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Liu J, Zhang Q, Liang X, Zhang R, Huang X, Zhang S, Xie Z, Gao W, Liu H. Improving glucose oxidase catalysis in Aspergillus niger via Vitreoscilla hemoglobin fusion protein. Appl Microbiol Biotechnol 2024; 108:48. [PMID: 38183481 DOI: 10.1007/s00253-023-12931-4] [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: 08/06/2023] [Revised: 10/17/2023] [Accepted: 10/27/2023] [Indexed: 01/08/2024]
Abstract
Oxygen is crucial for converting glucose to gluconic acid catalyzed by glucose oxidase (Gox). However, industrial gluconic acid production faces oxygen supply limitations. To enhance Gox efficiency, Vitreoscilla hemoglobin (VHb) has been considered as an efficient oxygen transfer carrier. This study identified GoxA, a specific isoform of Gox in the industrial gluconic acid-producing strain of Aspergillus niger. Various forms of VHb expression in A. niger were tested to improve GoxA's catalytic efficiency. Surprisingly, the expression of free VHb, both intracellularly and extracellularly, did not promote gluconic acid production during shake flask fermentation. Then, five fusion proteins were constructed by linking Gox and VHb using various methods. Among these, VHb-GS1-GoxA, where VHb's C-terminus connected to GoxA's N-terminus via the flexible linker GS1, demonstrated a significantly higher Kcat/Km value (96% higher) than GoxA. Unfortunately, the expression of VHb-GS1-GoxA in A. niger was limited, resulting in a low gluconic acid production of 3.0 g/L. To overcome the low expression problem, single- and dual-strain systems were designed with tools of SpyCatcher/SpyTag and SnoopCatcher/SnoopTag. In these systems, Gox and VHb were separately expressed and then self-assembled into complex proteins. Impressively, the single-strain system outperformed the GoxA overexpression strain S1971, resulting in 23% and 9% higher gluconic acid production under 0.6 vvm and 1.2 vvm aeration conditions in the bioreactor fermentation, respectively. The successful construction of Gox and VHb fusion or complex proteins, as proposed in this study, presents promising approaches to enhance Gox catalytic efficiency and lower aerodynamic costs in gluconic acid production. KEY POINTS: • Overexpressing free VHb in A. niger did not improve the catalytic efficiency of Gox • The VHb-GS1-GoxA showed an increased Kcat/Km value by 96% than GoxA • The single-strain system worked better in the gluconic acid bioreactor fermentation.
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Affiliation(s)
- Jiao Liu
- MOE Key Laboratory of Industrial Fermentation Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China
- Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Qian Zhang
- MOE Key Laboratory of Industrial Fermentation Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Xingying Liang
- MOE Key Laboratory of Industrial Fermentation Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Rong Zhang
- MOE Key Laboratory of Industrial Fermentation Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Xiaojie Huang
- MOE Key Laboratory of Industrial Fermentation Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China
- Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Shanshan Zhang
- MOE Key Laboratory of Industrial Fermentation Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China
- Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Zhoujie Xie
- MOE Key Laboratory of Industrial Fermentation Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China
- Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Weixia Gao
- MOE Key Laboratory of Industrial Fermentation Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China
- Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Hao Liu
- MOE Key Laboratory of Industrial Fermentation Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China.
- Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, Tianjin University of Science & Technology, Tianjin, 300457, China.
- National Technology Innovation Center of Synthetic Biology, Tianjin, 300308, People's Republic of China.
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Santin A, Spatola Rossi T, Morlino MS, Gupte AP, Favaro L, Morosinotto T, Treu L, Campanaro S. Autotrophic poly-3-hydroxybutyrate accumulation in Cupriavidus necator for sustainable bioplastic production triggered by nutrient starvation. BIORESOURCE TECHNOLOGY 2024; 406:131068. [PMID: 38972429 DOI: 10.1016/j.biortech.2024.131068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Revised: 07/03/2024] [Accepted: 07/03/2024] [Indexed: 07/09/2024]
Abstract
Cupriavidus necator is a facultative chemolithoautotrophic bacterium able to convert carbon dioxide into poly-3-hydroxybutyrate. This is highly promising as the conversion process allows the production of sustainable and biodegradable plastics. Poly-3-hydroxybutyrate accumulation is known to be induced by nutrient starvation, but information regarding the optimal stress conditions controlling the process is still heterogeneous and fragmentary. This study presents a comprehensive comparison of the effects of nutrient stress conditions, namely nitrogen, hydrogen, phosphorus, oxygen, and magnesium deprivation, on poly-3-hydroxybutyrate accumulation in C. necator DSM545. Nitrogen starvation exhibited the highest poly-3-hydroxybutyrate accumulation, achieving 54% of total cell dry weight after four days of nutrient stress, and a carbon conversion efficiency of 85%. The gas consumption patterns indicated flexible physiological mechanisms underlying polymer accumulation and depolymerization. These findings provide insights into strategies for efficient carbon conversion into bioplastics, and highlight the key role of C. necator for future industrial-scale applications.
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Affiliation(s)
- Anna Santin
- Department of Biology, University of Padova, 35131 Padova, Italy.
| | | | | | - Ameya Pankaj Gupte
- Waste to Bioproducts Lab, Department of Agronomy Food Natural Resources Animals and Environment, University of Padova - Agripolis, 35020 Legnaro PD, Italy.
| | - Lorenzo Favaro
- Waste to Bioproducts Lab, Department of Agronomy Food Natural Resources Animals and Environment, University of Padova - Agripolis, 35020 Legnaro PD, Italy; Department of Microbiology, Stellenbosch University, Private Bag X1, 7602 Matieland, South Africa.
| | | | - Laura Treu
- Department of Biology, University of Padova, 35131 Padova, Italy.
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3
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Fukala I, Kučera I. Natural Polyhydroxyalkanoates-An Overview of Bacterial Production Methods. Molecules 2024; 29:2293. [PMID: 38792154 PMCID: PMC11124392 DOI: 10.3390/molecules29102293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 05/05/2024] [Accepted: 05/10/2024] [Indexed: 05/26/2024] Open
Abstract
Polyhydroxyalkanoates (PHAs) are intracellular biopolymers that microorganisms use for energy and carbon storage. They are mechanically similar to petrochemical plastics when chemically extracted, but are completely biodegradable. While they have potential as a replacement for petrochemical plastics, their high production cost using traditional carbon sources remains a significant challenge. One potential solution is to modify heterotrophic PHA-producing strains to utilize alternative carbon sources. An alternative approach is to utilize methylotrophic or autotrophic strains. This article provides an overview of bacterial strains employed for PHA production, with a particular focus on those exhibiting the highest PHA content in dry cell mass. The strains are organized according to their carbon source utilization, encompassing autotrophy (utilizing CO2, CO) and methylotrophy (utilizing reduced single-carbon substrates) to heterotrophy (utilizing more traditional and alternative substrates).
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Affiliation(s)
| | - Igor Kučera
- Department of Biochemistry, Faculty of Science, Masaryk University, Kotlářská 267/2, CZ-61137 Brno, Czech Republic;
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Wu F, Wang S, Zhou D, Gao S, Song G, Liang Y, Wang Q. Metabolic engineering of Escherichia coli for high-level production of the biodegradable polyester monomer 2-pyrone-4,6-dicarboxylic acid. Metab Eng 2024; 83:52-60. [PMID: 38521489 DOI: 10.1016/j.ymben.2024.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 03/15/2024] [Accepted: 03/15/2024] [Indexed: 03/25/2024]
Abstract
2-Pyrone-4,6-dicarboxylic acid (PDC), a chemically stable pseudo-aromatic dicarboxylic acid, is a promising building block compound for manufacturing biodegradable polyesters. This study aimed to construct high-performance cell factories enabling the efficient production of PDC from glucose. Firstly, the effective enzymes of the PDC biosynthetic pathway were overexpressed on the chromosome of the 3-dehydroshikimate overproducing strain. Consequently, the one-step biosynthesis of PDC from glucose was achieved. Further, the PDC production was enhanced by multi-copy integration of the key gene PsligC encoding 4-carboxy-2-hydroxymuconate-6-semialdehyde dehydrogenase and co-expression of Vitreoscilla hemoglobin. Subsequently, the PDC production was substantially improved by redistributing the metabolic flux for cell growth and PDC biosynthesis based on dynamically downregulating the expression of pyruvate kinase. The resultant strain PDC50 produced 129.37 g/L PDC from glucose within 78 h under fed-batch fermentation conditions, with a yield of 0.528 mol/mol and an average productivity of 1.65 g/L/h. The findings of this study lay the foundation for the potential industrial production of PDC.
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Affiliation(s)
- Fengli Wu
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308, China.
| | - Shucai Wang
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308, China; College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China
| | - Dan Zhou
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308, China; College of Bioengineering, Chongqing University, Chongqing, 400030, China
| | - Shukai Gao
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308, China
| | - Guotian Song
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308, China
| | - Yanxia Liang
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308, China
| | - Qinhong Wang
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China; National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308, China.
