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Hao Y, Yu Y, Sun G, Gong X, Jiang Y, Lv G, Zhang Y, Li L, Zhao Y, Sun D, Gu W, Qian C. Effects of Multi-Walled Carbon Nanotubes and Nano-Silica on Root Development, Leaf Photosynthesis, Active Oxygen and Nitrogen Metabolism in Maize. PLANTS (BASEL, SWITZERLAND) 2023; 12:1604. [PMID: 37111828 PMCID: PMC10142641 DOI: 10.3390/plants12081604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 04/01/2023] [Accepted: 04/06/2023] [Indexed: 06/19/2023]
Abstract
Carbon nanotubes (MWCNTs) and nano-silica (nano-SiO2) are widely used in the field of life science because of their special physical and chemical properties. In this study, the effects of different concentrations of MWCNTs (0 mg·L-1, 200 mg·L-1, 400 mg·L-1, 800 mg·L-1 and 1200 mg·L-1) and nano-SiO2 (0 mg·L-1, 150 mg·L-1, 800 mg·L-1, 1500 mg·L-1 and 2500 mg·L-1) on maize seedling growth and relative mechanisms were explored. The main results are as follows: MWCNTs and nano-SiO2 can promote the growth of maize seedlings, and promote plant height, root length, the dry and fresh weight of seedlings, root-shoot ratio and so on. The ability to accumulate dry matter increased, the relative water content of leaves increased, the electrical conductivity of leaves decreased, the stability of cell membranes improved and the water metabolism ability of maize seedlings increased. The treatment of MWCNTs with 800 mg·L-1 and nano-SiO2 with 1500 mg·L-1 had the best effect on seedling growth. MWCNTs and nano-SiO2 can promote the development of root morphology, increase root length, root surface area, average diameter, root volume and total root tip number and improve root activity, so as to improve the absorption capacity of roots to water and nutrition. After MWCNT and nano-SiO2 treatment, compared with the control, the contents of O2·- and H2O2 decreased, and the damage of reactive oxygen free radicals to cells decreased. MWCNTs and nano-SiO2 can promote the clearance of reactive oxygen species and maintain the complete structure of cells, so as to slow down plant aging. The promoting effect of MWCNTs treated with 800 mg·L-1 and nano-SiO2 treated with 1500 mg·L-1 had the best effect. After treatment with MWCNTs and nano-SiO2, the activities of key photosynthesis enzymes PEPC, Rubisco, NADP-ME, NADP-MDH and PPDK of maize seedlings increased, which promoted the opening of stomata, improved the fixation efficiency of CO2, improved the photosynthetic process of maize plants and promoted plant growth. The promoting effect was the best when the concentration of MWCNTs was 800 mg·L-1 and the concentration of nano-SiO2 was 1500 mg·L-1. MWCNTs and nano-SiO2 can increase the activities of the enzymes GS, GOGAT, GAD and GDH related to nitrogen metabolism in maize leaves and roots, and can increase the content of pyruvate, so as to promote the synthesis of carbohydrates and the utilization of nitrogen and promote plant growth.
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Affiliation(s)
- Yubo Hao
- Institute of Crop Cultivation and Tillage, Heilongjiang Academy of Agricultural Sciences, Harbin 150028, China
| | - Yang Yu
- Institute of Crop Cultivation and Tillage, Heilongjiang Academy of Agricultural Sciences, Harbin 150028, China
| | - Guangyan Sun
- College of Agriculture, Northeast Agricultural University, Harbin 150030, China
| | - Xiujie Gong
- Institute of Crop Cultivation and Tillage, Heilongjiang Academy of Agricultural Sciences, Harbin 150028, China
| | - Yubo Jiang
- Institute of Crop Cultivation and Tillage, Heilongjiang Academy of Agricultural Sciences, Harbin 150028, China
| | - Guoyi Lv
- Institute of Crop Cultivation and Tillage, Heilongjiang Academy of Agricultural Sciences, Harbin 150028, China
| | - Yiteng Zhang
- Institute of Crop Cultivation and Tillage, Heilongjiang Academy of Agricultural Sciences, Harbin 150028, China
| | - Liang Li
- Institute of Crop Cultivation and Tillage, Heilongjiang Academy of Agricultural Sciences, Harbin 150028, China
| | - Yang Zhao
- Institute of Crop Cultivation and Tillage, Heilongjiang Academy of Agricultural Sciences, Harbin 150028, China
| | - Dan Sun
- Institute of Crop Resource, Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China
| | - Wanrong Gu
- College of Agriculture, Northeast Agricultural University, Harbin 150030, China
| | - Chunrong Qian
- Institute of Crop Cultivation and Tillage, Heilongjiang Academy of Agricultural Sciences, Harbin 150028, China
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Homologous and Heterologous Expression of Delta(12)-Desaturase in Mucor circinelloides Enhanced the Production of Linolenic Acid. Molecules 2022; 27:molecules27175511. [PMID: 36080278 PMCID: PMC9457725 DOI: 10.3390/molecules27175511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 08/22/2022] [Accepted: 08/24/2022] [Indexed: 11/21/2022] Open
Abstract
Linolenic acid (LA) is gaining more interest within the scientific community. This is because it has a potential medical role in reducing the risk of inflammation, carcinogenesis, atherosclerosis and diabetes and is a valuable nutraceutical for human health. The oleaginous fungus Mucor circinelloides produces a high lipid content (36%), including valuable polyunsaturated fatty acids (PUFAs). However, the critical step in which oleic acid (OA) is converted into LA is not efficient at supplying enough substrates for PUFA synthesis. Hence, we propose a method to increase LA production based on genetic engineering. The overexpression of the Δ12-desaturase gene from M. circinelloides and Mortierella alpina increased the LA content and improved the lipid accumulation (from 14.9% to 21.6% in the Δ12-desaturase gene of the M. circinelloides overexpressing strain (Mc-D12MC) and from 14.9% to 18.7% in the Δ12-desaturase gene of M. alpina overexpressing strain (Mc-D12MA)). Additionally, the up-regulated expression levels of these genes targeted the genes involved in NADPH production, implying that the elevated Δ12-desaturase gene may function as a critical regulator of NADPH and lipid synthesis in M. circinelloides. This study provides the first evidence to support the design of metabolic engineering related to LA and PUFA production in M. circinelloides for potential industrial applications.
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Fazili ABA, Shah AM, Albeshr MF, Naz T, Dar MA, Yang W, Garre V, Fazili KM, Bhat EA, Song Y. Overexpression of the Mitochondrial Malic Enzyme Genes (malC and malD) Improved the Lipid Accumulation in Mucor circinelloides WJ11. Front Microbiol 2022; 13:919364. [PMID: 35814694 PMCID: PMC9260706 DOI: 10.3389/fmicb.2022.919364] [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: 04/13/2022] [Accepted: 05/30/2022] [Indexed: 11/18/2022] Open
Abstract
Mucor circinelloides serves as a model organism to investigate the lipid metabolism in oleaginous microorganisms. It is considered as an important producer of γ-linolenic acid (GLA) that has vital medicinal benefits. In this study, we used WJ11, a high lipid-producing strain of M. circinelloides (36% w/w lipid, cell dry weight, CDW), to examine the role in lipid accumulation of two mitochondrial malic enzyme (ME) genes malC and malD. The homologous overexpression of both malC and malD genes enhanced the total lipid content of WJ11 by 41.16 and 32.34%, respectively. In parallel, the total content of GLA was enhanced by 16.73 and 46.76% in malC and malD overexpressing strains, respectively, because of the elevation of total lipid content. The fact that GLA content was enhanced more in the strain with lower lipid content increase and vice versa, indicated that engineering of mitochondrial MEs altered the fatty acid profile. Our results reveal that mitochondrial ME plays an important role in lipid metabolism and suggest that future approaches may involve simultaneous overexpression of distinct ME genes to boost lipid accumulation even further.
