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Zhang Y, Yang Y, Liu Q, Li S, Song Y. Lipid Accumulation by Snf-β Engineered Mucor circinelloides Strains on Glucose and Xylose. Appl Biochem Biotechnol 2023; 195:7697-7707. [PMID: 37086376 DOI: 10.1007/s12010-023-04531-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2023] [Indexed: 04/23/2023]
Abstract
Sucrose non-fermenting 1 (SNF1) protein kinase plays the regulatory roles in the utilization of selective carbon sources and lipid metabolism. Previously, the role of β subunit of SNF1 in lipid accumulation was evaluated by overexpression and knockout of Snf-β in oleaginous fungus M. circinelloides. In the present study, the growth and lipid accumulation of Snf-β overexpression and knockout strains were further analyzed and compared with glucose or xylose as a single or mixed carbon sources. The results showed that the lipid contents in Snf-β knockout strain improved by 23.2% (for glucose), 28.4% (for xylose), and 30.5% (for mixed glucose and xylose) compared with that of the control strain, respectively. The deletion of Snf-β subunit also altered the transcriptional level of acetyl-CoA carboxylase (ACC). The highest transcriptional levels of ACC1 in Snf-β knockout strain at 24 h were increased by 2.4-fold (for glucose), 2.8-fold (for xylose), and 3.1-fold (for mixed glucose and xylose) compared with that of the control strain, respectively. Our results indicated that Snf-β subunit enhanced lipid accumulation through the regulation of ACC1 in response to xylose or mixed sugars of glucose and xylose more significantly than that of response to glucose. This is the first study to explore the effect of Snf-β subunit of M. circinelloides in regulating lipid accumulation responding to different carbon nutrient signals of glucose and xylose. This study provides a foundation for the future application of the Snf-β engineered strains in lipid production from lignocellulose.
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Affiliation(s)
- Yao Zhang
- Food Bioengineering and Technology Laboratory, Department of Food Science and Nutrition, College of Culture and Tourism, University of Jinan, 13 Shungeng Road, Jinan, 250022, People's Republic of China.
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China.
| | - Yueping Yang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China
| | - Qing Liu
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China
| | - Shaoqi Li
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China
| | - Yuanda Song
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China
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2
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Zhang Y, Yang Y, Zhang S, Liu Q, Dang W, Song Y. Lipid accumulation and SNF1 transcriptional analysis of Mucor circinelloides on xylose under nitrogen limitation. Antonie Van Leeuwenhoek 2023; 116:383-391. [PMID: 36656419 DOI: 10.1007/s10482-023-01810-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Accepted: 01/12/2023] [Indexed: 01/20/2023]
Abstract
Sucrose non-fermenting 1 (SNF1) plays a crucial role in utilizing non-glucose carbon sources and regulating lipid metabolism. However, the mechanism by which SNF1 regulates lipid accumulation in oleaginous filamentous fungi in response to nutrient signals remains unclear. In the present study, by analysing the growth and lipid accumulation of M. circinelloides on xylose under nitrogen limitation, combined with the transcriptional changes of each subunit of SNF1, the regulation of SNF1 between nutrient signal and lipid accumulation was explored. The results showed that with the increase of carbon/nitrogen (C/N) ratio, the xylose consumption and cell growth of M. circinelloides decreased, and the lipid accumulation increased gradually. The optimal C/N ratio was 160:1, and the maximum lipid yield was 4.1 g/L. Two subunits of SNF1, Snf-α1 and Snf-β, are related to the regulation of lipid metabolism in response to nutrient signals from different external nitrogen sources. This is the first report on the transcriptional analysis of SNF1 subunits on xylose metabolism under nitrogen limitation. This study provides a basis for further understanding of lipid synthesis mechanism on xylose in oleaginous fungi, and it also lays a foundation for the genetic engineering of high-lipid strain.
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Affiliation(s)
- Yao Zhang
- Food Bioengineering and Technology Laboratory, Department of Food Science and Nutrition, College of Culture and Tourism, University of Jinan, 13 Shungeng Road, Jinan, 250022, People's Republic of China.
