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Kim GY, Yang J, Han YH, Seo SW. Synthetic redesign of Escherichia coli W for faster metabolism of sugarcane molasses. Microb Cell Fact 2024; 23:242. [PMID: 39252026 PMCID: PMC11382391 DOI: 10.1186/s12934-024-02520-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2024] [Accepted: 09/02/2024] [Indexed: 09/11/2024] Open
Abstract
BACKGROUND Sugarcane molasses, rich in sucrose, glucose, and fructose, offers a promising carbon source for industrial fermentation due to its abundance and low cost. However, challenges arise from the simultaneous utilization of multiple sugars and carbon catabolite repression (CCR). Despite its nutritional content, sucrose metabolism in Escherichia coli, except for W strain, remains poorly understood, hindering its use in microbial fermentation. In this study, E. coli W was engineered to enhance sugar consumption rates and overcome CCR. This was achieved through the integration of a synthetically designed csc operon and the optimization of glucose and fructose co-utilization pathways. These advancements facilitate efficient utilization of sugarcane molasses for the production of 3-hydroxypropionic acid (3-HP), contributing to sustainable biochemical production processes. RESULTS In this study, we addressed challenges associated with sugar metabolism in E. coli W, focusing on enhancing sucrose consumption and improving glucose-fructose co-utilization. Through targeted engineering of the sucrose utilization system, we achieved accelerated sucrose consumption rates by modulating the expression of the csc operon components, cscB, cscK, cscA, and cscR. Our findings revealed that monocistronic expression of the csc genes with the deletion of cscR, led to optimal sucrose utilization without significant growth burden. Furthermore, we successfully alleviated fructose catabolite repression by modulating the binding dynamics of FruR with the fructose PTS regulon, enabling near-equivalent co-utilization of glucose and fructose. To validate the industrial applicability of our engineered strain, we pursued 3-HP production from sugarcane molasses. By integrating heterologous genes and optimizing metabolic pathways, we achieved improvements in 3-HP titers compared to previous studies. Additionally, glyceraldehyde-3-phosphate dehydrogenase (gapA) repression aids in carbon flux redistribution, enhancing molasses conversion to 3-HP. CONCLUSIONS Despite limitations in sucrose metabolism, the redesigned E. coli W strain, adept at utilizing sugarcane molasses, is a valuable asset for industrial fermentation. Its synthetic csc operon enhances sucrose consumption, while mitigating CCR improves glucose-fructose co-utilization. These enhancements, coupled with repression of gapA, aim to efficiently convert sugarcane molasses into 3-HP, addressing limitations in sucrose and fructose metabolism for industrial applications.
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Affiliation(s)
- Gi Yeon Kim
- Interdisciplinary Program in Bioengineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Jina Yang
- Department of Chemical Engineering, Jeju National University, 102, Jejudaehak-ro, Jeju-si, Jeju-do, 63243, Korea
| | - Yong Hee Han
- Interdisciplinary Program in Bioengineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
- School of Biological Sciences and Biotechnology, Graduate School, and School of Biological Sciences and Technology, Chonnam National University, Yongbong-ro 77, Gwangju, 61186, South Korea
| | - Sang Woo Seo
- Interdisciplinary Program in Bioengineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
- School of Chemical and Biological Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
- Institute of Chemical Processes, and Bio-MAX Institute, and Institute of Bio Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
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Hriňová K, Dlapová J, Kubala B, Kormanová Ľ, Levarski Z, Struhárňanská E, Turňa J, Stuchlík S. Production of Reverse Transcriptase and DNA Polymerase in Bacterial Expression Systems. Bioengineering (Basel) 2024; 11:727. [PMID: 39061809 PMCID: PMC11274053 DOI: 10.3390/bioengineering11070727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2024] [Revised: 07/10/2024] [Accepted: 07/16/2024] [Indexed: 07/28/2024] Open
Abstract
DNA amplification and reverse transcription enzymes have proven to be invaluable in fast and reliable diagnostics and research applications because of their processivity, specificity, and robustness. Our study focused on the production of mutant Taq DNA polymerase and mutant M-MLV reverse transcriptase in the expression hosts Vibrio natriegens and Escherichia coli under various expression conditions. We also examined nonspecific extracellular production in V. natriegens. Intracellularly, M-MLV was produced in V. natriegens at the level of 11% of the total cell proteins (TCPs) compared with 16% of TCPs in E. coli. We obtained a soluble protein that accounted for 11% of the enzyme produced in V. natriegens and 22% of the enzyme produced in E. coli. Taq pol was produced intracellularly in V. natriegens at the level of 30% of TCPs compared with 26% of TCPs in E. coli. However, Taq pol was almost non-soluble in E. coli, whereas in V. natriegens, we obtained a soluble protein that accounted for 23% of the produced enzyme. We detected substantial extracellular production of Taq pol. Thus, V. natriegens is a suitable alternative host with the potential for production of recombinant proteins.
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Affiliation(s)
- Kristína Hriňová
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University in Bratislava, 84215 Bratislava, Slovakia; (K.H.); (J.D.); (Ľ.K.); (E.S.); (J.T.); (S.S.)
| | - Johana Dlapová
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University in Bratislava, 84215 Bratislava, Slovakia; (K.H.); (J.D.); (Ľ.K.); (E.S.); (J.T.); (S.S.)
| | - Bohuš Kubala
- Laboratory for Microbial Ecology, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská Cesta 21, 84551 Bratislava, Slovakia;
| | - Ľubica Kormanová
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University in Bratislava, 84215 Bratislava, Slovakia; (K.H.); (J.D.); (Ľ.K.); (E.S.); (J.T.); (S.S.)
| | - Zdenko Levarski
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University in Bratislava, 84215 Bratislava, Slovakia; (K.H.); (J.D.); (Ľ.K.); (E.S.); (J.T.); (S.S.)
- Science Park, Comenius University in Bratislava, 84104 Bratislava, Slovakia
- ReKoMBe, s.r.o., 84102 Bratislava, Slovakia
| | - Eva Struhárňanská
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University in Bratislava, 84215 Bratislava, Slovakia; (K.H.); (J.D.); (Ľ.K.); (E.S.); (J.T.); (S.S.)
- ReKoMBe, s.r.o., 84102 Bratislava, Slovakia
| | - Ján Turňa
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University in Bratislava, 84215 Bratislava, Slovakia; (K.H.); (J.D.); (Ľ.K.); (E.S.); (J.T.); (S.S.)
- Science Park, Comenius University in Bratislava, 84104 Bratislava, Slovakia
- ReKoMBe, s.r.o., 84102 Bratislava, Slovakia
| | - Stanislav Stuchlík
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University in Bratislava, 84215 Bratislava, Slovakia; (K.H.); (J.D.); (Ľ.K.); (E.S.); (J.T.); (S.S.)