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5
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Jang Y, Lee YJ, Gong G, Lee SM, Um Y, Kim KH, Ko JK. Carbon dioxide valorization into resveratrol via lithoautotrophic fermentation using engineered Cupriavidus necator H16. Microb Cell Fact 2024; 23:122. [PMID: 38678199 PMCID: PMC11055273 DOI: 10.1186/s12934-024-02398-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 04/19/2024] [Indexed: 04/29/2024] Open
Abstract
BACKGROUND Industrial biomanufacturing of value-added products using CO2 as a carbon source is considered more sustainable, cost-effective and resource-efficient than using common carbohydrate feedstocks. Cupriavidus necator H16 is a representative H2-oxidizing lithoautotrophic bacterium that can be utilized to valorize CO2 into valuable chemicals and has recently gained much attention as a promising platform host for versatile C1-based biomanufacturing. Since this microbial platform is genetically tractable and has a high-flux carbon storage pathway, it has been engineered to produce a variety of valuable compounds from renewable carbon sources. In this study, the bacterium was engineered to produce resveratrol autotrophically using an artificial phenylpropanoid pathway. RESULTS The heterologous genes involved in the resveratrol biosynthetic pathway-tyrosine ammonia lyase (TAL), 4-coumaroyl CoA ligase (4CL), and stilbene synthase (STS) -were implemented in C. necator H16. The overexpression of acetyl-CoA carboxylase (ACC), disruption of the PHB synthetic pathway, and an increase in the copy number of STS genes enhanced resveratrol production. In particular, the increased copies of VvSTS derived from Vitis vinifera resulted a 2-fold improvement in resveratrol synthesis from fructose. The final engineered CR-5 strain produced 1.9 mg/L of resveratrol from CO2 and tyrosine via lithoautotrophic fermentation. CONCLUSIONS To the best of our knowledge, this study is the first to describe the valorization of CO2 into polyphenolic compounds by engineering a phenylpropanoid pathway using the lithoautotrophic bacterium C. necator H16, demonstrating the potential of this strain a platform for sustainable chemical production.
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Affiliation(s)
- Yongjae Jang
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Yeon Ji Lee
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Gyeongtaek Gong
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
- Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul, 02792, Republic of Korea
| | - Sun-Mi Lee
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
- Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul, 02792, Republic of Korea
| | - Youngsoon Um
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
- Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul, 02792, Republic of Korea
| | - Kyoung Heon Kim
- Department of Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Ja Kyong Ko
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.
- Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul, 02792, Republic of Korea.
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6
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Wang Z, Pan H, Ni S, Li Z, Lian J. Establishing CRISPRi for Programmable Gene Repression and Genome Evolution in Cupriavidus necator. ACS Synth Biol 2024; 13:851-861. [PMID: 38350870 DOI: 10.1021/acssynbio.3c00664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2024]
Abstract
Cupriavidus necator H16 is a "Knallgas" bacterium with the ability to utilize various carbon sources and has been employed as a versatile microbial cell factory to produce a wide range of value-added compounds. However, limited genome engineering, especially gene regulation methods, has constrained its full potential as a microbial production platform. The advent of CRISPR/Cas9 technology has shown promise in addressing this limitation. Here, we developed an optimized CRISPR interference (CRISPRi) system for gene repression in C. necator by expressing a codon-optimized deactivated Cas9 (dCas9) and appropriate single guide RNAs (sgRNAs). CRISPRi was proven to be a programmable and controllable tool and could successfully repress both exogenous and endogenous genes. As a case study, we decreased the accumulation of polyhydroxyalkanoate (PHB) via CRISPRi and rewired the carbon fluxes to the synthesis of lycopene. Additionally, by disturbing the expression of DNA mismatch repair gene mutS with CRISPRi, we established CRISPRi-Mutator for genome evolution, rapidly generating mutant strains with enhanced hydrogen peroxide tolerance and robustness in microbial electrosynthesis (MES) system. Our work provides an efficient CRISPRi toolkit for advanced genetic manipulation and optimization of C. necator cell factories for diverse biotechnology applications.
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Affiliation(s)
- Zhijiao Wang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education & National Key Laboratory of Biobased Transportation Fuel Technology, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
- ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 310000, China
| | - Haojie Pan
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education & National Key Laboratory of Biobased Transportation Fuel Technology, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
- ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 310000, China
| | - Sulin Ni
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education & National Key Laboratory of Biobased Transportation Fuel Technology, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Zhongjian Li
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education & National Key Laboratory of Biobased Transportation Fuel Technology, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jiazhang Lian
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education & National Key Laboratory of Biobased Transportation Fuel Technology, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
- ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 310000, China
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7
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Chen Z, Wu T, Yu S, Li M, Fan X, Huo YX. Self-assembly systems to troubleshoot metabolic engineering challenges. Trends Biotechnol 2024; 42:43-60. [PMID: 37451946 DOI: 10.1016/j.tibtech.2023.06.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 06/18/2023] [Accepted: 06/23/2023] [Indexed: 07/18/2023]
Abstract
Enzyme self-assembly is a technology in which enzyme units can aggregate into ordered macromolecules, assisted by scaffolds. In metabolic engineering, self-assembly strategies have been explored for aggregating multiple enzymes in the same pathway to improve sequential catalytic efficiency, which in turn enables high-level production. The performance of the scaffolds is critical to the formation of an efficient and stable assembly system. This review comprehensively analyzes these scaffolds by exploring how they assemble, and it illustrates how to apply self-assembly strategies for different modules in metabolic engineering. Functional modifications to scaffolds will further promote efficient strategies for production.
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Affiliation(s)
- Zhenya Chen
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, No. 5 South Zhongguancun Street, 100081, Beijing, China
| | - Tong Wu
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, No. 5 South Zhongguancun Street, 100081, Beijing, China
| | - Shengzhu Yu
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, No. 5 South Zhongguancun Street, 100081, Beijing, China
| | - Min Li
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, No. 5 South Zhongguancun Street, 100081, Beijing, China
| | - Xuanhe Fan
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, No. 5 South Zhongguancun Street, 100081, Beijing, China
| | - Yi-Xin Huo
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, No. 5 South Zhongguancun Street, 100081, Beijing, China.
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8
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Morlino MS, Serna García R, Savio F, Zampieri G, Morosinotto T, Treu L, Campanaro S. Cupriavidus necator as a platform for polyhydroxyalkanoate production: An overview of strains, metabolism, and modeling approaches. Biotechnol Adv 2023; 69:108264. [PMID: 37775073 DOI: 10.1016/j.biotechadv.2023.108264] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/18/2023] [Accepted: 09/26/2023] [Indexed: 10/01/2023]
Abstract
Cupriavidus necator is a bacterium with a high phenotypic diversity and versatile metabolic capabilities. It has been extensively studied as a model hydrogen oxidizer, as well as a producer of polyhydroxyalkanoates (PHA), plastic-like biopolymers with a high potential to substitute petroleum-based materials. Thanks to its adaptability to diverse metabolic lifestyles and to the ability to accumulate large amounts of PHA, C. necator is employed in many biotechnological processes, with particular focus on PHA production from waste carbon sources. The large availability of genomic information has enabled a characterization of C. necator's metabolism, leading to the establishment of metabolic models which are used to devise and optimize culture conditions and genetic engineering approaches. In this work, the characteristics of available C. necator strains and genomes are reviewed, underlining how a thorough comprehension of the genetic variability of C. necator is lacking and it could be instrumental for wider application of this microorganism. The metabolic paradigms of C. necator and how they are connected to PHA production and accumulation are described, also recapitulating the variety of carbon substrates used for PHA accumulation, highlighting the most promising strategies to increase the yield. Finally, the review describes and critically analyzes currently available genome-scale metabolic models and reduced metabolic network applications commonly employed in the optimization of PHA production. Overall, it appears that the capacity of C. necator of performing CO2 bioconversion to PHA is still underexplored, both in biotechnological applications and in metabolic modeling. However, the accurate characterization of this organism and the efforts in using it for gas fermentation can help tackle this challenging perspective in the future.
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Affiliation(s)
- Maria Silvia Morlino
- Department of Biology, University of Padua, via U. Bassi 58/b, 35131 Padova, Italy
| | - Rebecca Serna García
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Avinguda de la Universitat s/n, 46100 Burjassot, Valencia, Spain
| | - Filippo Savio
- Department of Biology, University of Padua, via U. Bassi 58/b, 35131 Padova, Italy
| | - Guido Zampieri
- Department of Biology, University of Padua, via U. Bassi 58/b, 35131 Padova, Italy
| | - Tomas Morosinotto
- Department of Biology, University of Padua, via U. Bassi 58/b, 35131 Padova, Italy
| | - Laura Treu
- Department of Biology, University of Padua, via U. Bassi 58/b, 35131 Padova, Italy.
| | - Stefano Campanaro
- Department of Biology, University of Padua, via U. Bassi 58/b, 35131 Padova, Italy
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9
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Yu Y, Pi S, Ke T, Zhou B, Chao W, Yang Y, Li Z, Li G, Ren N, Gao X, Lu L. Artificial Soil-Like Material Enhances CO 2 Bio-Valorization into Chemicals in Gas Fermentation. ACS APPLIED MATERIALS & INTERFACES 2023; 15:53488-53497. [PMID: 37929338 DOI: 10.1021/acsami.3c12627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2023]
Abstract
Gas fermentation offers a carbon-neutral route for producing industrial feedstocks using autotrophic microbes to convert carbon dioxide (CO2) in waste gases, such as industrial emissions and biogas, into valuable chemicals or biofuels. However, slow microbial metabolism owing to low gaseous solubility causes significant challenges in gas fermentation. Although chemical or genetic manipulations have been explored to improve gas fermentation, they are either nonsustainable or complex. Herein, an artificial soil-like material (SLM) inspired by natural soil was fabricated to improve the growth and metabolism ofCupriavidus necatorfor enhanced poly-β-hydroxybutyrate (PHB) biosynthesis from CO2 and hydrogen (H2). Porous SLM comprises low-cost nanoclay, boehmite, and starch and serves as a biocarrier to facilitate the colonization of bacteria and delivery of CO2 to bacteria. With 3.0 g/L SLM addition, the solubility of CO2 in water increased by ∼4 times and biomass and PHB production boosted by 29 and 102%, respectively, in the 24 h culture. In addition, a positive modulation was observed in the metabolism of PHB biosynthesis. PHB biosynthesis-associated gene expression was found to be enhanced in response to the SLM addition. The concentrations of intermediates in the metabolic pathway of PHB biosynthesis, such as pyruvate and acetyl-CoA, as well as reducing energy (ATP and NADPH) significantly increased with SLM addition. SLM also demonstrated the merits of easy fabrication, high stability, recyclability, and plasticity, thereby indicating its considerable potential for large-scale application in gas fermentation.