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Affiliation(s)
- Abu Bakr Ahmad Fazili
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Aabid Manzoor Shah
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | | | - Tahira Naz
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | | | - Wu Yang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Victoriano Garre
- Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, Murcia, Spain
| | | | - Eijaz Ahmed Bhat
- Centre de Biologie Structurale (CBS), Univ. Montpellier, CNRS, INSERM, Montpellier, France
| | - Yuanda Song
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
- *Correspondence: Yuanda Song,
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Response-Surface Statistical Optimization of Submerged Fermentation for Pectinase and Cellulase Production by Mucor circinelloides and M. hiemalis. FERMENTATION 2022. [DOI: 10.3390/fermentation8050205] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Cellulase and pectinase are degrading cellulosic and pectic substances that form plant cell walls and, thereby, they have a wide range of applications in the agro-industrial by-products recycling and food industries. In the current research, Mucor circinelloides and M. hiemalis strains were tested for their ability to produce cellulase and pectinase from tangerine peel by submerged fermentation. Experiments on five variables: temperature, pH, incubation period, inoculum size, and substrate concentration, were designed with a Box–Behnken design, as well as response surface methodology (RSM), and analysis of variance was performed. In addition, cellulase and pectinase were partially purified and characterized. At their optimum parameters, M. circinelloides and M. hiemalis afforded high cellulase production (37.20 U/mL and 33.82 U/mL, respectively) and pectinase (38.02 U/mL and 39.76 U/mL, respectively). The partial purification of M. circinelloides and M. hiemalis cellulase produced 1.73- and 2.03-fold purification with 31.12 and 32.02% recovery, respectively; meanwhile, 1.74- and 1.99-fold purification with 31.26 and 31.51% recovery, respectively, were obtained for pectinase. Partially purified cellulase and pectinase from M. circinelloides and M. hiemalis demonstrated the highest activity at neutral pH, and 70 and 50 °C, for cellulase and 50 and 60 °C, for pectinase, respectively. Moreover, 10 mM of K+ increased M. circinelloides enzymatic activity. The production of cellulase and pectinase from M. circinelloides and M. hiemalis utilizing RSM is deemed profitable for the decomposition of agro-industrial wastes.
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Fazili ABA, Shah AM, Zan X, Naz T, Nosheen S, Nazir Y, Ullah S, Zhang H, Song Y. Mucor circinelloides: a model organism for oleaginous fungi and its potential applications in bioactive lipid production. Microb Cell Fact 2022; 21:29. [PMID: 35227264 PMCID: PMC8883733 DOI: 10.1186/s12934-022-01758-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 02/10/2022] [Indexed: 11/10/2022] Open
Abstract
Microbial oils have gained massive attention because of their significant role in industrial applications. Currently plants and animals are the chief sources of medically and nutritionally important fatty acids. However, the ever-increasing global demand for polyunsaturated fatty acids (PUFAs) cannot be met by the existing sources. Therefore microbes, especially fungi, represent an important alternative source of microbial oils being investigated. Mucor circinelloides—an oleaginous filamentous fungus, came to the forefront because of its high efficiency in synthesizing and accumulating lipids, like γ-linolenic acid (GLA) in high quantity. Recently, mycelium of M. circinelloides has acquired substantial attraction towards it as it has been suggested as a convenient raw material source for the generation of biodiesel via lipid transformation. Although M. circinelloides accumulates lipids naturally, metabolic engineering is found to be important for substantial increase in their yields. Both modifications of existing pathways and re-formation of biosynthetic pathways in M. circinelloides have shown the potential to improve lipid levels. In this review, recent advances in various important metabolic aspects of M. circinelloides have been discussed. Furthermore, the potential applications of M. circinelloides in the fields of antioxidants, nutraceuticals, bioremediation, ethanol production, and carotenoids like beta carotene and astaxanthin having significant nutritional value are also deliberated.
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Wang X, Mohamed H, Bao Y, Wu C, Shi W, Song Y, Yang J. Heterologous Expression of Two Malate Transporters From an Oleaginous Fungus Mucor circinelloides Improved the Lipid Accumulation in Mucor lusitanicus. Front Microbiol 2021; 12:774825. [PMID: 34867915 PMCID: PMC8640210 DOI: 10.3389/fmicb.2021.774825] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 10/29/2021] [Indexed: 12/25/2022] Open
Abstract
The fungus, Mucor lusitanicus, is of great interest for microbial lipids, because of its ability to accumulate intracellular lipid using various carbon sources. The biosynthesis of fatty acid requires the reducing power NADPH, and acetyl-CoA, which is produced by the cleavage of citrate in cytosol. In this study, we employed different strategies to increase lipid accumulation in the low lipid-producing fungi via metabolic engineering technology. Hence, we constructed the engineered strain of M. lusitanicus CBS 277.49 by using malate transporter (mt) and 2-oxoglutarate: malate antiporter (sodit) from M. circinelloides WJ11. In comparison with the control strain, the lipid content of the overexpressed strains of mt and sodit genes were increased by 24.6 and 33.8%, respectively. These results showed that mt and sodit can affect the distribution of malate in mitochondria and cytosol, provide the substrates for the synthesis of citrate in the mitochondria, and accelerate the transfer of citrate from mitochondria to cytosol, which could play a significant regulatory role in fatty acid synthesis leading to lipids over accumulation.
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Affiliation(s)
- Xiuwen Wang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Hassan Mohamed
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China.,Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Assiut, Egypt
| | - Yonghong Bao
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Chen Wu
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Wenyue Shi
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Yuanda Song
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Junhuan Yang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
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Grujić M, Dojnov B, Potočnik I, Atanasova L, Duduk B, Srebotnik E, Druzhinina IS, Kubicek CP, Vujčić Z. Superior cellulolytic activity of Trichoderma guizhouense on raw wheat straw. World J Microbiol Biotechnol 2019; 35:194. [PMID: 31776792 DOI: 10.1007/s11274-019-2774-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 11/21/2019] [Indexed: 01/22/2023]
Abstract
Lignocellulosic plant biomass is the world's most abundant carbon source and has consequently attracted attention as a renewable resource for production of biofuels and commodity chemicals that could replace fossil resources. Due to its recalcitrant nature, it must be pretreated by chemical, physical or biological means prior to hydrolysis, introducing additional costs. In this paper, we tested the hypothesis that fungi which thrive on lignocellulosic material (straw, bark or soil) would be efficient in degrading untreated lignocellulose. Wheat straw was used as a model. We developed a fast and simple screening method for cellulase producers and tested one hundred Trichoderma strains isolated from wheat straw. The most potent strain-UB483FTG2/ TUCIM 4455, was isolated from substrate used for mushroom cultivation and was identified as T. guizhouense. After optimization of growth medium, high cellulase activity was already achieved after 72 h of fermentation on raw wheat straw, while the model cellulase overproducing strain T. reesei QM 9414 took 170 h and reached only 45% of the cellulase activity secreted by T. guizhouense. Maximum production levels were 1.1 U/mL (measured with CMC as cellulase substrate) and 0.7 U/mL (β-glucosidase assay). The T. guizhouense cellulase cocktail hydrolyzed raw wheat straw within 35 h. Our study shows that screening for fungi that successfully compete for special substrates in nature will lead to the isolation of strains with qualitatively and quantitatively superior enzymes needed for their digestion which could be used for industrial purposes.
