1
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Liu J, Liu D, Sun T, Fan TP, Cai Y. Construction and characterization of a promoter library with varying strengths to enhance acetoin production from xylose in Serratia marcescens. Biotechnol Appl Biochem 2024; 71:553-564. [PMID: 38225826 DOI: 10.1002/bab.2558] [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: 08/18/2023] [Accepted: 12/30/2023] [Indexed: 01/17/2024]
Abstract
Serratia marcescens is utilized as a significant enterobacteria in the production of various high-value secondary metabolites. Acetoin serves as a crucial foundational compound of development and finds application in a broad range of fields. Furthermore, S. marcescens HBQA-7 is capable of utilizing xylose as its exclusive carbon source for acetoin production. The objective of this study was to utilize a constitutive promoter screening strategy to enhance both xylose utilization and acetoin production in S. marcescens HBQA-7. By utilizing RNA-seq, we identified the endogenous constitutive promoter P6 that is the most robust, which facilitated the overexpression of the sugar transporter protein GlfL445I, α-acetyl lactate synthase, and α-acetyl lactate decarboxylase, respectively. The resultant recombinant strains exhibited enhanced xylose utilization rates and acetoin yields. Subsequently, a recombinant plasmid, denoted as pBBR1MCS-P6-glfL445IalsSalsD, was constructed, simultaneously expressing the aforementioned three genes. The resulting recombinant strain, designated as S3, demonstrated a 1.89-fold boost in xylose consumption rate compared with the original strain during shake flask fermentation. resulting in the accumulation of 7.14 g/L acetoin in the final fermentation medium. Subsequently, in a 5 L fermenter setup, the acetoin yield reached 48.75 g/L, corresponding to a xylose-to-acetoin conversion yield of 0.375 g/g.
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Affiliation(s)
- Jie Liu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Di Liu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Tingting Sun
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Tai-Ping Fan
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Yujie Cai
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
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2
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Choi JW, Song NE, Hong SP, Rhee YK, Hong HD, Cho CW. Engineering Bacillus subtilis J46 for efficient utilization of galactose through adaptive laboratory evolution. AMB Express 2024; 14:14. [PMID: 38282124 PMCID: PMC10822834 DOI: 10.1186/s13568-024-01666-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 01/08/2024] [Indexed: 01/30/2024] Open
Abstract
Efficient utilization of galactose by microorganisms can lead to the production of valuable bio-products and improved metabolic processes. While Bacillus subtilis has inherent pathways for galactose metabolism, there is potential for enhancement via evolutionary strategies. This study aimed to boost galactose utilization in B. subtilis using adaptive laboratory evolution (ALE) and to elucidate the genetic and metabolic changes underlying the observed enhancements. The strains of B. subtilis underwent multiple rounds of adaptive laboratory evolution (approximately 5000 generations) in an environment that favored the use of galactose. This process resulted in an enhanced specific growth rate of 0.319 ± 0.005 h-1, a significant increase from the 0.03 ± 0.008 h-1 observed in the wild-type strains. Upon selecting the evolved strain BSGA14, a comprehensive whole-genome sequencing revealed the presence of 63 single nucleotide polymorphisms (SNPs). Two of them, located in the coding sequences of the genes araR and glcR, were found to be the advantageous mutations after reverse engineering. The strain with these two accumulated mutations, BSGALE4, exhibited similar specific growth rate on galactose to the evolved strain BSGA14 (0.296 ± 0.01 h-1). Furthermore, evolved strain showed higher productivity of protease and β-galactosidase in mock soybean biomass medium. ALE proved to be a potent tool for enhancing galactose metabolism in B. subtilis. The findings offer valuable insights into the potential of evolutionary strategies in microbial engineering and pave the way for industrial applications harnessing enhanced galactose conversion.
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Affiliation(s)
- Jae Woong Choi
- Research Group of Traditional Food, Korea Food Research Institute, 245, Nongsaengmyeong-ro, Iseo-myeon, Wanju-gun, 55365, Republic of Korea
| | - Nho-Eul Song
- Research Group of Traditional Food, Korea Food Research Institute, 245, Nongsaengmyeong-ro, Iseo-myeon, Wanju-gun, 55365, Republic of Korea
| | - Sang-Pil Hong
- Research Group of Traditional Food, Korea Food Research Institute, 245, Nongsaengmyeong-ro, Iseo-myeon, Wanju-gun, 55365, Republic of Korea
| | - Young Kyoung Rhee
- Research Group of Traditional Food, Korea Food Research Institute, 245, Nongsaengmyeong-ro, Iseo-myeon, Wanju-gun, 55365, Republic of Korea
| | - Hee-Do Hong
- Research Group of Traditional Food, Korea Food Research Institute, 245, Nongsaengmyeong-ro, Iseo-myeon, Wanju-gun, 55365, Republic of Korea
| | - Chang-Won Cho
- Research Group of Traditional Food, Korea Food Research Institute, 245, Nongsaengmyeong-ro, Iseo-myeon, Wanju-gun, 55365, Republic of Korea.