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Affiliation(s)
- Yongjie Yu
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Shanshan Pi
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Tan Ke
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Baiqin Zhou
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Weixiang Chao
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Yang Yang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Zhida Li
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Guifeng Li
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Xiang Gao
- Center for Materials Synthetic Biology, CAS Key Laboratory of Quantitative Engineering Biology of CAS, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academic of Science, Shenzhen 518000, China
| | - Lu Lu
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
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10
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Tang R, Yuan X, Yang J. Problems and corresponding strategies for converting CO 2 into value-added products in Cupriavidus necator H16 cell factories. Biotechnol Adv 2023; 67:108183. [PMID: 37286176 DOI: 10.1016/j.biotechadv.2023.108183] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/17/2023] [Accepted: 05/31/2023] [Indexed: 06/09/2023]
Abstract
Elevated CO2 emissions have substantially altered the worldwide climate, while the excessive reliance on fossil fuels has exacerbated the energy crisis. Therefore, the conversion of CO2 into fuel, petroleum-based derivatives, drug precursors, and other value-added products is expected. Cupriavidus necator H16 is the model organism of the "Knallgas" bacterium and is considered to be a microbial cell factory as it can convert CO2 into various value-added products. However, the development and application of C. necator H16 cell factories has several limitations, including low efficiency, high cost, and safety concerns arising from the autotrophic metabolic characteristics of the strains. In this review, we first considered the autotrophic metabolic characteristics of C. necator H16, and then categorized and summarized the resulting problems. We also provided a detailed discussion of some corresponding strategies concerning metabolic engineering, trophic models, and cultivation mode. Finally, we provided several suggestions for improving and combining them. This review might help in the research and application of the conversion of CO2 into value-added products in C. necator H16 cell factories.
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Affiliation(s)
- Ruohao Tang
- Energy-rich Compounds Production by Photosynthetic Carbon Fixation Research Center, Shandong Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, Shandong Province, People's Republic of China; Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, Shandong Province, People's Republic of China
| | - Xianzheng Yuan
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, Shandong Province, People's Republic of China
| | - Jianming Yang
- Energy-rich Compounds Production by Photosynthetic Carbon Fixation Research Center, Shandong Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, Shandong Province, People's Republic of China.
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Yu F, Zhao X, Zhou J, Lu W, Li J, Chen J, Du G. Biosynthesis of High-Active Hemoproteins by the Efficient Heme-Supply Pichia Pastoris Chassis. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2302826. [PMID: 37649147 PMCID: PMC10602571 DOI: 10.1002/advs.202302826] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 07/17/2023] [Indexed: 09/01/2023]
Abstract
Microbial synthesis of valuable hemoproteins has become a popular research topic, and Pichia pastoris is a versatile platform for the industrial production of recombinant proteins. However, the inadequate supply of heme limits the synthesis of high-active hemoproteins. Here a strategy for enhancing intracellular heme biosynthesis to improve the titers and functional activities of hemoproteins is reported. After selecting a suitable expressional strategy for globins, the efficient heme-supply P. pastoris chassis is established by removing the spatial segregation during heme biosynthesis, optimizing precursor synthesis, assembling rate-limiting enzymes using protein scaffolds, and inhibiting heme degradation. This robust chassis produces several highly active hemoproteins, including porcine myoglobin, soy hemoglobin, Vitreoscilla hemoglobin, and P450-BM3, which can be used in the development of artificial meat, high-cell-density fermentation, and whole-cell catalytic synthesis of high-value-added compounds. Furthermore, the engineered chassis strain has great potential for producing and applying other hemoproteins with high activities in various fields.
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Affiliation(s)
- Fei Yu
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Xinrui Zhao
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Jingwen Zhou
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Wei Lu
- Dongsheng Biotech Co., Ltd.91–92 Junmin RoadTaixingJiangsu225432China
| | - Jianghua Li
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Jian Chen
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
| | - Guocheng Du
- Key Laboratory of Industrial BiotechnologyMinistry of EducationSchool of BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Science Center for Future FoodsJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Jiangsu Province Engineering Research Center of Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Engineering Research Center of Ministry of Education on Food Synthetic BiotechnologyJiangnan University1800 Lihu RoadWuxiJiangsu214122China
- Key Laboratory of Carbohydrate Chemistry and BiotechnologyMinistry of EducationJiangnan University1800 Lihu RoadWuxiJiangsu214122China
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Collas F, Dronsella BB, Kubis A, Schann K, Binder S, Arto N, Claassens NJ, Kensy F, Orsi E. Engineering the biological conversion of formate into crotonate in Cupriavidus necator. Metab Eng 2023; 79:49-65. [PMID: 37414134 DOI: 10.1016/j.ymben.2023.06.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 06/08/2023] [Accepted: 06/29/2023] [Indexed: 07/08/2023]
Abstract
To advance the sustainability of the biobased economy, our society needs to develop novel bioprocesses based on truly renewable resources. The C1-molecule formate is increasingly proposed as carbon and energy source for microbial fermentations, as it can be efficiently generated electrochemically from CO2 and renewable energy. Yet, its biotechnological conversion into value-added compounds has been limited to a handful of examples. In this work, we engineered the natural formatotrophic bacterium C. necator as cell factory to enable biological conversion of formate into crotonate, a platform short-chain unsaturated carboxylic acid of biotechnological relevance. First, we developed a small-scale (150-mL working volume) cultivation setup for growing C. necator in minimal medium using formate as only carbon and energy source. By using a fed-batch strategy with automatic feeding of formic acid, we could increase final biomass concentrations 15-fold compared to batch cultivations in flasks. Then, we engineered a heterologous crotonate pathway in the bacterium via a modular approach, where each pathway section was assessed using multiple candidates. The best performing modules included a malonyl-CoA bypass for increasing the thermodynamic drive towards the intermediate acetoacetyl-CoA and subsequent conversion to crotonyl-CoA through partial reverse β-oxidation. This pathway architecture was then tested for formate-based biosynthesis in our fed-batch setup, resulting in a two-fold higher titer, three-fold higher productivity, and five-fold higher yield compared to the strain not harboring the bypass. Eventually, we reached a maximum product titer of 148.0 ± 6.8 mg/L. Altogether, this work consists in a proof-of-principle integrating bioprocess and metabolic engineering approaches for the biological upgrading of formate into a value-added platform chemical.
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Affiliation(s)
| | - Beau B Dronsella
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | | | - Karin Schann
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | | | | | - Nico J Claassens
- Laboratory of Microbiology, Wageningen University, Wageningen, the Netherlands
| | | | - Enrico Orsi
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm, Germany.
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Jiang N, Wang M, Song L, Yu D, Zhou S, Li Y, Li H, Han X. Polyhydroxybutyrate production by recombinant Escherichia coli based on genes related to synthesis pathway of PHB from Massilia sp. UMI-21. Microb Cell Fact 2023; 22:129. [PMID: 37452345 PMCID: PMC10347839 DOI: 10.1186/s12934-023-02142-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Accepted: 07/05/2023] [Indexed: 07/18/2023] Open
Abstract
BACKGROUND Polyhydroxybutyrate (PHB) is currently the most common polymer produced by natural bacteria and alternative to conventional petrochemical-based plastics due to its similar material properties and biodegradability. Massilia sp. UMI-21, a newly found bacterium, could produce PHB from starch, maltotriose, or maltose, etc. and could serve as a candidate for seaweed-degrading bioplastic producers. However, the genes involved in PHB metabolism in Massilia sp. UMI-21 are still unclear. RESULTS In the present study, we assembled and annotated the genome of Massilia sp. UMI-21, identified genes related to the metabolism of PHB, and successfully constructed recombinant Escherichia coli harboring PHB-related genes (phaA2, phaB1 and phaC1) of Massilia sp. UMI-21, which showed up to 139.41% more product. Also, the vgb gene (encoding Vitreoscilla hemoglobin) was introduced into the genetically engineered E. coli and gained up to 117.42% more cell dry weight, 213.30% more PHB-like production and 44.09% more product content. Fermentation products extracted from recombinant E. coli harboring pETDuet1-phaA2phaB1-phaC1 and pETDuet1-phaA2phaB1-phaC1-vgb were identified as PHB by Fourier Transform Infrared and Proton nuclear magnetic resonance spectroscopy analysis. Furthermore, the decomposition temperature at 10% weight loss of PHB extracted from Massilia sp. UMI-21, recombinant E. coli DH5α-pETDuet1-phaA2phaB1-phaC1 and DH5α-pETDuet1-phaA2phaB1-phaC1-vgb was 276.5, 278.7 and 286.3 °C, respectively, showing good thermal stability. CONCLUSIONS Herein, we presented the whole genome information of PHB-producing Massilia sp. UMI-21 and constructed novel recombinant strains using key genes in PHB synthesis of strain UMI-21 and the vgb gene. This genetically engineered E. coli strain can serve as an effective novel candidate in E. coli cell factory for PHB production by the rapid cell growth and high PHB production.