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Affiliation(s)
- Marica Grujić
- Department of Biochemistry, Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia
| | - Biljana Dojnov
- Department of Chemistry, Institute of Chemistry, Technology and Metallurgy, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia.
| | - Ivana Potočnik
- Laboratory of Applied Phytopathology, Institute of Pesticides and Environmental Protection, Banatska 31b, PO Box 163, Belgrade, Serbia
| | - Lea Atanasova
- Microbiology and Applied Genomics Group, Research Division of Biochemical Technology, Institute of Chemical, Environmental and Bioscience Engineering (ICEBE), TU Wien, Gumpendorferstrasse 1a/E166-5, 1060, Vienna, Austria.,Institute of Food Technology, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190, Vienna, Austria
| | - Bojan Duduk
- Laboratory of Applied Phytopathology, Institute of Pesticides and Environmental Protection, Banatska 31b, PO Box 163, Belgrade, Serbia
| | - Ewald Srebotnik
- Bioresource Technology Group, Research Division of Bioresources and Plant Science, Institute of Chemical, Environmental and Bioscience Engineering (ICEBE), TU Wien, Getreidemarkt 9/E166-A, 1060, Vienna, Austria
| | - Irina S Druzhinina
- Microbiology and Applied Genomics Group, Research Division of Biochemical Technology, Institute of Chemical, Environmental and Bioscience Engineering (ICEBE), TU Wien, Gumpendorferstrasse 1a/E166-5, 1060, Vienna, Austria.,Jiangsu Provincial Key Lab of Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, China
| | - Christian P Kubicek
- Microbiology and Applied Genomics Group, Research Division of Biochemical Technology, Institute of Chemical, Environmental and Bioscience Engineering (ICEBE), TU Wien, Gumpendorferstrasse 1a/E166-5, 1060, Vienna, Austria.,, Steinschötelgasse 7, 1100, Vienna, Austria
| | - Zoran Vujčić
- Department of Biochemistry, Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia
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Rodrigues Reis CE, Bento HBS, Carvalho AKF, Rajendran A, Hu B, De Castro HF. Critical applications of Mucor circinelloides within a biorefinery context. Crit Rev Biotechnol 2019; 39:555-570. [PMID: 30931637 DOI: 10.1080/07388551.2019.1592104] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The establishment of an efficient and feasible biorefinery model depends on, among other factors, particularly the selection of the most appropriate microorganism. Mucor circinelloides is a dimorphic fungus species able to produce a wide variety of hydrolytic enzymes, lipids prone to biodiesel production, carotenoids, ethanol, and biomass with significant nutritional value. M. circinelloides also has been selected as a model species for genetic modification by being the first filamentous oleaginous species to have its genome fully characterized, as well as being a species characterized as a potential bioremediation agent. Considering the potential of replacing several nonrenewable feedstocks is widely dependent on fossil fuels, the exploitation of microbial processes and products is a desirable solution for promoting a green and sustainable future. Here, we introduce and thoroughly describe the recent and critical applications of this remarkable fungus within the context of developing a fungal-based biorefinery.
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Affiliation(s)
- Cristiano E Rodrigues Reis
- a Department of Chemical Engineering, Engineering School of Lorena , University of São Paulo , Lorena , São Paulo , Brazil
| | - Heitor B S Bento
- a Department of Chemical Engineering, Engineering School of Lorena , University of São Paulo , Lorena , São Paulo , Brazil
| | - Ana K F Carvalho
- a Department of Chemical Engineering, Engineering School of Lorena , University of São Paulo , Lorena , São Paulo , Brazil
| | - Aravindan Rajendran
- b Department of Bioproducts and Biosystems Engineering , University of Minnesota , Saint Paul , MN , USA
| | - Bo Hu
- b Department of Bioproducts and Biosystems Engineering , University of Minnesota , Saint Paul , MN , USA
| | - Heizir F De Castro
- a Department of Chemical Engineering, Engineering School of Lorena , University of São Paulo , Lorena , São Paulo , Brazil
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Chan LG, Cohen JL, Ozturk G, Hennebelle M, Taha AY, L. N. de Moura Bell JM. Bioconversion of cheese whey permeate into fungal oil by Mucor circinelloides. J Biol Eng 2018; 12:25. [PMID: 30473730 PMCID: PMC6237013 DOI: 10.1186/s13036-018-0116-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 10/11/2018] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Oleaginous fungi are efficient tools to convert agricultural waste streams into valuable components. The filamentous fungus Mucor circinelloides was cultivated in whey permeate, a byproduct from cheese production, to produce an oil-rich fungal biomass. Response surface methodology was used to optimize the fermentation conditions such as pH and temperature for increased biomass yield and lipid accumulation. Quantification and characterization of the fungal biomass oil was conducted. RESULTS Upstream lactose hydrolysis of the whey permeate increased the biomass yield from 2.4 to 7.8 (g dry biomass/L) compared to that of non-hydrolyzed whey permeate. The combination of low pH (4.5) and pasteurization minimized microbial competition, thus favoring fungal growth. A central composite rotatable design was used to evaluate the effects of temperature (22.4-33.6 °C) and a lower pH range (3.6-4.7) on biomass yield and composition. The highest biomass yield and oil content was observed at high temperature (33.6 °C), while the pH range evaluated had a less pronounced effect. The predictive model was validated at the optimal conditions of 33.6 °C and pH 4.5. The fungal biomass yield plateaued at 9 g dry cell weight per liter, while the oil content and lipid yield reached a maximum of 24% dry biomass and 2.20 g/L, respectively, at 168 h. Triacylglycerides were the major lipid class (92%), which contained predominantly oleic (41%), palmitic (23%), linoleic (11%), and γ-linolenic acid (9%). CONCLUSIONS This study provided an alternative way of valorization of cheese whey permeate by using it as a substrate for the production of value-added compounds by fungal fermentation. The fatty acid profile indicates the suitability of M. circinelloides oil as a potential feedstock for biofuel production and nutraceutical applications.