- Science Park, Comenius University in Bratislava, 84104 Bratislava, Slovakia
- ReKoMBe, s.r.o., 84102 Bratislava, Slovakia
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3
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Stephens C, Martinez M, Leonardi V, Jaing J, Miller A. The Scr and Csc pathways for sucrose utilization co-exist in E. coli, but only the Scr pathway is widespread in other Enterobacteriaceae. Front Microbiol 2024; 15:1409295. [PMID: 39021635 PMCID: PMC11251922 DOI: 10.3389/fmicb.2024.1409295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Accepted: 06/17/2024] [Indexed: 07/20/2024] Open
Abstract
Most Escherichia coli isolates from humans do not utilize D-sucrose as a substrate for fermentation or growth. Previous work has shown that the Csc pathway allows some E. coli to utilize sucrose for slow growth, and this pathway has been engineered in E. coli W strains to enhance use of sucrose as a feedstock for industrial applications. An alternative sucrose utilization pathway, Scr, was first identified in Klebsiella pneumoniae and has been reported in some E. coli and Salmonella enterica isolates. We show here that the Scr pathway is native to an important subset of E. coli phylogroup B2 lineages that lack the Csc pathway but grow rapidly on sucrose. Laboratory E. coli strains derived from MG1655 (phylogroup A, ST10) are unable to utilize sucrose and lack the scr and csc genes, but a recombinant plasmid-borne scr locus enables rapid growth on and fermentation of sucrose. Genome analyses of Enterobacteriaceae indicate that the scr locus is widespread in other Enterobacteriaceae; including Enterobacter and Klebsiella species, and some Citrobacter and Proteus species. In contrast, the Csc pathway is limited mostly to E. coli, some Shigella species (in which csc loci are rendered non-functional by various mutations), and Citrobacter freundii. The more efficient Scr pathway likely has greater potential than the Csc pathway for bioindustrial applications of E. coli and other Enterobacteriaceae using sucrose as a feedstock.
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Affiliation(s)
- Craig Stephens
- Department of Biology, Santa Clara University, Santa Clara, CA, United States
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Lin NQ, Liang ZB, Wang HS, Wu XY, Zhang LH, Deng YZ. Engineered Sucrose Metabolism Improves the Smut Disease Suppression Potency of Pseudomonas sp. ST4. Appl Environ Microbiol 2023; 89:e0220822. [PMID: 37093016 PMCID: PMC10231245 DOI: 10.1128/aem.02208-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 04/03/2023] [Indexed: 04/25/2023] Open
Abstract
Sporisorium scitamineum and Ustilago maydis are two fungal pathogens causing severe sugarcane and maize diseases, respectively. Sexual mating of compatible sporidia is essential for these pathogens to form infections dikaryotic mycelia and cause smut diseases. We showed recently that in the presence of exogenous glucose, the Pseudomonas sp. strain ST4 could block the fungal mating and display a strong disease suppression potency on S. scitamineum. With the aim of conferring strain ST4 the ability to metabolize sucrose in plants for glucose production, we identified a strong native promoter pSsrA in strain ST4 and additional promoter elements to facilitate translation and peptide translocation for the construction of a fusion gene encoding sucrose metabolism. The cscA gene encoding sucrose hydrolase from Pseudomonas protegens Pf-5 was fused to the promoter pSsrA, a translational coupler bicistronic design and a Tat signal peptide, which was then cloned into mini-Tn7 transposon. This synthetic gene cassette was integrated into the chromosome of strain ST4, and the resultant engineered strain ST4E was able to hydrolyze sucrose with high efficiency and displayed elevated inhibitory activity on the mating and virulence of S. scitamineum and U. maydis. The findings from this study provide a valuable device and useful clues for the engineering of sucrose metabolism in non- or weak-sucrose-utilizing bacterial strains and present an improved biocontrol agent against plant smut pathogens. IMPORTANCE Sporisorium scitamineum and Ustilago maydis are typical dimorphic fungi causing severe sugarcane and maize smut diseases, respectively. Sexual mating of compatible sporidia is essential for these pathogens to form infections dikaryotic mycelia and cause smut diseases. We previously demonstrated that the biocontrol strain Pseudomonas sp. ST4 could block the fungal mating and displays a strong suppression potency on smut diseases, while it was unable to utilize the host-sourced sucrose for glucose production critical for antifungus efficiency. In this study, we constructed a high-expression gene cassette for minitransposon-mediated genome integration and sucrose hydrolysis in the bacterial periplasmic space. The resultant engineered strain ST4E was able to hydrolyze sucrose and inhibit the mating and hyphal growth of S. scitamineum and U. maydis. These findings provide a valuable tool and useful clues for the engineering of sucrose metabolism in non- or weak-sucrose-utilizing bacterial strains and present an improved biocontrol agent against plant smut pathogens.
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Affiliation(s)
- Nuo Qiao Lin
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, China
| | - Zhi Bin Liang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, China
| | - Hui Shan Wang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, China
| | - Xiao Yan Wu
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, China
| | - Lian Hui Zhang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, China
| | - Yi Zhen Deng
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, China
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5
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Ni D, Chen Z, Tian Y, Xu W, Zhang W, Kim BG, Mu W. Comprehensive utilization of sucrose resources via chemical and biotechnological processes: A review. Biotechnol Adv 2022; 60:107990. [PMID: 35640819 DOI: 10.1016/j.biotechadv.2022.107990] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/20/2022] [Accepted: 05/24/2022] [Indexed: 11/30/2022]
Abstract
Sucrose, one of the most widespread disaccharides in nature, has been available in daily human life for many centuries. As an abundant and cheap sweetener, sucrose plays an essential role in our diet and the food industry. However, it has been determined that many diseases, such as obesity, diabetes, hyperlipidemia, etc., directly relate to the overconsumption of sucrose. It arouses many explorations for the conversion of sucrose to high-value chemicals. Production of valuable substances from sucrose by chemical methods has been studied since a half-century ago. Compared to chemical processes, biotechnological conversion approaches of sucrose are more environmentally friendly. Many enzymes can use sucrose as the substrate to generate functional sugars, especially those from GH68, GH70, GH13, and GH32 families. In this review, enzymatic catalysis and whole-cell fermentation of sucrose for the production of valuable chemicals were reviewed. The multienzyme cascade catalysis and metabolic engineering strategies were addressed.
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Affiliation(s)
- Dawei Ni
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Ziwei Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Yuqing Tian
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wei Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Byung-Gee Kim
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, Jiangsu 214122, China.
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6
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Carruthers DN, Saleski TE, Scholz SA, Lin XN. Random Chromosomal Integration and Screening Yields E. coli K-12 Derivatives Capable of Efficient Sucrose Utilization. ACS Synth Biol 2020; 9:3311-3321. [PMID: 33236893 DOI: 10.1021/acssynbio.0c00392] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Chromosomal expression of heterologous genes offers stability and maintenance advantages over episomal expression, yet remains difficult to optimize through site-specific integration. The challenge has in large part been due to the variability of chromosomal gene expression, which has only recently been shown to be affected by multiple factors, including the local genomic context. In this work we utilize Tn5 transposase to randomly integrate a three-gene csc operon encoding nonphosphotransferase sucrose catabolism into the E. coli K-12 chromosome. Isolates from the transposon library yielded a range of growth rates on sucrose as the sole carbon source, including some that were comparable to that of E. coli K-12 on glucose (μmax = 0.70 ± 0.03 h-1). Narrowness of the growth rate distributions and faster growth compared to plasmids indicate that efficient csc expression is attainable. Furthermore, enhanced growth rate upon transduction into strains that underwent adaptive laboratory evolution indicate that sucrose catabolism is not limiting to cellular growth. We also show that transduction of a csc fast-growth locus into an isobutanol production strain yields high titer (7.56 ± 0.25 g/L) on sucrose as the sole carbon source. Our results demonstrate that random integration is an effective strategy for optimizing heterologous expression within the context of cellular metabolism for both fast growth and biochemical production phenotypes.
