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Liu X, Li K, Yu J, Ma C, Che Q, Zhu T, Li D, Pfeifer BA, Zhang G. Cyclo-diphenylalanine production in Aspergillus nidulans through stepwise metabolic engineering. Metab Eng 2024; 82:147-156. [PMID: 38382797 DOI: 10.1016/j.ymben.2024.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 02/13/2024] [Accepted: 02/18/2024] [Indexed: 02/23/2024]
Abstract
Cyclo-diphenylalanine (cFF) is a symmetrical aromatic diketopiperazine (DKP) found wide-spread in microbes, plants, and resulting food products. As different bioactivities continue being discovered and relevant food and pharmaceutical applications gradually emerge for cFF, there is a growing need for establishing convenient and efficient methods to access this type of compound. Here, we present a robust cFF production system which entailed stepwise engineering of the filamentous fungal strain Aspergillus nidulans A1145 as a heterologous expression host. We first established a preliminary cFF producing strain by introducing the heterologous nonribosomal peptide synthetase (NRPS) gene penP1 to A. nidulans A1145. Key metabolic pathways involving shikimate and aromatic amino acid biosynthetic support were then engineered through a combination of gene deletions of competitive pathway steps, over-expressing feedback-insensitive enzymes in phenylalanine biosynthesis, and introducing a phosphoketolase-based pathway, which diverted glycolytic flux toward the formation of erythrose 4-phosphate (E4P). Through the stepwise engineering of A. nidulans A1145 outlined above, involving both heterologous pathway addition and native pathway metabolic engineering, we were able to produce cFF with titers reaching 611 mg/L in shake flask culture and 2.5 g/L in bench-scale fed-batch bioreactor culture. Our study establishes a production platform for cFF biosynthesis and successfully demonstrates engineering of phenylalanine derived diketopiperazines in a filamentous fungal host.
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Affiliation(s)
- Xiaolin Liu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
| | - Kang Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
| | - Jing Yu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
| | - Chuanteng Ma
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
| | - Qian Che
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
| | - Tianjiao Zhu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China
| | - Dehai Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China; Department for Marine Drugs and Bioproducts, Laoshan Laboratory, Qingdao, 266237, China
| | - Blaine A Pfeifer
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, NY, 14260, United States.
| | - Guojian Zhang
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266003, China; Department for Marine Drugs and Bioproducts, Laoshan Laboratory, Qingdao, 266237, China; Lab of Marine Medicinal Resources Discovery, Marine Biomedical Research Institute of Qingdao, Qingdao, 266075, China.
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2
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Zhu Z, Chen R, Zhang L. Simple phenylpropanoids: recent advances in biological activities, biosynthetic pathways, and microbial production. Nat Prod Rep 2024; 41:6-24. [PMID: 37807808 DOI: 10.1039/d3np00012e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Covering: 2000 to 2023Simple phenylpropanoids are a large group of natural products with primary C6-C3 skeletons. They are not only important biomolecules for plant growth but also crucial chemicals for high-value industries, including fragrances, nutraceuticals, biomaterials, and pharmaceuticals. However, with the growing global demand for simple phenylpropanoids, direct plant extraction or chemical synthesis often struggles to meet current needs in terms of yield, titre, cost, and environmental impact. Benefiting from the rapid development of metabolic engineering and synthetic biology, microbial production of natural products from inexpensive and renewable sources provides a feasible solution for sustainable supply. This review outlines the biological activities of simple phenylpropanoids, compares their biosynthetic pathways in different species (plants, bacteria, and fungi), and summarises key research on the microbial production of simple phenylpropanoids over the last decade, with a focus on engineering strategies that seem to hold most potential for further development. Moreover, constructive solutions to the current challenges and future perspectives for industrial production of phenylpropanoids are presented.
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Affiliation(s)
- Zhanpin Zhu
- Department of Pharmaceutical Botany, School of Pharmacy, Naval Medical University, Shanghai 200433, China.
| | - Ruibing Chen
- Department of Pharmaceutical Botany, School of Pharmacy, Naval Medical University, Shanghai 200433, China.
| | - Lei Zhang
- Department of Pharmaceutical Botany, School of Pharmacy, Naval Medical University, Shanghai 200433, China.
- Institute of Interdisciplinary Integrative Medicine Research, Medical School of Nantong University, Nantong 226001, China
- Innovative Drug R&D Centre, College of Life Sciences, Huaibei Normal University, Huaibei 235000, China
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3
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Ren X, Wei Y, Zhao H, Shao J, Zeng F, Wang Z, Li L. A comprehensive review and comparison of L-tryptophan biosynthesis in Saccharomyces cerevisiae and Escherichia coli. Front Bioeng Biotechnol 2023; 11:1261832. [PMID: 38116200 PMCID: PMC10729320 DOI: 10.3389/fbioe.2023.1261832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 11/22/2023] [Indexed: 12/21/2023] Open
Abstract
L-tryptophan and its derivatives are widely used in the chemical, pharmaceutical, food, and feed industries. Microbial fermentation is the most commonly used method to produce L-tryptophan, which calls for an effective cell factory. The mechanism of L-tryptophan biosynthesis in Escherichia coli, the widely used producer of L-tryptophan, is well understood. Saccharomyces cerevisiae also plays a significant role in the industrial production of biochemicals. Because of its robustness and safety, S. cerevisiae is favored for producing pharmaceuticals and food-grade biochemicals. However, the biosynthesis of L-tryptophan in S. cerevisiae has been rarely summarized. The synthetic pathways and engineering strategies of L-tryptophan in E. coli and S. cerevisiae have been reviewed and compared in this review. Furthermore, the information presented in this review pertains to the existing understanding of how L-tryptophan affects S. cerevisiae's stress fitness, which could aid in developing a novel plan to produce more resilient industrial yeast and E. coli cell factories.
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Affiliation(s)
- Xinru Ren
- College of Science and Technology, Hebei Agricultural University, Cangzhou, China
| | - Yue Wei
- College of Science and Technology, Hebei Agricultural University, Cangzhou, China
| | - Honglu Zhao
- College of Science and Technology, Hebei Agricultural University, Cangzhou, China
| | - Juanjuan Shao
- College of Science and Technology, Hebei Agricultural University, Cangzhou, China
| | - Fanli Zeng
- College of Life Sciences, Hebei Agricultural University, Baoding, China
- Hebei Key Laboratory of Analysis and Control of Zoonotic Pathogenic Microorganism, Baoding, China
| | - Zhen Wang
- College of Science and Technology, Hebei Agricultural University, Cangzhou, China
- Hebei Key Laboratory of Analysis and Control of Zoonotic Pathogenic Microorganism, Baoding, China
| | - Li Li
- College of Science and Technology, Hebei Agricultural University, Cangzhou, China
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4
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Effendi SSW, Ng IS. Challenges and opportunities for engineered Escherichia coli as a pivotal chassis toward versatile tyrosine-derived chemicals production. Biotechnol Adv 2023; 69:108270. [PMID: 37852421 DOI: 10.1016/j.biotechadv.2023.108270] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 08/30/2023] [Accepted: 10/11/2023] [Indexed: 10/20/2023]
Abstract
Growing concerns over limited fossil resources and associated environmental problems are motivating the development of sustainable processes for the production of high-volume fuels and high-value-added compounds. The shikimate pathway, an imperative pathway in most microorganisms, is branched with tyrosine as the rate-limiting step precursor of valuable aromatic substances. Such occurrence suggests the shikimate pathway as a promising route in developing microbial cell factories with multiple applications in the nutraceutical, pharmaceutical, and chemical industries. Therefore, an increasing number of studies have focused on this pathway to enable the biotechnological manufacture of pivotal and versatile aromatic products. With advances in genome databases and synthetic biology tools, genetically programmed Escherichia coli strains are gaining immense interest in the sustainable synthesis of chemicals. Engineered E. coli is expected to be the next bio-successor of fossil fuels and plants in commercial aromatics synthesis. This review summarizes successful and applicable genetic and metabolic engineering strategies to generate new chassis and engineer the iterative pathway of the tyrosine route in E. coli, thus addressing the opportunities and current challenges toward the realization of sustainable tyrosine-derived aromatics.
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Affiliation(s)
| | - I-Son Ng
- Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan.
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Chong Y, Kim BG, Park YJ, Yang Y, Lee SW, Lee Y, Ahn JH. Production of Four Flavonoid C-Glucosides in Escherichia coli. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:5302-5313. [PMID: 36952620 DOI: 10.1021/acs.jafc.3c00297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Flavonoid C-glucosides, which are found in several plant families, are characterized by several biological properties, including antioxidant, anticancer, anti-inflammatory, neuroprotective, hepatoprotective, cardioprotective, antibacterial, antihyperalgesic, antiviral, and antinociceptive activities. The biosynthetic pathway of flavonoid C-glucosides in plants has been elucidated. In the present study, a pathway was introduced to Escherichia coli to synthesize four flavonoid C-glucosides, namely, isovitexin, vitexin, kaempferol 6-C-glucoside, and kaempferol 8-C-glucoside. A five- or six-step metabolic pathway for synthesizing flavonoid aglycones from tyrosine was constructed and two regioselective flavonoid C-glycosyltransferases from Wasabia japonica (WjGT1) and Trollius chinensis (TcCGT) were used. Additionally, the best shikimate gene module construct was selected to maximize the titer of each C-glucoside flavonoid. Isovitexin (30.2 mg/L), vitexin (93.9 mg/L), kaempferol 6-C-glucoside (14.4 mg/L), and kaempferol 8-C-glucoside (38.6 mg/L) were synthesized using these approaches. The flavonoid C-glucosides synthesized in this study provide a basis for investigating and unraveling their novel biological properties.
