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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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2
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Grzesiak J, Gawor J, Rogala MM, Kouřilová X, Obruča S. Genetic engineering of low-temperature polyhydroxyalkanoate production by Acidovorax sp. A1169, a psychrophile isolated from a subglacial outflow. Extremophiles 2023; 27:25. [PMID: 37709928 PMCID: PMC10501959 DOI: 10.1007/s00792-023-01311-5] [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: 07/24/2023] [Accepted: 08/24/2023] [Indexed: 09/16/2023]
Abstract
In recent years, extremophilic microorganisms have been employed as producers of the microbial bioplastics polyhydroxyalkanoates (PHA), which are of great biotechnological value. Nevertheless, cold-loving or psychrophilic (cryophilic) bacteria have been neglected in this regard. Here, we present an investigation of the Arctic glacier-derived PHA producer Acidovorax sp. A1169. Biolog GEN III Microplates were used as a screening tool to identify the most suitable carbon substrate concerning PHA synthesis. The strain produced homopolymer poly(3-hydroxybutyrate) (PHB) most efficiently (2 g/L) at a temperature of 15 °C when supplied with fructose or mannitol as carbon sources with a substantial decrease of PHB biosynthesis at 17.5 °C. The PHB yield did not increase considerably or even decreased when carbon source concentration exceeded 10 g/L hinting that the strain is oligotrophic in nature. The strain was also capable of introducing 3-hydroxyvalerate (3HV) into the polymer structure, which is known to improve PHA thermoplastic properties. This is the first investigation providing insight into a PHA biosynthesis process by means of a true psychrophile, offering guidelines on polar-region bacteria cultivation, production of PHA and also on the methodology for genetic engineering of psychrophiles.
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Affiliation(s)
- Jakub Grzesiak
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5A, 02-106, Warsaw, Poland.
| | - Jan Gawor
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5A, 02-106, Warsaw, Poland
| | - Małgorzata Marta Rogala
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5A, 02-106, Warsaw, Poland
| | - Xenie Kouřilová
- Department of Food Chemistry and Biotechnology, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00, Brno, Czech Republic
| | - Stanislav Obruča
- Department of Food Chemistry and Biotechnology, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00, Brno, Czech Republic
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Park H, Faulkner M, Toogood HS, Chen GQ, Scrutton N. Online Omics Platform Expedites Industrial Application of Halomonas bluephagenesis TD1.0. Bioinform Biol Insights 2023; 17:11779322231171779. [PMID: 37200674 PMCID: PMC10185862 DOI: 10.1177/11779322231171779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 04/07/2023] [Indexed: 05/20/2023] Open
Abstract
Multi-omic data mining has the potential to revolutionize synthetic biology especially in non-model organisms that have not been extensively studied. However, tangible engineering direction from computational analysis remains elusive due to the interpretability of large datasets and the difficulty in analysis for non-experts. New omics data are generated faster than our ability to use and analyse results effectively, resulting in strain development that proceeds through classic methods of trial-and-error without insight into complex cell dynamics. Here we introduce a user-friendly, interactive website hosting multi-omics data. Importantly, this new platform allows non-experts to explore questions in an industrially important chassis whose cellular dynamics are still largely unknown. The web platform contains a complete KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment analysis derived from principal components analysis, an interactive bio-cluster heatmap analysis of genes, and the Halomonas TD1.0 genome-scale metabolic (GEM) model. As a case study of the effectiveness of this platform, we applied unsupervised machine learning to determine key differences between Halomonas bluephagenesis TD1.0 cultivated under varied conditions. Specifically, cell motility and flagella apparatus are identified to drive energy expenditure usage at different osmolarities, and predictions were verified experimentally using microscopy and fluorescence labelled flagella staining. As more omics projects are completed, this landing page will facilitate exploration and targeted engineering efforts of the robust, industrial chassis H bluephagenesis for researchers without extensive bioinformatics background.