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China.
| | - Yueping Yang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China
| | - Silu Zhang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China
| | - Qing Liu
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China
| | - Wenrui Dang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China
| | - Yuanda Song
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000, People's Republic of China
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Zhang Y, Yang Y, Zhang H, Liu Q, Song Y. Effect of Different Carbons on Lipid Production and SNF1 Transcription in Mucor Circinelloides. Indian J Microbiol 2023; 63:146-151. [PMID: 37188240 PMCID: PMC10172402 DOI: 10.1007/s12088-023-01070-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 02/20/2023] [Indexed: 03/06/2023] Open
Abstract
Sucrose non-fermenting 1 (SNF1) protein kinase plays an important role in the utilization of selective carbon sources and regulation of lipid metabolism. In order to further explore the function of SNF1 in regulating lipid accumulation by responding nutritional signals from non-glucose carbon sources, in the present study, the lipid production and SNF1 transcriptional levels of Mucor circinelloides were analyzed and compared on different carbon sources. The results indicated that M. circinelloides could effectively utilize some secondary metabolic carbon sources of monosaccharides and disaccharides for growth and lipids production, such as fructose, maltose and galactose. Snf-β subunit was associated with the regulation of lipid metabolism in response to nutritional signals from different carbon sources. This is the first report on the transcriptional analysis of SNF1 subunits on different carbons metabolism in oleaginous filamentous fungi. This research has suggested that genetic engineering of SNF1 subunits will alter the lipid production of M. circinelloides from alternative carbon sources. Supplementary Information The online version contains supplementary material available at 10.1007/s12088-023-01070-z.
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Affiliation(s)
- Yao Zhang
- Food Bioengineering and Technology Laboratory, Department of Food Science and Nutrition, College of Culture and Tourism, University of Jinan, 13 Shungeng Road, Jinan, 250022 People’s Republic of China
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000 People’s Republic of China
| | - Yueping Yang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000 People’s Republic of China
| | - Han Zhang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000 People’s Republic of China
| | - Qiu Liu
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000 People’s Republic of China
| | - Yuanda Song
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, 266 Xincun West Road, Zibo, 255000 People’s Republic of China
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Zhang XY, Li B, Huang BC, Wang FB, Zhang YQ, Zhao SG, Li M, Wang HY, Yu XJ, Liu XY, Jiang J, Wang ZP. Production, Biosynthesis, and Commercial Applications of Fatty Acids From Oleaginous Fungi. Front Nutr 2022; 9:873657. [PMID: 35694158 PMCID: PMC9176664 DOI: 10.3389/fnut.2022.873657] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 03/31/2022] [Indexed: 12/18/2022] Open
Abstract
Oleaginous fungi (including fungus-like protists) are attractive in lipid production due to their short growth cycle, large biomass and high yield of lipids. Some typical oleaginous fungi including Galactomyces geotrichum, Thraustochytrids, Mortierella isabellina, and Mucor circinelloides, have been well studied for the ability to accumulate fatty acids with commercial application. Here, we review recent progress toward fermentation, extraction, of fungal fatty acids. To reduce cost of the fatty acids, fatty acid productions from raw materials were also summarized. Then, the synthesis mechanism of fatty acids was introduced. We also review recent studies of the metabolic engineering strategies have been developed as efficient tools in oleaginous fungi to overcome the biochemical limit and to improve production efficiency of the special fatty acids. It also can be predictable that metabolic engineering can further enhance biosynthesis of fatty acids and change the storage mode of fatty acids.