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Affiliation(s)
- David N. Carruthers
- Chemical Engineering Department, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Tatyana E. Saleski
- Chemical Engineering Department, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Scott A. Scholz
- Department of Biochemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Xiaoxia Nina Lin
- Chemical Engineering Department, University of Michigan, Ann Arbor, Michigan 48109, United States
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Chen LZ, Huang SL, Hou J, Guo XP, Wang FS, Sheng JZ. Cell-based and cell-free biocatalysis for the production of D-glucaric acid. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:203. [PMID: 33303009 PMCID: PMC7731778 DOI: 10.1186/s13068-020-01847-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 12/02/2020] [Indexed: 05/17/2023]
Abstract
D-Glucaric acid (GA) is a value-added chemical produced from biomass, and has potential applications as a versatile platform chemical, food additive, metal sequestering agent, and therapeutic agent. Marketed GA is currently produced chemically, but increasing demand is driving the search for eco-friendlier and more efficient production approaches. Cell-based production of GA represents an alternative strategy for GA production. A series of synthetic pathways for GA have been ported into Escherichia coli, Saccharomyces cerevisiae and Pichia pastoris, respectively, and these engineered cells show the ability to synthesize GA de novo. Optimization of the GA metabolic pathways in host cells has leapt forward, and the titer and yield have increased rapidly. Meanwhile, cell-free multi-enzyme catalysis, in which the desired pathway is constructed in vitro from enzymes and cofactors involved in GA biosynthesis, has also realized efficient GA bioconversion. This review presents an overview of studies of the development of cell-based GA production, followed by a brief discussion of potential applications of biosensors that respond to GA in these biosynthesis routes.
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Affiliation(s)
- Lu-Zhou Chen
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China
| | - Si-Ling Huang
- Bloomage BioTechnology Corp., Ltd., Jinan, 250010, China
| | - Jin Hou
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Xue-Ping Guo
- Bloomage BioTechnology Corp., Ltd., Jinan, 250010, China
| | - Feng-Shan Wang
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China
- National Glycoengineering Research Center, Shandong University, Jinan, 250012, China
| | - Ju-Zheng Sheng
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China.
- National Glycoengineering Research Center, Shandong University, Jinan, 250012, China.
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Olavarria K, Carnet A, van Renselaar J, Quakkelaar C, Cabrera R, Guedes da Silva L, Smids AL, Villalobos PA, van Loosdrecht MCM, Wahl SA. An NADH preferring acetoacetyl-CoA reductase is engaged in poly-3-hydroxybutyrate accumulation in Escherichia coli. J Biotechnol 2020; 325:207-216. [PMID: 33122026 DOI: 10.1016/j.jbiotec.2020.10.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 10/16/2020] [Accepted: 10/18/2020] [Indexed: 01/08/2023]
Abstract
Oxygen supply implies higher production cost and reduction of maximum theoretical yields. Thus, generation of fermentation products is more cost-effective. Aiming to find a key piece for the production of (poly)-3-hydroxybutyrate (PHB) as a fermentation product, here we characterize an acetoacetyl-CoA reductase, isolated from a Candidatus Accumulibacter phosphatis-enriched mixed culture, showing a (kcatNADH/KMNADH)/(kcatNADPH/KMNADPH)>500. Further kinetic analyses indicate that, at physiological concentrations, this enzyme clearly prefers NADH, presenting the strongest NADH preference so far observed among the acetoacetyl-CoA reductases. Structural and kinetic analyses indicate that residues between E37 and P41 have an important role for the observed NADH preference. Moreover, an operon was assembled combining the phaCA genes from Cupriavidus necator and the gene encoding for this NADH-preferring acetoacetyl-CoA reductase. Escherichia coli cells expressing that assembled operon showed continuous accumulation of PHB under oxygen limiting conditions and PHB titer increased when decreasing the specific oxygen consumption rate. Taken together, these results show that it is possible to generate PHB as a fermentation product in E. coli, opening opportunities for further protein/metabolic engineering strategies envisioning a more efficient anaerobic production of PHB.
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Affiliation(s)
- Karel Olavarria
- Departement Biotechnologie, Faculteit Technische Natuurwetenschappen, Technische Universiteit Delft, Van der Maasweg 9, 2629 HZ, Netherlands.
| | - Alexandre Carnet
- Departement Biotechnologie, Faculteit Technische Natuurwetenschappen, Technische Universiteit Delft, Van der Maasweg 9, 2629 HZ, Netherlands.
| | - Joachim van Renselaar
- Departement Biotechnologie, Faculteit Technische Natuurwetenschappen, Technische Universiteit Delft, Van der Maasweg 9, 2629 HZ, Netherlands.
| | - Caspar Quakkelaar
- Departement Biotechnologie, Faculteit Technische Natuurwetenschappen, Technische Universiteit Delft, Van der Maasweg 9, 2629 HZ, Netherlands.
| | - Ricardo Cabrera
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Región Metropolitana, Chile.
| | - Leonor Guedes da Silva
- Departement Biotechnologie, Faculteit Technische Natuurwetenschappen, Technische Universiteit Delft, Van der Maasweg 9, 2629 HZ, Netherlands.
| | - Aron L Smids
- Departement Biotechnologie, Faculteit Technische Natuurwetenschappen, Technische Universiteit Delft, Van der Maasweg 9, 2629 HZ, Netherlands.
| | - Pablo Andres Villalobos
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Región Metropolitana, Chile.
| | - Mark C M van Loosdrecht
- Departement Biotechnologie, Faculteit Technische Natuurwetenschappen, Technische Universiteit Delft, Van der Maasweg 9, 2629 HZ, Netherlands.
| | - S Aljoscha Wahl
- Departement Biotechnologie, Faculteit Technische Natuurwetenschappen, Technische Universiteit Delft, Van der Maasweg 9, 2629 HZ, Netherlands.
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9
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Ellis GA, Tschirhart T, Spangler J, Walper SA, Medintz IL, Vora GJ. Exploiting the Feedstock Flexibility of the Emergent Synthetic Biology Chassis Vibrio natriegens for Engineered Natural Product Production. Mar Drugs 2019; 17:E679. [PMID: 31801279 PMCID: PMC6950413 DOI: 10.3390/md17120679] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/26/2019] [Accepted: 11/28/2019] [Indexed: 12/21/2022] Open
Abstract
A recent goal of synthetic biology has been to identify new chassis that provide benefits lacking in model organisms. Vibrio natriegens is a marine Gram-negative bacterium which is an emergent synthetic biology chassis with inherent benefits: An extremely fast growth rate, genetic tractability, and the ability to grow on a variety of carbon sources ("feedstock flexibility"). Given these inherent benefits, we sought to determine its potential to heterologously produce natural products, and chose beta-carotene and violacein as test cases. For beta-carotene production, we expressed the beta-carotene biosynthetic pathway from the sister marine bacterium Vibrio campbellii, as well as the mevalonate biosynthetic pathway from the Gram-positive bacterium Lactobacillus acidophilus to improve precursor abundance. Violacein was produced by expressing a biosynthetic gene cluster derived from Chromobacterium violaceum. Not only was V. natriegens able to heterologously produce these compounds in rich media, illustrating its promise as a new chassis for small molecule drug production, but it also did so in minimal media using a variety of feedstocks. The ability for V. natriegens to produce natural products with multiple industrially-relevant feedstocks argues for continued investigations into the production of more complex natural products in this chassis.