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3
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Wang G, Li Q, Zhang Z, Yin X, Wang B, Yang X. Recent progress in adaptive laboratory evolution of industrial microorganisms. J Ind Microbiol Biotechnol 2022; 50:6794275. [PMID: 36323428 PMCID: PMC9936214 DOI: 10.1093/jimb/kuac023] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Accepted: 10/24/2022] [Indexed: 01/12/2023]
Abstract
Adaptive laboratory evolution (ALE) is a technique for the selection of strains with better phenotypes by long-term culture under a specific selection pressure or growth environment. Because ALE does not require detailed knowledge of a variety of complex and interactive metabolic networks, and only needs to simulate natural environmental conditions in the laboratory to design a selection pressure, it has the advantages of broad adaptability, strong practicability, and more convenient transformation of strains. In addition, ALE provides a powerful method for studying the evolutionary forces that change the phenotype, performance, and stability of strains, resulting in more productive industrial strains with beneficial mutations. In recent years, ALE has been widely used in the activation of specific microbial metabolic pathways and phenotypic optimization, the efficient utilization of specific substrates, the optimization of tolerance to toxic substance, and the biosynthesis of target products, which is more conducive to the production of industrial strains with excellent phenotypic characteristics. In this paper, typical examples of ALE applications in the development of industrial strains and the research progress of this technology are reviewed, followed by a discussion of its development prospects.
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Affiliation(s)
| | | | - Zhan Zhang
- Technology Center, China Tobacco Henan Industrial Co., Ltd. Zhengzhou, Henan 450000, People's Republic of China
| | - Xianzhong Yin
- Technology Center, China Tobacco Henan Industrial Co., Ltd. Zhengzhou, Henan 450000, People's Republic of China
| | - Bingyang Wang
- Laboratory of Biotransformation and Biocatalysis, School of Tobacco Science and Engineering, Zhengzhou University of Light Industry, Zhengzhou, Henan 450000, People's Republic of China
| | - Xuepeng Yang
- Correspondence should be addressed to: Xuepeng Yang, Zhengzhou University of Light Industry, Dongfeng Road 5, Zhengzhou, Henan 450002, People's Republic of China. Tel.: +86-152-3712-7687. Fax: +86-0371-8660-8262. E-mail:
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4
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Wang G, Wang M, Liu L, Hui X, Wang B, Ma K, Yang X. Improvement of the catalytic performance of glycerol kinase from Bacillus subtilis by chromosomal site-directed mutagenesis. Biotechnol Lett 2022; 44:1051-1061. [PMID: 35922648 DOI: 10.1007/s10529-022-03281-8] [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: 01/29/2022] [Accepted: 07/11/2022] [Indexed: 11/24/2022]
Abstract
Glycerol kinase is the key enzyme in glycerol metabolism, and its catalytic efficiency has an important effect on glycerol utilization. Based on an analysis of the glycerol utilization pathway and regulation mechanism in B. subtilis, we conducted site-directed mutagenesis of the key glycerol kinase gene (glpK) on the chromosome to improve the glycerol utilization efficiency of Bacillus subtilis. Recombinant wild-type Bacillus subtilis glycerol kinase (BsuGlpKWT) and two mutants (BsuGlpKM270I and BsuGlpKS71V) were successfully overexpressed in Escherichia coli BL21(DE3) and purified by Ni-IDA metal chelate chromatography. The specific activity of the BsuGlpKM270I mutant (62.6 U/mg) was significantly higher (296.2%) than that of wild-type BsuGlpKWT (15.8 U/mg). By contrast, the mutant BsuGlpKS71V (4.89 U/mg) exhibited lower (69.1%) activity than BsuGlpKWT, which suggested that variant S71V exhibited reduced catalytic efficiency for the substrate. Furthermore, the mutant strain B. subtilis M270I was constructed using a markerless delivery system, and exhibited a higher specific growth rate (improved by 11.3%, from 0.453 ± 0.012 to 0.511 ± 0.017 h-1) and higher maximal biomass (cell dry weight increased by 16%, from 0.577 ± 0.033 to 0.721 ± 0.015 g/L) than the parental strain with a shortened lag phase (2 ~ 4 h shorter) in M9 minimal medium with glycerol. These results indicate that the mutated glpK resulted in improved glycerol utilization, which has broad application prospects.
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Affiliation(s)
- Guanglu Wang
- Laboratory of Biotransformation and Biocatalysis, School of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Dongfeng Road 5, Henan, 450000, People's Republic of China.,School of Food and Bioengineering/Collaborative Innovation Center for Food Production and Safety, Zhengzhou University of Light Industry, Dongfeng Road 5, Zhengzhou, Henan, 450001, People's Republic of China
| | - Mengyuan Wang
- Laboratory of Biotransformation and Biocatalysis, School of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Dongfeng Road 5, Henan, 450000, People's Republic of China.,School of Food and Bioengineering/Collaborative Innovation Center for Food Production and Safety, Zhengzhou University of Light Industry, Dongfeng Road 5, Zhengzhou, Henan, 450001, People's Republic of China
| | - Lanxi Liu
- Laboratory of Biotransformation and Biocatalysis, School of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Dongfeng Road 5, Henan, 450000, People's Republic of China.,School of Food and Bioengineering/Collaborative Innovation Center for Food Production and Safety, Zhengzhou University of Light Industry, Dongfeng Road 5, Zhengzhou, Henan, 450001, People's Republic of China
| | - Xiaohan Hui
- Laboratory of Biotransformation and Biocatalysis, School of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Dongfeng Road 5, Henan, 450000, People's Republic of China.,School of Food and Bioengineering/Collaborative Innovation Center for Food Production and Safety, Zhengzhou University of Light Industry, Dongfeng Road 5, Zhengzhou, Henan, 450001, People's Republic of China
| | - Bingyang Wang
- Laboratory of Biotransformation and Biocatalysis, School of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Dongfeng Road 5, Henan, 450000, People's Republic of China.,School of Food and Bioengineering/Collaborative Innovation Center for Food Production and Safety, Zhengzhou University of Light Industry, Dongfeng Road 5, Zhengzhou, Henan, 450001, People's Republic of China
| | - Ke Ma
- Laboratory of Biotransformation and Biocatalysis, School of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Dongfeng Road 5, Henan, 450000, People's Republic of China.,School of Food and Bioengineering/Collaborative Innovation Center for Food Production and Safety, Zhengzhou University of Light Industry, Dongfeng Road 5, Zhengzhou, Henan, 450001, People's Republic of China
| | - Xuepeng Yang
- Laboratory of Biotransformation and Biocatalysis, School of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou, Dongfeng Road 5, Henan, 450000, People's Republic of China. .,School of Food and Bioengineering/Collaborative Innovation Center for Food Production and Safety, Zhengzhou University of Light Industry, Dongfeng Road 5, Zhengzhou, Henan, 450001, People's Republic of China.
