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Xue B, Liu Y, Yang C, Liu H, Yuan Q, Wang S, Su H. Co-Cultivated Enzyme Constraint Metabolic Network Model for Rational Guidance in Constructing Synthetic Consortia to Achieve Optimal Pathway Allocation Prediction. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2306662. [PMID: 38093511 PMCID: PMC10916542 DOI: 10.1002/advs.202306662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/23/2023] [Indexed: 03/07/2024]
Abstract
Synthetic consortia have emerged as a promising biosynthetic platform that offers new opportunities for biosynthesis. Genome-scale metabolic network models (GEMs) with complex constraints are extensively utilized to guide the synthesis in monocultures. However, few methods are currently available to guide the rational construction of synthetic consortia for predicting the optimal allocation strategy of synthetic pathways aimed at enhancing product synthesis. A standardized method to construct the co-cultivated Enzyme Constraint metabolic network model (CulECpy) is proposed, which integrates enzyme constraints and modular interaction scale constraints based on the research concept of "independent + global". This method is applied to construct several synthetic consortia models, which encompassed different target products, strains, synthetic pathways, and compositional structures. Analyzing the model, the optimal pathway allocation and initial inoculum ratio that enhance the synthesis of target products by synthetic consortia are predicted and verified. When comparing with the constructed co-culture synthesis system, the normalized root mean square error of all optimal theoretical yield simulations is found to be less than or equal to 0.25. The analyses and verifications demonstrate that the method CulECpy can guide the rational construction of synthetic consortia systems to facilitate biochemical synthesis.
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Affiliation(s)
- Boyuan Xue
- Beijing Key Laboratory of Bioprocessand Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing100029P. R. China
| | - Yu Liu
- Beijing Key Laboratory of Bioprocessand Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing100029P. R. China
| | - Chen Yang
- Beijing Key Laboratory of Bioprocessand Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing100029P. R. China
| | - Hao Liu
- Beijing Key Laboratory of Bioprocessand Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing100029P. R. China
| | - Qianqian Yuan
- Biodesign CenterKey Laboratory of Engineering Biology for Low‐carbon ManufacturingTianjin Institute of Industrial BiotechnologyChinese Academy of SciencesTianjin300308P. R. China
| | - Shaojie Wang
- Beijing Key Laboratory of Bioprocessand Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing100029P. R. China
| | - Haijia Su
- Beijing Key Laboratory of Bioprocessand Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing100029P. R. China
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Zhao G, Zhao S, Hagner Nielsen L, Zhou F, Gu L, Tilahun Tadesse B, Solem C. Transforming acid whey into a resource by selective removal of lactic acid and galactose using optimized food-grade microorganisms. BIORESOURCE TECHNOLOGY 2023; 387:129594. [PMID: 37532060 DOI: 10.1016/j.biortech.2023.129594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 07/26/2023] [Accepted: 07/30/2023] [Indexed: 08/04/2023]
Abstract
The presence of lactic acid and galactose makes spray drying of acid whey (AW) a significant challenge for the dairy industry. In this study, a novel approach is explored to remove these compounds, utilizing food-grade microorganisms. For removing lactic acid, Corynebacterium glutamicum was selected, which has an inherent ability to metabolize lactic acid but does so slowly. To accelerate lactic acid metabolism, a mutant strain G6006 was isolated through adaptive laboratory evolution, which metabolized all lactic acid from AW two times faster than its parent strain. To eliminate galactose, a lactose-negative mutant of Lactococcus lactis that cannot produce lactate was generated. This strain was then co-cultured with G6006 to maximize the removal of both lactic acid and galactose. The microbially "filtered" AW could readily be spray dried into a stable lactose powder. This study highlights the potential of utilizing food-grade microorganisms to process AW, which currently constitutes a global challenge.