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Affiliation(s)
- Yoojin Chong
- Department of Integrative Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 05029, Republic of Korea
| | - Bong-Gyu Kim
- Department of Forest Resources, Gyeongsang National University, 33 Dongjin-ro, Jinju-si, Gyeongsangman-do 52725, Republic of Korea
| | - Yeo-Jin Park
- Department of Integrative Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 05029, Republic of Korea
| | - Youri Yang
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Shin-Won Lee
- Department of Integrative Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 05029, Republic of Korea
| | - Youngshim Lee
- Department of Integrative Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 05029, Republic of Korea
| | - Joong-Hoon Ahn
- Department of Integrative Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 05029, Republic of Korea
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Zhang P, Gao J, Zhang H, Wang Y, Liu Z, Lee SY, Mao X. Metabolic engineering of Escherichia coli for the production of an antifouling agent zosteric acid. Metab Eng 2023; 76:247-259. [PMID: 36822462 DOI: 10.1016/j.ymben.2023.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/13/2023] [Accepted: 02/19/2023] [Indexed: 02/23/2023]
Abstract
Zosteric acid (ZA) is a Zostera species-derived, sulfated phenolic acid compound with antifouling activity and has gained much attention due to its nontoxic and biodegradable characteristics. However, the yield of Zostera species available for ZA extraction is limited by natural factors, such as season, latitude, light, and temperature. Here we report the development of metabolically engineered Escherichia coli strains capable of producing ZA from glucose and glycerol. First, intracellular availability of the sulfur donor 3'-phosphoadenosine-5'-phosphosulfate (PAPS) was enhanced by knocking out the cysH gene responsible for PAPS consumption and overexpressing the genes required for PAPS biosynthesis. Co-overexpression of the genes encoding tyrosine ammonia-lyase, sulfotransferase 1A1, ATP sulfurylase, and adenosine 5'-phosphosulfate kinase constructed ZA producing strain with enhanced PAPS supply. Second, the feedback-resistant forms of aroG and tyrA genes (encoding 3-deoxy-d-arabinoheptulosonate 7-phosphate synthase and chorismate mutase, respectively) were overexpressed to relieve the feedback regulation of L-tyrosine biosynthesis. Third, the pykA gene involved in phosphoenolpyruvate-consuming reaction, the regulator gene tyrR, the competing pathway gene pheA, and the ptsHIcrr genes essential for the PEP:carbohydrate phosphotransferase system were deleted. Moreover, all genes involved in the shikimate pathway and the talA, tktA, and tktB genes in the pentose phosphate pathway were examined for ZA production. The PTS-independent glucose uptake system, the expression vector system, and the carbon source were also optimized. As a result, the best-performing strain successfully produced 1.52 g L-1 ZA and 1.30 g L-1p-hydroxycinnamic acid from glucose and glycerol in a 700 mL fed-batch bioreactor.
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Affiliation(s)
- Peichao Zhang
- Qingdao Key Laboratory of Food Biotechnology, College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Jing Gao
- Qingdao Key Laboratory of Food Biotechnology, College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Haiyang Zhang
- Qingdao Key Laboratory of Food Biotechnology, College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Yongzhen Wang
- Qingdao Key Laboratory of Food Biotechnology, College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Zhen Liu
- Qingdao Key Laboratory of Food Biotechnology, College of Food Science and Engineering, Ocean University of China, Qingdao, China
| | - Sang Yup Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Four), BioProcess Engineering Research Center, Institute for the BioCentury, KAIST, Daejeon, Republic of Korea.
| | - Xiangzhao Mao
- Qingdao Key Laboratory of Food Biotechnology, College of Food Science and Engineering, Ocean University of China, Qingdao, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
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7
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Lu L, Wang X, Zhou L, Liu Q, Zhang G, Xue B, Hu C, Shen X, Sun X, Yan Y, Wang J, Yuan Q. Establishing biosynthetic pathway for the production of p-hydroxyacetophenone and its glucoside in Escherichia coli. Metab Eng 2023; 76:110-119. [PMID: 36746296 DOI: 10.1016/j.ymben.2023.02.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 01/10/2023] [Accepted: 02/03/2023] [Indexed: 02/05/2023]
Abstract
p-Hydroxyacetophenone (p-HAP) and its glucoside picein are plant-derived natural products that have been extensively used in chemical, pharmaceutical and cosmetic industries owing to their antioxidant, antibacterial and antiseptic activities. However, the natural biosynthetic pathways for p-HAP and picein have yet been resolved so far, limiting their biosynthesis in microorganisms. In this study, we design and construct a biosynthetic pathway for de novo production of p-HAP and picein from glucose in E. coli. First, screening and characterizing pathway enzymes enable us to successfully establish functional biosynthetic pathway for p-HAP production. Then, the rate-limiting step in the pathway caused by a reversible alcohol dehydrogenase is completely eliminated by modulating intracellular redox cofactors. Subsequent host strain engineering via systematic increase of precursor supplies enables production enhancement of p-HAP with a titer of 1445.3 mg/L under fed-batch conditions. Finally, a novel p-HAP glucosyltransferase capable of generating picein from p-HAP is identified and characterized from a series of glycosyltransferases. On this basis, de novo biosynthesis of picein from glucose is achieved with a titer of 210.7 mg/L under fed-batch conditions. This work not only demonstrates a microbial platform for p-HAP and picein synthesis, but also represents a generalizable pathway design strategy to produce value-added compounds.
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Affiliation(s)
- Liangyu Lu
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Xiaolei Wang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Lei Zhou
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Qiyuan Liu
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Guanghao Zhang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Bingqing Xue
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Chenyu Hu
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Xiaolin Shen
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Xinxiao Sun
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Yajun Yan
- College of Engineering, The University of Georgia, Athens, GA, 30602, USA
| | - Jia Wang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
| | - Qipeng Yuan
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
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8
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De novo Biosynthesis of 2-Phenylacetamide in Engineered Escherichia coli. Biochem Eng J 2023. [DOI: 10.1016/j.bej.2023.108882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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9
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Sheng Q, Yi L, Zhong B, Wu X, Liu L, Zhang B. Shikimic acid biosynthesis in microorganisms: Current status and future direction. Biotechnol Adv 2023; 62:108073. [PMID: 36464143 DOI: 10.1016/j.biotechadv.2022.108073] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 11/03/2022] [Accepted: 11/28/2022] [Indexed: 12/05/2022]
Abstract
Shikimic acid (SA), a hydroaromatic natural product, is used as a chiral precursor for organic synthesis of oseltamivir (Tamiflu®, an antiviral drug). The process of microbial production of SA has recently undergone vigorous development. Particularly, the sustainable construction of recombinant Corynebacterium glutamicum (141.2 g/L) and Escherichia coli (87 g/L) laid a solid foundation for the microbial fermentation production of SA. However, its industrial application is restricted by limitations such as the lack of fermentation tests for industrial-scale and the requirement of growth-limiting factors, antibiotics, and inducers. Therefore, the development of SA biosensors and dynamic molecular switches, as well as genetic modification strategies and optimization of the fermentation process based on omics technology could improve the performance of SA-producing strains. In this review, recent advances in the development of SA-producing strains, including genetic modification strategies, metabolic pathway construction, and biosensor-assisted evolution, are discussed and critically reviewed. Finally, future challenges and perspectives for further reinforcing the development of robust SA-producing strains are predicted, providing theoretical guidance for the industrial production of SA.
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Affiliation(s)
- Qi Sheng
- College of Bioscience and Bioengineering, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Nanchang 330045, China; Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang 330045, China
| | - Lingxin Yi
- College of Bioscience and Bioengineering, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Nanchang 330045, China; Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang 330045, China
| | - Bin Zhong
- College of Bioscience and Bioengineering, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Nanchang 330045, China; Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang 330045, China
| | - Xiaoyu Wu
- College of Bioscience and Bioengineering, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Nanchang 330045, China; Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang 330045, China
| | - Liming Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
| | - Bin Zhang
- College of Bioscience and Bioengineering, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Nanchang 330045, China; Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang 330045, China.
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Linke JA, Rayat A, Ward JM. Production of indigo by recombinant bacteria. BIORESOUR BIOPROCESS 2023; 10:20. [PMID: 36936720 PMCID: PMC10011309 DOI: 10.1186/s40643-023-00626-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 01/06/2023] [Indexed: 03/15/2023] Open
Abstract
Indigo is an economically important dye, especially for the textile industry and the dyeing of denim fabrics for jeans and garments. Around 80,000 tonnes of indigo are chemically produced each year with the use of non-renewable petrochemicals and the use and generation of toxic compounds. As many microorganisms and their enzymes are able to synthesise indigo after the expression of specific oxygenases and hydroxylases, microbial fermentation could offer a more sustainable and environmentally friendly manufacturing platform. Although multiple small-scale studies have been performed, several existing research gaps still hinder the effective translation of these biochemical approaches. No article has evaluated the feasibility and relevance of the current understanding and development of indigo biocatalysis for real-life industrial applications. There is no record of either established or practically tested large-scale bioprocess for the biosynthesis of indigo. To address this, upstream and downstream processing considerations were carried out for indigo biosynthesis. 5 classes of potential biocatalysts were identified, and 2 possible bioprocess flowsheets were designed that facilitate generating either a pre-reduced dye solution or a dry powder product. Furthermore, considering the publicly available data on the development of relevant technology and common bioprocess facilities, possible platform and process values were estimated, including titre, DSP yield, potential plant capacities, fermenter size and batch schedule. This allowed us to project the realistic annual output of a potential indigo biosynthesis platform as 540 tonnes. This was interpreted as an industrially relevant quantity, sufficient to provide an annual dye supply to a single industrial-size denim dyeing plant. The conducted sensitivity analysis showed that this anticipated output is most sensitive to changes in the reaction titer, which can bring a 27.8% increase or a 94.4% drop. Thus, although such a biological platform would require careful consideration, fine-tuning and optimization before real-life implementation, the recombinant indigo biosynthesis was found as already attractive for business exploitation for both, luxury segment customers and mass-producers of denim garments. Graphical Abstract Supplementary Information The online version contains supplementary material available at 10.1186/s40643-023-00626-7.
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Affiliation(s)
- Julia A. Linke
- grid.83440.3b0000000121901201Chemical Engineering Department, University College London (UCL), Torrington Place, London, WC1E 7JE UK
- grid.83440.3b0000000121901201Division of Medicine, University College London (UCL), 5 University Street, London, WC1E 6JF UK
| | - Andrea Rayat
- grid.83440.3b0000000121901201Biochemical Engineering Department, University College London (UCL), Gower St., London, WC1E 6BT UK
| | - John M. Ward
- grid.83440.3b0000000121901201Biochemical Engineering Department, University College London (UCL), Gower St., London, WC1E 6BT UK
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11
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Sieow BFL, De Sotto R, Seet ZRD, Hwang IY, Chang MW. Synthetic Biology Meets Machine Learning. Methods Mol Biol 2023; 2553:21-39. [PMID: 36227537 DOI: 10.1007/978-1-0716-2617-7_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
This chapter outlines the myriad applications of machine learning (ML) in synthetic biology, specifically in engineering cell and protein activity, and metabolic pathways. Though by no means comprehensive, the chapter highlights several prominent computational tools applied in the field and their potential use cases. The examples detailed reinforce how ML algorithms can enhance synthetic biology research by providing data-driven insights into the behavior of living systems, even without detailed knowledge of their underlying mechanisms. By doing so, ML promises to increase the efficiency of research projects by modeling hypotheses in silico that can then be tested through experiments. While challenges related to training dataset generation and computational costs remain, ongoing improvements in ML tools are paving the way for smarter and more streamlined synthetic biology workflows that can be readily employed to address grand challenges across manufacturing, medicine, engineering, agriculture, and beyond.
