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Abdullah M, Ali Z, Yasin MT, Amanat K, Sarwar F, Khan J, Ahmad K. Advancements in sustainable production of biofuel by Microalgae: Recent insights and future directions. ENVIRONMENTAL RESEARCH 2024:119902. [PMID: 39222730 DOI: 10.1016/j.envres.2024.119902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 08/27/2024] [Accepted: 08/30/2024] [Indexed: 09/04/2024]
Abstract
Microalgae is considered as sustainable and viable feedstock for biofuel production due to its significant advantages over terrestrial plants. Algal biofuels have received significant attention among researchers and energy experts owing to an upsurge in global energy issues emanating from depletion in fossil fuel reserves increasing greenhouse gases emission conflict among agricultural crops, traditional biomass feedstock, and potential futuristic energy security. Further, the exploration of value-added microalgae as sustainable and viable feedstock for the production of variety of biofuels such as biogas, bio-hydrogen, bioethanol, and biodiesel are addressed. Moreover, the assessment of life-cycle, energy balance, and environmental impacts of biofuel production from microalgae are briefly discussed. The present study focused on recent advancements in synthetic biology, metabolic engineering tools, algal bio refinery, and the optimization of algae growth conditions. This paper also elucidates the function of microalgae as bio refineries, the conditions of algae-based cultures, and other operational factors that must be adjusted to produce biofuels that are price-competitive with fossil fuels.
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Affiliation(s)
- Muhammad Abdullah
- Institute of Biological Sciences, Khwaja Fareed University of Engineering & Information Technology, 64200 Rahim Yar Khan, Pakistan
| | - Zain Ali
- Institute of Biological Sciences, Khwaja Fareed University of Engineering & Information Technology, 64200 Rahim Yar Khan, Pakistan
| | - Muhammad Talha Yasin
- Institute of Biological Sciences, Khwaja Fareed University of Engineering & Information Technology, 64200 Rahim Yar Khan, Pakistan.
| | - Kinza Amanat
- Institute of Biological Sciences, Khwaja Fareed University of Engineering & Information Technology, 64200 Rahim Yar Khan, Pakistan
| | - Fatima Sarwar
- Institute of Chemistry, Khwaja Fareed University of Engineering & Information Technology, 64200 Rahim Yar Khan, Pakistan
| | - Jallat Khan
- Institute of Biological Sciences, Khwaja Fareed University of Engineering & Information Technology, 64200 Rahim Yar Khan, Pakistan; Institute of Chemistry, Khwaja Fareed University of Engineering & Information Technology, 64200 Rahim Yar Khan, Pakistan
| | - Khurshid Ahmad
- State Key Laboratory of Marine Food Processing & Safety Control, College of Food Science and Engineering, Ocean University of China, No.1299, Sansha Road, Qingdao, Shandong Province, 266404, P.R. China
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2
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Tong Y, Li Y, Qin W, Wu S, Xu W, Jin P, Zheng Z. New insight into the metabolic mechanism of a novel lipid-utilizing and denitrifying bacterium capable of simultaneous removal of nitrogen and grease through transcriptome analysis. Front Microbiol 2023; 14:1258003. [PMID: 37965562 PMCID: PMC10642853 DOI: 10.3389/fmicb.2023.1258003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 10/17/2023] [Indexed: 11/16/2023] Open
Abstract
Introduction Issues related to fat, oil, and grease from kitchen waste (KFOG) in lipid-containing wastewater are intensifying globally. We reported a novel denitrifying bacterium Pseudomonas CYCN-C with lipid-utilizing activity and high nitrogen-removal efficiency. The aim of the present study was aim to explore the metabolic mechanism of the simultaneous lipid-utilizing and denitrifying bacterium CYCN-C at transcriptome level. Methods We comparatively investigated the cell-growth and nitrogen-removal performances of newly reported Pseudomonas glycinae CYCN-C under defined cultivation conditions. Transcriptome analysis was further used to investigate all pathway genes involved in nitrogen metabolism, lipid degradation and utilization, and cell growth at mRNA levels. Results CYCN-C could directly use fat, oil, and grease from kitchen waste (KFOG) as carbon source with TN removal efficiency of 73.5%, significantly higher than that (60.9%) with sodium acetate. The change levels of genes under defined KFOG and sodium acetate were analyzed by transcriptome sequencing. Results showed that genes cyo, CsrA, PHAs, and FumC involved in carbon metabolism under KFOG were significantly upregulated by 6.9, 0.7, 26.0, and 19.0-folds, respectively. The genes lipA, lipB, glpD, and glpK of lipid metabolic pathway were upregulated by 0.6, 0.4, 21.5, and 1.3-folds, respectively. KFOG also improved the denitrification efficiency by inducing the expression of the genes nar, nirB, nirD, and norR of denitrification pathways. Conclusion In summary, this work firstly provides valuable insights into the genes expression of lipid-utilizing and denitrifying bacterium, and provides a new approach for sewage treatment with reuse of KFOG wastes.
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Affiliation(s)
- Yaobin Tong
- School of Environmental & Resource, Zhejiang A & F University, Hangzhou, China
| | - Yiyi Li
- Zhejiang Sunda Public Environmental Protection Co., Ltd., Hangzhou, China
| | - Wenpan Qin
- Zhejiang Sunda Public Environmental Protection Co., Ltd., Hangzhou, China
| | - Shengchun Wu
- School of Environmental & Resource, Zhejiang A & F University, Hangzhou, China
- Zhejiang Sunda Public Environmental Protection Co., Ltd., Hangzhou, China
| | - Weiping Xu
- Zhejiang Sunda Public Environmental Protection Co., Ltd., Hangzhou, China
| | - Peng Jin
- College of Food and Health, Zhejiang A & F University, Hangzhou, China
| | - Zhanwang Zheng
- School of Environmental & Resource, Zhejiang A & F University, Hangzhou, China
- Zhejiang Sunda Public Environmental Protection Co., Ltd., Hangzhou, China
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3
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Becker J, Liebal UW, Phan AN, Ullmann L, Blank LM. Renewable carbon sources to biochemicals and -fuels: contributions of the smut fungi Ustilaginaceae. Curr Opin Biotechnol 2023; 79:102849. [PMID: 36446145 DOI: 10.1016/j.copbio.2022.102849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/27/2022] [Accepted: 11/01/2022] [Indexed: 11/27/2022]
Abstract
The global demand for food, fuels, and chemicals increases annually. Using renewable C-sources (i.e. biomass, CO2, and organic waste) is a prerequisite for a future free of fossil carbon. The smut fungi Ustilaginaceae naturally produce a versatile spectrum of valuable products, such as organic acids, polyols, and glycolipids, applicable in the food, energy, chemistry, and pharmaceutical sector. Combined with the use of alternative (co-)substrates (e.g. acetate, butanediol, formate, and glycerol), these microorganisms offer excellent potential for industrial biotechnology, thereby overcoming central challenges humankind faces, including CO2 release and land use. Here, we provide insight into fundamental production capacities, present genetic modifications that improve the biotechnical application, and review recent high-performance engineering of Ustilaginaceae toward relevant platform chemicals.
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Affiliation(s)
- Johanna Becker
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Ulf W Liebal
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - An Nt Phan
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Lena Ullmann
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Lars M Blank
- iAMB - Institute of Applied Microbiology, ABBt - Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany.