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Affiliation(s)
- Ge Zhao
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Shuangqing Zhao
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Line Hagner Nielsen
- DTU Health Tech, Department of Health Technology, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Fa Zhou
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Liuyan Gu
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Belay Tilahun Tadesse
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Christian Solem
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
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Niu J, Mao Z, Mao Y, Wu K, Shi Z, Yuan Q, Cai J, Ma H. Construction and Analysis of an Enzyme-Constrained Metabolic Model of Corynebacterium glutamicum. Biomolecules 2022; 12:1499. [PMID: 36291707 PMCID: PMC9599660 DOI: 10.3390/biom12101499] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 10/08/2022] [Accepted: 10/14/2022] [Indexed: 05/25/2024] Open
Abstract
The genome-scale metabolic model (GEM) is a powerful tool for interpreting and predicting cellular phenotypes under various environmental and genetic perturbations. However, GEM only considers stoichiometric constraints, and the simulated growth and product yield values will show a monotonic linear increase with increasing substrate uptake rate, which deviates from the experimentally measured values. Recently, the integration of enzymatic constraints into stoichiometry-based GEMs was proven to be effective in making novel discoveries and predicting new engineering targets. Here, we present the first genome-scale enzyme-constrained model (ecCGL1) for Corynebacterium glutamicum reconstructed by integrating enzyme kinetic data from various sources using a ECMpy workflow based on the high-quality GEM of C. glutamicum (obtained by modifying the iCW773 model). The enzyme-constrained model improved the prediction of phenotypes and simulated overflow metabolism, while also recapitulating the trade-off between biomass yield and enzyme usage efficiency. Finally, we used the ecCGL1 to identify several gene modification targets for l-lysine production, most of which agree with previously reported genes. This study shows that incorporating enzyme kinetic information into the GEM enhances the cellular phenotypes prediction of C. glutamicum, which can help identify key enzymes and thus provide reliable guidance for metabolic engineering.
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Affiliation(s)
- Jinhui Niu
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Zhitao Mao
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Yufeng Mao
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Ke Wu
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Zhenkun Shi
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Qianqian Yuan
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Jingyi Cai
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Hongwu Ma
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230026, China
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
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Refactoring transcription factors for metabolic engineering. Biotechnol Adv 2022; 57:107935. [PMID: 35271945 DOI: 10.1016/j.biotechadv.2022.107935] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 02/04/2022] [Accepted: 03/03/2022] [Indexed: 12/19/2022]
Abstract
Due to the ability to regulate target metabolic pathways globally and dynamically, metabolic regulation systems composed of transcription factors have been widely used in metabolic engineering and synthetic biology. This review introduced the categories, action principles, prediction strategies, and related databases of transcription factors. Then, the application of global transcription machinery engineering technology and the transcription factor-based biosensors and quorum sensing systems are overviewed. In addition, strategies for optimizing the transcriptional regulatory tools' performance by refactoring transcription factors are summarized. Finally, the current limitations and prospects of constructing various regulatory tools based on transcription factors are discussed. This review will provide theoretical guidance for the rational design and construction of transcription factor-based metabolic regulation systems.
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Wiechert W, Nöh K. Quantitative Metabolic Flux Analysis Based on Isotope Labeling. Metab Eng 2021. [DOI: 10.1002/9783527823468.ch3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Prell C, Busche T, Rückert C, Nolte L, Brandenbusch C, Wendisch VF. Adaptive laboratory evolution accelerated glutarate production by Corynebacterium glutamicum. Microb Cell Fact 2021; 20:97. [PMID: 33971881 PMCID: PMC8112011 DOI: 10.1186/s12934-021-01586-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 04/26/2021] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND The demand for biobased polymers is increasing steadily worldwide. Microbial hosts for production of their monomeric precursors such as glutarate are developed. To meet the market demand, production hosts have to be improved constantly with respect to product titers and yields, but also shortening bioprocess duration is important. RESULTS In this study, adaptive laboratory evolution was used to improve a C. glutamicum strain engineered for production of the C5-dicarboxylic acid glutarate by flux enforcement. Deletion of the L-glutamic acid dehydrogenase gene gdh coupled growth to glutarate production since two transaminases in the glutarate pathway are crucial for nitrogen assimilation. The hypothesis that strains selected for faster glutarate-coupled growth by adaptive laboratory evolution show improved glutarate production was tested. A serial dilution growth experiment allowed isolating faster growing mutants with growth rates increasing from 0.10 h-1 by the parental strain to 0.17 h-1 by the fastest mutant. Indeed, the fastest growing mutant produced glutarate with a twofold higher volumetric productivity of 0.18 g L-1 h-1 than the parental strain. Genome sequencing of the evolved strain revealed candidate mutations for improved production. Reverse genetic engineering revealed that an amino acid exchange in the large subunit of L-glutamic acid-2-oxoglutarate aminotransferase was causal for accelerated glutarate production and its beneficial effect was dependent on flux enforcement due to deletion of gdh. Performance of the evolved mutant was stable at the 2 L bioreactor-scale operated in batch and fed-batch mode in a mineral salts medium and reached a titer of 22.7 g L-1, a yield of 0.23 g g-1 and a volumetric productivity of 0.35 g L-1 h-1. Reactive extraction of glutarate directly from the fermentation broth was optimized leading to yields of 58% and 99% in the reactive extraction and reactive re-extraction step, respectively. The fermentation medium was adapted according to the downstream processing results. CONCLUSION Flux enforcement to couple growth to operation of a product biosynthesis pathway provides a basis to select strains growing and producing faster by adaptive laboratory evolution. After identifying candidate mutations by genome sequencing causal mutations can be identified by reverse genetics. As exemplified here for glutarate production by C. glutamicum, this approach allowed deducing rational metabolic engineering strategies.
