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Gao S, Wang Y, Yuan S, Zuo J, Jin W, Shen Y, Grenier D, Yi L, Wang Y. Cooperation of quorum sensing and central carbon metabolism in the pathogenesis of Gram-positive bacteria. Microbiol Res 2024; 282:127655. [PMID: 38402726 DOI: 10.1016/j.micres.2024.127655] [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: 09/05/2023] [Revised: 01/25/2024] [Accepted: 02/17/2024] [Indexed: 02/27/2024]
Abstract
Quorum sensing (QS), an integral component of bacterial communication, is essential in coordinating the collective response of diverse bacterial pathogens. Central carbon metabolism (CCM), serving as the primary metabolic hub for substances such as sugars, lipids, and amino acids, plays a crucial role in the life cycle of bacteria. Pathogenic bacteria often utilize CCM to regulate population metabolism and enhance the synthesis of specific cellular structures, thereby facilitating in adaptation to the host microecological environment and expediting infection. Research has demonstrated that QS can both directly or indirectly affect the CCM of numerous pathogenic bacteria, thus altering their virulence and pathogenicity. This article reviews the interplay between QS and CCM in Gram-positive pathogenic bacteria, details the molecular mechanisms by which QS modulates CCM, and lays the groundwork for investigating bacterial pathogenicity and developing innovative infection treatment drugs.
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Affiliation(s)
- Shuji Gao
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471000, China; Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang 471003, China
| | - Yuxin Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471000, China; Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang 471003, China
| | - Shuo Yuan
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471000, China; Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang 471003, China
| | - Jing Zuo
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471000, China; Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang 471003, China
| | - Wenjie Jin
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471000, China; Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang 471003, China
| | - Yamin Shen
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471000, China; Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang 471003, China
| | - Daniel Grenier
- Groupe de Recherche en Écologie Buccale, Faculté de Médecine Dentaire, Université Laval, Quebec City, Quebec, Canada
| | - Li Yi
- Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang 471003, China; College of Life Science, Luoyang Normal University, Luoyang 471934, China.
| | - Yang Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471000, China; Henan Provincial Engineering Research Center for Detection and Prevention and Control of Emerging Infectious Diseases in Livestock and Poultry, Luoyang 471003, China.
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Borchert AJ, Bleem AC, Lim HG, Rychel K, Dooley KD, Kellermyer ZA, Hodges TL, Palsson BO, Beckham GT. Machine learning analysis of RB-TnSeq fitness data predicts functional gene modules in Pseudomonas putida KT2440. mSystems 2024; 9:e0094223. [PMID: 38323821 PMCID: PMC10949508 DOI: 10.1128/msystems.00942-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 01/07/2024] [Indexed: 02/08/2024] Open
Abstract
There is growing interest in engineering Pseudomonas putida KT2440 as a microbial chassis for the conversion of renewable and waste-based feedstocks, and metabolic engineering of P. putida relies on the understanding of the functional relationships between genes. In this work, independent component analysis (ICA) was applied to a compendium of existing fitness data from randomly barcoded transposon insertion sequencing (RB-TnSeq) of P. putida KT2440 grown in 179 unique experimental conditions. ICA identified 84 independent groups of genes, which we call fModules ("functional modules"), where gene members displayed shared functional influence in a specific cellular process. This machine learning-based approach both successfully recapitulated previously characterized functional relationships and established hitherto unknown associations between genes. Selected gene members from fModules for hydroxycinnamate metabolism and stress resistance, acetyl coenzyme A assimilation, and nitrogen metabolism were validated with engineered mutants of P. putida. Additionally, functional gene clusters from ICA of RB-TnSeq data sets were compared with regulatory gene clusters from prior ICA of RNAseq data sets to draw connections between gene regulation and function. Because ICA profiles the functional role of several distinct gene networks simultaneously, it can reduce the time required to annotate gene function relative to manual curation of RB-TnSeq data sets. IMPORTANCE This study demonstrates a rapid, automated approach for elucidating functional modules within complex genetic networks. While Pseudomonas putida randomly barcoded transposon insertion sequencing data were used as a proof of concept, this approach is applicable to any organism with existing functional genomics data sets and may serve as a useful tool for many valuable applications, such as guiding metabolic engineering efforts in other microbes or understanding functional relationships between virulence-associated genes in pathogenic microbes. Furthermore, this work demonstrates that comparison of data obtained from independent component analysis of transcriptomics and gene fitness datasets can elucidate regulatory-functional relationships between genes, which may have utility in a variety of applications, such as metabolic modeling, strain engineering, or identification of antimicrobial drug targets.
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Affiliation(s)
- Andrew J. Borchert
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Alissa C. Bleem
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Agile BioFoundry, Emeryville, California, USA
| | - Hyun Gyu Lim
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
- Joint BioEnergy Institute, Emeryville, California, USA
- Department of Biological Engineering, Inha University, Incheon, Korea
| | - Kevin Rychel
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
| | - Keven D. Dooley
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Agile BioFoundry, Emeryville, California, USA
| | - Zoe A. Kellermyer
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Tracy L. Hodges
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Agile BioFoundry, Emeryville, California, USA
| | - Bernhard O. Palsson
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
- Joint BioEnergy Institute, Emeryville, California, USA
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
- Department of Pediatrics, University of California, San Diego, California, USA
| | - Gregg T. Beckham
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado, USA
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
- Agile BioFoundry, Emeryville, California, USA
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3
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Sarkhel R, Priyadarsini S, Mahawar M. Nutrient limitation and oxidative stress induce the promoter of acetate operon in Salmonella Typhimurium. Arch Microbiol 2024; 206:126. [PMID: 38411730 DOI: 10.1007/s00203-024-03863-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 02/28/2024]
Abstract
Glyoxylate shunt is an important pathway for microorganisms to survive under multiple stresses. One of its enzymes, malate synthase (encoded by aceB gene), has been widely speculated for its contribution to both the pathogenesis and virulence of various microorganisms. We have previously demonstrated that malate synthase (MS) is required for the growth of Salmonella Typhimurium (S. Typhimurium) under carbon starvation and survival under oxidative stress conditions. The aceB gene is encoded by the acetate operon in S. Typhimurium. We attempted to study the activity of acetate promoter under both the starvation and oxidative stress conditions in a heterologous system. The lac promoter of the pUC19 plasmid was substituted with the putative promoter sequence of the acetate operon of S. Typhimurium upstream to the lacZ gene and transformed the vector construct into E. coli NEBα cells. The transformed cells were subjected to the stress conditions mentioned above. We observed a fourfold increase in the β-galactosidase activity in these cells resulting from the upregulation of the lacZ gene in the stationary phase of cell growth (nutrient deprived) as compared to the mid-log phase. Following exposure of stationary phase cells to hypochlorite-induced oxidative stress, we further observed a 1.6-fold increase in β galactosidase activity. These data suggest the induction of promoter activity of the acetate operon under carbon starvation and oxidative stress conditions. Thus, these observations corroborate our previous findings regarding the upregulation of aceB expression under stressful environments.
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Affiliation(s)
- Ratanti Sarkhel
- ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India
| | - Swagatika Priyadarsini
- ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India.
- Indian Council of Agricultural Research- National Research Centre on Camel, Bikaner, Rajasthan, India.
| | - Manish Mahawar
- ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India.
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Seo K, Shu W, Rückert-Reed C, Gerlinger P, Erb TJ, Kalinowski J, Wittmann C. From waste to health-supporting molecules: biosynthesis of natural products from lignin-, plastic- and seaweed-based monomers using metabolically engineered Streptomyces lividans. Microb Cell Fact 2023; 22:262. [PMID: 38114944 PMCID: PMC10731712 DOI: 10.1186/s12934-023-02266-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 12/05/2023] [Indexed: 12/21/2023] Open
Abstract
BACKGROUND Transforming waste and nonfood materials into bulk biofuels and chemicals represents a major stride in creating a sustainable bioindustry to optimize the use of resources while reducing environmental footprint. However, despite these advancements, the production of high-value natural products often continues to depend on the use of first-generation substrates, underscoring the intricate processes and specific requirements of their biosyntheses. This is also true for Streptomyces lividans, a renowned host organism celebrated for its capacity to produce a wide array of natural products, which is attributed to its genetic versatility and potent secondary metabolic activity. Given this context, it becomes imperative to assess and optimize this microorganism for the synthesis of natural products specifically from waste and nonfood substrates. RESULTS We metabolically engineered S. lividans to heterologously produce the ribosomally synthesized and posttranslationally modified peptide bottromycin, as well as the polyketide pamamycin. The modified strains successfully produced these compounds using waste and nonfood model substrates such as protocatechuate (derived from lignin), 4-hydroxybenzoate (sourced from plastic waste), and mannitol (from seaweed). Comprehensive transcriptomic and metabolomic analyses offered insights into how these substrates influenced the cellular metabolism of S. lividans. In terms of production efficiency, S. lividans showed remarkable tolerance, especially in a fed-batch process using a mineral medium containing the toxic aromatic 4-hydroxybenzoate, which led to enhanced and highly selective bottromycin production. Additionally, the strain generated a unique spectrum of pamamycins when cultured in mannitol-rich seaweed extract with no additional nutrients. CONCLUSION Our study showcases the successful production of high-value natural products based on the use of varied waste and nonfood raw materials, circumventing the reliance on costly, food-competing resources. S. lividans exhibited remarkable adaptability and resilience when grown on these diverse substrates. When cultured on aromatic compounds, it displayed a distinct array of intracellular CoA esters, presenting promising avenues for polyketide production. Future research could be focused on enhancing S. lividans substrate utilization pathways to process the intricate mixtures commonly found in waste and nonfood sources more efficiently.
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Affiliation(s)
- Kyoyoung Seo
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany
| | - Wei Shu
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany
| | | | | | - Tobias J Erb
- Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | | | - Christoph Wittmann
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany.
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5
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Zhang H, Hu W, Liu R, Bartlam M, Wang Y. Low and high nucleic acid content bacteria play discrepant roles in response to various carbon supply modes. Environ Microbiol 2023; 25:3703-3718. [PMID: 37964717 DOI: 10.1111/1462-2920.16539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 10/31/2023] [Indexed: 11/16/2023]
Abstract
Planktonic bacteria can be grouped into 'high nucleic acid content (HNA) bacteria' and 'low nucleic acid content (LNA) bacteria.' Nutrient input modes vary in environments, causing nutrient availability heterogeneity. We incubated them with equal amounts of total glucose added in a continuous/pulsed mode. The pulse-treated LNA bacteria exhibited twice the cell abundance and four times the viability of the continuous-treated LNA, while HNA did not show an adaptation to pulsed treatment. In structural equation modelling, LNA bacteria had higher path coefficients than HNA, between growth and carbon-saving metabolic pathways, intracellular ATP and the inorganic energy storage polymer, polyphosphate, indicating their low-cost growth, and flexible energy storage and utilisation. After incubation, the pulse-treated LNA bacteria contained more proteins and polysaccharides (0.00064, 0.0012 ng cell-1 ) than the continuous-treated LNA (0.00014, 0.00014 ng cell-1 ), conferring endurance and rapid response to pulses. Compared to LNA, HNA keystone taxa had stronger correlations with the primary glucose metabolism step, glycolysis, and occupied leading positions to explain the random forest model. They are essential to introduce glucose into the element cycling of the whole community under both treatments. Our work outlines a systematic bacterial response to carbon input.