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Expression profile of genes associated with the accumulation of triacylglycerol (TAG) in Auxenochlorella protothecoides KP7 under alkaline pH and nitrogen starvation conditions. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2023. [DOI: 10.1016/j.bcab.2023.102628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Cao Y, Li Q, Zhang L. The core triacylglycerol toolbox in woody oil plants reveals targets for oil production bioengineering. FRONTIERS IN PLANT SCIENCE 2023; 14:1170723. [PMID: 37077641 PMCID: PMC10106636 DOI: 10.3389/fpls.2023.1170723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 03/21/2023] [Indexed: 05/03/2023]
Abstract
Woody oil plants are the most productive oil-bearing species that produce seeds with high levels of valuable triacylglycerols (TAGs). TAGs and their derivatives are the raw materials for many macromolecular bio-based products, such as nylon precursors, and biomass-based diesel. Here, we identified 280 genes encoding seven distinct classes of enzymes (i.e., G3PAT, LPAAT, PAP, DGAT, PDCT, PDAT, and CPT) involved in TAGs-biosynthesis. Several multigene families are expanded by large-scale duplication events, such as G3PATs, and PAPs. RNA-seq was used to survey the expression profiles of these TAG pathway-related genes in different tissues or development, indicating functional redundancy for some duplicated genes originated from the large-scale duplication events, and neo-functionalization or sub-functionalization for some of them. Sixty-two genes showed strong, preferential expression during the period of rapid seed lipid synthesis, suggesting that their might represented the core TAG-toolbox. We also revealed for the first time that there is no PDCT pathway in Vernicia fordii and Xanthoceras sorbifolium. The identification of key genes involved in lipid biosynthesis will be the foundation to plan strategies to develop woody oil plant varieties with enhanced processing properties and high oil content.
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Affiliation(s)
- Yunpeng Cao
- School of Health and Nursing, Wuchang University of Technology, Wuhan, China
- Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- College of Forestry, Central South University of Forestry and Technology, Changsha, Hunan, China
- *Correspondence: Yunpeng Cao, ; Lin Zhang,
| | - Qiang Li
- School of Health and Nursing, Wuchang University of Technology, Wuhan, China
| | - Lin Zhang
- College of Basic Medical Sciences, Hubei University of Chinese Medicine, Wuhan, China
- *Correspondence: Yunpeng Cao, ; Lin Zhang,
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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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Kumar L, Mohan L, Anand R, Joshi V, Chugh M, Bharadvaja N. A review on unit operations, challenges, opportunities, and strategies to improve algal based biodiesel and biorefinery. FRONTIERS IN CHEMICAL ENGINEERING 2022. [DOI: 10.3389/fceng.2022.998289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Globally, the demand for energy is increasing with an emphasis on green fuels for a sustainable future. As the urge for alternative fuels is accelerating, microalgae have emerged as a promising source that can not only produce high lipid but many other platform chemicals. Moreover, it is a better alternative in comparison to conventional feedstock due to yearlong easy and mass cultivation, carbon fixation, and value-added products extraction. To date, numerous studies have been done to elucidate these organisms for large-scale fuel production. However, enhancing the lipid synthesis rate and reducing the production cost still remain a major bottleneck for its economic viability. Therefore, this study compiles information on algae-based biodiesel production with an emphasis on its unit operations from strain selection to biofuel production. Additionally, strategies to enhance lipid accumulation by incorporating genetic, and metabolic engineering and the use of leftover biomass for harnessing bio-products have been discussed. Besides, implementing a biorefinery for extracting oil followed by utilizing leftover biomass to generate value-added products such as nanoparticles, biofertilizers, biochar, and biopharmaceuticals has also been discussed.
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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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Santin A, Russo MT, Ferrante MI, Balzano S, Orefice I, Sardo A. Highly Valuable Polyunsaturated Fatty Acids from Microalgae: Strategies to Improve Their Yields and Their Potential Exploitation in Aquaculture. Molecules 2021; 26:7697. [PMID: 34946780 PMCID: PMC8707597 DOI: 10.3390/molecules26247697] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/14/2021] [Accepted: 12/15/2021] [Indexed: 11/16/2022] Open
Abstract
Microalgae have a great potential for the production of healthy food and feed supplements. Their ability to convert carbon into high-value compounds and to be cultured in large scale without interfering with crop cultivation makes these photosynthetic microorganisms promising for the sustainable production of lipids. In particular, microalgae represent an alternative source of polyunsaturated fatty acids (PUFAs), whose consumption is related to various health benefits for humans and animals. In recent years, several strategies to improve PUFAs' production in microalgae have been investigated. Such strategies include selecting the best performing species and strains and the optimization of culturing conditions, with special emphasis on the different cultivation systems and the effect of different abiotic factors on PUFAs' accumulation in microalgae. Moreover, developments and results obtained through the most modern genetic and metabolic engineering techniques are described, focusing on the strategies that lead to an increased lipid production or an altered PUFAs' profile. Additionally, we provide an overview of biotechnological applications of PUFAs derived from microalgae as safe and sustainable organisms, such as aquafeed and food ingredients, and of the main techniques (and their related issues) for PUFAs' extraction and purification from microalgal biomass.
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Affiliation(s)
- Anna Santin
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
| | - Monia Teresa Russo
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
| | - Maria Immacolata Ferrante
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
| | - Sergio Balzano
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
- Department of Marine Microbiology and Biogeochemistry, Netherland Institute for Sea Research, Landsdiep 4, 1793 AB Texel, The Netherlands
| | - Ida Orefice
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
| | - Angela Sardo
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy; (A.S.); (M.T.R.); (S.B.); (I.O.)
- Istituto di Scienze Applicate e Sistemi Intelligenti “Eduardo Caianiello”, Via Campi Flegrei 34, 80078 Pozzuoli, Italy
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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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12
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Brar A, Kumar M, Soni T, Vivekanand V, Pareek N. Insights into the genetic and metabolic engineering approaches to enhance the competence of microalgae as biofuel resource: A review. BIORESOURCE TECHNOLOGY 2021; 339:125597. [PMID: 34315089 DOI: 10.1016/j.biortech.2021.125597] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/13/2021] [Accepted: 07/14/2021] [Indexed: 06/13/2023]
Abstract
Conventional fuel resources are overburden with speedy global energy demand which ensued the urgent need of alternate energy resources. Biofuel generation efficiency of microalgae is notable due to their comparatively rapid biomass production rate and high oil content. But, the employment of microalgae as biofuel resource is in infancy due to low productivity and high production cost. The issues can be addressed by employing engineered microalgal strains that would be able to efficiently generate enhanced levels of biomass with augmented lipid and/or carbohydrate content for proficient biofuel production. Genetic alterations and metabolic engineering of microalgal species might be helpful in developing high stress-tolerant strains with improved properties for biofuel generation. Various omics approaches appeared significant to upgrade the microalgal lipid production. Intervention of genetic and metabolic engineering approaches would facilitate the development of microalgae as a competent biofuel resource and inflate the economic commercialization of biofuels.
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Affiliation(s)
- Amandeep Brar
- Microbial Catalysis and Process Engineering Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, Rajasthan 305817, India
| | - Manish Kumar
- Microbial Catalysis and Process Engineering Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, Rajasthan 305817, India
| | - Twinkle Soni
- Microbial Catalysis and Process Engineering Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, Rajasthan 305817, India
| | - V Vivekanand
- Centre for Energy and Environment, Malaviya National Institute of Technology, Jaipur, Rajasthan 302017, India
| | - Nidhi Pareek
- Microbial Catalysis and Process Engineering Laboratory, Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, Rajasthan 305817, India.
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13
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Gupta A, Barrow CJ, Puri M. Multiproduct biorefinery from marine thraustochytrids towards a circular bioeconomy. Trends Biotechnol 2021; 40:448-462. [PMID: 34627647 DOI: 10.1016/j.tibtech.2021.09.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 09/08/2021] [Accepted: 09/09/2021] [Indexed: 12/18/2022]
Abstract
Microalgal biotechnology research continues to expand due to largely unexplored marine environments and growing consumer interest in healthy products. Thraustochytrids, which are marine oleaginous protists, are known for their production of bioactives with significant applications in nutraceuticals, pharmaceuticals, and aquaculture. A wide range of high-value biochemicals, such as nutritional supplements (omega-3 fatty acids), squalene, exopolysaccharides (EPSs), enzymes, aquaculture feed, and biodiesel and pigment compounds, have been investigated. We discuss thraustochytrids as potential feedstocks to produce various bioactive compounds and advocate developing a biorefinery to offset production costs. We anticipate that future advances in cell manufacturing, lipidomic analysis, and nanotechnology-guided lipid extraction would facilitate large-scale cost-competitive production through these microbes.