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Affiliation(s)
- Gregory A. Ellis
- Center for Bio/Molecular Science and Engineering, U.S. Naval Research Laboratory, Washington, DC 20375, USA; (G.A.E.); (S.A.W.); (I.L.M.)
| | - Tanya Tschirhart
- American Society for Engineering Education, Postdoctoral Research Associate, U.S. Naval Research Laboratory, Washington, DC 20375, USA
| | - Joseph Spangler
- National Academy of Sciences, National Research Council, Postdoctoral Research Associate, U.S. Naval Research Laboratory, Washington, DC 20375, USA;
| | - Scott A. Walper
- Center for Bio/Molecular Science and Engineering, U.S. Naval Research Laboratory, Washington, DC 20375, USA; (G.A.E.); (S.A.W.); (I.L.M.)
| | - Igor L. Medintz
- Center for Bio/Molecular Science and Engineering, U.S. Naval Research Laboratory, Washington, DC 20375, USA; (G.A.E.); (S.A.W.); (I.L.M.)
| | - Gary J. Vora
- Center for Bio/Molecular Science and Engineering, U.S. Naval Research Laboratory, Washington, DC 20375, USA; (G.A.E.); (S.A.W.); (I.L.M.)
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10
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Mohamed ET, Mundhada H, Landberg J, Cann I, Mackie RI, Nielsen AT, Herrgård MJ, Feist AM. Generation of an E. coli platform strain for improved sucrose utilization using adaptive laboratory evolution. Microb Cell Fact 2019; 18:116. [PMID: 31255177 PMCID: PMC6599523 DOI: 10.1186/s12934-019-1165-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Accepted: 06/22/2019] [Indexed: 01/01/2023] Open
Abstract
Background Sucrose is an attractive industrial carbon source due to its abundance and the fact that it can be cheaply generated from sources such as sugarcane. However, only a few characterized Escherichia coli strains are able to metabolize sucrose, and those that can are typically slow growing or pathogenic strains. Methods To generate a platform strain capable of efficiently utilizing sucrose with a high growth rate, adaptive laboratory evolution (ALE) was utilized to evolve engineered E. coli K-12 MG1655 strains containing the sucrose utilizing csc genes (cscB, cscK, cscA) alongside the native sucrose consuming E. coli W. Results Evolved K-12 clones displayed an increase in growth and sucrose uptake rates of 1.72- and 1.40-fold on sugarcane juice as compared to the original engineered strains, respectively, while E. coli W clones showed a 1.4-fold increase in sucrose uptake rate without a significant increase in growth rate. Whole genome sequencing of evolved clones and populations revealed that two genetic regions were frequently mutated in the K-12 strains; the global transcription regulatory genes rpoB and rpoC, and the metabolic region related to a pyrimidine biosynthetic deficiency in K-12 attributed to pyrE expression. These two mutated regions have been characterized to confer a similar benefit when glucose is the main carbon source, and reverse engineering revealed the same causal advantages on M9 sucrose. Additionally, the most prevalent mutation found in the evolved E. coli W lineages was the inactivation of the cscR gene, the transcriptional repression of sucrose uptake genes. Conclusion The generated K-12 and W platform strains, and the specific sets of mutations that enable their phenotypes, are available as valuable tools for sucrose-based industrial bioproduction in the facile E. coli chassis. Electronic supplementary material The online version of this article (10.1186/s12934-019-1165-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Elsayed T Mohamed
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Building 220, Kemitorvet, Lyngby, 2800 Kgs, Denmark
| | - Hemanshu Mundhada
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Building 220, Kemitorvet, Lyngby, 2800 Kgs, Denmark
| | - Jenny Landberg
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Building 220, Kemitorvet, Lyngby, 2800 Kgs, Denmark
| | - Isaac Cann
- Department of Animal Sciences, Institute for Genomic Biology and Energy Biosciences Institute, University of Illinois, Urbana, IL, 61801, USA
| | - Roderick I Mackie
- Department of Animal Sciences, Institute for Genomic Biology and Energy Biosciences Institute, University of Illinois, Urbana, IL, 61801, USA
| | - Alex Toftgaard Nielsen
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Building 220, Kemitorvet, Lyngby, 2800 Kgs, Denmark
| | - Markus J Herrgård
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Building 220, Kemitorvet, Lyngby, 2800 Kgs, Denmark
| | - Adam M Feist
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Building 220, Kemitorvet, Lyngby, 2800 Kgs, Denmark. .,Department of Bioengineering, University of California, 9500 Gilman Drive La Jolla, San Diego, CA, 92093, USA.
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Metabolism of sucrose in a non-fermentative Escherichia coli under oxygen limitation. Appl Microbiol Biotechnol 2019; 103:6245-6256. [PMID: 31147757 PMCID: PMC6616217 DOI: 10.1007/s00253-019-09909-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 05/10/2019] [Accepted: 05/11/2019] [Indexed: 01/21/2023]
Abstract
Biotechnological industry strives to develop anaerobic bioprocesses fueled by abundant and cheap carbon sources, like sucrose. However, oxygen-limiting conditions often lead to by-product formation and reduced ATP yields. While by-product formation is typically decreased by gene deletion, the breakdown of oligosaccharides with inorganic phosphate instead of water could increment the ATP yield. To observe the effect of oxygen limitation during sucrose consumption, a non-fermentative Escherichia coli K-12 strain was transformed with genes enabling sucrose assimilation. It was observed that the combined deletion of the genes adhE, adhP, mhpF, ldhA, and pta abolished the anaerobic growth using sucrose. Therefore, the biomass-specific conversion rates were obtained using oxygen-limited continuous cultures. Strains performing the breakdown of the sucrose by hydrolysis (SUC-HYD) or phosphorolysis (SUC-PHOSP) were studied in such conditions. An experimentally validated in silico model, modified to account for plasmid and protein burdens, was employed to calculate carbon and electron consistent conversion rates. In both strains, the biomass yields were lower than expected and, strikingly, SUC-PHOSP showed a yield lower than SUC-HYD. Flux balance analyses indicated a significant increase in the non-growth-associated ATP expenses by comparison with the growth on glucose. The observed fructose-1,6-biphosphatase and phosphoglucomutase activities, as well as the concentrations of glycogen, suggest the operation of ATP futile cycles triggered by a combination of the oxygen limitation and the metabolites released during the sucrose breakdown.
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12
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Pekar JE, Phaneuf P, Szubin R, Palsson B, Feist A, Monk JM. Gapless, Unambiguous Genome Sequence for Escherichia coli C, a Workhorse of Industrial Biology. Microbiol Resour Announc 2018; 7:e00890-18. [PMID: 30533692 PMCID: PMC6256561 DOI: 10.1128/mra.00890-18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 09/06/2018] [Indexed: 11/20/2022] Open
Abstract
Escherichia coli C is a commonly used strain in the bioprocessing industry, but despite its utility, the publicly available sequence of the E. coli C genome has gaps and 4,180 ambiguous base calls. Here, we present an updated, high-quality, unambiguous genome sequence with no assembly gaps.