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Affiliation(s)
- Xin-Yue Zhang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Bing Li
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Bei-Chen Huang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Feng-Biao Wang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Yue-Qi Zhang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Shao-Geng Zhao
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Min Li
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
| | - Hai-Ying Wang
- Key Laboratory of Sustainable Development of Polar Fishery, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
| | - Xin-Jun Yu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Xiao-Yan Liu
- Jiangsu Key Laboratory for Biomass-Based Energy and Enzyme Technology, Huaiyin Normal University, Huaian, China
| | - Jing Jiang
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, China
| | - Zhi-Peng Wang
- School of Marine Science and Engineering, Qingdao Agricultural University, Qingdao, China
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Role of Cytosolic Malic Enzyme in Oleaginicity of High-Lipid-Producing Fungal Strain Mucor circinelloides WJ11. J Fungi (Basel) 2022; 8:jof8030265. [PMID: 35330267 PMCID: PMC8955760 DOI: 10.3390/jof8030265] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 02/25/2022] [Accepted: 03/02/2022] [Indexed: 02/05/2023] Open
Abstract
Mucor circinelloides, an oleaginous filamentous fungus, is gaining popularity due to its ability to synthesize significant amounts of lipids containing γ-linolenic acid (GLA) that have important health benefits. Malic enzyme (ME), which serves as the main source of NADPH in some fungi, has been found to regulate lipid accumulation in oleaginous fungi. In the present study, the role of two cytosolic ME genes, cmalA and cmalB, in the lipid accumulation of the M. circinelloides high-lipid-producing strain WJ11, was evaluated. Strains overexpressing cmalA and cmalB showed a 9.8- and 6.4-fold rise in specific ME activity, respectively, and an elevation of the lipid content by 23.2% and 5.8%, respectively, suggesting that these genes are involved in lipid biosynthesis. Due to increased lipid accumulation, overall GLA content in biomass was observed to be elevated by 11.42% and 16.85% in cmalA and cmalB overexpressing strains, respectively. Our study gives an important insight into different studies exploring the role of the cmalA gene, while we have for the first time investigated the role of the cmalB gene in the M. circinelloides WJ11 strain.
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Lax C, Navarro-Mendoza MI, Pérez-Arques C, Navarro E, Nicolás FE, Garre V. Stable and reproducible homologous recombination enables CRISPR-based engineering in the fungus Rhizopus microsporus. CELL REPORTS METHODS 2021; 1:100124. [PMID: 35475217 PMCID: PMC9017206 DOI: 10.1016/j.crmeth.2021.100124] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 09/20/2021] [Accepted: 11/09/2021] [Indexed: 04/22/2023]
Abstract
Mucormycosis is a lethal and emerging disease that has lacked a genetic model fulfilling both high virulence and the possibility of performing stable and reproducible gene manipulation by homologous recombination (HR). Here, we developed a new methodology to successfully perform HR in Rhizopus microsporus. We isolated an uracil auxotrophic recipient strain and optimized the critical steps in the genetic transformation of this fungus. This was followed by an adaptation of a plasmid-free CRISPR-Cas9 system coupled with microhomology repair templates. We reproducibly generated stable mutants in the genes leuA and crgA, encoding a 3-isopropylmalate dehydratase and an ubiquitin ligase, respectively. Our new genetic model showed that mutations in the gene pyrF, a key virulence gene in several bacterial and fungal pathogens, correlated with an avirulent phenotype in an immunocompetent murine host. This was reverted by gene complementation, showing the broad possibilities of our methodology.
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Affiliation(s)
- Carlos Lax
- Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain
| | | | - Carlos Pérez-Arques
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Eusebio Navarro
- Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain
| | - Francisco Esteban Nicolás
- Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain
| | - Victoriano Garre
- Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain
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Recent Molecular Tools for the Genetic Manipulation of Highly Industrially Important Mucoromycota Fungi. J Fungi (Basel) 2021; 7:jof7121061. [PMID: 34947043 PMCID: PMC8705501 DOI: 10.3390/jof7121061] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/27/2021] [Accepted: 12/06/2021] [Indexed: 12/20/2022] Open
Abstract
Mucorales is the largest and most well-studied order of the phylum Mucormycota and is known for its rapid growth rate and various industrial applications. The Mucorales fungi are a fascinating group of filamentous organisms with many uses in research and the industrial and medical fields. They are widely used biotechnological producers of various secondary metabolites and other value-added products. Certain members of Mucorales are extensively used as model organisms for genetic and molecular investigation and have extended our understanding of the metabolisms of other members of this order as well. Compared with other fungal species, our understanding of Mucoralean fungi is still in its infancy, which could be linked to their lack of effective genetic tools. However, recent advancements in molecular tools and approaches, such as the construction of recyclable markers, silencing vectors, and the CRISPR-Cas9-based gene-editing system, have helped us to modify the genomes of these model organisms. Multiple genetic modifications have been shown to generate valuable products on a large scale and helped us to understand the morphogenesis, basic biology, pathogenesis, and host–pathogen interactions of Mucoralean fungi. In this review, we discuss various conventional and modern genetic tools and approaches used for efficient gene modification in industrially important members of Mucorales.
