastewater and food wastes, biofuels industry byproducts as alternative water and carbon sources. Kitchen wastewater did not impede cellular growth rate of the evolved Phaeodactylum strain E70, which indicates its potential as an alternative to freshwater resources. Among the organic wastes assessed, food waste hydrolysate significantly increased cell growth. Supplement of crude glycerol in cultivation medium enhances the total fatty acid content. Mixed food waste hydrolysate and crude glycerol remarkably increased both the cell density and total fatty acid content. Also, the supplement of butylated hydroxytoluene alleviated the oxidative stress induced by impurities in organic wastes and concomitantly increased microalgal total fatty acids and polyunsaturated fatty acids content. The experimental results reported in this study show that a waste-based biorefinery could lead to utilization of organic waste resources for the efficient production of value-added products.
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Affiliation(s)
- Xiang Wang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China; School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Srinivasan Balamurugan
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Si-Fen Liu
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Man-Man Zhang
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Wei-Dong Yang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Jie-Sheng Liu
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Hong-Ye Li
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Carol Sze Ki Lin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
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Wang X, Liu SF, Li RY, Yang WD, Liu JS, Lin CSK, Balamurugan S, Li HY. TAG pathway engineering via GPAT2 concurrently potentiates abiotic stress tolerance and oleaginicity in Phaeodactylum tricornutum. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:160. [PMID: 32944076 PMCID: PMC7491103 DOI: 10.1186/s13068-020-01799-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Accepted: 09/04/2020] [Indexed: 05/03/2023]
Abstract
BACKGROUND Despite the great potential of marine diatoms in biofuel sector, commercially viable biofuel production from native diatom strain is impractical. Targeted engineering of TAG pathway represents a promising approach; however, recruitment of potential candidate has been regarded as critical. Here, we identified a glycerol-3-phosphate acyltransferase 2 (GPAT2) isoform and overexpressed in Phaeodactylum tricornutum. RESULTS GPAT2 overexpression did not impair growth and photosynthesis. GPAT2 overexpression reduced carbohydrates and protein content, however, lipid content were significantly increased. Specifically, TAG content was notably increased by 2.9-fold than phospho- and glyco-lipids. GPAT2 overexpression elicited the push-and-pull strategy by increasing the abundance of substrates for the subsequent metabolic enzymes, thereby increased the expression of LPAAT and DGAT. Besides, GPAT2-mediated lipid overproduction coordinated the expression of NADPH biosynthetic genes. GPAT2 altered the fatty acid profile in TAGs with C16:0 as the predominant fatty acid moieties. We further investigated the impact of GPAT2 on conferring abiotic stress, which exhibited enhanced tolerance to hyposaline (70%) and chilling (10 ºC) conditions via altered fatty acid saturation level. CONCLUSIONS Collectively, our results exemplified the critical role of GPAT2 in hyperaccumulating TAGs with altered fatty acid profile, which in turn uphold resistance to abiotic stress conditions.
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Affiliation(s)
- Xiang Wang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Si-Fen Liu
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
| | - Ruo-Yu Li
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
| | - Wei-Dong Yang
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
| | - Jie-Sheng Liu
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
| | - Carol Sze Ki Lin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Srinivasan Balamurugan
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
- Department of Biotechnology, Bharathidasan University, Tiruchirappalli, 620024 India
| | - Hong-Ye Li
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science, Jinan University, Guangzhou, 510632 China
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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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Muñoz CF, Weusthuis RA, D’Adamo S, Wijffels RH. Effect of Single and Combined Expression of Lysophosphatidic Acid Acyltransferase, Glycerol-3-Phosphate Acyltransferase, and Diacylglycerol Acyltransferase on Lipid Accumulation and Composition in Neochloris oleoabundans. FRONTIERS IN PLANT SCIENCE 2019; 10:1573. [PMID: 31850043 PMCID: PMC6895027 DOI: 10.3389/fpls.2019.01573] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 11/11/2019] [Indexed: 05/03/2023]
Abstract
Microalgal lipids are promising feedstocks for food and biofuels. Since lipid production by microalgae is not yet economically feasible, genetic engineering is becoming a promising strategy to achieve higher lipid accumulation and productivities. Enzymes involved in the Kennedy pathway such as glycerol-3-phosphate acyltransferase (GPAT), lysophosphatidic acid acyltransferase (LPAT), and diacylglycerol acyltransferase (DGAT) catalyze key steps in the formation of triacylglycerol, which is the main constituent of lipids in N. oleoabundans. The overexpression of these enzymes in the targeted strain has a great potential to further increase their triacylglycerol content. We overexpressed single and multiple encoding genes for LPAT, GPAT, and DGAT from Acutodesmus obliquus in N. oleoabundans. Strains overexpressing single genes produced up to 52% and 45% g · gDW-1, which corresponds to 1.3- and 1.4-fold increase in total fatty acids and triacylglycerols, respectively. The orchestrated expression of the three genes resulted in 49% and 39% g · gDW-1, which is 1.2-folds increase in total fatty acids and triacylglycerols. Single expression of LPAT, GPAT, and DGAT genes resulted in higher lipid productivities during starvation without a significant effect on growth and photosynthetic activity during replete conditions. On the other hand, the simultaneous expression of LPAT, GPAT, and DGAT genes resulted in 52% lower growth rate, 14% lower photosynthetic activity and 4-folds increase in cell diameter. Moreover, the multigene expressing line showed a decrease in carbohydrates and protein content and an increase in pigments during nitrogen starved condition. The single and multiple expression of heterologous genes LPAT, GPAT, and DGAT showed to significantly enhanced the lipid accumulation in N. oleoabundans. Single gene expression resulted in higher lipid production and productivities without having a significant impact in the physiological status of the strains. This approach shows the potential for the generation of microalgal strains with higher economical potential for the production of lipids.
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Affiliation(s)
- Camilo F. Muñoz
- Bioprocess Engineering, Wageningen University and Research, Wageningen, Netherlands
- *Correspondence: Camilo F. Muñoz,
| | - Ruud A. Weusthuis
- Bioprocess Engineering, Wageningen University and Research, Wageningen, Netherlands
| | - Sarah D’Adamo
- Bioprocess Engineering, Wageningen University and Research, Wageningen, Netherlands
| | - René H. Wijffels
- Bioprocess Engineering, Wageningen University and Research, Wageningen, Netherlands
- Biosciences and Aquaculture, Nord University, Bodø, Norway
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