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Affiliation(s)
- Helen Park
- EPSRC/BBSRC Future Biomanufacturing Research Hub and BBSRC Synthetic Biology Research Centre SYNBIOCHEM, Manchester Institute of Biotechnology and Department of Chemistry, The University of Manchester, Manchester, UK
- Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, China
| | - Matthew Faulkner
- EPSRC/BBSRC Future Biomanufacturing Research Hub and BBSRC Synthetic Biology Research Centre SYNBIOCHEM, Manchester Institute of Biotechnology and Department of Chemistry, The University of Manchester, Manchester, UK
| | - Helen S Toogood
- EPSRC/BBSRC Future Biomanufacturing Research Hub and BBSRC Synthetic Biology Research Centre SYNBIOCHEM, Manchester Institute of Biotechnology and Department of Chemistry, The University of Manchester, Manchester, UK
| | - Guo-Qiang Chen
- Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, China
| | - Nigel Scrutton
- EPSRC/BBSRC Future Biomanufacturing Research Hub and BBSRC Synthetic Biology Research Centre SYNBIOCHEM, Manchester Institute of Biotechnology and Department of Chemistry, The University of Manchester, Manchester, UK
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Ye JW, Lin YN, Yi XQ, Yu ZX, Liu X, Chen GQ. Synthetic biology of extremophiles: a new wave of biomanufacturing. Trends Biotechnol 2023; 41:342-357. [PMID: 36535816 DOI: 10.1016/j.tibtech.2022.11.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/12/2022] [Accepted: 11/25/2022] [Indexed: 12/23/2022]
Abstract
Microbial biomanufacturing, powered by the advances of synthetic biology, has attracted growing interest for the production of diverse products. In contrast to conventional microbes, extremophiles have shown better performance for low-cost production owing to their outstanding growth and synthesis capacity under stress conditions, allowing unsterilized fermentation processes. We review increasing numbers of products already manufactured utilizing extremophiles in recent years. In addition, genetic parts, molecular tools, and manipulation approaches for extremophile engineering are also summarized, and challenges and opportunities are predicted for non-conventional chassis. Next-generation industrial biotechnology (NGIB) based on engineered extremophiles promises to simplify biomanufacturing processes and achieve open and continuous fermentation, without sterilization, and utilizing low-cost substrates, making NGIB an attractive green process for sustainable manufacturing.
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Affiliation(s)
- Jian-Wen Ye
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China; Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China; Guangdong Research Center of Industrial Enzyme and Green Manufacturing Technology, School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Yi-Na Lin
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China; Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China; Guangdong Research Center of Industrial Enzyme and Green Manufacturing Technology, School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Xue-Qing Yi
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zhuo-Xuan Yu
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Xu Liu
- PhaBuilder Biotech Company, Shunyi District, Zhaoquan Ying, Beijing 101309, China
| | - Guo-Qiang Chen
- School of Life Sciences, Tsinghua University, Beijing 100084, China; Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China; Ministry of Education (MOE) Laboratory of Industrial Biocatalysis, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Center for Life Sciences, Beijing, China.
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Li J, Chen JN, Peng ZX, Chen NB, Liu CB, Zhang P, Zhang X, Chen GQ. Multifunctional Electrospinning Polyhydroxyalkanoate Fibrous Scaffolds with Antibacterial and Angiogenesis Effects for Accelerating Wound Healing. ACS APPLIED MATERIALS & INTERFACES 2023; 15:364-377. [PMID: 36577512 DOI: 10.1021/acsami.2c16905] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
To treat large-scale wounds or chronic ulcers, it is highly desirable to develop multifunctional wound dressings that integrate antibacterial and angiogenic properties. While many biomaterials have been fabricated as wound dressings for skin regeneration, few reports have addressed the issue of complete skin regeneration due to the lack of vasculature and hair follicles. Herein, an instructive poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB) fibrous wound dressing that integrates an antibacterial ciprofloxacin (CIP) and pro-angiogenic dimethyloxalylglycine (DMOG) is successfully prepared via electrospinning. The resultant dressings exhibit suitable flexibility with tensile strength and elongation at break up to 4.08 ± 0.18 MPa and 354.8 ± 18.4%, respectively. The in vitro results revealed that the groups of P34HB/CIP/DMOG dressings presented excellent biocompatibility on cell proliferation and significantly promote the spread and migration of L929 cells in both transwell and scratch assays. Capillary-like tube formation is also significantly enhanced in the P34HB/CIP/DMOG group dressings. Additionally, dressings from the P34HB/CIP and P34HB/CIP/DMOG groups show a broad spectrum of antimicrobial action against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. In vivo studies further demonstrated that the prepared dressings in the P34HB/CIP/DMOG group not only improved wound closure, increased re-epithelialization and collagen formation, as well as reduced inflammatory response but also increased angiogenesis and remodeling, resulting in complete skin regeneration and hair follicles. Collectively, this work provides a simple but efficient approach for the design of a versatile wound dressing with the potential to have a synergistic effect on the rapid stimulation of angiogenesis as well as antibacterial activity in full-thickness skin repair.
