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Regmi P, Knesebeck M, Boles E, Weuster-Botz D, Oreb M. A comparative analysis of NADPH supply strategies in Saccharomyces cerevisiae: Production of d-xylitol from d-xylose as a case study. Metab Eng Commun 2024; 19:e00245. [PMID: 39072283 PMCID: PMC11283233 DOI: 10.1016/j.mec.2024.e00245] [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: 05/29/2024] [Revised: 07/04/2024] [Accepted: 07/04/2024] [Indexed: 07/30/2024] Open
Abstract
Enhancing the supply of the redox cofactor NADPH in metabolically engineered cells is a critical target for optimizing the synthesis of many product classes, such as fatty acids or terpenoids. In S. cerevisiae, several successful approaches have been developed in different experimental contexts. However, their systematic comparison has not been reported. Here, we established the reduction of xylose to xylitol by an NADPH-dependent xylose reductase as a model reaction to compare the efficacy of different NADPH supply strategies in the course of a batch fermentation, in which glucose and ethanol are sequentially used as carbon sources and redox donors. We show that strains overexpressing the glucose-6-phosphate dehydrogenase Zwf1 perform best, producing up to 16.9 g L-1 xylitol from 20 g L-1 xylose in stirred tank bioreactors. The beneficial effect of increased Zwf1 activity is especially pronounced during the ethanol consumption phase. The same notion applies to the deletion of the aldehyde dehydrogenase ALD6 gene, albeit at a quantitatively lower level. Reduced expression of the phosphoglucose isomerase Pgi1 and heterologous expression of the NADP+-dependent glyceraldehyde-3-phosphate dehydrogenase Gdp1 from Kluyveromyces lactis acted synergistically with ZWF1 overexpression in the presence of glucose, but had a detrimental effect after the diauxic shift. Expression of the mitochondrial NADH kinase Pos5 in the cytosol likewise improved the production of xylitol only on glucose, but not in combination with enhanced Zwf1 activity. To demonstrate the generalizability of our observations, we show that the most promising strategies - ZWF1 overexpression and deletion of ALD6 - also improve the production of l-galactonate from d-galacturonic acid. Therefore, we expect that these findings will provide valuable guidelines for engineering not only the production of xylitol but also of diverse other pathways that require NADPH.
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Affiliation(s)
- Priti Regmi
- Goethe University Frankfurt, Faculty of Biological Sciences, Institute of Molecular Biosciences, Max-von-Laue Straße 9, 60438, Frankfurt am Main, Germany
| | - Melanie Knesebeck
- Technical University of Munich, Chair of Biochemical Engineering, Boltzmannstr. 15, 85748, Garching, Germany
| | - Eckhard Boles
- Goethe University Frankfurt, Faculty of Biological Sciences, Institute of Molecular Biosciences, Max-von-Laue Straße 9, 60438, Frankfurt am Main, Germany
| | - Dirk Weuster-Botz
- Technical University of Munich, Chair of Biochemical Engineering, Boltzmannstr. 15, 85748, Garching, Germany
| | - Mislav Oreb
- Goethe University Frankfurt, Faculty of Biological Sciences, Institute of Molecular Biosciences, Max-von-Laue Straße 9, 60438, Frankfurt am Main, Germany
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2
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Bi K, Wang W, Tang D, Shi Z, Tian S, Huang L, Lian J, Xu Z. Engineering sub-organelles of a diploid Saccharomyces cerevisiae to enhance the production of 7-dehydrocholesterol. Metab Eng 2024; 84:169-179. [PMID: 38936763 DOI: 10.1016/j.ymben.2024.06.011] [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: 04/08/2024] [Revised: 06/09/2024] [Accepted: 06/24/2024] [Indexed: 06/29/2024]
Abstract
7-Dehydrocholesterol (7-DHC) is widely present in various organisms and is an important precursor of vitamin D3. Despite significant improvements in the biosynthesis of 7-DHC, it remains insufficient to meet the industrial demands. In this study, we reported high-level production of 7-DHC in an industrial Saccharomyces cerevisiae leveraging subcellular organelles. Initially, the copy numbers of DHCR24 were increased in combination with sterol transcriptional factor engineering and rebalanced the redox power of the strain. Subsequently, the effects of compartmentalizing the post-squalene pathway in peroxisomes were validated by assembling various pathway modules in this organelle. Furthermore, several peroxisomes engineering was conducted to enhance the production of 7-DHC. Utilizing the peroxisome as a vessel for partial post-squalene pathways, the potential of yeast for 7-dehydrocholesterol production was demonstrated by achieving a 26-fold increase over the initial production level. 7-DHC titer reached 640.77 mg/L in shake flasks and 4.28 g/L in a 10 L bench-top fermentor, the highest titer ever reported. The present work lays solid foundation for large-scale and cost-effective production of 7-DHC for practical applications.
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Affiliation(s)
- Ke Bi
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China; Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Wenguang Wang
- College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Dandan Tang
- School of Pharmaceutical Science, Nanjing Tech University, Nanjing, 211816, China
| | - Zhuwei Shi
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China; Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Shuyu Tian
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China; Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Lei Huang
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China; Institute of Bioengineering, 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; Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
| | - Zhinan Xu
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China; Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
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3
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Park JK, Jeon JM, Yang YH, Kim SH, Yoon JJ. Efficient polyhydroxybutyrate production using acetate by engineered Halomonas sp. JJY01 harboring acetyl-CoA acetyltransferase. Int J Biol Macromol 2024; 254:127475. [PMID: 37863147 DOI: 10.1016/j.ijbiomac.2023.127475] [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: 08/11/2023] [Revised: 10/05/2023] [Accepted: 10/15/2023] [Indexed: 10/22/2023]
Abstract
Polyhydroxybutyrate (PHB) is a well-known biodegradable bioplastic synthesized by microorganisms and can be produced from volatile fatty acids (VFAs). Among VFAs acetate can be utilized by Halomonas sp. YLGW01 for growth and PHB production. In this study, Halomonas sp. JJY01 was developed through introducing acetyl-CoA acetyltransferase (atoAD) with LacIq-Ptrc promoter into Halomonas sp. YLGW01. The effect of expression of atoAD on acetate was investigated by comparison with acetate consumption and PHB production. Shake-flask study showed that Halomonas sp. JJY01 increased acetate consumption rate, PHB yield and PHB production (0.27 g/L/h, 0.075 g/g, 0.72 g/L) compared to the wild type strain (0.17 g/L/h, 0.016 g/g, 0.11 g/L). In 10 L fermenter scale fed-batch fermentation, the growth of Halomonas sp. JJY01 resulted in higher acetate consumption rate, PHB yield and PHB titer (0.55 g/L/h, 0.091 g/g, 4.6 g/L) than wild type strain (0.35 g/L/h, 0.067 h/h, 2.9 g/L). These findings demonstrate enhanced acetate utilization and PHB production through the introduction of atoAD in Halomonas strains.
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Affiliation(s)
- Jea-Kyung Park
- Green & Sustainable Materials R&D Department, Korea Institute of Industrial Technology (KITECH), Cheonan-si 31056, Republic of Korea; School of Civil and Environmental Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Jong-Min Jeon
- Green & Sustainable Materials R&D Department, Korea Institute of Industrial Technology (KITECH), Cheonan-si 31056, Republic of Korea
| | - Yung-Hun Yang
- Department of Biological Engineering, Konkuk University, Seoul 05029, Republic of Korea
| | - Sang-Hyoun Kim
- School of Civil and Environmental Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Jeong-Jun Yoon
- Green & Sustainable Materials R&D Department, Korea Institute of Industrial Technology (KITECH), Cheonan-si 31056, Republic of Korea.
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Wang D, He Z, Xia H, Huang J, Jin Y, Zhou R, Hao L, Wu C. Engineering acetyl-CoA metabolism to enhance stress tolerance of yeast by regulating membrane functionality. Food Microbiol 2023; 115:104322. [PMID: 37567632 DOI: 10.1016/j.fm.2023.104322] [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: 04/07/2023] [Revised: 06/06/2023] [Accepted: 06/11/2023] [Indexed: 08/13/2023]
Abstract
Zygosaccharomyces rouxii has excellent fermentation performance and good tolerance to osmotic stress. Acetyl-CoA is a crucial intermediate precursor in the central carbon metabolic pathway of yeast. This study investigated the effect of engineering acetyl-CoA metabolism on the membrane functionality and stress tolerance of yeast. Firstly, exogenous supplementation of acetyl-CoA improved the biomass and the ability of unsaturated fatty acid synthesis of Z. rouxii under salt stress. Q-PCR results suggested that the gene ACSS (coding acetyl-CoA synthetase) was significantly up-expressed. Subsequently, the gene ACSS from Z. rouxii was transformed and heterologously expressed in S. cerevisiae. The recombinant cells exhibited better multiple stress (salt, acid, heat, and cold) tolerance, higher fatty acid contents, membrane integrity, and fluidity. Our findings may provide a suitable means to enhance the stress tolerance and fermentation efficiency of yeast under harsh fermentation environments.
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Affiliation(s)
- Dingkang Wang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, 610065, China
| | - Zixi He
- College of Biomass Science and Engineering, Sichuan University, Chengdu, 610065, China
| | - Huan Xia
- College of Biomass Science and Engineering, Sichuan University, Chengdu, 610065, China
| | - Jun Huang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, 610065, China
| | - Yao Jin
- College of Biomass Science and Engineering, Sichuan University, Chengdu, 610065, China
| | - Rongqing Zhou
- College of Biomass Science and Engineering, Sichuan University, Chengdu, 610065, China
| | - Liying Hao
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
| | - Chongde Wu
- College of Biomass Science and Engineering, Sichuan University, Chengdu, 610065, China.
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5
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Thanh Ta D, Chiang CJ, Xuan Huang Z, Luu NL, Chao YP. High production of poly(3-hydroxybutyrate) in Escherichia coli using crude glycerol. BIORESOURCE TECHNOLOGY 2023:129315. [PMID: 37321309 DOI: 10.1016/j.biortech.2023.129315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/07/2023] [Accepted: 06/08/2023] [Indexed: 06/17/2023]
Abstract
Poly(3-hydroxybutyrate) (PHB) is a prominent bio-plastic and recognized as the potential replacement of petroleum-derived plastics. To make PHB cost-effective, the production scheme based on crude glycerol was developed using Escherichia coli. The heterogeneous synthesis pathway of PHB was introduced into the E. coli strain capable of efficiently utilizing glycerol. The central metabolism that links to the synthesis of acetyl-CoA and NADPH was further reprogrammed to improve the PHB production. Key genes were targeted for manipulation, involving those in glycolysis, the pentose phosphate pathway, and the tricarboxylic cycle. As a result, the engineered strain gained a 22-fold increase in the PHB titer. Finally, the fed-batch fermentation was conducted with the producer strain to give the PHB titer, content, and productivity reaching 36.3±3.0 g/L, 66.5±2.8%, and 1.2±0.1 g/L/h, respectively. The PHB yield on crude glycerol accounts for 0.3 g/g. The result indicates that the technology platform as developed is promising for the production of bio-plastics.
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Affiliation(s)
- Doan Thanh Ta
- Department of Chemical Engineering, Feng Chia University, 100 Wenhwa Road, Taichung 40724, Taiwan
| | - Chung-Jen Chiang
- Department of Medical Laboratory Science and Biotechnology, China Medical University, No. 91, Hsueh-Shih Road, Taichung 40402, Taiwan
| | - Zhu Xuan Huang
- Department of Chemical Engineering, Feng Chia University, 100 Wenhwa Road, Taichung 40724, Taiwan
| | - Nguyen Luan Luu
- Department of Chemical Engineering, Feng Chia University, 100 Wenhwa Road, Taichung 40724, Taiwan
| | - Yun-Peng Chao
- Department of Chemical Engineering, Feng Chia University, 100 Wenhwa Road, Taichung 40724, Taiwan; Department of Medical Research, China Medical University Hospital, Taichung 40447, Taiwan.