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Affiliation(s)
- Adarsha Gupta
- Medical Biotechnology, College of Medicine and Public Health, Flinders University, Bedford Park, 5042, Adelaide, Australia; Flinders Health and Medical Research Institute (FHMRI), Flinders University, Bedford Park, 5042, Adelaide, Australia
| | - Colin J Barrow
- Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, 3216, Geelong, Australia
| | - Munish Puri
- Medical Biotechnology, College of Medicine and Public Health, Flinders University, Bedford Park, 5042, Adelaide, Australia; Flinders Health and Medical Research Institute (FHMRI), Flinders University, Bedford Park, 5042, Adelaide, Australia; Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, 3216, Geelong, Australia.
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Nayar S. Exploring the Role of a Cytokinin-Activating Enzyme LONELY GUY in Unicellular Microalga Chlorella variabilis. FRONTIERS IN PLANT SCIENCE 2021; 11:611871. [PMID: 33613586 PMCID: PMC7891180 DOI: 10.3389/fpls.2020.611871] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 12/14/2020] [Indexed: 05/29/2023]
Abstract
LONELY GUY has been previously characterized in flowering plants to be involved in the direct activation of cytokinins. In this study, the function of the only LONELY GUY gene (CvarLOG1) from unicellular green microalga Chlorella variabilis NC64A has been investigated. CvarLOG1 expressed mainly in the lag and log phases of growth and was confirmed to be a cytokinin-activating enzyme. Overexpression of CvarLOG1 in Chlorella led to extended life in culture by almost 10-20 days, creating a "stay-green" phenotype. In the transformed alga, the cell cycle was lengthened due to delayed entry into the G2/M phase contrary to the known role of cytokinins in stimulating G2/M transition possibly due to excessive levels of this hormone. However, due to the sustained growth and delayed senescence, there was an increase in cell number by 11% and in biomass by 46% at the stationary phase, indicating a potential application for the biofuel industry. The total carbohydrate and lipid yield increased by approximately 30 and 20%, respectively. RNA-Seq-based transcriptomic analysis revealed that the genes associated with light and dark reactions of photosynthesis were upregulated, which may be the reason for the increased biomass. These data show that LOG plays an essential role during the cell cycle and in the functioning of the chloroplast and that the pathway leading to direct activation of cytokinins via LOG is functional in algae.
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Improving ‘Lipid Productivity’ in Microalgae by Bilateral Enhancement of Biomass and Lipid Contents: A Review. SUSTAINABILITY 2020. [DOI: 10.3390/su12219083] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Microalgae have received widespread interest owing to their potential in biofuel production. However, economical microalgal biomass production is conditioned by enhancing the lipid accumulation without decreasing growth rate or by increasing both simultaneously. While extensive investigation has been performed on promoting the economic feasibility of microalgal-based biofuel production that aims to increase the productivity of microalgae species, only a handful of them deal with increasing lipid productivity (based on lipid contents and growth rate) in the feedstock production process. The purpose of this review is to provide an overview of the recent advances and novel approaches in promoting lipid productivity (depends on biomass and lipid contents) in feedstock production from strain selection to after-harvesting stages. The current study comprises two parts. In the first part, bilateral improving biomass/lipid production will be investigated in upstream measures, including strain selection, genetic engineering, and cultivation stages. In the second part, the enhancement of lipid productivity will be discussed in the downstream measure included in the harvesting and after-harvesting stages. An integrated approach involving the strategies for increasing lipid productivity in up- and down-stream measures can be a breakthrough approach that would promote the commercialization of market-driven microalgae-derived biofuel production.
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Kumar G, Shekh A, Jakhu S, Sharma Y, Kapoor R, Sharma TR. Bioengineering of Microalgae: Recent Advances, Perspectives, and Regulatory Challenges for Industrial Application. Front Bioeng Biotechnol 2020; 8:914. [PMID: 33014997 PMCID: PMC7494788 DOI: 10.3389/fbioe.2020.00914] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 07/15/2020] [Indexed: 01/14/2023] Open
Abstract
Microalgae, due to their complex metabolic capacity, are being continuously explored for nutraceuticals, pharmaceuticals, and other industrially important bioactives. However, suboptimal yield and productivity of the bioactive of interest in local and robust wild-type strains are of perennial concerns for their industrial applications. To overcome such limitations, strain improvement through genetic engineering could play a decisive role. Though the advanced tools for genetic engineering have emerged at a greater pace, they still remain underused for microalgae as compared to other microorganisms. Pertaining to this, we reviewed the progress made so far in the development of molecular tools and techniques, and their deployment for microalgae strain improvement through genetic engineering. The recent availability of genome sequences and other omics datasets form diverse microalgae species have remarkable potential to guide strategic momentum in microalgae strain improvement program. This review focuses on the recent and significant improvements in the omics resources, mutant libraries, and high throughput screening methodologies helpful to augment research in the model and non-model microalgae. Authors have also summarized the case studies on genetically engineered microalgae and highlight the opportunities and challenges that are emerging from the current progress in the application of genome-editing to facilitate microalgal strain improvement. Toward the end, the regulatory and biosafety issues in the use of genetically engineered microalgae in commercial applications are described.
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Affiliation(s)
- Gulshan Kumar
- Agricultural Biotechnology Division, National Agri-Food Biotechnology Institute (NABI), Sahibzada Ajit Singh Nagar, India
| | - Ajam Shekh
- Plant Cell Biotechnology Department, CSIR-Central Food Technological Research Institute (CFTRI), Mysuru, India
| | - Sunaina Jakhu
- Agricultural Biotechnology Division, National Agri-Food Biotechnology Institute (NABI), Sahibzada Ajit Singh Nagar, India
| | - Yogesh Sharma
- Agricultural Biotechnology Division, National Agri-Food Biotechnology Institute (NABI), Sahibzada Ajit Singh Nagar, India
| | - Ritu Kapoor
- Agricultural Biotechnology Division, National Agri-Food Biotechnology Institute (NABI), Sahibzada Ajit Singh Nagar, India
| | - Tilak Raj Sharma
- Division of Crop Science, Indian Council of Agricultural Research, New Delhi, India
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Sahoo S, Mahapatra SR, Das N, Parida BK, Rath S, Misra N, Suar M. Functional elucidation of hypothetical proteins associated with lipid accumulation: Prioritizing genetic engineering targets for improved algal biofuel production. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101887] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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18
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Rendón-Castrillón L, Ramírez-Carmona M, Ocampo-López C, Giraldo-Aristizabal R. Evaluation of the operational conditions in the production and morphology of Chlorella sp. BRAZ J BIOL 2020; 81:202-209. [PMID: 32130288 DOI: 10.1590/1519-6984.228874] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 10/01/2019] [Indexed: 11/22/2022] Open
Abstract
It was evaluated the effect of operational conditions in the production of Chlorella sp. after its selection from genus Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. and Dunaliella salina. Microalgae were inoculated in drinking water with addition of NPK fertilizer (N 24%, P 24%, K 18%), at a concentration of 0.5 g/L, agitation of 150 rpm, temperature 25 °C, light intensity of 1680 lumens at a color temperature of 6400K, without pH control for 8 days. The cellular concentrations obtained were 3.72x107 (Chlorella sp.), 1.36x107 (Scenedesmus sp.), 3.55x107 (Tetraselmis sp.), 5.74x107 (Nannochloris sp.) and 3.45x106 (Dunaliella salina), where the microalgae Chlorella sp., shows invasive capacity in drinking water cultivations. Applying the 2n-p fractional factorial design concept for the elemental composition of the microalgae and the cellular morphology, it was obtained 44.33% of C, 7.09% of H, 8.53% of N and 0.84% of S for the Chlorella sp.