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Affiliation(s)
- Brendan Fu-Long Sieow
- NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, Singapore, Singapore
- Synthetic Biology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- NUS Graduate School for Integrative Sciences and Engineering Programme, National University of Singapore, Singapore, Singapore
| | - Ryan De Sotto
- NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, Singapore, Singapore
- Synthetic Biology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Zhi Ren Darren Seet
- NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, Singapore, Singapore
- Synthetic Biology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - In Young Hwang
- NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, Singapore, Singapore
- Synthetic Biology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Matthew Wook Chang
- NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), National University of Singapore, Singapore, Singapore.
- Synthetic Biology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
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12
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Liu Y, Song D, Hu H, Yang R, Lyu X. De Novo Production of Hydroxytyrosol by Saccharomyces cerevisiae-Escherichia coli Coculture Engineering. ACS Synth Biol 2022; 11:3067-3077. [PMID: 35952699 DOI: 10.1021/acssynbio.2c00300] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Hydroxytyrosol is a valuable plant-derived phenolic compound with excellent pharmacological activities for application in the food and health care industries. Microbial biosynthesis provides a promising approach for sustainable production of hydroxytyrosol via metabolic engineering. However, its efficient production is limited by the machinery and resources available in the commonly used individual microbial platform, for example, Escherichia coli, Saccharomyces cerevisiae. In this study, a S. cerevisiae-E. coli coculture system was designed for de novo biosynthesis of hydroxytyrosol by taking advantage of their inherent metabolic properties, whereby S. cerevisiae was engineered for de novo production of tyrosol based on an endogenous Ehrlich pathway, and E. coli was dedicated to converting tyrosol to hydroxytyrosol by use of native hydroxyphenylacetate 3-monooxygenase (EcHpaBC). To enhance hydroxytyrosol production, intra- and intermodule engineering was employed in this microbial consortium: (I) in the upstream S. cerevisiae strain, multipath regulations combining with a glucose-sensitive GAL regulation system were engineered to enhance the precursor supply, resulting in significant increase of tyrosol production (from 17.60 mg/L to 461.07 mg/L); (II) Echpabc was overexpressed in the downstream E. coli strain, improving the conversion rate of tyrosol to hydroxytyrosol from 0.03% to 86.02%; (III) and last, intermodule engineering with this coculture system was performed by optimization of the initial inoculation ratio of each population and fermentation conditions, achieving 435.32 mg/L of hydroxytyrosol. This S. cerevisiae-E. coli coculture strategy provides a new opportunity for de novo production of hydroxytyrosol from inexpensive feedstock.
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Affiliation(s)
- Yingjie Liu
- School of Food Science and Technology, Jiangnan University, 214122, Wuxi, P. R. China
| | - Dong Song
- Jiangxi Baiyue Food Co. Ltd, Pingxiang, Jiangxi 337000, P. R. China
| | - Haitao Hu
- School of Food Science and Technology, Jiangnan University, 214122, Wuxi, P. R. China
| | - Ruijin Yang
- School of Food Science and Technology, Jiangnan University, 214122, Wuxi, P. R. China.,Jiangnan University (Rugao) Institute of Food Biotechnology, 226503, Nantong, P. R. China
| | - Xiaomei Lyu
- School of Food Science and Technology, Jiangnan University, 214122, Wuxi, P. R. China.,Jiangnan University (Rugao) Institute of Food Biotechnology, 226503, Nantong, P. R. China
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13
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Liu Y, Liu H, Hu H, Ng KR, Yang R, Lyu X. De Novo Production of Hydroxytyrosol by Metabolic Engineering of Saccharomyces cerevisiae. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:7490-7499. [PMID: 35649155 DOI: 10.1021/acs.jafc.2c02137] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Hydroxytyrosol is an olive-derived phenolic compound of increasing commercial interest due to its health-promoting properties. In this study, a high-yield hydroxytyrosol-producing Saccharomyces cerevisiae cell factory was established via a comprehensive metabolic engineering scheme. First, de novo biosynthetic pathway of hydroxytyrosol was constructed in yeast by gene screening and overexpression of different phenol hydroxylases, among which paHD (from Pseudomonas aeruginosa) displayed the best catalytic performance. Next, hydroxytyrosol precursor supply was enhanced via a multimodular engineering approach: elimination of tyrosine feedback inhibition through genomic integration of aro4K229L and aro7G141S, construction of an aromatic aldehyde synthase (AAS)-based tyrosine metabolic pathway, and redistribution of metabolic flux between glycolytic pathway and pentose phosphate pathway (PPP) by introducing the exogenous gene Bbxfpkopt. As a result, the titer of hydroxytyrosol was improved by 6.88-fold. Finally, a glucose-responsive dynamic regulation system based on GAL80 deletion was implemented, resulting in the final hydroxytyrosol yields of 308.65 mg/L and 167.98 mg/g cell mass, the highest known from de novo production in S. cerevisiae to date.
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Affiliation(s)
- Yingjie Liu
- School of Food Science and Technology, Jiangnan University, 214122 Wuxi, China
| | - Han Liu
- School of Food Science and Technology, Jiangnan University, 214122 Wuxi, China
| | - Haitao Hu
- School of Food Science and Technology, Jiangnan University, 214122 Wuxi, China
| | - Kuan Rei Ng
- Food Science and Technology Programme, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore
| | - Ruijin Yang
- School of Food Science and Technology, Jiangnan University, 214122 Wuxi, China
| | - Xiaomei Lyu
- School of Food Science and Technology, Jiangnan University, 214122 Wuxi, China
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14
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Wang XH, Zhao C, Lu XY, Zong H, Zhuge B. Production of Caffeic Acid with Co-fermentation of Xylose and Glucose by Multi-modular Engineering in Candida glycerinogenes. ACS Synth Biol 2022; 11:900-908. [PMID: 35138824 DOI: 10.1021/acssynbio.1c00535] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Caffeic acid (CA), a natural phenolic compound, has important medicinal value and market potential. In this study, we report a metabolic engineering strategy for the biosynthesis of CA in Candida glycerinogenes using xylose and glucose. The availability of precursors was increased by optimization of the shikimate (SA) pathway and the aromatic amino acid pathway. Subsequently, the carbon flux into the SA pathway was maximized by introducing a xylose metabolic pathway and optimizing the xylose assimilation pathway. Eventually, a high yielding strain CG19 was obtained, which reached a yield of 4.61 mg/g CA from mixed sugar, which was 1.2-fold higher than that of glucose. The CA titer in the 5 L bioreactor reached 431.45 mg/L with a yield of 8.63 mg/g of mixed sugar. These promising results demonstrate the great advantages of mixed sugar over glucose for high-yield production of CA. This is the first report to produce CA in C. glycerinogenes with xylose and glucose as carbon sources, which developed a promising strategy for the efficient production of high-value aromatic compounds.
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Affiliation(s)
- Xi-Hui Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Research Centre of Industrial Microbiology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Cui Zhao
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Research Centre of Industrial Microbiology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Xin-Yao Lu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Research Centre of Industrial Microbiology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Hong Zong
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Research Centre of Industrial Microbiology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Bin Zhuge
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Research Centre of Industrial Microbiology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
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15
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Advances in microbial production of feed amino acid. ADVANCES IN APPLIED MICROBIOLOGY 2022; 119:1-33. [DOI: 10.1016/bs.aambs.2022.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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16
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Improved production of the non-native cofactor F 420 in Escherichia coli. Sci Rep 2021; 11:21774. [PMID: 34741069 PMCID: PMC8571402 DOI: 10.1038/s41598-021-01224-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Accepted: 10/21/2021] [Indexed: 11/17/2022] Open
Abstract
The deazaflavin cofactor F420 is a low-potential, two-electron redox cofactor produced by some Archaea and Eubacteria that is involved in methanogenesis and methanotrophy, antibiotic biosynthesis, and xenobiotic metabolism. However, it is not produced by bacterial strains commonly used for industrial biocatalysis or recombinant protein production, such as Escherichia coli, limiting our ability to exploit it as an enzymatic cofactor and produce it in high yield. Here we have utilized a genome-scale metabolic model of E. coli and constraint-based metabolic modelling of cofactor F420 biosynthesis to optimize F420 production in E. coli. This analysis identified phospho-enol pyruvate (PEP) as a limiting precursor for F420 biosynthesis, explaining carbon source-dependent differences in productivity. PEP availability was improved by using gluconeogenic carbon sources and overexpression of PEP synthase. By improving PEP availability, we were able to achieve a ~ 40-fold increase in the space–time yield of F420 compared with the widely used recombinant Mycobacterium smegmatis expression system. This study establishes E. coli as an industrial F420-production system and will allow the recombinant in vivo use of F420-dependent enzymes for biocatalysis and protein engineering applications.
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17
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Xiong B, Zhu Y, Tian D, Jiang S, Fan X, Ma Q, Wu H, Xie X. Flux redistribution of central carbon metabolism for efficient production of l-tryptophan in Escherichia coli. Biotechnol Bioeng 2021; 118:1393-1404. [PMID: 33399214 DOI: 10.1002/bit.27665] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/24/2020] [Accepted: 12/30/2020] [Indexed: 01/22/2023]
Abstract
Microbial production of l-tryptophan (l-trp) has received considerable attention because of its diverse applications in food additives and pharmaceuticals. Overexpression of rate-limiting enzymes and blockage of competing pathways can effectively promote microbial production of l-trp. However, the biosynthetic process remains suboptimal due to imbalanced flux distribution between central carbon and tryptophan metabolism, presenting a major challenge to further improvement of l-trp yield. In this study, we redistributed central carbon metabolism to improve phosphoenolpyruvate (PEP) and erythrose-4-phosphate (E4P) pools in an l-trp producing strain of Escherichia coli for efficient l-trp synthesis. To do this, a phosphoketolase from Bifidobacterium adolescentis was introduced to strengthen E4P formation, and the l-trp titer and yield increased to 10.8 g/L and 0.148 g/g glucose, respectively. Next, the phosphotransferase system was substituted with PEP-independent glucose transport, meditated by a glucose facilitator from Zymomonas mobilis and native glucokinase. This modification improved l-trp yield to 0.164 g/g glucose, concomitant with 58% and 40% decreases of acetate and lactate accumulation, respectively. Then, to channel more central carbon flux to the tryptophan biosynthetic pathway, several metabolic engineering strategies were applied to rewire the PEP-pyruvate-oxaloacetate node. Finally, the constructed strain SX11 produced 41.7 g/L l-trp with an overall yield of 0.227 g/g glucose after 40 h fed-batch fermentation in 5-L bioreactor. This is the highest overall yield of l-trp ever reported from a rationally engineered strain. Our results suggest the flux redistribution of central carbon metabolism to maintain sufficient supply of PEP and E4P is a promising strategy for efficient l-trp biosynthesis, and this strategy would likely also increase the production of other aromatic amino acids and derivatives.
