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Filluelo O, Ferrando J, Picart P. Metabolic engineering of Bacillus subtilis toward the efficient and stable production of C 30-carotenoids. AMB Express 2023; 13:38. [PMID: 37119332 PMCID: PMC10148934 DOI: 10.1186/s13568-023-01542-x] [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: 02/05/2023] [Accepted: 04/05/2023] [Indexed: 05/01/2023] Open
Abstract
Commercial carotenoid production is dominated by chemical synthesis and plant extraction, both of which are unsustainable and can be detrimental to the environment. A promising alternative for the mass production of carotenoids from both an ecological and commercial perspective is microbial synthesis. To date, C30 carotenoid production in Bacillus subtilis has been achieved using plasmid systems for the overexpression of biosynthetic enzymes. In the present study, we employed a clustered regularly interspaced short palindromic repeat-Cas9 (CRISPR-Cas9) system to develop an efficient, safe, and stable C30 carotenoid-producing B. subtilis strain, devoid of plasmids and antibiotic selection markers. To this end, the expression levels of crtM (dehydrosqualene synthase) and crtN (dehydrosqualene desaturase) genes from Staphylococcus aureus were upregulated by the insertion of three gene copies into the chromosome of B. subtilis. Subsequently, the supply of the C30 carotenoid precursor farnesyl diphosphate (FPP), which is the substrate for CrtMN enzymes, was enhanced by expressing chromosomally integrated Bacillus megaterium-derived farnesyl diphosphate synthase (FPPS), a key enzyme in the FPP pathway, and abolishing the expression of farnesyl diphosphate phosphatase (YisP), an enzyme responsible for the undesired conversion of FPP to farnesol. The consecutive combination of these features resulted in a stepwise increased production of C30 carotenoids. For the first time, a B. subtilis strain that can endogenously produce C30 carotenoids has been constructed, which we anticipate will serve as a chassis for further metabolic engineering and fermentation optimization aimed at developing a commercial scale bioproduction process.
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Affiliation(s)
- Oriana Filluelo
- Faculty of Pharmacy and Food Science Technology, Department of Biology, Healthcare and the Environment, Microbiology Section, University of Barcelona, Avinguda Joan XXIII, 27-31, Barcelona, 08028, Spain
| | - Jordi Ferrando
- Faculty of Pharmacy and Food Science Technology, Department of Biology, Healthcare and the Environment, Microbiology Section, University of Barcelona, Avinguda Joan XXIII, 27-31, Barcelona, 08028, Spain
| | - Pere Picart
- Faculty of Pharmacy and Food Science Technology, Department of Biology, Healthcare and the Environment, Microbiology Section, University of Barcelona, Avinguda Joan XXIII, 27-31, Barcelona, 08028, Spain.
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Zhang G, Lin M, Qin M, Xie Q, Liang M, Jiang J, Dai H, Xu S, Feng S, Liao M. Establishing Heterologous Production of Microcins J25 and Y in Bacillus subtilis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:5600-5613. [PMID: 36995900 DOI: 10.1021/acs.jafc.3c00675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Microcin J25 (MccJ25) and microcin Y (MccY) are lasso peptides and considered potential alternatives to antibiotics and harmful preservatives. The combination of these two microcins can provide a wide antimicrobial spectrum against food-borne Salmonella. Currently, MccJ25 and MccY are produced using Escherichia coli expression systems; however, the entire production process is accompanied by negative effects from endotoxins. In this study, we identified Bacillus subtilis as a suitable host for MccJ25 and MccY production. High-level production of microcins was achieved by promoter optimization, host strain selection, and recombinant expression. The engineered strains produced maximum yields of 2.827 μM MccJ25 and 1.481 μM MccY. This is the first study to demonstrate the expression of MccJ25 and MccY in B. subtilis, and it offers a few engineered strains that are without antibiotic resistance markers, inducer-free, sporulation-deficient, and free of the negative effects of endotoxins for antibacterial therapy and food preservation.