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Affiliation(s)
- Lauryn G. Chan
- Department of Food Science and Technology, University of California, Davis, One Shields Avenue, Davis, CA 95616 USA
| | - Joshua L. Cohen
- Department of Food Science and Technology, University of California, Davis, One Shields Avenue, Davis, CA 95616 USA
| | - Gulustan Ozturk
- Department of Food Science and Technology, University of California, Davis, One Shields Avenue, Davis, CA 95616 USA
| | - Marie Hennebelle
- Department of Food Science and Technology, University of California, Davis, One Shields Avenue, Davis, CA 95616 USA
| | - Ameer Y. Taha
- Department of Food Science and Technology, University of California, Davis, One Shields Avenue, Davis, CA 95616 USA
| | - Juliana Maria L. N. de Moura Bell
- Department of Food Science and Technology, University of California, Davis, One Shields Avenue, Davis, CA 95616 USA
- Department of Biological and Agricultural Engineering, Davis, One Shields Avenue, Davis, CA 95616 USA
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Li S, Li L, Xiong X, Ji X, Wei Y, Lin L, Zhang Q. A novel malic enzyme gene, Mime2, from Mortierella isabellina M6-22 contributes to lipid accumulation. Biotechnol Lett 2018; 40:1109-1118. [PMID: 29777513 DOI: 10.1007/s10529-018-2560-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 04/27/2018] [Indexed: 11/28/2022]
Abstract
OBJECTIVE This study was aimed at cloning and characterizing a novel malic enzyme (ME) gene of Mortierella isabellina M6-22 and identifying its relation with lipid accumulation. METHODS Mime2 was cloned from strain M6-22. Plasmid pET32aMIME2 was constructed to express ME of MIME2 in Escherichia coli BL21. After purification, the optimal pH and temperature of MIME2, as well as Km and Vmax for NADP+ were determined. The effects of EDTA or metal ions (Mn2+, Mg2+, Co2+, Cu2+, Ca2+, or Zn2+) on the enzymatic activity of MIME2 were evaluated. Besides, plasmid pRHMIME2 was created to express MIME2 in Rhodosporidium kratochvilovae YM25235, and its cell lipid content was measured by the acid-heating method. The optimal pH and temperature of MIME2 are 5.8 and 30 °C, respectively. RESULTS The act ivity of MIME2 was significantly increased by Mg2+, Ca2+, or Mn2+ at 0.5 mM but inhibited by Cu2+ or Zn2+ (p < 0.05). The optimal enzymatic activity of MIME2 is 177.46 U/mg, and the Km and Vmax for NADP+ are 0.703 mM and 156.25 μg/min, respectively. Besides, Mime2 transformation significantly increased the cell lipid content in strain YM25235 (3.15 ± 0.24 vs. 2.17 ± 0.31 g/L, p < 0.01). CONCLUSIONS The novel ME gene Mime2 isolated from strain M6-22 contributes to lipid accumulation in strain YM25235.
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Affiliation(s)
- Shan Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, 727 South Jingming Road, Kunming, 650500, Yunnan, China
| | - Lingyan Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, 727 South Jingming Road, Kunming, 650500, Yunnan, China
| | - Xiangfeng Xiong
- Faculty of Life Science and Technology, Kunming University of Science and Technology, 727 South Jingming Road, Kunming, 650500, Yunnan, China
| | - Xiuling Ji
- Faculty of Life Science and Technology, Kunming University of Science and Technology, 727 South Jingming Road, Kunming, 650500, Yunnan, China
| | - Yunlin Wei
- Faculty of Life Science and Technology, Kunming University of Science and Technology, 727 South Jingming Road, Kunming, 650500, Yunnan, China
| | - Lianbing Lin
- Faculty of Life Science and Technology, Kunming University of Science and Technology, 727 South Jingming Road, Kunming, 650500, Yunnan, China
| | - Qi Zhang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, 727 South Jingming Road, Kunming, 650500, Yunnan, China.
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Single Cell Oils (SCOs) of Oleaginous Filamentous Fungi as a Renewable Feedstock: A Biodiesel Biorefinery Approach. Fungal Biol 2018. [DOI: 10.1007/978-3-319-90379-8_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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12
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Tang X, Chen H, Gu Z, Zhang H, Chen YQ, Song Y, Chen W. Comparative Proteome Analysis between High Lipid-Producing Strain Mucor circinelloides WJ11 and Low Lipid-Producing Strain CBS 277.49. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:5074-5082. [PMID: 28557429 DOI: 10.1021/acs.jafc.7b00935] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Mucor circinelloides is one of few oleaginous fungi that produces a useful oil rich in γ-linolenic acid, but it usually only produces <25% total lipid. Nevertheless, we isolated a new strain WJ11 that can produce up to 36% lipid of cell dry weight. In this study, we have systematically analyzed the global changes in protein levels between the high lipid-producing strain WJ11 and the low lipid-producing strain CBS 277.49 (15%, lipid/cell dry weight) at lipid accumulation phase through comparative proteome analysis. Proteome analysis demonstrated that the branched-chain amino acid and lysine metabolism, glycolytic pathway, and pentose phosphate pathway in WJ11 were up-regulated, while the activities of tricarboxylic acid cycle and branch point enzyme for synthesis of isoprenoids were retarded compared with CBS 277.49. The coordinated regulation at proteome level indicate that more acetyl-CoA and NADPH are provided for fatty acid biosynthesis in WJ11 compared with CBS 277.49.
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Affiliation(s)
- Xin Tang
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University , Wuxi 214122, P.R. China
| | - Haiqin Chen
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University , Wuxi 214122, P.R. China
| | - Zhennan Gu
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University , Wuxi 214122, P.R. China
| | - Hao Zhang
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University , Wuxi 214122, P.R. China
| | - Yong Q Chen
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University , Wuxi 214122, P.R. China
| | - Yuanda Song
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University , Wuxi 214122, P.R. China
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology , Zibo 255100, P.R. China
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University , Wuxi 214122, P.R. China
- Beijing Innovation Center of Food Nutrition and Human Health, Beijing Technology and Business University , Beijing 100048, P.R. China
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13
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Tang X, Zan X, Zhao L, Chen H, Chen YQ, Chen W, Song Y, Ratledge C. Proteomics analysis of high lipid-producing strain Mucor circinelloides WJ11: an explanation for the mechanism of lipid accumulation at the proteomic level. Microb Cell Fact 2016; 15:35. [PMID: 26867592 PMCID: PMC4750200 DOI: 10.1186/s12934-016-0428-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 01/19/2016] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND The oleaginous fungus, Mucor circinelloides, is attracting considerable interest as it produces oil rich in γ-linolenic acid. Nitrogen (N) deficiency is a common strategy to trigger the lipid accumulation in oleaginous microorganisms. Although a simple pathway from N depletion in the medium to lipid accumulation has been elucidated at the enzymatic level, global changes at protein levels upon N depletion have not been investigated. In this study, we have systematically analyzed the changes at the levels of protein expression in M. circinelloides WJ11, a high lipid-producing strain (36 %, lipid/cell dry weight), during lipid accumulation. RESULTS Proteomic analysis demonstrated that N depletion increased the expression of glutamine synthetase, involved in ammonia assimilation, for the supply of cellular nitrogen but decreased the metabolism of amino acids. Upon N deficiency, many proteins (e.g., fructose-bisphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, enolase, pyruvate kinase) involved in glycolytic pathway were up-regulated while proteins involved in the tricarboxylic acid cycle (e.g., isocitrate dehydrogenase, succinyl-CoA ligase, succinate dehydrogenase, fumarate hydratase) were down-regulated, indicating this activity was retarded thereby leading to a greater flux of carbon into fatty acid biosynthesis. Moreover, glucose-6-phosphate dehydrogenase, transaldolase and transketolase, which participate in the pentose phosphate pathway, were up-regulated, leading to the increased production of NADPH, the reducing power for fatty acid biosynthesis. Furthermore, protein and nucleic acid metabolism were down-regulated and some proteins involved in energy metabolism, signal transduction, molecular chaperone and redox homeostasis were up-regulated upon N depletion, which may be the cellular response to the stress produced by the onset of N deficiency. CONCLUSION N limitation increased those expressions of the proteins involved in ammonia assimilation but decreased that involved in the biosynthesis of amino acids. Upon N deprivation, the glycolytic pathway was up-regulated, while the activity of the tricarboxylic acid cycle was retarded, thus, leading more carbon flux to fatty acid biosynthesis. Moreover, the pentose phosphate pathway was up-regulated, then this would increase the production of NADPH. Together, coordinated regulation of central carbon metabolism upon N limitation, provides more carbon flux to acetyl-CoA and NADPH for fatty acid biosynthesis.