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Affiliation(s)
- Bo Xiong
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science & Technology, Tianjin, China.,College of Biotechnology, Tianjin University of Science & Technology, Tianjin, China
| | - Yongduo Zhu
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science & Technology, Tianjin, China.,College of Biotechnology, Tianjin University of Science & Technology, Tianjin, China
| | - Daoguang Tian
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science & Technology, Tianjin, China.,College of Biotechnology, Tianjin University of Science & Technology, Tianjin, China
| | - Shuai Jiang
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science & Technology, Tianjin, China.,College of Biotechnology, Tianjin University of Science & Technology, Tianjin, China
| | - Xiaoguang Fan
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science & Technology, Tianjin, China.,College of Biotechnology, Tianjin University of Science & Technology, Tianjin, China
| | - Qian Ma
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science & Technology, Tianjin, China.,College of Biotechnology, Tianjin University of Science & Technology, Tianjin, China
| | - Heyun Wu
- College of Food Science and Engineering, Tianjin University of Science & Technology, Tianjin, China
| | - Xixian Xie
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science & Technology, Tianjin, China.,College of Biotechnology, Tianjin University of Science & Technology, Tianjin, China
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18
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Rajkumar AS, Morrissey JP. Rational engineering of Kluyveromyces marxianus to create a chassis for the production of aromatic products. Microb Cell Fact 2020; 19:207. [PMID: 33176787 PMCID: PMC7659061 DOI: 10.1186/s12934-020-01461-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 10/27/2020] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND The yeast Kluyveromyces marxianus offers unique potential for industrial biotechnology because of useful features like rapid growth, thermotolerance and a wide substrate range. As an emerging alternative platform, K. marxianus requires the development and validation of metabolic engineering strategies to best utilise its metabolism as a basis for bio-based production. RESULTS To illustrate the synthetic biology strategies to be followed and showcase its potential, we describe a comprehensive approach to rationally engineer a metabolic pathway in K. marxianus. We use the phenylalanine biosynthetic pathway both as a prototype and because phenylalanine is a precursor for commercially valuable secondary metabolites. First, we modify and overexpress the pathway to be resistant to feedback inhibition so as to overproduce phenylalanine de novo from synthetic minimal medium. Second, we assess native and heterologous means to increase precursor supply to the biosynthetic pathway. Finally, we eliminate branch points and competing reactions in the pathway and rebalance precursors to redirect metabolic flux to a specific product, 2-phenylethanol (2-PE). As a result, we are able to construct robust strains capable of producing over 800 mg L-1 2-PE from minimal medium. CONCLUSIONS The strains we constructed are a promising platform for the production of aromatic amino acid-based biochemicals, and our results illustrate challenges with attempting to combine individually beneficial modifications in an integrated platform.
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Affiliation(s)
- Arun S Rajkumar
- School of Microbiology, Centre for Synthetic Biology and Biotechnology, Environmental Research Institute, APC Microbiome Institute, University College Cork, Cork, T12 K8AF, Ireland
| | - John P Morrissey
- School of Microbiology, Centre for Synthetic Biology and Biotechnology, Environmental Research Institute, APC Microbiome Institute, University College Cork, Cork, T12 K8AF, Ireland.
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19
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Niu FX, He X, Huang YB, Liu JZ. Biosensor-Guided Atmospheric and Room-Temperature Plasma Mutagenesis and Shuffling for High-Level Production of Shikimic Acid from Sucrose in Escherichia coli. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:11765-11773. [PMID: 33030899 DOI: 10.1021/acs.jafc.0c05253] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Here, we first developed a combined strain improvement strategy of biosensor-guided atmospheric and room-temperature plasma mutagenesis and genome shuffling. Application of this strategy resulted in a 2.7-fold increase in the production of shikimic acid (SA) and a 2.0-fold increase in growth relative to those of the starting strain. Whole-cell resequencing of the shuffled strain and confirmation using CRISPRa/CRISPRi revealed that some membrane protein-related mutant genes are identified as being closely related to the higher SA titer. The engineered shuffling strain produced 18.58 ± 0.56 g/L SA from glucose with a yield of 68% (mol/mol) by fed-batch whole-cell biocatalysis, achieving 79% of the theoretical maximum. Sucrose-utilizing Escherichia coli was engineered for SA production by introducing Mannheimia succiniciproducens β-fructofuranosidase gene. The resulting sucrose-utilizing E. coli strain produced 24.64 ± 0.32 g/L SA from sucrose with a yield of 1.42 mol/mol by fed-batch whole-cell biocatalysis, achieving 83% of the theoretical maximum.
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Affiliation(s)
- Fu-Xing Niu
- Institute of Synthetic Biology, MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Xin He
- Institute of Synthetic Biology, MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Yuan-Bin Huang
- Institute of Synthetic Biology, MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Jian-Zhong Liu
- Institute of Synthetic Biology, MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
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20
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Zhang J, Petersen SD, Radivojevic T, Ramirez A, Pérez-Manríquez A, Abeliuk E, Sánchez BJ, Costello Z, Chen Y, Fero MJ, Martin HG, Nielsen J, Keasling JD, Jensen MK. Combining mechanistic and machine learning models for predictive engineering and optimization of tryptophan metabolism. Nat Commun 2020; 11:4880. [PMID: 32978375 PMCID: PMC7519671 DOI: 10.1038/s41467-020-17910-1] [Citation(s) in RCA: 108] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 07/27/2020] [Indexed: 12/23/2022] Open
Abstract
Through advanced mechanistic modeling and the generation of large high-quality datasets, machine learning is becoming an integral part of understanding and engineering living systems. Here we show that mechanistic and machine learning models can be combined to enable accurate genotype-to-phenotype predictions. We use a genome-scale model to pinpoint engineering targets, efficient library construction of metabolic pathway designs, and high-throughput biosensor-enabled screening for training diverse machine learning algorithms. From a single data-generation cycle, this enables successful forward engineering of complex aromatic amino acid metabolism in yeast, with the best machine learning-guided design recommendations improving tryptophan titer and productivity by up to 74 and 43%, respectively, compared to the best designs used for algorithm training. Thus, this study highlights the power of combining mechanistic and machine learning models to effectively direct metabolic engineering efforts.
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Affiliation(s)
- Jie Zhang
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs., Lyngby, Denmark
| | - Søren D Petersen
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs., Lyngby, Denmark
| | - Tijana Radivojevic
- Joint BioEnergy Institute, Emeryville, CA, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- DOE Agile BioFoundry, Emeryville, CA, USA
| | | | | | | | - Benjamín J Sánchez
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs., Lyngby, Denmark
| | - Zak Costello
- Joint BioEnergy Institute, Emeryville, CA, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- DOE Agile BioFoundry, Emeryville, CA, USA
| | - Yu Chen
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, Gothenburg, Sweden
| | | | - Hector Garcia Martin
- Joint BioEnergy Institute, Emeryville, CA, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- DOE Agile BioFoundry, Emeryville, CA, USA
- BCAM, Basque Center for Applied Mathematics, Bilbao, Spain
| | - Jens Nielsen
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs., Lyngby, Denmark
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
- BioInnovation Institute, Ole Maaløes Vej 3, DK-2200, Copenhagen N, Denmark
| | - Jay D Keasling
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs., Lyngby, Denmark
- Joint BioEnergy Institute, Emeryville, CA, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Chemical and Biomolecular Engineering & Department of Bioengineering, University of California, Berkeley, CA, USA
- Center for Synthetic Biochemistry, Institute for Synthetic Biology, Shenzhen Institutes of Advanced Technologies, Shenzhen, China
| | - Michael K Jensen
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs., Lyngby, Denmark.
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21
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Zhang K, Mohsin A, Yu J, Hu Y, Ali MF, Chen Z, Zhuang Y, Chu J, Guo M. Two-Component-System RspA1/A2-Dependent Regulation on Primary Metabolism in Streptomyces albus A30 Cultivated With Glutamate as the Sole Nitrogen Source. Front Microbiol 2020; 11:1658. [PMID: 32849342 PMCID: PMC7411085 DOI: 10.3389/fmicb.2020.01658] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 06/25/2020] [Indexed: 11/13/2022] Open
Abstract
In our previous study, a two-component-system (TCS) RspA1/A2 was identified and proven to play a positive role in the regulation of salinomycin (antibiotic) biosynthesis in Streptomyces albus. However, the regulatory mechanism of RspA1/A2 using a carbon source (glucose or acetate) for the cell growth of S. albus is still unclear till present research work. Therefore, in this work, the mechanistic pathway of RspA1/A2 on carbon source metabolism is unveiled. Firstly, this work reports that the response regulator RspA1 gene rspA1 knocked-out mutant ΔrspA1 exhibits lower biomass accumulation and lower glucose consumption rates as compared to the parental strain A30 when cultivated in a defined minimal medium (MM) complemented with 75 mM glutamate. Further, it is demonstrated that the regulation of TCS RspA1/A2 on the phosphoenolpyruvate-pyruvate-oxaloacetate node results in decreasing the intracellular acetyl-CoA pool in mutant ΔrspA1. Subsequently, it was verified that the RspA1 could not only directly interact with the promoter regions of key genes encoding AMP-forming acetyl-CoA synthase (ACS), citrate synthase (CS), and pyruvate dehydrogenase complex (PDH) but also bind promoter regions of the genes pyc, pck, and glpX in gluconeogenesis. In addition, the transcriptomic data analysis showed that pyruvate and glutamate transformations supported robust TCS RspA1/A2-dependent regulation of glucose metabolism, which led to a decreased flux of pyruvate into the TCA cycle and an increased flux of gluconeogenesis pathway in mutant ΔrspA1. Finally, a new transcriptional regulatory network of TCS RspA1/A2 on primary metabolism across central carbon metabolic pathways including the glycolysis pathway, TCA cycle, and gluconeogenesis pathway is proposed.