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Affiliation(s)
- Carina Prell
- Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Tobias Busche
- Technology Platform Genomics, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, Germany
| | - Christian Rückert
- Technology Platform Genomics, Center for Biotechnology (CeBiTec), Bielefeld University, Sequenz 1, 33615 Bielefeld, Germany
| | - Lea Nolte
- Laboratory of Thermodynamics, Department of Biochemical and Chemical Engineering, TU Dortmund University, Emil-Figge-Str. 70, 44227 Dortmund, Germany
| | - Christoph Brandenbusch
- Laboratory of Thermodynamics, Department of Biochemical and Chemical Engineering, TU Dortmund University, Emil-Figge-Str. 70, 44227 Dortmund, Germany
| | - Volker F. Wendisch
- Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany
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Yu X, Shi F, Liu H, Tan S, Li Y. Programming adaptive laboratory evolution of 4-hydroxyisoleucine production driven by a lysine biosensor in Corynebacterium glutamicum. AMB Express 2021; 11:66. [PMID: 33963930 PMCID: PMC8106565 DOI: 10.1186/s13568-021-01227-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 04/29/2021] [Indexed: 11/10/2022] Open
Abstract
4-Hydroxyisoleucine (4-HIL) is a promising drug for treating diabetes. In our previous study, 4-HIL was synthesized from self-produced L-isoleucine (Ile) in Corynebacterium glutamicum by expressing an Ile dioxygenase gene. Although the 4-HIL production of recombinant strain SZ06 increased significantly, a by-product, L-lysine (Lys) was accumulated because of the share of the first several enzymes in Ile and Lys biosynthetic pathways. In this study, programming adaptive laboratory evolution (ALE) was designed and conducted in SZ06 to promote 4-HIL biosynthesis. At first, a programming evolutionary system pMK was constructed, which contains a Lys biosensor LysG-PlysE and an evolutionary actuator composed of a mutagenesis gene and a fluorescent protein gene. The evolutionary strain SZ06/pMK was then let to be evolved programmatically and spontaneously by sensing Lys concentration. After successive rounds of evolution, nine mutant strains K1 - K9 with significantly increased 4-HIL production and growth performance were obtained. The maximum 4-HIL titer was 152.19 ± 14.60 mM, 28.4% higher than that in SZ06. This titer was higher than those of all the metabolic engineered C. glutamicum strains ever constructed. The whole genome sequencing of the nine evolved strains revealed approximately 30 genetic mutations in each strain. Only one mutation was directly related to the Lys biosynthetic pathway. Therefore, programming ALE driven by Lys biosensor can be used as an effective strategy to increase 4-HIL production in C. glutamicum.
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Lee MJ, Park J, Park K, Kim JF, Kim P. Reverse Engineering Targets for Recombinant Protein Production in Corynebacterium glutamicum Inspired by a Fast-Growing Evolved Descendant. Front Bioeng Biotechnol 2020; 8:588070. [PMID: 33363126 PMCID: PMC7755716 DOI: 10.3389/fbioe.2020.588070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 11/09/2020] [Indexed: 11/13/2022] Open
Abstract
We previously reported a Corynebacterium glutamicum JH41 strain with a 58% faster growth rate through application of adaptive laboratory evolution. To verify that the fast-reproducing strain was useful as a host for recombinant protein expression, we introduced a plasmid responsible for the secretory production of a recombinant protein. The JH41 strain harboring the plasmid indeed produced the secretory recombinant protein at a 2.7-fold greater rate than its ancestral strain. To provide the reverse engineering targets responsible for boosting recombinant protein production and cell reproduction, we compared the genome sequence of the JH41 strain with its ancestral strain. Among the 15 genomic variations, a point mutation was confirmed in the 14 bases upstream of NCgl1959 (encoding a presumed siderophore-binding protein). This mutation allowed derepression of NCgl1959, thereby increasing iron consumption and ATP generation. A point mutation in the structural gene ramA (A239G), a LuxR-type global transcription regulator involved in central metabolism, allowed an increase in glucose consumption. Therefore, mutations to increase the iron and carbon consumption were concluded as being responsible for the enhanced production of recombinant protein and cell reproduction in the evolved host.