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Affiliation(s)
- Jonathan E. Pekar
- Bioengineering Department, University of California San Diego, La Jolla, California, USA
| | - Patrick Phaneuf
- Bioengineering Department, University of California San Diego, La Jolla, California, USA
| | - Richard Szubin
- Bioengineering Department, University of California San Diego, La Jolla, California, USA
| | - Bernhard Palsson
- Bioengineering Department, University of California San Diego, La Jolla, California, USA
| | - Adam Feist
- Bioengineering Department, University of California San Diego, La Jolla, California, USA
| | - Jonathan M. Monk
- Bioengineering Department, University of California San Diego, La Jolla, California, USA
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13
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Biosynthesis of D-glucaric acid from sucrose with routed carbon distribution in metabolically engineered Escherichia coli. Metab Eng 2018; 47:393-400. [DOI: 10.1016/j.ymben.2018.04.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 04/25/2018] [Accepted: 04/27/2018] [Indexed: 01/09/2023]
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Alonso‐Gutierrez J, Koma D, Hu Q, Yang Y, Chan LJG, Petzold CJ, Adams PD, Vickers CE, Nielsen LK, Keasling JD, Lee TS. Toward industrial production of isoprenoids in
Escherichia coli
: Lessons learned from CRISPR‐Cas9 based optimization of a chromosomally integrated mevalonate pathway. Biotechnol Bioeng 2018; 115:1000-1013. [DOI: 10.1002/bit.26530] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 12/18/2017] [Accepted: 12/22/2017] [Indexed: 01/13/2023]
Affiliation(s)
- Jorge Alonso‐Gutierrez
- Joint BioEnergy Institute (JBEI)EmeryvilleCalifornia
- Biological Systems and Engineering DivisionLawrence Berkeley National LaboratoryBerkeleyCalifornia
| | - Daisuke Koma
- Joint BioEnergy Institute (JBEI)EmeryvilleCalifornia
- Biological Systems and Engineering DivisionLawrence Berkeley National LaboratoryBerkeleyCalifornia
- Osaka Municipal Technical Research InstituteOsakaJapan
| | - Qijun Hu
- Joint BioEnergy Institute (JBEI)EmeryvilleCalifornia
- Biological Systems and Engineering DivisionLawrence Berkeley National LaboratoryBerkeleyCalifornia
| | - Yuchen Yang
- Joint BioEnergy Institute (JBEI)EmeryvilleCalifornia
- Biological Systems and Engineering DivisionLawrence Berkeley National LaboratoryBerkeleyCalifornia
| | - Leanne J. G. Chan
- Joint BioEnergy Institute (JBEI)EmeryvilleCalifornia
- Biological Systems and Engineering DivisionLawrence Berkeley National LaboratoryBerkeleyCalifornia
| | - Christopher J. Petzold
- Joint BioEnergy Institute (JBEI)EmeryvilleCalifornia
- Biological Systems and Engineering DivisionLawrence Berkeley National LaboratoryBerkeleyCalifornia
| | - Paul D. Adams
- Joint BioEnergy Institute (JBEI)EmeryvilleCalifornia
- Molecular Biophysics and Integrated Bioimaging DivisionLawrence Berkeley National LaboratoryBerkeleyCalifornia
| | - Claudia E. Vickers
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandSt. LuciaQueenslandAustralia
| | - Lars K. Nielsen
- Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandSt. LuciaQueenslandAustralia
| | - Jay D. Keasling
- Joint BioEnergy Institute (JBEI)EmeryvilleCalifornia
- Biological Systems and Engineering DivisionLawrence Berkeley National LaboratoryBerkeleyCalifornia
- The Novo Nordisk Foundation Center for BiosustainabilityTechnical University of DenmarkHorsholmDenmark
- Department of Chemical and Biomolecular EngineeringUniversity of CaliforniaBerkeleyCalifornia
- Department of BioengineeringUniversity of CaliforniaBerkeleyCalifornia
| | - Taek S. Lee
- Joint BioEnergy Institute (JBEI)EmeryvilleCalifornia
- Biological Systems and Engineering DivisionLawrence Berkeley National LaboratoryBerkeleyCalifornia
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Feng J, Gu Y, Quan Y, Gao W, Dang Y, Cao M, Lu X, Wang Y, Song C, Wang S. Construction of energy-conserving sucrose utilization pathways for improving poly-γ-glutamic acid production in Bacillus amyloliquefaciens. Microb Cell Fact 2017; 16:98. [PMID: 28587617 PMCID: PMC5461702 DOI: 10.1186/s12934-017-0712-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Accepted: 06/01/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Sucrose is an naturally abundant and easily fermentable feedstock for various biochemical production processes. By now, several sucrose utilization pathways have been identified and characterized. Among them, the pathway consists of sucrose permease and sucrose phosphorylase is an energy-conserving sucrose utilization pathway because it consumes less ATP when comparing to other known pathways. Bacillus amyloliquefaciens NK-1 strain can use sucrose as the feedstock to produce poly-γ-glutamic acid (γ-PGA), a highly valuable biopolymer. The native sucrose utilization pathway in NK-1 strain consists of phosphoenolpyruvate-dependent phosphotransferase system and sucrose-6-P hydrolase and consumes more ATP than the energy-conserving sucrose utilization pathway. RESULTS In this study, the native sucrose utilization pathway in NK-1 was firstly deleted and generated the B. amyloliquefaciens 3Δ strain. Then four combination of heterologous energy-conserving sucrose utilization pathways were constructed and introduced into the 3Δ strain. Results demonstrated that the combination of cscB (encodes sucrose permease) from Escherichia coli and sucP (encodes sucrose phosphorylase) from Bifidobacterium adolescentis showed the highest sucrose metabolic efficiency. The corresponding mutant consumed 49.4% more sucrose and produced 38.5% more γ-PGA than the NK-1 strain under the same fermentation conditions. CONCLUSIONS To our best knowledge, this is the first report concerning the enhancement of the target product production by introducing the heterologous energy-conserving sucrose utilization pathways. Such a strategy can be easily extended to other microorganism hosts for reinforced biochemical production using sucrose as substrate.
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Affiliation(s)
- Jun Feng
- Key Laboratory of Molecular Microbiology and Technology for Ministry of Education, Nankai University, Tianjin, 300071, China.,Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, Shaanxi, China.,Department of Biosystems Engineering, Auburn University, Auburn, AL, 36849, USA.,State Key Laboratory of Medicinal Chemical Biology, Nankai University, 94 Weijin Road, Tianjin, 300071, China
| | - Yanyan Gu
- Key Laboratory of Molecular Microbiology and Technology for Ministry of Education, Nankai University, Tianjin, 300071, China.,Department of Biosystems Engineering, Auburn University, Auburn, AL, 36849, USA
| | - Yufen Quan
- Key Laboratory of Molecular Microbiology and Technology for Ministry of Education, Nankai University, Tianjin, 300071, China
| | - Weixia Gao
- Key Laboratory of Molecular Microbiology and Technology for Ministry of Education, Nankai University, Tianjin, 300071, China
| | - Yulei Dang
- Key Laboratory of Molecular Microbiology and Technology for Ministry of Education, Nankai University, Tianjin, 300071, China
| | - Mingfeng Cao
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Xiaoyun Lu
- Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, Shaanxi, China
| | - Yi Wang
- Department of Biosystems Engineering, Auburn University, Auburn, AL, 36849, USA
| | - Cunjiang Song
- Key Laboratory of Molecular Microbiology and Technology for Ministry of Education, Nankai University, Tianjin, 300071, China.
| | - Shufang Wang
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, 94 Weijin Road, Tianjin, 300071, China.