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Affiliation(s)
- Nan Jiang
- Engineering Research Center of Chinese Ministry of Education for Edible and Medicinal Fungi, Jilin Agricultural University, Changchun, China
- Jilin Province Key Laboratory of Fungal Phenomics, Jilin Agricultural University, Changchun, China
| | - Ming Wang
- School of Life Science and Technology, Changchun University of Science and Technology, Changchun, China
| | - Linxin Song
- Engineering Research Center of Chinese Ministry of Education for Edible and Medicinal Fungi, Jilin Agricultural University, Changchun, China
- Jilin Province Key Laboratory of Fungal Phenomics, Jilin Agricultural University, Changchun, China
| | - Dengbin Yu
- Engineering Research Center of Chinese Ministry of Education for Edible and Medicinal Fungi, Jilin Agricultural University, Changchun, China
- Jilin Province Key Laboratory of Fungal Phenomics, Jilin Agricultural University, Changchun, China
| | - Shuangzi Zhou
- School of Life Science and Technology, Changchun University of Science and Technology, Changchun, China
| | - Yu Li
- Engineering Research Center of Chinese Ministry of Education for Edible and Medicinal Fungi, Jilin Agricultural University, Changchun, China
- Jilin Province Key Laboratory of Fungal Phenomics, Jilin Agricultural University, Changchun, China
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Haiyan Li
- School of Life Science and Technology, Changchun University of Science and Technology, Changchun, China
| | - Xuerong Han
- Engineering Research Center of Chinese Ministry of Education for Edible and Medicinal Fungi, Jilin Agricultural University, Changchun, China.
- Jilin Province Key Laboratory of Fungal Phenomics, Jilin Agricultural University, Changchun, China.
- School of Life Science and Technology, Changchun University of Science and Technology, Changchun, China.
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14
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Jo YY, Park S, Gong G, Roh S, Yoo J, Ahn JH, Lee SM, Um Y, Kim KH, Ko JK. Enhanced production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with modulated 3-hydroxyvalerate fraction by overexpressing acetolactate synthase in Cupriavidus necator H16. Int J Biol Macromol 2023:125166. [PMID: 37270139 DOI: 10.1016/j.ijbiomac.2023.125166] [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: 03/28/2023] [Revised: 05/16/2023] [Accepted: 05/29/2023] [Indexed: 06/05/2023]
Abstract
The elastomeric properties of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), a biodegradable copolymer, strongly depend on the molar composition of 3-hydroxyvalerate (3 HV). This paper reports an improved artificial pathway for enhancing the 3HV component during PHBV biosynthesis from a structurally unrelated carbon source by Cupriavidus necator H16. To increase the intracellular accumulation of propionyl-CoA, a key precursor of the 3HV monomer, we developed a recombinant strain by genetically manipulating the branched-chain amino acid (e.g., valine, isoleucine) pathways. Overexpression of the heterologous feedback-resistant acetolactate synthase (alsS), (R)-citramalate synthase (leuA), homologous 3-ketothiolase (bktB), and the deletion of 2-methylcitrate synthase (prpC) resulted in biosynthesis of 42.5 % (g PHBV/g dry cell weight) PHBV with 64.9 mol% 3 HV monomer from fructose as the sole carbon source. This recombinant strain also accumulated the highest PHBV content of 54.5 % dry cell weight (DCW) with 24 mol% 3HV monomer from CO2 ever reported. The lithoautotrophic cell growth and PHBV production by the recombinant C. necator were promoted by oxygen stress. The thermal properties of PHBV showed a decreasing trend of the glass transition and melting temperatures with increasing 3 HV fraction. The average molecular weights of PHBV with modulated 3 HV fractions were between 20 and 26 × 104 g/mol.
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Affiliation(s)
- Young Yun Jo
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Soyoung Park
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Gyeongtaek Gong
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul 02792, Republic of Korea
| | - Soonjong Roh
- Biomaterials Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Jin Yoo
- Biomaterials Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Jung Ho Ahn
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul 02792, Republic of Korea
| | - Sun-Mi Lee
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul 02792, Republic of Korea
| | - Youngsoon Um
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul 02792, Republic of Korea
| | - Kyoung Heon Kim
- Department of Biotechnology, Korea University, Seoul 02841, Republic of Korea
| | - Ja Kyong Ko
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul 02792, Republic of Korea.
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15
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Weng C, Tang R, Peng X, Han Y. Co-conversion of lignocellulose-derived glucose, xylose, and aromatics to polyhydroxybutyrate by metabolically engineered Cupriavidus necator. BIORESOURCE TECHNOLOGY 2023; 374:128762. [PMID: 36813047 DOI: 10.1016/j.biortech.2023.128762] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/15/2023] [Accepted: 02/17/2023] [Indexed: 06/18/2023]
Abstract
Utilization of all major components of lignocellulose is essential for biomass biorefining. Glucose, xylose, and lignin-derived aromatics can be generated from cellulose, hemicellulose, and lignin of lignocellulose degradation through pretreatment and hydrolysis. In present work, Cupriavidus necator H16 was engineered to utilize glucose, xylose, p-coumaric acid, and ferulic acid simultaneously by multi-step genetic engineering. Firstly, genetic modification and adaptive laboratory evolution were performed to promote glucose transmembrane transport and metabolism. Xylose metabolism was then engineered by integrating genes xylAB (xylose isomerase and xylulokinase) and xylE (proton-coupled symporter) in the locus of ldh (lactate dehydrogenase) and ackA (acetate kinase) on the genome, respectively. Thirdly, p-coumaric acid and ferulic acid metabolism was achieved by constructing an exogenous CoA-dependent non-β-oxidation pathway. Using corn stover hydrolysates as carbon sources, the resulting engineered strain Reh06 simultaneously converted all components of glucose, xylose, p-coumaric acid, and ferulic acid to produce 11.51 g/L polyhydroxybutyrate.
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Affiliation(s)
- Caihong Weng
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ruohao Tang
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaowei Peng
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yejun Han
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.
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16
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Kim S, Jang YJ, Gong G, Lee SM, Um Y, Kim KH, Ko JK. Engineering Cupriavidus necator H16 for enhanced lithoautotrophic poly(3-hydroxybutyrate) production from CO 2. Microb Cell Fact 2022; 21:231. [PMCID: PMC9636797 DOI: 10.1186/s12934-022-01962-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 10/13/2022] [Indexed: 11/06/2022] Open
Abstract
Background A representative hydrogen-oxidizing bacterium Cupriavidus necator H16 has attracted much attention as hosts to recycle carbon dioxide (CO2) into a biodegradable polymer, poly(R)-3-hydroxybutyrate (PHB). Although C. necator H16 has been used as a model PHB producer, the PHB production rate from CO2 is still too low for commercialization. Results Here, we engineer the carbon fixation metabolism to improve CO2 utilization and increase PHB production. We explore the possibilities to enhance the lithoautotrophic cell growth and PHB production by introducing additional copies of transcriptional regulators involved in Calvin Benson Bassham (CBB) cycle. Both cbbR and regA-overexpressing strains showed the positive phenotypes for 11% increased biomass accumulation and 28% increased PHB production. The transcriptional changes of key genes involved in CO2—fixing metabolism and PHB production were investigated. Conclusions The global transcriptional regulator RegA plays an important role in the regulation of carbon fixation and shows the possibility to improve autotrophic cell growth and PHB accumulation by increasing its expression level. This work represents another step forward in better understanding and improving the lithoautotrophic PHB production by C. necator H16. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01962-7.
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Affiliation(s)
- Soyoung Kim
- grid.35541.360000000121053345Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792 Republic of Korea
| | - Yong Jae Jang
- grid.35541.360000000121053345Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792 Republic of Korea
| | - Gyeongtaek Gong
- grid.35541.360000000121053345Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792 Republic of Korea ,grid.412786.e0000 0004 1791 8264Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul, 02792 Republic of Korea
| | - Sun-Mi Lee
- grid.35541.360000000121053345Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792 Republic of Korea ,grid.412786.e0000 0004 1791 8264Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul, 02792 Republic of Korea
| | - Youngsoon Um
- grid.35541.360000000121053345Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792 Republic of Korea ,grid.412786.e0000 0004 1791 8264Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul, 02792 Republic of Korea
| | - Kyoung Heon Kim
- grid.222754.40000 0001 0840 2678Department of Biotechnology, Graduate School, Korea University, Seoul, 02841 Republic of Korea
| | - Ja Kyong Ko
- grid.35541.360000000121053345Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul, 02792 Republic of Korea ,grid.412786.e0000 0004 1791 8264Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul, 02792 Republic of Korea
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17
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Han X, Liu J, Tian S, Tao F, Xu P. Microbial cell factories for bio-based biodegradable plastics production. iScience 2022; 25:105462. [DOI: 10.1016/j.isci.2022.105462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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18
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Zhang L, Jiang Z, Tsui TH, Loh KC, Dai Y, Tong YW. A Review on Enhancing Cupriavidus necator Fermentation for Poly(3-hydroxybutyrate) (PHB) Production From Low-Cost Carbon Sources. Front Bioeng Biotechnol 2022; 10:946085. [PMID: 35928944 PMCID: PMC9343952 DOI: 10.3389/fbioe.2022.946085] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 06/20/2022] [Indexed: 11/13/2022] Open
Abstract
In the context of a circular economy, bioplastic production using biodegradable materials such as poly(3-hydroxybutyrate) (PHB) has been proposed as a promising solution to fundamentally solve the disposal issue of plastic waste. PHB production techniques through fermentation of PHB-accumulating microbes such as Cupriavidus necator have been revolutionized over the past several years with the development of new strategies such as metabolic engineering. This review comprehensively summarizes the latest PHB production technologies via Cupriavidus necator fermentation. The mechanism of the biosynthesis pathway for PHB production was first assessed. PHB production efficiencies of common carbon sources, including food waste, lignocellulosic materials, glycerol, and carbon dioxide, were then summarized and critically analyzed. The key findings in enhancing strategies for PHB production in recent years, including pre-treatment methods, nutrient limitations, feeding optimization strategies, and metabolism engineering strategies, were summarized. Furthermore, technical challenges and future prospects of strategies for enhanced production efficiencies of PHB were also highlighted. Based on the overview of the current enhancing technologies, more pilot-scale and larger-scale tests are essential for future implementation of enhancing strategies in full-scale biogas plants. Critical analyses of various enhancing strategies would facilitate the establishment of more sustainable microbial fermentation systems for better waste management and greater efficiency of PHB production.