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Affiliation(s)
- Min Ju Lee
- Department of Biotechnology, The Catholic University of Korea, Gyeonggi, South Korea
| | - Jihoon Park
- Department of Biotechnology, The Catholic University of Korea, Gyeonggi, South Korea
| | - Kyunghoon Park
- Department of Biotechnology, The Catholic University of Korea, Gyeonggi, South Korea
| | - Jihyun F Kim
- Department of Systems Biology, Division of Life Sciences, and Institute for Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Pil Kim
- Department of Biotechnology, The Catholic University of Korea, Gyeonggi, South Korea
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Disruption of the Oxidative Pentose Phosphate Pathway Stimulates High-Yield Production Using Resting Corynebacterium glutamicum in the Absence of External Electron Acceptors. Appl Environ Microbiol 2020; 86:AEM.02114-20. [PMID: 33036990 DOI: 10.1128/aem.02114-20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 10/02/2020] [Indexed: 01/22/2023] Open
Abstract
Identifying and overcoming the limitations preventing efficient high-yield production of chemicals remain important tasks in metabolic engineering. In an attempt to rewire Corynebacterium glutamicum to produce ethanol, we attained a low yield (63% of the theoretical) when using resting cells on glucose, and large amounts of succinate and acetate were formed. To prevent the by-product formation, we knocked out the malate dehydrogenase and replaced the native E3 subunit of the pyruvate dehydrogenase complex (PDHc) with that from Escherichia coli, which is active only under aerobic conditions. However, this tampering resulted in a 10-times-reduced glycolytic flux as well as a greatly increased NADH/NAD+ ratio. When we replaced glucose with fructose, we found that the glycolytic flux was greatly enhanced, which led us to speculate whether the source of reducing power could be the pentose phosphate pathway (PPP) that is bypassed when fructose is metabolized. Indeed, after shutting down the PPP by deleting the zwf gene, encoding glucose-6-phosphate dehydrogenase, the ethanol yield on glucose increased significantly, to 92% of the theoretical. Based on that, we managed to rechannel the metabolism of C. glutamicum into d-lactate with high yield, 98%, which is the highest that has been reported. It is further demonstrated that the PPP-inactivated platform strain can offer high-yield production of valuable chemicals using lactose contained in dairy waste as feedstock, which paves a promising way for potentially turning dairy waste into a valuable product.IMPORTANCE The widely used industrial workhorse C. glutamicum possesses a complex anaerobic metabolism under nongrowing conditions, and we demonstrate here that the PPP in resting C. glutamicum is a source of reducing power that can interfere with otherwise redox-balanced metabolic pathways and reduce yields of desired products. By harnessing this physiological insight, we employed the PPP-inactivated platform strains to produce ethanol, d-lactate, and alanine using the dairy waste whey permeate as the feedstock. The production yield was high, and our results show that inactivation of the PPP flux in resting cells is a promising strategy when the aim is to use nongrowing C. glutamicum cells for producing valuable compounds. Overall, we describe the benefits of disrupting the oxidative PPP in nongrowing C. glutamicum and provide a feasible approach toward waste valorization.
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Graf M, Haas T, Teleki A, Feith A, Cerff M, Wiechert W, Nöh K, Busche T, Kalinowski J, Takors R. Revisiting the Growth Modulon of Corynebacterium glutamicum Under Glucose Limited Chemostat Conditions. Front Bioeng Biotechnol 2020; 8:584614. [PMID: 33178676 PMCID: PMC7594717 DOI: 10.3389/fbioe.2020.584614] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 09/23/2020] [Indexed: 11/13/2022] Open
Abstract
Increasing the growth rate of the industrial host Corynebacterium glutamicum is a promising target to rise productivities of growth coupled product formation. As a prerequisite, detailed knowledge about the tight regulation network is necessary for identifying promising metabolic engineering goals. Here, we present comprehensive metabolic and transcriptional analysis of C. glutamicum ATCC 13032 growing under glucose limited chemostat conditions with μ = 0.2, 0.3, and 0.4 h–1. Intermediates of central metabolism mostly showed rising pool sizes with increasing growth. 13C-metabolic flux analysis (13C-MFA) underlined the fundamental role of central metabolism for the supply of precursors, redox, and energy equivalents. Global, growth-associated, concerted transcriptional patterns were not detected giving rise to the conclusion that glycolysis, pentose-phosphate pathway, and citric acid cycle are predominately metabolically controlled under glucose-limiting chemostat conditions. However, evidence is found that transcriptional regulation takes control over glycolysis once glucose-rich growth conditions are installed.