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Affiliation(s)
- Xin Tang
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.
| | - Xinyi Zan
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.
| | - Lina Zhao
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.
| | - Haiqin Chen
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.
- Synergistic Innovation Center for Food Safety and Nutrition, Wuxi, People's Republic of China.
| | - Yong Q Chen
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.
- Synergistic Innovation Center for Food Safety and Nutrition, Wuxi, People's Republic of China.
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.
- Synergistic Innovation Center for Food Safety and Nutrition, Wuxi, People's Republic of China.
| | - Yuanda Song
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, People's Republic of China.
- Colin Ratledge Center for Microbial Lipids, School of Agriculture Engineering and Food Science, Shandong University of Technology, Zibo, People's Republic of China.
| | - Colin Ratledge
- Department of Biological Sciences, University of Hull, Hull, UK.
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14
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Liang YJ, Jiang JG. Characterization of malic enzyme and the regulation of its activity and metabolic engineering on lipid production. RSC Adv 2015. [DOI: 10.1039/c5ra04635a] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Nowadays, microbial lipids are employed as the feedstock for biodiesel production, which has attracted great attention across the whole world.
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Affiliation(s)
- Ying-Jie Liang
- School of Biological Science & Engineering
- South China University of Technology
- Guangzhou
- China
| | - Jian-Guo Jiang
- School of Biological Science & Engineering
- South China University of Technology
- Guangzhou
- China
- College of Food Science and Engineering
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15
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Yang J, Hu X, Zhang H, Chen H, Kargbo MR, Zhao J, Song Y, Chen YQ, Zhang H, Chen W. Expression, purification, and characterization of NADP+-dependent malic enzyme from the oleaginous fungus Mortierella alpina. Appl Biochem Biotechnol 2014; 173:1849-57. [PMID: 24861319 DOI: 10.1007/s12010-014-0971-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Accepted: 05/16/2014] [Indexed: 01/23/2023]
Abstract
Malic enzymes are a class of oxidative decarboxylases that catalyze the oxidative decarboxylation of malate to pyruvate and carbon dioxide, with concomitant reduction of NAD(P)+ to NAD(P)H. The NADP+-dependent malic enzyme in oleaginous fungi plays a key role in fatty acid biosynthesis. In this study, the malic enzyme-encoding complementary DNA (cDNA) (malE1) from the oleaginous fungus Mortierella alpina was cloned and expressed in Escherichia coli BL21 (DE3). The recombinant protein (MaME) was purified using Ni-NTA affinity chromatography. The purified enzyme used NADP+ as the cofactor. The K m values for L-malate and NADP+ were 2.19±0.01 and 0.38±0.02 mM, respectively, while the V max values were 147±2 and 302±14 U/mg, respectively, at the optimal condition of pH 7.5 and 33 °C. MaME is active in the presence of Mn2+, Mg2+, Co2+, Ni2+, and low concentrations of Zn2+ rather than Ca2+, Cu2+, or high concentrations of Zn2+. Oxaloacetic acid and glyoxylate inhibited the MaME activity by competing with malate, and their K i values were 0.08 and 0.6 mM, respectively.
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Affiliation(s)
- Jiayu Yang
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu Province, People's Republic of China
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16
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Ratledge C. The role of malic enzyme as the provider of NADPH in oleaginous microorganisms: a reappraisal and unsolved problems. Biotechnol Lett 2014; 36:1557-68. [PMID: 24752812 DOI: 10.1007/s10529-014-1532-3] [Citation(s) in RCA: 167] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 04/07/2014] [Indexed: 01/16/2023]
Abstract
Malic enzyme (ME; NADP(+)-dependent; EC 1.1.40) provides NADPH for lipid biosynthesis in oleaginous microorganisms. Its role in vivo depends on there being an adequate supply of NADH to drive malate dehydrogenase to convert oxaloacetate to malate as a component of a cycle of three reactions: pyruvate → oxaloacetate → malate and, by the action of ME, back to pyruvate. However, the availability of cytosolic NADH is limited and, consequently, ancillary means of producing NADPH are necessary. Stoichiometries are given for the conversion of glucose to triacylglycerols involving ME with and without the reactions of the pentose phosphate pathway (PPP) as an additional source of NADPH. Some oleaginous microorganisms (such as Yarrowia lipolytica), however, lack a cytosolic ME and, if the PPP is the sole provider of NADPH, the theoretical yield of triacylglycerol from glucose falls to 27.6 % (w/w) from 31.6 % when ME is present. An alternative route for NADPH generation via a cytosolic isocitrate dehydrogenase (NADP(+)-dependent) is then discussed.
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Affiliation(s)
- Colin Ratledge
- Department of Biological Sciences, University of Hull, Hull, HU6 7RX, UK,
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17
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Role of malic enzyme during fatty acid synthesis in the oleaginous fungus Mortierella alpina. Appl Environ Microbiol 2014; 80:2672-8. [PMID: 24532075 DOI: 10.1128/aem.00140-14] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The generation of NADPH by malic enzyme (ME) was postulated to be a rate-limiting step during fatty acid synthesis in oleaginous fungi, based primarily on the results from research focusing on ME in Mucor circinelloides. This hypothesis is challenged by a recent study showing that leucine metabolism, rather than ME, is critical for fatty acid synthesis in M. circinelloides. To clarify this, the gene encoding ME isoform E from Mortierella alpina was homologously expressed. ME overexpression increased the fatty acid content by 30% compared to that for a control. Our results suggest that ME may not be the sole rate-limiting enzyme, but does play a role, during fatty acid synthesis in oleaginous fungi.