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Affiliation(s)
- L Rendón-Castrillón
- Centro de Estudios y de Investigación en Biotecnología - CIBIOT, Facultad de Ingeniería Química, Universidad Pontificia Bolivariana, Cir. 1ª #70-01, of. Bloque 11-116, Medellín, Colombia
| | - M Ramírez-Carmona
- Centro de Estudios y de Investigación en Biotecnología - CIBIOT, Facultad de Ingeniería Química, Universidad Pontificia Bolivariana, Cir. 1ª #70-01, of. Bloque 11-116, Medellín, Colombia
| | - C Ocampo-López
- Centro de Estudios y de Investigación en Biotecnología - CIBIOT, Facultad de Ingeniería Química, Universidad Pontificia Bolivariana, Cir. 1ª #70-01, of. Bloque 11-116, Medellín, Colombia
| | - R Giraldo-Aristizabal
- Centro de Estudios y de Investigación en Biotecnología - CIBIOT, Facultad de Ingeniería Química, Universidad Pontificia Bolivariana, Cir. 1ª #70-01, of. Bloque 11-116, Medellín, Colombia
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Shahid A, Rehman AU, Usman M, Ashraf MUF, Javed MR, Khan AZ, Gill SS, Mehmood MA. Engineering the metabolic pathways of lipid biosynthesis to develop robust microalgal strains for biodiesel production. Biotechnol Appl Biochem 2020; 67:41-51. [DOI: 10.1002/bab.1812] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 09/03/2019] [Indexed: 01/29/2023]
Affiliation(s)
- Ayesha Shahid
- Bioenergy Research CenterDepartment of Bioinformatics and BiotechnologyGovernment College University Faisalabad Faisalabad Pakistan
| | - Abd ur Rehman
- Bioenergy Research CenterDepartment of Bioinformatics and BiotechnologyGovernment College University Faisalabad Faisalabad Pakistan
| | - Muhammad Usman
- Bioenergy Research CenterDepartment of Bioinformatics and BiotechnologyGovernment College University Faisalabad Faisalabad Pakistan
| | - Muhammad Umer Farooq Ashraf
- Bioenergy Research CenterDepartment of Bioinformatics and BiotechnologyGovernment College University Faisalabad Faisalabad Pakistan
| | - Muhammad Rizwan Javed
- Bioenergy Research CenterDepartment of Bioinformatics and BiotechnologyGovernment College University Faisalabad Faisalabad Pakistan
| | - Aqib Zafar Khan
- State Key Laboratory of Microbial MetabolismJoint International Research Laboratory of Metabolic & Developmental Sciences of Ministry of Education, School of Life Science and BiotechnologyShanghai Jiao Tong University Shanghai People's Republic of China
| | - Saba Shahid Gill
- Department of Plant and Environmental SciencesNew Mexico State University Las Cruces NM USA
| | - Muhammad Aamer Mehmood
- Bioenergy Research CenterDepartment of Bioinformatics and BiotechnologyGovernment College University Faisalabad Faisalabad Pakistan
- School of BioengineeringSichuan University of Science & Engineering Zigong People's Republic of China
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20
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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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Abstract
Microalgae are unicellular organisms that act as the crucial primary producers all over the world, typically found in marine and freshwater environments. Most of them can live photo-autotrophically, reproduce rapidly, and accumulate biomass in a short period efficiently. To adapt to the uninterrupted change of the environment, they evolve and differentiate continuously. As a result, some of them evolve special abilities such as toleration of extreme environment, generation of sophisticated structure to adapt to the environment, and avoid predators. Microalgae are believed to be promising bioreactors because of their high lipid and pigment contents. Genetic engineering technologies have given revolutions in the microalgal industry, which decoded the secrets of microalgal genes, express recombinant genes in microalgal genomes, and largely soar the accumulation of interested components in transgenic microalgae. However, owing to several obstructions, the industry of transgenic microalgae is still immature. Here, we provide an overview to emphasize the advantage and imperfection of the existing transgenic microalgal bioreactors.
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Affiliation(s)
- Zhi-Cong Liang
- College of Food Science and Engineering, South China University of Technology, Guangzhou, China
| | - Ming-Hua Liang
- College of Food Science and Engineering, South China University of Technology, Guangzhou, China
| | - Jian-Guo Jiang
- College of Food Science and Engineering, South China University of Technology, Guangzhou, China
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22
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Biomass and lipid induction strategies in microalgae for biofuel production and other applications. Microb Cell Fact 2019; 18:178. [PMID: 31638987 PMCID: PMC6805540 DOI: 10.1186/s12934-019-1228-4] [Citation(s) in RCA: 119] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/04/2019] [Indexed: 11/20/2022] Open
Abstract
The use of fossil fuels has been strongly related to critical problems currently affecting society, such as: global warming, global greenhouse effects and pollution. These problems have affected the homeostasis of living organisms worldwide at an alarming rate. Due to this, it is imperative to look for alternatives to the use of fossil fuels and one of the relevant substitutes are biofuels. There are different types of biofuels (categories and generations) that have been previously explored, but recently, the use of microalgae has been strongly considered for the production of biofuels since they present a series of advantages over other biofuel production sources: (a) they don’t need arable land to grow and therefore do not compete with food crops (like biofuels produced from corn, sugar cane and other plants) and; (b) they exhibit rapid biomass production containing high oil contents, at least 15 to 20 times higher than land based oleaginous crops. Hence, these unicellular photosynthetic microorganisms have received great attention from researches to use them in the large-scale production of biofuels. However, one disadvantage of using microalgae is the high economic cost due to the low-yields of lipid content in the microalgae biomass. Thus, development of different methods to enhance microalgae biomass, as well as lipid content in the microalgae cells, would lead to the development of a sustainable low-cost process to produce biofuels. Within the last 10 years, many studies have reported different methods and strategies to induce lipid production to obtain higher lipid accumulation in the biomass of microalgae cells; however, there is not a comprehensive review in the literature that highlights, compares and discusses these strategies. Here, we review these strategies which include modulating light intensity in cultures, controlling and varying CO2 levels and temperature, inducing nutrient starvation in the culture, the implementation of stress by incorporating heavy metal or inducing a high salinity condition, and the use of metabolic and genetic engineering techniques coupled with nanotechnology.
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23
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Sun XM, Ren LJ, Zhao QY, Ji XJ, Huang H. Enhancement of lipid accumulation in microalgae by metabolic engineering. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:552-566. [DOI: 10.1016/j.bbalip.2018.10.004] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 07/30/2018] [Accepted: 10/05/2018] [Indexed: 01/08/2023]
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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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Naghshbandi MP, Tabatabaei M, Aghbashlo M, Aftab MN, Iqbal I. Metabolic Engineering of Microalgae for Biofuel Production. Methods Mol Biol 2019; 1980:153-172. [PMID: 30666564 DOI: 10.1007/7651_2018_205] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Microalgae are considered as promising cell factories for the production of various types of biofuels, including bioethanol, biodiesel, and biohydrogen by using carbon dioxide and sunlight. In spite of unique advantages of these microorganisms, the commercialization of microalgal biofuels has been hindered by poor economic features. Metabolic engineering is among the most promising strategies put forth to overcome this challenge. In this chapter, metabolic pathways involved in lipid and hydrogen production by microalgae are reviewed and discussed. Moreover, metabolic and genetic engineering approaches investigated for improving the rate of lipid (as a feedstock for biodiesel production) and biohydrogen synthesis are presented. Finally, genetic engineering tools and approaches employed for engineering microalgal metabolic pathways are elaborated. A thorough step-by-step protocol for reconstructing the metabolic pathway of various microorganisms including microalgae is also presented.