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6
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Kusmayadi A, Huang CY, Kit Leong Y, Yen HW, Lee DJ, Chang JS. Utilizing microalgal hydrolysate from dairy wastewater-grown Chlorella sorokiniana SU-1 as sustainable feedstock for polyhydroxybutyrate and β-carotene production by engineered Rhodotorula glutinis #100-29. BIORESOURCE TECHNOLOGY 2023:129277. [PMID: 37290703 DOI: 10.1016/j.biortech.2023.129277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 05/31/2023] [Accepted: 06/01/2023] [Indexed: 06/10/2023]
Abstract
The objective of this study was to explore the potential of utilizing Chlorella sorokiniana SU-1 biomass grown on dairy wastewater-amended medium as sustainable feedstock for the biosynthesis of β-carotene and polyhydroxybutyrate (PHB) by Rhodotorula glutinis #100-29. To break down the rigid cell wall, 100 g/L of microalgal biomass was treated with 3% sulfuric acid, followed by detoxification using 5% activated carbon to remove the hydroxymethylfurfural inhibitor. The detoxified microalgal hydrolysate (DMH) was used for flask-scale fermentation, which yielded a maximum biomass production of 9.22 g/L, with PHB and β-carotene concentration of 897 mg/L and 93.62 mg/L, respectively. Upon scaling up to a 5-L fermenter, the biomass concentration increased to 11.2 g/L, while the PHB and β-carotene concentrations rose to 1830 mg/L and 134.2 mg/L. These outcomes indicate that DMH holds promise as sustainable feedstock for the production of PHB and β-carotene by yeast.
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Affiliation(s)
- Adi Kusmayadi
- Department of Chemical and Materials Engineering, Tunghai University, Taichung, Taiwan
| | - Chi-Yu Huang
- Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung, Taiwan; Department of Environmental Science and Engineering, Tunghai University, Taichung, Taiwan
| | - Yoong Kit Leong
- Department of Chemical and Materials Engineering, Tunghai University, Taichung, Taiwan; Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung, Taiwan
| | - Hong-Wei Yen
- Department of Chemical and Materials Engineering, Tunghai University, Taichung, Taiwan
| | - Duu-Jong Lee
- Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tang, Hong Kong
| | - Jo-Shu Chang
- Department of Chemical and Materials Engineering, Tunghai University, Taichung, Taiwan; Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung, Taiwan; Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan; Department of Chemical Engineering and Materials Science, Yuan Ze University, Chung-Li, Taiwan.
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7
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Dinh HV, Maranas CD. Evaluating proteome allocation of Saccharomyces cerevisiae phenotypes with resource balance analysis. Metab Eng 2023; 77:242-255. [PMID: 37080482 DOI: 10.1016/j.ymben.2023.04.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/12/2023] [Accepted: 04/16/2023] [Indexed: 04/22/2023]
Abstract
Saccharomyces cerevisiae is an important model organism and a workhorse in bioproduction. Here, we reconstructed a compact and tractable genome-scale resource balance analysis (RBA) model (i.e., named scRBA) to analyze metabolic fluxes and proteome allocation in a computationally efficient manner. Resource capacity models such as scRBA provide the quantitative means to identify bottlenecks in biosynthetic pathways due to enzyme, compartment size, and/or ribosome availability limitations. ATP maintenance rate and in vivo apparent turnover numbers (kapp) were regressed from metabolic flux and protein concentration data to capture observed physiological growth yield and proteome efficiency and allocation, respectively. Estimated parameter values were found to vary with oxygen and nutrient availability. Overall, this work (i) provides condition-specific model parameters to recapitulate phenotypes corresponding to different extracellular environments, (ii) alludes to the enhancing effect of substrate channeling and post-translational activation on in vivo enzyme efficiency in glycolysis and electron transport chain, and (iii) reveals that the Crabtree effect is underpinned by specific limitations in mitochondrial proteome capacity and secondarily ribosome availability rather than overall proteome capacity.
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Affiliation(s)
- Hoang V Dinh
- Department of Chemical Engineering, Pennsylvania State University, University Park, PA, USA; Center for Advanced Bioenergy and Bioproducts Innovation, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Costas D Maranas
- Department of Chemical Engineering, Pennsylvania State University, University Park, PA, USA; Center for Advanced Bioenergy and Bioproducts Innovation, The Pennsylvania State University, University Park, PA, 16802, USA.
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Priyanka U, Lens PNL. Enhanced production of amylase, pyruvate and phenolic compounds from glucose by light-driven Aspergillus niger-CuS nanobiohybrids. JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY (OXFORD, OXFORDSHIRE : 1986) 2023; 98:602-614. [PMID: 37066082 PMCID: PMC10087041 DOI: 10.1002/jctb.7153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/29/2022] [Accepted: 06/08/2022] [Indexed: 06/19/2023]
Abstract
BACKGROUND The demand for value-added compounds such as amylase, pyruvate and phenolic compounds produced by biological methods has prompted the rapid development of advanced technologies for their enhanced production. Nanobiohybrids (NBs) make use of both the microbial properties of whole-cell microorganisms and the light-harvesting efficiency of semiconductors. Photosynthetic NBs were constructed that link the biosynthetic pathways of Aspergillus niger with CuS nanoparticles. RESULTS In this work, NB formation was confirmed by negative values of the interaction energy, i.e., 2.31 × 108 to -5.52 × 108 kJ mol-1 for CuS-Che NBs, whereas for CuS-Bio NBs the values were -2.31 × 108 to -4.62 × 108 kJ mol-1 for CuS-Bio NBs with spherical nanoparticle interaction. For CuS-Bio NBs with nanorod interaction, it ranged from -2.3 × 107 to -3.47 × 107 kJ mol-1 . Further, the morphological changes observed by scanning electron microscopy showed the presence of the elements Cu and S in the energy-dispersive X-ray spectra and the presence of CuS bonds in Fourier transform infrared spectroscopy indicate NB formation. In addition, the quenching effect in photoluminescence studies confirmed NB formation. Production yields of amylase, phenolic compounds and pyruvate amounted to 11.2 μmol L-1, 52.5 μmol L-1 and 28 nmol μL-1, respectively, in A. niger-CuS Bio NBs on the third day of incubation in the bioreactor. Moreover, A niger cells-CuS Bio NBs had amino acids and lipid yields of 6.2 mg mL-1 and 26.5 mg L-1, respectively. Furthermore, probable mechanisms for the enhanced production of amylase, pyruvate and phenolic compounds are proposed. CONCLUSION Aspergillus niger-CuS NBs were used for the production of the amylase enzyme and value-added compounds such as pyruvate and phenolic compounds. Aspergillus niger-CuS Bio NBs showed a greater efficiency compared to A. niger-CuS Che NBs as the biologically produced CuS nanoparticles had a higher compatibility with A. niger cells. © 2022 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).
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Affiliation(s)
- Uddandarao Priyanka
- Department of Microbiology and Ryan InstituteNational University of IrelandGalwayIreland
| | - Piet NL Lens
- Department of Microbiology and Ryan InstituteNational University of IrelandGalwayIreland
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Yang P, Liu W, Chen Y, Gong AD. Engineering the glyoxylate cycle for chemical bioproduction. Front Bioeng Biotechnol 2022; 10:1066651. [PMID: 36532595 PMCID: PMC9755347 DOI: 10.3389/fbioe.2022.1066651] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 11/17/2022] [Indexed: 07/24/2023] Open
Abstract
With growing concerns about environmental issues and sustainable economy, bioproduction of chemicals utilizing microbial cell factories provides an eco-friendly alternative to current petro-based processes. Creating high-performance strains (with high titer, yield, and productivity) through metabolic engineering strategies is critical for cost-competitive production. Commonly, it is inevitable to fine-tuning or rewire the endogenous or heterologous pathways in such processes. As an important pathway involved in the synthesis of many kinds of chemicals, the potential of the glyoxylate cycle in metabolic engineering has been studied extensively these years. Here, we review the metabolic regulation of the glyoxylate cycle and summarize recent achievements in microbial production of chemicals through tuning of the glyoxylate cycle, with a focus on studies implemented in model microorganisms. Also, future prospects for bioproduction of glyoxylate cycle-related chemicals are discussed.
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10
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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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11
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Zhang M, Gao Y, Yu C, Wang J, Weng K, Li Q, He Y, Guo Z, Zhang H, Huang J, Li L. Transcriptome analysis of malate-induced Schizochytrium sp. FJU-512 reveals a novel pathway for biosynthesis of docosahexaenoic acid with enhanced expression of genes responsible for acetyl-CoA and NADPH accumulation. Front Microbiol 2022; 13:1006138. [PMID: 36299719 PMCID: PMC9589357 DOI: 10.3389/fmicb.2022.1006138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 09/20/2022] [Indexed: 11/21/2022] Open
Abstract
Schizochytrium is one of the few oleaginous microalgae that produce docosahexaenoic acid (DHA)-rich lipids. In this study, global changes in gene expression levels of Schizochytrium sp. FJU-512 cultured with malate in a 15 l-bioreactor was analyzed using comparative transcriptomics. The changes were found mainly in the genes involved in oxidative phosphorylation, β-oxidation, and pentose phosphate pathways. Consequently, the global changes in genes associated with the pathways could lead to an increase in the influx throughputs of pyruvate, branched-chain amino acids, fatty acids, and vitamin B6. Our transcriptome analysis indicated pyruvate dehydrogenase E2 component and acetolactate synthase I/II/III large subunit as major contributors to acetyl-CoA biosynthesis, whereas glucose-6-phosphate dehydrogenase was indicated as the major contributor to the biosynthesis of NADPH. An increase in DHA titer of up to 22% was achieved with the addition of malate to the fed-batch culture of Schizochytrium sp. FJU-512. This study provides an alternate method to enhance DHA production in Schizochytrium sp. FJU-512 through malate induced upregulation of genes responsible for acetyl-CoA and NADPH biosynthesis.
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Affiliation(s)
- Mingliang Zhang
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
- College of Life Sciences, Fujian Normal University, Fuzhou, China
| | - YangLe Gao
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
| | - Cui Yu
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
| | - Jun Wang
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
| | - Kexin Weng
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
| | - Qin Li
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
| | - Yongjin He
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
- College of Life Sciences, Fujian Normal University, Fuzhou, China
| | - Zheng Guo
- Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark
| | - Huaidong Zhang
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
- College of Life Sciences, Fujian Normal University, Fuzhou, China
- Huaidong Zhang,
| | - Jianzhong Huang
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
- College of Life Sciences, Fujian Normal University, Fuzhou, China
| | - Li Li
- Engineering Research Center of Industrial Microbiology of Ministry of Education, Fujian Normal University, Fuzhou, China
- College of Life Sciences, Fujian Normal University, Fuzhou, China
- *Correspondence: Li Li,
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12
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Ylinen A, de Ruijter JC, Jouhten P, Penttilä M. PHB production from cellobiose with Saccharomyces cerevisiae. Microb Cell Fact 2022; 21:124. [PMID: 35729556 PMCID: PMC9210708 DOI: 10.1186/s12934-022-01845-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 06/01/2022] [Indexed: 11/10/2022] Open
Abstract
Replacement of petrochemical-based materials with microbially produced biodegradable alternatives calls for industrially attractive fermentation processes. Lignocellulosic materials offer non-edible alternatives for cultivated sugars, but require often use of expensive sugar releasing enzymes, such as β-glucosidases. These cellulose treatment costs could be reduced if microbial production hosts could use short cellodextrins such as cellobiose directly as their substrates. In this study, we demonstrate production of poly(hydroxybutyrate) (PHB) in yeast Saccharomyces cerevisiae using cellobiose as a sole carbon source. Yeast strains expressing PHB pathway genes from Cupriavidus necator and cellodextrin transporter gene CDT-1 from Neurospora crassa were complemented either with β-glucosidase gene GH1-1 from N. crassa or with cellobiose phosphorylase gene cbp from Ruminococcus flavefaciens. These cellobiose utilization routes either with Gh1-1 or Cbp enzymes differ in energetics and dynamics. However, both routes enabled higher PHB production per consumed sugar and higher PHB accumulation % of cell dry weight (CDW) than use of glucose as a carbon source. As expected, the strains with Gh1-1 consumed cellobiose faster than the strains with Cbp, both in flask and bioreactor batch cultures. In shake flasks, higher final PHB accumulation % of CDW was reached with Cbp route (10.0 ± 0.3%) than with Gh1-1 route (8.1 ± 0.2%). However, a higher PHB accumulation was achieved in better aerated and pH-controlled bioreactors, in comparison to shake flasks, and the relative performance of strains switched. In bioreactors, notable PHB accumulation levels per CDW of 13.4 ± 0.9% and 18.5 ± 3.9% were achieved with Cbp and Gh1-1 routes, respectively. The average molecular weights of accumulated PHB were similar using both routes; approximately 500 kDa and 450 kDa for strains expressing either cbp or GH1-1 genes, respectively. The formation of PHB with high molecular weights, combined with efficient cellobiose conversion, demonstrates a highly potential solution for improving attractiveness of sustainable polymer production using microbial cells.
