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Ji Y, Li J, Liang Y, Li L, Wang Y, Pi L, Xing P, Nomura CT, Chen S, Zhu C, Wang Q. Engineering the Tat-secretion pathway of Bacillus licheniformis for the secretion of cytoplasmic enzyme arginase. Appl Microbiol Biotechnol 2024; 108:89. [PMID: 38194145 DOI: 10.1007/s00253-023-12917-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 10/06/2023] [Accepted: 10/16/2023] [Indexed: 01/10/2024]
Abstract
The industrial bacterium Bacillus licheniformis has long been used as a microbial factory for the production of enzymes due to its ability to secrete copious amounts of native extracellular proteins and its generally regarded as safe (GRAS) status. However, most attempts to use B. licheniformis to produce heterologous and cytoplasmic enzymes primarily via the general secretory (Sec) pathway have had limited success. The twin-arginine transport (Tat) pathway offers a promising alternative for the extracellular export of Sec-incompatible proteins because it transports full, correctly folded proteins. However, compared to the Sec pathway, the yields of the Tat pathway have historically been too low for commercial use. To improve the export efficiency of the Tat pathway, we identified the optimal Tat-dependent signal peptides and increased the abundance of the Tat translocases, the signal peptidase (SPase), and the intracellular chaperones. These strategic modifications significantly improved the Tat-dependent secretion of the cytoplasmic enzyme arginase into the culture medium using B. licheniformis. The extracellular enzymatic activity of arginase showed a 5.2-fold increase after these modifications. Moreover, compared to the start strain B. licheniformis 0F3, the production of extracellular GFP was improved by 3.8 times using the strategic modified strain B. licheniformis 0F13, and the extracellular enzymatic activity of SOX had a 1.3-fold increase using the strain B. licheniformis 0F14. This Tat-based production chassis has the potential for enhanced production of Sec-incompatible enzymes, therefore expanding the capability of B. licheniformis as an efficient cellular factory for the production of high-value proteins. KEY POINTS: • Systematic genetic modification of Tat-pathway in B. licheniformis. • Significant enhancement of the secretion capacity of Tat pathway for delivery the cytoplasmic enzyme arginase. • A new platform for efficient extracellular production of Sec-incompatible enzymes.
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Affiliation(s)
- Yi Ji
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, 430062, People's Republic of China
| | - Junliang Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, 430062, People's Republic of China
| | - Yonglin Liang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, 430062, People's Republic of China
| | - Liang Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, 430062, People's Republic of China
| | - Yajun Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, 430062, People's Republic of China
| | - Li Pi
- Wuhan Grand Hoyo Co., Ltd, Wuhan, 430075, People's Republic of China
| | - Panpan Xing
- Wuhan Grand Hoyo Co., Ltd, Wuhan, 430075, People's Republic of China
| | - Christopher T Nomura
- Department of Biological Sciences, University of Idaho, 875 Perimeter Drive, Moscow, ID, 83844, USA
| | - Shouwen Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, 430062, People's Republic of China
| | - Chengjun Zhu
- Wuhan Grand Hoyo Co., Ltd, Wuhan, 430075, People's Republic of China.
| | - Qin Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, 430062, People's Republic of China.
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Ma X, Zou D, Ji A, Jiang C, Zhao Z, Ding X, Han Z, Bao P, Chen K, Ma A, Wei X. Identification of a Novel Chitinase from Bacillus paralicheniformis: Gene Mining, Sequence Analysis, and Enzymatic Characterization. Foods 2024; 13:1777. [PMID: 38891005 PMCID: PMC11171888 DOI: 10.3390/foods13111777] [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: 05/19/2024] [Revised: 05/27/2024] [Accepted: 06/04/2024] [Indexed: 06/20/2024] Open
Abstract
In this study, a novel strain for degrading chitin was identified as Bacillus paralicheniformis HL37, and the key chitinase CH1 was firstly mined through recombinant expression in Bacillus amyloliquefaciens HZ12. Subsequently, the sequence composition and catalytic mechanism of CH1 protein were analyzed. The molecular docking indicated that the triplet of Asp526, Asp528, and Glu530 was a catalytic active center. The enzymatic properties analysis revealed that the optimal reaction temperature and pH was 65 °C and 6.0, respectively. Especially, the chitinase activity showed no significant change below 55 °C and it could maintain over 60% activity after exposure to 85 °C for 30 min. Moreover, the optimal host strain and signal peptide were obtained to enhance the expression of chitinase CH1 significantly. As far as we know, it was the first time finding the highly efficient chitin-degrading enzymes in B. paralicheniformis, and detailed explanations were provided on the catalytic mechanism and enzymatic properties on CH1.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Xuetuan Wei
- State Key Laboratory of Agricultural Microbiology, College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (X.M.); (D.Z.); (A.J.); (C.J.); (Z.Z.); (X.D.); (Z.H.); (P.B.); (K.C.); (A.M.)