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Affiliation(s)
- Mohammad Pooya Naghshbandi
- Department of Microbial Biotechnology, School of Biology, College of Science, University of Tehran, Tehran, Iran
| | - Meisam Tabatabaei
- Microbial Biotechnology Department, Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research, Education, and Extension Organization (AREEO), Karaj, Iran. .,Biofuel Research Team (BRTeam), Karaj, Iran.
| | - Mortaza Aghbashlo
- Department of Mechanical Engineering of Agricultural Machinery, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.
| | - Muhammad Nauman Aftab
- Institute of Industrial Biotechnology, Government College University, Lahore, Pakistan
| | - Irfana Iqbal
- Department of Zoology, Lahore College for Women University, Lahore, Pakistan
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Xue J, Chen TT, Zheng JW, Balamurugan S, Cai JX, Liu YH, Yang WD, Liu JS, Li HY. The role of diatom glucose-6-phosphate dehydrogenase on lipogenic NADPH supply in green microalgae through plastidial oxidative pentose phosphate pathway. Appl Microbiol Biotechnol 2018; 102:10803-10815. [PMID: 30349933 DOI: 10.1007/s00253-018-9415-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 08/23/2018] [Accepted: 09/20/2018] [Indexed: 11/27/2022]
Abstract
Commercial production of biofuel from oleaginous microalgae is often impeded by their slow growth rate than other fast-growing algal species. A promising strategy is to genetically engineer the fast-growing algae to accumulate lipids by expressing key lipogenic genes from oleaginous microalgae. However, lacking of strong expression cassette to transform most of the algal species and potential metabolic target to engineer lipid metabolism has hindered its biotechnological applications. In this study, we engineered the oxidative pentose phosphate pathway (PPP) of green microalga Chlorella pyrenoidosa for lipid enhancement by expressing a glucose-6-phosphate dehydrogenase (G6PD) from oleaginous diatom Phaeodactylum tricornutum. Molecular characterization of transformed lines revealed that heterologous PtG6PD was transcribed and expressed successfully. Interestingly, subcellular localization analyses revealed that PtG6PD was targeted to chloroplasts of C. pyrenoidosa. PtG6PD expression remarkably elevated NADPH content and consequently enhanced the lipid content without affecting growth rate. Collectively, this report represents a promising candidate to engineer lipid biosynthesis in heterologous hosts with notable commercial significance, and it highlights the potential role of plastidial PPP in supplying lipogenic NADPH in microalgae.
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Affiliation(s)
- Jiao Xue
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Ting-Ting Chen
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Jian-Wei 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
| | - Srinivasan Balamurugan
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Jia-Xi Cai
- Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China
| | - Yu-Hong 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
| | - 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
| | - Jie-Sheng 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
| | - 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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Wase N, Black P, DiRusso C. Innovations in improving lipid production: Algal chemical genetics. Prog Lipid Res 2018; 71:101-123. [DOI: 10.1016/j.plipres.2018.07.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 06/25/2018] [Accepted: 07/06/2018] [Indexed: 01/01/2023]
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de Jaeger L, Carreres BM, Springer J, Schaap PJ, Eggink G, Martins Dos Santos VAP, Wijffels RH, Martens DE. Neochloris oleoabundans is worth its salt: Transcriptomic analysis under salt and nitrogen stress. PLoS One 2018; 13:e0194834. [PMID: 29652884 PMCID: PMC5898717 DOI: 10.1371/journal.pone.0194834] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 03/09/2018] [Indexed: 11/19/2022] Open
Abstract
Neochloris oleoabundans is an oleaginous microalgal species that can be cultivated in fresh water as well as salt water. Using salt water gives the opportunity to reduce production costs and the fresh water footprint for large scale cultivation. Production of triacylglycerols (TAG) usually includes a biomass growth phase in nitrogen-replete conditions followed by a TAG accumulation phase under nitrogen-deplete conditions. This is the first report that provides insight in the saline resistance mechanism of a fresh water oleaginous microalgae. To better understand the osmoregulatory mechanism of N. oleoabundans during growth and TAG accumulating conditions, the transcriptome was sequenced under four different conditions: fresh water nitrogen-replete and -deplete conditions, and salt water (525 mM dissolved salts, 448mM extra NaCl) nitrogen-replete and -deplete conditions. In this study, several pathways are identified to be responsible for salt water adaptation of N. oleoabundans under both nitrogen-replete and -deplete conditions. Proline and the ascorbate-glutathione cycle seem to be of importance for successful osmoregulation in N. oleoabundans. Genes involved in Proline biosynthesis were found to be upregulated in salt water. This was supported by Nuclear magnetic resonance (NMR) spectroscopy, which indicated an increase in proline content in the salt water nitrogen-replete condition. Additionally, the lipid accumulation pathway was studied to gain insight in the gene regulation in the first 24 hours after nitrogen was depleted. Oil accumulation is increased under nitrogen-deplete conditions in a comparable way in both fresh and salt water. The mechanism behind the biosynthesis of compatible osmolytes can be used to improve N. oleoabundans and other industrially relevant microalgal strains to create a more robust and sustainable production platform for microalgae derived products in the future.
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Affiliation(s)
- Lenny de Jaeger
- Bioprocess Engineering and AlgaePARC, Wageningen University & Research, Wageningen, The Netherlands
| | - Benoit M. Carreres
- Laboratory of Systems and Synthetic Biology, Wageningen University & Research, Wageningen, The Netherlands
| | - Jan Springer
- Food and Biobased Research and AlgaePARC, Wageningen University & Research, Wageningen, The Netherlands
| | - Peter J. Schaap
- Laboratory of Systems and Synthetic Biology, Wageningen University & Research, Wageningen, The Netherlands
| | - Gerrit Eggink
- Bioprocess Engineering and AlgaePARC, Wageningen University & Research, Wageningen, The Netherlands
- Food and Biobased Research and AlgaePARC, Wageningen University & Research, Wageningen, The Netherlands
| | - Vitor A. P. Martins Dos Santos
- Laboratory of Systems and Synthetic Biology, Wageningen University & Research, Wageningen, The Netherlands
- LifeGlimmer GmbH, Berlin, Germany
| | - Rene H. Wijffels
- Bioprocess Engineering and AlgaePARC, Wageningen University & Research, Wageningen, The Netherlands
- Nord University, Bodø, Norway
| | - Dirk E. Martens
- Bioprocess Engineering and AlgaePARC, Wageningen University & Research, Wageningen, The Netherlands
- * E-mail:
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Xue LL, Chen HH, Jiang JG. Implications of glycerol metabolism for lipid production. Prog Lipid Res 2017; 68:12-25. [PMID: 28778473 DOI: 10.1016/j.plipres.2017.07.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Revised: 07/06/2017] [Accepted: 07/31/2017] [Indexed: 12/13/2022]
Abstract
Triacylglycerol (TAG) is an important product in oil-producing organisms. Biosynthesis of TAG can be completed through either esterification of fatty acids to glycerol backbone, or through esterification of 2-monoacylglycerol. This review will focus on the former pathway in which two precursors, fatty acid and glycerol-3-phosphate (G3P), are required for TAG formation. Tremendous progress has been made about the enzymes or genes that regulate the biosynthetic pathway of TAG. However, much attention has been paid to the fatty acid provision and the esterification process, while the possible role of G3P is largely neglected. Glycerol is extensively studied on its usage as carbon source for value-added products, but the modification of glycerol metabolism, which is directly associated with G3P synthesis, is seldom recognized in lipid investigations. The relevance among glycerol metabolism, G3P synthesis and lipid production is described, and the role of G3P in glycerol metabolism and lipid production are discussed in detail with an emphasis on how G3P affects lipid production through the modulation of glycerol metabolism. Observations of lipid metabolic changes due to glycerol related disruption in mammals, plants, and microorganisms are introduced. Altering glycerol metabolism results in the changes of final lipid content. Possible regulatory mechanisms concerning the relationship between glycerol metabolism and lipid production are summarized.
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Affiliation(s)
- Lu-Lu Xue
- (a)College of Food and Bioengineering, South China University of Technology, Guangzhou 510640, China; (b)Industrial Crops Research Institute, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China
| | - Hao-Hong Chen
- (a)College of Food and Bioengineering, South China University of Technology, Guangzhou 510640, China
| | - Jian-Guo Jiang
- (a)College of Food and Bioengineering, South China University of Technology, Guangzhou 510640, China.
