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Yuzbashev TV, Yuzbasheva EY, Melkina OE, Patel D, Bubnov D, Dietz H, Ledesma-Amaro R. A DNA assembly toolkit to unlock the CRISPR/Cas9 potential for metabolic engineering. Commun Biol 2023; 6:858. [PMID: 37596335 PMCID: PMC10439232 DOI: 10.1038/s42003-023-05202-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Accepted: 08/01/2023] [Indexed: 08/20/2023] Open
Abstract
CRISPR/Cas9-based technologies are revolutionising the way we engineer microbial cells. One of the key advantages of CRISPR in strain design is that it enables chromosomal integration of marker-free DNA, eliminating laborious and often inefficient marker recovery procedures. Despite the benefits, assembling CRISPR/Cas9 editing systems is still not a straightforward process, which may prevent its use and applications. In this work, we have identified some of the main limitations of current Cas9 toolkits and designed improvements with the goal of making CRISPR technologies easier to access and implement. These include 1) A system to quickly switch between marker-free and marker-based integration constructs using both a Cre-expressing and standard Escherichia coli strains, 2) the ability to redirect multigene integration cassettes into alternative genomic loci via Golden Gate-based exchange of homology arms, 3) a rapid, simple in-vivo method to assembly guide RNA sequences via recombineering between Cas9-helper plasmids and single oligonucleotides. We combine these methodologies with well-established technologies into a comprehensive toolkit for efficient metabolic engineering using CRISPR/Cas9. As a proof of concept, we developed the YaliCraft toolkit for Yarrowia lipolytica, which is composed of a basic set of 147 plasmids and 7 modules with different purposes. We used the toolkit to generate and characterize a library of 137 promoters and to build a de novo strain synthetizing 373.8 mg/L homogentisic acid.
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Affiliation(s)
- Tigran V Yuzbashev
- Department of Bioengineering, Imperial College London, London, SW7 2AZ, UK.
- Plant Sciences and the Bioeconomy, Rothamsted Research, West Common, Harpenden, Hertfordshire, AL5 2JQ, UK.
| | | | - Olga E Melkina
- NRC 'Kurchatov Institute'-GosNIIgenetika, Kurchatov Genomic Centre, 1-st Dorozhny Pr., 1, Moscow, 117545, Russia
| | - Davina Patel
- Department of Bioengineering, Imperial College London, London, SW7 2AZ, UK
| | - Dmitrii Bubnov
- NRC 'Kurchatov Institute'-GosNIIgenetika, Kurchatov Genomic Centre, 1-st Dorozhny Pr., 1, Moscow, 117545, Russia
| | - Heiko Dietz
- Kaesler Research Institute, Kaesler Nutrition GmbH, Fischkai 1, 27572, Bremerhaven, Germany
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Wu XL, Liu XW, Wang Y, Guo MY, Ye JR. Optimization of Constitutive Promoters Using a Promoter-Trapping Vector in Burkholderia pyrrocinia JK-SH007. Int J Mol Sci 2023; 24:ijms24119419. [PMID: 37298372 DOI: 10.3390/ijms24119419] [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: 04/10/2023] [Revised: 05/16/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023] Open
Abstract
Selecting suitable promoters to drive gene overexpression can provide significant insight into the development of engineered bacteria. In this study, we analyzed the transcriptome data of Burkholderia pyrrocinia JK-SH007 and identified 54 highly expressed genes. The promoter sequences were located using genome-wide data and scored using the prokaryotic promoter prediction software BPROM to further screen out 18 promoter sequences. We also developed a promoter trap system based on two reporter proteins adapted for promoter optimization in B. pyrrocinia JK-SH007: firefly luciferase encoded by the luciferase gene set (Luc) and trimethoprim (TP)-resistant dihydrofolate reductase (TPr). Ultimately, eight constitutive promoters were successfully inserted into the probe vector and transformed into B. pyrrocinia JK-SH007. The transformants were successfully grown on Tp antibiotic plates, and firefly luciferase expression was determined by measuring the relative light unit (RLU). Five of the promoters (P4, P9, P10, P14, and P19) showed 1.01-2.51-fold higher activity than the control promoter λ phage transcriptional promoter (PRPL). The promoter activity was further validated via qPCR analysis, indicating that promoters P14 and P19 showed stable high transcription levels at all time points. Then, GFP and RFP proteins were overexpressed in JK-SH007. In addition, promoters P14 and P19 were successfully used to drive gene expression in Burkholderia multivorans WS-FJ9 and Escherichia coli S17-1. The two constitutive promoters can be used not only in B. pyrrocinia JK-SH007 itself to gene overexpression but also to expand the scope of application.