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Affiliation(s)
- Guangwen Zhang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Min Lin
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Miaomiao Qin
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Qianmei Xie
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Mingzhi Liang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Jinfei Jiang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Huilin Dai
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Siqi Xu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
| | - Saixiang Feng
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, P. R. China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, P. R. China
- Key Laboratory of Veterinary Vaccine Innovation of the Ministry of Agriculture, Guangzhou 510642, P. R. China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, Guangzhou 510642, P. R. China
| | - Ming Liao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P. R. China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, P. R. China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, P. R. China
- Key Laboratory of Veterinary Vaccine Innovation of the Ministry of Agriculture, Guangzhou 510642, P. R. China
- National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, Guangzhou 510642, P. R. China
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Chu PTB, Phan TTP, Nguyen TTT, Truong TTT, Schumann W, Nguyen HD. Potent IPTG-inducible integrative expression vectors for production of recombinant proteins in Bacillus subtilis. World J Microbiol Biotechnol 2023; 39:143. [PMID: 37004690 DOI: 10.1007/s11274-023-03566-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 03/03/2023] [Indexed: 04/04/2023]
Abstract
The IPTG-inducible promoter family, Pgrac, allows high protein expression levels in an inducible manner. In this study, we constructed IPTG-inducible expression vectors containing strong Pgrac promoters that allow integration of the transgene at either the amyE or lacA locus or both loci in Bacillus subtilis. Our novel integrative expression vectors based on Pgrac promoters could control the repression of protein production in the absence and the induction in the presence of an inducer, IPTG. The β-galactosidase (BgaB) protein levels were 9.0%, 15% and 30% of the total cellular protein in the B. subtilis strains carrying single cassettes with the Pgrac01, Pgrac100 or Pgrac212 promoters, respectively. The maximal induction ratio of Pgrac01-bgaB was 35.5 while that of Pgrac100-bgaB was 7.5 and that of Pgrac212-bgaB was 9. The inducible expression of GFP and BgaB protein was stably maintained for 24 h, with the highest yield of GFP being 24% of cell total protein while the maximum amount of BgaB was found to be 38%. A dual integration of two copies of the gfp+ gene into the B. subtilis genome at the lacA and amyE loci resulted in a yield of about 40% of total cellular protein and a 1.74-fold increase in GFP compared with single-integrated strains containing the same Pgrac212 promoter. The capability of protein production from low to high levels of these inducible integrative systems is useful for fundamental and applied research in B. subtilis.
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Affiliation(s)
- Phuong Thi Bich Chu
- Center for Bioscience and Biotechnology, University of Science, Ho Chi Minh City, Vietnam
- Vietnam National University, Ho Chi Minh City, Vietnam
- Faculty of Pharmacy, HUTECH University, Ho Chi Minh City, Vietnam
| | - Trang Thi Phuong Phan
- Center for Bioscience and Biotechnology, University of Science, Ho Chi Minh City, Vietnam.
- Vietnam National University, Ho Chi Minh City, Vietnam.
- Laboratory of Molecular Biotechnology, University of Science, Ho Chi Minh City, Vietnam.
| | - Tam Thi Thanh Nguyen
- Center for Bioscience and Biotechnology, University of Science, Ho Chi Minh City, Vietnam
- Vietnam National University, Ho Chi Minh City, Vietnam
- Faculty of Pharmacy, HUTECH University, Ho Chi Minh City, Vietnam
| | - Tuom Thi Tinh Truong
- Center for Bioscience and Biotechnology, University of Science, Ho Chi Minh City, Vietnam
- Vietnam National University, Ho Chi Minh City, Vietnam
- Cancer Research Laboratory, University of Science, Ho Chi Minh City, Vietnam
| | - Wolfgang Schumann
- Center for Bioscience and Biotechnology, University of Science, Ho Chi Minh City, Vietnam
- Vietnam National University, Ho Chi Minh City, Vietnam
- Institute of Genetics, University of Bayreuth, 95440, Bayreuth, Germany
| | - Hoang Duc Nguyen
- Center for Bioscience and Biotechnology, University of Science, Ho Chi Minh City, Vietnam.
- Vietnam National University, Ho Chi Minh City, Vietnam.
