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Li Y, Zhao X, Yao M, Yang W, Han Y, Liu L, Zhang J, Liu J. Mechanism of microbial production of acetoin and 2,3-butanediol optical isomers and substrate specificity of butanediol dehydrogenase. Microb Cell Fact 2023; 22:165. [PMID: 37644496 PMCID: PMC10466699 DOI: 10.1186/s12934-023-02163-6] [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: 06/08/2023] [Accepted: 07/31/2023] [Indexed: 08/31/2023] Open
Abstract
3-Hydroxybutanone (Acetoin, AC) and 2,3-butanediol (BD) are two essential four-carbon platform compounds with numerous pharmaceutical and chemical synthesis applications. AC and BD have two and three stereoisomers, respectively, while the application of the single isomer product in chemical synthesis is superior. AC and BD are glucose overflow metabolites produced by biological fermentation from a variety of microorganisms. However, the AC or BD produced by microorganisms using glucose is typically a mixture of various stereoisomers. This was discovered to be due to the simultaneous presence of multiple butanediol dehydrogenases (BDHs) in microorganisms, and AC and BD can be interconverted under BDH catalysis. In this paper, beginning with the synthesis pathways of microbial AC and BD, we review in detail the studies on the formation mechanisms of different stereoisomers of AC and BD, summarize the properties of different types of BDH that have been tabulated, and analyze the structural characteristics and affinities of different types of BDH by comparing them using literature and biological database data. Using microorganisms, recent research on the production of optically pure AC or BD was also reviewed. Limiting factors and possible solutions for chiral AC and BD production are discussed.
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Affiliation(s)
- Yuchen Li
- Shandong Food Ferment Industry Research & Design Institute, Qilu University of Technology, Shandong Academy of Sciences), Jinan, 250013, China
- School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China
| | - Xiangying Zhao
- Shandong Food Ferment Industry Research & Design Institute, Qilu University of Technology, Shandong Academy of Sciences), Jinan, 250013, China.
- School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China.
| | - Mingjing Yao
- Shandong Food Ferment Industry Research & Design Institute, Qilu University of Technology, Shandong Academy of Sciences), Jinan, 250013, China
| | - Wenli Yang
- Shandong Food Ferment Industry Research & Design Institute, Qilu University of Technology, Shandong Academy of Sciences), Jinan, 250013, China
- School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China
| | - Yanlei Han
- Shandong Food Ferment Industry Research & Design Institute, Qilu University of Technology, Shandong Academy of Sciences), Jinan, 250013, China
| | - Liping Liu
- Shandong Food Ferment Industry Research & Design Institute, Qilu University of Technology, Shandong Academy of Sciences), Jinan, 250013, China
- School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China
| | - Jiaxiang Zhang
- Shandong Food Ferment Industry Research & Design Institute, Qilu University of Technology, Shandong Academy of Sciences), Jinan, 250013, China
- School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China
| | - Jianjun Liu
- Shandong Food Ferment Industry Research & Design Institute, Qilu University of Technology, Shandong Academy of Sciences), Jinan, 250013, China
- School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China
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Barbato M, Palma E, Marzocchi U, Cruz Viggi C, Rossetti S, Aulenta F, Scoma A. Snorkels enhance alkanes respiration at ambient and increased hydrostatic pressure (10 MPa) by either supporting the TCA cycle or limiting alternative routes for acetyl-CoA metabolism. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 316:115244. [PMID: 35598451 DOI: 10.1016/j.jenvman.2022.115244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 04/27/2022] [Accepted: 05/05/2022] [Indexed: 06/15/2023]
Abstract
The impact of piezosensitive microorganisms is generally underestimated in the ecology of underwater environments exposed to increasing hydrostatic pressure (HP), including the biodegradation of crude oil components. Yet, no isolated pressure-loving (piezophile) microorganism grows optimally on hydrocarbons, and no isolated piezophile at all has a HP optimum <10 MPa (e.g. 1000 m below sea water level). Piezosensitive heterotrophs are thus largely accountable for oil clean up < 10 MPa, however, they are affected by such a mild HP increase in ways which are not completely clear. In a first study, the application of a bioelectrochemical system (called "oil-spill snorkel") enhanced the alkane oxidation capacity in sediments collected at surface water but tested up to 10 MPa. Here, the fingerprint left on transcript abundance was studied to explore which metabolic routes are 1) supported by snorkels application and 2) negatively impacted by HP increase. Transcript abundance was comparable for beta-oxidation across all treatments (also at a taxonomical level), while the metabolism of acetyl-CoA was highly impacted: at either 0.1 or 10 MPa, snorkels supported acetyl-CoA oxidation within the TCA cycle, while in negative controls using non-conductive rods several alternative routes for acetyl-CoA were stimulated (including those leading to internal carbon reserves e.g. 2,3 butanediol and dihydroxyacetone). In general, increased HP had opposite effects as compared to snorkels, thus indicating that snorkels could enhance hydrocarbons oxidation by alleviating in part the stressing effects imposed by increased HP on the anaerobic, respiratory electron transport chain. 16S rRNA gene analysis of sediments and biofilms on snorkels suggest a crosstalk between oil-degrading, sulfate-reducing microorganisms and sulfur oxidizers. In fact, no sulfur was deposited on snorkels, however, iron, aluminum and phosphorous were found to preferentially deposit on snorkels at 10 MPa. This data indicates that a passive BES such as the oil-spill snorkel can mitigate the stress imposed by increased HP on piezosensitive microorganisms (up to 10 MPa) without being subjected to passivation. An improved setup applying these principles can further support this deep-sea bioremediation strategy.
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Affiliation(s)
- Marta Barbato
- Engineered Microbial Systems (EMS) Lab, Industrial Biotechnology Section, Department of Biological and Chemical Engineering (BCE), Aarhus University, Aarhus, Denmark; Microbiology Section, Department of Biology, Aarhus University, Aarhus, Denmark
| | - Enza Palma
- Water Research Institute (IRSA), National Research Council (CNR), Monterotondo, Italy
| | - Ugo Marzocchi
- Center for Electromicrobiology, Section for Microbiology, Department of Biology, Aarhus University, Aarhus, Denmark; Center for Water Technology WATEC, Department of Biology, Aarhus University, Aarhus, Denmark
| | - Carolina Cruz Viggi
- Water Research Institute (IRSA), National Research Council (CNR), Monterotondo, Italy
| | - Simona Rossetti
- Water Research Institute (IRSA), National Research Council (CNR), Monterotondo, Italy
| | - Federico Aulenta
- Water Research Institute (IRSA), National Research Council (CNR), Monterotondo, Italy.
| | - Alberto Scoma
- Engineered Microbial Systems (EMS) Lab, Industrial Biotechnology Section, Department of Biological and Chemical Engineering (BCE), Aarhus University, Aarhus, Denmark; Microbiology Section, Department of Biology, Aarhus University, Aarhus, Denmark.
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Cui Z, Wang Z, Zheng M, Chen T. Advances in biological production of acetoin: a comprehensive overview. Crit Rev Biotechnol 2021; 42:1135-1156. [PMID: 34806505 DOI: 10.1080/07388551.2021.1995319] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Acetoin, a high-value-added bio-based platform chemical, is widely used in foods, cosmetics, agriculture, and the chemical industry. It is an important precursor for the synthesis of: 2,3-butanediol, liquid hydrocarbon fuels and heterocyclic compounds. Since the fossil resources are becoming increasingly scarce, biological production of acetoin has received increasing attention as an alternative to chemical synthesis. Although there are excellent reviews on the: application, catabolism and fermentative production of acetoin, little attention has been paid to acetoin production via: electrode-assisted fermentation, whole-cell biocatalysis, and in vitro/cell-free biocatalysis. In this review, acetoin biosynthesis pathways and relevant key enzymes are firstly reviewed. In addition, various strategies for biological acetoin production are summarized including: cell-free biocatalysis, whole-cell biocatalysis, microbial fermentation, and electrode-assisted fermentation. The advantages and disadvantages of the different approaches are discussed and weighed, illustrating the increasing progress toward economical, green and efficient production of acetoin. Additionally, recent advances in acetoin extraction and recovery in downstream processing are also briefly reviewed. Moreover, the current issues and future prospects of diverse strategies for biological acetoin production are discussed, with the hope of realizing the promises of industrial acetoin biomanufacturing in the near future.
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Affiliation(s)
- Zhenzhen Cui
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, China
| | - Zhiwen Wang
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, China
| | - Meiyu Zheng
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, China
| | - Tao Chen
- Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, China
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Lee JW, Lee YG, Jin YS, Rao CV. Metabolic engineering of non-pathogenic microorganisms for 2,3-butanediol production. Appl Microbiol Biotechnol 2021; 105:5751-5767. [PMID: 34287658 DOI: 10.1007/s00253-021-11436-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/01/2021] [Accepted: 06/17/2021] [Indexed: 12/12/2022]
Abstract
2,3-Butanediol (2,3-BDO) is a promising commodity chemical with various industrial applications. While petroleum-based chemical processes currently dominate the industrial production of 2,3-BDO, fermentation-based production of 2,3-BDO provides an attractive alternative to chemical-based processes with regards to economic and environmental sustainability. The achievement of high 2,3-BDO titer, yield, and productivity in microbial fermentation is a prerequisite for the production of 2,3-BDO at large scales. Also, enantiopure production of 2,3-BDO production is desirable because 2,3-BDO stereoisomers have unique physicochemical properties. Pursuant to these goals, many metabolic engineering strategies to improve 2,3-BDO production from inexpensive sugars by Klebsiella oxytoca, Bacillus species, and Saccharomyces cerevisiae have been developed. This review summarizes the recent advances in metabolic engineering of non-pathogenic microorganisms to enable efficient and enantiopure production of 2,3-BDO. KEY POINTS: • K. oxytoca, Bacillus species, and S. cerevisiae have been engineered to achieve efficient 2,3-BDO production. • Metabolic engineering of non-pathogenic microorganisms enabled enantiopure production of 2,3-BDO. • Cost-effective 2,3-BDO production can be feasible by using renewable biomass.