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Affiliation(s)
- Anna Ylinen
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, 02044, Espoo, Finland.
| | - Jorg C de Ruijter
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, 02044, Espoo, Finland
| | - Paula Jouhten
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, 02044, Espoo, Finland.,Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, P.O. Box 16100, 00076, Espoo, Finland
| | - Merja Penttilä
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, 02044, Espoo, Finland.,Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, P.O. Box 16100, 00076, Espoo, Finland
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13
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Müllerová L, Marková K, Obruča S, Mravec F. Use of Flavin-Related Cellular Autofluorescence to Monitor Processes in Microbial Biotechnology. Microorganisms 2022; 10:microorganisms10061179. [PMID: 35744697 PMCID: PMC9231254 DOI: 10.3390/microorganisms10061179] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 06/06/2022] [Indexed: 11/16/2022] Open
Abstract
Cellular autofluorescence is usually considered to be a negative phenomenon because it can affect the sensitivity of fluorescence microscopic or flow cytometric assays by interfering with the signal of various fluorescent probes. Nevertheless, in our work, we adopted a different approach, and green autofluorescence induced by flavins was used as a tool to monitor fermentation employing the bacterium Cupriavidus necator. The autofluorescence was used to distinguish microbial cells from abiotic particles in flow cytometry assays, and it was also used for the determination of viability or metabolic characteristics of the microbial cells. The analyses using two complementary techniques, namely fluorescence microscopy and flow cytometry, are simple and do not require labor sample preparation. Flavins and their autofluorescence can also be used in a combination with other fluorophores when the need for multi-parametrical analyses arises, but it is wise to use dyes that do not emit a green light in order to not interfere with flavins' emission band (500-550 nm).
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14
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Metabolic Engineering Strategies for Improved Lipid Production and Cellular Physiological Responses in Yeast Saccharomyces cerevisiae. J Fungi (Basel) 2022; 8:jof8050427. [PMID: 35628683 PMCID: PMC9144191 DOI: 10.3390/jof8050427] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 04/13/2022] [Accepted: 04/18/2022] [Indexed: 02/01/2023] Open
Abstract
Microbial lipids have been a hot topic in the field of metabolic engineering and synthetic biology due to their increased market and important applications in biofuels, oleochemicals, cosmetics, etc. This review first compares the popular hosts for lipid production and explains the four modules for lipid synthesis in yeast, including the fatty acid biosynthesis module, lipid accumulation module, lipid sequestration module, and fatty acid modification module. This is followed by a summary of metabolic engineering strategies that could be used for enhancing each module for lipid production. In addition, the efforts being invested in improving the production of value-added fatty acids in engineered yeast, such as cyclopropane fatty acid, ricinoleic acid, gamma linoleic acid, EPA, and DHA, are included. A discussion is further made on the potential relationships between lipid pathway engineering and consequential changes in cellular physiological properties, such as cell membrane integrity, intracellular reactive oxygen species level, and mitochondrial membrane potential. Finally, with the rapid development of synthetic biology tools, such as CRISPR genome editing tools and machine learning models, this review proposes some future trends that could be employed to engineer yeast with enhanced intracellular lipid production while not compromising much of its cellular health.
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15
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Control of D-lactic acid content in P(LA-3HB) copolymer in the yeast Saccharomyces cerevisiae using a synthetic gene expression system. Metab Eng Commun 2022; 14:e00199. [PMID: 35571351 PMCID: PMC9095885 DOI: 10.1016/j.mec.2022.e00199] [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: 12/13/2021] [Revised: 03/26/2022] [Accepted: 04/22/2022] [Indexed: 11/22/2022] Open
Abstract
The fully biobased polyhydroxyalkanoate (PHA) polymers provide interesting alternatives for petrochemical derived plastic materials. The mechanical properties of some PHAs, including the common poly(3-hydroxybutyrate) (PHB), are limited, but tunable by addition of other monomers into the polymer chain. In this study we present a precise synthetic biology method to adjust lactate monomer fraction of a polymer by controlling the monomer formation in vivo at gene expression level, independent of cultivation conditions. We used the modified doxycycline-based Tet-On approach to adjust the expression of the stereospecific D-lactate dehydrogenase gene (ldhA) from Leuconostoc mesenteroides to control D-lactic acid formation in yeast Saccharomyces cerevisiae. The synthetic Tet-On transcription factor with a VP16 activation domain was continuously expressed and its binding to a synthetic promoter with eight transcription factor specific binding sites upstream of the ldhA gene was controlled with the doxycycline concentration in the media. The increase in doxycycline concentration correlated positively with ldhA expression, D-lactic acid production, poly(D-lactic acid) (PDLA) accumulation in vivo, and D-lactic acid content in the poly(D-lactate-co-3-hydroxybutyrate) P(LA-3HB) copolymer. We demonstrated that the D-lactic acid content of the P(LA-3HB) copolymer can be adjusted linearly from 6 mol% to 93 mol% in vivo in S. cerevisiae. These results highlight the power of controlling gene expression and monomer formation in the tuning of the polymer composition. In addition, we obtained 5.6% PDLA and 19% P(LA-3HB) of the cell dry weight (CDW), which are over two- and five-fold higher accumulation levels, respectively, than reported in the previous studies with yeast. We also compared two engineered PHA synthases and discovered that in S. cerevisiae the PHA synthase PhaC1437Ps6-19 produced P(LA-3HB) copolymers with lower D-lactic acid content, but with higher molecular weight, in comparison to the PHA synthase PhaC1Pre. P(LA-3HB) monomer structure was adjusted with controlled gene expression. Expression of D-lactate dehydrogenase (ldhA) was controlled with Tet-On approach. Lactic acid content in copolymer P(LA-3HB) was adjusted from 6 mol% up to 93 mol%. 5.6% PDLA and 19% P(LA-3HB) of cell dry weight (CDW) were obtained in S. cerevisiae. PhaC1437Ps6-19 P(LA-3HB) had lower D-lactic acid % than PhaC1Pre P(LA-3HB).
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16
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Xie X, Ding D, Bai D, Zhu Y, Sun W, Sun Y, Zhang D. Melatonin biosynthesis pathways in nature and its production in engineered microorganisms. Synth Syst Biotechnol 2022; 7:544-553. [PMID: 35087957 PMCID: PMC8761603 DOI: 10.1016/j.synbio.2021.12.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/14/2021] [Accepted: 12/24/2021] [Indexed: 12/26/2022] Open
Abstract
Melatonin is a biogenic amine that can be found in plants, animals and microorganism. The metabolic pathway of melatonin is different in various organisms, and biosynthetic endogenous melatonin acts as a molecular signal and antioxidant protection against external stress. Microbial synthesis pathways of melatonin are similar to those of animals but different from those of plants. At present, the method of using microorganism fermentation to produce melatonin is gradually prevailing, and exploring the biosynthetic pathway of melatonin to modify microorganism is becoming the mainstream, which has more advantages than traditional chemical synthesis. Here, we review recent advances in the synthesis, optimization of melatonin pathway. l-tryptophan is one of the two crucial precursors for the synthesis of melatonin, which can be produced through a four-step reaction. Enzymes involved in melatonin synthesis have low specificity and catalytic efficiency. Site-directed mutation, directed evolution or promotion of cofactor synthesis can enhance enzyme activity and increase the metabolic flow to promote microbial melatonin production. On the whole, the status and bottleneck of melatonin biosynthesis can be improved to a higher level, providing an effective reference for future microbial modification.
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Affiliation(s)
- Xiaotong Xie
- Dalian Polytechnic University, Dalian, 116000, PR China
| | - Dongqin Ding
- Tianjin Institutes of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, PR China
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, PR China
| | - Danyang Bai
- Tianjin Institutes of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, PR China
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, PR China
| | - Yaru Zhu
- Tianjin Institutes of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, PR China
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, PR China
| | - Wei Sun
- Tianjin University of science and technology, Tianjin, 300308, PR China
| | - Yumei Sun
- Dalian Polytechnic University, Dalian, 116000, PR China
- Corresponding author.
| | - Dawei Zhang
- Tianjin Institutes of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, PR China
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, PR China
- Corresponding author. Tianjin Institutes of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, PR China.
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17
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Rajesh Banu J, Ginni G, Kavitha S, Yukesh Kannah R, Kumar V, Adish Kumar S, Gunasekaran M, Tyagi VK, Kumar G. Polyhydroxyalkanoates synthesis using acidogenic fermentative effluents. Int J Biol Macromol 2021; 193:2079-2092. [PMID: 34774601 DOI: 10.1016/j.ijbiomac.2021.11.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 11/02/2021] [Accepted: 11/04/2021] [Indexed: 11/29/2022]
Abstract
Polyhydroxyalkanoates (PHA) are natural polyesters synthesized by microbes which consume excess amount of carbon and less amount of nutrients. It is biodegradable in nature, and it synthesized from renewable resources. It is considered as a future polymer, which act as an attractive replacement to petrochemical based polymers. The main hindrance to the commercial application of PHA is the high manufacturing cost. This article provides an overview of different cost-effective substrates, their characteristics and composition, major strains involved in economical production of PHA and biosynthetic pathways leading to accumulation of PHA. This review also covers the operational parameters, various fermentative modes including batch, fed-batch, repeated fed-batch and continuous fed-batch systems, along with advanced feeding strategies such as single pulse carbon feeding, feed forward control, intermittent carbon feeding, feast famine conditions to observe their effects for improving PHA synthesis and associated challenges. In addition, it also presents the economic analysis and future perspectives for the commercialization of PHA production process thereby making the process sustainable and lucrative with the possibility of commercial biomanufacturing.