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Affiliation(s)
- Xue-Lian Wu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing 210037, China
| | - Xiao-Wei Liu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing 210037, China
| | - Yang Wang
- Institute of Forest Pest Control, Jiangxi Academy of Forestry, Nanchang 330032, China
| | - Meng-Yun Guo
- Key Laboratory for Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu 610065, China
| | - Jian-Ren Ye
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing 210037, China
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Meng F, Zhu X, Nie T, Lu F, Bie X, Lu Y, Trouth F, Lu Z. Enhanced Expression of Pullulanase in Bacillus subtilis by New Strong Promoters Mined From Transcriptome Data, Both Alone and in Combination. Front Microbiol 2018; 9:2635. [PMID: 30450090 PMCID: PMC6224515 DOI: 10.3389/fmicb.2018.02635] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 10/16/2018] [Indexed: 11/13/2022] Open
Abstract
Pullulanase plays an important role as a starch hydrolysis enzyme in the production of bio-fuels and animal feed, and in the food industry. Compared to the methods currently used for pullulanase production, synthesis by Bacillus subtilis would be safer and easier. However, the current yield of pullulanase from B. subtilis is low to meet industrial requirements. Therefore, it is necessary to improve the yield of pullulanase by B. subtilis. In this study, we mined 10 highly active promoters from B. subtilis based on transcriptome and bioinformatic data. Individual promoters and combinations of promoters were used to improve the yield of pullulanase in B. subtilis BS001. Four recombinant strains with new promoters (Phag, PtufA, PsodA, and PfusA) had higher enzyme activity than the control (PamyE). The strain containing PsodA+fusA (163 U/mL) and the strain containing PsodA+fusA+amyE (336 U/mL) had the highest activity among the analyzed dual- and triple-promoter construct stains in shake flask, which were 2.29 and 4.73 times higher than that of the strain with PamyE, respectively. Moreover, the activity of the strain containing PsodA+fusA+amyE showed a maximum activity of 1,555 U/mL, which was 21.9 times higher than that of the flask-grown PamyE strain in a 50-liter fermenter. Our work showed that these four strong promoters mined from transcriptome data and their combinations could reliably increase the yield of pullulanase in quantities suitable for industrial applications.
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Affiliation(s)
- Fanqiang Meng
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Xiaoyu Zhu
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Ting Nie
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Fengxia Lu
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Xiaomei Bie
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Yingjian Lu
- Department of Food Science and Nutrition, University of Maryland, College Park, MD, United States
| | - Frances Trouth
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, United States
| | - Zhaoxin Lu
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
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Chai R, Qiu C, Liu D, Qi Y, Gao Y, Shen J, Qiu L. β-Glucan synthase gene overexpression and β-glucans overproduction in Pleurotus ostreatus using promoter swapping. PLoS One 2013; 8:e61693. [PMID: 23637884 PMCID: PMC3634845 DOI: 10.1371/journal.pone.0061693] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Accepted: 03/13/2013] [Indexed: 11/19/2022] Open
Abstract
Mushroom β-glucans are potent immunological stimulators in medicine, but their productivities are very low. In this study, we successfully improved its production by promoter engineering in Pleurotus ostreatus. The promoter for β-1,3-glucan synthase gene (GLS) was replaced by the promoter of glyceraldehyde-3-phosphate dehydrogenase gene of Aspergillus nidulans. The homologous recombination fragment for swapping GLS promoter comprised five segments, which were fused by two rounds of combined touchdown PCR and overlap extension PCR (TD-OE PCR), and was introduced into P. ostreatus through PEG/CaCl2-mediated protoplast transformation. The transformants exhibited one to three fold higher transcription of GLS gene and produced 32% to 131% higher yield of β-glucans than the wild type. The polysaccharide yields had a significant positive correlation to the GLS gene expression. The infrared spectra of the polysaccharides all displayed the typical absorption peaks of β-glucans. This is the first report of successful swapping of promoters in filamentous fungi.
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Affiliation(s)
- Ran Chai
- College of Life Sciences, Henan Agricultural University, Zhengzhou, People's Republic of China
- Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Zhengzhou, People's Republic of China
| | - Cuiwei Qiu
- College of Life Sciences, Henan Agricultural University, Zhengzhou, People's Republic of China
- Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Zhengzhou, People's Republic of China
| | - Dongren Liu
- College of Life Sciences, Henan Agricultural University, Zhengzhou, People's Republic of China
- Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Zhengzhou, People's Republic of China
| | - Yuancheng Qi
- College of Life Sciences, Henan Agricultural University, Zhengzhou, People's Republic of China
- Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Zhengzhou, People's Republic of China
| | - Yuqian Gao
- College of Life Sciences, Henan Agricultural University, Zhengzhou, People's Republic of China
- Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Zhengzhou, People's Republic of China
| | - Jinwen Shen
- College of Life Sciences, Henan Agricultural University, Zhengzhou, People's Republic of China
- Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Zhengzhou, People's Republic of China
| | - Liyou Qiu
- College of Life Sciences, Henan Agricultural University, Zhengzhou, People's Republic of China
- Key Laboratory of Enzyme Engineering of Agricultural Microbiology, Ministry of Agriculture, Zhengzhou, People's Republic of China
- * E-mail:
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Jarboe LR, Liu P, Kautharapu KB, Ingram LO. Optimization of enzyme parameters for fermentative production of biorenewable fuels and chemicals. Comput Struct Biotechnol J 2012; 3:e201210005. [PMID: 24688665 PMCID: PMC3962213 DOI: 10.5936/csbj.201210005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2012] [Revised: 10/21/2012] [Accepted: 10/24/2012] [Indexed: 12/23/2022] Open
Abstract
Microbial biocatalysts such as Escherichia coli and Saccharomyces cerevisiae have been extensively subjected to Metabolic Engineering for the fermentative production of biorenewable fuels and chemicals. This often entails the introduction of new enzymes, deletion of unwanted enzymes and efforts to fine-tune enzyme abundance in order to attain the desired strain performance. Enzyme performance can be quantitatively described in terms of the Michaelis-Menten type parameters Km, turnover number kcat and Ki, which roughly describe the affinity of an enzyme for its substrate, the speed of a reaction and the enzyme sensitivity to inhibition by regulatory molecules. Here we describe examples of where knowledge of these parameters have been used to select, evolve or engineer enzymes for the desired performance and enabled increased production of biorenewable fuels and chemicals. Examples include production of ethanol, isobutanol, 1-butanol and tyrosine and furfural tolerance. The Michaelis-Menten parameters can also be used to judge the cofactor dependence of enzymes and quantify their preference for NADH or NADPH. Similarly, enzymes can be selected, evolved or engineered for the preferred cofactor preference. Examples of exporter engineering and selection are also discussed in the context of production of malate, valine and limonene.