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18
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Vorapreeda T, Thammarongtham C, Cheevadhanarak S, Laoteng K. Repertoire of malic enzymes in yeast and fungi: insight into their evolutionary functional and structural significance. Microbiology (Reading) 2013; 159:2548-2557. [DOI: 10.1099/mic.0.065342-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Affiliation(s)
- Tayvich Vorapreeda
- Biochemical Engineering and Pilot Plant Research and Development Unit, National Center for Genetic Engineering and Biotechnology. King Mongkut’s University of Technology Thonburi, Bangkhuntien, Bangkok 10150, Thailand
| | - Chinae Thammarongtham
- Biochemical Engineering and Pilot Plant Research and Development Unit, National Center for Genetic Engineering and Biotechnology. King Mongkut’s University of Technology Thonburi, Bangkhuntien, Bangkok 10150, Thailand
| | - Supapon Cheevadhanarak
- Pilot Plant Development and Training Institute, King Mongkut’s University of Technology Thonburi, Bangkhuntien, Bangkok 10150, Thailand
- School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi, Bangkhuntien, Bangkok 10150, Thailand
| | - Kobkul Laoteng
- Bioresources Technology Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Thailand Science Park, Pathum Thani 12120, Thailand
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19
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Vongsangnak W, Ruenwai R, Tang X, Hu X, Zhang H, Shen B, Song Y, Laoteng K. Genome-scale analysis of the metabolic networks of oleaginous Zygomycete fungi. Gene 2013; 521:180-90. [PMID: 23541380 DOI: 10.1016/j.gene.2013.03.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 03/07/2013] [Indexed: 10/27/2022]
Abstract
Microbial lipids are becoming an attractive option for the industrial production of foods and oleochemicals. To investigate the lipid physiology of the oleaginous microorganisms, at the system level, genome-scale metabolic networks of Mortierella alpina and Mucor circinelloides were constructed using bioinformatics and systems biology. As scaffolds for integrated data analysis focusing on lipid production, consensus metabolic routes governing fatty acid synthesis, and lipid storage and mobilisation were identified by comparative analysis of developed metabolic networks. Unique metabolic features were identified in individual fungi, particularly in NADPH metabolism and sterol biosynthesis, which might be related to differences in fungal lipid phenotypes. The frameworks detailing the metabolic relationship between M. alpina and M. circinelloides generated in this study is useful for further elucidation of the microbial oleaginicity, which might lead to the production improvement of microbial oils as alternative feedstocks for oleochemical industry.
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20
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Li Z, Sun H, Mo X, Li X, Xu B, Tian P. Overexpression of malic enzyme (ME) of Mucor circinelloides improved lipid accumulation in engineered Rhodotorula glutinis. Appl Microbiol Biotechnol 2012. [PMID: 23179623 DOI: 10.1007/s00253-012-4571-5] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The oleaginous yeast Rhodotorula glutinis has been known to be a potential feedstock for lipid production. In the present study, we investigated the enhancement of expression of malic enzyme (ME; NADP(+) dependent; EC 1.1.1.40) from Mucor circinelloides as a strategy to improve lipid content inside the yeast cells. The 26S rDNA and 5.8S rDNA gene fragments isolated from Rhodotorula glutinis were used for homologous integration of ME gene into R. glutinis chromosome under the control of the constitutively highly expressed gene phosphoglycerate kinase 1 to achieve stable expression. We demonstrated that by increasing the expression of the foreign ME gene in R. glutinis, we successfully improved the lipid content by more than twofold. At the end of lipid accumulation phrase (96 h) in the transformants, activity of ME was increased by twofold and lipid content of the yeast cells was increased from 18.74 % of the biomass to 39.35 %. Simultaneously, there were no significant differences in fatty acid profiles between the wild-type strain and the recombinant strain. Over 94 % of total fatty acids were C16:0, C18:0, C16:1, C18:1, and C18:2. Our results indicated that heterologous expression of NADP(+)-dependent ME involved in fatty acid biosynthesis indeed increased the lipid accumulation in the oleaginous yeast R. glutinis.
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Affiliation(s)
- Zhi Li
- Institute of Genomic Medicine, College of Pharmacy, Jinan University, Guangzhou 510632, China
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21
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Rodríguez-Frómeta RA, Gutiérrez A, Torres-Martínez S, Garre V. Malic enzyme activity is not the only bottleneck for lipid accumulation in the oleaginous fungus Mucor circinelloides. Appl Microbiol Biotechnol 2012; 97:3063-72. [PMID: 23053085 DOI: 10.1007/s00253-012-4432-2] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 09/07/2012] [Accepted: 09/10/2012] [Indexed: 10/27/2022]
Abstract
Commercial interest in microbial lipids is increasing due to their potential use as feedstock for biodiesel production. The supply of NADPH generated by malic enzyme (ME; NADP+-dependent; EC 1.1.1.40) has been postulated as being the rate-limiting step for fatty acid biosynthesis in oleaginous fungi, based mainly on data from the zygomycete Mucor circinelloides studies. This fungus contains five genes that code for six different ME isoforms. One of these genes, malA, codes for the isoforms III and IV, which have previously been associated with lipid accumulation. Following a strategy of targeted integration of an engineered malA gene, a stable strain overexpressing malA and showing high ME activity has been obtained, demonstrating the feasibility of this strategy to overexpress genes of biotechnological interest in M. circinelloides. This is the first report showing the integration and overexpression of a gene in Zygomycetes. Unexpectedly, the genetically modified strain showed a lipid content similar to that of a prototrophic non-overexpressing control strain, suggesting that another limiting step in the fatty acid synthesis pathway may have been revealed as a consequence of the elimination of malic enzyme-based bottleneck. Otherwise, the fact that prototrophic strains showed at least a 2.5-fold increase in lipid accumulation in comparison with leucine auxotrophic strains suggests that a wild-type leucine biosynthetic pathway is required for lipid accumulation. Moreover, increasing concentrations of leucine in culture medium increased growth of auxotrophs but failed to increase lipid content, suggesting that the leucine synthesized by the fungus is the only leucine available for lipid biosynthesis. These results support previous data postulating leucine metabolism as one of the pathways involved in the generation of the acetyl-CoA required for fatty acid biosynthesis.
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Affiliation(s)
- Rosa Amarilis Rodríguez-Frómeta
- Departamento de Genética y Microbiología (Unidad asociada al IQFR-CSIC), Facultad de Biología, Universidad de Murcia, 30071, Murcia, Spain.
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22
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Vongsangnak W, Zhang Y, Chen W, Ratledge C, Song Y. Annotation and analysis of malic enzyme genes encoding for multiple isoforms in the fungus Mucor circinelloides CBS 277.49. Biotechnol Lett 2012; 34:941-7. [PMID: 22367279 DOI: 10.1007/s10529-012-0859-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2011] [Accepted: 01/17/2012] [Indexed: 10/14/2022]
Abstract
Based on the newly-released genomic data of Mucor circinelloides CBS 277.49, we have annotated five genes encoding for malic enzyme: all code for proteins that contain conserved domains/motifs for malic acid binding, NAD(+) binding and NAD(P)(+) binding. Phylogenetic analysis for malic enzyme genes showed that genes ID 78524 and 11639 share ~80% amino acid identity and are grouped in cluster 1; genes ID 182779, 186772 and 116127 share ~66% amino acid identity are grouped in cluster 2. Genes ID 78524, 11639 and 166127 produce proteins that are localized in the mitochondrion, while the products from genes 182779 and 186772 are localized in the cytosol. Based on the comparative analysis published previously by Song et al. (Microbiology 147:1507-1515, 2001), we propose that malic enzyme genes ID 78524, 166127, 182779, 186772, 11639, respectively, represent protein isoforms I, II, III/IV, V, and VI.