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Affiliation(s)
- Jae Won Lee
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Ye-Gi Lee
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Yong-Su Jin
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Christopher V Rao
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA. .,DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA. .,Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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C4 Bacterial Volatiles Improve Plant Health. Pathogens 2021; 10:pathogens10060682. [PMID: 34072921 PMCID: PMC8227687 DOI: 10.3390/pathogens10060682] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/10/2021] [Accepted: 05/24/2021] [Indexed: 02/04/2023] Open
Abstract
Plant growth-promoting rhizobacteria (PGPR) associated with plant roots can trigger plant growth promotion and induced systemic resistance. Several bacterial determinants including cell-wall components and secreted compounds have been identified to date. Here, we review a group of low-molecular-weight volatile compounds released by PGPR, which improve plant health, mostly by protecting plants against pathogen attack under greenhouse and field conditions. We particularly focus on C4 bacterial volatile compounds (BVCs), such as 2,3-butanediol and acetoin, which have been shown to activate the plant immune response and to promote plant growth at the molecular level as well as in large-scale field applications. We also disc/ uss the potential applications, metabolic engineering, and large-scale fermentation of C4 BVCs. The C4 bacterial volatiles act as airborne signals and therefore represent a new type of biocontrol agent. Further advances in the encapsulation procedure, together with the development of standards and guidelines, will promote the application of C4 volatiles in the field.
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Purification and Characterization of (2R,3R)-2,3-Butanediol Dehydrogenase of the Human Pathogen Neisseria gonorrhoeae FA1090 Produced in Escherichia coli. Mol Biotechnol 2021; 63:491-501. [PMID: 33763825 DOI: 10.1007/s12033-021-00308-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Accepted: 02/12/2021] [Indexed: 12/22/2022]
Abstract
2,3-Butanediol dehydrogenase (BDH), also known as acetoin/diacetyl reductase, is a pivotal enzyme for the formation of 2,3-butanediol (2,3-BD), a chiral compound with potential roles in the virulence of certain pathogens. Here, a NAD(H)-dependent (2R,3R)-BDH from Neisseria gonorrhoeae FA1090 (NgBDH), the causative agent of gonorrhoea, was functionally characterized. Sequence analysis indicated that it belongs to zinc-containing medium-chain dehydrogenase/reductase family. The recombinant NgBDH migrated as a single band with a size of around 45 kDa on SDS-PAGE and could be confirmed by Western blotting and mass spectrometry. For the oxidation of either (2R,3R)-2,3-BD or meso-2,3-BD, the enzyme exhibited a broad pH optimum between pH 9.5 to 11.5. For the reduction of (3R/3S)-acetoin, the pH optimum was around 6.5. The enzyme could catalyze the stereospecific oxidation of (2R,3R)-2,3-BD (Km = 0.16 mM, kcat/Km = 673 s-1 · mM-1) and meso-BD (Km = 0.72 mM, kcat/Km = 165 s-1 · mM-1). Moreover, it could also reduce (3R/3S)-acetoin with a Km of 0.14 mM and a kcat/Km of 885 s-1 · mM-1. The results presented here contribute to understand the 2,3-BD metabolism in N. gonorrhoeae and pave the way for studying the influence of 2,3-BD metabolism on the virulence of this pathogen in the future.
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Increasing biohydrogen production with the use of a co-culture inside a microbial electrolysis cell. Biochem Eng J 2020. [DOI: 10.1016/j.bej.2020.107802] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Silvetti T, Morandi S, Brasca M. Growth factors affecting gas production and reduction potential of vegetative cell and spore inocula of dairy-related Clostridium species. Lebensm Wiss Technol 2018. [DOI: 10.1016/j.lwt.2018.02.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Lee SJ, Choi HS, Kim CK, Thapa LP, Park C, Kim SW. Process strategy for 2,3-butanediol production in fed-batch culture by acetate addition. J IND ENG CHEM 2017. [DOI: 10.1016/j.jiec.2017.07.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Hu J, Lei P, Mohsin A, Liu X, Huang M, Li L, Hu J, Hang H, Zhuang Y, Guo M. Mixomics analysis of Bacillus subtilis: effect of oxygen availability on riboflavin production. Microb Cell Fact 2017; 16:150. [PMID: 28899391 PMCID: PMC5596917 DOI: 10.1186/s12934-017-0764-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 09/07/2017] [Indexed: 12/14/2022] Open
Abstract
Background Riboflavin, an intermediate of primary metabolism, is one kind of important food additive with high economic value. The microbial cell factory Bacillus subtilis has already been proven to possess significant importance for the food industry and have become one of the most widely used riboflavin-producing strains. In the practical fermentation processes, a sharp decrease in riboflavin production is encountered along with a decrease in the dissolved oxygen (DO) tension. Influence of this oxygen availability on riboflavin biosynthesis through carbon central metabolic pathways in B. subtilis is unknown so far. Therefore the unveiled effective metabolic pathways were still an unaccomplished task till present research work. Results In this paper, the microscopic regulation mechanisms of B. subtilis grown under different dissolved oxygen tensions were studied by integrating 13C metabolic flux analysis, metabolomics and transcriptomics. It was revealed that the glucose metabolic flux through pentose phosphate (PP) pathway was lower as being confirmed by smaller pool sizes of metabolites in PP pathway and lower expression amount of ykgB at transcriptional level. The latter encodes 6-phosphogluconolactonase (6-PGL) under low DO tension. In response to low DO tension in broth, the glucose metabolic flux through Embden–Meyerhof–Parnas (EMP) pathway was higher and the gene, alsS, encoding for acetolactate synthase was significantly activated that may result due to lower ATP concentration and higher NADH/NAD+ ratio. Moreover, ResE, a membrane-anchored protein that is capable of oxygen regulated phosphorylase activity, and ResD, a regulatory protein that can be phosphorylated and dephosphorylated by ResE, were considered as DO tension sensor and transcriptional regulator respectively. Conclusions This study shows that integration of transcriptomics, 13C metabolic flux analysis and metabolomics analysis provides a comprehensive understanding of biosynthesized riboflavin’s regulatory mechanisms in B. subtilis grown under different dissolved oxygen tension conditions. The two-component system, ResD–ResE, was considered as the signal receiver of DO tension and gene regulator that led to differences between biomass and riboflavin production after triggering the shifts in gene expression, metabolic flux distributions and metabolite pool sizes. Electronic supplementary material The online version of this article (doi:10.1186/s12934-017-0764-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Junlang Hu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Rd., P.O. box 329#, Shanghai, 200237, People's Republic of China
| | - Pan Lei
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Rd., P.O. box 329#, Shanghai, 200237, People's Republic of China
| | - Ali Mohsin
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Rd., P.O. box 329#, Shanghai, 200237, People's Republic of China
| | - Xiaoyun Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Rd., P.O. box 329#, Shanghai, 200237, People's Republic of China
| | - Mingzhi Huang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Rd., P.O. box 329#, Shanghai, 200237, People's Republic of China.
| | - Liang Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Rd., P.O. box 329#, Shanghai, 200237, People's Republic of China
| | - Jianhua Hu
- Shanghai Acebright Pharmaceuticals Group Co., Ltd, Shanghai, 201203, People's Republic of China
| | - Haifeng Hang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Rd., P.O. box 329#, Shanghai, 200237, People's Republic of China
| | - Yingping Zhuang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Rd., P.O. box 329#, Shanghai, 200237, People's Republic of China
| | - Meijin Guo
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Rd., P.O. box 329#, Shanghai, 200237, People's Republic of China.
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Jung HM, Kim YH, Oh MK. Formate and Nitrate Utilization in Enterobacter aerogenes for Semi-Anaerobic Production of Isobutanol. Biotechnol J 2017; 12. [PMID: 28731532 DOI: 10.1002/biot.201700121] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 07/07/2017] [Indexed: 11/07/2022]
Abstract
Anaerobic bioprocessing is preferred because of its economic advantages. However, low productivity and decreased growth of the host strain have limited the use of the anaerobic process. Anaerobic respiration can be applied to anoxic processing using formate and nitrate metabolism to improve the productivity of value-added metabolites. A isobutanol-producing strains is constructed using Enterobacter aerogenes as a host strain by metabolic engineering approaches. The byproduct pathway (ldhA, budA, and pflB) is knocked out, and heterologous keto-acid decarboxylase (kivD) and alcohol dehydrogenase (adhA) are expressed along with the L-valine synthesis pathway (ilvCD and budB). The pyruvate formate-lyase mutant shows decreased growth rates when cultivated in semi-anaerobic conditions, which results in a decline in productivity. When formate and nitrate are supplied in the culture medium, the growth rates and amount of isobutanol production is restored (4.4 g L-1 , 0.23 g g-1 glucose, 0.18 g L-1 h-1 ). To determine the function of the formate and nitrate coupling reaction system, the mutant strains that could not utilize formate or nitrate is contructed. Decreased growth and productivity are observed in the nitrate reductase (narG) mutant strain. This is the first report of engineering isobutanol-producing E. aerogenes to increase strain fitness via augmentation of formate and nitrate metabolism during anaerobic cultivation.