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Affiliation(s)
- Hui Zhang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai International Advanced Research Institute (Shenzhen Futian), Nankai University, Tianjin, China
| | - Wei Hu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai International Advanced Research Institute (Shenzhen Futian), Nankai University, Tianjin, China
| | - Ruidan Liu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai International Advanced Research Institute (Shenzhen Futian), Nankai University, Tianjin, China
| | - Mark Bartlam
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Nankai International Advanced Research Institute (Shenzhen Futian), Nankai University, Tianjin, China
| | - Yingying Wang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai International Advanced Research Institute (Shenzhen Futian), Nankai University, Tianjin, China
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6
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Xie LY, Xu YB, Ding XQ, Liang S, Li DL, Fu AK, Zhan XA. Itaconic acid and dimethyl itaconate exert antibacterial activity in carbon-enriched environments through the TCA cycle. Biomed Pharmacother 2023; 167:115487. [PMID: 37713987 DOI: 10.1016/j.biopha.2023.115487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 09/08/2023] [Accepted: 09/08/2023] [Indexed: 09/17/2023] Open
Abstract
Itaconic acid (IA), a metabolite generated by the tricarboxylic acid (TCA) cycle in eukaryotic immune cells, and its derivative dimethyl itaconate (DI) exert antibacterial functions in intracellular environments. Previous studies suggested that IA and DI only inhibit bacterial growth in carbon-limited environments; however, whether IA and DI maintain antibacterial activity in carbon-enriched environments remains unknown. Here, IA and DI inhibited the bacteria with minimum inhibitory concentrations of 24.02 mM and 39.52 mM, respectively, in a carbon-enriched environment. The reduced bacterial pathogenicity was reflected in cell membrane integrity, motility, biofilm formation, AI-2/luxS, and virulence. Mechanistically, succinate dehydrogenase (SDH) activity and fumaric acid levels decreased in the IA and DI treatments, while isocitrate lyase (ICL) activity was upregulated. Inhibited TCA circulation was also observed through untargeted metabolomics. In addition, energy-related aspartate metabolism and lysine degradation were suppressed. In summary, these results indicated that IA and DI reduced bacterial pathogenicity while exerting antibacterial functions by inhibiting TCA circulation. This study enriches knowledge on the inhibition of bacteria by IA and DI in a carbon-mixed environment, suggesting an alternative method for treating bacterial infections by immune metabolites.
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Affiliation(s)
- L Y Xie
- Key Laboratory of Animal Nutrition and Feed in East China, Ministry of Agriculture and Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou 310058, China
| | - Y B Xu
- Key Laboratory of Animal Nutrition and Feed in East China, Ministry of Agriculture and Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou 310058, China
| | - X Q Ding
- Key Laboratory of Animal Nutrition and Feed in East China, Ministry of Agriculture and Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou 310058, China
| | - S Liang
- Key Laboratory of Animal Nutrition and Feed in East China, Ministry of Agriculture and Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou 310058, China
| | - D L Li
- Key Laboratory of Animal Nutrition and Feed in East China, Ministry of Agriculture and Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou 310058, China
| | - A K Fu
- Key Laboratory of Animal Nutrition and Feed in East China, Ministry of Agriculture and Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou 310058, China
| | - X A Zhan
- Key Laboratory of Animal Nutrition and Feed in East China, Ministry of Agriculture and Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Feed Science Institute, College of Animal Science, Zhejiang University, Hangzhou 310058, China.
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7
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Ermolaeva SA, Parfenov VA, Karalkin PA, Khesuani YD, Domnin PA. Experimentally Created Magnetic Force in Microbiological Space and On-Earth Studies: Perspectives and Restrictions. Cells 2023; 12:cells12020338. [PMID: 36672273 PMCID: PMC9856290 DOI: 10.3390/cells12020338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/07/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
Magnetic force and gravity are two fundamental forces affecting all living organisms, including bacteria. On Earth, experimentally created magnetic force can be used to counterbalance gravity and place living organisms in conditions of magnetic levitation. Under conditions of microgravity, magnetic force becomes the only force that moves bacteria, providing an acceleration towards areas of the lowest magnetic field and locking cells in this area. In this review, we consider basic principles and experimental systems used to create a magnetic force strong enough to balance gravity. Further, we describe how magnetic levitation is applied in on-Earth microbiological studies. Next, we consider bacterial behavior under combined conditions of microgravity and magnetic force onboard a spacecraft. At last, we discuss restrictions on applications of magnetic force in microbiological studies and the impact of these restrictions on biotechnological applications under space and on-Earth conditions.
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Affiliation(s)
- Svetlana A. Ermolaeva
- Gamaleya National Research Centre for Epidemiology and Microbiology, 123098 Moscow, Russia
- Correspondence: ; Tel.: +7-499-193-4375
| | - Vladislav A. Parfenov
- Institute of Metallurgy and Material Science, Russian Academy of Sciences, 119334 Moscow, Russia
- National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 115409 Moscow, Russia
| | - Pavel A. Karalkin
- Institute of Cluster Oncology, Sechenov First Moscow State Medical University, 127473 Moscow, Russia
| | | | - Pavel A. Domnin
- Gamaleya National Research Centre for Epidemiology and Microbiology, 123098 Moscow, Russia
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8
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El-Mansi M. Control of central metabolism’s architecture in Escherichia coli: An overview. Microbiol Res 2023; 266:127224. [DOI: 10.1016/j.micres.2022.127224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 10/05/2022] [Accepted: 10/05/2022] [Indexed: 11/06/2022]
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El-Mansi M, Afolabi O, Phue JN, Shiloach J. Coordinated expression of acetyl CoA synthetase and the ace operon enzymes in Escherichia coli in preparation for adaptation to acetate. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 36048631 DOI: 10.1099/mic.0.001230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Successful adaptation of Escherichia coli to constant environmental challenges demands the operation of a wide range of regulatory control mechanisms, some of which are global, while others are specific. Here, we show that the ability of acetate-negative phenotype strains of E. coli devoid of acetate kinase (AK) and phosphotransacetylase (PTA) to assimilate acetate when challenged at the end of growth on acetogenic substrates is explicable by the co-expression of acetyl CoA-synthetase (AcCoA-S) and acetate permease (AP). Furthermore, mRNA transcript measurements for acs and aceA, together with the enzymatic activities of their corresponding enzymes, acetyl CoA synthetase (AcCoA-S) and isocitrate lyase (ICL), clearly demonstrate that the expression of the two enzymes is inextricably linked and triggered in response to growth rate threshold signal (0.4 h-1± 0.03: n4). Interestingly, further restriction of carbon supply to the level of starvation led to the repression of acs (AcCoA-S), ackA (AK) and pta (PTA). Further, we provide evidence that the reaction sequence catalysed by PTA, AK and AcCoA-S is not in operation at low growth rates and that the reaction catalysed by AcCoA-S is not merely an ATP-dissipating reaction but rather advantageous, as it elevates the available free energy (ΔG°) in central metabolism. Moreover, the transcriptomic data reinforce the view that the expression of PEP carboxykinase is essential in gluconeogenic phenotypes.
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Affiliation(s)
- Mansi El-Mansi
- Bio-Ed, Scotland UK, 17/7 Watson Crescent, Edinburgh EH11 1HA, Scotland, UK.,Departments of Biochemistry, Faculty of Science, University of Africa, Toru-Orua, Bayelsa State, Nigeria
| | - Olumide Afolabi
- Departments of Biochemistry, Faculty of Science, University of Africa, Toru-Orua, Bayelsa State, Nigeria
| | - Je-Nie Phue
- Biotechnology Lab, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Building 14A, Room 173, 9000 Rockville Pike, Bethesda MD 20892, USA.,Present address: Facility for Biotechnology Resources, Centre for Biologics Evaluation and Research. U.S. Food and Drug Administration 10903 New Hampshire Ave., MD 20993, Silver Spring, USA
| | - Joseph Shiloach
- Biotechnology Lab, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Building 14A, Room 173, 9000 Rockville Pike, Bethesda MD 20892, USA
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10
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Abstract
Numerous cellular processes are regulated in response to the metabolic state of the cell. One such regulatory mechanism involves lysine acetylation, a covalent modification involving the transfer of an acetyl group from central metabolite acetyl-coenzyme A or acetyl phosphate to a lysine residue in a protein.
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11
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Bessarab I, Maszenan AM, Haryono MAS, Arumugam K, Saw NMMT, Seviour RJ, Williams RBH. Comparative Genomics of Members of the Genus Defluviicoccus With Insights Into Their Ecophysiological Importance. Front Microbiol 2022; 13:834906. [PMID: 35495637 PMCID: PMC9041414 DOI: 10.3389/fmicb.2022.834906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 02/02/2022] [Indexed: 11/23/2022] Open
Abstract
Members of the genus Defluviicoccus occur often at high abundances in activated sludge wastewater treatment plants designed to remove phosphorus, where biomass is subjected to alternating anaerobic feed/aerobic famine conditions, believed to favor the proliferation of organisms like Ca. Accumulibacter and other phosphate-accumulating organisms (PAO), and Defluviicoccus. All have a capacity to assimilate readily metabolizable substrates and store them intracellularly during the anaerobic feed stage so that under the subsequent famine aerobic stage, these can be used to synthesize polyphosphate reserves by the PAO and glycogen by Defluviicoccus. Consequently, Defluviicoccus is described as a glycogen-accumulating organism or GAO. Because they share a similar anaerobic phenotype, it has been proposed that at high Defluviicoccus abundance, the PAO are out-competed for assimilable metabolites anaerobically, and hence aerobic P removal capacity is reduced. Several Defluviicoccus whole genome sequences have been published (Ca. Defluviicoccus tetraformis, Defluviicoccus GAO-HK, and Ca. Defluviicoccus seviourii). The available genomic data of these suggest marked metabolic differences between them, some of which have ecophysiological implications. Here, we describe the whole genome sequence of the type strain Defluviicoccus vanusT, the only cultured member of this genus, and a detailed comparative re-examination of all extant Defluviicoccus genomes. Each, with one exception, which appears not to be a member of this genus, contains the genes expected of GAO members, in possessing multiple copies of those for glycogen biosynthesis and catabolism, and anaerobic polyhydroxyalkanoate (PHA) synthesis. Both 16S rRNA and genome sequence data suggest that the current recognition of four clades is insufficient to embrace their phylogenetic biodiversity, but do not support the view that they should be re-classified into families other than their existing location in the Rhodospirillaceae. As expected, considerable variations were seen in the presence and numbers of genes encoding properties associated with key substrate assimilation and metabolic pathways. Two genomes also carried the pit gene for synthesis of the low-affinity phosphate transport protein, pit, considered by many to distinguish all PAO from GAO. The data re-emphasize the risks associated with extrapolating the data generated from a single Defluviicoccus population to embrace all members of that genus.
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Affiliation(s)
- Irina Bessarab
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, Singapore
| | - Abdul Majid Maszenan
- Nanyang Environment & Water Research Institute (NEWRI), Nanyang Technological University, Singapore, Singapore.,NUS Environmental Research Institute, National University of Singapore, Singapore, Singapore
| | - Mindia A S Haryono
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, Singapore
| | - Krithika Arumugam
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Nay Min Min Thaw Saw
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Robert J Seviour
- School of Life Sciences, La Trobe University, Melbourne, VIC, Australia
| | - Rohan B H Williams
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore, Singapore
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12
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Combined Impact of Magnetic Force and Spaceflight Conditions on Escherichia Coli Physiology. Int J Mol Sci 2022; 23:ijms23031837. [PMID: 35163759 PMCID: PMC8836844 DOI: 10.3390/ijms23031837] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/26/2022] [Accepted: 02/02/2022] [Indexed: 11/16/2022] Open
Abstract
Changes in bacterial physiology caused by the combined action of the magnetic force and microgravity were studied in Escherichia coli grown using a specially developed device aboard the International Space Station. The morphology and metabolism of E. coli grown under spaceflight (SF) or combined spaceflight and magnetic force (SF + MF) conditions were compared with ground cultivated bacteria grown under standard (control) or magnetic force (MF) conditions. SF, SF + MF, and MF conditions provided the up-regulation of Ag43 auto-transporter and cell auto-aggregation. The magnetic force caused visible clustering of non-sedimenting bacteria that formed matrix-containing aggregates under SF + MF and MF conditions. Cell auto-aggregation was accompanied by up-regulation of glyoxylate shunt enzymes and Vitamin B12 transporter BtuB. Under SF and SF + MF but not MF conditions nutrition and oxygen limitations were manifested by the down-regulation of glycolysis and TCA enzymes and the up-regulation of methylglyoxal bypass. Bacteria grown under combined SF + MF conditions demonstrated superior up-regulation of enzymes of the methylglyoxal bypass and down-regulation of glycolysis and TCA enzymes compared to SF conditions, suggesting that the magnetic force strengthened the effects of microgravity on the bacterial metabolism. This strengthening appeared to be due to magnetic force-dependent bacterial clustering within a small volume that reinforced the effects of the microgravity-driven absence of convectional flows.