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Moses T, Mehrshahi P, Smith AG, Goossens A. Synthetic biology approaches for the production of plant metabolites in unicellular organisms. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:4057-4074. [PMID: 28449101 DOI: 10.1093/jxb/erx119] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Synthetic biology is the repurposing of biological systems for novel objectives and applications. Through the co-ordinated and balanced expression of genes, both native and those introduced from other organisms, resources within an industrial chassis can be siphoned for the commercial production of high-value commodities. This developing interdisciplinary field has the potential to revolutionize natural product discovery from higher plants, by providing a diverse array of tools, technologies, and strategies for exploring the large chemically complex space of plant natural products using unicellular organisms. In this review, we emphasize the key features that influence the generation of biorefineries and highlight technologies and strategic solutions that can be used to overcome engineering pitfalls with rational design. Also presented is a succinct guide to assist the selection of unicellular chassis most suited for the engineering and subsequent production of the desired natural product, in order to meet the global demand for plant natural products in a safe and sustainable manner.
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Affiliation(s)
- Tessa Moses
- Ghent University, Department of Plant Biotechnology and Bioinformatics, 9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052 Ghent, Belgium
| | - Payam Mehrshahi
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK
| | - Alison G Smith
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK
| | - Alain Goossens
- Ghent University, Department of Plant Biotechnology and Bioinformatics, 9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, 9052 Ghent, Belgium
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Schüler LM, Schulze PS, Pereira H, Barreira L, León R, Varela J. Trends and strategies to enhance triacylglycerols and high-value compounds in microalgae. ALGAL RES 2017. [DOI: 10.1016/j.algal.2017.05.025] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Yang H, Chen H, Hao G, Mei T, Zhang H, Chen W, Chen YQ. Increased fatty acid accumulation following overexpression of glycerol‐3‐phosphate dehydrogenase and suppression of β‐oxidation in oleaginous fungus
Mortierella alpina. EUR J LIPID SCI TECH 2016. [DOI: 10.1002/ejlt.201600113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Hua Yang
- State Key Laboratory of Food Science and TechnologySchool of Food Science and TechnologyJiangnan UniversityWuxiJiangsuP. R. China
| | - Haiqin Chen
- State Key Laboratory of Food Science and TechnologySchool of Food Science and TechnologyJiangnan UniversityWuxiJiangsuP. R. China
- Synergetic Innovation Center of Food Safety and NutritionWuxiJiangsuP. R. China
| | - Guangfei Hao
- State Key Laboratory of Food Science and TechnologySchool of Food Science and TechnologyJiangnan UniversityWuxiJiangsuP. R. China
- Synergetic Innovation Center of Food Safety and NutritionWuxiJiangsuP. R. China
| | - Tiantian Mei
- State Key Laboratory of Food Science and TechnologySchool of Food Science and TechnologyJiangnan UniversityWuxiJiangsuP. R. China
- Synergetic Innovation Center of Food Safety and NutritionWuxiJiangsuP. R. China
| | - Hao Zhang
- State Key Laboratory of Food Science and TechnologySchool of Food Science and TechnologyJiangnan UniversityWuxiJiangsuP. R. China
- Synergetic Innovation Center of Food Safety and NutritionWuxiJiangsuP. R. China
| | - Wei Chen
- State Key Laboratory of Food Science and TechnologySchool of Food Science and TechnologyJiangnan UniversityWuxiJiangsuP. R. China
- Synergetic Innovation Center of Food Safety and NutritionWuxiJiangsuP. R. China
| | - Yong Q. Chen
- State Key Laboratory of Food Science and TechnologySchool of Food Science and TechnologyJiangnan UniversityWuxiJiangsuP. R. China
- Synergetic Innovation Center of Food Safety and NutritionWuxiJiangsuP. R. China
- Department of Cancer BiologyWake Forest School of MedicineWinston‐SalemNCUSA
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Current advances in molecular, biochemical, and computational modeling analysis of microalgal triacylglycerol biosynthesis. Biotechnol Adv 2016; 34:1046-1063. [DOI: 10.1016/j.biotechadv.2016.06.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 06/08/2016] [Accepted: 06/12/2016] [Indexed: 12/12/2022]
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Yang B, Liu J, Jiang Y, Chen F. Chlorella species as hosts for genetic engineering and expression of heterologous proteins: Progress, challenge and perspective. Biotechnol J 2016; 11:1244-1261. [PMID: 27465356 DOI: 10.1002/biot.201500617] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 06/30/2016] [Accepted: 07/05/2016] [Indexed: 11/08/2022]
Abstract
The species of Chlorella represent a highly specialized group of green microalgae that can produce high levels of protein. Many Chlorella strains can grow rapidly and achieve high cell density under controlled conditions and are thus considered to be promising protein sources. Many advances in the genetic engineering of Chlorella have occurred in recent years, with significant developments in successful expression of heterologous proteins for various applications. Nevertheless, a lot of obstacles remain to be addressed, and a sophisticated and stable Chlorella expression system has yet to emerge. This review provides a brief summary of current knowledge on Chlorella and an overview of recent progress in the genetic engineering of Chlorella, and highlights the advances in the development of a genetic toolbox of Chlorella for heterologous protein expression. Research directions to further exploit the Chlorella expression system with respect to both challenges and perspectives are also discussed. This paper serves as a comprehensive literature review for the Chlorella community and will provide valuable insights into future exploration of Chlorella as a promising host for heterologous protein expression.
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Affiliation(s)
- Bo Yang
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, China.,School of Light Industry and Food Sciences, South China University of Technology, Guangzhou, China
| | - Jin Liu
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, China. .,Singapore-Peking University Research Centre for a Sustainable Low-Carbon Future, CREATE Tower, Singapore.
| | - Yue Jiang
- Runke Bioengineering Co., Ltd., Zhangzhou, China.
| | - Feng Chen
- Institute for Food and Bioresource Engineering, College of Engineering, Peking University, Beijing, China.,Singapore-Peking University Research Centre for a Sustainable Low-Carbon Future, CREATE Tower, Singapore
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Guihéneuf F, Khan A, Tran LSP. Genetic Engineering: A Promising Tool to Engender Physiological, Biochemical, and Molecular Stress Resilience in Green Microalgae. FRONTIERS IN PLANT SCIENCE 2016; 7:400. [PMID: 27066043 PMCID: PMC4815356 DOI: 10.3389/fpls.2016.00400] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 03/14/2016] [Indexed: 05/03/2023]
Abstract
As we march into the 21st century, the prevailing scenario of depleting energy resources, global warming and ever increasing issues of human health and food security will quadruple. In this context, genetic and metabolic engineering of green microalgae complete the quest toward a continuum of environmentally clean fuel and food production. Evolutionarily related, but unlike land plants, microalgae need nominal land or water, and are best described as unicellular autotrophs using light energy to fix atmospheric carbon dioxide (CO2) into algal biomass, mitigating fossil CO2 pollution in the process. Remarkably, a feature innate to most microalgae is synthesis and accumulation of lipids (60-65% of dry weight), carbohydrates and secondary metabolites like pigments and vitamins, especially when grown under abiotic stress conditions. Particularly fruitful, such an application of abiotic stress factors such as nitrogen starvation, salinity, heat shock, etc., can be used in a biorefinery concept for production of multiple valuable products. The focus of this mini-review underlies metabolic reorientation practices and tolerance mechanisms as applied to green microalgae under specific stress stimuli for a sustainable pollution-free future. Moreover, we entail current progress on genetic engineering as a promising tool to grasp adaptive processes for improving strains with potential biotechnological interests.