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Affiliation(s)
- Hwi-Min Jung
- Department of Chemical and Biological Engineering, Korea University, Seoul, Korea
| | - Yong Hwan Kim
- School of Energy and Chemical Engineering, UNIST, Ulsan, Korea
| | - Min-Kyu Oh
- Department of Chemical and Biological Engineering, Korea University, Seoul, Korea
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Okonkwo CC, Ujor V, Ezeji TC. Investigation of relationship between 2,3-butanediol toxicity and production during growth of Paenibacillus polymyxa. N Biotechnol 2017; 34:23-31. [DOI: 10.1016/j.nbt.2016.10.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 10/06/2016] [Accepted: 10/14/2016] [Indexed: 10/20/2022]
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Hugouvieux-Cotte-Pattat N. Metabolism and Virulence Strategies in Dickeya-Host Interactions. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016; 142:93-129. [PMID: 27571693 DOI: 10.1016/bs.pmbts.2016.05.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Dickeya, a genus of the Enterobacteriaceae family, all cause plant diseases. They are aggressive necrotrophs that have both a wide geographic distribution and a wide host range. As a plant pathogen, Dickeya has had to adapt to a vegetarian diet. Plants constitute a large storage of carbohydrates; they contain substantial amounts of soluble sugars and the plant cell wall is composed of long polysaccharides. Metabolic functions used by Dickeya in order to multiply during infection are essential aspects of pathogenesis. Dickeya is able to catabolize a large range of oligosaccharides and glycosides of plant origin. Glucose, fructose, and sucrose are all efficiently metabolized by the bacteria. To avoid the formation of acidic products, their final catabolism involves the butanediol pathway, a nonacidifying fermentative pathway. The assimilation of plant polysaccharides necessitates their prior cleavage into oligomers. Notably, the Dickeya virulence strategy is based on its capacity to dissociate the plant cell wall and, for this, the bacteria secrete an extensive set of polysaccharide degrading enzymes, composed mostly of pectinases. Since pectic polymers have a major role in plant tissue cohesion, pectinase action results in plant rot. The pectate lyases secreted by Dickeya play a double role as virulence factors and as nutrient providers. This dual function implies that the pel gene expression is regulated by both metabolic and virulence regulators. The control of sugar assimilation by specific or global regulators enables Dickeya to link its nutritional status to virulence, a coupling that optimizes the different phases of infection.
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Affiliation(s)
- N Hugouvieux-Cotte-Pattat
- Microbiology Adaptation and Pathogenesis, CNRS, University of Lyon, University Claude Bernard Lyon 1, INSA Lyon, Villeurbanne, France.
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Yi HS, Ahn YR, Song GC, Ghim SY, Lee S, Lee G, Ryu CM. Impact of a Bacterial Volatile 2,3-Butanediol on Bacillus subtilis Rhizosphere Robustness. Front Microbiol 2016; 7:993. [PMID: 27446033 PMCID: PMC4923110 DOI: 10.3389/fmicb.2016.00993] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 06/09/2016] [Indexed: 12/16/2022] Open
Abstract
Volatile compounds, such as short chain alcohols, acetoin, and 2,3-butanediol, produced by certain strains of root-associated bacteria (rhizobacteria) elicit induced systemic resistance in plants. The effects of bacterial volatile compounds (BVCs) on plant and fungal growth have been extensively studied; however, the impact of bacterial BVCs on bacterial growth remains poorly understood. In this study the effects of a well-characterized bacterial volatile, 2,3-butanediol, produced by the rhizobacterium Bacillus subtilis, were examined in the rhizosphere. The nature of 2,3-butanediol on bacterial cells was assessed, and the effect of the molecule on root colonization was also determined. Pepper roots were inoculated with three B. subtilis strains: the wild type, a 2,3-butanediol overexpressor, and a 2,3-butanediol null mutant. The B. subtilis null strain was the first to be eliminated in the rhizosphere, followed by the wild-type strain. The overexpressor mutant was maintained at roots for the duration of the experiment. Rhizosphere colonization by a saprophytic fungus declined from 14 days post-inoculation in roots treated with the B. subtilis overexpressor strain. Next, exudates from roots exposed to 2,3-butanediol were assessed for their impact on fungal and bacterial growth in vitro. Exudates from plant roots pre-treated with the 2,3-butanediol overexpressor were used to challenge various microorganisms. Growth was inhibited in a saprophytic fungus (Trichoderma sp.), the 2,3-butanediol null B. subtilis strain, and a soil-borne pathogen, Ralstonia solanacearum. Direct application of 2,3-butanediol to pepper roots, followed by exposure to R. solanacearum, induced expression of Pathogenesis-Related (PR) genes such as CaPR2, CaSAR8.2, and CaPAL. These results indicate that 2,3-butanediol triggers the secretion of root exudates that modulate soil fungi and rhizosphere bacteria. These data broaden our knowledge regarding bacterial volatiles in the rhizosphere and their roles in bacterial fitness and as important inducers of plant defenses.
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Affiliation(s)
- Hwe-Su Yi
- Molecular Phytobacteriology Laboratory, Korea Research Institute of Bioscience and Biotechnology, DaejeonSouth Korea; School of Life Science, Kyungpook National University, DaeguSouth Korea
| | - Yeo-Rim Ahn
- Molecular Phytobacteriology Laboratory, Korea Research Institute of Bioscience and Biotechnology, DaejeonSouth Korea; Department of Biological Science, Korea Advanced Institute of Science and Technology, DaejeonSouth Korea
| | - Geun C Song
- Molecular Phytobacteriology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Daejeon South Korea
| | - Sa-Youl Ghim
- School of Life Science, Kyungpook National University, Daegu South Korea
| | - Soohyun Lee
- Molecular Phytobacteriology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Daejeon South Korea
| | - Gahyung Lee
- Molecular Phytobacteriology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Daejeon South Korea
| | - Choong-Min Ryu
- Molecular Phytobacteriology Laboratory, Korea Research Institute of Bioscience and Biotechnology, DaejeonSouth Korea; Biosystems and Bioengineering Program, School of Science, University of Science and Technology, DaejeonSouth Korea
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15
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Zhang L, Xu Y, Gao J, Xu H, Cao C, Xue F, Ding G, Peng Y. Introduction of the exogenous NADH coenzyme regeneration system and its influence on intracellular metabolic flux of Paenibacillus polymyxa. BIORESOURCE TECHNOLOGY 2016; 201:319-328. [PMID: 26687492 DOI: 10.1016/j.biortech.2015.11.067] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 11/22/2015] [Accepted: 11/24/2015] [Indexed: 06/05/2023]
Abstract
The NAD(+)-dependent formate dehydrogenase (FDH) gene from Candida boidinii was introduced into Paenibacillus polymyxa ZJ-9. The effects of this exogenous gene on the growth of the recombinant strain P. polymyxa XG-1, FDH activity, intracellular NADH and NAD(+) level and the synthesis of R,R-2,3-butanediol (R,R-2,3-BD) were determined. Results from the fermentation in the 7.5L bioreactor showed that the exogenous FDH was highly expressed in the recombinant strain. The titers of NADH, lactic acid, ethanol, NADH/NAD(+), and CO2 excretion rate (CER) of the recombinant strain increased considerably, while acetoin and formic acid decreased significantly. The highest titers of R,R-2,3-BD by the recombinant strain in batch and fed-batch fermentation were 36.8g/L and 51.3g/L, increased 10.2% and 8.0% compared with the parent strain, respectively. This study confirmed that coenzyme regeneration system can manipulate substance metabolism in bacteria, and is an efficient way for promoting the synthesis of NADH-dependent products.
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Affiliation(s)
- Li Zhang
- School of Marine and Bioengineering, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Youyong Xu
- School of Marine and Bioengineering, Yancheng Institute of Technology, Yancheng 224051, PR China; State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing University of Technology, Nanjing 211816, PR China
| | - Jian Gao
- School of Marine and Bioengineering, Yancheng Institute of Technology, Yancheng 224051, PR China.
| | - Hong Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing University of Technology, Nanjing 211816, PR China
| | - Can Cao
- School of Marine and Bioengineering, Yancheng Institute of Technology, Yancheng 224051, PR China; State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing University of Technology, Nanjing 211816, PR China
| | - Feng Xue
- School of Marine and Bioengineering, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Ge Ding
- School of Marine and Bioengineering, Yancheng Institute of Technology, Yancheng 224051, PR China
| | - Yingyun Peng
- School of Marine and Bioengineering, Yancheng Institute of Technology, Yancheng 224051, PR China
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16
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Abstract
Pyruvate and acetyl-CoA form the backbone of central metabolism. The nonoxidative cleavage of pyruvate to acetyl-CoA and formate by the glycyl radical enzyme pyruvate formate lyase is one of the signature reactions of mixed-acid fermentation in enterobacteria. Under these conditions, formic acid accounts for up to one-third of the carbon derived from glucose. The further metabolism of acetyl-CoA to acetate via acetyl-phosphate catalyzed by phosphotransacetylase and acetate kinase is an exemplar of substrate-level phosphorylation. Acetyl-CoA can also be used as an acceptor of the reducing equivalents generated during glycolysis, whereby ethanol is formed by the polymeric acetaldehyde/alcohol dehydrogenase (AdhE) enzyme. The metabolism of acetyl-CoA via either the acetate or the ethanol branches is governed by the cellular demand for ATP and the necessity to reoxidize NADH. Consequently, in the absence of an electron acceptor mutants lacking either branch of acetyl-CoA metabolism fail to cleave pyruvate, despite the presence of PFL, and instead reduce it to D-lactate by the D-lactate dehydrogenase. The conversion of PFL to the active, radical-bearing species is controlled by a radical-SAM enzyme, PFL-activase. All of these reactions are regulated in response to the prevalent cellular NADH:NAD+ ratio. In contrast to Escherichia coli and Salmonella species, some genera of enterobacteria, e.g., Klebsiella and Enterobacter, produce the more neutral product 2,3-butanediol and considerable amounts of CO2 as fermentation products. In these bacteria, two molecules of pyruvate are converted to α-acetolactate (AL) by α-acetolactate synthase (ALS). AL is then decarboxylated and subsequently reduced to the product 2,3-butandiol.