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Affiliation(s)
- Wanwipa Vongsangnak
- Center for Systems Biology, Soochow University, Suzhou, 215006, People's Republic of China.
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23
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Biochemical properties and physiological roles of NADP-dependent malic enzyme in Escherichia coli. J Microbiol 2011; 49:797-802. [PMID: 22068497 DOI: 10.1007/s12275-011-0487-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Accepted: 04/25/2011] [Indexed: 10/15/2022]
Abstract
Malic enzymes catalyze the reversible oxidative decarboxylation of L-malate using NAD(P)(+) as a cofactor. NADP-dependent malic enzyme (MaeB) from Escherichia coli MG1655 was expressed and purified as a fusion protein. The molecular weight of MaeB was about 83 kDa, as determined by SDS-PAGE. The recombinant MaeB showed a maximum activity at pH 7.8 and 46°C. MaeB activity was dependent on the presence of Mn(2+) but was strongly inhibited by Zn(2+). In order to understand the physiological roles, recombinant E. coli strains (icd (NADP)/ΔmaeB and icd (NAD)/ΔmaeB) containing NADP-dependent isocitrate dehydrogenase (IDH), or engineered NAD-dependent IDH with the deletion of the maeB gene, were constructed using homologous recombination. During growth on acetate, icd (NAD)/ΔmaeB grew poorly, having a growth rate only 60% that of the wild-type strain (icd (NADP)). Furthermore, icd (NADP)/ΔmaeB exhibited a 2-fold greater adaptability to acetate than icd (NAD)/ΔmaeB, which may be explained by more NADPH production for biosynthesis in icd (NADP)/ΔmaeB due to its NADP-dependent IDH. These results indicated that MaeB was important for NADPH production for bacterial growth on acetate. We also observed that MaeB activity was significantly enhanced (7.83-fold) in icd (NAD), which was about 3-fold higher than that in icd (NADP), when switching from glucose to acetate. The marked increase of MaeB activity was probably induced by the shortage of NADPH in icd (NAD). Evidently, MaeB contributed to the NADPH generation needed for bacterial growth on two carbon compounds.
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Vorapreeda T, Thammarongtham C, Cheevadhanarak S, Laoteng K. Alternative routes of acetyl-CoA synthesis identified by comparative genomic analysis: involvement in the lipid production of oleaginous yeast and fungi. MICROBIOLOGY-SGM 2011; 158:217-228. [PMID: 22016567 DOI: 10.1099/mic.0.051946-0] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
For a bio-based economy, microbial lipids offer a potential solution as alternative feedstocks in the oleochemical industry. The existing genome data for the promising strains, oleaginous yeasts and fungi, allowed us to investigate candidate orthologous sequences that participate in their oleaginicity. Comparative genome analysis of the non-oleaginous (Saccharomyces cerevisiae, Candida albicans and Ashbya gossypii) and oleaginous strains (Yarrowia lipolytica, Rhizopus oryzae, Aspergillus oryzae and Mucor circinelloides) showed that 209 orthologous protein sequences of the oleaginous microbes were distributed over several processes of the cells. Based on the 41 sequences categorized by metabolism, putative routes potentially involved in the generation of precursors for fatty acid and lipid synthesis, particularly acetyl-CoA, were then identified that were not present in the non-oleaginous strains. We found a set of the orthologous oleaginous proteins that was responsible for the biosynthesis of this key two-carbon metabolite through citrate catabolism, fatty acid β-oxidation, leucine metabolism and lysine degradation. Our findings suggest a relationship between carbohydrate, lipid and amino acid metabolism in the biosynthesis of acetyl-CoA, which contributes to the lipid production of oleaginous microbes.
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Affiliation(s)
- Tayvich Vorapreeda
- Biochemical Engineering and Pilot Plant Research and Development Unit, National Center for Genetic Engineering and Biotechnology at King Mongkut's University of Technology Thonburi, Bangkhuntien, Bangkok 10150, Thailand
| | - Chinae Thammarongtham
- Biochemical Engineering and Pilot Plant Research and Development Unit, National Center for Genetic Engineering and Biotechnology at King Mongkut's University of Technology Thonburi, Bangkhuntien, Bangkok 10150, Thailand
| | - Supapon Cheevadhanarak
- Pilot Plant Development and Training Institute, King Mongkut's University of Technology Thonburi, Bangkhuntien, Bangkok 10150, Thailand.,School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkhuntien, Bangkok 10150, Thailand
| | - Kobkul Laoteng
- Biochemical Engineering and Pilot Plant Research and Development Unit, National Center for Genetic Engineering and Biotechnology at King Mongkut's University of Technology Thonburi, Bangkhuntien, Bangkok 10150, Thailand
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25
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Meeuwse P, Tramper J, Rinzema A. Modeling lipid accumulation in oleaginous fungi in chemostat cultures: I. Development and validation of a chemostat model for Umbelopsis isabellina. Bioprocess Biosyst Eng 2011; 34:939-49. [PMID: 21538015 PMCID: PMC3171664 DOI: 10.1007/s00449-011-0545-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Accepted: 04/05/2011] [Indexed: 11/24/2022]
Abstract
Lipid-accumulating fungi may be able to produce biodiesel precursors from agricultural wastes. As a first step in understanding and evaluating their potential, a mathematical model was developed to describe growth, lipid accumulation and substrate consumption of the oleaginous fungus Umbelopsis isabellina (also known as Mortierella isabellina) in submerged chemostat cultures. Key points of the model are: (1) if the C-source supply rate is limited, maintenance has a higher priority than growth, which has a higher priority than lipid production; (2) the maximum specific lipid production rate of the fungus is independent of the actual specific growth rate. Model parameters were obtained from chemostat cultures of U. isabellina grown on mineral media with glucose and NH(4) (+). The model describes the results of chemostat cultures well for D > 0.04 h(-1), but it has not been validated for lower dilution rates because of practical problems with the filamentous fungus. Further validation using literature data for oleaginous yeasts is described in part II of this paper. Our model shows that not only the C/N-ratio of the feed, but also the dilution rate highly influences the lipid yield in chemostat cultures.