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Peng B, Plan MR, Carpenter A, Nielsen LK, Vickers CE. Coupling gene regulatory patterns to bioprocess conditions to optimize synthetic metabolic modules for improved sesquiterpene production in yeast. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:43. [PMID: 28239415 PMCID: PMC5320780 DOI: 10.1186/s13068-017-0728-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 02/09/2017] [Indexed: 05/23/2023]
Abstract
BACKGROUND Assembly of heterologous metabolic pathways is commonly required to generate microbial cell factories for industrial production of both commodity chemicals (including biofuels) and high-value chemicals. Promoter-mediated transcriptional regulation coordinates the expression of the individual components of these heterologous pathways. Expression patterns vary during culture as conditions change, and this can influence yeast physiology and productivity in both positive and negative ways. Well-characterized strategies are required for matching transcriptional regulation with desired output across changing culture conditions. RESULTS Here, constitutive and inducible regulatory mechanisms were examined to optimize synthetic isoprenoid metabolic pathway modules for production of trans-nerolidol, an acyclic sesquiterpene alcohol, in yeast. The choice of regulatory system significantly affected physiological features (growth and productivity) over batch cultivation. Use of constitutive promoters resulted in poor growth during the exponential phase. Delaying expression of the assembled metabolic modules using the copper-inducible CUP1 promoter resulted in a 1.6-fold increase in the exponential-phase growth rate and a twofold increase in productivity in the post-exponential phase. However, repeated use of the CUP1 promoter in multiple expression cassettes resulted in genetic instability. A diauxie-inducible expression system, based on an engineered GAL regulatory circuit and a set of four different GAL promoters, was characterized and employed to assemble nerolidol synthetic metabolic modules. Nerolidol production was further improved by 60% to 392 mg L-1 using this approach. Various carbon source systems were investigated in batch/fed-batch cultivation to regulate induction through the GAL system; final nerolidol titres of 4-5.5 g L-1 were achieved, depending on the conditions. CONCLUSION Direct comparison of different transcriptional regulatory mechanisms clearly demonstrated that coupling the output strength to the fermentation stage is important to optimize the growth fitness and overall productivities of engineered cells in industrially relevant processes. Applying different well-characterized promoters with the same induction behaviour mitigates against the risks of homologous sequence-mediated genetic instability. Using these approaches, we significantly improved sesquiterpene production in yeast.
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Affiliation(s)
- Bingyin Peng
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, St. Lucia, QLD 4072 Australia
| | - Manuel R. Plan
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, St. Lucia, QLD 4072 Australia
- Metabolomics Australia (Queensland Node), The University of Queensland, St. Lucia, QLD 4072 Australia
| | - Alexander Carpenter
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, St. Lucia, QLD 4072 Australia
| | - Lars K. Nielsen
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, St. Lucia, QLD 4072 Australia
| | - Claudia E. Vickers
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, St. Lucia, QLD 4072 Australia
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17
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Peng B, Plan MR, Chrysanthopoulos P, Hodson MP, Nielsen LK, Vickers CE. A squalene synthase protein degradation method for improved sesquiterpene production in Saccharomyces cerevisiae. Metab Eng 2017; 39:209-219. [DOI: 10.1016/j.ymben.2016.12.003] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 11/17/2016] [Accepted: 12/07/2016] [Indexed: 10/20/2022]
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Monk JM, Koza A, Campodonico MA, Machado D, Seoane JM, Palsson BO, Herrgård MJ, Feist AM. Multi-omics Quantification of Species Variation of Escherichia coli Links Molecular Features with Strain Phenotypes. Cell Syst 2016; 3:238-251.e12. [PMID: 27667363 DOI: 10.1016/j.cels.2016.08.013] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 03/25/2016] [Accepted: 08/19/2016] [Indexed: 11/16/2022]
Abstract
Escherichia coli strains are widely used in academic research and biotechnology. New technologies for quantifying strain-specific differences and their underlying contributing factors promise greater understanding of how these differences significantly impact physiology, synthetic biology, metabolic engineering, and process design. Here, we quantified strain-specific differences in seven widely used strains of E. coli (BL21, C, Crooks, DH5a, K-12 MG1655, K-12 W3110, and W) using genomics, phenomics, transcriptomics, and genome-scale modeling. Metabolic physiology and gene expression varied widely with downstream implications for productivity, product yield, and titer. These differences could be linked to differential regulatory structure. Analyzing high-flux reactions and expression of encoding genes resulted in a correlated and quantitative link between these sets, with strain-specific caveats. Integrated modeling revealed that certain strains are better suited to produce given compounds or express desired constructs considering native expression states of pathways that enable high-production phenotypes. This study yields a framework for quantitatively comparing strains in a species with implications for strain selection.
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Affiliation(s)
- Jonathan M Monk
- Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Anna Koza
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark
| | - Miguel A Campodonico
- Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0412, USA; Centre for Biotechnology and Bioengineering, CeBiB, University of Chile, Beauchef 850, Santiago, Chile
| | - Daniel Machado
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark
| | - Jose Miguel Seoane
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark
| | - Bernhard O Palsson
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark; Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0412, USA
| | - Markus J Herrgård
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark
| | - Adam M Feist
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2970 Hørsholm, Denmark; Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0412, USA.
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Williams TC, Espinosa MI, Nielsen LK, Vickers CE. Dynamic regulation of gene expression using sucrose responsive promoters and RNA interference in Saccharomyces cerevisiae. Microb Cell Fact 2015; 14:43. [PMID: 25886317 PMCID: PMC4427958 DOI: 10.1186/s12934-015-0223-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 03/06/2015] [Indexed: 11/24/2022] Open
Abstract
Background Engineering dynamic, environmentally- and temporally-responsive control of gene expression is one of the principle objectives in the field of synthetic biology. Dynamic regulation is desirable because many engineered functions conflict with endogenous processes which have evolved to facilitate growth and survival, and minimising conflict between growth and production phases can improve product titres in microbial cell factories. There are a limited number of mechanisms that enable dynamic regulation in yeast, and fewer still that are appropriate for application in an industrial setting. Results To address this problem we have identified promoters that are repressed during growth on glucose, and activated during growth on sucrose. Catabolite repression and preferential glucose utilisation allows active growth on glucose before switching to production on sucrose. Using sucrose as an activator of gene expression circumvents the need for expensive inducer compounds and enables gene expression to be triggered during growth on a fermentable, high energy-yield carbon source. The ability to fine-tune the timing and population density at which gene expression is activated from the SUC2 promoter was demonstrated by varying the ratio of glucose to sucrose in the growth medium. Finally, we demonstrated that the system could also be used to repress gene expression (a process also required for many engineering projects). We used the glucose/sucrose system to control a heterologous RNA interference module and dynamically repress the expression of a constitutively regulated GFP gene. Conclusions The low noise levels and high dynamic range of the SUC2 promoter make it a promising option for implementing dynamic regulation in yeast. The capacity to repress gene expression using RNA interference makes the system highly versatile, with great potential for metabolic engineering applications. Electronic supplementary material The online version of this article (doi:10.1186/s12934-015-0223-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Thomas C Williams
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, St. Lucia, QLD, 4072, Australia.
| | - Monica I Espinosa
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, St. Lucia, QLD, 4072, Australia.
| | - Lars K Nielsen
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, St. Lucia, QLD, 4072, Australia.
| | - Claudia E Vickers
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, St. Lucia, QLD, 4072, Australia.