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Zhao H, Yun J. Isolation, identification and fermentation conditions of highly acetoin-producing acetic acid bacterium from Liangzhou fumigated vinegar in China. ANN MICROBIOL 2015. [DOI: 10.1007/s13213-015-1106-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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18
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Jantama K, Polyiam P, Khunnonkwao P, Chan S, Sangproo M, Khor K, Jantama SS, Kanchanatawee S. Efficient reduction of the formation of by-products and improvement of production yield of 2,3-butanediol by a combined deletion of alcohol dehydrogenase, acetate kinase-phosphotransacetylase, and lactate dehydrogenase genes in metabolically engineered Klebsiella oxytoca in mineral salts medium. Metab Eng 2015; 30:16-26. [PMID: 25895450 DOI: 10.1016/j.ymben.2015.04.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 03/18/2015] [Accepted: 04/08/2015] [Indexed: 11/24/2022]
Abstract
Klebsiella oxytoca KMS005 (∆adhE∆ackA-pta∆ldhA) was metabolically engineered to improve 2,3-butanediol (BDO) yield. Elimination of alcohol dehydrogenase E (adhE), acetate kinase A-phosphotransacetylase (ackA-pta), and lactate dehydrogenase A (ldhA) enzymes allowed BDO production as a primary pathway for NADH re-oxidation, and significantly reduced by-products. KMS005 was screened for the efficient glucose utilization by metabolic evolution. KMS005-73T improved BDO production at a concentration of 23.5±0.5 g/L with yield of 0.46±0.02 g/g in mineral salts medium containing 50 g/L glucose in a shake flask. KMS005-73T also exhibited BDO yields of about 0.40-0.42 g/g from sugarcane molasses, cassava starch, and maltodextrin. During fed-batch fermentation, KMS005-73T produced BDO at a concentration, yield, and overall and specific productivities of 117.4±4.5 g/L, 0.49±0.02 g/g, 1.20±0.05 g/Lh, and 27.2±1.1 g/gCDW, respectively. No acetoin, lactate, and formate were detected, and only trace amounts of acetate and ethanol were formed. The strain also produced the least by-products and the highest BDO yield among other Klebsiella strains previously developed.
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Affiliation(s)
- Kaemwich Jantama
- Metabolic Engineering Research Unit, School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, 111 University Avenue, Suranaree Sub-District, Muang District, 30000 Nakhon Ratchasima, Thailand.
| | - Pattharasedthi Polyiam
- Metabolic Engineering Research Unit, School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, 111 University Avenue, Suranaree Sub-District, Muang District, 30000 Nakhon Ratchasima, Thailand
| | - Panwana Khunnonkwao
- Metabolic Engineering Research Unit, School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, 111 University Avenue, Suranaree Sub-District, Muang District, 30000 Nakhon Ratchasima, Thailand
| | - Sitha Chan
- Metabolic Engineering Research Unit, School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, 111 University Avenue, Suranaree Sub-District, Muang District, 30000 Nakhon Ratchasima, Thailand
| | - Maytawadee Sangproo
- Metabolic Engineering Research Unit, School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, 111 University Avenue, Suranaree Sub-District, Muang District, 30000 Nakhon Ratchasima, Thailand
| | - Kirin Khor
- Metabolic Engineering Research Unit, School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, 111 University Avenue, Suranaree Sub-District, Muang District, 30000 Nakhon Ratchasima, Thailand
| | - Sirima Suvarnakuta Jantama
- Division of Biopharmacy, Faculty of Pharmaceutical Sciences, Ubon Ratchathani University, Warinchamrap, Ubon Ratchathani 34190, Thailand
| | - Sunthorn Kanchanatawee
- Metabolic Engineering Research Unit, School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, 111 University Avenue, Suranaree Sub-District, Muang District, 30000 Nakhon Ratchasima, Thailand
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Vivijs B, Haberbeck LU, Baiye Mfortaw Mbong V, Bernaerts K, Geeraerd AH, Aertsen A, Michiels CW. Formate hydrogen lyase mediates stationary-phase deacidification and increases survival during sugar fermentation in acetoin-producing enterobacteria. Front Microbiol 2015; 6:150. [PMID: 25762991 PMCID: PMC4340222 DOI: 10.3389/fmicb.2015.00150] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 02/09/2015] [Indexed: 12/02/2022] Open
Abstract
Two fermentation types exist in the Enterobacteriaceae family. Mixed-acid fermenters produce substantial amounts of lactate, formate, acetate, and succinate, resulting in lethal medium acidification. On the other hand, 2,3-butanediol fermenters switch to the production of the neutral compounds acetoin and 2,3-butanediol and even deacidify the environment after an initial acidification phase, thereby avoiding cell death. We equipped three mixed-acid fermenters (Salmonella Typhimurium, S. Enteritidis and Shigella flexneri) with the acetoin pathway from Serratia plymuthica to investigate the mechanisms of deacidification. Acetoin production caused attenuated acidification during exponential growth in all three bacteria, but stationary-phase deacidification was only observed in Escherichia coli and Salmonella, suggesting that it was not due to the consumption of protons accompanying acetoin production. To identify the mechanism, 34 transposon mutants of acetoin-producing E. coli that no longer deacidified the culture medium were isolated. The mutations mapped to 16 genes, all involved in formate metabolism. Formate is an end product of mixed-acid fermentation that can be converted to H2 and CO2 by the formate hydrogen lyase (FHL) complex, a reaction that consumes protons and thus can explain medium deacidification. When hycE, encoding the large subunit of hydrogenase 3 that is part of the FHL complex, was deleted in acetoin-producing E. coli, deacidification capacity was lost. Metabolite analysis in E. coli showed that introduction of the acetoin pathway reduced lactate and acetate production, but increased glucose consumption and formate and ethanol production. Analysis of a hycE mutant in S. plymuthica confirmed that medium deacidification in this organism is also mediated by FHL. These findings improve our understanding of the physiology and function of fermentation pathways in Enterobacteriaceae.
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Affiliation(s)
- Bram Vivijs
- Laboratory of Food Microbiology and Leuven Food Science and Nutrition Research Centre, Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering, KU Leuven Leuven, Belgium
| | - Leticia U Haberbeck
- Laboratory of Food Microbiology and Leuven Food Science and Nutrition Research Centre, Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering, KU Leuven Leuven, Belgium ; Division of Mechatronics, Biostatistics and Sensors, Department of Biosystems, Faculty of Bioscience Engineering, KU Leuven Leuven, Belgium
| | - Victor Baiye Mfortaw Mbong
- Division of Mechatronics, Biostatistics and Sensors, Department of Biosystems, Faculty of Bioscience Engineering, KU Leuven Leuven, Belgium
| | - Kristel Bernaerts
- Chemical and Biochemical Process Technology and Control Section, Department of Chemical Engineering, Faculty of Engineering Science KU Leuven, Leuven, Belgium
| | - Annemie H Geeraerd
- Division of Mechatronics, Biostatistics and Sensors, Department of Biosystems, Faculty of Bioscience Engineering, KU Leuven Leuven, Belgium
| | - Abram Aertsen
- Laboratory of Food Microbiology and Leuven Food Science and Nutrition Research Centre, Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering, KU Leuven Leuven, Belgium
| | - Chris W Michiels
- Laboratory of Food Microbiology and Leuven Food Science and Nutrition Research Centre, Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering, KU Leuven Leuven, Belgium
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20
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Vivijs B, Moons P, Aertsen A, Michiels CW. Acetoin synthesis acquisition favors Escherichia coli growth at low pH. Appl Environ Microbiol 2014; 80:6054-61. [PMID: 25063653 PMCID: PMC4178668 DOI: 10.1128/aem.01711-14] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 07/17/2014] [Indexed: 11/20/2022] Open
Abstract
Some members of the family Enterobacteriaceae ferment sugars via the mixed-acid fermentation pathway. This yields large amounts of acids, causing strong and sometimes even lethal acidification of the environment. Other family members employ the 2,3-butanediol fermentation pathway, which generates comparatively less acidic and more neutral end products, such as acetoin and 2,3-butanediol. In this work, we equipped Escherichia coli MG1655 with the budAB operon, encoding the acetoin pathway, from Serratia plymuthica RVH1 and investigated how this affected the ability of E. coli to cope with acid stress during growth. Acetoin fermentation prevented lethal medium acidification by E. coli in lysogeny broth (LB) supplemented with glucose. It also supported growth and higher stationary-phase cell densities in acidified LB broth with glucose (pH 4.10 to 4.50) and in tomato juice (pH 4.40 to 5.00) and reduced the minimal pH at which growth could be initiated. On the other hand, the acetoin-producing strain was outcompeted by the nonproducer in a mixed-culture experiment at low pH, suggesting a fitness cost associated with acetoin production. Finally, we showed that acetoin production profoundly changes the appearance of E. coli on several diagnostic culture media. Natural E. coli strains that have laterally acquired budAB genes may therefore have escaped detection thus far. This study demonstrates the potential importance of acetoin fermentation in the ecology of E. coli in the food chain and contributes to a better understanding of the microbiological stability and safety of acidic foods.
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Affiliation(s)
- Bram Vivijs
- Laboratory of Food Microbiology and Leuven Food Science and Nutrition Research Centre (LFoRCe), Department of Microbial and Molecular Systems (MS), Faculty of Bioscience Engineering, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Pieter Moons
- Laboratory of Food Microbiology and Leuven Food Science and Nutrition Research Centre (LFoRCe), Department of Microbial and Molecular Systems (MS), Faculty of Bioscience Engineering, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Abram Aertsen
- Laboratory of Food Microbiology and Leuven Food Science and Nutrition Research Centre (LFoRCe), Department of Microbial and Molecular Systems (MS), Faculty of Bioscience Engineering, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Chris W Michiels
- Laboratory of Food Microbiology and Leuven Food Science and Nutrition Research Centre (LFoRCe), Department of Microbial and Molecular Systems (MS), Faculty of Bioscience Engineering, Katholieke Universiteit Leuven, Leuven, Belgium
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21
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Study of the role of anaerobic metabolism in succinate production by Enterobacter aerogenes. Appl Microbiol Biotechnol 2014; 98:7803-13. [PMID: 24962116 DOI: 10.1007/s00253-014-5884-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 06/04/2014] [Accepted: 06/05/2014] [Indexed: 10/25/2022]
Abstract
Succinate is a core biochemical building block; optimizing succinate production from biomass by microbial fermentation is a focus of basic and applied biotechnology research. Lowering pH in anaerobic succinate fermentation culture is a cost-effective and environmentally friendly approach to reducing the use of sub-raw materials such as alkali, which are needed for neutralization. To evaluate the potential of bacteria-based succinate fermentation under weak acidic (pH <6.2) and anaerobic conditions, we characterized the anaerobic metabolism of Enterobacter aerogenes AJ110637, which rapidly assimilates glucose at pH 5.0. Based on the profile of anaerobic products, we constructed single-gene knockout mutants to eliminate the main anaerobic metabolic pathways involved in NADH re-oxidation. These single-gene knockout studies showed that the ethanol synthesis pathway serves as the dominant NADH re-oxidation pathway in this organism. To generate a metabolically engineered strain for succinate production, we eliminated ethanol formation and introduced a heterogeneous carboxylation enzyme, yielding E. aerogenes strain ΔadhE/PCK. The strain produced succinate from glucose with a 60.5% yield (grams of succinate produced per gram of glucose consumed) at pH <6.2 and anaerobic conditions. Thus, we showed the potential of bacteria-based succinate fermentation under weak acidic conditions.