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Affiliation(s)
- Petra Meeuwse
- Bioprocess Engineering, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands
| | - Johannes Tramper
- Bioprocess Engineering, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands
| | - Arjen Rinzema
- Bioprocess Engineering, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands
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26
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Meeuwse P, Tramper J, Rinzema A. Modeling lipid accumulation in oleaginous fungi in chemostat cultures. II: Validation of the chemostat model using yeast culture data from literature. Bioprocess Biosyst Eng 2011; 34:951-61. [PMID: 21516366 PMCID: PMC3171657 DOI: 10.1007/s00449-011-0546-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Accepted: 04/05/2011] [Indexed: 11/30/2022]
Abstract
A model that predicts cell growth, lipid accumulation and substrate consumption of oleaginous fungi in chemostat cultures (Meeuwse et al. in Bioproc Biosyst Eng. doi:10.1007/s00449-011-0545-8, 2011) was validated using 12 published data sets for chemostat cultures of oleaginous yeasts and one published data set for a poly-hydroxyalkanoate accumulating bacterial species. The model could describe all data sets well with only minor modifications that do not affect the key assumptions, i.e. (1) oleaginous yeasts and fungi give the highest priority to C-source utilization for maintenance, second priority to growth and third priority to lipid accumulation, and (2) oleaginous yeasts and fungi have a growth rate independent maximum specific lipid production rate. The analysis of all data showed that the maximum specific lipid production rate is in most cases very close to the specific production rate of membrane and other functional lipids for cells growing at their maximum specific growth rate. The limiting factor suggested by Ykema et al. (in Biotechnol Bioeng 34:1268–1276, 1989), i.e. the maximum glucose uptake rate, did not give good predictions of the maximum lipid production rate.
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Affiliation(s)
- Petra Meeuwse
- Bioprocess Engineering, Wageningen University, PO Box 8129, 6700 EV Wageningen, The Netherlands
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Multiple isoforms of malic enzyme in the oleaginous fungus, Mortierella alpina. ACTA ACUST UNITED AC 2008; 112:725-30. [DOI: 10.1016/j.mycres.2008.01.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Revised: 12/17/2007] [Accepted: 01/10/2008] [Indexed: 11/21/2022]
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Zhang Y, Adams IP, Ratledge C. Malic enzyme: the controlling activity for lipid production? Overexpression of malic enzyme in Mucor circinelloides leads to a 2.5-fold increase in lipid accumulation. MICROBIOLOGY-SGM 2007; 153:2013-2025. [PMID: 17600047 DOI: 10.1099/mic.0.2006/002683-0] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Malic enzyme (ME; NADP(+)-dependent; EC 1 . 1 . 1 . 40) has been postulated to be the rate-limiting step for fatty acid biosynthesis in oleaginous fungi in which the extent of lipid accumulation is below the maximum possible. The genes encoding the isoform of ME involved in fatty acid synthesis were identified in Mucor circinelloides and Mortierella alpina, two commercially useful oil-producing fungi, using degenerate primers. Both showed high similarity with ME genes from other micro-organisms. The whole-length ME gene from each source was cloned into a leucine auxotroph of Mc. circinelloides and placed under the control of the constitutive glyceraldehyde-3-phosphate dehydrogenase gene (gpd1) promoter. After confirming correct expression of the ME genes, the two recombinant strains were grown in fully controlled, submerged-culture bioreactors using a high C : N ratio medium for lipid accumulation. Activities of ME were increased by two- to threefold and the lipid contents of the cells, in both recombinants, were increased from 12 % of the biomass to 30 %. Simultaneously, the degree of fatty acid desaturation increased slightly. Thus, increased expression of the ME gene leads to both increased biosynthesis of fatty acids and formation of unsaturated fatty acids, including gamma-linolenic acid (18 : 3 n-6). At the end of lipid accumulation (96 h), ME activity in the recombinant strains had ceased, as it had done in the parent wild-type cells, indicating that additional, but unknown, controls over its activity must be in place to account for this loss of activity: this may be due to the presence of a specific ME-cleaving enzyme. The hypothesis that the rate-limiting step of fatty acid biosynthesis is therefore the supply of NADPH, as generated specifically and solely by ME, is therefore considerably strengthened by these results.
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Affiliation(s)
- Ying Zhang
- Department of Biological Sciences, University of Hull, Hull HU6 7RX, UK
| | - Ian P Adams
- Department of Biological Sciences, University of Hull, Hull HU6 7RX, UK
| | - Colin Ratledge
- Department of Biological Sciences, University of Hull, Hull HU6 7RX, UK
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Li Y, Adams IP, Wynn JP, Ratledge C. Cloning and characterization of a gene encoding a malic enzyme involved in anaerobic growth in Mucor circinelloides. ACTA ACUST UNITED AC 2005; 109:461-8. [PMID: 15912934 DOI: 10.1017/s0953756205002480] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A 3193 bp contiguous sequence has been cloned from the oleaginous fungus Mucor circinelloides, that contains a full-length gene encoding a putative NADP+: dependent malic enzyme (EC. 1.1.1.40). The cloned DNA contains a 2154 bp putative open reading frame containing five introns and encoding a protein of 616 amino acids. The gene encoded what appeared to be an anaerobic isoform of malic enzyme (isoform II); this conclusion is supported by transcript analysis and by the fact that the ORF contains an N-terminal mitochondrial target sequence (a similar cellular location was identified for the anaerobic malic enzyme in Saccharomyces cerevisiae; Boles et al. 1998). The cloned gene did not encode either isoform III (the isoform associated with active growth) or isoform IV (associated with lipid accumulation) previously identified. M. circinelloides therefore must possess (at least) two structural genes for malic enzyme.
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Affiliation(s)
- Yonghua Li
- Centre for Lipid Research, University of Hull, Cottingham Road, Hull HU6 7RX, UK
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Volschenk H, van Vuuren HJJ, Viljoen-Bloom M. Malo-ethanolic fermentation in Saccharomyces and Schizosaccharomyces. Curr Genet 2003; 43:379-91. [PMID: 12802505 DOI: 10.1007/s00294-003-0411-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2003] [Revised: 05/12/2003] [Accepted: 05/13/2003] [Indexed: 11/28/2022]
Abstract
Yeast species are divided into the K(+) or K(-) groups, based on their ability or inability to metabolise tricarboxylic acid (TCA) cycle intermediates as sole carbon or energy source. The K(-) group of yeasts includes strains of Saccharomyces, Schizosaccharomyces pombe and Zygosaccharomyces bailii, which is capable of utilising TCA cycle intermediates only in the presence of glucose or other assimilable carbon sources. Although grouped together, these yeasts have significant differences in their abilities to degrade malic acid. Typically, strains of Saccharomyces are regarded as inefficient metabolisers of extracellular malic acid, whereas strains of Sch. pombe and Z. bailii can effectively degrade high concentrations of malic acid. The ability of a yeast strain to degrade extracellular malic acid is dependent on both the efficient transport of the dicarboxylic acid and the efficacy of the intracellular malic enzyme. The malic enzyme converts malic acid into pyruvic acid, which is further metabolised to ethanol and carbon dioxide under fermentative conditions via the so-called malo-ethanolic (ME) pathway. This review focuses on the enzymes involved in the ME pathway in Sch. pombe and Saccharomyces species, with specific emphasis on the malate transporter and the intracellular malic enzyme.
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Affiliation(s)
- H Volschenk
- Department of Microbiology, Stellenbosch University, Private Bag X1, 7602 Matieland, South Africa
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Ratledge C, Wynn JP. The biochemistry and molecular biology of lipid accumulation in oleaginous microorganisms. ADVANCES IN APPLIED MICROBIOLOGY 2003; 51:1-51. [PMID: 12236054 DOI: 10.1016/s0065-2164(02)51000-5] [Citation(s) in RCA: 531] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Colin Ratledge
- Lipid Research Centre, Department of Biological Sciences, University of Hull, HU6 7RX, United Kingdom
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