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Ferrando J, Filluelo O, Zeigler DR, Picart P. Barriers to simultaneous multilocus integration in Bacillus subtilis tumble down: development of a straightforward screening method for the colorimetric detection of one-step multiple gene insertion using the CRISPR-Cas9 system. Microb Cell Fact 2023; 22:21. [PMID: 36721198 PMCID: PMC9890709 DOI: 10.1186/s12934-023-02032-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Accepted: 01/25/2023] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Despite recent advances in genetic engineering tools for effectively regulating and manipulating genes, efficient simultaneous multigene insertion methods have not been established in Bacillus subtilis. To date, multilocus integration systems in B. subtilis, which is one of the main industrial enzyme producers and a GRAS (generally regarded as safe) microbial host, rely on iterative rounds of plasmid construction for sequential insertions of genes into the B. subtilis chromosome, which is tedious and time consuming. RESULTS In this study, we present development and proof-of-concept of a novel CRISPR-Cas9-based genome-editing strategy for the colorimetric detection of one-step multiple gene insertion in B. subtilis. First, up to three copies of the crtMN operon from Staphylococcus aureus, encoding a yellow pigment, were incorporated at three ectopic sites within the B. subtilis chromosome, rendering engineered strains able to form yellow colonies. Second, a single CRISPR-Cas9-based plasmid carrying a highly specific single guide RNA (sgRNA) targeting crtMN operon and a changeable editing template was constructed to facilitate simultaneous insertion of multiple gene-copies through homology-directed repair (HDR). Upon transformation of engineered strains with engineered plasmids, strains harboring up to three gene copies integrated into the chromosome formed white colonies because of the removal of the crtMN operon, clearly distinguishable from yellow colonies harboring undesired genetic modifications. As a result, construction of a plasmid-less, marker-free, high-expression stable producer B. subtilis strain can be completed in only seven days, demonstrating the potential that the implementation of this technology may bring for biotechnology purposes. CONCLUSIONS The novel technology expands the genome-editing toolset for B. subtilis and means a substantial improvement over current methodology, offering new application possibilities that we envision should significantly boost the development of B. subtilis as a chassis in the field of synthetic biology.
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Affiliation(s)
- Jordi Ferrando
- grid.5841.80000 0004 1937 0247Microbiology Section, Department of Biology, Healthcare and Environment, Faculty of Pharmacy and Food Sciences, Universitat de Barcelona, Barcelona, Catalonia Spain
| | - Oriana Filluelo
- grid.5841.80000 0004 1937 0247Microbiology Section, Department of Biology, Healthcare and Environment, Faculty of Pharmacy and Food Sciences, Universitat de Barcelona, Barcelona, Catalonia Spain
| | | | - Pere Picart
- grid.5841.80000 0004 1937 0247Microbiology Section, Department of Biology, Healthcare and Environment, Faculty of Pharmacy and Food Sciences, Universitat de Barcelona, Barcelona, Catalonia Spain
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Yin M, Wang N, Wang Q, Xia H, Cheng X, Hu H, Zhang Z, Liu H. Cloning and expression of recombinant human superoxide dismutase 1 (hSOD1) in Bacillus subtilis 1012. Biotechnol Lett 2023; 45:125-135. [PMID: 36469194 DOI: 10.1007/s10529-022-03319-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 10/13/2022] [Accepted: 10/17/2022] [Indexed: 12/08/2022]
Abstract
OBJECTIVE We aimed to clone and express the human Cu, Zn superoxide dismutase (hSOD1) in Bacillus subtilis 1012. Also, we investigated the expression level of hSOD1 under different induction conditions. RESULT As an essential member of the antioxidant defense system in vivo, hSOD1 has become a therapeutic agent against host diseases, such as oxygen toxicity, acute inflammation, and radiation injury. The recombinant hSOD1 was successfully secreted extracellularly into B. subtilis 1012. The expression conditions were optimized, including inoculum size, different media, temperatures, and inducer concentrations. Finally, the highest level of hSOD1 was produced as a soluble form in Super rich medium by 2% inoculum with 0.2 mM of IPTG at 37 °C after the induction for 24 h. Besides, 20 g/L of lactose also displayed the same inductive effect on hSOD1 expression as that of IPTG (0.2 mM). Finally, the specific activity of purified hSOD1 was determined to be 1625 U/mg in the presence of 800 μM of Cu2+ and 20 μM of Zn2+. CONCLUSIONS We propose that the B. subtilis 1012-hSOD1 strain system has great potential in future industrial applications.
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Affiliation(s)
- Mingzhu Yin
- College of Basic Medical Sciences, Hubei University of Chinese Medicine, Huangjiahu West Road 16, Wuhan, 430065, People's Republic of China
| | - Nian Wang
- College of Basic Medical Sciences, Sun YAT-SEN University, No. 135, Xingang Xi Road, Guangzhou, 510275, People's Republic of China
| | - Qiqi Wang
- College of Basic Medical Sciences, Hubei University of Chinese Medicine, Huangjiahu West Road 16, Wuhan, 430065, People's Republic of China
| | - Hui Xia
- College of Basic Medical Sciences, Hubei University of Chinese Medicine, Huangjiahu West Road 16, Wuhan, 430065, People's Republic of China
| | - Xue Cheng
- College of Basic Medical Sciences, Hubei University of Chinese Medicine, Huangjiahu West Road 16, Wuhan, 430065, People's Republic of China
| | - Haiming Hu
- College of Basic Medical Sciences, Hubei University of Chinese Medicine, Huangjiahu West Road 16, Wuhan, 430065, People's Republic of China
| | - Zhigang Zhang
- College of Basic Medical Sciences, Hubei University of Chinese Medicine, Huangjiahu West Road 16, Wuhan, 430065, People's Republic of China.