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Affiliation(s)
- Le Zhang
- NUS Environmental Research Institute, National University of Singapore, Singapore, Singapore
- Energy and Environmental Sustainability for Megacities (E2S2) Phase II, Campus for Research Excellence and Technological Enterprise (CREATE), Singapore, Singapore
| | - Zicheng Jiang
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, Singapore
| | - To-Hung Tsui
- NUS Environmental Research Institute, National University of Singapore, Singapore, Singapore
- Energy and Environmental Sustainability for Megacities (E2S2) Phase II, Campus for Research Excellence and Technological Enterprise (CREATE), Singapore, Singapore
| | - Kai-Chee Loh
- Energy and Environmental Sustainability for Megacities (E2S2) Phase II, Campus for Research Excellence and Technological Enterprise (CREATE), Singapore, Singapore
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, Singapore
| | - Yanjun Dai
- Energy and Environmental Sustainability for Megacities (E2S2) Phase II, Campus for Research Excellence and Technological Enterprise (CREATE), Singapore, Singapore
- School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Yen Wah Tong
- NUS Environmental Research Institute, National University of Singapore, Singapore, Singapore
- Energy and Environmental Sustainability for Megacities (E2S2) Phase II, Campus for Research Excellence and Technological Enterprise (CREATE), Singapore, Singapore
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore, Singapore
- *Correspondence: Yen Wah Tong,
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19
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Borrero‐de Acuña JM, Poblete‐Castro I. Rational engineering of natural polyhydroxyalkanoates producing microorganisms for improved synthesis and recovery. Microb Biotechnol 2022; 16:262-285. [PMID: 35792877 PMCID: PMC9871526 DOI: 10.1111/1751-7915.14109] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 06/14/2022] [Indexed: 01/27/2023] Open
Abstract
Microbial production of biopolymers derived from renewable substrates and waste streams reduces our heavy reliance on petrochemical plastics. One of the most important biodegradable polymers is the family of polyhydroxyalkanoates (PHAs), naturally occurring intracellular polyoxoesters produced for decades by bacterial fermentation of sugars and fatty acids at the industrial scale. Despite the advances, PHA production still suffers from heavy costs associated with carbon substrates and downstream processing to recover the intracellular product, thus restricting market positioning. In recent years, model-aided metabolic engineering and novel synthetic biology approaches have spurred our understanding of carbon flux partitioning through competing pathways and cellular resource allocation during PHA synthesis, enabling the rational design of superior biopolymer producers and programmable cellular lytic systems. This review describes these attempts to rationally engineering the cellular operation of several microbes to elevate PHA production on specific substrates and waste products. We also delve into genome reduction, morphology, and redox cofactor engineering to boost PHA biosynthesis. Besides, we critically evaluate engineered bacterial strains in various fermentation modes in terms of PHA productivity and the period required for product recovery.
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Affiliation(s)
| | - Ignacio Poblete‐Castro
- Biosystems Engineering LaboratoryDepartment of Chemical and Bioprocess EngineeringUniversidad de Santiago de Chile (USACH)SantiagoChile
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20
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Zhao L, Cai S, Zhang J, Zhang Q, Chen L, Ji X, Zhang R, Cai T. Poly(3-hydroxybutyrate) biosynthesis under non-sterile conditions: Piperazine as nitrogen substrate control switch. Int J Biol Macromol 2022; 209:1457-1464. [PMID: 35461873 DOI: 10.1016/j.ijbiomac.2022.04.122] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 04/14/2022] [Accepted: 04/17/2022] [Indexed: 11/16/2022]
Abstract
Poly(3-hydroxybutyrate) (PHB), as a kind of bioplastics for sustainable development, can be synthesized by various microorganisms, however, the high cost of its microbial fermentation is a challenge for its large-scale application. In this study, piperazine degrading strain, Paracoccus sp. TOH, was developed as an excellent chassis for open PHB fermentation with piperazine as controlling element. Whole-genome analysis showed that TOH possesses multi-substrate metabolic pathways to synthesize PHB. Next, TOH could achieve a maximum PHB concentration of 2.42 g L-1, representing a yield of 0.36 g-PHB g-1-glycerol when C/N ratio was set as 60:1 with 10 g L-1 glycerol as substrate. Furthermore, TOH could even synthesize 0.39 g-PHB g-1-glycerol under non-sterile conditions when piperazine was fed with a suitable rate of 1 mg L-1 h-1. 16S rRNA gene sequencing analysis showed that microbial contamination could be effectively inhibited through the regulation of piperazine under non-sterile conditions and TOH dominated the microbial community with a relative abundance of 72.3% at the end of the operational period. This study offers an inspired open PHB fermentation system with piperazine as the control switch, which will realize the goal of efficient industrial biotechnology as well as industrial wastewater treatment.
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Affiliation(s)
- Leizhen Zhao
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Shu Cai
- Department of Biological and Agricultural Engineering, University of California, Davis, CA 95616, United States
| | - Jiaqi Zhang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Qi Zhang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Liwei Chen
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Xiaoming Ji
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Ruihong Zhang
- Department of Biological and Agricultural Engineering, University of California, Davis, CA 95616, United States
| | - Tianming Cai
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China.
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A genome-scale metabolic model of Cupriavidus necator H16 integrated with TraDIS and transcriptomic data reveals metabolic insights for biotechnological applications. PLoS Comput Biol 2022; 18:e1010106. [PMID: 35604933 PMCID: PMC9166356 DOI: 10.1371/journal.pcbi.1010106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 06/03/2022] [Accepted: 04/14/2022] [Indexed: 11/29/2022] Open
Abstract
Exploiting biological processes to recycle renewable carbon into high value platform chemicals provides a sustainable and greener alternative to current reliance on petrochemicals. In this regard Cupriavidus necator H16 represents a particularly promising microbial chassis due to its ability to grow on a wide range of low-cost feedstocks, including the waste gas carbon dioxide, whilst also naturally producing large quantities of polyhydroxybutyrate (PHB) during nutrient-limited conditions. Understanding the complex metabolic behaviour of this bacterium is a prerequisite for the design of successful engineering strategies for optimising product yields. We present a genome-scale metabolic model (GSM) of C. necator H16 (denoted iCN1361), which is directly constructed from the BioCyc database to improve the readability and reusability of the model. After the initial automated construction, we have performed extensive curation and both theoretical and experimental validation. By carrying out a genome-wide essentiality screening using a Transposon-directed Insertion site Sequencing (TraDIS) approach, we showed that the model could predict gene knockout phenotypes with a high level of accuracy. Importantly, we indicate how experimental and computational predictions can be used to improve model structure and, thus, model accuracy as well as to evaluate potential false positives identified in the experiments. Finally, by integrating transcriptomics data with iCN1361 we create a condition-specific model, which, importantly, better reflects PHB production in C. necator H16. Observed changes in the omics data and in-silico-estimated alterations in fluxes were then used to predict the regulatory control of key cellular processes. The results presented demonstrate that iCN1361 is a valuable tool for unravelling the system-level metabolic behaviour of C. necator H16 and can provide useful insights for designing metabolic engineering strategies. Genome-scale metabolic models (GSMs) provide a tool for unravelling the complex metabolic behaviour of bacteria and how they adapt to changing environments and genetic perturbations, and thus offer invaluable insights for biotechnology applications. For a GSM to be used efficiently for strain development purposes, however, the model must be easily readable and reusable by other researchers, whilst being able to predict metabolic behaviour with a high level of accuracy. In this work, we developed a GSM for Cupriavidus necator H16 that is linked to the BioCyc database, which provides an efficient way of application, model update, integration of experimental data and network visualisation for other researchers. Using our model, we demonstrate how integrating experimental observations, including Transposon-directed Insertion site Sequencing (TraDIS) and omics data, can be used to compensate for the lack of regulatory, kinetic and thermodynamic information in GSMs, and thus improve model accuracy. Importantly, we found that TraDIS in vivo screening and GSM analysis are complementary approaches, which can be used in combination to provide reliable gene essentiality predictions. Overall, our results offer an informed strategy for the deliberate manipulation of C. necator H16 metabolic capabilities, towards its industrial application to convert greenhouse gases into biochemicals and biofuels.
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Abstract
Carbon dioxide is a major greenhouse gas, and its fixation and transformation are receiving increasing attention. Biofixation of CO2 is an eco–friendly and efficient way to reduce CO2, and six natural CO2 fixation pathways have been identified in microorganisms and plants. In this review, the six pathways along with the most recent identified variant pathway were firstly comparatively characterized. The key metabolic process and enzymes of the CO2 fixation pathways were also summarized. Next, the enzymes of Rubiscos, biotin-dependent carboxylases, CO dehydrogenase/acetyl-CoA synthase, and 2-oxoacid:ferredoxin oxidoreductases, for transforming inorganic carbon (CO2, CO, and bicarbonate) to organic chemicals, were specially analyzed. Then, the factors including enzyme properties, CO2 concentrating, energy, and reducing power requirements that affect the efficiency of CO2 fixation were discussed. Recent progress in improving CO2 fixation through enzyme and metabolic engineering was then summarized. The artificial CO2 fixation pathways with thermodynamical and/or energetical advantages or benefits and their applications in biosynthesis were included as well. The challenges and prospects of CO2 biofixation and conversion are discussed.