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5
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Gao W, Yin Y, Wang P, Tan W, He M, Wen J. Production of fengycin from D-xylose through the expression and metabolic regulation of the Dahms pathway. Appl Microbiol Biotechnol 2022; 106:2557-2567. [PMID: 35362719 DOI: 10.1007/s00253-022-11871-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Revised: 02/14/2022] [Accepted: 03/05/2022] [Indexed: 12/01/2022]
Abstract
D-Xylose is a key component of lignocellulosic biomass and the second-most abundant carbohydrate on the planet. As one of the most powerful cyclo-lipopeptide antibiotics, fengycin displays strong wide-spectrum antifungal and antiviral, as well as potential anti-cancer activity. Pyruvate is a key metabolite linking the biosynthesis of fatty acids and amino acids, the precursors for fengycin. In this study, the genes encoding the Dahms xylose-utilization pathway were integrated into the amyE site of Bacillus subtilis 168, and based on the metabolic characteristics of the Dahms pathway, the acetate kinase (ackA) and lactate dehydrogenase (ldh) genes were knocked out. Then, the metabolic control module II was designed to convert glycolaldehyde, another intermediate of the Dahms pathway, in addition to pathways for the conversion of acetaldehyde into malic acid and oxaloacetic acid, resulting in strain BSU03. In the presence of module II, the content of acetic and lactic acid decreased significantly, and the xylose uptake efficiency increased. At the same time, the yield of fengycin increased by 87% compared to the original strain. Additionally, the underlying factors for the increase of fengycin titer were revealed through metabonomic analysis. This study therefore demonstrates that this regulation approach can not only optimize the intracellular fluxes for the Dahms pathway, but is also conducive to the synthesis of secondary metabolites similar to fengycin. KEY POINTS: • The expression and effect of the Dahms pathway on the synthesis of fengycin in Bacillus subtilis 168. • The expression of regulatory module II can promote the metabolic rate of the Dahms pathway and increase the synthesis of the fengycin.
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Affiliation(s)
- Wenting Gao
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
| | - Ying Yin
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
| | - Pan Wang
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
| | - Wei Tan
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
| | - Mingliang He
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China
| | - Jianping Wen
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, China. .,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China. .,Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin, China.
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6
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Mavrommati M, Daskalaki A, Papanikolaou S, Aggelis G. Adaptive laboratory evolution principles and applications in industrial biotechnology. Biotechnol Adv 2021; 54:107795. [PMID: 34246744 DOI: 10.1016/j.biotechadv.2021.107795] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 06/11/2021] [Accepted: 07/05/2021] [Indexed: 12/20/2022]
Abstract
Adaptive laboratory evolution (ALE) is an innovative approach for the generation of evolved microbial strains with desired characteristics, by implementing the rules of natural selection as presented in the Darwinian Theory, on the laboratory bench. New as it might be, it has already been used by several researchers for the amelioration of a variety of characteristics of widely used microorganisms in biotechnology. ALE is used as a tool for the deeper understanding of the genetic and/or metabolic pathways of evolution. Another important field targeted by ALE is the manufacturing of products of (high) added value, such as ethanol, butanol and lipids. In the current review, we discuss the basic principles and techniques of ALE, and then we focus on studies where it has been applied to bacteria, fungi and microalgae, aiming to improve their performance to biotechnological procedures and/or inspect the genetic background of evolution. We conclude that ALE is a promising and efficacious method that has already led to the acquisition of useful new microbiological strains in biotechnology and could possibly offer even more interesting results in the future.
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Affiliation(s)
- Maria Mavrommati
- Unit of Microbiology, Department of Biology, Division of Genetics, Cell Biology and Development, University of Patras, 26504 Patras, Greece; Laboratory of Food Microbiology and Biotechnology, Department of Food Science and Human Nutrition, Agricultural University of Athens, 75 Iera Odos, 11855 Athens, Greece
| | - Alexandra Daskalaki
- Unit of Microbiology, Department of Biology, Division of Genetics, Cell Biology and Development, University of Patras, 26504 Patras, Greece
| | - Seraphim Papanikolaou
- Laboratory of Food Microbiology and Biotechnology, Department of Food Science and Human Nutrition, Agricultural University of Athens, 75 Iera Odos, 11855 Athens, Greece
| | - George Aggelis
- Unit of Microbiology, Department of Biology, Division of Genetics, Cell Biology and Development, University of Patras, 26504 Patras, Greece.