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2,3-Butanediol fermentation promotes growth of Serratia plymuthica at low pH but not survival of extreme acid challenge. Int J Food Microbiol 2014; 175:36-44. [DOI: 10.1016/j.ijfoodmicro.2014.01.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 01/23/2014] [Accepted: 01/26/2014] [Indexed: 01/10/2023]
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Gao J, Xu YY, Li FW, Ding G. Production of S-acetoin from diacetyl by Escherichia coli transformant cells that express the diacetyl reductase gene of Paenibacillus polymyxa ZJ-9. Lett Appl Microbiol 2013; 57:274-81. [PMID: 23701367 DOI: 10.1111/lam.12107] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 05/16/2013] [Accepted: 05/18/2013] [Indexed: 12/01/2022]
Abstract
UNLABELLED S-acetoin (S-AC) is an important four-carbon chiral compound that has unique industrial applications in the asymmetric synthesis of valuable chiral specialty chemicals. However, previous studies showed that the usually low yield and optical purity of S-AC as well as the very high substrate cost have hindered the application of this compound. In the current work, a gene encoding diacetyl reductase (DAR) from a Paenibacillus polymyxa strain ZJ-9 was cloned and expressed in Escherichia coli. Whole cells of the recombinant E. coli were used to produce S-AC from diacetyl (DA). Under optimal conditions, S-AC with high optical purity (purity >99·9%) was obtained with a yield of 13·5 ± 0·24 and 39·4 ± 0·38 g l(-1) under batch and fed-batch culture conditions, respectively. This process featured the biotransformation of DA into S-AC using whole cells of engineered E. coli. The result is a considerable increase in the yield and optical purity of S-AC, which in turn facilitated the practical application of the compound. SIGNIFICANCE AND IMPACT OF THE STUDY This study demonstrated a highly efficient new method to produce S-acetoin with higher than 99·9% optical purity from diacetyl using whole cells of engineered Escherichia coli. It will therefore decrease the production cost of S-acetoin and highlight its application in asymmetric synthesis of highly valuable chiral compounds.
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Affiliation(s)
- J Gao
- Schol of Chemical and Biological Engineering, Yancheng Institute of Technology, Yancheng, China
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24
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Mazumdar S, Lee J, Oh MK. Microbial production of 2,3 butanediol from seaweed hydrolysate using metabolically engineered Escherichia coli. BIORESOURCE TECHNOLOGY 2013; 136:329-36. [PMID: 23567699 DOI: 10.1016/j.biortech.2013.03.013] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 03/01/2013] [Accepted: 03/04/2013] [Indexed: 05/20/2023]
Abstract
A variety of biofuel and biorefinery products have been produced from engineered Escherichia coli till date. Most of these products had been derived from simple sugars in its pure form, rather than deriving it from alternative, renewable and carbon neutral sources, such as marine alga biomass. Engineering E. coli to use algal hydrolysate can make these an attractive carbon source for the industrial production of value added fuels and chemicals. This work reports the engineering of E. coli by a combination of gene deletion and synthetic pathway incorporation, for the efficient utilization of algal hydrolysate to produce BA (2,3 butanediol+acetoin) under microaerobic condition. Engineered strain produced ~19 g/L of total BA from algal hydrolysate in defined M9 salt media at a yield of 0.43 g/g.
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Affiliation(s)
- Suman Mazumdar
- Department of Chemical and Biological Engineering, Korea University, Seoul, Republic of Korea
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Ji XJ, Xia ZF, Fu NH, Nie ZK, Shen MQ, Tian QQ, Huang H. Cofactor engineering through heterologous expression of an NADH oxidase and its impact on metabolic flux redistribution in Klebsiella pneumoniae. BIOTECHNOLOGY FOR BIOFUELS 2013; 6:7. [PMID: 23351660 PMCID: PMC3563507 DOI: 10.1186/1754-6834-6-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 01/23/2013] [Indexed: 05/10/2023]
Abstract
BACKGROUND Acetoin is an important bio-based platform chemical. However, it is usually existed as a minor byproduct of 2,3-butanediol fermentation in bacteria. RESULTS The present study reports introducing an exogenous NAD+ regeneration sysytem into a 2,3-butanediol producing strain Klebsiella pneumoniae to increse the accumulation of acetoin. Batch fermentation suggested that heterologous expression of the NADH oxidase in K. pneumoniae resulted in large decreases in the intracellular NADH concentration (1.4 fold) and NADH/NAD+ ratio (2.0 fold). Metabolic flux analysis revealed that fluxes to acetoin and acetic acid were enhanced, whereas, production of lactic acid and ethanol were decreased, with the accumualation of 2,3-butanediol nearly unaltered. By fed-batch culture of the recombinant, the highest reported acetoin production level (25.9 g/L) by Klebsiella species was obtained. CONCLUSIONS The present study indicates that microbial production of acetoin could be improved by decreasing the intracellular NADH/NAD+ ratio in K. pneumoniae. It demonstrated that the cofactor engineering method, which is by manipulating the level of intracellular cofactors to redirect cellular metabolism, could be employed to achieve a high efficiency of producing the NAD+-dependent microbial metabolite.
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Affiliation(s)
- Xiao-Jun Ji
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing, 210009, People’s Republic of China
| | - Zhi-Fang Xia
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing, 210009, People’s Republic of China
| | - Ning-Hua Fu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing, 210009, People’s Republic of China
| | - Zhi-Kui Nie
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing, 210009, People’s Republic of China
| | - Meng-Qiu Shen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing, 210009, People’s Republic of China
| | - Qian-Qian Tian
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing, 210009, People’s Republic of China
| | - He Huang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing, 210009, People’s Republic of China
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Xiao Z, Wang X, Huang Y, Huo F, Zhu X, Xi L, Lu JR. Thermophilic fermentation of acetoin and 2,3-butanediol by a novel Geobacillus strain. BIOTECHNOLOGY FOR BIOFUELS 2012; 5:88. [PMID: 23217110 PMCID: PMC3538569 DOI: 10.1186/1754-6834-5-88] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Accepted: 11/30/2012] [Indexed: 05/04/2023]
Abstract
BACKGROUND Acetoin and 2,3-butanediol are two important biorefinery platform chemicals. They are currently fermented below 40°C using mesophilic strains, but the processes often suffer from bacterial contamination. RESULTS This work reports the isolation and identification of a novel aerobic Geobacillus strain XT15 capable of producing both of these chemicals under elevated temperatures, thus reducing the risk of bacterial contamination. The optimum growth temperature was found to be between 45 and 55°C and the medium initial pH to be 8.0. In addition to glucose, galactose, mannitol, arabionose, and xylose were all acceptable substrates, enabling the potential use of cellulosic biomass as the feedstock. XT15 preferred organic nitrogen sources including corn steep liquor powder, a cheap by-product from corn wet-milling. At 55°C, 7.7 g/L of acetoin and 14.5 g/L of 2,3-butanediol could be obtained using corn steep liquor powder as a nitrogen source. Thirteen volatile products from the cultivation broth of XT15 were identified by gas chromatography-mass spectrometry. Acetoin, 2,3-butanediol, and their derivatives including a novel metabolite 2,3-dihydroxy-3-methylheptan-4-one, accounted for a total of about 96% of all the volatile products. In contrast, organic acids and other products were minor by-products. α-Acetolactate decarboxylase and acetoin:2,6-dichlorophenolindophenol oxidoreductase in XT15, the two key enzymes in acetoin metabolic pathway, were found to be both moderately thermophilic with the identical optimum temperature of 45°C. CONCLUSIONS Geobacillus sp. XT15 is the first naturally occurring thermophile excreting acetoin and/or 2,3-butanediol. This work has demonstrated the attractive prospect of developing it as an industrial strain in the thermophilic fermentation of acetoin and 2,3-butanediol with improved anti-contamination performance. The novel metabolites and enzymes identified in XT15 also indicated its strong promise as a precious biological resource. Thermophilic fermentation also offers great prospect for improving its yields and efficiencies. This remains a core aim for future work.