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Naz T, Yang J, Nosheen S, Sun C, Nazir Y, Mohamed H, Fazili ABA, Ullah S, Li S, Yang W, Garre V, Song Y. Genetic Modification of Mucor circinelloides for Canthaxanthin Production by Heterologous Expression of β-carotene Ketolase Gene. Front Nutr 2021; 8:756218. [PMID: 34722614 PMCID: PMC8548569 DOI: 10.3389/fnut.2021.756218] [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: 08/10/2021] [Accepted: 09/06/2021] [Indexed: 12/21/2022] Open
Abstract
Canthaxanthin is a reddish-orange xanthophyll with strong antioxidant activity and higher bioavailability than carotenes, primarily used in food, cosmetics, aquaculture, and pharmaceutical industries. The spiking market for natural canthaxanthin promoted researchers toward genetic engineering of heterologous hosts for canthaxanthin production. Mucor circinelloides is a dimorphic fungus that produces β-carotene as the major carotenoid and is considered as a model organism for carotenogenic studies. In this study, canthaxanthin-producing M. circinelloides strain was developed by integrating the codon-optimized β-carotene ketolase gene (bkt) of the Haematococcus pluvialis into the genome of the fungus under the control of strong promoter zrt1. First, a basic plasmid was constructed to disrupt crgA gene, a negative regulator of carotene biosynthesis resulted in substantial β-carotene production, which served as the building block for canthaxanthin by further enzymatic reaction of the ketolase enzyme. The genetically engineered strain produced a significant amount (576 ± 28 μg/g) of canthaxanthin, which is the highest amount reported in Mucor to date. Moreover, the cell dry weight of the recombinant strain was also determined, producing up to more than 9.0 g/L, after 96 h. The mRNA expression level of bkt in the overexpressing strain was analyzed by RT-qPCR, which increased by 5.3-, 4.1-, and 3-folds at 24, 48, and 72 h, respectively, compared with the control strain. The canthaxanthin-producing M. circinelloides strain obtained in this study provided a basis for further improving the biotechnological production of canthaxanthin and suggested a useful approach for the construction of more valuable carotenoids, such as astaxanthin.
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Affiliation(s)
- Tahira Naz
- 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
| | - Shaista Nosheen
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Caili Sun
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Yusuf Nazir
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China.,Department of Food Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia
| | - 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
| | - Abu Bakr Ahmad Fazili
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
| | - Samee Ullah
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China.,University Institute of Diet and Nutritional Sciences, Faculty of Allied Health Sciences, The University of Lahore, Lahore, Pakistan
| | - Shaoqi Li
- 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 (Unidad asociada al Instituto de Química Física Rocasolano-Consejo Superior de Investigaciones Científicas (IQFR-CSIC)), Facultad de Biología, Universidad de Murcia, Murcia, Spain
| | - Yuanda Song
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China
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Role of Snf-β in lipid accumulation in the high lipid-producing fungus Mucor circinelloides WJ11. Microb Cell Fact 2021; 20:52. [PMID: 33639948 PMCID: PMC7916304 DOI: 10.1186/s12934-021-01545-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 02/18/2021] [Indexed: 12/23/2022] Open
Abstract
Background Mucor circinelloides WJ11 is a high-lipid producing strain and an excellent producer of γ-linolenic acid (GLA) which is crucial for human health. We have previously identified genes that encode for AMP-activated protein kinase (AMPK) complex in M. circinelloides which is an important regulator for lipid accumulation. Comparative transcriptional analysis between the high and low lipid-producing strains of M. circinelloides showed a direct correlation in the transcriptional level of AMPK genes with lipid metabolism. Thus, the role of Snf-β, which encodes for β subunit of AMPK complex, in lipid accumulation of the WJ11 strain was evaluated in the present study. Results The results showed that lipid content of cell dry weight in Snf-β