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21
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Production of Industrially Relevant Isoprenoid Compounds in Engineered Microbes. MICROORGANISMS IN BIOREFINERIES 2015. [DOI: 10.1007/978-3-662-45209-7_11] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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22
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Protocols for the Production and Analysis of Isoprenoids in Bacteria and Yeast. SPRINGER PROTOCOLS HANDBOOKS 2015. [DOI: 10.1007/8623_2015_107] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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23
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The transport and mediation mechanisms of the common sugars in Escherichia coli. Biotechnol Adv 2014; 32:905-19. [DOI: 10.1016/j.biotechadv.2014.04.009] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 03/23/2014] [Accepted: 04/18/2014] [Indexed: 11/17/2022]
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Bruschi M, Krömer JO, Steen JA, Nielsen LK. Production of the short peptide surfactant DAMP4 from glucose or sucrose in high cell density cultures of Escherichia coli BL21(DE3). Microb Cell Fact 2014; 13:99. [PMID: 25134850 PMCID: PMC4229601 DOI: 10.1186/s12934-014-0099-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 06/26/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Peptides are increasingly used in industry as highly functional materials. Bacterial production of recombinant peptides has the potential to provide large amounts of renewable and low cost peptides, however, achieving high product titers from Chemically Defined Media (CDM) supplemented with simple sugars remains challenging. RESULTS In this work, the short peptide surfactant, DAMP4, was used as a model peptide to investigate production in Escherichia coli BL21(DE3), a classical strain used for protein production. Under the same fermentation conditions, switching production of DAMP4 from rich complex media to CDM resulted in a reduction in yield that could be attributed to the reduction in final cell density more so than a significant reduction in specific productivity. To maximize product titer, cell density at induction was maximized using a fed-batch approach. In fed-batch DAMP4 product titer increased 9-fold compared to batch, while maintaining 60% specific productivity. Under the fed-batch conditions, the final product titer of DAMP4 reached more than 7 g/L which is the highest titer of DAMP4 reported to date. To investigate production from sucrose, sucrose metabolism was engineered into BL21(DE3) using a simple plasmid approach. Using this strain, growth and DAMP4 production characteristics obtained from CDM supplemented with sucrose were similar to those obtained when culturing the parent strain on CDM supplemented with glucose. CONCLUSIONS Production of a model peptide was increased to several grams per liter using a CDM medium with either glucose or sucrose feedstock. It is hoped that this work will contribute cost reduction for production of designer peptide surfactants to facilitate their commercial application.
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Affiliation(s)
| | - Jens O Krömer
- Centre for Microbial Electrosynthesis (CEMES), Advanced Water Management Centre (AWMC), Research Road (Bldg 60), The University of Queensland, St, Lucia 4072, QLD, Australia.
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Vickers CE, Bongers M, Liu Q, Delatte T, Bouwmeester H. Metabolic engineering of volatile isoprenoids in plants and microbes. PLANT, CELL & ENVIRONMENT 2014; 37:1753-75. [PMID: 24588680 DOI: 10.1111/pce.12316] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Revised: 02/18/2014] [Accepted: 02/18/2014] [Indexed: 05/09/2023]
Abstract
The chemical properties and diversity of volatile isoprenoids lends them to a broad variety of biological roles. It also lends them to a host of biotechnological applications, both by taking advantage of their natural functions and by using them as industrial chemicals/chemical feedstocks. Natural functions include roles as insect attractants and repellents, abiotic stress protectants in pathogen defense, etc. Industrial applications include use as pharmaceuticals, flavours, fragrances, fuels, fuel additives, etc. Here we will examine the ways in which researchers have so far found to exploit volatile isoprenoids using biotechnology. Production and/or modification of volatiles using metabolic engineering in both plants and microorganisms are reviewed, including engineering through both mevalonate and methylerythritol diphosphate pathways. Recent advances are illustrated using several case studies (herbivores and bodyguards, isoprene, and monoterpene production in microbes). Systems and synthetic biology tools with particular utility for metabolic engineering are also reviewed. Finally, we discuss the practical realities of various applications in modern biotechnology, explore possible future applications, and examine the challenges of moving these technologies forward so that they can deliver tangible benefits. While this review focuses on volatile isoprenoids, many of the engineering approaches described here are also applicable to non-isoprenoid volatiles and to non-volatile isoprenoids.
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Affiliation(s)
- Claudia E Vickers
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, Queensland, 4072, Australia
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Steen JA, Bohlke N, Vickers CE, Nielsen LK. The trehalose phosphotransferase system (PTS) in E. coli W can transport low levels of sucrose that are sufficient to facilitate induction of the csc sucrose catabolism operon. PLoS One 2014; 9:e88688. [PMID: 24586369 PMCID: PMC3938415 DOI: 10.1371/journal.pone.0088688] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 01/09/2014] [Indexed: 11/24/2022] Open
Abstract
Plasticity in substrate acceptance is a well-characterised phenomenon for disaccharide transporters. Sucrose, a non-reducing disaccharide, is usually metabolised via either the permease-mediated chromosomally-encoded sucrose catabolism (csc) regulon or the sucrose phosphotransferase system (PTS). E. coli W is a fast-growing strain which efficiently utilises sucrose at concentrations above 1% via the csc regulon. To examine if sucrose could be metabolised via other routes, a library of transposon mutants was generated and screened on 0.2% sucrose. One mutant identified from this library had an insertion in the repressor for the regulon controlling catabolism of the disaccharide trehalose (treR). A series of mutants was constructed to elucidate the mechanism of sucrose utilization in the treR insertion strain. Analysis of these mutants provided evidence that deletion of TreR enables uptake of sucrose via TreB, an enzyme II protein required for PTS-mediated uptake of trehalose. Once inside the cell, this sucrose is not processed by the TreC hydrolase, nor is it sufficient for growth of the strain. QRT-PCR analysis showed that levels of cscA (invertase) transcript increased in the WΔtreR mutant relative to the wild-type strain when grown under low sucrose conditions. This result suggests that the intracellular sucrose provided by TreB can facilitate de-repression of the csc regulon, leading to increased gene expression, sucrose uptake and sucrose utilization in the treR mutant.
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Affiliation(s)
- Jennifer A. Steen
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Brisbane, Queensland, Australia
| | - Nina Bohlke
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Brisbane, Queensland, Australia
| | - Claudia E. Vickers
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Brisbane, Queensland, Australia
- * E-mail:
| | - Lars K. Nielsen
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Brisbane, Queensland, Australia
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Dual gene expression cassette vectors with antibiotic selection markers for engineering in Saccharomyces cerevisiae. Microb Cell Fact 2013; 12:96. [PMID: 24161108 PMCID: PMC4231455 DOI: 10.1186/1475-2859-12-96] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 10/20/2013] [Indexed: 02/01/2023] Open
Abstract
Background Manipulations in Saccharomyces cerevisiae classically depend on use of auxotrophy selection markers. There are several disadvantages to this in a microbial cell factory setting: (1) auxotrophies must first be engineered in prototrophic strains, and many industrial strains are polyploid/aneuploid prototrophs (2) available strain auxotrophies must be paired with available repair plasmids (3) remaining auxotrophies must be repaired prior to development of industrial bioprocesses. Use of dominant antibiotic resistance markers can circumvent these problems. However, there are relatively few yeast antibiotic resistance marker vectors available; furthermore, available vectors contain only one expression cassette, and it is often desirable to introduce more than one gene at a time. Results To overcome these problems, eight new shuttle vectors have been developed. The plasmids are maintained in yeast under a 2 μm ori and in E. coli by a pUC ori. They contain two yeast expression cassettes driven by either (1) the constitutive TEF1 and PGK1 promoters, or (2) the constitutive TEF1 promoter and the inducible GAL10 or HXT7 promoters. Expression strength of these promoters over a typical production time frame in glucose/galactose medium was examined, and identified the TEF1 and HXT7 promoters as preferred promoters over long term fermentations. Selection is provided by either aphA1 (conferring resistance to G418 in yeast and kanamycin/neomycin in E. coli) or ble (conferring resistance to phleomycin in both yeast and E. coli). Selection conditions for these plasmids/antibiotics in defined media were examined, and selection considerations are reviewed. In particular, medium pH has a strong effect on both G418 and phleomycin selection. Conclusions These vectors allow manipulations in prototrophic yeast strains with expression of two gene cassettes per plasmid, and will be particularly useful for metabolic engineering applications. The vector set expands the (currently limited) selection of antibiotic marker plasmids available for use in yeast, and in addition makes available dual gene expression cassettes on individual plasmids using antibiotic selection. The resistance gene cassettes are flanked by loxP recognition sites to allow CreA-mediated marker removal and recycling, providing the potential for genomic integration of multiple genes. Guidelines for selection using G418 and phleomycin are provided.