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13
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Shi LL, Zheng Y, Tan BW, Li ZJ. Establishment of a carbon-efficient xylulose cleavage pathway in Escherichia coli to metabolize xylose. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2021.108331] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Wang Y, Xu J, Jin Z, Xia X, Zhang W. Improvement of acetyl-CoA supply and glucose utilization increases l-leucine production in Corynebacterium glutamicum. Biotechnol J 2021; 17:e2100349. [PMID: 34870372 DOI: 10.1002/biot.202100349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 11/11/2022]
Abstract
BACKGROUND l-Leucine is one of important essential amino acids with multiple industrial applications, whose market requirements cannot be met because of the lower productivity. MAIN METHODS AND MAJOR RESULTS In this study, a strain of Corynebacterium glutamicum with high l-leucine yield was constructed to enhance its acetyl-CoA supply and glucose utilization. One copy of leuA under the control of a strong promoter was incorporated into the C. glutamicum genome. Then, acetyl-CoA supply was increased by the integration of a terminator in front of gltA and by the heterogeneous overexpression of acetyl-CoA synthetase (Acs) and deacetylase (CobB) derived from Escherichia coli. Next, the transcriptional regulator SugR was deleted to enhance glucose uptake via a phosphotransferase-mediated route. In fed-batch fermentation performed in a 5-L reactor, l-leucine production of 40.11±0.73 g/L was achieved under the optimized conditions, with the l-leucine yield and productivity of 0.25 g/g glucose and 0.59 g/L/h, respectively. CONCLUSIONS AND IMPLICATIONS These results represent a significant improvement in the l-leucine titer of C. glutamicum, indicating that the process possesses highly potential for industrial application. These strategies can be also expanded to enable the production of other value-added biochemicals derived from the intermediates of central carbon metabolism. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Yingyu Wang
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, WuXi, 214122, China.,The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, WuXi, 214122, China
| | - Jianzhong Xu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, WuXi, 214122, China
| | - Zhengyu Jin
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, WuXi, 214122, China
| | - Xiaole Xia
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, WuXi, 214122, China
| | - Weiguo Zhang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, WuXi, 214122, China
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15
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Medeiros Filho F, do Nascimento APB, Costa MDOCE, Merigueti TC, de Menezes MA, Nicolás MF, Dos Santos MT, Carvalho-Assef APD, da Silva FAB. A Systematic Strategy to Find Potential Therapeutic Targets for Pseudomonas aeruginosa Using Integrated Computational Models. Front Mol Biosci 2021; 8:728129. [PMID: 34616771 PMCID: PMC8488468 DOI: 10.3389/fmolb.2021.728129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 08/31/2021] [Indexed: 12/26/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic human pathogen that has been a constant global health problem due to its ability to cause infection at different body sites and its resistance to a broad spectrum of clinically available antibiotics. The World Health Organization classified multidrug-resistant Pseudomonas aeruginosa among the top-ranked organisms that require urgent research and development of effective therapeutic options. Several approaches have been taken to achieve these goals, but they all depend on discovering potential drug targets. The large amount of data obtained from sequencing technologies has been used to create computational models of organisms, which provide a powerful tool for better understanding their biological behavior. In the present work, we applied a method to integrate transcriptome data with genome-scale metabolic networks of Pseudomonas aeruginosa. We submitted both metabolic and integrated models to dynamic simulations and compared their performance with published in vitro growth curves. In addition, we used these models to identify potential therapeutic targets and compared the results to analyze the assumption that computational models enriched with biological measurements can provide more selective and (or) specific predictions. Our results demonstrate that dynamic simulations from integrated models result in more accurate growth curves and flux distribution more coherent with biological observations. Moreover, identifying drug targets from integrated models is more selective as the predicted genes were a subset of those found in the metabolic models. Our analysis resulted in the identification of 26 non-host homologous targets. Among them, we highlighted five top-ranked genes based on lesser conservation with the human microbiome. Overall, some of the genes identified in this work have already been proposed by different approaches and (or) are already investigated as targets to antimicrobial compounds, reinforcing the benefit of using integrated models as a starting point to selecting biologically relevant therapeutic targets.
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16
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Hwang W, Yong JH, Min KB, Lee KM, Pascoe B, Sheppard SK, Yoon SS. Genome-wide association study of signature genetic alterations among pseudomonas aeruginosa cystic fibrosis isolates. PLoS Pathog 2021; 17:e1009681. [PMID: 34161396 PMCID: PMC8274868 DOI: 10.1371/journal.ppat.1009681] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 07/12/2021] [Accepted: 05/31/2021] [Indexed: 12/18/2022] Open
Abstract
Pseudomonas aeruginosa (PA) is an opportunistic pathogen that causes diverse human infections including chronic airway infection in patients with cystic fibrosis (CF). Comparing the genomes of CF and non-CF PA isolates has great potential to identify the genetic basis of pathogenicity. To gain a deeper understanding of PA adaptation in CF airways, we performed a genome-wide association study (GWAS) on 1,001 PA genomes. Genetic variations identified among CF isolates were categorized into (i) alterations in protein-coding regions, either large- or small-scale, and (ii) polymorphic variation in intergenic regions. We introduced each CF-associated genetic alteration into the genome of PAO1, a prototype PA strain, and validated the outcomes experimentally. Loci readily mutated among CF isolates included genes encoding a probable sulfatase, a probable TonB-dependent receptor (PA2332~PA2336), L-cystine transporter (YecS, PA0313), and a probable transcriptional regulator (PA5438). A promoter region of a heme/hemoglobin uptake outer membrane receptor (PhuR, PA4710) was also different between the CF and non-CF isolate groups. Our analysis highlights ways in which the PA genome evolves to survive and persist within the context of chronic CF infection.
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Affiliation(s)
- Wontae Hwang
- Department of Microbiology and Immunology, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Sciences, Seoul, Republic of Korea
| | - Ji Hyun Yong
- Department of Microbiology and Immunology, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Sciences, Seoul, Republic of Korea
| | - Kyung Bae Min
- Department of Microbiology and Immunology, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Sciences, Seoul, Republic of Korea
| | - Kang-Mu Lee
- Department of Microbiology and Immunology, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Sciences, Seoul, Republic of Korea
| | - Ben Pascoe
- The Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, United Kingdom
| | - Samuel K Sheppard
- The Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, United Kingdom
| | - Sang Sun Yoon
- Department of Microbiology and Immunology, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Sciences, Seoul, Republic of Korea
- Institute for Immunology and Immunological Diseases, Seoul, Republic of Korea
- Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Republic of Korea
- * E-mail:
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17
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Kochanowski K, Okano H, Patsalo V, Williamson J, Sauer U, Hwa T. Global coordination of metabolic pathways in Escherichia coli by active and passive regulation. Mol Syst Biol 2021; 17:e10064. [PMID: 33852189 PMCID: PMC8045939 DOI: 10.15252/msb.202010064] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 03/04/2021] [Accepted: 03/09/2021] [Indexed: 12/15/2022] Open
Abstract
Microorganisms adjust metabolic activity to cope with diverse environments. While many studies have provided insights into how individual pathways are regulated, the mechanisms that give rise to coordinated metabolic responses are poorly understood. Here, we identify the regulatory mechanisms that coordinate catabolism and anabolism in Escherichia coli. Integrating protein, metabolite, and flux changes in genetically implemented catabolic or anabolic limitations, we show that combined global and local mechanisms coordinate the response to metabolic limitations. To allocate proteomic resources between catabolism and anabolism, E. coli uses a simple global gene regulatory program. Surprisingly, this program is largely implemented by a single transcription factor, Crp, which directly activates the expression of catabolic enzymes and indirectly reduces the expression of anabolic enzymes by passively sequestering cellular resources needed for their synthesis. However, metabolic fluxes are not controlled by this regulatory program alone; instead, fluxes are adjusted mostly through passive changes in the local metabolite concentrations. These mechanisms constitute a simple but effective global regulatory program that coarsely partitions resources between different parts of metabolism while ensuring robust coordination of individual metabolic reactions.
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Affiliation(s)
- Karl Kochanowski
- Institute of Molecular Systems BiologyETH ZurichZurichSwitzerland
- Life Science Zurich PhD Program on Systems BiologyZurichSwitzerland
| | - Hiroyuki Okano
- Department of PhysicsUniversity of California at San DiegoLa JollaCAUSA
| | - Vadim Patsalo
- Department of Integrative Structural and Computational Biology, and The Skaggs Institute for Chemical BiologyThe Scripps Research InstituteLa JollaCAUSA
| | - James Williamson
- Department of Integrative Structural and Computational Biology, and The Skaggs Institute for Chemical BiologyThe Scripps Research InstituteLa JollaCAUSA
| | - Uwe Sauer
- Institute of Molecular Systems BiologyETH ZurichZurichSwitzerland
| | - Terence Hwa
- Department of PhysicsUniversity of California at San DiegoLa JollaCAUSA
- Institute for Theoretical ScienceETH ZurichZurichSwitzerland
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18
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Millard P, Enjalbert B, Uttenweiler-Joseph S, Portais JC, Létisse F. Control and regulation of acetate overflow in Escherichia coli. eLife 2021; 10:63661. [PMID: 33720011 PMCID: PMC8021400 DOI: 10.7554/elife.63661] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 03/12/2021] [Indexed: 12/21/2022] Open
Abstract
Overflow metabolism refers to the production of seemingly wasteful by-products by cells during growth on glucose even when oxygen is abundant. Two theories have been proposed to explain acetate overflow in Escherichia coli – global control of the central metabolism and local control of the acetate pathway – but neither accounts for all observations. Here, we develop a kinetic model of E. coli metabolism that quantitatively accounts for observed behaviours and successfully predicts the response of E. coli to new perturbations. We reconcile these theories and clarify the origin, control, and regulation of the acetate flux. We also find that, in turns, acetate regulates glucose metabolism by coordinating the expression of glycolytic and TCA genes. Acetate should not be considered a wasteful end-product since it is also a co-substrate and a global regulator of glucose metabolism in E. coli. This has broad implications for our understanding of overflow metabolism.