knockout strain was increased by 32 % (from 19 to 25 %). However, in Snf-β overexpressing strain, lipid content of cell dry weight was decreased about 25 % (from 19 to 14.2 %) compared to the control strain. Total fatty acid analysis revealed that the expression of the Snf-β gene did not significantly affect the fatty acid composition of the strains. However, GLA content in biomass was increased from 2.5 % in control strain to 3.3 % in Snf-β knockout strain due to increased lipid accumulation and decreased to 1.83 % in Snf-β overexpressing strain. AMPK is known to inactivate acetyl-CoA carboxylase (ACC) which catalyzes the rate-limiting step in lipid synthesis. Snf-β manipulation also altered the expression level of the ACC1 gene which may indicate that Snf-β control lipid metabolism by regulating ACC1 gene. Conclusions Our results suggested that Snf-β gene plays an important role in regulating lipid accumulation in M. circinelloides WJ11. Moreover, it will be interesting to evaluate the potential of other key subunits of AMPK related to lipid metabolism. Better insight can show us the way to manipulate these subunits effectively for upscaling the lipid production. Up to our knowledge, it is the first study to investigate the role of Snf-β in lipid accumulation in M. circinelloides.
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Naz T, Nazir Y, Nosheen S, Ullah S, Halim H, Fazili ABA, Li S, Mustafa K, Mohamed H, Yang W, Song Y. Redirecting Metabolic Flux towards the Mevalonate Pathway for Enhanced β-Carotene Production in M. circinelloides CBS 277.49. BIOMED RESEARCH INTERNATIONAL 2020; 2020:8890269. [PMID: 33457420 PMCID: PMC7785371 DOI: 10.1155/2020/8890269] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 11/23/2020] [Accepted: 12/16/2020] [Indexed: 12/18/2022]
Abstract
Carotenoids produced by microbial sources are of industrial and medicinal importance due to their antioxidant and anticancer properties. In the current study, optimization of β-carotene production in M. circinelloides strain 277.49 was achieved using response surface methodology (RSM). Cerulenin and ketoconazole were used to inhibit fatty acids and the sterol biosynthesis pathway, respectively, in order to enhance β-carotene production by diverting metabolic pool towards the mevalonate pathway. All three variables used in screening experiments were found to be significant for the production of β-carotene. The synergistic effect of the C/N ratio, cerulenin, and ketoconazole was further evaluated and optimized for superior β-carotene production using central composite design of RSM. Our results found that the synergistic combination of C/N ratios, cerulenin, and ketoconazole at different concentrations affected the β-carotene productions significantly. The optimal production medium (std. order 11) composed of C/N 25, 10 μg/mL cerulenin, and 150 mg/L ketoconazole, producing maximum β-carotene of 4.26 mg/L (0.43 mg/g) which was 157% greater in comparison to unoptimized medium (1.68 mg/L, 0.17 mg/g). So, it was concluded that metabolic flux had been successfully redirected towards the mevalonate pathway for enhanced β-carotene production in CBS 277.49.
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Affiliation(s)
- Tahira Naz
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
| | - Yusuf Nazir
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
- Department of Food Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia
| | - Shaista Nosheen
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
| | - Samee Ullah
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
- University Institute of Diet and Nutritional Sciences, Faculty of Allied Health Sciences, The University of Lahore, Lahore 54000, Pakistan
| | - Hafiy Halim
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
| | - Abu Bakr Ahmad Fazili
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
| | - Shaoqi Li
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
| | - Kiren Mustafa
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
| | - Hassan Mohamed
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
- Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Assiut 71524, Egypt
| | - Wu Yang
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
| | - Yuanda Song
- Colin Ratledge Center for Microbial Lipids, School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo 255000, China
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