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Affiliation(s)
- Kuipu Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Ali Mohsin
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Junxiong Yu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Yuwen Hu
- College of Food Science and Technology, Nanchang University, Nanchang, China
| | - Muhammad Fahad Ali
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | | | - Yingping Zhuang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Ju Chu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Meijin Guo
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
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22
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Chromosome Engineering To Generate Plasmid-Free Phenylalanine- and Tyrosine-Overproducing Escherichia coli Strains That Can Be Applied in the Generation of Aromatic-Compound-Producing Bacteria. Appl Environ Microbiol 2020; 86:AEM.00525-20. [PMID: 32414798 DOI: 10.1128/aem.00525-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 05/11/2020] [Indexed: 12/25/2022] Open
Abstract
Many phenylalanine- and tyrosine-producing strains have used plasmid-based overexpression of pathway genes. The resulting strains achieved high titers and yields of phenylalanine and tyrosine. Chromosomally engineered, plasmid-free producers have shown lower titers and yields than plasmid-based strains, but the former are advantageous in terms of cultivation cost and public health/environmental risk. Therefore, we engineered here the Escherichia coli chromosome to create superior phenylalanine- and tyrosine-overproducing strains that did not depend on plasmid-based expression. Integration into the E. coli chromosome of two central metabolic pathway genes (ppsA and tktA) and eight shikimate pathway genes (aroA, aroB, aroC, aroD, aroE, aroGfbr , aroL, and pheAfbr ), controlled by the T7lac promoter, resulted in excellent titers and yields of phenylalanine; the superscript "fbr" indicates that the enzyme encoded by the gene was feedback resistant. The generated strain could be changed to be a superior tyrosine-producing strain by replacing pheAfbr with tyrAfbr A rational approach revealed that integration of seven genes (ppsA, tktA, aroA, aroB, aroC, aroGfbr , and pheAfbr ) was necessary as the minimum gene set for high-yield phenylalanine production in E. coli MG1655 (tyrR, adhE, ldhA, pykF, pflDC, and ascF deletant). The phenylalanine- and tyrosine-producing strains were further applied to generate phenyllactic acid-, 4-hydroxyphenyllactic acid-, tyramine-, and tyrosol-producing strains; yield of these aromatic compounds increased proportionally to the increase in phenylalanine and tyrosine yields.IMPORTANCE Plasmid-free strains for aromatic compound production are desired in the aspect of industrial application. However, the yields of phenylalanine and tyrosine have been considerably lower in plasmid-free strains than in plasmid-based strains. The significance of this research is that we succeeded in generating superior plasmid-free phenylalanine- and tyrosine-producing strains by engineering the E. coli chromosome, which was comparable to that in plasmid-based strains. The generated strains have a potential to generate superior strains for the production of aromatic compounds. Actually, we demonstrated that four kinds of aromatic compounds could be produced from glucose with high yields (e.g., 0.28 g tyrosol/g glucose).
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23
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Zhang J, Zhao Y, Cao Y, Yu Z, Wang G, Li Y, Ye X, Li C, Lin X, Song H. Synthetic sRNA-Based Engineering of Escherichia coli for Enhanced Production of Full-Length Immunoglobulin G. Biotechnol J 2020; 15:e1900363. [PMID: 32034883 DOI: 10.1002/biot.201900363] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 11/06/2019] [Indexed: 12/18/2022]
Abstract
Production of monoclonal antibodies (mAbs) receives considerable attention in the pharmaceutical industry. There has been an increasing interest in the expression of mAbs in Escherichia coli for analytical and therapeutic applications in recent years. Here, a modular synthetic biology approach is developed to rationally engineer E. coli by designing three functional modules to facilitate high-titer production of immunoglobulin G (IgG). First, a bicistronic expression system is constructed and the expression of the key genes in the pyruvate metabolism is tuned by the technologies of synthetic sRNA translational repression and gene overexpression, thus enhancing the cellular material and energy metabolism of E. coli for IgG biosynthesis (module 1). Second, to prevent the IgG biodegradation by proteases, the expression of a number of key proteases is identified and inhibited via synthetic sRNAs (module 2). Third, molecular chaperones are co-expressed to promote the secretion and folding of IgG (module 3). Synergistic integration of the three modules into the resulting recombinant E. coli results in a yield of the full-length IgG ≈150 mg L-1 in a 5L fed-batch bioreactor. The modular synthetic biology approach could be of general use in the production of recombinant mAbs.
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Affiliation(s)
- Jinhua Zhang
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE) , School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, P. R. China
| | - Yanshu Zhao
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE) , School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, P. R. China
| | - Yingxiu Cao
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE) , School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, P. R. China
| | - Zhenpeng Yu
- Yangzhou Lianao Biopharmaceutical Co. Ltd., and Yangzhou Aurisco Pharmaceutical Co. Ltd., Wanmei Road No. 5, Hanjiang Economic Development Zone, Yangzhou, Jiangsu, 225100, P. R. China
| | - Guoping Wang
- Yangzhou Lianao Biopharmaceutical Co. Ltd., and Yangzhou Aurisco Pharmaceutical Co. Ltd., Wanmei Road No. 5, Hanjiang Economic Development Zone, Yangzhou, Jiangsu, 225100, P. R. China
| | - Yiqun Li
- Yangzhou Lianao Biopharmaceutical Co. Ltd., and Yangzhou Aurisco Pharmaceutical Co. Ltd., Wanmei Road No. 5, Hanjiang Economic Development Zone, Yangzhou, Jiangsu, 225100, P. R. China
| | - Xiaoqiong Ye
- Yangzhou Lianao Biopharmaceutical Co. Ltd., and Yangzhou Aurisco Pharmaceutical Co. Ltd., Wanmei Road No. 5, Hanjiang Economic Development Zone, Yangzhou, Jiangsu, 225100, P. R. China
| | - Congfa Li
- College of Food Science and Technology, Hainan University, Haikou, 570228, P. R. China
| | - Xue Lin
- College of Food Science and Technology, Hainan University, Haikou, 570228, P. R. China
| | - Hao Song
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE) , School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, P. R. China
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Braga A, Faria N. Bioprocess Optimization for the Production of Aromatic Compounds With Metabolically Engineered Hosts: Recent Developments and Future Challenges. Front Bioeng Biotechnol 2020; 8:96. [PMID: 32154231 PMCID: PMC7044121 DOI: 10.3389/fbioe.2020.00096] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 02/03/2020] [Indexed: 12/18/2022] Open
Abstract
The most common route to produce aromatic chemicals - organic compounds containing at least one benzene ring in their structure - is chemical synthesis. These processes, usually starting from an extracted fossil oil molecule such as benzene, toluene, or xylene, are highly environmentally unfriendly due to the use of non-renewable raw materials, high energy consumption and the usual production of toxic by-products. An alternative way to produce aromatic compounds is extraction from plants. These extractions typically have a low yield and a high purification cost. This motivates the search for alternative platforms to produce aromatic compounds through low-cost and environmentally friendly processes. Microorganisms are able to synthesize aromatic amino acids through the shikimate pathway. The construction of microbial cell factories able to produce the desired molecule from renewable feedstock becomes a promising alternative. This review article focuses on the recent advances in microbial production of aromatic products, with a special emphasis on metabolic engineering strategies, as well as bioprocess optimization. The recent combination of these two techniques has resulted in the development of several alternative processes to produce phenylpropanoids, aromatic alcohols, phenolic aldehydes, and others. Chemical species that were unavailable for human consumption due to the high cost and/or high environmental impact of their production, have now become accessible.
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Affiliation(s)
- Adelaide Braga
- Centre of Biological Engineering, University of Minho, Braga, Portugal
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25
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Chen W, Chen R, Wang H, Li Y, Zhang Y, Li S. Tuning chromosomal gene expression in Escherichia coli by combining single-stranded oligonucleotides mediated recombination and kil counter selection system. J Biotechnol 2019; 307:63-68. [PMID: 31678458 DOI: 10.1016/j.jbiotec.2019.10.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 10/03/2019] [Accepted: 10/21/2019] [Indexed: 10/25/2022]
Abstract
Extensively modulating gene expression to achieve optimal flux is a critical step in metabolic engineering. Gene expression is usually modulated at the transcriptional level by controlling the strength of a promoter. However, this type of modulation is often hampered by its inability to fully sample the complete continuum of transcriptional control. In Escherichia coli, this limitation can be solved by constructing promoters with a wide range of strengths. In this study, a highly efficient method was developed to modulate a particular chromosomal gene of E. coli at a wide range of expression levels. This was achieved by combining highly efficient single-stranded oligonucleotide-mediated recombination and a stringent counter selection system kil. Using this strategy, a chromosomal library, with a range from 0.3% to 388% relative to the wild lac promoter, was easily obtained. The strength of our chromosomal promoter library was approximately 5-60 times wider in range than those of libraries reported before.
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Affiliation(s)
- Wei Chen
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, School of Biosciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou 510006, China.
| | - Ruyi Chen
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, School of Biosciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Hui Wang
- School of Biological Medicine, Beijing City University, Beijing, 10084, China
| | - Yujuan Li
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, School of Biosciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Yunyi Zhang
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, School of Biosciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Shanhu Li
- Beijing Institute of Biotechnology, Beijing 100850, China.
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26
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Liu Q, Yu T, Li X, Chen Y, Campbell K, Nielsen J, Chen Y. Rewiring carbon metabolism in yeast for high level production of aromatic chemicals. Nat Commun 2019; 10:4976. [PMID: 31672987 PMCID: PMC6823513 DOI: 10.1038/s41467-019-12961-5] [Citation(s) in RCA: 159] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Accepted: 10/11/2019] [Indexed: 12/22/2022] Open
Abstract
The production of bioactive plant compounds using microbial hosts is considered a safe, cost-competitive and scalable approach to their production. However, microbial production of some compounds like aromatic amino acid (AAA)-derived chemicals, remains an outstanding metabolic engineering challenge. Here we present the construction of a Saccharomyces cerevisiae platform strain able to produce high levels of p-coumaric acid, an AAA-derived precursor for many commercially valuable chemicals. This is achieved through engineering the AAA biosynthesis pathway, introducing a phosphoketalose-based pathway to divert glycolytic flux towards erythrose 4-phosphate formation, and optimizing carbon distribution between glycolysis and the AAA biosynthesis pathway by replacing the promoters of several important genes at key nodes between these two pathways. This results in a maximum p-coumaric acid titer of 12.5 g L−1 and a maximum yield on glucose of 154.9 mg g−1. Microbial production of aromatic amino acid (AAA)-derived chemicals remains an outstanding metabolic engineering challenge. Here, the authors engineer baker’s yeast for high levels p-coumaric acid production by rewiring the central carbon metabolism and channeling more flux to the AAA biosynthetic pathway.