| | - Hongtao Liu
- College of Basic Medical Sciences, Hubei University of Chinese Medicine, Huangjiahu West Road 16, Wuhan, 430065, People's Republic of China.
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Li M, Qin J, Xiong K, Jiang B, Zhang T. Review of arginase as a promising biocatalyst: characteristics, preparation, applications and future challenges. Crit Rev Biotechnol 2021; 42:651-667. [PMID: 34612104 DOI: 10.1080/07388551.2021.1947962] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
As a committed step in the urea cycle, arginase cleaves l-arginine to form l-ornithine and urea. l-Ornithine is essential to: cell proliferation, collagen formation and other physiological functions, while the urea cycle itself converts highly toxic ammonia to urea for excretion. Recently, arginase was exploited as an efficient catalyst for the environmentally friendly synthesis of l-ornithine, an abundant nonprotein amino acid that is widely employed as a food supplement and nutrition product. It was also proposed as an arginine-reducing agent in order to treat arginase deficiency and to be a means of depleting arginine to treat arginine auxotrophic tumors. Targeting arginase inhibitors of the arginase/ornithine pathway offers great promise as a therapy for: cardiovascular, central nervous system diseases and cancers with high arginase expression. In this review, recent advances in the characteristics, structure, catalytic mechanism and preparation of arginase were summarized, with a focus being placed on the biotechnical and medical applications of arginase. In particular, perspectives have been presented on the challenges and opportunities for the environmentally friendly utilization of arginase during l-ornithine production and in therapies.
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Affiliation(s)
- Mengli Li
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Jiufu Qin
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Kai Xiong
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Bo Jiang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, Jiangsu, China
| | - Tao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
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Yang H, Qu J, Zou W, Shen W, Chen X. An overview and future prospects of recombinant protein production in Bacillus subtilis. Appl Microbiol Biotechnol 2021; 105:6607-6626. [PMID: 34468804 DOI: 10.1007/s00253-021-11533-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 08/12/2021] [Accepted: 08/15/2021] [Indexed: 12/27/2022]
Abstract
Bacillus subtilis is a well-characterized Gram-positive bacterium and a valuable host for recombinant protein production because of its efficient secretion ability, high yield, and non-toxicity. Here, we comprehensively review the recent studies on recombinant protein production in B. subtilis to update and supplement other previous reviews. We have focused on several aspects, including optimization of B. subtilis strains, enhancement and regulation of expression, improvement of secretion level, surface display of proteins, and fermentation optimization. Among them, optimization of B. subtilis strains mainly involves undirected chemical/physical mutagenesis and selection and genetic manipulation; enhancement and regulation of expression comprises autonomous plasmid and integrated expression, promoter regulation and engineering, and fine-tuning gene expression based on proteases and molecular chaperones; improvement of secretion level predominantly involves secretion pathway and signal peptide screening and optimization; surface display of proteins includes surface display of proteins on spores or vegetative cells; and fermentation optimization incorporates medium optimization, process condition optimization, and feeding strategy optimization. Furthermore, we propose some novel methods and future challenges for recombinant protein production in B. subtilis.Key points• A comprehensive review on recombinant protein production in Bacillus subtilis.• Novel techniques facilitate recombinant protein expression and secretion.• Surface display of proteins has significant potential for different applications.
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Affiliation(s)
- Haiquan Yang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.
| | - Jinfeng Qu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Wei Zou
- College of Bioengineering, Sichuan University of Science & Engineering, Yibin, 644000, Sichuan, China
| | - Wei Shen
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Xianzhong Chen
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.