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Liu X, Lian M, Zhao M, Huang M. Advances in recombinant protease production: current state and perspectives. World J Microbiol Biotechnol 2024; 40:144. [PMID: 38532149 DOI: 10.1007/s11274-024-03957-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 03/13/2024] [Indexed: 03/28/2024]
Abstract
Proteases, enzymes that catalyze the hydrolysis of peptide bonds in proteins, are important in the food industry, biotechnology, and medical fields. With increasing demand for proteases, there is a growing emphasis on enhancing their expression and production through microbial systems. However, proteases' native hosts often fall short in high-level expression and compatibility with downstream applications. As a result, the recombinant production of proteases has become a significant focus, offering a solution to these challenges. This review presents an overview of the current state of protease production in prokaryotic and eukaryotic expression systems, highlighting key findings and trends. In prokaryotic systems, the Bacillus spp. is the predominant host for proteinase expression. Yeasts are commonly used in eukaryotic systems. Recent advancements in protease engineering over the past five years, including rational design and directed evolution, are also highlighted. By exploring the progress in both expression systems and engineering techniques, this review provides a detailed understanding of the current landscape of recombinant protease research and its prospects for future advancements.
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Affiliation(s)
- Xiufang Liu
- School of Food Science and Engineering, South China University of Technology, Guangzhou, 510641, China
- Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou, 510650, China
| | - Mulin Lian
- School of Food Science and Engineering, South China University of Technology, Guangzhou, 510641, China
- Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou, 510650, China
| | - Mouming Zhao
- School of Food Science and Engineering, South China University of Technology, Guangzhou, 510641, China
- Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou, 510650, China
| | - Mingtao Huang
- School of Food Science and Engineering, South China University of Technology, Guangzhou, 510641, China.
- Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou, 510650, China.
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Chen Q, Wang B, Pan L. Efficient expression of γ-glutamyl transpeptidase in Bacillus subtilis via CRISPR/Cas9n and its immobilization. Appl Microbiol Biotechnol 2024; 108:149. [PMID: 38240797 DOI: 10.1007/s00253-023-12889-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 10/17/2023] [Accepted: 10/24/2023] [Indexed: 01/23/2024]
Abstract
In this study, we successfully applied the strategy of combining tandem promoters and tandem signal peptides with overexpressing signal peptidase to efficiently express and produce γ-glutamyl peptidase (GGT) enzymes (BsGGT, BaGGT, and BlGGT) from Bacillus subtilis, Bacillus amyloliquefaciens, and Bacillus licheniformis in Bacillus subtilis ATCC6051Δ5. In order to avoid the problem of instability caused by duplicated strong promoters, we assembled tandem promoters of different homologous genes from different species. To achieve resistance marker-free enzyme in the food industry, we first removed the replication origin and corresponding resistance marker of Escherichia coli from the expression vector. The plasmid was then transformed into the B. subtilis host, and the Kan resistance gene in the expression plasmid was directly edited and silenced using the CRISPR/Cas9n-AID base editing system. As a result, a recombinant protein expression carrier without resistance markers was constructed, and the enzyme activity of the BlGGT strain during shake flask fermentation can reach 53.65 U/mL. The recombinant BlGGT was immobilized with epoxy resin and maintained 82.8% enzyme activity after repeated use for 10 times and 87.36% enzyme activity after storage at 4 °C for 2 months. The immobilized BlGGT enzyme was used for the continuous synthesis of theanine with a conversion rate of 65.38%. These results indicated that our approach was a promising solution for improving enzyme production efficiency and achieving safe production of enzyme preparations in the food industry. KEY POINTS: • Efficient expression of recombinant proteins by a combination of dual promoter and dual signal peptide. • Construction of small vectors without resistance markers in B. subtilis using CRISPR/Cas9n-AID editing system. • The process of immobilizing BlGGT with epoxy resin was optimized.
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Affiliation(s)
- Qianlin Chen
- School of Biology and Biological Engineering, Guangzhou Higher Education Mega Centre, South China University of Technology, Panyu District, Guangzhou, 510006, Guangdong, People's Republic of China
| | - Bin Wang
- School of Biology and Biological Engineering, Guangzhou Higher Education Mega Centre, South China University of Technology, Panyu District, Guangzhou, 510006, Guangdong, People's Republic of China
| | - Li Pan
- School of Biology and Biological Engineering, Guangzhou Higher Education Mega Centre, South China University of Technology, Panyu District, Guangzhou, 510006, Guangdong, People's Republic of China.