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Affiliation(s)
- Jian Li
- Shenzhen Engineering Research Center for Medical Bioactive Materials, Center for Translational Medicine Research & Development, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong 518055, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiang-Nan Chen
- School of Life Sciences, Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zi-Xin Peng
- Shenzhen Engineering Research Center for Medical Bioactive Materials, Center for Translational Medicine Research & Development, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong 518055, China
| | - Ning-Bo Chen
- Research Laboratory for Biomedical Optics and Molecular Imaging, CAS Key Laboratory of Health Informatics, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Cheng-Bo Liu
- Research Laboratory for Biomedical Optics and Molecular Imaging, CAS Key Laboratory of Health Informatics, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Peng Zhang
- Shenzhen Engineering Research Center for Medical Bioactive Materials, Center for Translational Medicine Research & Development, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong 518055, China
| | - Xu Zhang
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
- Key Laboratory of Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
| | - Guo-Qiang Chen
- School of Life Sciences, Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing 100084, China
- Key Laboratory of Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
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Feng J, Li C, He H, Xu S, Wang X, Chen K. Construction of cell factory through combinatorial metabolic engineering for efficient production of itaconic acid. Microb Cell Fact 2022; 21:275. [PMID: 36577997 PMCID: PMC9798595 DOI: 10.1186/s12934-022-02001-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 12/17/2022] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Itaconic acid, an unsaturated C5 dicarbonic acid, has significant market demand and prospects. It has numerous biological functions, such as anti-cancer, anti-inflammatory, and anti-oxidative in medicine, and is an essential renewable platform chemical in industry. However, the development of industrial itaconic acid production by Aspergillus terreus, the current standard production strain, is hampered by the unavoidable drawbacks of that species. Developing a highly efficient cell factory is essential for the sustainable and green production of itaconic acid. RESULTS This study employed combinatorial engineering strategies to construct Escherichia coli cells to produce itaconic acid efficiently. Two essential genes (cis-aconitate decarboxylase (CAD) encoding gene cadA and aconitase (ACO) encoding gene acn) employed various genetic constructs and plasmid combinations to create 12 recombination E. coli strains to be screened. Among them, E. coli BL-CAC exhibited the highest titer with citrate as substrate, and the induction and reaction conditions were further systematically optimized. Subsequently, employing enzyme evolution to optimize rate-limiting enzyme CAD and synthesizing protein scaffolds to co-localize ACO and CAD were used to improve itaconic acid biosynthesis efficiency. Under the optimized reaction conditions combined with the feeding control strategy, itaconic acid titer reached 398.07 mM (51.79 g/L) of engineered E. coli BL-CAR470E-DS/A-CS cells as a catalyst with the highest specific production of 9.42 g/g(DCW) among heterologous hosts at 48 h. CONCLUSIONS The excellent catalytic performance per unit biomass shows the potential for high-efficiency production of itaconic acid and effective reduction of catalytic cell consumption. This study indicates that it is necessary to continuously explore engineering strategies to develop high-performance cell factories to break through the existing bottleneck and achieve the economical commercial production of itaconic acid.