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Du W, Liang F, Duan Y, Tan X, Lu X. Exploring the photosynthetic production capacity of sucrose by cyanobacteria. Metab Eng 2013; 19:17-25. [DOI: 10.1016/j.ymben.2013.05.001] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Revised: 05/08/2013] [Accepted: 05/15/2013] [Indexed: 10/26/2022]
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Sabri S, Steen JA, Bongers M, Nielsen LK, Vickers CE. Knock-in/Knock-out (KIKO) vectors for rapid integration of large DNA sequences, including whole metabolic pathways, onto the Escherichia coli chromosome at well-characterised loci. Microb Cell Fact 2013; 12:60. [PMID: 23799955 PMCID: PMC3706339 DOI: 10.1186/1475-2859-12-60] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 05/23/2013] [Indexed: 11/21/2022] Open
Abstract
Background Metabolic engineering projects often require integration of multiple genes in order to control the desired phenotype. However, this often requires iterative rounds of engineering because many current insertion approaches are limited by the size of the DNA that can be transferred onto the chromosome. Consequently, construction of highly engineered strains is very time-consuming. A lack of well-characterised insertion loci is also problematic. Results A series of knock-in/knock-out (KIKO) vectors was constructed for integration of large DNA sequences onto the E. coli chromosome at well-defined loci. The KIKO plasmids target three nonessential genes/operons as insertion sites: arsB (an arsenite transporter); lacZ (β-galactosidase); and rbsA-rbsR (a ribose metabolism operon). Two homologous ‘arms’ target each insertion locus; insertion is mediated by λ Red recombinase through these arms. Between the arms is a multiple cloning site for the introduction of exogenous sequences and an antibiotic resistance marker (either chloramphenicol or kanamycin) for selection of positive recombinants. The resistance marker can subsequently be removed by flippase-mediated recombination. The insertion cassette is flanked by hairpin loops to isolate it from the effects of external transcription at the integration locus. To characterize each target locus, a xylanase reporter gene (xynA) was integrated onto the chromosomes of E. coli strains W and K-12 using the KIKO vectors. Expression levels varied between loci, with the arsB locus consistently showing the highest level of expression. To demonstrate the simultaneous use of all three loci in one strain, xynA, green fluorescent protein (gfp) and a sucrose catabolic operon (cscAKB) were introduced into lacZ, arsB and rbsAR respectively, and shown to be functional. Conclusions The KIKO plasmids are a useful tool for efficient integration of large DNA fragments (including multiple genes and pathways) into E. coli. Chromosomal insertion provides stable expression without the need for continuous antibiotic selection. Three non-essential loci have been characterised as insertion loci; combinatorial insertion at all three loci can be performed in one strain. The largest insertion at a single site described here was 5.4 kb; we have used this method in other studies to insert a total of 7.3 kb at one locus and 11.3 kb across two loci. These vectors are particularly useful for integration of multigene cassettes for metabolic engineering applications.
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Affiliation(s)
- Suriana Sabri
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia
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Janezic KJ, Ferry B, Hendricks EW, Janiga BA, Johnson T, Murphy S, Roberts ME, Scott SM, Theisen AN, Hung KF, Daniel SL. Phenotypic and Genotypic Characterization of Escherichia coli Isolated from Untreated Surface Waters. Open Microbiol J 2013; 7:9-19. [PMID: 23539437 PMCID: PMC3606946 DOI: 10.2174/1874285801307010009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/28/2013] [Accepted: 01/30/2013] [Indexed: 11/22/2022] Open
Abstract
A common member of the intestinal microbiota in humans and animals is Escherichia coli. Based on the presence of virulence factors, E. coli can be potentially pathogenic. The focus of this study was to isolate E. coli from untreated surface waters (37 sites) in Illinois and Missouri and determine phenotypic and genotypic diversity among isolates. Water samples positive for fecal coliforms based on the Colisure® test were streaked directly onto Eosin Methylene Blue (EMB) agar (37°C) or transferred to EC broth (44.5°C). EC broth cultures producing gas were then streaked onto EMB agar. Forty-five isolates were identified as E. coli using API 20E and Enterotube II identification systems, and some phenotypic variation was observed in metabolism and fermentation. Antibiotic susceptibility of each isolate was also determined using the Kirby-Bauer Method. Differential responses to 10 antimicrobial agents were seen with 7, 16, 2, and 9 of the isolates resistant to ampicillin, cephalothin, tetracycline, and triple sulfonamide, respectively. All of the isolates were susceptible or intermediate to amoxicillin, ciprofloxacin, polymyxin B, gentamicin, imipenem, and nalidixic acid. Genotypic variation was assessed through multiplex Polymerase Chain Reaction for four virulence genes (stx1 and stx2 [shiga toxin], eaeA [intimin]; and hlyA [enterohemolysin]) and one housekeeping gene (uidA [β-D-glucuronidase]). Genotypic variation was observed with two of the isolates possessing the virulence gene (eaeA) for intimin. These findings increase our understanding of the diversity of E. coli in the environment which will ultimately help in the assessment of this organism and its role in public health.
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Affiliation(s)
- Kristopher J Janezic
- Department of Biological Sciences, Eastern Illinois University, Charleston, Illinois 61920, USA
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Molecular control of sucrose utilization in Escherichia coli W, an efficient sucrose-utilizing strain. Appl Environ Microbiol 2012; 79:478-87. [PMID: 23124236 DOI: 10.1128/aem.02544-12] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sucrose is an industrially important carbon source for microbial fermentation. Sucrose utilization in Escherichia coli, however, is poorly understood, and most industrial strains cannot utilize sucrose. The roles of the chromosomally encoded sucrose catabolism (csc) genes in E. coli W were examined by knockout and overexpression experiments. At low sucrose concentrations, the csc genes are repressed and cells cannot grow. Removal of either the repressor protein (cscR) or the fructokinase (cscK) gene facilitated derepression. Furthermore, combinatorial knockout of cscR and cscK conferred an improved growth rate on low sucrose. The invertase (cscA) and sucrose transporter (cscB) genes are essential for sucrose catabolism in E. coli W, demonstrating that no other genes can provide sucrose transport or inversion activities. However, cscK is not essential for sucrose utilization. Fructose is excreted into the medium by the cscK-knockout strain in the presence of high sucrose, whereas at low sucrose (when carbon availability is limiting), fructose is utilized by the cell. Overexpression of cscA, cscAK, or cscAB could complement the WΔcscRKAB knockout mutant or confer growth on a K-12 strain which could not naturally utilize sucrose. However, phenotypic stability and relatively good growth rates were observed in the K-12 strain only when overexpressing cscAB, and full growth rate complementation in WΔcscRKAB also required cscAB. Our understanding of sucrose utilization can be used to improve E. coli W and engineer sucrose utilization in strains which do not naturally utilize sucrose, allowing substitution of sucrose for other, less desirable carbon sources in industrial fermentations.
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