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Affiliation(s)
- Quanli Liu
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE41296, Gothenburg, Sweden
| | - Tao Yu
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE41296, Gothenburg, Sweden
| | - Xiaowei Li
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE41296, Gothenburg, Sweden
| | - Yu Chen
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE41296, Gothenburg, Sweden
| | - Kate Campbell
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE41296, Gothenburg, Sweden
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK2800, Kongens Lyngby, Denmark
| | - Yun Chen
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE41296, Gothenburg, Sweden. .,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, SE41296, Gothenburg, Sweden.
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Liu X, Niu H, Li Q, Gu P. Metabolic engineering for the production of l-phenylalanine in Escherichia coli. 3 Biotech 2019; 9:85. [PMID: 30800596 DOI: 10.1007/s13205-019-1619-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 02/08/2019] [Indexed: 10/27/2022] Open
Abstract
As one of the three proteinogenic aromatic amino acids, l-phenylalanine is widely applied in the food, chemical and pharmaceutical industries, especially in production of the low-calorie sweetener aspartame. Microbial production of l-phenylalanine has become attractive as it possesses the advantages of environmental friendliness, low cost, and feedstock renewability. With the progress of metabolic engineering, systems biology and synthetic biology, production of l-phenylalanine from glucose in Escherichia coli with relatively high titer has been achieved by improving the intracellular levels of precursors, alleviating transcriptional repression and feedback inhibition of key enzymes, increasing the export of l-phenylalanine, engineering of global regulators, and overexpression of rate-limiting enzymes. In this review, successful metabolic engineering strategies for increasing l-phenylalanine accumulation from glucose in E. coli are described. In addition, perspectives for further improvement of production of l-phenylalanine are discussed.
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28
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Huccetogullari D, Luo ZW, Lee SY. Metabolic engineering of microorganisms for production of aromatic compounds. Microb Cell Fact 2019; 18:41. [PMID: 30808357 PMCID: PMC6390333 DOI: 10.1186/s12934-019-1090-4] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 02/19/2019] [Indexed: 01/09/2023] Open
Abstract
Metabolic engineering has been enabling development of high performance microbial strains for the efficient production of natural and non-natural compounds from renewable non-food biomass. Even though microbial production of various chemicals has successfully been conducted and commercialized, there are still numerous chemicals and materials that await their efficient bio-based production. Aromatic chemicals, which are typically derived from benzene, toluene and xylene in petroleum industry, have been used in large amounts in various industries. Over the last three decades, many metabolically engineered microorganisms have been developed for the bio-based production of aromatic chemicals, many of which are derived from aromatic amino acid pathways. This review highlights the latest metabolic engineering strategies and tools applied to the biosynthesis of aromatic chemicals, many derived from shikimate and aromatic amino acids, including L-phenylalanine, L-tyrosine and L-tryptophan. It is expected that more and more engineered microorganisms capable of efficiently producing aromatic chemicals will be developed toward their industrial-scale production from renewable biomass.
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Affiliation(s)
- Damla Huccetogullari
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program) and Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
| | - Zi Wei Luo
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program) and Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea
| | - Sang Yup Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program) and Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
- Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, KAIST, Daejeon, 34141, Republic of Korea.
- BioProcess Engineering Research Center and Bioinformatics Research Center, KAIST, Daejeon, 34141, Republic of Korea.
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Metabolic engineering for improving l-tryptophan production in Escherichia coli. ACTA ACUST UNITED AC 2019; 46:55-65. [DOI: 10.1007/s10295-018-2106-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 11/03/2018] [Indexed: 11/26/2022]
Abstract
Abstract
l-Tryptophan is an important aromatic amino acid that is used widely in the food, chemical, and pharmaceutical industries. Compared with the traditional synthetic methods, production of l-tryptophan by microbes is environmentally friendly and has low production costs, and feed stocks are renewable. With the development of metabolic engineering, highly efficient production of l-tryptophan in Escherichia coli has been achieved by eliminating negative regulation factors, improving the intracellular level of precursors, engineering of transport systems and overexpression of rate-limiting enzymes. However, challenges remain for l-tryptophan biosynthesis to be cost-competitive. In this review, successful and applicable strategies derived from metabolic engineering for increasing l-tryptophan accumulation in E. coli are summarized. In addition, perspectives for further efficient production of l-tryptophan are discussed.
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30
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Escherichia coli as a host for metabolic engineering. Metab Eng 2018; 50:16-46. [DOI: 10.1016/j.ymben.2018.04.008] [Citation(s) in RCA: 181] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 04/11/2018] [Accepted: 04/12/2018] [Indexed: 12/21/2022]
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31
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Rational design and analysis of an Escherichia coli strain for high-efficiency tryptophan production. ACTA ACUST UNITED AC 2018; 45:357-367. [DOI: 10.1007/s10295-018-2020-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 02/04/2018] [Indexed: 01/24/2023]
Abstract
Abstract
l-tryptophan (l-trp) is a precursor of various bioactive components and has great pharmaceutical interest. However, due to the requirement of several precursors and complex regulation of the pathways involved, the development of an efficient l-trp production strain is challenging. In this study, Escherichia coli (E. coli) strain KW001 was designed to overexpress the l-trp operator sequences (trpEDCBA) and 3-deoxy-D-arabinoheptulosonate-7-phosphate synthase (aroGfbr). To further improve the production of l-trp, pyruvate kinase (pykF) and the phosphotransferase system HPr (ptsH) were deleted after inactivation of repression (trpR) and attenuation (attenuator) to produce strain KW006. To overcome the relatively slow growth and to increase the transport rate of glucose, strain KW018 was generated by combinatorial regulation of glucokinase (galP) and galactose permease (glk) expression. To reduce the production of acetic acid, strain KW023 was created by repressive regulation of phosphate acetyltransferase (pta) expression. In conclusion, strain KW023 efficiently produced 39.7 g/L of l-trp with a conversion rate of 16.7% and a productivity of 1.6 g/L/h in a 5 L fed-batch fermentation system.
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Averesch NJH, Krömer JO. Metabolic Engineering of the Shikimate Pathway for Production of Aromatics and Derived Compounds-Present and Future Strain Construction Strategies. Front Bioeng Biotechnol 2018; 6:32. [PMID: 29632862 PMCID: PMC5879953 DOI: 10.3389/fbioe.2018.00032] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 03/12/2018] [Indexed: 11/25/2022] Open
Abstract
The aromatic nature of shikimate pathway intermediates gives rise to a wealth of potential bio-replacements for commonly fossil fuel-derived aromatics, as well as naturally produced secondary metabolites. Through metabolic engineering, the abundance of certain intermediates may be increased, while draining flux from other branches off the pathway. Often targets for genetic engineering lie beyond the shikimate pathway, altering flux deep in central metabolism. This has been extensively used to develop microbial production systems for a variety of compounds valuable in chemical industry, including aromatic and non-aromatic acids like muconic acid, para-hydroxybenzoic acid, and para-coumaric acid, as well as aminobenzoic acids and aromatic α-amino acids. Further, many natural products and secondary metabolites that are valuable in food- and pharma-industry are formed outgoing from shikimate pathway intermediates. (Re)construction of such routes has been shown by de novo production of resveratrol, reticuline, opioids, and vanillin. In this review, strain construction strategies are compared across organisms and put into perspective with requirements by industry for commercial viability. Focus is put on enhancing flux to and through shikimate pathway, and engineering strategies are assessed in order to provide a guideline for future optimizations.
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Affiliation(s)
- Nils J H Averesch
- Universities Space Research Association at NASA Ames Research Center, Moffett Field, CA, United States
| | - Jens O Krömer
- Department of Solar Materials, Helmholtz Centre for Environmental Research, Leipzig, Germany
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Golubeva LI, Shupletsov MS, Mashko SV. Metabolic Flux Analysis using 13C Isotopes: III. Significance for Systems Biology and Metabolic Engineering. APPL BIOCHEM MICRO+ 2018. [DOI: 10.1134/s0003683817090058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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34
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Hsu TM, Welner DH, Russ ZN, Cervantes B, Prathuri RL, Adams PD, Dueber JE. Employing a biochemical protecting group for a sustainable indigo dyeing strategy. Nat Chem Biol 2018; 14:256-261. [PMID: 29309053 PMCID: PMC5866135 DOI: 10.1038/nchembio.2552] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 11/14/2017] [Indexed: 11/09/2022]
Abstract
Indigo is an ancient dye uniquely capable of producing the signature tones in blue denim; however, the dyeing process requires chemical steps that are environmentally damaging. We describe a sustainable dyeing strategy that not only circumvents the use of toxic reagents for indigo chemical synthesis but also removes the need for a reducing agent for dye solubilization. This strategy utilizes a glucose moiety as a biochemical protecting group to stabilize the reactive indigo precursor indoxyl to form indican, preventing spontaneous oxidation to crystalline indigo during microbial fermentation. Application of a β-glucosidase removes the protecting group from indican, resulting in indigo crystal formation in the cotton fibers. We identified the gene coding for the glucosyltransferase PtUGT1 from the indigo plant Polygonum tinctorium and solved the structure of PtUGT1. Heterologous expression of PtUGT1 in Escherichia coli supported high indican conversion, and biosynthesized indican was used to dye cotton swatches and a garment.