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Affiliation(s)
- Freddy Guihéneuf
- Botany and Plant Science, School of Natural Sciences, Ryan Institute, National University of Ireland GalwayGalway, Ireland
| | - Asif Khan
- Research Group Germline Biology, Centre for Organismal Studies (COS), Heidelberg UniversityHeidelberg, Germany
| | - Lam-Son P. Tran
- Plant Abiotic Stress Research Group & Faculty of Applied Sciences, Ton Duc Thang UniversityHo Chi Minh City, Vietnam
- Signaling Pathway Research Unit, RIKEN Center for Sustainable Resource ScienceTsurumi, Japan
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Ouyang LL, Li H, Yan XJ, Xu JL, Zhou ZG. Site-Directed Mutagenesis from Arg195 to His of a Microalgal Putatively Chloroplastidial Glycerol-3-Phosphate Acyltransferase Causes an Increase in Phospholipid Levels in Yeast. FRONTIERS IN PLANT SCIENCE 2016; 7:286. [PMID: 27014309 PMCID: PMC4785142 DOI: 10.3389/fpls.2016.00286] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Accepted: 02/22/2016] [Indexed: 06/05/2023]
Abstract
To analyze the contribution of glycerol-3-phosphate acyltransferase (GPAT) to the first acylation of glycerol-3-phosphate (G-3-P), the present study focused on a functional analysis of the GPAT gene from Lobosphaera incisa (designated as LiGPAT). A full-length cDNA of LiGPAT consisting of a 1,305-bp ORF, a 1,652-bp 5'-UTR, and a 354-bp 3'-UTR, was cloned. The ORF encoded a 434-amino acid peptide, of which 63 residues at the N-terminus defined a chloroplast transit peptide. Multiple sequence alignment and phylogeny analysis of GPAT homologs provided the convincible bioinformatics evidence that LiGPAT was localized to chloroplasts. Considering the conservation of His among the G-3-P binding sites from chloroplastidial GPATs and the substitution of His by Arg at position 195 in the LiGPAT mature protein (designated mLiGPAT), we established the heterologous expression of either mLiGPAT or its mutant (Arg195His) (sdmLiGPAT) in the GPAT-deficient yeast mutant gat1Δ. Lipid profile analyses of these transgenic yeasts not only validated the acylation function of LiGPAT but also indicated that the site-directed mutagenesis from Arg(195) to His led to an increase in the phospholipid level in yeast. Semi-quantitative analysis of mLiGPAT and sdmLiGPAT, together with the structural superimposition of their G-3-P binding sites, indicated that the increased enzymatic activity was caused by the enlarged accessible surface of the phosphate group binding pocket when Arg(195) was mutated to His. Thus, the potential of genetic manipulation of GPAT to increase the glycerolipid level in L. incisa and other microalgae would be of great interest.
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Affiliation(s)
- Long-Ling Ouyang
- College of Aqua-Life Science and Technology, Shanghai Ocean UniversityShanghai, China
| | - Hui Li
- Department of Biology and Food Engineering, Bengbu UniversityBengbu, China
| | - Xiao-Jun Yan
- Key Laboratory of Applied Marine Biotechnology, Ningbo UniversityNingbo, China
| | - Ji-Lin Xu
- Key Laboratory of Applied Marine Biotechnology, Ningbo UniversityNingbo, China
| | - Zhi-Gang Zhou
- College of Aqua-Life Science and Technology, Shanghai Ocean UniversityShanghai, China
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Misra N, Panda PK, Parida BK, Mishra BK. dEMBF: A Comprehensive Database of Enzymes of Microalgal Biofuel Feedstock. PLoS One 2016; 11:e0146158. [PMID: 26727469 PMCID: PMC4699747 DOI: 10.1371/journal.pone.0146158] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 12/14/2015] [Indexed: 12/22/2022] Open
Abstract
Microalgae have attracted wide attention as one of the most versatile renewable feedstocks for production of biofuel. To develop genetically engineered high lipid yielding algal strains, a thorough understanding of the lipid biosynthetic pathway and the underpinning enzymes is essential. In this work, we have systematically mined the genomes of fifteen diverse algal species belonging to Chlorophyta, Heterokontophyta, Rhodophyta, and Haptophyta, to identify and annotate the putative enzymes of lipid metabolic pathway. Consequently, we have also developed a database, dEMBF (Database of Enzymes of Microalgal Biofuel Feedstock), which catalogues the complete list of identified enzymes along with their computed annotation details including length, hydrophobicity, amino acid composition, subcellular location, gene ontology, KEGG pathway, orthologous group, Pfam domain, intron-exon organization, transmembrane topology, and secondary/tertiary structural data. Furthermore, to facilitate functional and evolutionary study of these enzymes, a collection of built-in applications for BLAST search, motif identification, sequence and phylogenetic analysis have been seamlessly integrated into the database. dEMBF is the first database that brings together all enzymes responsible for lipid synthesis from available algal genomes, and provides an integrative platform for enzyme inquiry and analysis. This database will be extremely useful for algal biofuel research. It can be accessed at http://bbprof.immt.res.in/embf.
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Affiliation(s)
- Namrata Misra
- Academy of Scientific and Innovative Research, CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, Odisha, India
- Bioresources Engineering Department, CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, Odisha, India
| | - Prasanna Kumar Panda
- Academy of Scientific and Innovative Research, CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, Odisha, India
- Bioresources Engineering Department, CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, Odisha, India
- * E-mail: ;
| | - Bikram Kumar Parida
- Bioresources Engineering Department, CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, Odisha, India
| | - Barada Kanta Mishra
- Academy of Scientific and Innovative Research, CSIR-Institute of Minerals and Materials Technology, Bhubaneswar, Odisha, India
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Gimpel JA, Henríquez V, Mayfield SP. In Metabolic Engineering of Eukaryotic Microalgae: Potential and Challenges Come with Great Diversity. Front Microbiol 2015; 6:1376. [PMID: 26696985 PMCID: PMC4678203 DOI: 10.3389/fmicb.2015.01376] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 11/20/2015] [Indexed: 12/03/2022] Open
Abstract
The great phylogenetic diversity of microalgae is corresponded by a wide arrange of interesting and useful metabolites. Nonetheless metabolic engineering in microalgae has been limited, since specific transformation tools must be developed for each species for either the nuclear or chloroplast genomes. Microalgae as production platforms for metabolites offer several advantages over plants and other microorganisms, like the ability of GMO containment and reduced costs in culture media, respectively. Currently, microalgae have proved particularly well suited for the commercial production of omega-3 fatty acids and carotenoids. Therefore most metabolic engineering strategies have been developed for these metabolites. Microalgal biofuels have also drawn great attention recently, resulting in efforts for improving the production of hydrogen and photosynthates, particularly triacylglycerides. Metabolic pathways of microalgae have also been manipulated in order to improve photosynthetic growth under specific conditions and for achieving trophic conversion. Although these pathways are not strictly related to secondary metabolites, the synthetic biology approaches could potentially be translated to this field and will also be discussed.
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Affiliation(s)
- Javier A Gimpel
- Chemical and Biotechnology Engineering Department, Centre for Biotechnology and Bioengineering, Universidad de Chile Santiago, Chile
| | - Vitalia Henríquez
- Instituto de Biología, Pontificia Universidad Católica de Valparaíso Valparaiso, Chile
| | - Stephen P Mayfield
- Division of Biological Sciences, California Center for Algae Biotechnology, University of California, San Diego La Jolla, CA, USA
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Bellou S, Baeshen MN, Elazzazy AM, Aggeli D, Sayegh F, Aggelis G. Microalgal lipids biochemistry and biotechnological perspectives. Biotechnol Adv 2014; 32:1476-93. [PMID: 25449285 DOI: 10.1016/j.biotechadv.2014.10.003] [Citation(s) in RCA: 177] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Revised: 10/02/2014] [Accepted: 10/06/2014] [Indexed: 01/05/2023]
Abstract
In the last few years, there has been an intense interest in using microalgal lipids in food, chemical and pharmaceutical industries and cosmetology, while a noteworthy research has been performed focusing on all aspects of microalgal lipid production. This includes basic research on the pathways of solar energy conversion and on lipid biosynthesis and catabolism, and applied research dealing with the various biological and technical bottlenecks of the lipid production process. In here, we review the current knowledge in microalgal lipids with respect to their metabolism and various biotechnological applications, and we discuss potential future perspectives. The committing step in fatty acid biosynthesis is the carboxylation of acetyl-CoA to form malonyl-CoA that is then introduced in the fatty acid synthesis cycle leading to the formation of palmitic and stearic acids. Oleic acid may also be synthesized after stearic acid desaturation while further conversions of the fatty acids (i.e. desaturations, elongations) occur after their esterification with structural lipids of both plastids and the endoplasmic reticulum. The aliphatic chains are also used as building blocks for structuring storage acylglycerols via the Kennedy pathway. Current research, aiming to enhance lipogenesis in the microalgal cell, is focusing on over-expressing key-enzymes involved in the earlier steps of the pathway of fatty acid synthesis. A complementary plan would be the repression of lipid catabolism by down-regulating acylglycerol hydrolysis and/or β-oxidation. The tendency of oleaginous microalgae to synthesize, apart from lipids, significant amounts of other energy-rich compounds such as sugars, in processes competitive to lipogenesis, deserves attention since the lipid yield may be considerably increased by blocking competitive metabolic pathways. The majority of microalgal production occurs in outdoor cultivation and for this reason biotechnological applications face some difficulties. Therefore, algal production systems need to be improved and harvesting systems need to be more effective in order for their industrial applications to become more competitive and economically viable. Besides, a reduction of the production cost of microalgal lipids can be achieved by combining lipid production with other commercial applications. The combined production of bioactive products and lipids, when possible, can support the commercial viability of both processes. Hydrophobic compounds can be extracted simultaneously with lipids and then purified, while hydrophilic compounds such as proteins and sugars may be extracted from the defatted biomass. The microalgae also have applications in environmental biotechnology since they can be used for bioremediation of wastewater and to monitor environmental toxicants. Algal biomass produced during wastewater treatment may be further valorized in the biofuel manufacture. It is anticipated that the high microalgal lipid potential will force research towards finding effective ways to manipulate biochemical pathways involved in lipid biosynthesis and towards cost effective algal cultivation and harvesting systems, as well.