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Xu Y, Li Y, Wu Z, Lu Y, Tao G, Zhang L, Ding Z, Shi G. Combining Precursor-Directed Engineering with Modular Designing: An Effective Strategy for De Novo Biosynthesis of l-DOPA in Bacillus licheniformis. ACS Synth Biol 2022; 11:700-712. [PMID: 35076224 DOI: 10.1021/acssynbio.1c00411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
3-Hydroxy-l-tyrosine (l-DOPA) is a promising drug for treating Parkinson's disease. Tyrosine hydroxylase catalyzes the microbial synthesis of l-DOPA, which is hindered by the efficiency of catalysis, the supply of cofactor tetrahydrobiopterin, and the regulation of the pathway. In this study, the modular engineering strategy in Bacillus licheniformis was identified to effectively enhance l-DOPA production. First, the catalytic efficiency of biocatalyst tyrosine hydroxylase from Streptosporangium roseum DSM 43021 (SrTH) was improved by 20.3% by strengthening its affinity toward tetrahydrobiopterin. Second, the tetrahydrobiopterin supply pool was increased by bottleneck gene expression, oxygen transport facilitation, budC (encoding meso-2,3-butanediol dehydrogenase) deletion, and tetrahydrobiopterin regeneration using a native YfkO nitroreductase. The strain 45ABvC successfully produced tetrahydrobiopterin, which was detected as pterin (112.48 mg/L), the oxidation product of tetrahydrobiopterin. Finally, the yield of precursor l-tyrosine reached 148 mg/gDCW, with an increase of 71%, with the deletion of a novel spliced transcript 41sRNA associated with the regulation of the shikimate pathway. The engineered strain 45ABvCS::PD produced 167.14 mg/L (2.41 times of wild-type strain) and 1290 mg/L l-DOPA in a shake flask and a 15 L bioreactor, respectively, using a fermentation strategy on a mixture of carbon sources. This study holds great potential for constructing a microbial source of l-DOPA and its high-value downstream pharmaceuticals.
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Affiliation(s)
- Yinbiao Xu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People’s Republic of China
- National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
- Engineering Research Center for Applied Microbiology of Henan Province, School of Life Sciences, Henan University, Kaifeng 475004, People’s Republic of China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
| | - Youran Li
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People’s Republic of China
- National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
| | - Zhiyong Wu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People’s Republic of China
- National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
| | - Yiming Lu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People’s Republic of China
- National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
| | - Guanjun Tao
- State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
| | - Liang Zhang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People’s Republic of China
- National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
| | - Zhongyang Ding
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People’s Republic of China
- National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
| | - Guiyang Shi
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, People’s Republic of China
- National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, People’s Republic of China
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24
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Boy C, Lesage J, Alfenore S, Guillouet SE, Gorret N. Study of plasmid-based expression level heterogeneity under plasmid-curing like conditions in Cupriavidus necator. J Biotechnol 2022; 345:17-29. [PMID: 34995560 DOI: 10.1016/j.jbiotec.2021.12.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 12/24/2021] [Accepted: 12/30/2021] [Indexed: 01/18/2023]
Abstract
Plasmid expression level heterogeneity in Cupriavidus necator was studied in response to stringent culture conditions, supposed to enhance plasmid instability, through plasmid curing strategies. Two plasmid curing strategies were compared based on their efficiency at generating heterogeneity in batch: rifampicin addition and temperature increase. A temperature increase from 30° to 37 °C was the most efficient plasmid curing strategy. To generate a heterogeneous population in terms of plasmid expression levels, successive batches at supra-optimal culture temperature (i.e. 37 °C) were initially conducted. Three distinct fluorescent subpopulations P0 (not fluorescent), P1 (low fluorescence intensity, median = 1 103) and P2 (high fluorescence intensity, median = 6 103) were obtained. From there, the chemostat culture was implemented to study the long-term stress response under well-controlled environment at defined dilution rates. For dilution rates comprised between 0.05 and 0.10 h-1, the subpopulation P2 (62% vs 90%) was favored compared to P1 cells (54% vs 1%), especially when growth rate increased. Our biosensor was efficient at discriminating subpopulation presenting different expression levels under stringent culture conditions. Plus, we showed that controlling growth kinetics had a stabilizing impact on plasmid expression levels, even under heterogeneous expression conditions.
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Affiliation(s)
- Catherine Boy
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Julie Lesage
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | | | | | - Nathalie Gorret
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France.
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25
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Pavan M, Reinmets K, Garg S, Mueller AP, Marcellin E, Köpke M, Valgepea K. Advances in systems metabolic engineering of autotrophic carbon oxide-fixing biocatalysts towards a circular economy. Metab Eng 2022; 71:117-141. [DOI: 10.1016/j.ymben.2022.01.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 12/16/2022]
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26
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Zhou K. Engineering microbes to synthesize functionalized biopolymers. J Mater Chem B 2022; 10:7132-7135. [DOI: 10.1039/d2tb01063a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Engineering metabolism of microbes has allowed simultaneous co-production of functional small molecules and biopolymers. This Perspective briefly introduced its working principles and summarized my views on how this approach could...
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27
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Jo SY, Son J, Sohn YJ, Lim SH, Lee JY, Yoo JI, Park SY, Na JG, Park SJ. A shortcut to carbon-neutral bioplastic production: Recent advances in microbial production of polyhydroxyalkanoates from C1 resources. Int J Biol Macromol 2021; 192:978-998. [PMID: 34656544 DOI: 10.1016/j.ijbiomac.2021.10.066] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 10/04/2021] [Accepted: 10/09/2021] [Indexed: 12/18/2022]
Abstract
Since the 20th century, plastics that are widely being used in general life and industries are causing enormous plastic waste problems since improperly discarded plastics barely degrade and decompose. Thus, the demand for polyhydroxyalkanoates (PHAs), biodegradable polymers with material properties similar to conventional petroleum-based plastics, has been increased so far. The microbial production of PHAs is an environment-friendly solution for the current plastic crisis, however, the carbon sources for the microbial PHA production is a crucial factor to be considered in terms of carbon-neutrality. One‑carbon (C1) resources, such as methane, carbon monoxide, and carbon dioxide, are greenhouse gases and are abundantly found in nature and industry. C1 resources as the carbon sources for PHA production have a completely closed carbon loop with much advances; i) fast carbon circulation with direct bioconversion process and ii) simple fermentation procedure without sterilization as non-preferable nutrients. This review discusses the biosynthesis of PHAs based on C1 resource utilization by wild-type and metabolically engineered microbial host strains via biorefinery processes.
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Affiliation(s)
- Seo Young Jo
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Jina Son
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Yu Jung Sohn
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Seo Hyun Lim
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Ji Yeon Lee
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Jee In Yoo
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Se Young Park
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Jeong-Geol Na
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul, Republic of Korea.
| | - Si Jae Park
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea.
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28
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Zhang Y, Zhou X, Yao Y, Xu Q, Shi H, Wang K, Feng W, Shen Y. Coexpression of VHb and MceG genes in Mycobacterium sp. Strain LZ2 enhances androstenone production via immobilized repeated batch fermentation. BIORESOURCE TECHNOLOGY 2021; 342:125965. [PMID: 34563820 DOI: 10.1016/j.biortech.2021.125965] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/12/2021] [Accepted: 09/14/2021] [Indexed: 06/13/2023]
Abstract
Androstenone production is limited by low-efficiency substrate transport and dissolved oxygen levels during fermentation. In this study, the coexpression of the optimized Vitreoscilla hemoglobin (VHb) and sterol transporter ATPase (MceG) genes in Mycobacterium sp. LZ2 (Msp) was investigated to alleviate dissolved oxygen and mass transfer limitations. Results revealed that Msp-vgb/mceG effectively improved the growth, production, and adaptation to dissolved oxygen compared with those of Msp. The increased catalase activity and reduced intracellular ROS levels enhanced cell viability and promoted transcription of genes critical for phytosterol metabolism. Bagasse as an immobilization carrier increased the productivity of Msp-vgb/mceG by 56%. Immobilized repeat batch fermentation reduced the biotransformation period from 60 days to 37 days and improved the productivity from 0.039 g/L/h to 0.069 g/L/h. To the best of our knowledge, this work is the first study on the immobilization of recombinant mycobacteria on bagasse for androstenone production.
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Affiliation(s)
- Yang Zhang
- School of Life Science, Liaocheng University, Liaocheng, Shandong 252059, PR China.
| | - Xiuling Zhou
- School of Life Science, Liaocheng University, Liaocheng, Shandong 252059, PR China
| | - Yingying Yao
- School of Life Science, Liaocheng University, Liaocheng, Shandong 252059, PR China
| | - Qianqian Xu
- School of Life Science, Liaocheng University, Liaocheng, Shandong 252059, PR China
| | - Haiying Shi
- School of Life Science, Liaocheng University, Liaocheng, Shandong 252059, PR China
| | - Kuiming Wang
- School of Life Science, Liaocheng University, Liaocheng, Shandong 252059, PR China
| | - Wei Feng
- School of Life Science, Liaocheng University, Liaocheng, Shandong 252059, PR China
| | - Yanbing Shen
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, PR China
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29
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Boy C, Lesage J, Alfenore S, Guillouet SE, Gorret N. Investigation of the robustness of Cupriavidus necator engineered strains during fed-batch cultures. AMB Express 2021; 11:151. [PMID: 34783891 PMCID: PMC8595445 DOI: 10.1186/s13568-021-01307-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 10/21/2021] [Indexed: 11/10/2022] Open
Abstract
It is of major interest to ensure stable and performant microbial bioprocesses, therefore maintaining high strain robustness is one of the major future challenges in industrial microbiology. Strain robustness can be defined as the persistence of genotypic and/or phenotypic traits in a system. In this work, robustness of an engineered strain is defined as plasmid expression stability, cultivability, membrane integrity and macroscopic cell behavior and was assessed in response to implementations of sugar feeding strategies (pulses and continuous) and two plasmid stabilization systems (kanamycin resistance and Post-Segregational Killing hok/sok). Fed-batch bioreactor cultures, relevant mode to reach high cell densities and higher cell generation number, were implemented to investigate the robustness of C. necator engineered strains. Host cells bore a recombinant plasmid encoding for a plasmid expression level monitoring system, based on eGFP fluorescence quantified by flow cytometry. We first showed that well-controlled continuous feeding in comparison to a pulse-based feeding allowed a better carbon use for protein synthesis (avoiding organic acid excretion), a lower heterogeneity of the plasmid expression and a lower cell permeabilization. Moreover, the plasmid stabilization system Post-Segregational Killing hok/sok, an autonomous system independent on external addition of compounds, showed the best ability to maintain plasmid expression level stability insuring a greater population homogeneity in the culture. Therefore, in the case of engineered C. necator, the PSK system hok/sok appears to be a relevant and an efficient alternative to antibiotic resistance system for selection pressure, especially, in the case of bioprocess development for economic and environmental reasons.