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Affiliation(s)
- J Rajesh Banu
- Department of Life Sciences, Central University of Tamil Nadu, Neelakudi, Thiruvarur, Tamil Nadu 610005, India
| | - G Ginni
- Department of Civil Engineering, Amrita College of Engineering and Technology, Amritagiri, Nagercoil, Tamil Nadu, 629901, India
| | - S Kavitha
- Department of Civil Engineering, Anna University Regional Campus, Tirunelveli, Tamil Nadu, 627007, India
| | - R Yukesh Kannah
- Department of Civil Engineering, Anna University Regional Campus, Tirunelveli, Tamil Nadu, 627007, India; Department of Civil Engineering, National Institute of Technology Tiruchirappalli, Tamil Nadu, 620015, India
| | - Vinod Kumar
- School of Water, Energy and Environment, Cranfield University, Cranfield MK43 0AL, United Kingdom
| | - S Adish Kumar
- Department of Civil Engineering, Anna University Regional Campus, Tirunelveli, Tamil Nadu, 627007, India
| | - M Gunasekaran
- Department of Physics, Anna University Regional Campus, Tirunelveli, Tamil Nadu, 627007, India
| | - Vinay Kumar Tyagi
- Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee, India
| | - Gopalakrishnan Kumar
- School of Civil and Environmental Engineering, Yonsei University, Seoul 03722, Republic of Korea; Institute of Chemistry, Bioscience and Environmental Engineering, Faculty of Science and Technology, University of Stavanger, Box 8600 Forus, 4036 Stavanger, Norway.
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18
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Duran L, López JM, Avalos JL. ¡Viva la mitochondria!: harnessing yeast mitochondria for chemical production. FEMS Yeast Res 2021; 20:5863938. [PMID: 32592388 DOI: 10.1093/femsyr/foaa037] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 06/12/2020] [Indexed: 12/11/2022] Open
Abstract
The mitochondria, often referred to as the powerhouse of the cell, offer a unique physicochemical environment enriched with a distinct set of enzymes, metabolites and cofactors ready to be exploited for metabolic engineering. In this review, we discuss how the mitochondrion has been engineered in the traditional sense of metabolic engineering or completely bypassed for chemical production. We then describe the more recent approach of harnessing the mitochondria to compartmentalize engineered metabolic pathways, including for the production of alcohols, terpenoids, sterols, organic acids and other valuable products. We explain the different mechanisms by which mitochondrial compartmentalization benefits engineered metabolic pathways to boost chemical production. Finally, we discuss the key challenges that need to be overcome to expand the applicability of mitochondrial engineering and reach the full potential of this emerging field.
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Affiliation(s)
- Lisset Duran
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - José Montaño López
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - José L Avalos
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
- Andlinger Center for Energy and the Environment, Princeton University, Princeton, NJ 08544, USA
- Princeton Environmental Institute, Princeton University, Princeton, NJ 08544, USA
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19
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Gong DY, Chen XY, Guo SX, Wang BC, Li B. Recent advances and new insights in biosynthesis of dendrobine and sesquiterpenes. Appl Microbiol Biotechnol 2021; 105:6597-6606. [PMID: 34463801 DOI: 10.1007/s00253-021-11534-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 08/17/2021] [Accepted: 08/18/2021] [Indexed: 11/28/2022]
Abstract
Sesquiterpenes are one of the most diverse groups of secondary metabolites that have mainly been observed in terpenoids. It is a natural terpene containing 15 carbon atoms in the molecule and three isoprene units with chain, ring, and other skeleton structures. Sesquiterpenes have been shown to display multiple biological activities such as anti-inflammatory, anti-feedant, anti-microbial, anti-tumor, anti-malarial, and immunomodulatory properties; therefore, their therapeutic effects are essential. In order to overcome the problem of low-yielding sesquiterpene content in natural plants, regulating their biosynthetic pathways has become the focus of many researchers. In plant and microbial systems, many genetic engineering strategies have been used to elucidate biosynthetic pathways and high-level production of sesquiterpenes. Here, we will introduce the research progress and prospects of the biosynthesis of artemisinin, costunolide, parthenolide, and dendrobine. Furthermore, we explore the biosynthesis of dendrobine by evaluating whether the biosynthetic strategies of these sesquiterpene compounds can be applied to the formation of dendrobine and its intermediate compounds. KEY POINTS: • The development of synthetic biology has promoted the study of terpenoid metabolism and provided an engineering platform for the production of high-value terpenoid products. • Some possible intermediate compounds of dendrobine were screened out and the possible pathway of dendrobine biosynthesis was speculated. • The possible methods of dendrobine biosynthesis were explored and speculated.
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Affiliation(s)
- Dao-Yong Gong
- Institute of Medicinal Plant Development, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100193, People's Republic of China
- College of Bioengineering of Chongqing University, Chongqing, 400045, People's Republic of China
| | - Xing-Yue Chen
- Institute of Medicinal Plant Development, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100193, People's Republic of China
| | - Shun-Xing Guo
- Institute of Medicinal Plant Development, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100193, People's Republic of China
| | - Bo-Chu Wang
- College of Bioengineering of Chongqing University, Chongqing, 400045, People's Republic of China.
| | - Biao Li
- Institute of Medicinal Plant Development, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100193, People's Republic of China.
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20
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Ylinen A, Maaheimo H, Anghelescu-Hakala A, Penttilä M, Salusjärvi L, Toivari M. Production of D-lactic acid containing polyhydroxyalkanoate polymers in yeast Saccharomyces cerevisiae. J Ind Microbiol Biotechnol 2021; 48:6253250. [PMID: 33899921 PMCID: PMC9113173 DOI: 10.1093/jimb/kuab028] [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: 01/26/2021] [Accepted: 04/13/2021] [Indexed: 11/13/2022]
Abstract
Polyhydroxyalkanoates (PHAs) provide biodegradable and bio-based alternatives to conventional plastics. Incorporation of 2-hydroxy acid monomers into polymer, in addition to 3-hydroxy acids, offers possibility to tailor the polymer properties. In this study, poly(D-lactic acid) (PDLA) and copolymer P(LA-3HB) were produced and characterized for the first time in the yeast Saccharomyces cerevisiae. Expression of engineered PHA synthase PhaC1437Ps6–19, propionyl-CoA transferase Pct540Cp, acetyl-CoA acetyltransferase PhaA, and acetoacetyl-CoA reductase PhaB1 resulted in accumulation of 3.6% P(LA-3HB) and expression of engineered enzymes PhaC1Pre and PctMe resulted in accumulation of 0.73% PDLA of the cell dry weight (CDW). According to NMR, P(LA-3HB) contained D-lactic acid repeating sequences. For reference, expression of PhaA, PhaB1, and PHA synthase PhaC1 resulted in accumulation 11% poly(hydroxybutyrate) (PHB) of the CDW. Weight average molecular weights of these polymers were comparable to similar polymers produced by bacterial strains, 24.6, 6.3, and 1 130 kDa for P(LA-3HB), PDLA, and PHB, respectively. The results suggest that yeast, as a robust and acid tolerant industrial production organism, could be suitable for production of 2-hydroxy acid containing PHAs from sugars or from 2-hydroxy acid containing raw materials. Moreover, the wide substrate specificity of PHA synthase enzymes employed increases the possibilities for modifying copolymer properties in yeast in the future.
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Affiliation(s)
- Anna Ylinen
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, FI-02044 VTT, Espoo, Finland
| | - Hannu Maaheimo
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, FI-02044 VTT, Espoo, Finland
| | | | - Merja Penttilä
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, FI-02044 VTT, Espoo, Finland.,Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, P.O. Box 11000, FI-00076 Aalto, Espoo, Finland
| | - Laura Salusjärvi
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, FI-02044 VTT, Espoo, Finland
| | - Mervi Toivari
- VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, FI-02044 VTT, Espoo, Finland
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21
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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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22
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Enhancement of C6–C10 fatty acid ethyl esters production in Saccharomyces cerevisiae CA by metabolic engineering. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.111496] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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23
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Shi W, Li J, Chen Y, Liu X, Chen Y, Guo X, Xiao D. Metabolic Engineering of Saccharomyces cerevisiae for Ethyl Acetate Biosynthesis. ACS Synth Biol 2021; 10:495-504. [PMID: 33576609 DOI: 10.1021/acssynbio.0c00446] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Ethyl acetate can be synthesized from acetyl-CoA and ethanol via a reaction by alcohol acetyltransferases (AATase) in yeast. In order to increase the yield of acetyl-CoA, different terminators were used to optimize the expressions of acetyl-CoA synthetase (ACS1/2) and aldehyde dehydrogenase (ALD6) to increase the contents of acetyl-CoA in Saccharomyces cerevisiae. ATF1 coding AATase was coexpressed in expression cassettes of ACS1/ACS2 and ALD6 to promote the carbon flux toward ethyl acetate from acetyl-CoA. Further to improve ethyl acetate production, four heterologous AATase including HuvEAT1 (Hanseniaspora uvarum), KamEAT1 (Kluyveromyces marxianus), VAAT (wild strawberry), and AeAT9 (kiwifruit) were introduced. Subsequently mitochondrial transport and utilization of pyruvate and acetyl-CoA were impeded to increase the ethyl acetate accumulation in cytoplasm. Under the optimal fermentation conditions, the engineered strain of PGAeΔPOR2 produced 1.69 g/L ethyl acetate, which was the highest value reported to date by metabolic engineering methods.
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Affiliation(s)
- Wenqi Shi
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Jie Li
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Yanfang Chen
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Xiaohang Liu
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Yefu Chen
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Xuewu Guo
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Dongguang Xiao
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
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24
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Hitschler J, Boles E. Improving 3-methylphenol (m-cresol) production in yeast via in vivo glycosylation or methylation. FEMS Yeast Res 2020; 20:6021368. [PMID: 33330906 DOI: 10.1093/femsyr/foaa063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 12/02/2020] [Indexed: 11/15/2022] Open
Abstract
Heterologous expression of 6-methylsalicylic acid synthase (MSAS) together with 6-MSA decarboxylase enables de novo production of the platform chemical and antiseptic additive 3-methylphenol (3-MP) in the yeast Saccharomyces cerevisiae. However, toxicity of 3-MP prevents higher production levels. In this study, we evaluated in vivo detoxification strategies to overcome limitations of 3-MP production. An orcinol-O-methyltransferase from Chinese rose hybrids (OOMT2) was expressed in the 3-MP producing yeast strain to convert 3-MP to 3-methylanisole (3-MA). Together with in situ extraction by dodecane of the highly volatile 3-MA this resulted in up to 211 mg/L 3-MA (1.7 mM) accumulation. Expression of a UDP-glycosyltransferase (UGT72B27) from Vitis vinifera led to the synthesis of up to 533 mg/L 3-MP as glucoside (4.9 mM). Conversion of 3-MP to 3-MA and 3-MP glucoside was not complete. Finally, deletion of phosphoglucose isomerase PGI1 together with methylation or glycosylation and feeding a fructose/glucose mixture to redirect carbon fluxes resulted in strongly increased product titers, with up to 897 mg/L 3-MA/3-MP (9 mM) and 873 mg/L 3-MP/3-MP as glucoside (8.1 mM) compared to less than 313 mg/L (2.9 mM) product titers in the wild type controls. The results show that methylation or glycosylation are promising tools to overcome limitations in further enhancing the biotechnological production of 3-MP.
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Affiliation(s)
- Julia Hitschler
- Faculty of Biological Sciences, Institute of Molecular Biosciences, Goethe University Frankfurt, Max-von-Laue Straße 9, 60438 Frankfurt am Main, Germany
| | - Eckhard Boles
- Faculty of Biological Sciences, Institute of Molecular Biosciences, Goethe University Frankfurt, Max-von-Laue Straße 9, 60438 Frankfurt am Main, Germany
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Jawaharraj K, Shrestha N, Chilkoor G, Dhiman SS, Islam J, Gadhamshetty V. Valorization of methane from environmental engineering applications: A critical review. WATER RESEARCH 2020; 187:116400. [PMID: 32979578 DOI: 10.1016/j.watres.2020.116400] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 07/29/2020] [Accepted: 09/05/2020] [Indexed: 05/09/2023]
Abstract
Wastewater and waste management sectors alone account for 18% of the anthropogenic methane (CH4) emissions. This study presents a critical overview of methanotrophs ("methane oxidizing microorganisms") for valorizing typically discarded CH4 from environmental engineering applications, focusing on wastewater treatment plants. Methanotrophs can convert CH4 into valuable bioproducts including chemicals, biodiesel, DC electricity, polymers, and S-layers, all under ambient conditions. As discarded CH4 and its oxidation products can also be used as a carbon source in nitrification and annamox processes. Here we discuss modes of CH4 assimilation by methanotrophs in both natural and engineered systems. We also highlight the technical challenges and technological breakthroughs needed to enable targeted CH4 oxidation in wastewater treatment plants.