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7
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Production of proteins and commodity chemicals using engineered Bacillus subtilis platform strain. Essays Biochem 2021; 65:173-185. [PMID: 34028523 DOI: 10.1042/ebc20210011] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 05/02/2021] [Accepted: 05/06/2021] [Indexed: 12/19/2022]
Abstract
Currently, increasing demand of biochemicals produced from renewable resources has motivated researchers to seek microbial production strategies instead of traditional chemical methods. As a microbial platform, Bacillus subtilis possesses many advantages including the generally recognized safe status, clear metabolic networks, short growth cycle, mature genetic editing methods and efficient protein secretion systems. Engineered B. subtilis strains are being increasingly used in laboratory research and in industry for the production of valuable proteins and other chemicals. In this review, we first describe the recent advances of bioinformatics strategies during the research and applications of B. subtilis. Secondly, the applications of B. subtilis in enzymes and recombinant proteins production are summarized. Further, the recent progress in employing metabolic engineering and synthetic biology strategies in B. subtilis platform strain to produce commodity chemicals is systematically introduced and compared. Finally, the major limitations for the further development of B. subtilis platform strain and possible future directions for its research are also discussed.
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Ben‐David Y, Moraïs S, Bayer EA, Mizrahi I. Rapid adaptation for fibre degradation by changes in plasmid stoichiometry within Lactobacillus plantarum at the synthetic community level. Microb Biotechnol 2020; 13:1748-1764. [PMID: 32639625 PMCID: PMC7533337 DOI: 10.1111/1751-7915.13584] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 04/11/2020] [Accepted: 04/12/2020] [Indexed: 12/19/2022] Open
Abstract
The multi-enzyme cellulosome complex can mediate the valorization of lignocellulosic biomass into soluble sugars that can serve in the production of biofuels and valuable products. A potent bacterial chassis for the production of active cellulosomes displayed on the cell surface is the bacterium Lactobacillus plantarum, a lactic acid bacterium used in many applications. Here, we developed a methodological pipeline to produce improved designer cellulosomes, using a cell-consortium approach, whereby the different components self-assemble on the surface of L. plantarum. The pipeline served as a vehicle to select and optimize the secretion efficiency of potent designer cellulosome enzyme components, to screen for the most efficient enzymatic combinations and to assess attempts to grow the engineered bacterial cells on wheat straw as a sole carbon source. Using this strategy, we were able to improve the secretion efficiency of the selected enzymes and to secrete a fully functional high-molecular-weight scaffoldin component. The adaptive laboratory process served to increase significantly the enzymatic activity of the most efficient cell consortium. Internal plasmid re-arrangement towards a higher enzymatic performance attested for the suitability of the approach, which suggests that this strategy represents an efficient way for microbes to adapt to changing conditions.
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Affiliation(s)
- Yonit Ben‐David
- Department of Biomolecular SciencesThe Weizmann Institute of ScienceRehovot7610001Israel
| | - Sarah Moraïs
- Department of Biomolecular SciencesThe Weizmann Institute of ScienceRehovot7610001Israel
- Department of Life SciencesNational Institute for Biotechnology in the NegevBen‐Gurion University of the NegevBeer‐Sheva8499000Israel
| | - Edward A. Bayer
- Department of Biomolecular SciencesThe Weizmann Institute of ScienceRehovot7610001Israel
| | - Itzhak Mizrahi
- Department of Life SciencesNational Institute for Biotechnology in the NegevBen‐Gurion University of the NegevBeer‐Sheva8499000Israel
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9
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Averesch NJH, Rothschild LJ. Metabolic engineering of Bacillus subtilis for production of para-aminobenzoic acid - unexpected importance of carbon source is an advantage for space application. Microb Biotechnol 2019; 12:703-714. [PMID: 30980511 PMCID: PMC6559200 DOI: 10.1111/1751-7915.13403] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/08/2019] [Accepted: 03/08/2019] [Indexed: 01/28/2023] Open
Abstract
High-strength polymers, such as aramid fibres, are important materials in space technology. To obtain these materials in remote locations, such as Mars, biological production is of interest. The aromatic polymer precursor para-aminobenzoic acid (pABA) can be derived from the shikimate pathway through metabolic engineering of Bacillus subtilis, an organism suited for space synthetic biology. Our engineering strategy included repair of the defective indole-3-glycerol phosphate synthase (trpC), knockout of one chorismate mutase isozyme (aroH) and overexpression of the aminodeoxychorismate synthase (pabAB) and aminodeoxychorismate lyase (pabC) from the bacteria Corynebacterium callunae and Xenorhabdus bovienii respectively. Further, a fusion-protein enzyme (pabABC) was created for channelling of the carbon flux. Using adaptive evolution, mutants of the production strain, able to metabolize xylose, were created, to explore and compare pABA production capacity from different carbon sources. Rather than the efficiency of the substrate or performance of the biochemical pathway, the product toxicity, which was strongly dependent on the pH, appeared to be the overall limiting factor. The highest titre achieved in shake flasks was 3.22 g l-1 with a carbon yield of 12.4% [C-mol/C-mol] from an amino sugar. This promises suitability of the system for in situ resource utilization (ISRU) in space biotechnology, where feedstocks that can be derived from cyanobacterial cell lysate play a role.