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Affiliation(s)
- Michaela Graf
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Thorsten Haas
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Attila Teleki
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - André Feith
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Martin Cerff
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Wolfgang Wiechert
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Katharina Nöh
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Tobias Busche
- Center for Biotechnology, Bielefeld University, Bielefeld, Germany.,Institute for Biology-Microbiology, Freie Universität Berlin, Berlin, Germany
| | - Jörn Kalinowski
- Center for Biotechnology, Bielefeld University, Bielefeld, Germany
| | - Ralf Takors
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
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Pinheiro B, Petrov DP, Guo L, Martins GB, Bramkamp M, Jung K. Elongation factor P is required for EII Glc translation in Corynebacterium glutamicum due to an essential polyproline motif. Mol Microbiol 2020; 115:320-331. [PMID: 33012080 DOI: 10.1111/mmi.14618] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 09/25/2020] [Indexed: 12/22/2022]
Abstract
Translating ribosomes require elongation factor P (EF-P) to incorporate consecutive prolines (XPPX) into nascent peptide chains. The proteome of Corynebacterium glutamicum ATCC 13032 contains a total of 1,468 XPPX motifs, many of which are found in proteins involved in primary and secondary metabolism. We show here that synthesis of EIIGlc , the glucose-specific permease of the phosphoenolpyruvate (PEP): sugar phosphotransferase system (PTS) encoded by ptsG, is strongly dependent on EF-P, as an efp deletion mutant grows poorly on glucose as sole carbon source. The amount of EIIGlc is strongly reduced in this mutant, which consequently results in a lower rate of glucose uptake. Strikingly, the XPPX motif is essential for the activity of EIIGlc , and substitution of the prolines leads to inactivation of the protein. Finally, translation of GntR2, a transcriptional activator of ptsG, is also dependent on EF-P. However, its reduced amount in the efp mutant can be compensated for by other regulators. These results reveal for the first time a translational bottleneck involving production of the major glucose transporter EIIGlc , which has implications for future strain engineering strategies.
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Affiliation(s)
- Bruno Pinheiro
- Department of Biology I, Microbiology, Ludwig-Maximilians-Universität München, Martinsried, Germany
| | - Dimitar Plamenov Petrov
- Department of Biology I, Microbiology, Ludwig-Maximilians-Universität München, Martinsried, Germany
| | - Lingyun Guo
- Department of Biology I, Microbiology, Ludwig-Maximilians-Universität München, Martinsried, Germany
| | | | - Marc Bramkamp
- Institute for General Microbiology, Faculty of Mathematics and Natural Sciences, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
| | - Kirsten Jung
- Department of Biology I, Microbiology, Ludwig-Maximilians-Universität München, Martinsried, Germany
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Park J, Lee S, Lee MJ, Park K, Lee S, Kim JF, Kim P. Accelerated Growth of Corynebacterium glutamicum by Up-Regulating Stress- Responsive Genes Based on Transcriptome Analysis of a Fast-Doubling Evolved Strain. J Microbiol Biotechnol 2020; 30:1420-1429. [PMID: 32699195 PMCID: PMC9728273 DOI: 10.4014/jmb.2006.06035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/06/2020] [Accepted: 07/09/2020] [Indexed: 12/15/2022]
Abstract
Corynebacterium glutamicum, an important industrial strain, has a relatively slower reproduction rate. To acquire a growth-boosted C. glutamicum, a descendant strain was isolated from a continuous culture after 600 generations. The isolated descendant C. glutamicum, JH41 strain, was able to double 58% faster (td=1.15 h) than the parental type strain (PT, td=1.82 h). To understand the factors boosting reproduction, the transcriptomes of JH41 and PT strains were compared. The mRNAs involved in respiration and TCA cycle were upregulated. The intracellular ATP of the JH41 strain was 50% greater than the PT strain. The upregulation of NCgl1610 operon (a putative dyp-type heme peroxidase, a putative copper chaperone, and a putative copper importer) that presumed to role in the assembly and redox control of cytochrome c oxidase was found in the JH41 transcriptome. Plasmid-driven expression of the operon enabled the PT strain to double 19% faster (td=1.82 h) than its control (td=2.17 h) with 14% greater activity of cytochrome c oxidase and 27% greater intracellular ATP under the oxidative stress conditions. Upregulations of genes those might enhance translation fitness were also found in the JH41 transcriptome. Plasmid-driven expressions of NCgl0171 (encoding a cold-shock protein) and NCgl2435 (encoding a putative peptidyl-tRNA hydrolase) enabled the PT to double 22% and 32% faster than its control, respectively (empty vector: td=1.93 h, CspA: td=1.58 h, and Pth: td=1.44 h). Based on the results, the factors boosting growth rate in C. gluctamicum were further discussed in the viewpoints of cellular energy state, oxidative stress management, and translation.