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Affiliation(s)
- Zijun Xiao
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering & Biotechnology, China University of Petroleum, Qingdao, 266580, PR China
| | - Xiangming Wang
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering & Biotechnology, China University of Petroleum, Qingdao, 266580, PR China
| | - Yunling Huang
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering & Biotechnology, China University of Petroleum, Qingdao, 266580, PR China
| | - Fangfang Huo
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering & Biotechnology, China University of Petroleum, Qingdao, 266580, PR China
| | - Xiankun Zhu
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering & Biotechnology, China University of Petroleum, Qingdao, 266580, PR China
| | - Lijun Xi
- State Key Laboratory of Heavy Oil Processing and Centre for Bioengineering & Biotechnology, China University of Petroleum, Qingdao, 266580, PR China
| | - Jian R Lu
- Biological Physics Laboratory, School of Physics and Astronomy, University of Manchester, Manchester, M13 9PL, UK
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Shin HD, Yoon SH, Wu J, Rutter C, Kim SW, Chen RR. High-yield production of meso-2,3-butanediol from cellodextrin by engineered E. coli biocatalysts. BIORESOURCE TECHNOLOGY 2012; 118:367-73. [PMID: 22705958 DOI: 10.1016/j.biortech.2012.04.100] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Revised: 04/24/2012] [Accepted: 04/27/2012] [Indexed: 05/04/2023]
Abstract
Escherichia coli has been engineered to produce a variety of biofuel and biorefinery products. However, it can only produce these products from simple sugars, requiring large amounts of enzymes to depolymerize cellulose into monomer sugars. Engineering E. coli to directly use cellodextrin, the partial hydrolysis product of cellulose, potentially could reduce the requirement of enzyme thereby the overall cost. Through a combination of gene deletion, introduction of a synthetic operon, and periplasmic expression of a Saccharophagus cellodextrinase, we engineered, for the first time, an E. coli biocatalyst capable of producing BDO from cellodextrin. The success of the engineering strategy is evidenced by the high BDO yield (>80%) from cellodextrin. We additionally demonstrate that the engineered biocatalyst can be advantageously used in a SSF process for BDO production from cellulose as the expression of cellodextrinase from a BDO producer augments the insufficient β-glucosidase activities in a commercial cellulase cocktail.
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Affiliation(s)
- Hyun-Dong Shin
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
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Yong YC, Zhong JJ. Impacts of quorum sensing on microbial metabolism and human health. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2012; 131:25-61. [PMID: 22767136 DOI: 10.1007/10_2012_138] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Bacteria were considered to be lonely 'mutes' for hundreds of years. However, recently it was found that bacteria usually coordinate their behaviors at the population level by producing (speaking), sensing (listening), and responding to small signal molecules. This so-called quorum sensing (QS) regulation enables bacteria to live in a 'society' with cell-cell communication and controls many important bacterial behaviors. In this chapter, QS systems and their signal molecules for Gram-negative and Gram-positive bacteria are introduced. Most interestingly, QS regulates the important bacterial behaviors such as metabolism and pathogenesis. QS-regulated microbial metabolism includes antibiotic synthesis, pollutant biodegradation, and bioenergy production, which are very relevant to human health. QS is also well-known for its involvement in bacterial pathogenesis, such as iin nfections by Pseudomonas aeruginosa and Staphylococcus aureus. Novel disease diagnosis strategies and antimicrobial agents have also been developed based on QS regulation on bacterial infections. In addition, to meet the requirements for the detection/quantification of QS signaling molecules for research and application, different biosensors have been constructed, which will also be reviewed here. QS regulation is essential to bacterial survival and important to human health. A better understanding of QS could lead better control/manipulation of bacteria, thus making them more helpful to people.
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Affiliation(s)
- Yang-Chun Yong
- Biofuels Institute, School of the Environment, Jiangsu University, 301 Xuefu Road, 212013, Zhenjiang, Jiangsu Province, China
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Effantin G, Rivasseau C, Gromova M, Bligny R, Hugouvieux-Cotte-Pattat N. Massive production of butanediol during plant infection by phytopathogenic bacteria of the genera Dickeya and Pectobacterium. Mol Microbiol 2011; 82:988-97. [PMID: 22032684 DOI: 10.1111/j.1365-2958.2011.07881.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Plant pathogenic bacteria of the genera Dickeya and Pectobacterium are broad-host-range necrotrophs which cause soft-rot diseases in important crops. A metabolomic analysis, based on (13)C-NMR spectroscopy, was used to characterize the plant-bacteria interaction. Metabolic profiles revealed a decline in plant sugars and amino acids during infection and the concomitant appearance of a compound identified as 2,3-butanediol. Butanediol is the major metabolite found in macerated tissues of various host plants. It is accumulated during the symptomatic phase of the disease. Different species of Dickeya or Pectobacterium secrete high levels of butanediol during plant infection. Butanediol has been described as a signalling molecule involved in plant/bacterium interactions and, notably, able to induce plant systemic resistance. The bud genes, involved in butanediol production, are conserved in the phytopathogenic enterobacteria of the genera Dickeya, Pectobacterium, Erwinia, Pantoea and Brenneria. Inactivation of the bud genes of Dickeya dadantii revealed that the virulence of budA, budB and budR mutants was clearly reduced. The genes budA, budB and budC are highly expressed during plant infection. These data highlight the importance of butanediol metabolism in limiting acidification of the plant tissue during the development of the soft-rot disease caused by pectinolytic enterobacteria.
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Affiliation(s)
- Géraldine Effantin
- Université de Lyon, Université Lyon 1, INSA-Lyon, Microbiologie Adaptation et Pathogénie, CNRS UMR5240, Domaine Scientifique de la Doua, 69622 Villeurbanne, France
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Marquez-Villavicencio MDP, Weber B, Witherell RA, Willis DK, Charkowski AO. The 3-hydroxy-2-butanone pathway is required for Pectobacterium carotovorum pathogenesis. PLoS One 2011; 6:e22974. [PMID: 21876734 PMCID: PMC3158072 DOI: 10.1371/journal.pone.0022974] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 07/05/2011] [Indexed: 11/19/2022] Open
Abstract
Pectobacterium species are necrotrophic bacterial pathogens that cause soft rot diseases in potatoes and several other crops worldwide. Gene expression data identified Pectobacterium carotovorum subsp. carotovorum budB, which encodes the α-acetolactate synthase enzyme in the 2,3-butanediol pathway, as more highly expressed in potato tubers than potato stems. This pathway is of interest because volatiles produced by the 2,3-butanediol pathway have been shown to act as plant growth promoting molecules, insect attractants, and, in other bacterial species, affect virulence and fitness. Disruption of the 2,3-butanediol pathway reduced virulence of P. c. subsp. carotovorum WPP14 on potato tubers and impaired alkalinization of growth medium and potato tubers under anaerobic conditions. Alkalinization of the milieu via this pathway may aid in plant cell maceration since Pectobacterium pectate lyases are most active at alkaline pH.
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Affiliation(s)
| | - Brooke Weber
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - R. Andrews Witherell
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - David K. Willis
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Vegetable Crops Research Unit, Agricultural Research Service, United States Department of Agriculture, Madison, Wisconsin, United States of America
| | - Amy O. Charkowski
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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Ji XJ, Huang H, Ouyang PK. Microbial 2,3-butanediol production: a state-of-the-art review. Biotechnol Adv 2011; 29:351-64. [PMID: 21272631 DOI: 10.1016/j.biotechadv.2011.01.007] [Citation(s) in RCA: 430] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 01/07/2011] [Accepted: 01/19/2011] [Indexed: 12/01/2022]
Abstract
2,3-butanediol is a promising bulk chemical due to its extensive industry applications. The state-of-the-art nature of microbial 2,3-butanediol production is reviewed in this paper. Various strategies for efficient and economical microbial 2,3-butanediol production, including strain improvement, substrate alternation, and process development, are reviewed and compared with regard to their pros and cons. This review also summarizes value added derivatives of biologically produced 2,3-butanediol and different strategies for downstream processing. The future prospects of microbial 2,3-butanediol production are discussed in light of the current progress, challenges, and trends in this field. Guidelines for future studies are also proposed.
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Affiliation(s)
- Xiao-Jun Ji
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing 210009, People's Republic of China
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Singh V, Chandra D, Srivastava BS, Srivastava R. Biochemical and transcription analysis of acetohydroxyacid synthase isoforms in Mycobacterium tuberculosis identifies these enzymes as potential targets for drug development. Microbiology (Reading) 2011; 157:29-37. [DOI: 10.1099/mic.0.041343-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Acetohydroxyacid synthase (AHAS) is a biosynthetic enzyme essential for de novo synthesis of branched-chain amino acids. The genome sequence of Mycobacterium tuberculosis revealed genes encoding four catalytic subunits, ilvB1 (Rv3003c), ilvB2 (Rv3470c), ilvG (Rv1820) and ilvX (Rv3509c), and one regulatory subunit, ilvN (Rv3002c), of AHAS. All these genes were found to be expressed in M. tuberculosis growing in vitro. Each AHAS subunit gene was cloned and expressed in Escherichia coli. AHAS activity of IlvB1 and IlvG was found in cell-free lysates and with recombinant purified proteins. Kinetic studies with purified IlvG revealed positive cooperativity towards substrate and cofactors. To understand the role of the catalytic subunits in the biology of M. tuberculosis, expression of AHAS genes was analysed in different physiological conditions. ilvB1, ilvB2 and ilvG were differentially expressed. The role of ilvB1 in persistence is known, but the upregulation of ilvB2 and ilvG in extended stationary phase, ex vivo, and in acid stress and hypoxic environments, suggests the relevance of AHAS enzymes in the metabolism and survival of M. tuberculosis by functioning as catabolic AHAS. These enzymes are therefore potential targets for drug development.
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Affiliation(s)
- Vinayak Singh
- Microbiology Division, Central Drug Research Institute, CSIR, Lucknow 226001, India
| | - Deepak Chandra
- Department of Biochemistry, University of Lucknow, Lucknow 226001, India
| | - Brahm S. Srivastava
- Microbiology Division, Central Drug Research Institute, CSIR, Lucknow 226001, India
| | - Ranjana Srivastava
- Microbiology Division, Central Drug Research Institute, CSIR, Lucknow 226001, India
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Abstract
Microbial production of 2,3-butanediol by Klebsiella oxytoca occurs under conditions of an oxygen limitation. The extent to which substrate is oxidized to 2,3-butanediol and its coproducts, (acetic acid, acetoin, and ethanol) and the relative flow rates of substrate to energetic and biosynthetic pathways are controlled by the degree of oxygen limitation. Two energetic relationships which describe the response to an oxygen limitation have been derived. The first relationship describes the coupling between growth and energy production observed under oxygen-limited conditions. This allows calculation of energetic parameters and modeling of the cell mass and substrate profiles in terms of the degree of oxygen limitation only. The second relationship describes the average degree of oxidation and the rate of the end-product flow. The model has been tested with both batch and continuous culture. During these kinetic studies, two phases of growth have been observed: energy-coupled growth, which was described above; and, energy-uncoupled growth, which arises when the degree of oxygen limitation reaches a critical value. Optimal culture performance with respect to 2,3-butanediol productivity occurs during energy-coupled growth.