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Affiliation(s)
- Laura R Jarboe
- Chemical and Biological Engineering, Iowa State University, Ames, Iowa, USA ; Microbiology, Iowa State University, Ames, Iowa, USA
| | - Ping Liu
- Microbiology, Iowa State University, Ames, Iowa, USA
| | | | - Lonnie O Ingram
- Microbiology and Cell Science, University of Florida, Gainesville, Florida, USA
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Promoter swapping unveils the role of the Citrobacter rodentium CTS1 type VI secretion system in interbacterial competition. Appl Environ Microbiol 2012; 79:32-8. [PMID: 23064344 DOI: 10.1128/aem.02504-12] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The type VI secretion system (T6SS) is a versatile secretion machine dedicated to various functions in Gram-negative bacteria, including virulence toward eukaryotic cells and antibacterial activity. Activity of T6SS might be followed in vitro by the release of two proteins, Hcp and VgrG, in the culture supernatant. Citrobacter rodentium, a rodent pathogen, harbors two T6SS gene clusters, cts1 and cts2. Reporter fusion and Hcp release assays suggested that the CTS1 T6SS was not produced or not active. The cts1 locus is composed of two divergent operons. We therefore developed a new vector allowing us to swap the two divergent endogenous promoters by P(tac) and P(BAD) using the λ red recombination technology. Artificial induction of both promoters demonstrated that the CTS1 T6SS is functional as shown by the Hcp release assay and confers on C. rodentium a growth advantage in antibacterial competition experiments with Escherichia coli.
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Gu P, Yang F, Kang J, Wang Q, Qi Q. One-step of tryptophan attenuator inactivation and promoter swapping to improve the production of L-tryptophan in Escherichia coli. Microb Cell Fact 2012; 11:30. [PMID: 22380540 PMCID: PMC3311589 DOI: 10.1186/1475-2859-11-30] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 03/02/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND L-tryptophan is an aromatic amino acid widely used in the food, chemical and pharmaceutical industries. In Escherichia coli, L-tryptophan is synthesized from phosphoenolpyruvate and erythrose 4-phosphate by enzymes in the shikimate pathway and L-tryptophan branch pathway, while L-serine and phosphoribosylpyrophosphate are also involved in L-tryptophan synthesis. In order to construct a microbial strain for efficient L-tryptophan production from glucose, we developed a one step tryptophan attenuator inactivation and promoter swapping strategy for metabolic flux optimization after a base strain was obtained by overexpressing the tktA, mutated trpE and aroG genes and inactivating a series of competitive steps. RESULTS The engineered E. coli GPT1002 with tryptophan attenuator inactivation and tryptophan operon promoter substitution exhibited 1.67 ~ 9.29 times higher transcription of tryptophan operon genes than the control GPT1001. In addition, this strain accumulated 1.70 g l(-1) L-tryptophan after 36 h batch cultivation in 300-mL shake flask. Bioreactor fermentation experiments showed that GPT1002 could produce 10.15 g l(-1) L-tryptophan in 48 h. CONCLUSIONS The one step inactivating and promoter swapping is an efficient method for metabolic engineering. This method can also be applied in other bacteria.
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Affiliation(s)
- Pengfei Gu
- State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Jinan 250100, People's Republic of China
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Wei XX, Shi ZY, Li ZJ, Cai L, Wu Q, Chen GQ. A mini-Mu transposon-based method for multiple DNA fragment integration into bacterial genomes. Appl Microbiol Biotechnol 2010; 87:1533-41. [DOI: 10.1007/s00253-010-2674-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2010] [Revised: 05/10/2010] [Accepted: 05/10/2010] [Indexed: 10/19/2022]
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