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Affiliation(s)
- Nils J. H. Averesch
- Universities Space Research AssociationMountain ViewCA94043USA
- NASA Ames Research CenterMoffett FieldCA94035USA
- Present address:
Stanford UniversityStanfordCA94305USA
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10
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Abstract
Production of fuels and chemicals from renewable lignocellulosic feedstocks is a promising alternative to petroleum-derived compounds. Due to the complexity of lignocellulosic feedstocks, microbial conversion of all potential substrates will require substantial metabolic engineering. Non-model microbes offer desirable physiological traits, but also increase the difficulty of heterologous pathway engineering and optimization. The development of modular design principles that allow metabolic pathways to be used in a variety of novel microbes with minimal strain-specific optimization will enable the rapid construction of microbes for commercial production of biofuels and bioproducts. In this review, we discuss variability of lignocellulosic feedstocks, pathways for catabolism of lignocellulose-derived compounds, challenges to heterologous engineering of catabolic pathways, and opportunities to apply modular pathway design. Implementation of these approaches will simplify the process of modifying non-model microbes to convert diverse lignocellulosic feedstocks.
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11
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He X, Xue T, Ma Y, Zhang J, Wang Z, Hong J, Hui L, Qiao J, Song H, Zhang M. Identification of functional butanol-tolerant genes from Escherichia coli mutants derived from error-prone PCR-based whole-genome shuffling. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:73. [PMID: 30976323 PMCID: PMC6442406 DOI: 10.1186/s13068-019-1405-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 03/12/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Butanol is an important biofuel and chemical. The development of butanol-tolerant strains and the identification of functional butanol-tolerant genes is essential for high-yield bio-butanol production due to the toxicity of butanol. RESULTS Escherichia coli BW25113 was subjected for the first time to error-prone PCR-based whole-genome shuffling. The resulting mutants BW1847 and BW1857 were found to tolerate 2% (v/v) butanol and short-chain alcohols, including ethanol, isobutanol, and 1-pentanol. The mutants exhibited good stability under butanol stress, indicating that they are potential host strains for the construction of butanol pathways. BW1847 had better butanol tolerance than BW1857 under 0-0.75% (v/v) butanol stress, but showed a lower tolerance than BW1857 under 1.25-2% (v/v) butanol stress. Genome resequencing and PCR confirmation revealed that BW1847 and BW1857 had nine and seven single nucleotide polymorphisms, respectively, and a common 14-kb deletion. Functional complementation experiments of the SNPs and deleted genes demonstrated that the mutations of acrB and rob gene and the deletion of TqsA increased the tolerance of the two mutants to butanol. Genome-wide site-specific mutated strains DT385 (acrB C1198T) and DT900 (rob AT686-7) also showed significant tolerance to butanol and had higher butanol efflux ability than the control, further demonstrating that their mutations yield an inactive protein that enhances butanol resistance characteristics. CONCLUSIONS Stable E. coli mutants with enhanced short alcohols and high concentrations of butanol tolerance were obtained through a rapid and effective method. The key genes of butanol tolerance in the two mutants were identified by comparative functional genomic analysis.
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Affiliation(s)
- Xueting He
- Biomass Conversion Laboratory, R&D Center for Petrochemical Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Tingli Xue
- Biomass Conversion Laboratory, R&D Center for Petrochemical Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Yuanyuan Ma
- Biomass Conversion Laboratory, R&D Center for Petrochemical Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
- Frontier Technology Research Institute, Tianjin University, Tianjin, 30072 People’s Republic of China
- Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin), Tianjin, 300072 China
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Tianjin University, Tianjin, 300072 China
| | - Junyan Zhang
- Biomass Conversion Laboratory, R&D Center for Petrochemical Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Zhiquan Wang
- Biomass Conversion Laboratory, R&D Center for Petrochemical Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Jiefang Hong
- Biomass Conversion Laboratory, R&D Center for Petrochemical Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
| | - Lanfeng Hui
- Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science and Technology, Tianjin, 300457 China
| | - Jianjun Qiao
- Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin), Tianjin, 300072 China
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Tianjin University, Tianjin, 300072 China
| | - Hao Song
- Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin), Tianjin, 300072 China
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Tianjin University, Tianjin, 300072 China
| | - Minhua Zhang
- Biomass Conversion Laboratory, R&D Center for Petrochemical Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
- Frontier Technology Research Institute, Tianjin University, Tianjin, 30072 People’s Republic of China
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12
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Jia X, Kelly RM, Han Y. Simultaneous biosynthesis of ( R)-acetoin and ethylene glycol from D-xylose through in vitro metabolic engineering. Metab Eng Commun 2018; 7:e00074. [PMID: 30197863 PMCID: PMC6127078 DOI: 10.1016/j.mec.2018.e00074] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 06/18/2018] [Accepted: 06/24/2018] [Indexed: 11/28/2022] Open
Abstract
(R)-acetoin is a four-carbon platform compound used as the precursor for synthesizing novel optically active materials. Ethylene glycol (EG) is a large-volume two-carbon commodity chemical used as the anti-freezing agent and building-block molecule for various polymers. Currently established microbial fermentation processes for converting monosaccharides to either (R)-acetoin or EG are plagued by the formation of undesirable by-products. We show here that a cell-free bioreaction scheme can generate enantiomerically pure acetoin and EG as co-products from biomass-derived D-xylose. The seven-step, ATP-free system included in situ cofactor regeneration and recruited enzymes from Escherichia coli W3110, Bacillus subtilis shaijiu 32 and Caulobacter crescentus CB 2. Optimized in vitro biocatalytic conditions generated 3.2 mM (R)-acetoin with stereoisomeric purity of 99.5% from 10 mM D-xylose at 30 °C and pH 7.5 after 24 h, with an initial (R)-acetoin productivity of 1.0 mM/h. Concomitantly, EG was produced at 5.5 mM, with an initial productivity of 1.7 mM/h. This in vitro biocatalytic platform illustrates the potential for production of multiple value-added biomolecules from biomass-based sugars with no ATP requirement.