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Affiliation(s)
- P B Beronio
- Amoco Oil Company, Amoco Research Center, Naperville, Illinois, USA
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Zhu BF, Xu Y, Fan WL. High-yield fermentative preparation of tetramethylpyrazine by Bacillus sp. using an endogenous precursor approach. J Ind Microbiol Biotechnol 2009; 37:179-86. [DOI: 10.1007/s10295-009-0661-5] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2009] [Accepted: 10/23/2009] [Indexed: 11/30/2022]
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Engineering Klebsiella oxytoca for efficient 2, 3-butanediol production through insertional inactivation of acetaldehyde dehydrogenase gene. Appl Microbiol Biotechnol 2009; 85:1751-8. [DOI: 10.1007/s00253-009-2222-2] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2009] [Revised: 08/25/2009] [Accepted: 08/25/2009] [Indexed: 10/20/2022]
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Olsen MJ, Pérez-Díaz IM. Influence of microbial growth on the redox potential of fermented cucumbers. J Food Sci 2009; 74:M149-53. [PMID: 19490331 DOI: 10.1111/j.1750-3841.2009.01121.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Commonly, pH measurements are used during the production of fermented cucumbers to indirectly monitor growth of lactic acid bacteria (LAB) and acid production. Redox potential (E(h)) measurements, which are determined by the potential of an electron to reduce an acceptor, could serve as an alternative tool to monitor the progress of fermentation allowing the detection of the metabolic activity and/or growth of LAB and other microorganisms. Pasteurized and inoculated jars of cucumbers were observed to better understand how the E(h) changes during the cucumber fermentation and how it could be used as a monitoring tool. Jars of diced, brined cucumbers were pasteurized and inoculated with microbes previously isolated from fermented cucumbers including Lactobacillus plantarum, Zygosaccharomyces globiformis, and Enterobacter aerogenes. Although an initial decrease in E(h) was observed for all microorganisms, distinctive trends in E(h) occurred when these organisms were inoculated. After a 2-wk fermentation period, the E(h) (Ag/AgCl, 3 M KCl) in jars inoculated with L. plantarum, Z. globiformis, and E. aerogenes was at +453 +/- 55, +104 +/- 5, and -156 +/- 73 mV, respectively. Cucumbers inoculated with a mixture of L. plantarum and Z. globiformis had a terminal E(h) value of +202 +/- 24 mV, which was between that found for the individual microorganisms. L. plantarum dominated the E(h) trend when inoculated along with E. aerogenes with a final E(h) of +411 +/- 72 mV. The results showed that changes in E(h) continued after pH measurements became stable. Thus E(h) measurement can provide a tool to continuously monitor microbial growth during the course of cucumber fermentations.
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Affiliation(s)
- Maegan J Olsen
- Dept. of Food, Bioprocessing and Nutrition Sciences, North Carolina State Univ., Raleigh, NC 27698-7624, USA
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Barriuso-Iglesias M, Schluesener D, Barreiro C, Poetsch A, Martín JF. Response of the cytoplasmic and membrane proteome of Corynebacterium glutamicum ATCC 13032 to pH changes. BMC Microbiol 2008; 8:225. [PMID: 19091079 PMCID: PMC2627906 DOI: 10.1186/1471-2180-8-225] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2008] [Accepted: 12/17/2008] [Indexed: 11/10/2022] Open
Abstract
Background C. glutamicum has traditionally been grown in neutral-pH media for amino acid production, but in a previous article we reported that this microorganism is a moderate alkaliphile since it grows optimally at pH 7.0–9.0, as shown in fermentor studies under tightly controlled pH conditions. We determined the best pH values to study differential expression of several genes after acidic or basic pH conditions (pH 6.0 for acidic expression and pH 9.0 for alkaline expression). Thus, it was interesting to perform a detailed analysis of the pH-adaptation response of the proteome of C. glutamicum ATCC 13032 to clarify the circuits involved in stress responses in this bacterium. In this paper we used the above indicated pH conditions, based on transcriptional studies, to confirm that pH adaptation results in significant changes in cytoplasmatic and membrane proteins. Results The cytoplasmatic and membrane proteome of Corynebacterium glutamicum ATCC 13032 at different pH conditions (6.0, 7.0 and 9.0) was analyzed by classical 2D-electrophoresis, and by anion exchange chromatography followed by SDS-PAGE (AIEC/SDS-PAGE). A few cytoplasmatic proteins showed differential expression at the three pH values with the classical 2D-technique including a hypothetical protein cg2797, L-2.3-butanediol dehydrogenase (ButA), and catalase (KatA). The AIEC/SDS-PAGE technique revealed several membrane proteins that respond to pH changes, including the succinate dehydrogenase complex (SdhABCD), F0F1-ATP synthase complex subunits b, α and δ (AtpF, AtpH and AtpA), the nitrate reductase II α subunit (NarG), and a hypothetical secreted/membrane protein cg0752. Induction of the F0F1-ATP synthase complex β subunit (AtpD) at pH 9.0 was evidenced by Western analysis. By contrast, L-2.3-butanediol dehydrogenase (ButA), an ATPase with chaperone activity, the ATP-binding subunit (ClpC) of an ATP-dependent protease complex, a 7 TMHs hypothetical protein cg0896, a conserved hypothetical protein cg1556, and the dihydrolipoamide acyltransferase SucB, were clearly up-regulated at pH 6.0. Conclusion The observed protein changes explain the effect of the extracellular pH on the growth and physiology of C. glutamicum. Some of the proteins up-regulated at alkaline pH respond also to other stress factors suggesting that they serve to integrate the cell response to different stressing conditions.
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Affiliation(s)
- Mónica Barriuso-Iglesias
- Instituto de Biotecnología de León (INBIOTEC), Parque Científico de León, Av. Real, 1, 24006. León, Spain.
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Hakalehto E, Humppi T, Paakkanen H. Dualistic acidic and neutral glucose fermentation balance in small intestine: Simulation in vitro. PATHOPHYSIOLOGY 2008; 15:211-20. [DOI: 10.1016/j.pathophys.2008.07.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2008] [Revised: 07/19/2008] [Accepted: 07/20/2008] [Indexed: 10/21/2022] Open
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Lovitt RW, Kim BH, Shen GJ, Zeikus JG, Phillips JA. Solvent Production by Microorganisms. Crit Rev Biotechnol 2008. [DOI: 10.3109/07388558809150725] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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40
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Dainty R, Hofman F. The influence of glucose concentration and culture incubation time on end-product formation during aerobic growth ofBrochothrix thermosphacta. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1365-2672.1983.tb01320.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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41
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Ragout A, Siñeriz F, Diekmann H, de Valdez GF. Effect of environmental pH on the fermentation balance of Lactobacillus reuteri. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1365-2672.1994.tb03439.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Menéndez A, Fernández L, Reimundo P, Guijarro JA. Genes required for Lactococcus garvieae survival in a fish host. MICROBIOLOGY-SGM 2007; 153:3286-3294. [PMID: 17906128 DOI: 10.1099/mic.0.2007/007609-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Lactococcus garvieae is considered an emergent pathogen in aquaculture and it is also associated with mastitis in domestic animals as well as human endocarditis and septicaemia. In spite of this, the pathogenic mechanisms of this bacterium are poorly understood. Signature-tagged mutagenesis was used to identify virulence factors and to establish the basis of pathogen-host interactions. A library of 1250 L. garvieae UNIUD074-tagged Tn917 mutants in 25 pools was screened for the ability to grow in fish. Among them, 29 mutants (approx. 2.4 %) were identified which could not be recovered from rainbow trout following infection. Sequence analysis of the tagged Tn917-interrupted genes in these mutants indicated the participation in pathogenesis of the transcriptional regulatory proteins homologous to GidA and MerR; the metabolic enzymes asparagine synthetase A and alpha-acetolactate synthase; the ABC transport system of glutamine and a calcium-transporting ATPase; the dltA locus involved in alanylation of teichoic acids; and hypothetical proteins containing EAL and Eis domains, among others. Competence index experiments in several of the selected mutants confirmed the relevance of the Tn917-interrupted genes in the development of the infection process. The results suggested some of the metabolic routes and enzymic systems necessary for the complete virulence of this bacterium. This work is believed to represent the first report of a genome-wide scan for virulence factors in L. garvieae. The identified genes will further our understanding of the pathogenesis of L. garvieae infections and may provide targets for intervention or lead to the development of novel therapies.
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Affiliation(s)
- Aurora Menéndez
- Área de Microbiología, Departamento de Biología Funcional, Facultad de Medicina, IUBA, Universidad de Oviedo, 33006 Oviedo, Asturias, Spain
| | - Lucia Fernández
- Área de Microbiología, Departamento de Biología Funcional, Facultad de Medicina, IUBA, Universidad de Oviedo, 33006 Oviedo, Asturias, Spain
| | - Pilar Reimundo
- Área de Microbiología, Departamento de Biología Funcional, Facultad de Medicina, IUBA, Universidad de Oviedo, 33006 Oviedo, Asturias, Spain
| | - José A Guijarro
- Área de Microbiología, Departamento de Biología Funcional, Facultad de Medicina, IUBA, Universidad de Oviedo, 33006 Oviedo, Asturias, Spain
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Abstract
Acetoin is an important physiological metabolite excreted by many microorganisms. The excretion of acetoin, which can be diagnosed by the Voges Proskauer test and serves as a microbial classification marker, has its vital physiological meanings to these microbes mainly including avoiding acification, participating in the regulation of NAD/NADH ratio, and storaging carbon. The well-known anabolism of acetoin involves alpha-acetolactat synthase and alpha-acetolactate decarboxylase; yet its catabolism still contains some differing views, although much attention has been focused on it and great advances have been achieved. Current findings in catabolite control protein A (CcpA) mediated carbon catabolite repression may provide a fuller understanding of the control mechanism in bacteria. In this review, we first examine the acetoin synthesis pathways and its physiological meanings and relevancies; then we discuss the relationship between the two conflicting acetoin cleavage pathways, the enzymes of the acetoin dehydrogenase enzyme system, major genes involved in acetoin degradation, and the CcpA mediated acetoin catabolite repression pathway; in the end we discuss the genetic engineering progresses concerning applications. To date, this is the first integrated review on acetoin metabolism in bacteria, especially with regard to catabolic aspects. The apperception of the generation and dissimilation of acetoin in bacteria will help provide a better understanding of microbial strategies in the struggle for resources, which will consequently better serve the utilization of these microbes.