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Affiliation(s)
- Pierre Millard
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France.,MetaToul-MetaboHUB, National Infrastructure of Metabolomics and Fluxomics, Toulouse, France
| | - Brice Enjalbert
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France
| | | | - Jean-Charles Portais
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France.,MetaToul-MetaboHUB, National Infrastructure of Metabolomics and Fluxomics, Toulouse, France.,RESTORE, Université de Toulouse, INSERM U1031, CNRS 5070, Université Toulouse III - Paul Sabatier, EFS, Toulouse, France
| | - Fabien Létisse
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France.,Université Toulouse III - Paul Sabatier, Toulouse, France
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19
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Sheng H, Jing Y, An N, Shen X, Sun X, Yan Y, Wang J, Yuan Q. Extending the shikimate pathway for microbial production of maleate from glycerol in engineered Escherichia coli. Biotechnol Bioeng 2021; 118:1840-1850. [PMID: 33512000 DOI: 10.1002/bit.27700] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 01/19/2021] [Accepted: 01/23/2021] [Indexed: 11/12/2022]
Abstract
Maleate is one of the most important unsaturated four-carbon dicarboxylic acids. It serves as an attractive building block in cosmetic, polymer, and pharmaceutical industries. Currently, industrial production of maleate relies mainly on chemical synthesis using benzene or butane as the starting materials under high temperature, which suffers from strict reaction conditions and low product yield. Here, we propose a novel biosynthetic pathway for maleate production in engineered Escherichia coli. We screened a superior salicylate 5-hydroxylase that can catalyze hydroxylation of salicylate into gentisate with high conversion rate. Then, introduction of salicylate biosynthetic pathway and gentisate ring cleavage pathway allowed the synthesis of maleate from glycerol. Further optimizations including enhancement of precursors supply, disruption of competing pathways, and construction of a pyruvate recycling system, boosted maleate titer to 2.4 ± 0.1 g/L in shake flask experiments. Subsequent scale-up biosynthesis of maleate in a 3-L bioreactor under fed-batch culture conditions enabled the production of 14.5 g/L of maleate, indicating a 268-fold improvement compared with the titer generated by the wildtype E. coli strain carrying the entire maleate biosynthetic pathway. This study provided a promising microbial platform for industrial level synthesis of maleate, and demonstrated the highest titer of maleate production in microorganisms so far.
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Affiliation(s)
- Huakang Sheng
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Yijie Jing
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Ning An
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Xiaolin Shen
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Xinxiao Sun
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Yajun Yan
- College of Engineering, The University of Georgia, Athens, Georgia, USA
| | - Jia Wang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Qipeng Yuan
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China
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20
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Miscevic D, Mao JY, Mozell B, Srirangan K, Abedi D, Moo-Young M, Chou CP. Bio-based production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with modulated monomeric fraction in Escherichia coli. Appl Microbiol Biotechnol 2021; 105:1435-1446. [PMID: 33484319 DOI: 10.1007/s00253-021-11108-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 01/10/2023]
Abstract
In this study, we applied metabolic engineering and bioprocessing strategies to enhance heterologous production of an important biodegradable copolymer, i.e., poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), with a modulated 3-hydroxyvalerate (3-HV) monomeric fraction from structurally unrelated carbon of glycerol in engineered Escherichia coli under different oxygenic conditions. We used our previously derived propanologenic (i.e., 1-propanol-producing) E. coli strain with an activated genomic Sleeping beauty mutase (Sbm) operon as a host for heterologous expression of the phaCAB operon. The 3-HV monomeric fraction was modulated by regulating dissimilated carbon flux channeling from the tricarboxylic acid (TCA) cycle into the Sbm pathway for biosynthesis of propionyl-CoA, which is a key precursor to (R)-3-hydroxyvaleryl-CoA (3-HV-CoA) monomer. The carbon flux channeling was regulated either by manipulating a selection of genes involved in the TCA cycle or varying oxygenic condition of the bacterial culture. With these consolidated strategies being implemented, we successfully achieved high-level PHBV biosynthesis with a wide range of 3-HV monomeric fraction from ~ 4 to 50 mol%, potentially enabling the fine-tuning of PHBV mechanical properties at the biosynthesis stage. We envision that similar strategies can be applied to enhance bio-based production of chemicals derived from succinyl-CoA. KEY POINTS: • TCA cycle engineering was applied to enhance 3-HV monomeric fraction in E. coli. • Effects of oxygenic conditions on 3-HV incorporation into PHBV in E. coli were investigated. • Bacterial cultivation for high-level PHBV production in engineered E. coli was performed.
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Affiliation(s)
- Dragan Miscevic
- Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada
| | - Ju-Yi Mao
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, 20224, Taiwan
| | - Bradley Mozell
- Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada
| | - Kajan Srirangan
- Biotechnology Research Institute, National Research Council of Canada, Montreal, QC, H4P 2R2, Canada
| | - Daryoush Abedi
- Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada.,Department of Drug & Food Control, Tehran University of Medical Sciences, Tehran, Iran
| | - Murray Moo-Young
- Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada
| | - C Perry Chou
- Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada.
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21
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Bacterial fitness landscapes stratify based on proteome allocation associated with discrete aero-types. PLoS Comput Biol 2021; 17:e1008596. [PMID: 33465077 PMCID: PMC7846111 DOI: 10.1371/journal.pcbi.1008596] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 01/29/2021] [Accepted: 12/01/2020] [Indexed: 11/19/2022] Open
Abstract
The fitness landscape is a concept commonly used to describe evolution towards optimal phenotypes. It can be reduced to mechanistic detail using genome-scale models (GEMs) from systems biology. We use recently developed GEMs of Metabolism and protein Expression (ME-models) to study the distribution of Escherichia coli phenotypes on the rate-yield plane. We found that the measured phenotypes distribute non-uniformly to form a highly stratified fitness landscape. Systems analysis of the ME-model simulations suggest that this stratification results from discrete ATP generation strategies. Accordingly, we define "aero-types", a phenotypic trait that characterizes how a balanced proteome can achieve a given growth rate by modulating 1) the relative utilization of oxidative phosphorylation, glycolysis, and fermentation pathways; and 2) the differential employment of electron-transport-chain enzymes. This global, quantitative, and mechanistic systems biology interpretation of fitness landscape formed upon proteome allocation offers a fundamental understanding of bacterial physiology and evolution dynamics.
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22
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Titrating bacterial growth and chemical biosynthesis for efficient N-acetylglucosamine and N-acetylneuraminic acid bioproduction. Nat Commun 2020; 11:5078. [PMID: 33033266 PMCID: PMC7544899 DOI: 10.1038/s41467-020-18960-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 09/21/2020] [Indexed: 12/27/2022] Open
Abstract
Metabolic engineering facilitates chemical biosynthesis by rewiring cellular resources to produce target compounds. However, an imbalance between cell growth and bioproduction often reduces production efficiency. Genetic code expansion (GCE)-based orthogonal translation systems incorporating non-canonical amino acids (ncAAs) into proteins by reassigning non-canonical codons to ncAAs qualify for balancing cellular metabolism. Here, GCE-based cell growth and biosynthesis balance engineering (GCE-CGBBE) is developed, which is based on titrating expression of cell growth and metabolic flux determinant genes by constructing ncAA-dependent expression patterns. We demonstrate GCE-CGBBE in genome-recoded Escherichia coli Δ321AM by precisely balancing glycolysis and N-acetylglucosamine production, resulting in a 4.54-fold increase in titer. GCE-CGBBE is further expanded to non-genome-recoded Bacillus subtilis to balance growth and N-acetylneuraminic acid bioproduction by titrating essential gene expression, yielding a 2.34-fold increase in titer. Moreover, the development of ncAA-dependent essential gene expression regulation shows efficient biocontainment of engineered B. subtilis to avoid unintended proliferation in nature. An imbalance between cell growth and bioproduction of engineered microbes often reduces production efficiency. Here, the authors report genetic code expansion-based cell growth and biosynthesis balance engineering to achieve high levels production of N-acetylglucosamine in E. coli and N-acetylneuraminic acid in B. subtilis.
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23
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Cosetta CM, Kfoury N, Robbat A, Wolfe BE. Fungal volatiles mediate cheese rind microbiome assembly. Environ Microbiol 2020; 22:4745-4760. [PMID: 32869420 DOI: 10.1111/1462-2920.15223] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 08/28/2020] [Accepted: 08/28/2020] [Indexed: 12/01/2022]
Abstract
In vitro studies in plant, soil, and human systems have shown that microbial volatiles can mediate microbe-microbe or microbe-host interactions. These previous studies have often used artificially high concentrations of volatiles compared to in situ systems and have not demonstrated the roles volatiles play in mediating community-level dynamics. We used the notoriously volatile cheese rind microbiome to identify bacteria responsive to volatiles produced by five widespread cheese fungi. Vibrio casei had the strongest growth stimulation when exposed to all fungi. In multispecies community experiments, fungal volatiles caused a shift to a Vibrio-dominated community, potentially explaining the widespread occurrence of Vibrio in surface-ripened cheeses. RNA sequencing identified activation of the glyoxylate shunt as a possible mechanism underlying volatile-mediated growth promotion and community assembly. Our study demonstrates how airborne chemicals could be used to control the composition of microbiomes and illustrates how volatiles may impact the development of cheese rinds.
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Affiliation(s)
- Casey M Cosetta
- Department of Biology, Tufts University, 200 Boston Ave, Medford, MA, 02155, USA
| | - Nicole Kfoury
- Department of Chemistry, Tufts University, 62 Talbot Ave., Medford, MA, 02155, USA
| | - Albert Robbat
- Department of Chemistry, Tufts University, 62 Talbot Ave., Medford, MA, 02155, USA
| | - Benjamin E Wolfe
- Department of Biology, Tufts University, 200 Boston Ave, Medford, MA, 02155, USA
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24
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Park MR, Chen Y, Thompson M, Benites VT, Fong B, Petzold CJ, Baidoo EEK, Gladden JM, Adams PD, Keasling JD, Simmons BA, Singer SW. Response of Pseudomonas putida to Complex, Aromatic-Rich Fractions from Biomass. CHEMSUSCHEM 2020; 13:4455-4467. [PMID: 32160408 DOI: 10.1002/cssc.202000268] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/11/2020] [Indexed: 06/10/2023]
Abstract
There is strong interest in the valorization of lignin to produce valuable products; however, its structural complexity has been a conversion bottleneck. Chemical pretreatment liberates lignin-derived soluble fractions that may be upgraded by bioconversion. Cholinium ionic liquid pretreatment of sorghum produced soluble, aromatic-rich fractions that were converted by Pseudomonas putida (P. putida), a promising host for aromatic bioconversion. Growth studies and mutational analysis demonstrated that P. putida growth on these fractions was dependent on aromatic monomers but unknown factors also contributed. Proteomic and metabolomic analyses indicated that these unknown factors were amino acids and residual ionic liquid; the oligomeric aromatic fraction derived from lignin was not converted. A cholinium catabolic pathway was identified, and the deletion of the pathway stopped the ability of P. putida to grow on cholinium ionic liquid. This work demonstrates that aromatic-rich fractions obtained through pretreatment contain multiple substrates; conversion strategies should account for this complexity.