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Zhang Y, Hu J, Zhang Q, Cai D, Chen S, Wang Y. Enhancement of alkaline protease production in recombinant Bacillus licheniformis by response surface methodology. BIORESOUR BIOPROCESS 2023; 10:27. [PMID: 38647919 PMCID: PMC10991860 DOI: 10.1186/s40643-023-00641-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 03/03/2023] [Indexed: 04/25/2024] Open
Abstract
Alkaline protease is widely used in the food, detergent, and pharmaceutical industries because of its comparatively great hydrolysis ability and alkali tolerance. To improve the ability of the recombinant Bacillus licheniformis to produce alkaline protease, single-factor experiments and response surface methodology (RSM) were utilized to determine and develop optimal culture conditions. The results showed that three factors (corn starch content, soybean meal content, and initial medium pH) had significant effects on alkaline protease production (P < 0.05), as determined through the Plackett‒Burman design. The maximum enzyme activity was observed with an optimal medium composition by central composite design (CCD): corn starch, 92.3 g/L; soybean meal, 35.8 g/L; and initial medium pH, 9.58. Under these optimum conditions, the alkaline protease activity of strain BL10::aprE was 15,435.1 U/mL, 82% higher than that in the initial fermentation medium. To further investigate the application of the optimum fermentation medium, the overexpressed strain BL10::aprE/pHYaprE was cultured using the optimized medium to achieve an enzyme activity of 39,233.6 U/mL. The present study achieved the highest enzyme activity of alkaline protease by B. licheniformis at the shake-flask fermentation level, which has important application value for large-scale production.
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Affiliation(s)
- Ying Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O. Box 329, Shanghai, 20037, China
| | - Jingmin Hu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O. Box 329, Shanghai, 20037, China
| | - Qing Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering Environmental, Microbial Technology Center of Hubei Province College of Life Sciences, Hubei University, Wuhan, China
| | - Dongbo Cai
- State Key Laboratory of Biocatalysis and Enzyme Engineering Environmental, Microbial Technology Center of Hubei Province College of Life Sciences, Hubei University, Wuhan, China
| | - Shouwen Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering Environmental, Microbial Technology Center of Hubei Province College of Life Sciences, Hubei University, Wuhan, China
| | - Yonghong Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P.O. Box 329, Shanghai, 20037, China.
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Sheng Y, Yang J, Wang C, Sun X, Yan L. Microbial nattokinase: from synthesis to potential application. Food Funct 2023; 14:2568-2585. [PMID: 36857725 DOI: 10.1039/d2fo03389e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Nattokinase (NK) is an alkaline serine protease with strong thrombolytic activity produced by Bacillus spp. or Pseudomonas spp. It is a potential therapeutic agent for thrombotic diseases because of its safety, economy, and lack of side effects. Herein, a comprehensive summary and analysis of the reports surrounding NK were presented, and the physical-chemical properties and producers of NK were first described. The process and mechanism of NK synthesis were summarized, but these are vague and not specific enough. Further results may be achieved if detection techniques such as multi-omics are used to explore the process of NK synthesis. The purification of NK has problems such as a complicated operation and low recovery rate, which were found when summarizing the techniques to improve the quality of finished products. If multiple simple and efficient precipitation methods and purification materials are combined to purify NK, it may be possible to solve the current challenges. Additionally, the application potential of NK in biomedicine was reviewed, but functional foods with NK are challenging for acceptance in daily life due to their unpleasant odor. Accordingly, multi-strain combination fermentation or food flavoring agents can improve the odor of fermented foods and increase people's acceptance of them. Finally, the possible future directions focused on NK studies were proposed and provided suggestions for subsequent researchers.
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Affiliation(s)
- Yanan Sheng
- College of Food, Heilongjiang Bayi Agricultural University, Daqing 163319, PR China.
| | - Jiani Yang
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing 163319, PR China
| | - Changyuan Wang
- College of Food, Heilongjiang Bayi Agricultural University, Daqing 163319, PR China.
| | - Xindi Sun
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing 163319, PR China
| | - Lei Yan
- College of Food, Heilongjiang Bayi Agricultural University, Daqing 163319, PR China.