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Key Words
- (R)-acetoin
- BSA, bovine serum albumin
- Cofactor regeneration
- D-xylose
- EG, ethylene glycol
- EMP, Embden-Meyerhoff-Parnas
- Ethylene glycol
- FAD, flavin adenine dinucleotide
- GC, gas chromatography
- HPLC, high-pressure liquid chromatography
- IPTG, isopropyl-β-D-thiogalactopyranoside
- In vitro metabolic engineering
- LB, lysogeny broth
- NAD+, oxidized nicotinamide adenine dinucleotide
- NADH, reduced nicotinamide adenine dinucleotide
- PET, polyethylene terephthalate
- PP, pentose phosphate
- SDS-PAGE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis
- ThDP, Thiamine diphosphate
- ee, enantiomeric excess
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Affiliation(s)
- Xiaojing Jia
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Robert M. Kelly
- Department of Chemical and Biomolecular Engineering North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Yejun Han
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
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13
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Fan X, Wu H, Jia Z, Li G, Li Q, Chen N, Xie X. Metabolic engineering of Bacillus subtilis for the co-production of uridine and acetoin. Appl Microbiol Biotechnol 2018; 102:8753-8762. [DOI: 10.1007/s00253-018-9316-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 07/31/2018] [Accepted: 08/08/2018] [Indexed: 01/19/2023]
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14
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Liu D, Mao Z, Guo J, Wei L, Ma H, Tang Y, Chen T, Wang Z, Zhao X. Construction, Model-Based Analysis, and Characterization of a Promoter Library for Fine-Tuned Gene Expression in Bacillus subtilis. ACS Synth Biol 2018; 7:1785-1797. [PMID: 29944832 DOI: 10.1021/acssynbio.8b00115] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Promoters are among the most-important and most-basic tools for the control of metabolic pathways. However, previous research mainly focused on the screening and characterization of some native promoters in Bacillus subtilis. To develop a broadly applicable promoter system for this important platform organism, we created a de novo synthetic promoter library (SPL) based on consensus sequences by analyzing the microarray transcriptome data of B. subtilis 168. A total of 214 potential promoters spanning a gradient of strengths was isolated and characterized by a green fluorescence assay. Among these, a detailed intensity analysis was conducted on nine promoters with different strengths by reverse-transcription polymerase chain reaction (RT-PCR) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Furthermore, reconstructed promoters and promoter cassettes (tandem promoter cluster) were designed via statistical model-based analysis and tandem dual promoters, which showed strength that was increased 1.2- and 2.77-fold compared to that of promoter P43, respectively. Finally, the SPL was employed in the production of inosine and acetoin by repressing and over-expressing the relevant metabolic pathways, yielding a 700% and 44% increase relative to the respective control strains. This is the first report of a de novo synthetic promoter library for B. subtilis, which is independent of any native promoter. The strategy of improving and fine-tuning promoter strengths will contribute to future metabolic engineering and synthetic biology projects in B. subtilis.
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Affiliation(s)
| | - Zhitao Mao
- Key Laboratory of System Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | | | | | - Hongwu Ma
- Key Laboratory of System Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yajie Tang
- Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei Key Laboratory of Industrial Microbiology, Hubei Provincial Cooperative Innovation Center of Industrial Fermentation, Hubei University of Technology, Wuhan 430068, China
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15
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Integrated whole-genome and transcriptome sequence analysis reveals the genetic characteristics of a riboflavin-overproducing Bacillus subtilis. Metab Eng 2018; 48:138-149. [DOI: 10.1016/j.ymben.2018.05.022] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 05/17/2018] [Accepted: 05/31/2018] [Indexed: 11/23/2022]
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16
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Mandlaa, Sun Z, Wang R, Han X, Xu H, Yang W. Enhanced 2-keto-L-gulonic acid production by applying L-sorbose-tolerant helper strain in the co-culture system. AMB Express 2018; 8:30. [PMID: 29492704 PMCID: PMC5833332 DOI: 10.1186/s13568-018-0562-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 02/22/2018] [Indexed: 11/21/2022] Open
Abstract
2-Keto-L-gulonic acid (the precursor of vitamin C) is bio-converted from L-sorbose by mixed fermentation of Ketogulonicigenium vulgare and a helper strain. The helper strain promotes the conversion of 2-KLG by enhancing the growth of K. vulgare, but its growth is greatly inhibited by high concentration of L-sorbose, which consequently influence the 2-KLG production. The aim of this study is to obtain L-sorbose-tolerant helper strain (LHS) by experimental evolution for reduced L-sorbose-inhibition-effect and enhanced 2-KLG productivity in high concentration of L-sorbose. After three steps screening by using our devised screening strategy, three strains (i.e., Bc 21, Bc 47, Bc 50) with high resistance to high concentration of L-sorbose were obtained. The fermentation tests by co-culturing Bc 21 and K. vulgare 418 showed that the production of 2-KLG was increased by 17.9% in 11% L-sorbose medium than that in 8% after 55 h of fermentation and the conversion rate was 89.5%. The results suggested that Bc 21 could be an ideal helper strain for 2-KLG production under high concentration of L-sorbose and demonstrated the feasibility of using experimental evolution to breed LHS for vitamin C production.