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Affiliation(s)
- Tammy M Hsu
- Department of Bioengineering, University of California, Berkeley, Berkeley, California, USA
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley, Berkeley, California, USA
| | - Ditte H Welner
- Joint BioEnergy Institute, Emeryville, California, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratories, Berkeley, California, USA
| | - Zachary N Russ
- Department of Bioengineering, University of California, Berkeley, Berkeley, California, USA
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley, Berkeley, California, USA
| | - Bernardo Cervantes
- Department of Bioengineering, University of California, Berkeley, Berkeley, California, USA
| | - Ramya L Prathuri
- Department of Bioengineering, University of California, Berkeley, Berkeley, California, USA
| | - Paul D Adams
- Department of Bioengineering, University of California, Berkeley, Berkeley, California, USA
- Joint BioEnergy Institute, Emeryville, California, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratories, Berkeley, California, USA
| | - John E Dueber
- Department of Bioengineering, University of California, Berkeley, Berkeley, California, USA
- Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
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35
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Metabolic engineering of Escherichia coli for the production of indirubin from glucose. J Biotechnol 2018; 267:19-28. [DOI: 10.1016/j.jbiotec.2017.12.026] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 12/22/2017] [Accepted: 12/31/2017] [Indexed: 11/19/2022]
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36
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Liu C, Men X, Chen H, Li M, Ding Z, Chen G, Wang F, Liu H, Wang Q, Zhu Y, Zhang H, Xian M. A systematic optimization of styrene biosynthesis in Escherichia coli BL21(DE3). BIOTECHNOLOGY FOR BIOFUELS 2018; 11:14. [PMID: 29416559 PMCID: PMC5784704 DOI: 10.1186/s13068-018-1017-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Accepted: 01/10/2018] [Indexed: 05/28/2023]
Abstract
BACKGROUND Styrene is a versatile commodity petrochemical used as a monomer building-block for the synthesis of many useful polymers. Although achievements have been made on styrene biosynthesis in microorganisms, several bottleneck problems limit factors for further improvement in styrene production. RESULTS A two-step styrene biosynthesis pathway was developed and introduced into Escherichia coli BL21(DE3). Systematic optimization of styrene biosynthesis, such as enzyme screening, codon and plasmid optimization, metabolic flow balance, and in situ fermentation was performed. Candidate isoenzymes of the rate-limiting enzyme phenylalanine ammonia lyase (PAL) were screened from Arabidopsis thaliana (AtPAL2), Fagopyrum tataricum (FtPAL), Petroselinum crispum (PcPAL), and Artemisia annua (AaPAL). After codon optimization, AtPAL2 was found to be the most effective one, and the engineered strain was able to produce 55 mg/L styrene. Subsequently, plasmid optimization was performed, which improved styrene production to 103 mg/L. In addition, two upstream shikimate pathway genes, aroF and pheA, were overexpressed in the engineered strain, which resulted in styrene production of 210 mg/L. Subsequently, combined overexpression of tktA and ppsA increased styrene production to 275 mg/L. Finally, in situ product removal was used to ease the burden of end-product toxicity. By using isopropyl myristate as a solvent, styrene production reached a final titer of 350 mg/L after 48 h of shake-flask fermentation, representing a 636% improvement, which compared with that achieved in the original strain. CONCLUSIONS This present study achieved the highest titer of de novo production of styrene in E. coli at shake-flask fermentation level. These results obtained provided new insights for the development of microbial production of styrene in a sustainable and environment friendly manner.
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Affiliation(s)
- Changqing Liu
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiao Men
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hailin Chen
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Meijie Li
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zhaorui Ding
- School of Biological Science, Jining Medical University, Jining, 272067 People’s Republic of China
| | - Guoqiang Chen
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Fan Wang
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Haobao Liu
- Key Laboratory for Tobacco, Gene Resources’ Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101 People’s Republic of China
| | - Qian Wang
- Key Laboratory for Tobacco, Gene Resources’ Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101 People’s Republic of China
| | - Youshuang Zhu
- School of Biological Science, Jining Medical University, Jining, 272067 People’s Republic of China
| | - Haibo Zhang
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Mo Xian
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
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Liu C, Zhang K, Cao W, Zhang G, Chen G, Yang H, Wang Q, Liu H, Xian M, Zhang H. Genome mining of 2-phenylethanol biosynthetic genes from Enterobacter sp. CGMCC 5087 and heterologous overproduction in Escherichia coli. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:305. [PMID: 30455734 PMCID: PMC6223000 DOI: 10.1186/s13068-018-1297-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 10/22/2018] [Indexed: 05/22/2023]
Abstract
BACKGROUND 2-Phenylethanol (2-PE) is a higher aromatic alcohol that is widely used in the perfumery, cosmetics, and food industries and is also a potentially valuable next-generation biofuel. In our previous study, a new strain Enterobacter sp. CGMCC 5087 was isolated to produce 2-PE from glucose through the phenylpyruvate pathway. RESULTS In this study, candidate genes for 2-PE biosynthesis were identified from Enterobacter sp. CGMCC 5087 by draft whole-genome sequence, metabolic engineering, and shake flask fermentation. Subsequently, the identified genes encoding the 2-keto acid decarboxylase (Kdc) and alcohol dehydrogenase (Adh) enzymes from Enterobacter sp. CGMCC 5087 were introduced into E. coli BL21(DE3) to construct a high-efficiency microbial cell factory for 2-PE production using the prokaryotic phenylpyruvate pathway. The enzymes Kdc4427 and Adh4428 from Enterobacter sp. CGMCC 5087 showed higher performances than did the corresponding enzymes ARO10 and ADH2 from Saccharomyces cerevisiae, respectively. The E. coli cell factory was further improved by overexpressing two upstream shikimate pathway genes, aroF/aroG/aroH and pheA, to enhance the metabolic flux of the phenylpyruvate pathway, which resulted in 2-PE production of 260 mg/L. The combined overexpression of tktA and ppsA increased the precursor supply of erythrose-4-phosphate and phosphoenolpyruvate, which resulted in 2-PE production of 320 mg/L, with a productivity of 13.3 mg/L/h. CONCLUSIONS The present study achieved the highest titer of de novo 2-PE production of in a recombinant E. coli system. This study describes a new, efficient 2-PE producer that lays foundation for the industrial-scale production of 2-PE and its derivatives in the future.
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Affiliation(s)
- Changqing Liu
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Kai Zhang
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Wenyan Cao
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ge Zhang
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
- Key Laboratory for Tobacco Gene Resources’ Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101 People’s Republic of China
| | - Guoqiang Chen
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
- Key Laboratory for Tobacco Gene Resources’ Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101 People’s Republic of China
| | - Haiyan Yang
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Qian Wang
- Key Laboratory for Tobacco Gene Resources’ Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101 People’s Republic of China
| | - Haobao Liu
- Key Laboratory for Tobacco Gene Resources’ Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101 People’s Republic of China
| | - Mo Xian
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Haibo Zhang
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
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Yao R, Pan K, Peng H, Feng L, Hu H, Zhang X. Engineering and systems-level analysis of Pseudomonas chlororaphis for production of phenazine-1-carboxamide using glycerol as the cost-effective carbon source. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:130. [PMID: 29755589 PMCID: PMC5934903 DOI: 10.1186/s13068-018-1123-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 04/19/2018] [Indexed: 05/21/2023]
Abstract
BACKGROUND Glycerol, an inevitable byproduct of biodiesel, has become an attractive feedstock for the production of value-added chemicals due to its availability and low price. Pseudomonas chlororaphis HT66 can use glycerol to synthesize phenazine-1-carboxamide (PCN), a phenazine derivative, which is strongly antagonistic to fungal phytopathogens. A systematic understanding of underlying mechanisms for the PCN overproduction will be important for the further improvement and industrialization. RESULTS We constructed a PCN-overproducing strain (HT66LSP) through knocking out three negative regulatory genes, lon, parS, and prsA in HT66. The strain HT66LSP produced 4.10 g/L of PCN with a yield of 0.23 (g/g) from glycerol, which was of the highest titer and the yield obtained among PCN-producing strains. We studied gene expression, metabolomics, and dynamic 13C tracer in HT66 and HT66LSP. In response to the phenotype changes, the transcript levels of phz biosynthetic genes, which are responsible for PCN biosynthesis, were all upregulated in HT66LSP. Central carbon was rerouted to the shikimate pathway, which was shown by the modulation of specific genes involved in the lower glycolysis, the TCA cycle, and the shikimate pathway, as well as changes in abundances of intracellular metabolites and flux distribution to increase the precursor availability for PCN biosynthesis. Moreover, dynamic 13C-labeling experiments revealed that the presence of metabolite channeling of 3-phosphoglyceric acid to phosphoenolpyruvate and shikimate to trans-2,3-dihydro-3-hydroxyanthranilic acid in HT66LSP could enable high-yielding synthesis of PCN. CONCLUSIONS The integrated analysis of gene expression, metabolomics, and dynamic 13C tracer enabled us to gain a more in-depth insight into complex mechanisms for the PCN overproduction. This study provides important basis for further engineering P. chlororaphis for high PCN production and efficient glycerol conversion.
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Affiliation(s)
- Ruilian Yao
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240 China
| | - Keli Pan
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240 China
| | - Huasong Peng
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240 China
| | - Lei Feng
- Instrumental Analysis Center, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240 China
| | - Hongbo Hu
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240 China
| | - Xuehong Zhang
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240 China
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Liu L, Chen S, Wu J. Phosphoenolpyruvate:glucose phosphotransferase system modification increases the conversion rate during L-tryptophan production in Escherichia coli. J Ind Microbiol Biotechnol 2017; 44:1385-1395. [PMID: 28726163 DOI: 10.1007/s10295-017-1959-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 06/09/2017] [Indexed: 11/27/2022]
Abstract
Escherichia coli FB-04(pta1), a recombinant L-tryptophan production strain, was constructed in our laboratory. However, the conversion rate (L-tryptophan yield per glucose) of this strain is somewhat low. In this study, additional genes have been deleted in an effort to increase the conversion rate of E. coli FB-04(pta1). Initially, the pykF gene, which encodes pyruvate kinase I (PYKI), was inactivated to increase the accumulation of phosphoenolpyruvate, a key L-tryptophan precursor. The resulting strain, E. coli FB-04(pta1)ΔpykF, showed a slightly higher L-tryptophan yield and a higher conversion rate in fermentation processes. To further improve the conversion rate, the phosphoenolpyruvate:glucose phosphotransferase system (PTS) was disrupted by deleting the ptsH gene, which encodes the phosphocarrier protein (HPr). The levels of biomass, L-tryptophan yield, and conversion rate of this strain, E. coli FB-04(pta1)ΔpykF/ptsH, were especially low during fed-batch fermentation process, even though it achieved a significant increase in conversion rate during shake-flask fermentation. To resolve this issue, four HPr mutations (N12S, N12A, S46A, and S46N) were introduced into the genomic background of E. coli FB-04(pta1)ΔpykF/ptsH, respectively. Among them, the strain harboring the N12S mutation (E. coli FB-04(pta1)ΔpykF-ptsHN12S) showed a prominently increased conversion rate of 0.178 g g-1 during fed-batch fermentation; an increase of 38.0% compared with parent strain E. coli FB-04(pta1). Thus, mutation of the genomic of ptsH gene provided an alternative method to weaken the PTS and improve the efficiency of carbon source utilization.