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Affiliation(s)
- Kalimuthu Jawaharraj
- Civil and Environmental Engineering, South Dakota Mines, Rapid City 57701, SD, United States; BuG ReMeDEE consortium, South Dakota Mines, Rapid City 57701, SD, United States
| | - Namita Shrestha
- Civil and Environmental Engineering, Rose-Hulman Institute of Technology, Terre Haute 47803, IN, United States
| | - Govinda Chilkoor
- Civil and Environmental Engineering, South Dakota Mines, Rapid City 57701, SD, United States; 2-Dimensional Materials for Biofilm Engineering Science and Technology (2DBEST) Center, South Dakota School of Mines and Technology, Rapid City 57701, SD, United States
| | - Saurabh Sudha Dhiman
- BuG ReMeDEE consortium, South Dakota Mines, Rapid City 57701, SD, United States; Biological and Chemical Engineering, South Dakota School of Mines & Technology, Rapid City 57701, SD, United States
| | - Jamil Islam
- Civil and Environmental Engineering, South Dakota Mines, Rapid City 57701, SD, United States; BuG ReMeDEE consortium, South Dakota Mines, Rapid City 57701, SD, United States
| | - Venkataramana Gadhamshetty
- Civil and Environmental Engineering, South Dakota Mines, Rapid City 57701, SD, United States; BuG ReMeDEE consortium, South Dakota Mines, Rapid City 57701, SD, United States; 2-Dimensional Materials for Biofilm Engineering Science and Technology (2DBEST) Center, South Dakota School of Mines and Technology, Rapid City 57701, SD, United States.
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Zhang Y, Su M, Qin N, Nielsen J, Liu Z. Expressing a cytosolic pyruvate dehydrogenase complex to increase free fatty acid production in Saccharomyces cerevisiae. Microb Cell Fact 2020; 19:226. [PMID: 33302960 PMCID: PMC7730738 DOI: 10.1186/s12934-020-01493-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 12/03/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Saccharomyces cerevisiae is being exploited as a cell factory to produce fatty acids and their derivatives as biofuels. Previous studies found that both precursor supply and fatty acid metabolism deregulation are essential for enhanced fatty acid synthesis. A bacterial pyruvate dehydrogenase (PDH) complex expressed in the yeast cytosol was reported to enable production of cytosolic acetyl-CoA with lower energy cost and no toxic intermediate. RESULTS Overexpression of the PDH complex significantly increased cell growth, ethanol consumption and reduced glycerol accumulation. Furthermore, to optimize the redox imbalance in production of fatty acids from glucose, two endogenous NAD+-dependent glycerol-3-phosphate dehydrogenases were deleted, and a heterologous NADP+-dependent glyceraldehyde-3-phosphate dehydrogenase was introduced. The best fatty acid producing strain PDH7 with engineering of precursor and co-factor metabolism could produce 840.5 mg/L free fatty acids (FFAs) in shake flask, which was 83.2% higher than the control strain YJZ08. Profile analysis of free fatty acid suggested the cytosolic PDH complex mainly resulted in the increases of unsaturated fatty acids (C16:1 and C18:1). CONCLUSIONS We demonstrated that cytosolic PDH pathway enabled more efficient acetyl-CoA provision with the lower ATP cost, and improved FFA production. Together with engineering of the redox factor rebalance, the cytosolic PDH pathway could achieve high level of FFA production at similar levels of other best acetyl-CoA producing pathways.
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Affiliation(s)
- Yiming Zhang
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, No.15 North Third Ring Road East, Chaoyang District, Beijing, 100029, People's Republic of China
| | - Mo Su
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, No.15 North Third Ring Road East, Chaoyang District, Beijing, 100029, People's Republic of China
| | - Ning Qin
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, No.15 North Third Ring Road East, Chaoyang District, Beijing, 100029, People's Republic of China
| | - Jens Nielsen
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, No.15 North Third Ring Road East, Chaoyang District, Beijing, 100029, People's Republic of China.,Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden.,BioInnovation Institute, Ole Maaløes Vej 3, 2200, Copenhagen N, Denmark
| | - Zihe Liu
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, No.15 North Third Ring Road East, Chaoyang District, Beijing, 100029, People's Republic of China.
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Li S, Zhang Q, Wang J, Liu Y, Zhao Y, Deng Y. Recent progress in metabolic engineering of Saccharomyces cerevisiae for the production of malonyl-CoA derivatives. J Biotechnol 2020; 325:83-90. [PMID: 33278463 DOI: 10.1016/j.jbiotec.2020.11.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 11/10/2020] [Accepted: 11/10/2020] [Indexed: 02/08/2023]
Abstract
To reduce dependence on petroleum, the biosynthesis of important chemicals from simple substrates using industrial microorganisms has attracted increased attention. Metabolic engineering of Saccharomyces cerevisiae offers a sustainable and flexible alternative for the production of various chemicals. As a key metabolic intermediate, malonyl-CoA is a precursor for many useful compounds. However, the productivity of malonyl-CoA derivatives is restricted by the low cellular level of malonyl-CoA and enzymatic performance. In this review, we focused on how to increase the intracellular malonyl-CoA level and summarize the recent advances in different metabolic engineering strategies for directing intracellular malonyl-CoA to the desired malonyl-CoA derivatives, including strengthening the malonyl-CoA supply, reducing malonyl-CoA consumption, and precisely controlling the intracellular malonyl-CoA level. These strategies provided new insights for further improving the synthesis of malonyl-CoA derivatives in microorganisms.
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Affiliation(s)
- Shiyun Li
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Qiyue Zhang
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Jing Wang
- China-Canada Joint Lab of Food Nutrition and Health (Beijing), Beijing Technology & Business University, Beijing 100048, China
| | - Yingli Liu
- China-Canada Joint Lab of Food Nutrition and Health (Beijing), Beijing Technology & Business University, Beijing 100048, China
| | - Yunying Zhao
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China.
| | - Yu Deng
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China.
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Huttanus HM, Senger RS. A synthetic biosensor to detect peroxisomal acetyl-CoA concentration for compartmentalized metabolic engineering. PeerJ 2020; 8:e9805. [PMID: 33194349 PMCID: PMC7485502 DOI: 10.7717/peerj.9805] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 08/03/2020] [Indexed: 11/20/2022] Open
Abstract
Background Sub-cellular compartmentalization is used by cells to create favorable microenvironments for various metabolic reactions. These compartments concentrate enzymes, separate competing metabolic reactions, and isolate toxic intermediates. Such advantages have been recently harnessed by metabolic engineers to improve the production of various high-value chemicals via compartmentalized metabolic engineering. However, measuring sub-cellular concentrations of key metabolites represents a grand challenge for compartmentalized metabolic engineering. Methods To this end, we developed a synthetic biosensor to measure a key metabolite, acetyl-CoA, in a representative compartment of yeast, the peroxisome. This synthetic biosensor uses enzyme re-localization via PTS1 signal peptides to construct a metabolic pathway in the peroxisome which converts acetyl-CoA to polyhydroxybutyrate (PHB) via three enzymes. The PHB is then quantified by HPLC. Results The biosensor demonstrated the difference in relative peroxisomal acetyl-CoA availability under various culture conditions and was also applied to screening a library of single knockout yeast mutants. The screening identified several mutants with drastically reduced peroxisomal acetyl-CoA and one with potentially increased levels. We expect our synthetic biosensors can be widely used to investigate sub-cellular metabolism and facilitate the “design-build-test” cycle of compartmentalized metabolic engineering.
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Affiliation(s)
- Herbert M Huttanus
- Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, United States of America
| | - Ryan S Senger
- Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, United States of America.,Department of Chemical Engineering, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, United States of America
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29
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Wu H, Li S, Ji M, Chen Q, Shi J, Blamey JM, Sun J. Improvement of polyhydroxybutyrate production by deletion of csrA in Escherichia coli. ELECTRON J BIOTECHN 2020. [DOI: 10.1016/j.ejbt.2020.04.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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30
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Chu LL, Montecillo JAV, Bae H. Recent Advances in the Metabolic Engineering of Yeasts for Ginsenoside Biosynthesis. Front Bioeng Biotechnol 2020; 8:139. [PMID: 32158753 PMCID: PMC7052115 DOI: 10.3389/fbioe.2020.00139] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 02/11/2020] [Indexed: 01/03/2023] Open
Abstract
Ginsenosides are a group of glycosylated triterpenes isolated from Panax species. Ginsenosides are promising candidates for the prevention and treatment of cancer as well as food additives. However, owing to a lack of efficient approaches for ginsenoside production from plants and chemical synthesis, ginsenosides may not yet have reached their full potential as medicinal resources. In recent years, an alternative approach for ginsenoside production has been developed using the model yeast Saccharomyces cerevisiae and non-conventional yeasts such as Yarrowia lipolytica and Pichia pastoris. In this review, various metabolic engineering strategies, including heterologous gene expression, balancing, and increasing metabolic flux, and enzyme engineering, have been described as recent advanced engineering techniques for improving ginsenoside production. Furthermore, the usefulness of a systems approach and fermentation strategy has been presented. Finally, the present challenges and future research direction for industrial cell factories have been discussed.
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Affiliation(s)
- Luan Luong Chu
- Department of Biotechnology, Yeungnam University, Gyeongsan-si, South Korea
| | | | - Hanhong Bae
- Department of Biotechnology, Yeungnam University, Gyeongsan-si, South Korea
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31
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Gao S, Lyu Y, Zeng W, Du G, Zhou J, Chen J. Efficient Biosynthesis of (2 S)-Naringenin from p-Coumaric Acid in Saccharomyces cerevisiae. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:1015-1021. [PMID: 31690080 DOI: 10.1021/acs.jafc.9b05218] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
(2S)-Naringenin, a (2S)-flavanone, is widely used in the food, chemical, and pharmaceutical industries because of its diverse physiological activities. The production of (2S)-naringenin in microorganisms provides an ideal source that reduces the cost of the flavonoid. To achieve efficient production of (2S)-naringenin in Saccharomyces cerevisiae (S. cerevisiae), we constructed a biosynthetic pathway from p-coumaric acid, a cost-effective and more efficient precursor. The (2S)-naringenin synthesis pathway genes were integrated into the yeast genome to obtain a (2S)-naringenin production strain. After gene dosage experiments, the genes negatively regulating the shikimate pathway and inefficient chalcone synthase activity were verified as factors limiting (2S)-naringenin biosynthesis. With fed-batch process optimization of the engineered strain, the titer of (2S)-naringenin reached 648.63 mg/L from 2.5 g/L p-coumaric acid. Our results indicate that the constitutive production of (2S)-naringenin from p-coumaric acid in S. cerevisiae is highly promising.