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Affiliation(s)
- Zijun Xiao
- State Key Laboratory of Microbial Technology, Shandong University, People's Republic of China
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Abstract
Many bacteria use cell-cell communication to monitor their population density, synchronize their behaviour and socially interact. This communication results in a coordinated gene regulation and is generally called quorum sensing. In gram-negative bacteria, the most common quorum signal molecules are acylated homoserine lactones (AHLs), although other low-molecular-mass signalling molecules have been described such as Autoinducer-2 (AI-2). The phenotypes that are regulated in Serratia species by means of AHLs are remarkably diverse and of profound biological and ecological significance, and often interconnected with other global regulators. Furthermore, AHL- and AI-2-mediated systems (less profoundly studied) are continuously being discovered and explored in Serratia spp., many having interesting twists on the basic theme. Therefore, this review will highlight the current known quorum sensing systems in Serratia spp., including the important nosocomial pathogen Serratia marcescens.
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Affiliation(s)
- Rob Van Houdt
- Molecular and Cellular Biology, Institute for Health, Environment and Safety, Belgian Nuclear Research Centre SCK x CEN, Mol, Belgium.
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Van Houdt R, Aertsen A, Michiels CW. Quorum-sensing-dependent switch to butanediol fermentation prevents lethal medium acidification in Aeromonas hydrophila AH-1N. Res Microbiol 2007; 158:379-85. [PMID: 17408926 DOI: 10.1016/j.resmic.2006.11.015] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2006] [Revised: 11/28/2006] [Accepted: 11/28/2006] [Indexed: 11/19/2022]
Abstract
Aeromonas hydrophila AH-1N shows biphasic growth in glucose containing broth at 30 degrees C. The first phase is characterized by strong acidification, while the second phase is accompanied by an increase in medium pH. Disruption of AHL production by knockout of ahyI did not affect the first growth phase, but resulted in further acidification which completely blocked the second growth phase and even caused cell death. The block could be relieved by addition of 5 microM (or less) synthetic N-butanoyl-L-homoserine lactone (C4-HSL), the major AHL produced by A. hydrophila AH-1N. Further analysis revealed that, as shown previously for Serratia plymuthica, butanediol fermentation is regulated by AHL-mediated quorum sensing in A. hydrophila AH-1N. These results indicate that A. hydrophila switches to butanediol fermentation to reduce medium acidification under certain conditions and to allow further growth if nutrient resources are not yet exhausted.
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Affiliation(s)
- Rob Van Houdt
- Center for Food and Microbial Technology, Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering, Katholieke Universiteit Leuven, Kasteelpark Arenberg 22, B-3001 Leuven, Belgium
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Yoon SS, Mekalanos JJ. 2,3-butanediol synthesis and the emergence of the Vibrio cholerae El Tor biotype. Infect Immun 2006; 74:6547-56. [PMID: 17015461 PMCID: PMC1698044 DOI: 10.1128/iai.00695-06] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Vibrio cholerae is an aquatic bacterium that causes the severe diarrheal disease cholera. V. cholerae strains of the O1 serogroup exist as two biotypes, classical and El Tor. Toxigenic strains of the El Tor biotype emerged to cause the seventh pandemic of cholera in 1961 and subsequently displaced strains of the classical biotype both in the environment and as a cause of cholera within a decade. The factors that drove emergence of the El Tor biotype and the displacement of the classical biotype are unknown. Here, we show a unique difference in carbohydrate metabolism between these two biotypes. When grown with added carbohydrates, classical biotype strains generated a sharp decrease in medium pH, resulting in loss of viability. However, growth of El Tor biotype strain N16961 was enhanced due to its ability to produce 2,3-butanediol, a neutral fermentation end product, and suppress the accumulation of organic acids. An N16961 mutant (SSY01) defective in 2,3-butanediol synthesis showed the same defect in growth that classical biotype strains show in media rich in carbohydrates. Importantly, the SSY01 mutant was attenuated in its ability to colonize the intestines of infant mice, suggesting that host carbohydrates may be available to V. cholerae within the intestinal environment. Similarly, the SSY01 mutant failed to develop biofilms when utilizing N-acetyl-D-glucosamine as a carbon source. Because growth on N-acetyl-D-glucosamine likely reflects the ability of a strain to grow on chitin in certain aquatic environments, we conclude that the strains of classical biotype are likely defective compared to those of El Tor in growth in any environmental niche that is rich in chitin and/or other metabolizable carbohydrates. We propose that the ability to metabolize sugars without production of acid by-products might account for the improved evolutionary fitness of the V. cholerae El Tor biotype compared to that of the classical biotype both as a global cause of cholera and as an environmental organism.
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Affiliation(s)
- Sang Sun Yoon
- Department of Microbiology and Molecular Genetics, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA
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Van Houdt R, Moons P, Hueso Buj M, Michiels CW. N-acyl-L-homoserine lactone quorum sensing controls butanediol fermentation in Serratia plymuthica RVH1 and Serratia marcescens MG1. J Bacteriol 2006; 188:4570-2. [PMID: 16740963 PMCID: PMC1482955 DOI: 10.1128/jb.00144-06] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Butanediol fermentation in two Serratia species is shown to be affected by N-acyl-L-homoserine lactone-dependent quorum sensing. Knockout of quorum-sensing signal production caused a shift towards enhanced acid production, resulting in early growth arrest, which was reversible by the addition of synthetic signal molecules.
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Affiliation(s)
- Rob Van Houdt
- Centre for Food and Microbial Technology, Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering, Katholieke Universiteit Leuven, Leuven, Belgium
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Jansen NB, Tsao GT. Bioconversion of pentoses to 2,3-butanediol by Klebsiella pneumoniae. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2005; 27:85-99. [PMID: 6437156 DOI: 10.1007/bfb0009105] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Ito T, Nakashimada Y, Kakizono T, Nishio N. High-yield production of hydrogen by Enterobacter aerogenes mutants with decreased alpha-acetolactate synthase activity. J Biosci Bioeng 2005; 97:227-32. [PMID: 16233620 DOI: 10.1016/s1389-1723(04)70196-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2003] [Accepted: 01/10/2004] [Indexed: 11/26/2022]
Abstract
To enhance hydrogen (H2) production from glucose by Enterobacter aerogenes HU-101, two mutants, strains VP-1 and VP-2, with decreased alpha-acetolactate synthase activity, were isolated using the Voges-Proskauer (VP) test. In pH-uncontrolled batch culture, both mutants showed a lower 2,3-butanediol yield for the glucose consumed than that shown by the wild-type strain, although glucose remained in the medium after 12 h of culture. In the same cultures, compared to the H2 yield of 0.80 mol/mol-glucose of the wild-type strain, strain VP-1 showed a high H2 yield of 1.8 mol/mol-glucose with decreased lactate and increased succinate yields, while strain VP-2 showed an H2 yield of 1.0 mol/mol-glucose with an increased lactate yield. Increasing the phosphate buffer concentration, which contributes to maintaining the pH in the medium, increased the glucose consumption by both strains. However, in a pH-controlled batch culture at neutral pH, the H2 yield of strain VP-1 was decreased to 1.2 mol/mol-glucose due to the accumulation of formate, an intermediate of the H2-producing pathway, with the yield of H2 plus formate being 1.7 mol/mol-glucose.
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Affiliation(s)
- Takeshi Ito
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8530, Japan
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Kovacikova G, Lin W, Skorupski K. Dual regulation of genes involved in acetoin biosynthesis and motility/biofilm formation by the virulence activator AphA and the acetate-responsive LysR-type regulator AlsR inVibrio cholerae. Mol Microbiol 2005; 57:420-33. [PMID: 15978075 DOI: 10.1111/j.1365-2958.2005.04700.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AphA is a quorum sensing-regulated activator that initiates the virulence cascade in Vibrio cholerae by cooperating with the LysR-type regulator AphB at the tcpPH promoter on the Vibrio pathogenicity island (VPI). To identify the ancestral chromosomal genes in V. cholerae regulated by AphA, we carried out a microarray analysis and show here that AphA influences the expression of 15 genes not associated with the VPI. One set of genes strongly repressed by AphA is involved in the biosynthesis of acetoin, a product synthesized by a variety of bacteria that plays a role in preventing intracellular acidification and which is essential for the viability of V. cholerae in the presence of glucose. Also present in this operon are two putative signal transduction proteins with EAL and GGDEF domains that oppositely influence motility and biofilm formation. Gel mobility shift assays show that AphA binds to a site upstream of the first gene in the acetoin operon. Transcriptional lacZ fusions indicate that at low cell density AphA represses the expression of the acetoin genes up to 15-fold. Voges Proskauer tests confirm that deletion of AphA increases the production of acetoin under non-inducing conditions and also that the LysR-type regulator AlsR divergently transcribed from the operon is required for its production. This is the first report of a specific repressor protein involved in the transcriptional control of acetoin production as well as the co-regulation of these genes with those that influence motility and biofilm formation. The results here provide a model for the dual regulation of these processes by acetate and quorum sensing through AlsR and AphA.
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Affiliation(s)
- Gabriela Kovacikova
- Department of Microbiology and Immunology, Dartmouth Medical School, Hanover, NH 03755, USA
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