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Affiliation(s)
- Mee-Rye Park
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Yan Chen
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Mitchell Thompson
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Veronica T Benites
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Bonnie Fong
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Christopher J Petzold
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Edward E K Baidoo
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - John M Gladden
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Biomass Science and Conversion Technology, Sandia National Laboratories, 7011 East Avenue, Livermore, CA, 94551, USA
| | - Paul D Adams
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Department of Bioengineering, University of California, Berkeley, CA, 94720, USA
| | - Jay D Keasling
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Department of Bioengineering, University of California, Berkeley, CA, 94720, USA
- Department of Chemical & Biomolecular Engineering, University of California, Berkeley, CA, 94720, USA
- Center for Biosustainability, Danish Technical University, Lyngby, Denmark
- Center for Synthetic Biochemistry, Institute for Synthetic Biology, Shenzhen Institutes for Advanced Technology, Shenzhen, China
| | - Blake A Simmons
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Steven W Singer
- Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
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Vasilakou E, van Loosdrecht MCM, Wahl SA. Escherichia coli metabolism under short-term repetitive substrate dynamics: adaptation and trade-offs. Microb Cell Fact 2020; 19:116. [PMID: 32471427 PMCID: PMC7260802 DOI: 10.1186/s12934-020-01379-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 05/25/2020] [Indexed: 12/04/2022] Open
Abstract
Background Microbial metabolism is highly dependent on the environmental conditions. Especially, the substrate concentration, as well as oxygen availability, determine the metabolic rates. In large-scale bioreactors, microorganisms encounter dynamic conditions in substrate and oxygen availability (mixing limitations), which influence their metabolism and subsequently their physiology. Earlier, single substrate pulse experiments were not able to explain the observed physiological changes generated under large-scale industrial fermentation conditions. Results In this study we applied a repetitive feast–famine regime in an aerobic Escherichia coli culture in a time-scale of seconds. The regime was applied for several generations, allowing cells to adapt to the (repetitive) dynamic environment. The observed response was highly reproducible over the cycles, indicating that cells were indeed fully adapted to the regime. We observed an increase of the specific substrate and oxygen consumption (average) rates during the feast–famine regime, compared to a steady-state (chemostat) reference environment. The increased rates at same (average) growth rate led to a reduced biomass yield (30% lower). Interestingly, this drop was not followed by increased by-product formation, pointing to the existence of energy-spilling reactions. During the feast–famine cycle, the cells rapidly increased their uptake rate. Within 10 s after the beginning of the feeding, the substrate uptake rate was higher (4.68 μmol/gCDW/s) than reported during batch growth (3.3 μmol/gCDW/s). The high uptake led to an accumulation of several intracellular metabolites, during the feast phase, accounting for up to 34% of the carbon supplied. Although the metabolite concentrations changed rapidly, the cellular energy charge remained unaffected, suggesting well-controlled balance between ATP producing and ATP consuming reactions. Conclusions The adaptation of the physiology and metabolism of E. coli under substrate dynamics, representative for large-scale fermenters, revealed the existence of several cellular mechanisms coping with stress. Changes in the substrate uptake system, storage potential and energy-spilling processes resulted to be of great importance. These metabolic strategies consist a meaningful step to further tackle reduced microbial performance, observed under large-scale cultivations.
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Affiliation(s)
- Eleni Vasilakou
- Department of Biotechnology, Delft University of Technology, Van der Maasweg, 2629 HZ, Delft, The Netherlands.
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, Van der Maasweg, 2629 HZ, Delft, The Netherlands
| | - S Aljoscha Wahl
- Department of Biotechnology, Delft University of Technology, Van der Maasweg, 2629 HZ, Delft, The Netherlands.
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García-Romero I, Nogales J, Díaz E, Santero E, Floriano B. Understanding the metabolism of the tetralin degrader Sphingopyxis granuli strain TFA through genome-scale metabolic modelling. Sci Rep 2020; 10:8651. [PMID: 32457330 PMCID: PMC7250832 DOI: 10.1038/s41598-020-65258-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 04/30/2020] [Indexed: 11/23/2022] Open
Abstract
Sphingopyxis granuli strain TFA is an α-proteobacterium that belongs to the sphingomonads, a group of bacteria well-known for its degradative capabilities and oligotrophic metabolism. Strain TFA is the only bacterium in which the mineralisation of the aromatic pollutant tetralin has been completely characterized at biochemical, genetic, and regulatory levels and the first Sphingopyxis characterised as facultative anaerobe. Here we report additional metabolic features of this α-proteobacterium using metabolic modelling and the functional integration of genomic and transcriptomic data. The genome-scale metabolic model (GEM) of strain TFA, which has been manually curated, includes information on 743 genes, 1114 metabolites and 1397 reactions. This represents the largest metabolic model for a member of the Sphingomonadales order thus far. The predictive potential of this model was validated against experimentally calculated growth rates on different carbon sources and under different growth conditions, including both aerobic and anaerobic metabolisms. Moreover, new carbon and nitrogen sources were predicted and experimentally validated. The constructed metabolic model was used as a platform for the incorporation of transcriptomic data, generating a more robust and accurate model. In silico flux analysis under different metabolic scenarios highlighted the key role of the glyoxylate cycle in the central metabolism of strain TFA.
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Affiliation(s)
- Inmaculada García-Romero
- Centro Andaluz de Biología del Desarrollo, CSIC-Universidad Pablo de Olavide, ES-41013, Seville, Spain
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, BT9 7BL, United Kingdom
| | - Juan Nogales
- Department of Systems Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), 28049, Madrid, Spain
- Interdisciplinary Platform for Sustainable Plastics towards a Circular Economy-Spanish National Research Council (SusPlast-CSIC), Madrid, Spain
| | - Eduardo Díaz
- Department of Microbial and Plant Biotechnology. Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas (CIB-CSIC), 28040, Madrid, Spain
| | - Eduardo Santero
- Centro Andaluz de Biología del Desarrollo, CSIC-Universidad Pablo de Olavide, ES-41013, Seville, Spain
| | - Belén Floriano
- Department of Molecular Biology and Biochemical Engineering. Universidad Pablo de Olavide, ES-41013, Seville, Spain.
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Integrated strain engineering and bioprocessing strategies for high-level bio-based production of 3-hydroxyvalerate in Escherichia coli. Appl Microbiol Biotechnol 2020; 104:5259-5272. [PMID: 32291486 DOI: 10.1007/s00253-020-10580-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 03/15/2020] [Accepted: 03/23/2020] [Indexed: 12/12/2022]
Abstract
As petro-based production generates numerous environmental impacts and their associated technological concerns, bio-based production has been well recognized these days as a modern alternative to manufacture chemical products in a more renewable, environmentally friendly, and sustainable manner. Herein, we report the development of a microbial bioprocess for high-level and potentially economical production of 3-hydroxyvalerate (3-HV), a valuable special chemical with multiple applications in chemical, biopolymer, and pharmaceutical industries, from glycerol, which can be cheaply and renewably refined as a byproduct from biodiesel production. We used our recently derived 3-HV-producing Escherichia coli strains for bioreactor characterization under various culture conditions. In the parental strain, 3-HV biosynthesis was limited by the intracellular availability of propionyl-CoA, whose formation was favored by anaerobic conditions, which often compromised cell growth. With appropriate strain engineering, we demonstrated that 3-HV can be effectively produced under both microaerobic (close to anaerobic) and aerobic conditions, which determine the direction of dissimilated carbon flux toward the succinate node in the tricarboxylic acid (TCA) cycle. We first used the ∆sdhA single mutant strain, in which the dissimilated carbon flux was primarily directed to the Sleeping beauty mutase (Sbm) pathway (via the reductive TCA branch, with enhanced cell growth under microaerobic conditions, achieving 3.08 g L-1 3-HV in a fed-batch culture. In addition, we used the ∆sdhA-∆iclR double mutant strain, in which the dissimilated carbon flux was directed from the TCA cycle to the Sbm pathway via the deregulated glyoxylate shunt, for cultivation under rather aerobic conditions. In addition to demonstrating effective cell growth, this strain has shown impressive 3-HV biosynthesis (up to 10.6 g L-1), equivalent to an overall yield of 18.8% based on consumed glycerol, in aerobic fed-batch culture. This study not only represents one of the most effective bio-based production of 3-HV from structurally unrelated carbons to date, but also highlights the importance of integrated strain engineering and bioprocessing strategies to enhance bio-based production.Key points• TCA cycle engineering was applied to enhance 3-HV biosynthesis in E. coli. • Effects of oxygenic conditions on 3-HV in E. coli biosynthesis were investigated. • Bioreactor characterization of 3-HV biosynthesis in E. coli was performed.
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Schütze A, Benndorf D, Püttker S, Kohrs F, Bettenbrock K. The Impact of ackA, pta, and ackA-pta Mutations on Growth, Gene Expression and Protein Acetylation in Escherichia coli K-12. Front Microbiol 2020; 11:233. [PMID: 32153530 PMCID: PMC7047895 DOI: 10.3389/fmicb.2020.00233] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 01/31/2020] [Indexed: 01/06/2023] Open
Abstract
Acetate is a characteristic by-product of Escherichia coli K-12 growing in batch cultures with glucose, both under aerobic as well as anaerobic conditions. While the reason underlying aerobic acetate production is still under discussion, during anaerobic growth acetate production is important for ATP generation by substrate level phosphorylation. Under both conditions, acetate is produced by a pathway consisting of the enzyme phosphate acetyltransferase (Pta) producing acetyl-phosphate from acetyl-coenzyme A, and of the enzyme acetate kinase (AckA) producing acetate from acetyl-phosphate, a reaction that is coupled to the production of ATP. Mutants in the AckA-Pta pathway differ from each other in the potential to produce and accumulate acetyl-phosphate. In the publication at hand, we investigated different mutants in the acetate pathway, both under aerobic as well as anaerobic conditions. While under aerobic conditions only small changes in growth rate were observed, all acetate mutants showed severe reduction in growth rate and changes in the by-product pattern during anaerobic growth. The AckA- mutant showed the most severe growth defect. The glucose uptake rate and the ATP concentration were strongly reduced in this strain. This mutant exhibited also changes in gene expression. In this strain, the atoDAEB operon was significantly upregulated under anaerobic conditions hinting to the production of acetoacetate. During anaerobic growth, protein acetylation increased significantly in the ackA mutant. Acetylation of several enzymes of glycolysis and central metabolism, of aspartate carbamoyl transferase, methionine synthase, catalase and of proteins involved in translation was increased. Supplementation of methionine and uracil eliminated the additional growth defect of the ackA mutant. The data show that anaerobic, fermentative growth of mutants in the AckA-Pta pathway is reduced but still possible. Growth reduction can be explained by the lack of an important ATP generating pathway of mixed acid fermentation. An ackA deletion mutant is more severely impaired than pta or ackA-pta deletion mutants. This is most probably due to the production of acetyl-P in the ackA mutant, leading to increased protein acetylation.
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Affiliation(s)
- Andrea Schütze
- Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Dirk Benndorf
- Bioprocess Engineering, Otto von Guericke University, Magdeburg, Germany
| | - Sebastian Püttker
- Bioprocess Engineering, Otto von Guericke University, Magdeburg, Germany
| | - Fabian Kohrs
- Bioprocess Engineering, Otto von Guericke University, Magdeburg, Germany
| | - Katja Bettenbrock
- Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
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Miscevic D, Mao JY, Moo-Young M, Chou CHP. High-level heterologous production of propionate in engineered Escherichia coli. Biotechnol Bioeng 2020; 117:1304-1315. [PMID: 31956980 DOI: 10.1002/bit.27276] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Revised: 01/13/2020] [Accepted: 01/16/2020] [Indexed: 12/14/2022]
Abstract
A propanologenic (i.e., 1-propanol-producing) bacterium Escherichia coli strain was previously derived by activating the genomic sleeping beauty mutase (Sbm) operon. The activated Sbm pathway branches out of the tricarboxylic acid (TCA) cycle at the succinyl-CoA node to form propionyl-CoA and its derived metabolites of 1-propanol and propionate. In this study, we targeted several TCA cycle genes encoding enzymes near the succinyl-CoA node for genetic manipulation to identify the individual contribution of the carbon flux into the Sbm pathway from the three TCA metabolic routes, that is, oxidative TCA cycle, reductive TCA branch, and glyoxylate shunt. For the control strain CPC-Sbm, in which propionate biosynthesis occurred under relatively anaerobic conditions, the carbon flux into the Sbm pathway was primarily derived from the reductive TCA branch, and both succinate availability and the SucCD-mediated interconversion of succinate/succinyl-CoA were critical for such carbon flux redirection. Although the oxidative TCA cycle normally had a minimal contribution to the carbon flux redirection, the glyoxylate shunt could be an alternative and effective carbon flux contributor under aerobic conditions. With mechanistic understanding of such carbon flux redirection, metabolic strategies based on blocking the oxidative TCA cycle (via ∆sdhA mutation) and deregulating the glyoxylate shunt (via ∆iclR mutation) were developed to enhance the carbon flux redirection and therefore propionate biosynthesis, achieving a high propionate titer of 30.9 g/L with an overall propionate yield of 49.7% upon fed-batch cultivation of the double mutant strain CPC-Sbm∆sdhA∆iclR under aerobic conditions. The results also suggest that the Sbm pathway could be metabolically active under both aerobic and anaerobic conditions.