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Li JF, Li HF, Yao SM, Zhao MJ, Dong WX, Liang SK, Xu XY. Vitreoscilla Hemoglobin Improves Sophorolipid Production in Starmerella Bombicola O-13-1 Under Oxygen Limited Conditions. Front Bioeng Biotechnol 2021; 9:773104. [PMID: 34765597 PMCID: PMC8576176 DOI: 10.3389/fbioe.2021.773104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 10/12/2021] [Indexed: 11/13/2022] Open
Abstract
Sophorolipids (SLs) are homologous microbial secondary metabolites produced by Starmerella bombicola and have been widely applied in many industrial fields. The biosynthesis of SLs is a highly aerobic process and is often limited by low dissolved oxygen (DO) levels. In this study, the Vitreoscilla hemoglobin (VHb) gene was transformed into S. bombicola O-13-1 by homologous recombination to alleviate oxygen limitation. VHb expression improved the intracellular oxygen utilization efficiency under either oxygen-rich or oxygen-limited conditions. In shake flask culture, the production of SLs was higher in the recombinant (VHb+) strain than in the wild-type (VHb-) strain, while the oxygen uptake rate of the recombinant (VHb+) strain was significantly lower than that of the wild-type (VHb-) strain. In a 5 L bioreactor, the production of SLs did not increase significantly, but the DO level in the fermentation broth of the VHb+ strain was 21.8% higher than that of VHb- strain under oxygen-rich conditions. Compared to wide-type strains (VHb-), VHb expression enhanced SLs production by 25.1% in the recombinants (VHb+) under oxygen-limited conditions. In addition, VHb expression raised the transcription levels of key genes involved in the electron transfer chain (NDH, SDH, COX), TCA cycle (CS, ICD, KDG1) and SL synthesis (CYP52M1 and UGTA1) in the recombinant (VHb+) strains. VHb expression in S. bombicola could enhance SLs biosynthesis and intracellular oxygen utilization efficiency by increasing ATP production and cellular respiration. Our findings highlight the potential use of VHb to improve the oxygen utilization efficiency of S. bombicola in the industrial-scale production of SLs using industrial and agricultural by-products like molasses and waste oil as fermentation feedstock.
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Affiliation(s)
- Jun-Feng Li
- Shandong Provincial Key Laboratory of Biochemical Engineering, Qingdao Nucleic Acid Rapid Detection Engineering Research Center, College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao, China
| | - Hong-Fang Li
- Shandong Provincial Key Laboratory of Biochemical Engineering, Qingdao Nucleic Acid Rapid Detection Engineering Research Center, College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao, China
| | - Shu-Min Yao
- College of Life Science, Qufu Normal University, Qufu, China
| | - Meng-Juan Zhao
- Shandong Provincial Key Laboratory of Biochemical Engineering, Qingdao Nucleic Acid Rapid Detection Engineering Research Center, College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao, China
| | - Wen-Xun Dong
- Shandong Provincial Key Laboratory of Biochemical Engineering, Qingdao Nucleic Acid Rapid Detection Engineering Research Center, College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao, China
| | - Sheng-Kang Liang
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, China
| | - Xing-Yong Xu
- Fourth Institute of Oceanography, Ministry of Natural Resources, Beihai, China
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31
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Pan H, Wang J, Wu H, Li Z, Lian J. Synthetic biology toolkit for engineering Cupriviadus necator H16 as a platform for CO 2 valorization. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:212. [PMID: 34736496 PMCID: PMC8570001 DOI: 10.1186/s13068-021-02063-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 10/25/2021] [Indexed: 06/09/2023]
Abstract
BACKGROUND CO2 valorization is one of the effective methods to solve current environmental and energy problems, in which microbial electrosynthesis (MES) system has proved feasible and efficient. Cupriviadus necator (Ralstonia eutropha) H16, a model chemolithoautotroph, is a microbe of choice for CO2 conversion, especially with the ability to be employed in MES due to the presence of genes encoding [NiFe]-hydrogenases and all the Calvin-Benson-Basham cycle enzymes. The CO2 valorization strategy will make sense because the required hydrogen can be produced from renewable electricity independently of fossil fuels. MAIN BODY In this review, synthetic biology toolkit for C. necator H16, including genetic engineering vectors, heterologous gene expression elements, platform strain and genome engineering, and transformation strategies, is firstly summarized. Then, the review discusses how to apply these tools to make C. necator H16 an efficient cell factory for converting CO2 to value-added products, with the examples of alcohols, fatty acids, and terpenoids. The review is concluded with the limitation of current genetic tools and perspectives on the development of more efficient and convenient methods as well as the extensive applications of C. necator H16. CONCLUSIONS Great progress has been made on genetic engineering toolkit and synthetic biology applications of C. necator H16. Nevertheless, more efforts are expected in the near future to engineer C. necator H16 as efficient cell factories for the conversion of CO2 to value-added products.
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Affiliation(s)
- Haojie Pan
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Jia Wang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Haoliang Wu
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Zhongjian Li
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Jiazhang Lian
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
- Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou, 310027, China.
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The over-expression of phasin and regulator genes promoting the synthesis of polyhydroxybutyrate in Cupriavidus necator H16 under non-stress conditions. Appl Environ Microbiol 2021; 88:e0145821. [PMID: 34731058 DOI: 10.1128/aem.01458-21] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cupriavidus necator H16 is an ideal strain for polyhydroxybutyrate (PHB) production from CO2. Low-oxygen-stress can induce PHB synthesis in C. necator H16 while reducing bacterial growth under chemoautotrophic culture. The optimum growth and PHB synthesis of C. necator H16 cannot be achieved simultaneously, which restricts PHB production. The present study was initiated to address the issue through comparative transcriptome and gene function analysis. Firstly, the comparative transcriptome of C. necator H16 chemoautotrophically cultured under low-oxygen-stress and non-stress conditions was studied. Three types of transcription different genes were discovered: PHB enzymatic synthesis, PHB granulation, and regulators. Under low-oxygen-stress condition, acetoacetyl-CoA reductase gene phaB2, PHB synthase gene phaC2, phasins genes phaP1 and phaP2, regulators genes uspA and rpoN were up-regulated 3.0, 2.5, 1.8, 2.7, 3.5, 1.6 folds, respectively. Secondly, the functions of up-regulated genes and their applications in PHB synthesis were further studied. It was found that the over-expression of phaP1, phaP2, uspA, and rpoN can induce PHB synthesis under non-stress condition, while phaB2 and phaC2 have no significant effect. Under the optimum condition, PHB percentage content in C. necator H16 was respectively increased by 37.2%, 28.4%, 15.8%, and 41.0% with the over-expression of phaP1, phaP2, uspA, and rpoN, and the corresponding PHB production increased by 49.8%, 42.9%, 47.0%, and 77.5% under non-stress chemoautotrophic conditions. Similar promotion by phaP1, phaP2, uspA, and rpoN was observed in heterotrophically cultured C. necator H16. The PHB percentage content and PHB production were respectively increased by 54.4% and 103.1% with the over-expression of rpoN under non-stress heterotrophic conditions. Importance Microbial fixation of CO2 is an effective way to reduce greenhouse gases. Some microbes such as C. necator H16 usually accumulate PHB when they grow under stress. Low-oxygen-stress can induce PHB synthesis when C. necator H16 is autotrophically cultured with CO2, H2, and O2, while under stress, growth is restricted and total PHB yield is reduced. Achieving the optimal bacterial growth and PHB synthesis at the same time is an ideal condition for transforming CO2 into PHB by C. necator H16. The present study was initiated to clarify the molecular basis of low-oxygen-stress promoting PHB accumulation and to realize the optimal PHB production by C. necator H16. Genes up-regulated under non-stress conditions were identified through comparative transcriptome analysis and over-expression of phasin and regulator genes were demonstrated to promote PHB synthesis in C. necator H16.