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Affiliation(s)
- Mandlaa
- College of Food Science and Engineering, Inner Mongolia Agricultural University, 010018 Hohhot, China
- Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, 110016 Shenyang, China
| | - Ziyu Sun
- College of Food Science and Engineering, Inner Mongolia Agricultural University, 010018 Hohhot, China
| | - Ruigang Wang
- College of Life Science, Inner Mongolia Agricultural University, 010018 Hohhot, China
| | - Xiaodong Han
- College of Life Science, Inner Mongolia Agricultural University, 010018 Hohhot, China
| | - Hui Xu
- Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, 110016 Shenyang, China
| | - Weichao Yang
- Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, 110016 Shenyang, China
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17
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Zhou X, Zhou X, Zhang H, Cao R, Xu Y. Improving the performance of cell biocatalysis and the productivity of acetoin from 2,3-butanediol using a compressed oxygen supply. Process Biochem 2018. [DOI: 10.1016/j.procbio.2017.09.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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18
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Liu Y, Li J, Du G, Chen J, Liu L. Metabolic engineering of Bacillus subtilis fueled by systems biology: Recent advances and future directions. Biotechnol Adv 2017; 35:20-30. [DOI: 10.1016/j.biotechadv.2016.11.003] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/21/2016] [Accepted: 11/16/2016] [Indexed: 12/25/2022]
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19
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Chen J, Zhu Y, Fu G, Song Y, Jin Z, Sun Y, Zhang D. High-level intra- and extra-cellular production of d-psicose 3-epimerase via a modified xylose-inducible expression system in Bacillus subtilis. ACTA ACUST UNITED AC 2016; 43:1577-1591. [DOI: 10.1007/s10295-016-1819-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 07/30/2016] [Indexed: 01/22/2023]
Abstract
Abstract
d-Psicose 3-epimerase (DPEase) converts d-fructose into d-psicose which exists in nature in limited quantities and has key physiological functions. In this study, RDPE (DPEase from Ruminococcus sp. 5_1_39BFAA) was successfully constitutively expressed in Bacillus subtilis, which is the first report of its kind. Three sugar-inducible promoters were compared, and the xylose-inducible promoter PxylA was proved to be the most efficient for RDPE production. Based on the analysis of the inducer concentration and RDPE expression, we surmised that there was an extremely close correlation between the intracellular RDPE expression and xylose accumulation level. Subsequently, after the metabolic pathway of xylose was blocked by deletion of xylAB, the intra- and extra-cellular RDPE expression was significantly enhanced. Meanwhile, the optimal xylose induction concentration was reduced from 4.0 to 0.5 %. Eventually, the secretion level of RDPE reached 95 U/mL and 2.6 g/L in a 7.5-L fermentor with the fed-batch fermentation, which is the highest production of DPEase by a microbe to date.
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Affiliation(s)
- Jingqi Chen
- grid.458513.e 0000000417633963 Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences 300308 Tianjin People’s Republic of China
- grid.9227.e 0000000119573309 Key Laboratory of Systems Microbial Biotechnology Chinese Academy of Sciences 300308 Tianjin People’s Republic of China
| | - Yueming Zhu
- grid.458513.e 0000000417633963 Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences 300308 Tianjin People’s Republic of China
- National Engineering Laboratory for Industrial Enzymes 300308 Tianjin People’s Republic of China
| | - Gang Fu
- grid.458513.e 0000000417633963 Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences 300308 Tianjin People’s Republic of China
- National Engineering Laboratory for Industrial Enzymes 300308 Tianjin People’s Republic of China
| | - Yafeng Song
- grid.458513.e 0000000417633963 Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences 300308 Tianjin People’s Republic of China
- grid.9227.e 0000000119573309 Key Laboratory of Systems Microbial Biotechnology Chinese Academy of Sciences 300308 Tianjin People’s Republic of China
| | - Zhaoxia Jin
- grid.440692.d School of Biological Engineering Dalian Polytechnic University 116034 Dalian People’s Republic of China
| | - Yuanxia Sun
- grid.458513.e 0000000417633963 Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences 300308 Tianjin People’s Republic of China
- National Engineering Laboratory for Industrial Enzymes 300308 Tianjin People’s Republic of China
| | - Dawei Zhang
- grid.458513.e 0000000417633963 Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences 300308 Tianjin People’s Republic of China
- grid.9227.e 0000000119573309 Key Laboratory of Systems Microbial Biotechnology Chinese Academy of Sciences 300308 Tianjin People’s Republic of China
- National Engineering Laboratory for Industrial Enzymes 300308 Tianjin People’s Republic of China
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20
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Zhang B, Li XL, Fu J, Li N, Wang Z, Tang YJ, Chen T. Production of Acetoin through Simultaneous Utilization of Glucose, Xylose, and Arabinose by Engineered Bacillus subtilis. PLoS One 2016; 11:e0159298. [PMID: 27467131 PMCID: PMC4965033 DOI: 10.1371/journal.pone.0159298] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Accepted: 06/30/2016] [Indexed: 12/11/2022] Open
Abstract