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32
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Arumugam A, Furhana Shereen M. Bioconversion of Calophyllum inophyllum oilcake for intensification of rhamnolipid and polyhydroxyalkanoates co-production by Enterobacter aerogenes. BIORESOURCE TECHNOLOGY 2020; 296:122321. [PMID: 31677405 DOI: 10.1016/j.biortech.2019.122321] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 10/20/2019] [Accepted: 10/21/2019] [Indexed: 06/10/2023]
Abstract
The biologically derived products are highly valued due to their biodegradability, low toxicity, and renewability. However, most production processes are exorbitant due to high raw material cost and the downstream processing required for product recovery and purification. Therefore, the present study utilized the low-cost lignocellulosic biomass, Calophyllum inophyllum oilcake for the simultaneous production of PHA and rhamnolipid by a facultative anaerobe Enterobacter aerogenes. Both the products are produced during the stationary phase and constitute β- hydroxyalkanoic acids, which makes it feasible for the co-production through a single fermentation process. From the batch fermentation studies, it was revealed that the under optimum condition rhamnolipid and PHA yield are 5.81 g/L and 4.2 g/L: 5%(v/v) of inoculum size, pH of 6.5, C:N ratio of 5:1 and urea are found to be the best nitrogen source for the fermentation process. Characterization studies for extracted PHA and RL was done using- FTIR, NMR and TGA analysis.
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Affiliation(s)
- A Arumugam
- School of Chemical & Biotechnology, SASTRA Deemed University, Tirumalaisamudram, Thanjavur, India.
| | - M Furhana Shereen
- School of Chemical & Biotechnology, SASTRA Deemed University, Tirumalaisamudram, Thanjavur, India
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33
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Pereira R, Vilaça P, Maia P, Nielsen J, Rocha I. Turnover Dependent Phenotypic Simulation: A Quantitative Constraint-Based Simulation Method That Accommodates All Main Strain Design Strategies. ACS Synth Biol 2019; 8:976-988. [PMID: 30925047 DOI: 10.1021/acssynbio.8b00248] [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
The uncertain relationship between genotype and phenotype can make strain engineering an arduous trial and error process. To identify promising gene targets faster, constraint-based modeling methodologies are often used, although they remain limited in their predictive power. Even though the search for gene knockouts is fairly established in constraint-based modeling, most strain design methods still model gene up/down-regulations by forcing the corresponding flux values to fixed levels without taking in consideration the availability of resources. Here, we present a constraint-based algorithm, the turnover dependent phenotypic simulation (TDPS) that quantitatively simulates phenotypes in a resource conscious manner. Unlike other available algorithms, TDPS does not force flux values and considers resource availability, using metabolite production turnovers as an indicator of metabolite abundance. TDPS can simulate up-regulation of metabolic reactions as well as the introduction of heterologous genes, alongside gene deletion and down-regulation scenarios. TDPS simulations were validated using engineered Saccharomyces cerevisiae strains available in the literature by comparing the simulated and experimental production yields of the target metabolite. For many of the strains evaluated, the experimental production yields were within the simulated intervals and the relative strain performance could be predicted with TDPS. However, the algorithm failed to predict some of the production changes observed experimentally, suggesting that further improvements are necessary. The results also showed that TDPS may be helpful in finding metabolic bottlenecks, but further experiments would be required to confirm these findings.
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Affiliation(s)
- Rui Pereira
- CEB − Centre of Biological Engineering, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal
- Department of Biology and Biological Engineering, Chalmers University of Technology, SE412 96 Gothenburg, Sweden
| | - Paulo Vilaça
- CEB − Centre of Biological Engineering, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal
- SilicoLife Lda., Rua do Canastreiro 15, 4715-387 Braga, Portugal
| | - Paulo Maia
- CEB − Centre of Biological Engineering, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal
- SilicoLife Lda., Rua do Canastreiro 15, 4715-387 Braga, Portugal
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Chalmers University of Technology, SE412 96 Gothenburg, Sweden
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Isabel Rocha
- CEB − Centre of Biological Engineering, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB-NOVA), 2775-412 Oeiras, Portugal
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Production of biofuels and chemicals from xylose using native and engineered yeast strains. Biotechnol Adv 2018; 37:271-283. [PMID: 30553928 DOI: 10.1016/j.biotechadv.2018.12.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 11/13/2018] [Accepted: 12/12/2018] [Indexed: 11/20/2022]
Abstract
Numerous metabolic engineering strategies have allowed yeasts to efficiently assimilate xylose, the second most abundant sugar component of lignocellulosic biomass. During the investigation of xylose utilization by yeasts, a global rewiring of metabolic networks upon xylose cultivation has been captured, as opposed to a pattern of glucose repression. A clear understanding of the xylose-induced metabolic reprogramming in yeast would shed light on the optimization of yeast-based bioprocesses to produce biofuels and chemicals using xylose. In this review, we delved into the characteristics of yeast xylose metabolism, and potential benefits of using xylose as a carbon source to produce various biochemicals with examples. Transcriptomic and metabolomic patterns of xylose-grown yeast cells were distinct from those on glucose-a conventional sugar of industrial biotechnology-and the gap might lead to opportunities to produce biochemicals efficiently. Indeed, limited glycolytic metabolic fluxes during xylose utilization could result in enhanced production of metabolites whose biosynthetic pathways compete for precursors with ethanol fermentation. Also, alleviation of glucose repression on cytosolic acetyl coenzyme A (acetyl-CoA) synthesis, and respiratory energy metabolism during xylose utilization enhanced production of acetyl-CoA derivatives. Consideration of singular properties of xylose metabolism, such as redox cofactor imbalance between xylose reductase and xylitol dehydrogenase, is necessary to maximize these positive xylose effects. This review argues the importance and benefits of xylose utilization as not only a way of expanding a substrate range, but also an effective environmental perturbation for the efficient production of advanced biofuels and chemicals in yeasts.
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Lian J, Mishra S, Zhao H. Recent advances in metabolic engineering of Saccharomyces cerevisiae: New tools and their applications. Metab Eng 2018; 50:85-108. [DOI: 10.1016/j.ymben.2018.04.011] [Citation(s) in RCA: 140] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 04/09/2018] [Accepted: 04/13/2018] [Indexed: 10/17/2022]
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Ji RY, Ding Y, Shi TQ, Lin L, Huang H, Gao Z, Ji XJ. Metabolic Engineering of Yeast for the Production of 3-Hydroxypropionic Acid. Front Microbiol 2018; 9:2185. [PMID: 30298059 PMCID: PMC6160737 DOI: 10.3389/fmicb.2018.02185] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 08/27/2018] [Indexed: 02/05/2023] Open
Abstract
The beta-hydroxy acid 3-hydroxypropionic acid (3-HP) is an attractive platform compound that can be used as a precursor for many commercially interesting compounds. In order to reduce the dependence on petroleum and follow sustainable development, 3-HP has been produced biologically from glucose or glycerol. It is reported that 3-HP synthesis pathways can be constructed in microbes such as Escherichia coli, Klebsiella pneumoniae and the yeast Saccharomyces cerevisiae. Among these host strains, yeast is prominent because of its strong acid tolerance which can simplify the fermentation process. Currently, the malonyl-CoA reductase pathway and the β-alanine pathway have been successfully constructed in yeast. This review presents the current developments in 3-HP production using yeast as an industrial host. By combining genome-scale engineering tools, malonyl-CoA biosensors and optimization of downstream fermentation, the production of 3-HP in yeast has the potential to reach or even exceed the yield of chemical production in the future.
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Affiliation(s)
- Rong-Yu Ji
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Ying Ding
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Tian-Qiong Shi
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Lu Lin
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing, China
| | - He Huang
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing, China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, China
- Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, China
| | - Zhen Gao
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Xiao-Jun Ji
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
- Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, China
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Peng H, He L, Haritos VS. Metabolic engineering of lipid pathways in Saccharomyces cerevisiae and staged bioprocess for enhanced lipid production and cellular physiology. J Ind Microbiol Biotechnol 2018; 45:707-717. [PMID: 29804179 DOI: 10.1007/s10295-018-2046-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Accepted: 05/17/2018] [Indexed: 01/22/2023]
Abstract
Microbially produced lipids have attracted attention for their environmental benefits and commercial value. We have combined lipid pathway engineering in Saccharomyces cerevisiae yeast with bioprocess design to improve productivity and explore barriers to enhanced lipid production. Initially, individual gene expression was tested for impact on yeast growth and lipid production. Then, two base strains were prepared for enhanced lipid accumulation and stabilization steps by combining DGAT1, ΔTgl3 with or without Atclo1, which increased lipid content ~ 1.8-fold but reduced cell viability. Next, fatty acid (FA) biosynthesis genes Ald6-SEACSL641P alone or with ACC1** were co-expressed in base strains, which significantly improved lipid content (8.0% DCW, 2.6-fold than control), but severely reduced yeast growth and cell viability. Finally, a designed two-stage process convincingly ameliorated the negative effects, resulting in normal cell growth, very high lipid productivity (307 mg/L, 4.6-fold above control) and improved cell viability.
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Affiliation(s)
- Huadong Peng
- Department of Chemical Engineering, Monash University, Wellington Road, Clayton, VIC, 3800, Australia
| | - Lizhong He
- Department of Chemical Engineering, Monash University, Wellington Road, Clayton, VIC, 3800, Australia
| | - Victoria S Haritos
- Department of Chemical Engineering, Monash University, Wellington Road, Clayton, VIC, 3800, Australia.
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Construction of Halomonas bluephagenesis capable of high cell density growth for efficient PHA production. Appl Microbiol Biotechnol 2018; 102:4499-4510. [DOI: 10.1007/s00253-018-8931-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 03/07/2018] [Accepted: 03/10/2018] [Indexed: 12/13/2022]
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39
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Fathima AM, Chuang D, Laviña WA, Liao J, Putri SP, Fukusaki E. Iterative cycle of widely targeted metabolic profiling for the improvement of 1-butanol titer and productivity in Synechococcus elongatus. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:188. [PMID: 30002728 PMCID: PMC6036673 DOI: 10.1186/s13068-018-1187-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 06/25/2018] [Indexed: 05/09/2023]
Abstract
BACKGROUND Metabolomics is the comprehensive study of metabolites that can demonstrate the downstream effects of gene and protein regulation, arguably representing the closest correlation with phenotypic features. Hence, metabolomics-driven approach offers an effective way to facilitate strain improvement. Previously, targeted metabolomics on the 1-butanol-producing cyanobacterial strain Synechococcus elongatus BUOHSE has revealed the reduction step from butanoyl-CoA to butanal, catalyzed by CoA-acylating propionaldehyde dehydrogenase (PduP), as a rate-limiting step in the CoA-dependent pathway. Moreover, an increase in acetyl-CoA synthesis rate was also observed in this strain, by which the increased rate of release of CoA from butanoyl-CoA was used to enhance formation of acetyl-CoA to feed into the pathway. RESULTS In the present study, a new strain (DC7) with an improved activity of PduP enzyme, was constructed using BUOHSE as the background strain. DC7 showed a 33% increase in 1-butanol production compared to BUOHSE. For a deeper understanding of the metabolic state of DC7, widely targeted metabolomics approach using ion-pair reversed-phase LC/MS was performed. Results showed a decreased level of butanoyl-CoA and an increased level of acetyl-CoA in DC7 compared to BUOHSE. This served as an indication that the previous bottleneck has been solved and free CoA regeneration increased upon the improvement of the PduP enzyme. In order to utilize the enhanced levels of acetyl-CoA in DC7 for 1-butanol production, overexpression of acetyl-CoA carboxylase (ACCase) in DC7 was performed by inserting the gene encoding an ACCase subunit from Yarrowia lipolytica into the aldA site. The resulting strain, named DC11, was able to reach a production titer of 418.7 mg/L in 6 days, compared to DC7 that approached a similar titer in 12 days. A maximum productivity of 117 mg/L/day was achieved between days 4 and 5 in DC11. CONCLUSIONS In this study, the iterative cycle of genetic modification based on insights from metabolomics successfully resulted in the highest reported 1-butanol productivity for engineered Synechococcus elongatus PCC 7942.