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Affiliation(s)
- Dragan Miscevic
- Department of Chemical Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Ju-Yi Mao
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, Taiwan
| | - Murray Moo-Young
- Department of Chemical Engineering, University of Waterloo, Waterloo, Ontario, Canada
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Wada K, Koike H, Fujii T, Morita T. Targeted transcriptomic study of the implication of central metabolic pathways in mannosylerythritol lipids biosynthesis in Pseudozyma antarctica T-34. PLoS One 2020; 15:e0227295. [PMID: 31923270 PMCID: PMC6953796 DOI: 10.1371/journal.pone.0227295] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 12/16/2019] [Indexed: 11/19/2022] Open
Abstract
Pseudozyma antarctica is a nonpathogenic phyllosphere yeast known as an excellent producer of industrial lipases and mannosylerythritol lipids (MELs), which are multi-functional glycolipids. The fungus produces a much higher amount of MELs from vegetable oil than from glucose, whereas its close relative, Ustilago maydis UM521, produces a lower amount of MELs from vegetable oil. In the present study, we used previous gene expression profiles measured by DNA microarray analyses after culturing on two carbon sources, glucose and soybean oil, to further characterize MEL biosynthesis in P. antarctica T-34. A total of 264 genes were found with induction ratios and expression intensities under oily conditions with similar tendencies to those of MEL cluster genes. Of these, 93 were categorized as metabolic genes using the Eukaryotic Orthologous Groups classification. Within this metabolic category, amino acids, carbohydrates, inorganic ions, and secondary metabolite metabolism, as well as energy production and conversion, but not lipid metabolism, were enriched. Furthermore, genes involved in central metabolic pathways, such as glycolysis and the tricarboxylic acid cycle, were highly induced in P. antarctica T-34 under oily conditions, whereas they were suppressed in U. maydis UM521. These results suggest that the central metabolism of P. antarctica T-34 under oily conditions contributes to its excellent oil utilization and extracellular glycolipid production.
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Affiliation(s)
- Keisuke Wada
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Kagamiyama, Higashi-Hiroshima, Hiroshima, Japan
| | - Hideaki Koike
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Higashi, Tsukuba, Ibaraki, Japan
| | - Tatsuya Fujii
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Kagamiyama, Higashi-Hiroshima, Hiroshima, Japan
| | - Tomotake Morita
- Research Institute for Innovation in Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Higashi, Tsukuba, Ibaraki, Japan
- * E-mail:
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32
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Gallego-Jara J, Terol GL, Écija Conesa A, Zambelli B, Cánovas Díaz M, de Diego Puente T. Characterization of acetyl-CoA synthetase kinetics and ATP-binding. Biochim Biophys Acta Gen Subj 2019; 1863:1040-1049. [PMID: 30928490 DOI: 10.1016/j.bbagen.2019.03.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 03/20/2019] [Accepted: 03/25/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND The superfamily of adenylating enzymes is a large family of enzymes broadly distributed from bacteria to humans. Acetyl-CoA synthetase (Acs), member of this family, is a metabolic enzyme with an essential role in Escherichia coli (E. coli) acetate metabolism, whose catalytic activity is regulated by acetylation/deacetylation in vivo. METHODS In this study, the kinetics and thermodynamic parameters of deacetylated and acetylated E. coli Acs were studied for the adenylating step. Moreover, the role of the T264, K270, D500 and K609 residues in catalysis and ATP-binding was also determined by Isothermal titration calorimetry. RESULTS The results showed that native Acs enzyme binds ATP in an endothermic way. The dissociation constant has been determined and ATP-binding showed no significant differences between acetylated and deacetylated enzyme, although kcat was much higher for the deacetylated enzyme. However, K609 lysine mutation resulted in an increase in ATP-Acs-affinity and in a total loss of enzymatic activity, while T264 and D500 mutant proteins showed a total loss of ATP-binding ability and a decrease in catalytic activity. K609 site-specified acetylation induced a change in Acs conformation which resulted in an exothermic and more energetic ATP-binding. CONCLUSIONS The differences in ATP-binding could explain the broadly conserved inactivation of Acs when K609 is acetylated. GENERAL SIGNIFICANCE The results presented in this study demonstrate the importance of the selected residues in Acs ATP-binding and represent an advance in our understanding of the adenylation step of the superfamily of adenylating enzymes and of their acetylation/deacetylation regulation.
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Affiliation(s)
- Julia Gallego-Jara
- Department of Biochemistry and Molecular Biology and Immunology (B), Faculty of Chemistry, University of Murcia, Campus of Espinardo, Regional Campus of International Excellence "Campus Mare Nostrum", P.O. Box 4021, Murcia E-30100, Spain.
| | - Gema Lozano Terol
- Department of Biochemistry and Molecular Biology and Immunology (B), Faculty of Chemistry, University of Murcia, Campus of Espinardo, Regional Campus of International Excellence "Campus Mare Nostrum", P.O. Box 4021, Murcia E-30100, Spain.
| | - Ana Écija Conesa
- Department of Biochemistry and Molecular Biology and Immunology (B), Faculty of Chemistry, University of Murcia, Campus of Espinardo, Regional Campus of International Excellence "Campus Mare Nostrum", P.O. Box 4021, Murcia E-30100, Spain
| | - Barbara Zambelli
- Laboratory of Bioinorganic Chemistry, University of Bologna, Department of Pharmacy and Biotechnology, Via Giuseppe Fanin 40, I-40127 Bologna, Italy
| | - Manuel Cánovas Díaz
- Department of Biochemistry and Molecular Biology and Immunology (B), Faculty of Chemistry, University of Murcia, Campus of Espinardo, Regional Campus of International Excellence "Campus Mare Nostrum", P.O. Box 4021, Murcia E-30100, Spain
| | - Teresa de Diego Puente
- Department of Biochemistry and Molecular Biology and Immunology (B), Faculty of Chemistry, University of Murcia, Campus of Espinardo, Regional Campus of International Excellence "Campus Mare Nostrum", P.O. Box 4021, Murcia E-30100, Spain
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Hart SFM, Mi H, Green R, Xie L, Pineda JMB, Momeni B, Shou W. Uncovering and resolving challenges of quantitative modeling in a simplified community of interacting cells. PLoS Biol 2019; 17:e3000135. [PMID: 30794534 PMCID: PMC6402699 DOI: 10.1371/journal.pbio.3000135] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 03/06/2019] [Accepted: 01/18/2019] [Indexed: 12/22/2022] Open
Abstract
Quantitative modeling is useful for predicting behaviors of a system and for rationally constructing or modifying the system. The predictive power of a model relies on accurate quantification of model parameters. Here, we illustrate challenges in parameter quantification and offer means to overcome these challenges, using a case example in which we quantitatively predict the growth rate of a cooperative community. Specifically, the community consists of two Saccharomyces cerevisiae strains, each engineered to release a metabolite required and consumed by its partner. The initial model, employing parameters measured in batch monocultures with zero or excess metabolite, failed to quantitatively predict experimental results. To resolve the model-experiment discrepancy, we chemically identified the correct exchanged metabolites, but this did not improve model performance. We then remeasured strain phenotypes in chemostats mimicking the metabolite-limited community environments, while mitigating or incorporating effects of rapid evolution. Almost all phenotypes we measured, including death rate, metabolite release rate, and the amount of metabolite consumed per cell birth, varied significantly with the metabolite environment. Once we used parameters measured in a range of community-like chemostat environments, prediction quantitatively agreed with experimental results. In summary, using a simplified community, we uncovered and devised means to resolve modeling challenges that are likely general to living systems.
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Affiliation(s)
- Samuel F. M. Hart
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Hanbing Mi
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Robin Green
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Li Xie
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Jose Mario Bello Pineda
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Babak Momeni
- Department of Biology, Boston College, Boston, Massachusetts, United States of America
| | - Wenying Shou
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
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Liu H, Song R, Liang Y, Zhang T, Deng L, Wang F, Tan T. Genetic manipulation of Escherichia coli central carbon metabolism for efficient production of fumaric acid. BIORESOURCE TECHNOLOGY 2018; 270:96-102. [PMID: 30212779 DOI: 10.1016/j.biortech.2018.08.024] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 08/06/2018] [Accepted: 08/07/2018] [Indexed: 05/06/2023]
Abstract
Fumaric acid is one of the top 12-biomass building-block chemicals. In this study, we reported manipulation of E. coli central carbon metabolism with the aim to decrease the by-products and improve fumaric acid production. PEP-dependent glucose phosphotransferase system was replaced with a galactose translocation system to minimize the consumption of phosphoenolpyruvate. Engineering anaplerotic pathway (phosphoenolpyruvate carboxylase) was employed to redistribute carbon flux from glycolysis to Krebs cycle. Deletion of malate dehydrogenase and overexpression of acetyl-CoA synthase could decrease the byproducts malic acid and acetic acid. The combined strategies led to fumaric acid yield up to 1.53 g/g dry cell weight, a 50% increase compared with the parental strain. The result demonstrated that these genetic modifications were effective strategies for improving the production of fumaric acid and the engineered strain may serve a platform microbial cell factory for efficient production of fumaric acid or other dicarboxylic acids.
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Affiliation(s)
- Huan Liu
- Beijing Bioprocess Key Laboratory, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Ruirui Song
- Institute of Food and Agriculture Standardization, China National Institute of Standardization, Beijing 100191, PR China
| | - Yue Liang
- Beijing Bioprocess Key Laboratory, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Ting Zhang
- Comprehensive Liver Cancer Center, the 302 Hospital of PLA, Beijing 100039, PR China
| | - Li Deng
- Beijing Bioprocess Key Laboratory, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China.
| | - Fang Wang
- Beijing Bioprocess Key Laboratory, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Tianwei Tan
- Beijing Bioprocess Key Laboratory, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
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Novak K, Flöckner L, Erian AM, Freitag P, Herwig C, Pflügl S. Characterizing the effect of expression of an acetyl-CoA synthetase insensitive to acetylation on co-utilization of glucose and acetate in batch and continuous cultures of E. coli W. Microb Cell Fact 2018; 17:109. [PMID: 29986728 PMCID: PMC6036698 DOI: 10.1186/s12934-018-0955-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 07/02/2018] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Due to its high stress tolerance and low acetate secretion, Escherichia coli W is reported to be a good production host for several metabolites and recombinant proteins. However, simultaneous co-utilization of glucose and other substrates such as acetate remains a challenge. The activity of acetyl-CoA-synthetase, one of the key enzymes involved in acetate assimilation is tightly regulated on a transcriptional and post-translational level. The aim of this study was to engineer E. coli W for overexpression of an acetylation insensitive acetyl-CoA-synthetase and to characterize this strain in batch and continuous cultures using glucose, acetate and during co-utilization of both substrates. RESULTS Escherichia coli W engineered to overexpress an acetylation-insensitive acetyl-CoA synthetase showed a 2.7-fold increase in acetate uptake in a batch process containing glucose and high concentrations of acetate compared to a control strain, indicating more efficient co-consumption of glucose and acetate. When acetate was used as the carbon source, batch duration could significantly be decreased in the overexpression strain, possibly due to alleviation of acetate toxicity. Chemostat cultivations with different dilution rates using glucose revealed only minor differences between the overexpression and control strain. Accelerostat cultivations using dilution rates between 0.20 and 0.70 h-1 indicated that E. coli W is naturally capable of efficiently co-utilizing glucose and acetate over a broad range of specific growth rates. Expression of acetyl-CoA synthetase resulted in acetate and glucose accumulation at lower dilution rates compared to the control strain. This observation can possibly be attributed to a higher ratio between acs and pta-ackA in the overexpression strain as revealed by gene expression analysis. This would result in enhanced energy dissipation caused by an imbalance in the Pta-AckA-Acs cycle. Furthermore, yjcH and actP, genes co-transcribed with acetyl-CoA synthetase showed significant down-regulation at elevated dilution rates. CONCLUSIONS Escherichia coli W expressing an acetylation-insensitive acetyl-CoA synthetase was shown to be a promising candidate for mixed feed processes using glucose and acetate. Comparison between batch and continuous cultures revealed distinct differences in glucose-acetate co-utilization behavior, requiring additional investigations such as multi-omics analysis and further engineering towards even more efficient co-utilization strains of E. coli W.