Glucose, xylose and arabinose are the three most abundant monosaccharide found in lignocellulosic biomass. Effectively and simultaneously utilization of these sugars by microorganisms for production of the biofuels and bio-chemicals is essential toward directly fermentation of the lignocellulosic biomass. In our previous study, the recombinant Bacillus subtilis 168ARSRCPΔacoAΔbdhA strain was already shown to efficiently utilize xylose for production of acetoin, with a yield of 0.36 g/g xylose. In the current study, the Bacillus subtilis168ARSRCPΔacoAΔbdhA strain was further engineered to produce acetoin from a glucose, xylose, and arabinose mixtures. To accomplish this, the endogenous xylose transport protein AraE, the exogenous xylose isomerase gene xylA and the xylulokinase gene xylB from E. coli were co-overexpressed in the Bacillus subtilis 168ARSRCPΔacoAΔbdhA strain, which enabled the resulting strain, denoted ZB02, to simultaneously utilize glucose and xylose. Unexpectedly, the ZB02 strain could simultaneously utilize glucose and arabinose also. Further results indicated that the transcriptional inhibition of the arabinose transport protein gene araE was the main limiting factor for arabinose utilization in the presence of glucose. Additionally, the arabinose operon in B. subtilis could be activated by the addition of arabinose, even in the presence of glucose. Through fed-batch fermentation, strain ZB02 could simultaneously utilize glucose, xylose, and arabinose, with an average sugar consumption rate of 3.00 g/l/h and an average production of 62.2 g/l acetoin at a rate of 0.864 g/l/h. Finally, the strain produced 11.2 g/l acetoin from lignocellulosic hydrolysate (containing 20.6g/l glucose, 12.1 g/l xylose and 0.45 g/l arabinose) in flask cultivation, with an acetoin yield of 0.34 g/g total sugar. The result demonstrates that this strain has good potential for the utilization of lignocellulosic hydrolysate for production of acetoin.
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Affiliation(s)
- Bo Zhang
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Xin-li Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Jing Fu
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Ning Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Zhiwen Wang
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- * E-mail: (TC); (ZW)
| | - Ya-jie Tang
- Hubei Provincial Cooperative Innovation Center of Industrial Fermentation; Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei University of Technology, Wuhan, China
| | - Tao Chen
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Hubei Provincial Cooperative Innovation Center of Industrial Fermentation; Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei University of Technology, Wuhan, China
- * E-mail: (TC); (ZW)
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21
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2,3-Butanediol production from cellobiose using exogenous beta-glucosidase-expressing Bacillus subtilis. Appl Microbiol Biotechnol 2016; 100:5781-9. [DOI: 10.1007/s00253-016-7326-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 01/12/2016] [Accepted: 01/14/2016] [Indexed: 01/04/2023]
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22
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Biofuels and bio-based chemicals from lignocellulose: metabolic engineering strategies in strain development. Biotechnol Lett 2015; 38:213-21. [PMID: 26466596 DOI: 10.1007/s10529-015-1976-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 10/07/2015] [Indexed: 12/22/2022]
Abstract
Interest in developing a sustainable technology for fuels and chemicals has unleashed tremendous creativity in metabolic engineering for strain development over the last few years. This is driven by the exceptionally recalcitrant substrate, lignocellulose, and the necessity to keep the costs down for commodity products. Traditional methods of gene expression and evolutionary engineering are more effectively used with the help of synthetic biology and -omics techniques. Compared to the last biomass research peak during the 1980s oil crisis, a more diverse range of microorganisms are being engineered for a greater variety of products, reflecting the broad applicability and effectiveness of today's gene technology. We review here several prominent and successful metabolic engineering strategies with emphasis on the following four areas: xylose catabolism, inhibitor tolerance, synthetic microbial consortium, and cellulosic oligomer assimilation.
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23
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Tang B, Lei P, Xu Z, Jiang Y, Xu Z, Liang J, Feng X, Xu H. Highly efficient rice straw utilization for poly-(γ-glutamic acid) production by Bacillus subtilis NX-2. BIORESOURCE TECHNOLOGY 2015; 193:370-6. [PMID: 26143572 DOI: 10.1016/j.biortech.2015.05.110] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 05/27/2015] [Accepted: 05/28/2015] [Indexed: 05/08/2023]
Abstract
Lignocellulosic biomass has been identified as an economic and environmental feedstock for future biotechnological production. Here, for the first time, poly-(γ-glutamic acid) (PGA) production by Bacillus subtilis NX-2 using rice straw is investigated. Based on two-stage hydrolysis and characteristic consumption of xylose and glucose by B. subtilis NX-2, a co-fermentation strategy was designed to better accumulate PGA in a 7.5L fermentor by two feeding methods. The maximum cumulative respective PGA production and PGA productivity were 73.0 ± 0.5 g L(-1) and 0.81 g L(-1) h(-1) by the continuous feeding method, with carbon source cost was saved by 84.2% and 42.5% compared with glucose and cane molasse, respectively. These results suggest that rice straw, a type of abundant, low-cost, non-food lignocellulosic feedstock, may be feasibly and efficiently utilized for industrial-scale production of PGA.
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Affiliation(s)
- Bao Tang
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Peng Lei
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Zongqi Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Yongxiang Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Zheng Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Jinfeng Liang
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Xiaohai Feng
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Hong Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
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