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Ma Z, Liu D, Liu M, Cao Y, Song H. From CO<sub>2</sub> to high value-added products: Advances on carbon sequestration by <italic>Ralstonia eutropha</italic> H16. CHINESE SCIENCE BULLETIN-CHINESE 2021. [DOI: 10.1360/tb-2021-0584] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Upcycling Biodegradable PVA/Starch Film to a Bacterial Biopigment and Biopolymer. Polymers (Basel) 2021; 13:polym13213692. [PMID: 34771249 PMCID: PMC8588134 DOI: 10.3390/polym13213692] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/15/2021] [Accepted: 10/21/2021] [Indexed: 12/01/2022] Open
Abstract
Meeting the challenge of circularity for plastics requires amenability to repurposing post-use, as equivalent or upcycled products. In a compelling advancement, complete circularity for a biodegradable polyvinyl alcohol/thermoplastic starch (PVA/TPS) food packaging film was demonstrated by bioconversion to high-market-value biopigments and polyhydroxybutyrate (PHB) polyesters. The PVA/TPS film mechanical properties (tensile strength (σu), 22.2 ± 4.3 MPa; strain at break (εu), 325 ± 73%; and Young’s modulus (E), 53–250 MPa) compared closely with low-density polyethylene (LDPE) grades used for food packaging. Strong solubility of the PVA/TPS film in water was a pertinent feature, facilitating suitability as a carbon source for bioprocessing and microbial degradation. Biodegradability of the film with greater than 50% weight loss occurred within 30 days of incubation at 37 °C in a model compost. Up to 22% of the PVA/TPS film substrate conversion to biomass was achieved using three bacterial strains, Ralstonia eutropha H16 (Cupriavidus necator ATCC 17699), Streptomyces sp. JS520, and Bacillus subtilis ATCC6633. For the first time, production of the valuable biopigment (undecylprodigiosin) by Streptomyces sp. JS520 of 5.3 mg/mL and the production of PHB biopolymer at 7.8% of cell dry weight by Ralstonia eutropha H16 from this substrate were reported. This low-energy, low-carbon post-use PVA/TPS film upcycling model approach to plastic circularity demonstrates marked progress in the quest for sustainable and circular plastic solutions.
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Wu C, Li F, Yi S, Ge F. Genetically engineered microbial remediation of soils co-contaminated by heavy metals and polycyclic aromatic hydrocarbons: Advances and ecological risk assessment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 296:113185. [PMID: 34243092 DOI: 10.1016/j.jenvman.2021.113185] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 06/08/2021] [Accepted: 06/27/2021] [Indexed: 06/13/2023]
Abstract
Soils contaminated with heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) have been becoming a worldwide concerned environmental problem because of threatening public healthy via food chain exposure. Thus soils polluted by HMs and PAHs need to be remediated urgently. Physical and chemical remediation methods usually have some disadvantages, e.g., cost-expensiveness and incomplete removal, easily causing secondary pollution, which are hence not environmental-friendly. Conventional microbial approaches are mostly used to treat a single contaminant in soils and lack high efficiency and specificity for combined contaminants. Genetically engineered microorganisms (GEMs) have emerged as a desired requirement of higher bioremediation efficiency for soils polluted with HMs and PAHs and environmental sustainability, which can provide a more eco-friendly and cost-effective strategy in comparison with some conventional techniques. This review comments the recent advances about successful bioremediation techniques and approaches for soil contaminated with HMs and/or PAHs by GEMs, and discusses some challenges in the simultaneous removal of HMs and PAHs from soil by designing multi-functional genetic engineering microorganisms (MFGEMs), such as improvement of higher efficiency, strict environmental conditions, and possible ecological risks. Also, the modern biotechnological techniques and approaches in improving the ability of microbial enzymes to effectively degrade combined contaminants at a faster rate are introduced, such as reasonable gene editing, metabolic pathway modification, and protoplast fusion. Although MFGEMs are more potent than the native microbes and can quickly adapt to combined contaminants in soils, the ecological risk of MFGEMs needs to be evaluated under a regulatory, safety, or costs benefit-driving system in a way of stratified regulation. Nevertheless, the innovation of genetic engineering to produce MFGEMs should be inspired for the welfare of successful bioremediation for soils contaminated with HMs and PAHs but it must be supervised by the public, authorities, and laws.
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Affiliation(s)
- Chen Wu
- College of Environment Science and Resources, Xiangtan University, Xiangtan, 411105, PR China; Hunan Engineering Laboratory for High Efficiency Purification Technology and Its Application on Complex Heavy Metal Wastewater Treatment, Xiangtan, 411105, PR China
| | - Feng Li
- College of Environment Science and Resources, Xiangtan University, Xiangtan, 411105, PR China; Hunan Engineering Laboratory for High Efficiency Purification Technology and Its Application on Complex Heavy Metal Wastewater Treatment, Xiangtan, 411105, PR China.
| | - Shengwei Yi
- College of Environment Science and Resources, Xiangtan University, Xiangtan, 411105, PR China; Hunan Engineering Laboratory for High Efficiency Purification Technology and Its Application on Complex Heavy Metal Wastewater Treatment, Xiangtan, 411105, PR China
| | - Fei Ge
- College of Environment Science and Resources, Xiangtan University, Xiangtan, 411105, PR China; Hunan Engineering Laboratory for High Efficiency Purification Technology and Its Application on Complex Heavy Metal Wastewater Treatment, Xiangtan, 411105, PR China
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Yu F, Zhao X, Wang Z, Liu L, Yi L, Zhou J, Li J, Chen J, Du G. Recent Advances in the Physicochemical Properties and Biotechnological Application of Vitreoscilla Hemoglobin. Microorganisms 2021; 9:microorganisms9071455. [PMID: 34361891 PMCID: PMC8306070 DOI: 10.3390/microorganisms9071455] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Revised: 07/03/2021] [Accepted: 07/04/2021] [Indexed: 11/16/2022] Open
Abstract
Vitreoscilla hemoglobin (VHb), the first discovered bacterial hemoglobin, is a soluble heme-binding protein with a faster rate of oxygen dissociation. Since it can enhance cell growth, product synthesis and stress tolerance, VHb has been widely applied in the field of metabolic engineering for microorganisms, plants, and animals. Especially under oxygen-limited conditions, VHb can interact with terminal oxidase to deliver enough oxygen to achieve high-cell-density fermentation. In recent years, with the development of bioinformatics and synthetic biology, several novel physicochemical properties and metabolic regulatory effects of VHb have been discovered and numerous strategies have been utilized to enhance the expression level of VHb in various hosts, which greatly promotes its applications in biotechnology. Thus, in this review, the new information regarding structure, function and expressional tactics for VHb is summarized to understand its latest applications and pave a new way for the future improvement of biosynthesis for other products.
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Affiliation(s)
- Fei Yu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China; (F.Y.); (Z.W.); (L.L.); (L.Y.); (J.Z.); (J.L.); (J.C.)
- Science Center for Future Foods, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
| | - Xinrui Zhao
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China; (F.Y.); (Z.W.); (L.L.); (L.Y.); (J.Z.); (J.L.); (J.C.)
- Science Center for Future Foods, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
- Correspondence: (X.Z.); (G.D.)
| | - Ziwei Wang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China; (F.Y.); (Z.W.); (L.L.); (L.Y.); (J.Z.); (J.L.); (J.C.)
| | - Luyao Liu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China; (F.Y.); (Z.W.); (L.L.); (L.Y.); (J.Z.); (J.L.); (J.C.)
| | - Lingfeng Yi
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China; (F.Y.); (Z.W.); (L.L.); (L.Y.); (J.Z.); (J.L.); (J.C.)
| | - Jingwen Zhou
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China; (F.Y.); (Z.W.); (L.L.); (L.Y.); (J.Z.); (J.L.); (J.C.)
- Science Center for Future Foods, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
| | - Jianghua Li
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China; (F.Y.); (Z.W.); (L.L.); (L.Y.); (J.Z.); (J.L.); (J.C.)
- Science Center for Future Foods, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
| | - Jian Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China; (F.Y.); (Z.W.); (L.L.); (L.Y.); (J.Z.); (J.L.); (J.C.)
- Science Center for Future Foods, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
| | - Guocheng Du
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China; (F.Y.); (Z.W.); (L.L.); (L.Y.); (J.Z.); (J.L.); (J.C.)
- Science Center for Future Foods, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China
- Correspondence: (X.Z.); (G.D.)
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Microbial cell factories for the production of polyhydroxyalkanoates. Essays Biochem 2021; 65:337-353. [PMID: 34132340 DOI: 10.1042/ebc20200142] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 05/14/2021] [Accepted: 05/26/2021] [Indexed: 12/20/2022]
Abstract
Pollution caused by persistent petro-plastics is the most pressing problem currently, with 8 million tons of plastic waste dumped annually in the oceans. Plastic waste management is not systematized in many countries, because it is laborious and expensive with secondary pollution hazards. Bioplastics, synthesized by microorganisms, are viable alternatives to petrochemical-based thermoplastics due to their biodegradable nature. Polyhydroxyalkanoates (PHAs) are a structurally and functionally diverse group of storage polymers synthesized by many microorganisms, including bacteria and Archaea. Some of the most important PHA accumulating bacteria include Cupriavidus necator, Burkholderia sacchari, Pseudomonas sp., Bacillus sp., recombinant Escherichia coli, and certain halophilic extremophiles. PHAs are synthesized by specialized PHA polymerases with assorted monomers derived from the cellular metabolite pool. In the natural cycle of cellular growth, PHAs are depolymerized by the native host for carbon and energy. The presence of these microbial PHA depolymerases in natural niches is responsible for the degradation of bioplastics. Polyhydroxybutyrate (PHB) is the most common PHA with desirable thermoplastic-like properties. PHAs have widespread applications in various industries including biomedicine, fine chemicals production, drug delivery, packaging, and agriculture. This review provides the updated knowledge on the metabolic pathways for PHAs synthesis in bacteria, and the major microbial hosts for PHAs production. Yeasts are presented as a potential candidate for industrial PHAs production, with their high amenability to genetic engineering and the availability of industrial-scale technology. The major bottlenecks in the commercialization of PHAs as an alternative for plastics and future perspectives are also critically discussed.
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