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Affiliation(s)
- Jihoon Park
- Department of Biotechnology, The Catholic University of Korea, Gyeonggi 14662, Republic of Korea
| | - SuRin Lee
- Department of Biotechnology, The Catholic University of Korea, Gyeonggi 14662, Republic of Korea
| | - Min Ju Lee
- Department of Biotechnology, The Catholic University of Korea, Gyeonggi 14662, Republic of Korea
| | - Kyunghoon Park
- Department of Biotechnology, The Catholic University of Korea, Gyeonggi 14662, Republic of Korea
| | - Seungki Lee
- Department of Biotechnology, The Catholic University of Korea, Gyeonggi 14662, Republic of Korea
| | - Jihyun F. Kim
- Department of Systems Biology, Division of Life Sciences, and Institute for Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Pil Kim
- Department of Biotechnology, The Catholic University of Korea, Gyeonggi 14662, Republic of Korea,Corresponding author Phone/Fax: +82-2-2164-4922 E-mail:
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Valanciene E, Jonuskiene I, Syrpas M, Augustiniene E, Matulis P, Simonavicius A, Malys N. Advances and Prospects of Phenolic Acids Production, Biorefinery and Analysis. Biomolecules 2020; 10:E874. [PMID: 32517243 PMCID: PMC7356249 DOI: 10.3390/biom10060874] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 05/28/2020] [Accepted: 06/03/2020] [Indexed: 12/20/2022] Open
Abstract
Biotechnological production of phenolic acids is attracting increased interest due to their superior antioxidant activity, as well as other antimicrobial, dietary, and health benefits. As secondary metabolites, primarily found in plants and fungi, they are effective free radical scavengers due to the phenolic group available in their structure. Therefore, phenolic acids are widely utilised by pharmaceutical, food, cosmetic, and chemical industries. A demand for phenolic acids is mostly satisfied by utilising chemically synthesised compounds, with only a low quantity obtained from natural sources. As an alternative to chemical synthesis, environmentally friendly bio-based technologies are necessary for development in large-scale production. One of the most promising sustainable technologies is the utilisation of microbial cell factories for biosynthesis of phenolic acids. In this paper, we perform a systematic comparison of the best known natural sources of phenolic acids. The advances and prospects in the development of microbial cell factories for biosynthesis of these bioactive compounds are discussed in more detail. A special consideration is given to the modern production methods and analytics of phenolic acids.
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Affiliation(s)
| | | | | | | | | | | | - Naglis Malys
- Bioprocess Research Centre, Faculty of Chemical Technology, Kaunas University of Technology, Radvilėnų pl. 19, Kaunas LT-50254, Lithuania; (E.V.); (I.J.); (M.S.); (E.A.); (P.M.); (A.S.)
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14
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Diao J, Song X, Guo T, Wang F, Chen L, Zhang W. Cellular engineering strategies toward sustainable omega-3 long chain polyunsaturated fatty acids production: State of the art and perspectives. Biotechnol Adv 2020; 40:107497. [DOI: 10.1016/j.biotechadv.2019.107497] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 12/06/2019] [Accepted: 12/06/2019] [Indexed: 12/28/2022]
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15
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Graf M, Haas T, Müller F, Buchmann A, Harm-Bekbenbetova J, Freund A, Nieß A, Persicke M, Kalinowski J, Blombach B, Takors R. Continuous Adaptive Evolution of a Fast-Growing Corynebacterium glutamicum Strain Independent of Protocatechuate. Front Microbiol 2019; 10:1648. [PMID: 31447790 PMCID: PMC6691914 DOI: 10.3389/fmicb.2019.01648] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Accepted: 07/03/2019] [Indexed: 12/30/2022] Open
Abstract
Corynebacterium glutamicum is a commonly applied host for the industrial production of amino acids. While valued for its robustness, it is somewhat inferior to competing strains such as Escherichia coli because of the relatively low growth rate of 0.40 h−1 in synthetic, industrial media. Accordingly, adaptive laboratory evolution (ALE) experiments were performed in continuous cultivation mode to select for a growth-improved host. To ensure industrial attractiveness, this ALE study aimed at a reduction of dependency on costly growth-boosting additives such as protocatechuate (PCA) or complex media supplements. Consequently, double selection pressures were installed consisting of a steady increase in growth rate demands and a parallel reduction of complex medium fractions. Selection yielded C. glutamicum EVO5 achieving 0.54 h−1 and 1.03 gGlc gCDW−1 h−1 in minimal medium without abovementioned supplements. Sequencing revealed 10 prominent mutations, three of them in key regulator genes.