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Affiliation(s)
- Katharina Novak
- Research Area Biochemical Engineering, Institute for Chemical, Environmental and Bioscience Engineering, Technische Universität Wien, Gumpendorfer Straße 1a, 1060 Vienna, Austria
| | - Lukas Flöckner
- Research Area Biochemical Engineering, Institute for Chemical, Environmental and Bioscience Engineering, Technische Universität Wien, Gumpendorfer Straße 1a, 1060 Vienna, Austria
| | - Anna Maria Erian
- Research Area Biochemical Engineering, Institute for Chemical, Environmental and Bioscience Engineering, Technische Universität Wien, Gumpendorfer Straße 1a, 1060 Vienna, Austria
| | - Philipp Freitag
- Research Area Biochemical Engineering, Institute for Chemical, Environmental and Bioscience Engineering, Technische Universität Wien, Gumpendorfer Straße 1a, 1060 Vienna, Austria
| | - Christoph Herwig
- Research Area Biochemical Engineering, Institute for Chemical, Environmental and Bioscience Engineering, Technische Universität Wien, Gumpendorfer Straße 1a, 1060 Vienna, Austria
- Christian Doppler Laboratory for Mechanistic and Physiological Methods for Improved Bioprocesses, Gumpendorfer Straße 1a, 1060 Vienna, Austria
| | - Stefan Pflügl
- Research Area Biochemical Engineering, Institute for Chemical, Environmental and Bioscience Engineering, Technische Universität Wien, Gumpendorfer Straße 1a, 1060 Vienna, Austria
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Gallego-Jara J, Écija Conesa A, de Diego Puente T, Lozano Terol G, Cánovas Díaz M. Characterization of CobB kinetics and inhibition by nicotinamide. PLoS One 2017; 12:e0189689. [PMID: 29253849 PMCID: PMC5734772 DOI: 10.1371/journal.pone.0189689] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 11/30/2017] [Indexed: 12/31/2022] Open
Abstract
Lysine acetylation has emerged as a global protein regulation system in all domains of life. Sirtuins, or Sir2-like enzymes, are a family of histone deacetylases characterized by their employing NAD+ as a co-substrate. Sirtuins can deacetylate several acetylated proteins, but a consensus substrate recognition sequence has not yet been established. Product inhibition of many eukaryotic sirtuins by nicotinamide and its analogues has been studied in vitro due to their potential role as anticancer agents. In this work, the kinetics of CobB, the main Escherichia coli deacetylase, have been characterized. To our knowledge, this is the first kinetic characterization of a sirtuin employing a fully acetylated and natively folded protein as a substrate. CobB deacetylated several acetyl-CoA synthetase acetylated lysines with a single kinetic rate. In addition, in vitro nicotinamide inhibition of CobB has been characterized, and the intracellular nicotinamide concentrations have been determined under different growth conditions. The results suggest that nicotinamide can act as a CobB regulator in vivo. A nicotinamidase deletion strain was thus phenotypically characterized, and it behaved similarly to the ΔcobB strain. The results of this work demonstrate the potential regulatory role of the nicotinamide metabolite in vivo.
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Affiliation(s)
- Julia Gallego-Jara
- Department of Biochemistry and Molecular Biology and Immunology (B), Faculty of Chemistry, University of Murcia, Campus of Espinardo, Regional Campus of International Excellence ‘‘Campus Mare Nostrum”, Murcia, Spain
- * E-mail:
| | - Ana Écija Conesa
- Department of Biochemistry and Molecular Biology and Immunology (B), Faculty of Chemistry, University of Murcia, Campus of Espinardo, Regional Campus of International Excellence ‘‘Campus Mare Nostrum”, Murcia, Spain
| | - Teresa de Diego Puente
- Department of Biochemistry and Molecular Biology and Immunology (B), Faculty of Chemistry, University of Murcia, Campus of Espinardo, Regional Campus of International Excellence ‘‘Campus Mare Nostrum”, Murcia, Spain
| | - Gema Lozano Terol
- Department of Biochemistry and Molecular Biology and Immunology (B), Faculty of Chemistry, University of Murcia, Campus of Espinardo, Regional Campus of International Excellence ‘‘Campus Mare Nostrum”, Murcia, Spain
| | - Manuel Cánovas Díaz
- Department of Biochemistry and Molecular Biology and Immunology (B), Faculty of Chemistry, University of Murcia, Campus of Espinardo, Regional Campus of International Excellence ‘‘Campus Mare Nostrum”, Murcia, Spain
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Anane E, López C DC, Neubauer P, Cruz Bournazou MN. Modelling overflow metabolism in Escherichia coli by acetate cycling. Biochem Eng J 2017. [DOI: 10.1016/j.bej.2017.05.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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38
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Why Do Fast-Growing Bacteria Enter Overflow Metabolism? Testing the Membrane Real Estate Hypothesis. Cell Syst 2017; 5:95-104. [PMID: 28755958 DOI: 10.1016/j.cels.2017.06.005] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 04/13/2017] [Accepted: 06/09/2017] [Indexed: 11/22/2022]
Abstract
Bacteria and other cells show a puzzling behavior. At high growth rates, E. coli switch from respiration (which is ATP-efficient) to using fermentation for additional ATP (which is inefficient). This overflow metabolism results in a several-fold decrease in ATP produced per glucose molecule provided as food. By integrating diverse types of experimental data into a simple biophysical model, we give evidence that this onset is the result of the membrane real estate hypothesis: Fast growth drives cells to be bigger, reducing their surface-to-volume ratios. This decreases the membrane area available for respiratory proteins despite growing demand, causing increased crowding. Only when respiratory proteins reach their crowding limit does the cell activate fermentation, since fermentation allows faster ATP production per unit membrane area. Surface limitation thus creates a Pareto trade-off between membrane efficiency and ATP yield that links metabolic choice to the size and shape of a bacterial cell. By exploring the predictions that emerge from this trade-off, we show how consideration of molecular structures, energetics, rates, and equilibria can provide important insight into cellular behavior.
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Enjalbert B, Millard P, Dinclaux M, Portais JC, Létisse F. Acetate fluxes in Escherichia coli are determined by the thermodynamic control of the Pta-AckA pathway. Sci Rep 2017; 7:42135. [PMID: 28186174 PMCID: PMC5301487 DOI: 10.1038/srep42135] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 12/28/2016] [Indexed: 12/30/2022] Open
Abstract
Escherichia coli excretes acetate upon growth on fermentable sugars, but the regulation of this production remains elusive. Acetate excretion on excess glucose is thought to be an irreversible process. However, dynamic 13C-metabolic flux analysis revealed a strong bidirectional exchange of acetate between E. coli and its environment. The Pta-AckA pathway was found to be central for both flux directions, while alternative routes (Acs or PoxB) play virtually no role in glucose consumption. Kinetic modelling of the Pta-AckA pathway predicted that its flux is thermodynamically controlled by the extracellular acetate concentration in vivo. Experimental validations confirmed that acetate production can be reduced and even reversed depending solely on its extracellular concentration. Consistently, the Pta-AckA pathway can rapidly switch from acetate production to consumption. Contrary to current knowledge, E. coli is thus able to co-consume glucose and acetate under glucose excess. These metabolic capabilities were confirmed on other glycolytic substrates which support the growth of E. coli in the gut. These findings highlight the dual role of the Pta-AckA pathway in acetate production and consumption during growth on glycolytic substrates, uncover a novel regulatory mechanism that controls its flux in vivo, and significantly expand the metabolic capabilities of E. coli.
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Affiliation(s)
- Brice Enjalbert
- LISBP, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Pierre Millard
- LISBP, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Mickael Dinclaux
- LISBP, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | | | - Fabien Létisse
- LISBP, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
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40
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Bernal V, Castaño-Cerezo S, Cánovas M. Acetate metabolism regulation in Escherichia coli: carbon overflow, pathogenicity, and beyond. Appl Microbiol Biotechnol 2016; 100:8985-9001. [DOI: 10.1007/s00253-016-7832-x] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 08/22/2016] [Accepted: 08/24/2016] [Indexed: 12/11/2022]
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41
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Ahn S, Jung J, Jang IA, Madsen EL, Park W. Role of Glyoxylate Shunt in Oxidative Stress Response. J Biol Chem 2016; 291:11928-38. [PMID: 27036942 DOI: 10.1074/jbc.m115.708149] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Indexed: 12/16/2022] Open
Abstract
The glyoxylate shunt (GS) is a two-step metabolic pathway (isocitrate lyase, aceA; and malate synthase, glcB) that serves as an alternative to the tricarboxylic acid cycle. The GS bypasses the carbon dioxide-producing steps of the tricarboxylic acid cycle and is essential for acetate and fatty acid metabolism in bacteria. GS can be up-regulated under conditions of oxidative stress, antibiotic stress, and host infection, which implies that it plays important but poorly explored roles in stress defense and pathogenesis. In many bacterial species, including Pseudomonas aeruginosa, aceA and glcB are not in an operon, unlike in Escherichia coli In P. aeruginosa, we explored relationships between GS genes and growth, transcription profiles, and biofilm formation. Contrary to our expectations, deletion of aceA in P. aeruginosa improved cell growth under conditions of oxidative and antibiotic stress. Transcriptome data suggested that aceA mutants underwent a metabolic shift toward aerobic denitrification; this was supported by additional evidence, including up-regulation of denitrification-related genes, decreased oxygen consumption without lowering ATP yield, increased production of denitrification intermediates (NO and N2O), and increased cyanide resistance. The aceA mutants also produced a thicker exopolysaccharide layer; that is, a phenotype consistent with aerobic denitrification. A bioinformatic survey across known bacterial genomes showed that only microorganisms capable of aerobic metabolism possess the glyoxylate shunt. This trend is consistent with the hypothesis that the GS plays a previously unrecognized role in allowing bacteria to tolerate oxidative stress.
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Affiliation(s)
- Sungeun Ahn
- From the Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea and
| | - Jaejoon Jung
- From the Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea and
| | - In-Ae Jang
- From the Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea and
| | - Eugene L Madsen
- the Department of Microbiology, Cornell University, Ithaca, New York 14853
| | - Woojun Park
- From the Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea and
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42
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Basan M, Hui S, Okano H, Zhang Z, Shen Y, Williamson JR, Hwa T. Overflow metabolism in Escherichia coli results from efficient proteome allocation. Nature 2016; 528:99-104. [PMID: 26632588 PMCID: PMC4843128 DOI: 10.1038/nature15765] [Citation(s) in RCA: 425] [Impact Index Per Article: 53.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 10/01/2015] [Indexed: 12/27/2022]
Abstract
Overflow metabolism refers to the seemingly wasteful strategy in which cells use fermentation instead of the more efficient respiration to generate energy, despite the availability of oxygen. Known as Warburg effect in the context of cancer growth, this phenomenon occurs ubiquitously for fast growing cells, including bacteria, fungi, and mammalian cells, but its origin has remained mysterious despite decades of research. Here we study metabolic overflow in E. coli and show that it is a global physiological response used to cope with changing proteomic demands of energy biogenesis and biomass synthesis under different growth conditions. A simple model of proteomic resource allocation can quantitatively account for all of the observed behaviors and accurately predict responses to novel perturbations. The key hypothesis of the model, that the proteome cost of energy biogenesis by respiration exceeds that by fermentation, is quantitatively confirmed by direct measurement of protein abundances via quantitative mass spectrometry.