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Integrative expression vectors with P grac promoters for inducer-free overproduction of recombinant proteins in Bacillus subtilis. BIOTECHNOLOGY REPORTS (AMSTERDAM, NETHERLANDS) 2020; 28:e00540. [PMID: 33163371 PMCID: PMC7599426 DOI: 10.1016/j.btre.2020.e00540] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 09/28/2020] [Accepted: 10/08/2020] [Indexed: 11/27/2022]
Abstract
The new inducer-free integrative expression vectors could repress the reporter gene expression in the E. coli cloning strain, thereby facilitating the cloning step. The expression vectors carrying IPTG-inducible Pgrac promoters allow the production of the recombinant protein at high levels in B. subtilis in the absence of the inducer. The single-copy expression levels of integrative constructs, Pgrac01-bgaB, Pgrac100-bgaB, Pgrac212-bgaB could reach to % and 8%, 20.9 % and 42 % of total cellular proteins after 12 h incubation, respectively. The double integration of Pgrac212-bgaB into both amyE and lacA loci resulted in BgaB expression up to 53.4 %.
Inducer-free integrative vectors are often used to create B. subtilis strains for industrial purposes, but employing strong promoters to produce high levels of recombinant proteins in B. subtilis results in high leaky expression that can hamper cloning in Escherichia coli. To overcome the problem, we used strong IPTG-inducible Pgrac promoters harboring lac operators to construct inducer-free integrative vectors able to integrate into the B. subtilis genome at either the lacA or the amyE locus, or both and examined their ability to repress the β-galactosidase (bgaB) gene in E. coli and to overexpress BgaB in B. subtilis. The Pgrac01 vectors could repress bgaB expression about 24-fold in E. coli to low background levels. The integrated Pgrac01-bgaB constructs exhibited inducer-free expression and produced 8% of total cellular proteins, only 1.25 or 1.75 times less compared with their cognates as plasmids. The stronger promoters, Pgrac100-bgaB and Pgrac212-bgaB yielded 20.9 % and 42 % of total intracellular proteins after 12 h of incubation, respectively. Incorporation of the Pgrac212-bgaB into both amyE and lacA loci resulted in BgaB expression up to 53.4 %. In conclusion, integrative vectors containing the Pgrac promoter family have great potential for inducer-free overproduction of recombinant proteins in B. subtilis.
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Watzlawick H, Altenbuchner J. Multiple integration of the gene ganA into the Bacillus subtilis chromosome for enhanced β-galactosidase production using the CRISPR/Cas9 system. AMB Express 2019; 9:158. [PMID: 31571017 PMCID: PMC6768931 DOI: 10.1186/s13568-019-0884-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 09/21/2019] [Indexed: 01/18/2023] Open
Abstract
The ganA gene from Bacillus subtilis encoding a β-galactosidase for degradation of the galactomannan was integrated in different loci of the B. subtilis chromosome employing the CRISPR/Cas9 system. Hereby a total of five copies of ganA cassettes in which the ganA gene was fused with the glucitol-promoter were inserted in the recipient chromosome wherein hypothetical, sporulation and protease genes were deleted. The strain with five copies of ganA expression cassette showed a β-galactosidase activity similar to the one with the same gene on a pUB110 derived multi-copy plasmid and under the same regulatory control of the glucitol promoter and GutR activator. The production of β-galactosidase in the strain with the multi-copy plasmid decreased rapidly when growth was performed under induced conditions and without antibiotic selection. In contrast, the strain with the five copies of ganA in the chromosome produced β-galactosidase for at least 40 generations. This demonstrates that the CRISPR/Cas9 system is a valuable and easy tool for constructing stable producer strains. The bigger efforts that are needed for the multiple target gene integration into the chromosome compared to cloning in expression vectors were justified by the higher stability of the target genes and the lack of antibiotic resistance genes.
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Draft Genome Sequence of Rummeliibacillus sp. Strain TYF005, a Physiologically Recalcitrant Bacterium with High Ethanol and Salt Tolerance Isolated from Spoilage Vinegar. Microbiol Resour Announc 2019; 8:8/31/e00244-19. [PMID: 31371531 PMCID: PMC6675979 DOI: 10.1128/mra.00244-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rummeliibacillus sp. strain TYF005 is a thermophilic bacterium with high ethanol (8% vol/vol) and salt (13% wt/vol) tolerance that was isolated from spoilage vinegar. Here, we report the draft genome sequence of this strain, which has 117 scaffolds with a total genome size of 3.7 Mb and a 34.4% GC content.
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Kai H, Xiao G, Bo J, Sen L. Construction of a food-grade arginase expression system and its application in L-ornithine production with whole cell biocatalyst. Process Biochem 2018. [DOI: 10.1016/j.procbio.2018.07.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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