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Affiliation(s)
- Michaela Graf
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Thorsten Haas
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Felix Müller
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Anina Buchmann
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | | | - Andreas Freund
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Alexander Nieß
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Marcus Persicke
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - Jörn Kalinowski
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - Bastian Blombach
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany.,Microbial Biotechnology, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Straubing, Germany
| | - Ralf Takors
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
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16
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Stella RG, Wiechert J, Noack S, Frunzke J. Evolutionary engineering of
Corynebacterium glutamicum. Biotechnol J 2019; 14:e1800444. [DOI: 10.1002/biot.201800444] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/23/2019] [Indexed: 01/02/2023]
Affiliation(s)
- Roberto G. Stella
- Institute of Bio‐ and Geosciences, IBG‐1: Biotechnology, Forschungszentrum Jülich Wilhelm‐Johnen‐Straße 52428 Jülich Germany
| | - Johanna Wiechert
- Institute of Bio‐ and Geosciences, IBG‐1: Biotechnology, Forschungszentrum Jülich Wilhelm‐Johnen‐Straße 52428 Jülich Germany
| | - Stephan Noack
- Institute of Bio‐ and Geosciences, IBG‐1: Biotechnology, Forschungszentrum Jülich Wilhelm‐Johnen‐Straße 52428 Jülich Germany
| | - Julia Frunzke
- Institute of Bio‐ and Geosciences, IBG‐1: Biotechnology, Forschungszentrum Jülich Wilhelm‐Johnen‐Straße 52428 Jülich Germany
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17
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Haas T, Graf M, Nieß A, Busche T, Kalinowski J, Blombach B, Takors R. Identifying the Growth Modulon of Corynebacterium glutamicum. Front Microbiol 2019; 10:974. [PMID: 31134020 PMCID: PMC6517550 DOI: 10.3389/fmicb.2019.00974] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 04/18/2019] [Indexed: 12/16/2022] Open
Abstract
The growth rate (μ) of industrially relevant microbes, such as Corynebacterium glutamicum, is a fundamental property that indicates its production capacity. Therefore, understanding the mechanism underlying the growth rate is imperative for improving productivity and performance through metabolic engineering. Despite recent progress in the understanding of global regulatory interactions, knowledge of mechanisms directing cell growth remains fragmented and incomplete. The current study investigated RNA-Seq data of three growth rate transitions, induced by different pre-culture conditions, in order to identify transcriptomic changes corresponding to increasing growth rates. These transitions took place in minimal medium and ranged from 0.02 to 0.4 h-1 μ. This study enabled the identification of 447 genes as components of the growth modulon. Enrichment of genes within the growth modulon revealed 10 regulons exhibiting a significant effect over growth rate transition. In summary, central metabolism was observed to be regulated by a combination of metabolic and transcriptional activities orchestrating control over glycolysis, pentose phosphate pathway, and the tricarboxylic acid cycle. Additionally, major responses to changes in the growth rate were linked to iron uptake and carbon metabolism. In particular, genes encoding glycolytic enzymes and the glucose uptake system showed a positive correlation with the growth rate.
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Affiliation(s)
- Thorsten Haas
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Michaela Graf
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Alexander Nieß
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
| | - Tobias Busche
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany.,Institute for Biology-Microbiology, Freie Universität Berlin, Berlin, Germany
| | - Jörn Kalinowski
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - Bastian Blombach
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany.,Microbial Biotechnology, Campus Straubing for Biotechnology and Sustainability, Technical University of Munich, Straubing, Germany
| | - Ralf Takors
- Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany
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18
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Wendisch VF. Metabolic engineering advances and prospects for amino acid production. Metab Eng 2019; 58:17-34. [PMID: 30940506 DOI: 10.1016/j.ymben.2019.03.008] [Citation(s) in RCA: 141] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 03/26/2019] [Accepted: 03/26/2019] [Indexed: 11/18/2022]
Abstract
Amino acid fermentation is one of the major pillars of industrial biotechnology. The multi-billion USD amino acid market is rising steadily and is diversifying. Metabolic engineering is no longer focused solely on strain development for the bulk amino acids L-glutamate and L-lysine that are produced at the million-ton scale, but targets specialty amino acids. These demands are met by the development and application of new metabolic engineering tools including CRISPR and biosensor technologies as well as production processes by enabling a flexible feedstock concept, co-production and co-cultivation schemes. Metabolic engineering advances are exemplified for specialty proteinogenic amino acids, cyclic amino acids, omega-amino acids, and amino acids functionalized by hydroxylation, halogenation and N-methylation.
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Affiliation(s)
- Volker F Wendisch
- Genetics of Prokaryotes, Faculty of Biology and Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany.