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Affiliation(s)
- Artnice Mega Fathima
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 Japan
| | - Derrick Chuang
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, 5531 Boelter Hall, 420 Westwood Plaza, Los Angeles, CA 90095 USA
| | - Walter Alvarez Laviña
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 Japan
- Microbiology Division, Institute of Biological Sciences, University of the Philippines Los, Banos, 4031 Philippines
| | - James Liao
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, 5531 Boelter Hall, 420 Westwood Plaza, Los Angeles, CA 90095 USA
| | - Sastia Prama Putri
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 Japan
| | - Eiichiro Fukusaki
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 Japan
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40
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Portugal-Nunes DJ, Pawar SS, Lidén G, Gorwa-Grauslund MF. Effect of nitrogen availability on the poly-3-D-hydroxybutyrate accumulation by engineered Saccharomyces cerevisiae. AMB Express 2017; 7:35. [PMID: 28176283 PMCID: PMC5296263 DOI: 10.1186/s13568-017-0335-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 01/30/2017] [Indexed: 12/04/2022] Open
Abstract
Poly-3-d-hydroxybutyrate (or PHB) is a polyester which can be used in the production of biodegradable plastics from renewable resources. It is naturally produced by several bacteria as a response to nutrient starvation in the excess of a carbon source. The yeast Saccharomyces cerevisiae could be an alternative production host as it offers good inhibitor tolerance towards weak acids and phenolic compounds and does not depolymerize the produced PHB. As nitrogen limitation is known to boost the accumulation of PHB in bacteria, the present study aimed at investigating the effect of nitrogen availability on PHB accumulation in two recombinant S. cerevisiae strains harboring different xylose consuming and PHB producing pathways: TMB4443 expressing an NADPH-dependent acetoacetyl-CoA reductase and a wild-type S. stipitis XR with preferential use of NADPH and TMB4425 which expresses an NADH-dependent acetoacetyl-CoA reductase and a mutated XR with a balanced affinity for NADPH/NADH. TMB4443 accumulated most PHB under aerobic conditions and with glucose as sole carbon source, whereas the highest PHB concentrations were obtained with TMB4425 under anaerobic conditions and xylose as carbon source. In both cases, the highest PHB contents were obtained with high availability of nitrogen. The major impact of nitrogen availability was observed in TMB4425, where a 2.7-fold increase in PHB content was obtained. In contrast to what was observed in natural PHB-producing bacteria, nitrogen deficiency did not improve PHB accumulation in S. cerevisiae. Instead the excess available carbon from xylose was shunted into glycogen, indicating a significant gluconeogenic activity on xylose.
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Sacomboio ENM, Kim EYS, Ruchaud Correa HL, Bonato P, de Oliveira Pedrosa F, de Souza EM, Chubatsu LS, Müller-Santos M. The transcriptional regulator NtrC controls glucose-6-phosphate dehydrogenase expression and polyhydroxybutyrate synthesis through NADPH availability in Herbaspirillum seropedicae. Sci Rep 2017; 7:13546. [PMID: 29051509 PMCID: PMC5648810 DOI: 10.1038/s41598-017-12649-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 09/12/2017] [Indexed: 11/09/2022] Open
Abstract
The NTR system is the major regulator of nitrogen metabolism in Bacteria. Despite its broad and well-known role in the assimilation, biosynthesis and recycling of nitrogenous molecules, little is known about its role in carbon metabolism. In this work, we present a new facet of the NTR system in the control of NADPH concentration and the biosynthesis of molecules dependent on reduced coenzyme in Herbaspirillum seropedicae SmR1. We demonstrated that a ntrC mutant strain accumulated high levels of polyhydroxybutyrate (PHB), reaching levels up to 2-fold higher than the parental strain. In the absence of NtrC, the activity of glucose-6-phosphate dehydrogenase (encoded by zwf) increased by 2.8-fold, consequently leading to a 2.1-fold increase in the NADPH/NADP+ ratio. A GFP fusion showed that expression of zwf is likewise controlled by NtrC. The increase in NADPH availability stimulated the production of polyhydroxybutyrate regardless the C/N ratio in the medium. The mutant ntrC was more resistant to H2O2 exposure and controlled the propagation of ROS when facing the oxidative condition, a phenotype associated with the increase in PHB content.
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Affiliation(s)
- Euclides Nenga Manuel Sacomboio
- Department of Biochemistry and Molecular Biology, Laboratory of Nitrogen Fixation, Federal University of Paraná (UFPR), Curitiba, Brazil
| | - Edson Yu Sin Kim
- Department of Biochemistry and Molecular Biology, Laboratory of Nitrogen Fixation, Federal University of Paraná (UFPR), Curitiba, Brazil
| | - Henrique Leonardo Ruchaud Correa
- Department of Biochemistry and Molecular Biology, Laboratory of Nitrogen Fixation, Federal University of Paraná (UFPR), Curitiba, Brazil
| | - Paloma Bonato
- Department of Biochemistry and Molecular Biology, Laboratory of Nitrogen Fixation, Federal University of Paraná (UFPR), Curitiba, Brazil
| | - Fabio de Oliveira Pedrosa
- Department of Biochemistry and Molecular Biology, Laboratory of Nitrogen Fixation, Federal University of Paraná (UFPR), Curitiba, Brazil
| | - Emanuel Maltempi de Souza
- Department of Biochemistry and Molecular Biology, Laboratory of Nitrogen Fixation, Federal University of Paraná (UFPR), Curitiba, Brazil
| | - Leda Satie Chubatsu
- Department of Biochemistry and Molecular Biology, Laboratory of Nitrogen Fixation, Federal University of Paraná (UFPR), Curitiba, Brazil
| | - Marcelo Müller-Santos
- Department of Biochemistry and Molecular Biology, Laboratory of Nitrogen Fixation, Federal University of Paraná (UFPR), Curitiba, Brazil.
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42
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Biernacki M, Marzec M, Roick T, Pätz R, Baronian K, Bode R, Kunze G. Enhancement of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) accumulation in Arxula adeninivorans by stabilization of production. Microb Cell Fact 2017; 16:144. [PMID: 28818103 PMCID: PMC5561651 DOI: 10.1186/s12934-017-0751-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 07/26/2017] [Indexed: 12/18/2022] Open
Abstract
Background In recent years the production of biobased biodegradable plastics has been of interest of researchers partly due to the accumulation of non-biodegradable plastics in the environment and to the opportunity for new applications. Commonly investigated are the polyhydroxyalkanoates (PHAs) poly(hydroxybutyrate) and poly(hydroxybutyrate-co-hydroxyvalerate) (PHB-V). The latter has the advantage of being tougher and less brittle. The production of these polymers in bacteria is well established but production in yeast may have some advantages, e.g. the ability to use a broad spectrum of industrial by-products as a carbon sources. Results In this study we increased the synthesis of PHB-V in the non-conventional yeast Arxula adeninivorans by stabilization of polymer accumulation via genetic modification and optimization of culture conditions. An A. adeninivorans strain with overexpressed PHA pathway genes for β-ketothiolase, acetoacetyl-CoA reductase, PHAs synthase and the phasin gene was able to accumulate an unexpectedly high level of polymer. It was found that an optimized strain cultivated in a shaking incubator is able to produce up to 52.1% of the DCW of PHB-V (10.8 g L−1) with 12.3%mol of PHV fraction. Although further optimization of cultivation conditions in a fed-batch bioreactor led to lower polymer content (15.3% of the DCW of PHB-V), the PHV fraction and total polymer level increased to 23.1%mol and 11.6 g L−1 respectively. Additionally, analysis of the product revealed that the polymer has a very low average molecular mass and unexpected melting and glass transition temperatures. Conclusions This study indicates a potential of use for the non-conventional yeast, A. adeninivorans, as an efficient producer of polyhydroxyalkanoates.
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Affiliation(s)
- Mateusz Biernacki
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, 06466, Gatersleben, Saxony-Anhalt, Germany
| | - Marek Marzec
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, 06466, Gatersleben, Saxony-Anhalt, Germany.,Faculty of Biology and Environmental Protection, University of Silesia, Jagiellonska, 28, 40-032, Katowice, Poland
| | - Thomas Roick
- Jäckering Mühlen-und Nährmittelwerke GmbH, Vorsterhauser Weg 46, 59007, Hamm, Germany
| | - Reinhard Pätz
- Division Bioprocess Technology, University of Applied Sciences, Bernburger Str. 55, 06366, Köthen, Germany
| | - Kim Baronian
- School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand
| | - Rüdiger Bode
- Institute of Microbiology, University of Greifswald, Jahnstr. 15, 17487, Greifswald, Germany
| | - Gotthard Kunze
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, 06466, Gatersleben, Saxony-Anhalt, Germany.
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43
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Improved campesterol production in engineered Yarrowia lipolytica strains. Biotechnol Lett 2017; 39:1033-1039. [DOI: 10.1007/s10529-017-2331-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 03/23/2017] [Indexed: 10/19/2022]
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44
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de Las Heras AM, Portugal-Nunes DJ, Rizza N, Sandström AG, Gorwa-Grauslund MF. Anaerobic poly-3-D-hydroxybutyrate production from xylose in recombinant Saccharomyces cerevisiae using a NADH-dependent acetoacetyl-CoA reductase. Microb Cell Fact 2016; 15:197. [PMID: 27863495 PMCID: PMC5116212 DOI: 10.1186/s12934-016-0598-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 11/10/2016] [Indexed: 11/19/2022] Open
Abstract
Background Poly-3-d-hydroxybutyrate (PHB) that is a promising precursor for bioplastic with similar physical properties as polypropylene, is naturally produced by several bacterial species. The bacterial pathway is comprised of the three enzymes β-ketothiolase, acetoacetyl-CoA reductase (AAR) and PHB synthase, which all together convert acetyl-CoA into PHB. Heterologous expression of the pathway genes from Cupriavidus necator has enabled PHB production in the yeast Saccharomyces cerevisiae from glucose as well as from xylose, after introduction of the fungal xylose utilization pathway from Scheffersomyces stipitis including xylose reductase (XR) and xylitol dehydrogenase (XDH). However PHB titers are still low. Results In this study the acetoacetyl-CoA reductase gene from C. necator (CnAAR), a NADPH-dependent enzyme, was replaced by the NADH-dependent AAR gene from Allochromatium vinosum (AvAAR) in recombinant xylose-utilizing S. cerevisiae and PHB production was compared. A. vinosum AAR was found to be active in S. cerevisiae and able to use both NADH and NADPH as cofactors. This resulted in improved PHB titers in S. cerevisiae when xylose was used as sole carbon source (5-fold in aerobic conditions and 8.4-fold under oxygen limited conditions) and PHB yields (4-fold in aerobic conditions and up to 5.6-fold under oxygen limited conditions). Moreover, the best strain was able to accumulate up to 14% of PHB per cell dry weight under fully anaerobic conditions. Conclusions This study reports a novel approach for boosting PHB accumulation in S. cerevisiae by replacement of the commonly used AAR from C. necator with the NADH-dependent alternative from A. vinosum. Additionally, to the best of our knowledge, it is the first demonstration of anaerobic PHB synthesis from xylose. Electronic supplementary material The online version of this article (doi:10.1186/s12934-016-0598-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Diogo J Portugal-Nunes
- Division of Applied Microbiology, Department of Chemistry, Lund University, PO Box 124, 221 00, Lund, Sweden
| | - Nathasha Rizza
- Division of Applied Microbiology, Department of Chemistry, Lund University, PO Box 124, 221 00, Lund, Sweden.,Vattenhallen Science Center, John Ericssons väg 1, 223 63, Lund, Sweden
| | - Anders G Sandström
- Division of Applied Microbiology, Department of Chemistry, Lund University, PO Box 124, 221 00, Lund, Sweden.,Novozymes A/S, Krogshoejvej 36, 2880, Bagsvaerd, Denmark
| | - Marie F Gorwa-Grauslund
- Division of Applied Microbiology, Department of Chemistry, Lund University, PO Box 124, 221 00, Lund, Sweden.