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Affiliation(s)
- Jiao Feng
- grid.412022.70000 0000 9389 5210State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 Puzhu Road(S), Nanjing, 211816 People’s Republic of China
| | - Chunqiu Li
- grid.412022.70000 0000 9389 5210State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 Puzhu Road(S), Nanjing, 211816 People’s Republic of China
| | - Hao He
- grid.453058.f0000 0004 1755 1650Petrochemical Research Insitute of Petrochina Co. Ltd., Beijing, 102206 People’s Republic of China
| | - Sheng Xu
- grid.412022.70000 0000 9389 5210State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 Puzhu Road(S), Nanjing, 211816 People’s Republic of China
| | - Xin Wang
- grid.412022.70000 0000 9389 5210State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 Puzhu Road(S), Nanjing, 211816 People’s Republic of China
| | - Kequan Chen
- grid.412022.70000 0000 9389 5210State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 Puzhu Road(S), Nanjing, 211816 People’s Republic of China
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Zhang L, Ye JW, Zhang X, Huang W, Zhang Z, Lin Y, Zhang G, Wu F, Wang Z, Wu Q, Chen GQ. Effective production of Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) by engineered Halomonas bluephagenesis grown on glucose and 1,4-Butanediol. BIORESOURCE TECHNOLOGY 2022; 355:127270. [PMID: 35526716 DOI: 10.1016/j.biortech.2022.127270] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Revised: 05/01/2022] [Accepted: 05/02/2022] [Indexed: 06/14/2023]
Abstract
Halomonas bluephagenesis has been engineered to produce flexible copolymers P34HB or poly(3-hydroxybutyrate-co-4-hydroxybutyrate) from glucose and petrol-chemical precursor, γ-butyrolactone. Herein, gene cluster aldD-dhaT was constructed in recombinant H. bluephagenesis for catalyzing 1,4-butanediol (BDO) into 4-hydroxybutyrate, which could grow to 86 g L-1 dry cell mass (DCM) containing 77 wt% P(3HB-co-14 mol% 4HB) in 7-L bioreactor fed with glucose and bio-based BDO. Furthermore, 4HB monomer ratio could be increased to 16 mol% by engineered H. bluephagenesis TDH4-WZY254 with defected outer-membrane. Upon deletion of 4HB degradation pathway, followed by aldD-dhaT integration, the resulted H. bluephagenesis TDB141ΔAC was grown to 95 g L-1 DCM containing 79 wt% P(3HB-co-14 mol% 4HB) with a BDO conversion efficiency of 86% under fed-batch fermentation. Notably, 4HB molar ratio can be significantly improved to 21 mol% with negligible effects on cell growth and P34HB synthesis by adding 50% more BDO. This study successfully demonstrated a fully bio-based P34HB effectively produced by H. bluephagenesis.
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Affiliation(s)
- Lizhan Zhang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jian-Wen Ye
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China; Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China; Guangdong Research Center of Industrial Enzyme and Green Manufacturing Technology, School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Xu Zhang
- School of Life Sciences, Tsinghua University, Beijing 100084, China; PhaBuilder Biotech Co. Ltd., Shunyi District, Zhaoquan Ying, Beijing 101309, China; Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Wuzhe Huang
- PhaBuilder Biotech Co. Ltd., Shunyi District, Zhaoquan Ying, Beijing 101309, China
| | - Zhongnan Zhang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yina Lin
- School of Life Sciences, Tsinghua University, Beijing 100084, China; Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Center for Life Sciences, Beijing, China
| | - Ge Zhang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Fuqing Wu
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ziyu Wang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qiong Wu
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Guo-Qiang Chen
- School of Life Sciences, Tsinghua University, Beijing 100084, China; Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, China; PhaBuilder Biotech Co. Ltd., Shunyi District, Zhaoquan Ying, Beijing 101309, China; Tsinghua-Peking Center for Life Sciences, Beijing, China.
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Adaptive Laboratory Evolution of Halomonas bluephagenesis Enhances Acetate Tolerance and Utilization to Produce Poly(3-hydroxybutyrate). Molecules 2022; 27:molecules27093022. [PMID: 35566371 PMCID: PMC9103988 DOI: 10.3390/molecules27093022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/02/2022] [Accepted: 05/06/2022] [Indexed: 11/17/2022] Open
Abstract
Acetate is a promising economical and sustainable carbon source for bioproduction, but it is also a known cell-growth inhibitor. In this study, adaptive laboratory evolution (ALE) with acetate as selective pressure was applied to Halomonas bluephagenesis TD1.0, a fast-growing and contamination-resistant halophilic bacterium that naturally accumulates poly(3-hydroxybutyrate) (PHB). After 71 transfers, the evolved strain, B71, was isolated, which not only showed better fitness (in terms of tolerance and utilization rate) to high concentrations of acetate but also produced a higher PHB titer compared with the parental strain TD1.0. Subsequently, overexpression of acetyl-CoA synthetase (ACS) in B71 resulted in a further increase in acetate utilization but a decrease in PHB production. Through whole-genome resequencing, it was speculated that genetic mutations (single-nucleotide variation (SNV) in phaB, mdh, and the upstream of OmpA, and insertion of TolA) in B71 might contribute to its improved acetate adaptability and PHB production. Finally, in a 5 L bioreactor with intermittent feeding of acetic acid, B71 was able to produce 49.79 g/L PHB and 70.01 g/L dry cell mass, which were 147.2% and 82.32% higher than those of TD1.0, respectively. These results highlight that ALE provides a reliable method to harness H. bluephagenesis to metabolize acetate for the production of PHB or other high-value chemicals more efficiently.
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