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19
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Pérez-García F, Jorge JMP, Dreyszas A, Risse JM, Wendisch VF. Efficient Production of the Dicarboxylic Acid Glutarate by Corynebacterium glutamicum via a Novel Synthetic Pathway. Front Microbiol 2018; 9:2589. [PMID: 30425699 PMCID: PMC6218589 DOI: 10.3389/fmicb.2018.02589] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 10/10/2018] [Indexed: 12/04/2022] Open
Abstract
The dicarboxylic acid glutarate is an important building-block gaining interest in the chemical and pharmaceutical industry. Here, a synthetic pathway for fermentative production of glutarate by the actinobacterium Corynebacterium glutamicum has been developed. The pathway does not require molecular oxygen and operates via lysine decarboyxylase followed by two transamination and two NAD-dependent oxidation reactions. Using a genome-streamlined L-lysine producing strain as basis, metabolic engineering was performed to enable conversion of L-lysine to glutarate in a five-step synthetic pathway comprising lysine decarboxylase, putrescine transaminase and γ-aminobutyraldehyde dehydrogenase from Escherichia coli and GABA/5AVA amino transferase and succinate/glutarate semialdehyde dehydrogenase either from C. glutamicum or from three Pseudomonas species. Loss of carbon via formation of the by-products cadaverine and N-acetylcadaverine was avoided by deletion of the respective acetylase and export genes. As the two transamination reactions in the synthetic glutarate biosynthesis pathway yield L-glutamate, biosynthesis of L-glutamate by glutamate dehydrogenase was expected to be obsolete and, indeed, deletion of its gene gdh increased glutarate titers by 10%. Glutarate production by the final strain was tested in bioreactors (n = 2) in order to investigate stability and reliability of the process. The most efficient glutarate production from glucose was achieved by fed-batch fermentation (n = 1) with a volumetric productivity of 0.32 g L-1 h-1, an overall yield of 0.17 g g-1 and a titer of 25 g L-1.
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Affiliation(s)
- Fernando Pérez-García
- Chair of Genetics of Prokaryotes, Faculty of Biology and CeBiTec, Bielefeld University, Bielefeld, Germany
| | - João M P Jorge
- Chair of Genetics of Prokaryotes, Faculty of Biology and CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Annika Dreyszas
- Chair of Genetics of Prokaryotes, Faculty of Biology and CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Joe Max Risse
- Fermentation Technology, Technical Faculty and CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Volker F Wendisch
- Chair of Genetics of Prokaryotes, Faculty of Biology and CeBiTec, Bielefeld University, Bielefeld, Germany
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20
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Diao J, Song X, Cui J, Liu L, Shi M, Wang F, Zhang W. Rewiring metabolic network by chemical modulator based laboratory evolution doubles lipid production in Crypthecodinium cohnii. Metab Eng 2018; 51:88-98. [PMID: 30393203 DOI: 10.1016/j.ymben.2018.10.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Revised: 09/16/2018] [Accepted: 10/21/2018] [Indexed: 12/01/2022]
Abstract
Dietary omega-3 long-chain polyunsaturated fatty acids docosahexaenoic acid (DHA, C22:6) can be synthesized in microalgae Crypthecodinium cohnii; however, its productivity is still low. Here, we established a new protocol termed as "chemical modulator based adaptive laboratory evolution" (CM-ALE) to enhance lipid and DHA productivity in C. cohnii. First, ACCase inhibitor sethoxydim based CM-ALE was applied to redirect carbon equivalents from starch to lipid. Second, CM-ALE using growth modulator sesamol as selection pressure was conducted to relive negative effects of sesamol on lipid biosynthesis in C. cohnii, which allows enhancement of biomass productivity by 30% without decreasing lipid content when sesamol was added. After two-step CM-ALE, the lipid and DHA productivity in C. cohnii was respectively doubled to a level of 0.046 g/L/h and 0.025 g/L/h in culture with addition of 1 mM sesamol, demonstrating that this two-step CM-ALE could be a valuable approach to maximize the properties of microalgae.
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Affiliation(s)
- Jinjin Diao
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, PR China; Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, PR China
| | - Xinyu Song
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, PR China; Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, PR China; Center for Biosafety Research and Strategy, Tianjin University, Tianjin, PR China
| | - Jinyu Cui
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, PR China; Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, PR China
| | - Liangsen Liu
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, PR China; Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, PR China
| | - Mengliang Shi
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, PR China; Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, PR China
| | - Fangzhong Wang
- Center for Biosafety Research and Strategy, Tianjin University, Tianjin, PR China
| | - Weiwen Zhang
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, PR China; Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, PR China; Center for Biosafety Research and Strategy, Tianjin University, Tianjin, PR China.
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