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Affiliation(s)
- Markus Basan
- Department of Physics, University at San Diego, La Jolla, of California California 92093-0374, USA.,Institute of Molecular Systems Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - Sheng Hui
- Department of Physics, University at San Diego, La Jolla, of California California 92093-0374, USA
| | - Hiroyuki Okano
- Department of Physics, University at San Diego, La Jolla, of California California 92093-0374, USA.,Section of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, California 92093 USA
| | - Zhongge Zhang
- Section of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, California 92093 USA
| | - Yang Shen
- Section of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, California 92093 USA
| | - James R Williamson
- Department of Integrative Structural and Computational Biology, Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Terence Hwa
- Department of Physics, University at San Diego, La Jolla, of California California 92093-0374, USA.,Section of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, California 92093 USA.,Institute for Theoretical Studies, ETH Zürich, 8092 Zürich, Switzerland
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43
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Peebo K, Valgepea K, Maser A, Nahku R, Adamberg K, Vilu R. Proteome reallocation in Escherichia coli with increasing specific growth rate. MOLECULAR BIOSYSTEMS 2015; 11:1184-93. [PMID: 25712329 DOI: 10.1039/c4mb00721b] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cells usually respond to changing growth conditions with a change in the specific growth rate (μ) and adjustment of their proteome to adapt and maintain metabolic efficiency. Description of the principles behind proteome resource allocation is important for understanding metabolic regulation in response to changing μ. Thus, we analysed the proteome resource allocation dynamics of Escherichia coli into different metabolic processes in response to changing μ. E. coli was grown on minimal and defined rich media in steady state continuous cultures at different μ and characterised combining two LC-MS/MS-based proteomics methods: stable isotope labelling by amino acids in cell culture (SILAC) and intensity based label-free absolute quantification. We detected slowly growing cells investing more proteome resources in energy generation and carbohydrate transport and metabolism whereas for achieving faster growth cells needed to devote most resources to translation and processes closely related to the protein synthesis pipeline. Furthermore, down-regulation of energy generation and carbohydrate metabolism proteins with faster growth displayed very similar expression dynamics with the global transcriptional regulator CRP (cyclic AMP receptor protein), pointing to a dominant protein resource allocating role of this protein. Our data also suggest that acetate overflow may be the result of global proteome resource optimisation as cells saved proteome resources by switching from fully respiratory to respiro-fermentative growth. The presented results give a quantitative overview of how E. coli adjusts its proteome to achieve faster growth and in future could contribute to the design of more efficient cell factories through proteome optimisation.
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Affiliation(s)
- Karl Peebo
- Tallinn University of Technology, Department of Chemistry, Akadeemia tee 15, 12618 Tallinn, Estonia
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44
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Franchini AG, Ihssen J, Egli T. Effect of Global Regulators RpoS and Cyclic-AMP/CRP on the Catabolome and Transcriptome of Escherichia coli K12 during Carbon- and Energy-Limited Growth. PLoS One 2015. [PMID: 26204448 PMCID: PMC4512719 DOI: 10.1371/journal.pone.0133793] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
For heterotrophic microbes, limited availability of carbon and energy sources is one of the major nutritional factors restricting the rate of growth in most ecosystems. Physiological adaptation to this hunger state requires metabolic versatility which usually involves expression of a wide range of different catabolic pathways and of high-affinity carbon transporters; together, this allows for simultaneous utilization of mixtures of carbonaceous compounds at low concentrations. In Escherichia coli the stationary phase sigma factor RpoS and the signal molecule cAMP are the major players in the regulation of transcription under such conditions; however, their interaction is still not fully understood. Therefore, during growth of E. coli in carbon-limited chemostat culture at different dilution rates, the transcriptomes, expression of periplasmic proteins and catabolomes of strains lacking one of these global regulators, either rpoS or adenylate cyclase (cya), were compared to those of the wild-type strain. The inability to synthesize cAMP exerted a strong negative influence on the expression of alternative carbon source uptake and degradation systems. In contrast, absence of RpoS increased the transcription of genes belonging to high-affinity uptake systems and central metabolism, presumably due to reduced competition of σD with σS. Phenotypical analysis confirmed this observation: The ability to respire alternative carbon substrates and to express periplasmic high-affinity binding proteins was eliminated in cya and crp mutants, while these properties were not affected in the rpoS mutant. As expected, transcription of numerous stress defence genes was negatively affected by the rpoS knock-out mutation. Interestingly, several genes of the RpoS stress response regulon were also down-regulated in the cAMP-negative strain indicating a coordinated global regulation. The results demonstrate that cAMP is crucial for catabolic flexibility during slow, carbon-limited growth, whereas RpoS is primarily involved in the regulation of stress response systems necessary for the survival of this bacterium under hunger conditions.
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Affiliation(s)
- Alessandro G. Franchini
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich, Switzerland
- * E-mail:
| | - Julian Ihssen
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich, Switzerland
| | - Thomas Egli
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich, Switzerland
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45
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Sargo CR, Campani G, Silva GG, Giordano RC, Da Silva AJ, Zangirolami TC, Correia DM, Ferreira EC, Rocha I. Salmonella typhimurium and Escherichia coli dissimilarity: Closely related bacteria with distinct metabolic profiles. Biotechnol Prog 2015; 31:1217-25. [PMID: 26097206 DOI: 10.1002/btpr.2128] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 05/20/2015] [Indexed: 01/17/2023]
Abstract
Live attenuated strains of Salmonella typhimurium have been extensively investigated as vaccines for a number of infectious diseases. However, there is still little information available concerning aspects of their metabolism. S. typhimurium and Escherichia coli show a high degree of similarity in terms of their genome contents and metabolic networks. However, this work presents experimental evidence showing that significant differences exist in their abilities to direct carbon fluxes to biomass and energy production. It is important to study the metabolism of Salmonella to elucidate the formation of acetate and other metabolites involved in optimizing the production of biomass, essential for the development of recombinant vaccines. The metabolism of Salmonella under aerobic conditions was assessed using continuous cultures performed at dilution rates ranging from 0.1 to 0.67 h(-1), with glucose as main substrate. Acetate assimilation and glucose metabolism under anaerobic conditions were also investigated using batch cultures. Chemostat cultivations showed deviation of carbon towards acetate formation, starting at dilution rates above 0.1 h(-1). This differed from previous findings for E. coli, where acetate accumulation was only detected at dilution rates exceeding 0.4 h(-1), and was due to the lower rate of acetate assimilation by S. typhimurium under aerobic conditions. Under anaerobic conditions, both microorganisms mainly produced ethanol, acetate, and formate. A genome-scale metabolic model, reconstructed for Salmonella based on an E. coli model, provided a poor description of the mixed fermentation pattern observed during Salmonella cultures, reinforcing the different patterns of carbon utilization exhibited by these closely related bacteria.
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Affiliation(s)
- Cintia R Sargo
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Gilson Campani
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Gabriel G Silva
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Roberto C Giordano
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Adilson J Da Silva
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Teresa C Zangirolami
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil
| | - Daniela M Correia
- Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905,, Brazil.,CEB-Centre of Biological Engineering, University of Minho, Campus De Gualtar, Braga, 4710-057,, Portugal
| | - Eugénio C Ferreira
- CEB-Centre of Biological Engineering, University of Minho, Campus De Gualtar, Braga, 4710-057,, Portugal
| | - Isabel Rocha
- CEB-Centre of Biological Engineering, University of Minho, Campus De Gualtar, Braga, 4710-057,, Portugal
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46
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Castaño-Cerezo S, Bernal V, Röhrig T, Termeer S, Cánovas M. Regulation of acetate metabolism in Escherichia coli BL21 by protein Nε-lysine acetylation. Appl Microbiol Biotechnol 2014; 99:3533-45. [DOI: 10.1007/s00253-014-6280-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 11/16/2014] [Accepted: 11/29/2014] [Indexed: 11/29/2022]
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47
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Bernal V, Castaño-Cerezo S, Gallego-Jara J, Écija-Conesa A, de Diego T, Iborra JL, Cánovas M. Regulation of bacterial physiology by lysine acetylation of proteins. N Biotechnol 2014; 31:586-95. [DOI: 10.1016/j.nbt.2014.03.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 02/28/2014] [Accepted: 03/02/2014] [Indexed: 01/10/2023]
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48
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Castaño-Cerezo S, Bernal V, Post H, Fuhrer T, Cappadona S, Sánchez-Díaz NC, Sauer U, Heck AJR, Altelaar AFM, Cánovas M. Protein acetylation affects acetate metabolism, motility and acid stress response in Escherichia coli. Mol Syst Biol 2014; 10:762. [PMID: 25518064 PMCID: PMC4299603 DOI: 10.15252/msb.20145227] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Although protein acetylation is widely observed, it has been associated with few specific
regulatory functions making it poorly understood. To interrogate its functionality, we analyzed the
acetylome in Escherichia coli knockout mutants of cobB, the only
known sirtuin-like deacetylase, and patZ, the best-known protein acetyltransferase.
For four growth conditions, more than 2,000 unique acetylated peptides, belonging to 809 proteins,
were identified and differentially quantified. Nearly 65% of these proteins are related to
metabolism. The global activity of CobB contributes to the deacetylation of a large number of
substrates and has a major impact on physiology. Apart from the regulation of acetyl-CoA synthetase,
we found that CobB-controlled acetylation of isocitrate lyase contributes to the fine-tuning of the
glyoxylate shunt. Acetylation of the transcription factor RcsB prevents DNA binding, activating
flagella biosynthesis and motility, and increases acid stress susceptibility. Surprisingly, deletion
of patZ increased acetylation in acetate cultures, which suggests that it regulates
the levels of acetylating agents. The results presented offer new insights into functional roles of
protein acetylation in metabolic fitness and global cell regulation.
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Affiliation(s)
- Sara Castaño-Cerezo
- Departamento de Bioquímica y Biología Molecular B e Inmunología, Facultad de Química, Universidad de Murcia Campus de Excelencia Mare Nostrum, Murcia, Spain
| | - Vicente Bernal
- Departamento de Bioquímica y Biología Molecular B e Inmunología, Facultad de Química, Universidad de Murcia Campus de Excelencia Mare Nostrum, Murcia, Spain
| | - Harm Post
- Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Tobias Fuhrer
- Institute of Molecular Systems Biology, ETH Zurich, Zurich, Switzerland
| | - Salvatore Cappadona
- Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Nerea C Sánchez-Díaz
- Departamento de Bioquímica y Biología Molecular B e Inmunología, Facultad de Química, Universidad de Murcia Campus de Excelencia Mare Nostrum, Murcia, Spain
| | - Uwe Sauer
- Institute of Molecular Systems Biology, ETH Zurich, Zurich, Switzerland
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands Netherlands Proteomics Center, Utrecht, The Netherlands
| | - A F Maarten Altelaar
- Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Manuel Cánovas
- Departamento de Bioquímica y Biología Molecular B e Inmunología, Facultad de Química, Universidad de Murcia Campus de Excelencia Mare Nostrum, Murcia, Spain
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49
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Arifin Y, Archer C, Lim S, Quek LE, Sugiarto H, Marcellin E, Vickers CE, Krömer JO, Nielsen LK. Escherichia coli W shows fast, highly oxidative sucrose metabolism and low acetate formation. Appl Microbiol Biotechnol 2014; 98:9033-44. [DOI: 10.1007/s00253-014-5956-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 07/07/2014] [Accepted: 07/08/2014] [Indexed: 10/24/2022]
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50
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Wang X, Xie Y, Gao P, Zhang S, Tan H, Yang F, Lian R, Tian J, Xu G. A metabolomics-based method for studying the effect of yfcC gene in Escherichia coli on metabolism. Anal Biochem 2014; 451:48-55. [DOI: 10.1016/j.ab.2014.01.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 01/07/2014] [Accepted: 01/21/2014] [Indexed: 10/25/2022]
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