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Affiliation(s)
- Lina Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,School of Biotechnology and Key Laboratory of Industrial Biotechnology Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| | - Sheng Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,School of Biotechnology and Key Laboratory of Industrial Biotechnology Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| | - Jing Wu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China. .,School of Biotechnology and Key Laboratory of Industrial Biotechnology Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.
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40
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Panichkin VB, Livshits VA, Biryukova IV, Mashko SV. Metabolic engineering of Escherichia coli for L-tryptophan production. APPL BIOCHEM MICRO+ 2017. [DOI: 10.1134/s0003683816090052] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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41
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Gao M, Cao M, Suástegui M, Walker J, Rodriguez Quiroz N, Wu Y, Tribby D, Okerlund A, Stanley L, Shanks JV, Shao Z. Innovating a Nonconventional Yeast Platform for Producing Shikimate as the Building Block of High-Value Aromatics. ACS Synth Biol 2017; 6:29-38. [PMID: 27600996 DOI: 10.1021/acssynbio.6b00132] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The shikimate pathway serves an essential role in many organisms. Not only are the three aromatic amino acids synthesized through this pathway, but many secondary metabolites also derive from it. Decades of effort have been invested into engineering Saccharomyces cerevisiae to produce shikimate and its derivatives. In addition to the ability to express cytochrome P450, S. cerevisiae is generally recognized as safe for producing compounds with nutraceutical and pharmaceutical applications. However, the intrinsically complicated regulations involved in central metabolism and the low precursor availability in S. cerevisiae has limited production levels. Here we report the development of a new platform based on Scheffersomyces stipitis, whose superior xylose utilization efficiency makes it particularly suited to produce the shikimate group of compounds. Shikimate was produced at 3.11 g/L, representing the highest level among shikimate pathway products in yeasts. Our work represents a new exploration toward expanding the current collection of microbial factories.
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Affiliation(s)
- Meirong Gao
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Mingfeng Cao
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Miguel Suástegui
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - James Walker
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Natalia Rodriguez Quiroz
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Yutong Wu
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Dana Tribby
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Adam Okerlund
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Levi Stanley
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Jacqueline V. Shanks
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Zengyi Shao
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
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42
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Engineering the shikimate pathway for biosynthesis of molecules with pharmaceutical activities in E. coli. Curr Opin Biotechnol 2016; 42:1-6. [DOI: 10.1016/j.copbio.2016.01.016] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 01/20/2016] [Accepted: 01/30/2016] [Indexed: 11/23/2022]
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43
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44
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Kogure T, Kubota T, Suda M, Hiraga K, Inui M. Metabolic engineering of Corynebacterium glutamicum for shikimate overproduction by growth-arrested cell reaction. Metab Eng 2016; 38:204-216. [DOI: 10.1016/j.ymben.2016.08.005] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 08/16/2016] [Accepted: 08/18/2016] [Indexed: 11/30/2022]
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Mejía-Caballero A, de Anda R, Hernández-Chávez G, Rogg S, Martinez A, Bolívar F, Castaño VM, Gosset G. Biosynthesis of catechol melanin from glycerol employing metabolically engineered Escherichia coli. Microb Cell Fact 2016; 15:161. [PMID: 27659593 PMCID: PMC5034560 DOI: 10.1186/s12934-016-0561-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/14/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Melanins comprise a chemically-diverse group of polymeric pigments whose function is related to protection against physical and chemical stress factors. These polymers have current and potential applications in the chemical, medical, electronics and materials industries. The biotechnological production of melanins offers the possibility of obtaining these pigments in pure form and relatively low cost. In this study, Escherichia coli strains were engineered to evaluate the production of melanin from supplemented catechol or from glycerol-derived catechol produced by an Escherichia coli strain generated by metabolic engineering. RESULTS It was determined that an improved mutant version of the tyrosinase from Rhizobium etli (MutmelA), could employ catechol as a substrate to generate melanin. Strain E. coli W3110 expressing MutmelA was grown in bioreactor batch cultures with catechol supplemented in the medium. Under these conditions, 0.29 g/L of catechol melanin were produced. A strain with the capacity to synthesize catechol melanin from a simple carbon source was generated by integrating the gene MutmelA into the chromosome of E. coli W3110 trpD9923, that has been modified to produce catechol by the expression of genes encoding a feedback inhibition resistant version of 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase, transketolase and anthranilate 1,2-dioxygenase from Pseudomonas aeruginosa PAO1. In batch cultures with this strain employing complex medium with 40 g/L glycerol as a carbon source, 1.21 g/L of catechol melanin were produced. The melanin was analysed by employing Fourier transform infrared spectroscopy, revealing the expected characteristics for a catechol-derived polymer. CONCLUSIONS This constitutes the first report of an engineered E. coli strain and a fermentation process for producing a catechol melanin from a simple carbon source (glycerol) at gram level, opening the possibility of generating a large quantity of this polymer for its detailed characterization and the development of novel applications.
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Affiliation(s)
- Alejandra Mejía-Caballero
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, MOR, CP 62271, Mexico
| | - Ramón de Anda
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, MOR, CP 62271, Mexico
| | - Georgina Hernández-Chávez
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, MOR, CP 62271, Mexico
| | - Simone Rogg
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Santiago de Querétaro, Mexico
| | - Alfredo Martinez
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, MOR, CP 62271, Mexico
| | - Francisco Bolívar
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, MOR, CP 62271, Mexico
| | - Victor M Castaño
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Santiago de Querétaro, Mexico
| | - Guillermo Gosset
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca, MOR, CP 62271, Mexico.
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46
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Genome engineering Escherichia coli for L-DOPA overproduction from glucose. Sci Rep 2016; 6:30080. [PMID: 27417146 PMCID: PMC4945936 DOI: 10.1038/srep30080] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 06/29/2016] [Indexed: 12/26/2022] Open
Abstract
Genome engineering has become a powerful tool for creating useful strains in research and industry. In this study, we applied singleplex and multiplex genome engineering approaches to construct an E. coli strain for the production of L-DOPA from glucose. We first used the singleplex genome engineering approach to create an L-DOPA-producing strain, E. coli DOPA-1, by deleting transcriptional regulators (tyrosine repressor tyrR and carbon storage regulator A csrA), altering glucose transport from the phosphotransferase system (PTS) to ATP-dependent uptake and the phosphorylation system overexpressing galactose permease gene (galP) and glucokinase gene (glk), knocking out glucose-6-phosphate dehydrogenase gene (zwf) and prephenate dehydratase and its leader peptide genes (pheLA) and integrating the fusion protein chimera of the downstream pathway of chorismate. Then, multiplex automated genome engineering (MAGE) based on 23 targets was used to further improve L-DOPA production. The resulting strain, E. coli DOPA-30N, produced 8.67 g/L of L-DOPA in 60 h in a 5 L fed-batch fermentation. This titer is the highest achieved in metabolically engineered E. coli having PHAH activity from glucose.
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Suástegui M, Guo W, Feng X, Shao Z. Investigating strain dependency in the production of aromatic compounds in
Saccharomyces cerevisiae. Biotechnol Bioeng 2016; 113:2676-2685. [DOI: 10.1002/bit.26037] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 05/16/2016] [Accepted: 06/13/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Miguel Suástegui
- Department of Chemical and Biological EngineeringIowa State UniversityAmesIowa
- NSF Engineering Research Center for Biorenewable Chemicals (CBiRC)AmesIowa
| | - Weihua Guo
- Department of Biological Systems EngineeringVirginia Polytechnic Institute and State UniversityBlacksburgVirginia
| | - Xueyang Feng
- Department of Biological Systems EngineeringVirginia Polytechnic Institute and State UniversityBlacksburgVirginia
| | - Zengyi Shao
- Department of Chemical and Biological EngineeringIowa State UniversityAmesIowa
- NSF Engineering Research Center for Biorenewable Chemicals (CBiRC)AmesIowa
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48
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Ghosh S, Mohan U, Banerjee UC. Studies on the production of shikimic acid using the aroK knockout strain of Bacillus megaterium. World J Microbiol Biotechnol 2016; 32:127. [DOI: 10.1007/s11274-016-2092-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 05/24/2016] [Indexed: 11/29/2022]
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49
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Modulating the direction of carbon flow in Escherichia coli to improve l-tryptophan production by inactivating the global regulator FruR. J Biotechnol 2016; 231:141-148. [PMID: 27297546 DOI: 10.1016/j.jbiotec.2016.06.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/30/2016] [Accepted: 06/09/2016] [Indexed: 11/22/2022]
Abstract
The fructose repressor (FruR) affects carbon flux through the central metabolic pathways of Escherichia coli. In this study, l-tryptophan production in Escherichia coli FB-04 was improved by knocking out the fruR gene, thereby inactivating FruR. This fruR knockout strain, E. coli FB-04(ΔfruR), not only exhibited higher growth efficiency, it also showed substantially improved l-tryptophan production. l-tryptophan production by E. coli FB-04(ΔfruR) and l-tryptophan yield per glucose were increased by 62.5% and 52.4%, respectively, compared with the parent E. coli FB-04. Metabolomics analysis showed that the fruR knockout significantly enhances metabolic flow through glycolysis, the pentose phosphate pathway and the TCA cycle, increasing levels of critical precursors and substrates for l-tryptophan biosynthesis. These results indicate that fruR deletion should enhance l-tryptophan production and improve the efficiency of carbon source utilization independent of genetic background.
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50
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Jang S, Lee B, Jeong HH, Jin SH, Jang S, Kim SG, Jung GY, Lee CS. On-chip analysis, indexing and screening for chemical producing bacteria in a microfluidic static droplet array. LAB ON A CHIP 2016; 16:1909-16. [PMID: 27102263 DOI: 10.1039/c6lc00118a] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Economic production of chemicals from microbes necessitates development of high-producing strains and an efficient screening technology is crucial to maximize the effect of the most popular strain improvement method, the combinatorial approach. However, high-throughput screening has been limited for assessment of diverse intracellular metabolites at the single-cell level. Herein, we established a screening platform that couples a microfluidic static droplet array (SDA) and an artificial riboswitch to analyse intracellular metabolite concentration from single microbial cells. Using this system, we entrapped single Escherichia coli cells in SDA to measure intracellular l-tryptophan concentrations. It was validated that intracellular l-tryptophan concentration can be evaluated by the fluorescence from the riboswitch. Moreover, high-producing strains were successfully screened from a mutagenized library, exhibiting up to 145% productivity compared to its parental strain. This platform will be widely applicable to strain improvement for diverse metabolites by developing new artificial riboswitches.
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Affiliation(s)
- Sungho Jang
- Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 790-784, Korea.
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