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45
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Li ZJ, Qiao K, Liu N, Stephanopoulos G. Engineering Yarrowia lipolytica for poly-3-hydroxybutyrate production. J Ind Microbiol Biotechnol 2016; 44:605-612. [PMID: 27826725 DOI: 10.1007/s10295-016-1864-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 10/30/2016] [Indexed: 01/12/2023]
Abstract
Strains of Yarrowia lipolytica were engineered to express the poly-3-hydroxybutyrate (PHB) biosynthetic pathway. The genes for β-ketothiolase, NADPH-dependent acetoacetyl-CoA reductase, and PHB synthase were cloned and inserted into the chromosome of Y. lipolytica. In shake flasks, the engineered strain accumulated PHB to 1.50 and 3.84% of cell dry weight in complex medium supplemented with glucose and acetate as carbon source, respectively. In fed-batch fermentation using acetate as sole carbon source, 7.35 g/l PHB (10.2% of cell dry weight) was produced. Selection of Y. lipolytica as host for PHB synthesis was motivated by the fact that this organism is a good lipids producer, which suggests robust acetyl-CoA supply also the precursor of the PHB pathway. Acetic acid could be supplied by gas fermentation, anaerobic digestion, and other low-cost supply route.
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Affiliation(s)
- Zheng-Jun Li
- Department of Chemical Engineering, Massachusetts Institute of Technology, Room 56-469, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA.,Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Kangjian Qiao
- Department of Chemical Engineering, Massachusetts Institute of Technology, Room 56-469, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Nian Liu
- Department of Chemical Engineering, Massachusetts Institute of Technology, Room 56-469, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Gregory Stephanopoulos
- Department of Chemical Engineering, Massachusetts Institute of Technology, Room 56-469, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA.
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Ghosh A, Ando D, Gin J, Runguphan W, Denby C, Wang G, Baidoo EEK, Shymansky C, Keasling JD, García Martín H. 13C Metabolic Flux Analysis for Systematic Metabolic Engineering of S. cerevisiae for Overproduction of Fatty Acids. Front Bioeng Biotechnol 2016; 4:76. [PMID: 27761435 PMCID: PMC5050205 DOI: 10.3389/fbioe.2016.00076] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 09/20/2016] [Indexed: 11/24/2022] Open
Abstract
Efficient redirection of microbial metabolism into the abundant production of desired bioproducts remains non-trivial. Here, we used flux-based modeling approaches to improve yields of fatty acids in Saccharomyces cerevisiae. We combined 13C labeling data with comprehensive genome-scale models to shed light onto microbial metabolism and improve metabolic engineering efforts. We concentrated on studying the balance of acetyl-CoA, a precursor metabolite for the biosynthesis of fatty acids. A genome-wide acetyl-CoA balance study showed ATP citrate lyase from Yarrowia lipolytica as a robust source of cytoplasmic acetyl-CoA and malate synthase as a desirable target for downregulation in terms of acetyl-CoA consumption. These genetic modifications were applied to S. cerevisiae WRY2, a strain that is capable of producing 460 mg/L of free fatty acids. With the addition of ATP citrate lyase and downregulation of malate synthase, the engineered strain produced 26% more free fatty acids. Further increases in free fatty acid production of 33% were obtained by knocking out the cytoplasmic glycerol-3-phosphate dehydrogenase, which flux analysis had shown was competing for carbon flux upstream with the carbon flux through the acetyl-CoA production pathway in the cytoplasm. In total, the genetic interventions applied in this work increased fatty acid production by ~70%.
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Affiliation(s)
- Amit Ghosh
- Lawrence Berkeley National Laboratory, Biological Systems and Engineering Division, Berkeley, CA, USA; Joint BioEnergy Institute, Emeryville, CA, USA; Indian Institute of Technology (IIT), School of Energy Science and Engineering, Kharagpur, India
| | - David Ando
- Lawrence Berkeley National Laboratory, Biological Systems and Engineering Division, Berkeley, CA, USA; Joint BioEnergy Institute, Emeryville, CA, USA
| | - Jennifer Gin
- Lawrence Berkeley National Laboratory, Biological Systems and Engineering Division, Berkeley, CA, USA; Joint BioEnergy Institute, Emeryville, CA, USA
| | - Weerawat Runguphan
- Lawrence Berkeley National Laboratory, Biological Systems and Engineering Division, Berkeley, CA, USA; Joint BioEnergy Institute, Emeryville, CA, USA; National Center for Genetic Engineering and Biotechnology (BIOTEC), Pathum Thani, Thailand
| | - Charles Denby
- Lawrence Berkeley National Laboratory, Biological Systems and Engineering Division, Berkeley, CA, USA; Joint BioEnergy Institute, Emeryville, CA, USA
| | - George Wang
- Lawrence Berkeley National Laboratory, Biological Systems and Engineering Division, Berkeley, CA, USA; Joint BioEnergy Institute, Emeryville, CA, USA
| | - Edward E K Baidoo
- Lawrence Berkeley National Laboratory, Biological Systems and Engineering Division, Berkeley, CA, USA; Joint BioEnergy Institute, Emeryville, CA, USA
| | - Chris Shymansky
- Lawrence Berkeley National Laboratory, Biological Systems and Engineering Division, Berkeley, CA, USA; Joint BioEnergy Institute, Emeryville, CA, USA; Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, CA, USA
| | - Jay D Keasling
- Lawrence Berkeley National Laboratory, Biological Systems and Engineering Division, Berkeley, CA, USA; Joint BioEnergy Institute, Emeryville, CA, USA; Department of Chemical and Biomolecular Engineering, University of California Berkeley, Berkeley, CA, USA; Department of Bioengineering, University of California Berkeley, Berkeley, CA, USA; Novo Nordisk Foundation Center for Biosustainability, Technical University Denmark, Horsholm, Denmark
| | - Héctor García Martín
- Lawrence Berkeley National Laboratory, Biological Systems and Engineering Division, Berkeley, CA, USA; Joint BioEnergy Institute, Emeryville, CA, USA
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Sekar R, Shin HD, DiChristina TJ. Direct conversion of cellulose and hemicellulose to fermentable sugars by a microbially-driven Fenton reaction. BIORESOURCE TECHNOLOGY 2016; 218:1133-1139. [PMID: 27469094 DOI: 10.1016/j.biortech.2016.07.087] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 07/18/2016] [Accepted: 07/20/2016] [Indexed: 06/06/2023]
Abstract
The aim of this work was to develop a microbially-driven Fenton reaction that fragments cellulose and hemicellulose, degrades cellodextrins and xylodextrins, and produces short-chain oligosaccharides and monomeric sugars in a single bioreactor. The lignocellulose degradation system operates at neutral pH and does not require addition of conventional lignocellulose-degrading enzymes, thus avoiding problems associated with enzyme accessibility and specificity. The ability to produce useful bioproducts was demonstrated by production of the bioplastic polyhydroxybutyrate with the xylan degradation products as starting substrate.
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Affiliation(s)
- Ramanan Sekar
- School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, United States
| | - Hyun Dong Shin
- School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, United States
| | - Thomas J DiChristina
- School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, United States.
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48
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Engineered biosynthesis of biodegradable polymers. ACTA ACUST UNITED AC 2016; 43:1037-58. [DOI: 10.1007/s10295-016-1785-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 05/21/2016] [Indexed: 10/21/2022]
Abstract
Abstract
Advances in science and technology have resulted in the rapid development of biobased plastics and the major drivers for this expansion are rising environmental concerns of plastic pollution and the depletion of fossil-fuels. This paper presents a broad view on the recent developments of three promising biobased plastics, polylactic acid (PLA), polyhydroxyalkanoate (PHA) and polybutylene succinate (PBS), well known for their biodegradability. The article discusses the natural and recombinant host organisms used for fermentative production of monomers, alternative carbon feedstocks that have been used to lower production cost, different metabolic engineering strategies used to improve product titers, various fermentation technologies employed to increase productivities and finally, the different downstream processes used for recovery and purification of the monomers and polymers.
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49
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Mitochondrial acetyl-CoA utilization pathway for terpenoid productions. Metab Eng 2016; 38:303-309. [PMID: 27471067 DOI: 10.1016/j.ymben.2016.07.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 06/25/2016] [Accepted: 07/25/2016] [Indexed: 12/26/2022]
Abstract
Acetyl-CoA is a central molecule in the metabolism of the cell, which is also a precursor molecule to a variety of value-added products such as terpenoids and fatty acid derived molecules. Considering subcellular compartmentalization of metabolic pathways allows higher concentrations of enzymes, substrates and intermediates, and bypasses competing pathways, mitochondrion-compartmentalized acetyl-CoA utilization pathways might offer better pathway activities with improved product yields. As a proof-of-concept, we sought to explore a mitochondrial farnesyl pyrophosphate (FPP) biosynthetic pathway for the biosynthesis of amorpha-4,11-diene in budding yeast. In the present study, the eight-gene FPP biosynthetic pathway was successfully expressed inside yeast mitochondria to enable high-level amorpha-4,11-diene production. In addition, we also found the mitochondrial compartment serves as a partial barrier for the translocation of FPP from mitochondria into the cytosol, which would potentially allow minimized loss of FPP to cytosolic competing pathways. To our best knowledge, this is the first report to harness yeast mitochondria for terpenoid productions from the mitochondrial acetyl-CoA pool. We envision subcellular metabolic engineering might also be employed for an efficient production of other bio-products from the mitochondrial acetyl-CoA in other eukaryotic organisms.
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50
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Lian J, Zhao H. Functional Reconstitution of a Pyruvate Dehydrogenase in the Cytosol of Saccharomyces cerevisiae through Lipoylation Machinery Engineering. ACS Synth Biol 2016; 5:689-97. [PMID: 26991359 DOI: 10.1021/acssynbio.6b00019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Acetyl-CoA is a key precursor for the biosynthesis of a wide range of fuels, chemicals, and value-added compounds, whose biosynthesis in Saccharomyces cerevisiae involves acetyl-CoA synthetase (ACS) and is energy intensive. Previous studies have demonstrated that functional expression of a pyruvate dehydrogenase (PDH) could fully replace the endogenous ACS-dependent pathway for cytosolic acetyl-CoA biosynthesis in an ATP-independent manner. However, the requirement for lipoic acid (LA) supplementation hinders its wide industrial applications. In the present study, we focus on the engineering of a de novo synthetic lipoylation machinery for reconstitution of a functional PDH in the cytosol of yeast. First, a LA auxotrophic yeast strain was constructed through the expression of the Escherichia coli PDH structural genes and a lipoate-protein ligase gene in an ACS deficient (acs1Δ acs2Δ) strain, based on which an in vivo acetyl-CoA reporter was developed for following studies. Then the de novo lipoylation pathway was reconstituted in the cytosol of yeast by coexpressing the yeast mitochondrial lipoylation machinery genes and the E. coli type II fatty acid synthase (FAS) genes. Alternatively, an unnatural de novo synthetic lipoylation pathway was constructed by combining the reversed β-oxidation pathway with an acyl-ACP synthetase gene. To the best of our knowledge, reconstitution of natural and unnatural de novo synthetic lipoylation pathways for functional expression of a PDH in the cytosol of yeast has never been reported. Our study has laid a solid foundation for the construction and further optimization of acetyl-CoA overproducing yeast strains.
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Affiliation(s)
- Jiazhang Lian
- Department of Chemical and Biomolecular Engineering,
Institute for
Genomic Biology, and ‡Departments of Chemistry, Biochemistry, and Bioengineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering,
Institute for
Genomic Biology, and ‡Departments of Chemistry, Biochemistry, and Bioengineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
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