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Affiliation(s)
- Stamatia Bellou
- Division of Genetics, Cell & Development Biology, Department of Biology, University of Patras, Patras 26504, Greece
| | - Mohammed N Baeshen
- Department of Biological Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Ahmed M Elazzazy
- Department of Biological Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia; Department of Chemistry of Natural and Microbial Products, National Research Centre, Dokki 12622, Giza, Egypt
| | - Dimitra Aggeli
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Fotoon Sayegh
- Department of Biological Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - George Aggelis
- Division of Genetics, Cell & Development Biology, Department of Biology, University of Patras, Patras 26504, Greece; Department of Biological Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
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Klok AJ, Lamers PP, Martens DE, Draaisma RB, Wijffels RH. Edible oils from microalgae: insights in TAG accumulation. Trends Biotechnol 2014; 32:521-8. [PMID: 25168414 DOI: 10.1016/j.tibtech.2014.07.004] [Citation(s) in RCA: 117] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 06/26/2014] [Accepted: 07/11/2014] [Indexed: 01/08/2023]
Abstract
Microalgae are a promising future source for sustainable edible oils. To make microalgal oil a cost-effective alternative for common vegetable oils, increasing TAG productivity and TAG content are of high importance. Fulfilling these targets requires proper understanding of lipid metabolism in microalgae. Here, we provide an overview of our current knowledge on the biology of TAG accumulation as well as the latest developments and future directions for increasing oil production in microalgae, considering both metabolic engineering techniques and cultivation strategies.
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Affiliation(s)
- A J Klok
- AlgaePARC, Bioprocess Engineering, Wageningen University, PO Box 8129, 6700 EV Wageningen, The Netherlands.
| | - P P Lamers
- AlgaePARC, Bioprocess Engineering, Wageningen University, PO Box 8129, 6700 EV Wageningen, The Netherlands
| | - D E Martens
- AlgaePARC, Bioprocess Engineering, Wageningen University, PO Box 8129, 6700 EV Wageningen, The Netherlands
| | - R B Draaisma
- Unilever Research and Development Vlaardingen, PO Box 114, 3133 AT Vlaardingen, The Netherlands
| | - R H Wijffels
- AlgaePARC, Bioprocess Engineering, Wageningen University, PO Box 8129, 6700 EV Wageningen, The Netherlands
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Janßen HJ, Steinbüchel A. Fatty acid synthesis in Escherichia coli and its applications towards the production of fatty acid based biofuels. BIOTECHNOLOGY FOR BIOFUELS 2014; 7:7. [PMID: 24405789 PMCID: PMC3896788 DOI: 10.1186/1754-6834-7-7] [Citation(s) in RCA: 180] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 12/24/2013] [Indexed: 05/04/2023]
Abstract
The idea of renewable and regenerative resources has inspired research for more than a hundred years. Ideally, the only spent energy will replenish itself, like plant material, sunlight, thermal energy or wind. Biodiesel or ethanol are examples, since their production relies mainly on plant material. However, it has become apparent that crop derived biofuels will not be sufficient to satisfy future energy demands. Thus, especially in the last decade a lot of research has focused on the production of next generation biofuels. A major subject of these investigations has been the microbial fatty acid biosynthesis with the aim to produce fatty acids or derivatives for substitution of diesel. As an industrially important organism and with the best studied microbial fatty acid biosynthesis, Escherichia coli has been chosen as producer in many of these studies and several reviews have been published in the fields of E. coli fatty acid biosynthesis or biofuels. However, most reviews discuss only one of these topics in detail, despite the fact, that a profound understanding of the involved enzymes and their regulation is necessary for efficient genetic engineering of the entire pathway. The first part of this review aims at summarizing the knowledge about fatty acid biosynthesis of E. coli and its regulation, and it provides the connection towards the production of fatty acids and related biofuels. The second part gives an overview about the achievements by genetic engineering of the fatty acid biosynthesis towards the production of next generation biofuels. Finally, the actual importance and potential of fatty acid-based biofuels will be discussed.
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Affiliation(s)
- Helge Jans Janßen
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 3, D-48149, Münster, Germany
| | - Alexander Steinbüchel
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 3, D-48149, Münster, Germany
- Environmental Sciences Department, King Abdulaziz University, Jeddah, Saudi Arabia
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Zavala-Moreno A, Arreguin-Espinosa R, Pardo JP, Romero-Aguilar L, Guerra-Sánchez G. Nitrogen Source Affects Glycolipid Production and Lipid Accumulation in the Phytopathogen Fungus <i>Ustilago maydis</i>. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/aim.2014.413104] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Misra N, Panda PK. In search of actionable targets for agrigenomics and microalgal biofuel production: sequence-structural diversity studies on algal and higher plants with a focus on GPAT protein. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2013; 17:173-86. [PMID: 23496307 DOI: 10.1089/omi.2012.0094] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The triacylglycerol (TAG) pathway provides several targets for genetic engineering to optimize microalgal lipid productivity. GPAT (glycerol-3-phosphate acyltransferase) is a crucial enzyme that catalyzes the initial step of TAG biosynthesis. Despite many recent biochemical studies, a comprehensive sequence-structure analysis of GPAT across diverse lipid-yielding organisms is lacking. Hence, we performed a comparative genomic analysis of plastid-located GPAT proteins from 7 microalgae and 3 higher plants species. The close evolutionary relationship observed between red algae/diatoms and green algae/plant lineages in the phylogenetic tree were further corroborated by motif and gene structure analysis. The predicted molecular weight, amino acid composition, Instability Index, and hydropathicity profile gave an overall representation of the biochemical features of GPAT protein across the species under study. Furthermore, homology models of GPAT from Chlamydomonas reinhardtii, Arabidopsis thaliana, and Glycine max provided deep insights into the protein architecture and substrate binding sites. Despite low sequence identity found between algal and plant GPATs, the developed models exhibited strikingly conserved topology consisting of 14α helices and 9β sheets arranged in two domains. However, subtle variations in amino acids of fatty acyl binding site were identified that might influence the substrate selectivity of GPAT. Together, the results will provide useful resources to understand the functional and evolutionary relationship of GPAT and potentially benefit in development of engineered enzyme for augmenting algal biofuel production.
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Affiliation(s)
- Namrata Misra
- Bioresources Engineering Department, CSIR-Institute of Minerals and Materials Technology, Bhubaneswar 751 013, Odisha, India
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