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing 163319, PR China
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7
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Liao Y, Xiong M, Miao Z, Ishaq AR, Zhang M, Li B, Zhan Y, Cai D, Yang Z, Chen J, Chen S. Modular Engineering to Enhance Keratinase Production for Biotransformation of Discarded Feathers. Appl Biochem Biotechnol 2023; 195:1752-1769. [PMID: 36394712 DOI: 10.1007/s12010-022-04206-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2022] [Indexed: 11/19/2022]
Abstract
Biotransformation of wasted feathers via feather-degrading enzyme has gained immense popularity, low conversion efficiency hinders its scale application, and the main purpose of this study is to improve feather-degrading enzyme production in Bacillus licheniformis. Firstly, keratinase from Bacillus amyloliquefaciens K11 was attained with the best performance for feather hydrolysis, via screening several extracellular proteases from Bacillus; also, feather powder was proven as the most suitable substrate for determination of feather-degrading enzyme activity. Then, expression elements, including signal peptides and promoters, were optimized, and the combination of signal peptide SPSacC with promoter Pdual3 owned the best performance, keratinase activity aggrandized by 6.21-fold. According to amino acid compositions of keratinase and feeding assays, Ala, Val, and Ser were proven as critical precursors, and strengthening these precursors' supplies via metabolic pathway optimization resulted in a 33.59% increase in the keratinase activity. Furthermore, keratinase activity reached 2210.66 U/mL, up to 56.74-fold from the original activity under the optimized fermentation condition in 3-L fermentor. Finally, the biotransformation process of discarded feathers by the fermented keratinase was optimized, and our results indicated that 90.94% of discarded feathers (16%, w/v) were decomposed in 12 h. Our results suggested that strengthening precursor amino acids' supplies was an efficient strategy for enhanced production of keratinase, and this research provided an efficient strain as well as the biotransformation process for discarded feather re-utilization.
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Affiliation(s)
- Yongqing Liao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Min Xiong
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Zhaoqi Miao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Ali Raza Ishaq
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Min Zhang
- Key Laboratory of Green Chemical Technology of Fujian Province University, College of Ecological and Resource Engineering, Wuyi University, Wuyishan, 354300, People's Republic of China
| | - Bichan Li
- Key Laboratory of Green Chemical Technology of Fujian Province University, College of Ecological and Resource Engineering, Wuyi University, Wuyishan, 354300, People's Republic of China
| | - Yangyang Zhan
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Dongbo Cai
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Zhifan Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Jun Chen
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, 430081, People's Republic of China.
| | - Shouwen Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China.
- Key Laboratory of Green Chemical Technology of Fujian Province University, College of Ecological and Resource Engineering, Wuyi University, Wuyishan, 354300, People's Republic of China.
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Modi A, Raval I, Doshi P, Joshi M, Joshi C, Patel AK. Heterologous expression of recombinant nattokinase in Escherichia coli BL21(DE3) and media optimization for overproduction of nattokinase using RSM. Protein Expr Purif 2023; 203:106198. [PMID: 36379347 DOI: 10.1016/j.pep.2022.106198] [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: 10/06/2022] [Revised: 11/02/2022] [Accepted: 11/02/2022] [Indexed: 11/14/2022]
Abstract
Nattokinase, a serine protease, was discovered in Bacillus subtilis during the fermentation of a soybean byproduct. Nattokinase is essential for the lysis of blood clots and the treatment of cardiac diseases including atherosclerosis, thrombosis, high blood pressure, and stroke. The demand for thrombolytic drugs rises as the prevalence of cardiovascular disease rises, and nattokinase is particularly effective for the treatment of cardiovascular diseases due to its long duration of action. In this study, we cloned the nattokinase gene from the Bacillus subtilis strain into the pET32a vector and expressed the protein in the E. coli BL21(DE3) strain. The active recombinant nattokinase was purified using Ni-NTA affinity chromatography and then evaluated for fibrinolytic and blood clot lysis activity. Physiological parameters for optimizing protein production at optimal pH, temperature, IPTG concentration, and incubation time were investigated. A statistical technique was used to optimize media components for nattokinase overproduction, and Central Composite Design-Response Surface Methodology-based optimization was used to select significant components for protein production. The optimized media produced 1805.50 mg/L of expressed nattokinase and 42.80 gm/L of bacterial mass. The fibrinolytic activity obtained from refolded native protein was 58FU/mg, which was five times higher than the available orokinase drug (11FU/mg). The efficiency with which a statistical technique for media optimization was implemented improved recombinant nattokinase production and provides new information for scale - up nattokinase toward industrial applications.
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Affiliation(s)
- Akhilesh Modi
- Gujarat Biotechnology Research Centre, Sector 11, Gandhinagar, 382010, Gujarat, India
| | - Ishan Raval
- Gujarat Biotechnology Research Centre, Sector 11, Gandhinagar, 382010, Gujarat, India
| | - Pooja Doshi
- Gujarat Biotechnology Research Centre, Sector 11, Gandhinagar, 382010, Gujarat, India
| | - Madhvi Joshi
- Gujarat Biotechnology Research Centre, Sector 11, Gandhinagar, 382010, Gujarat, India
| | - Chaitanya Joshi
- Gujarat Biotechnology Research Centre, Sector 11, Gandhinagar, 382010, Gujarat, India
| | - Amrutlal K Patel
- Gujarat Biotechnology Research Centre, Sector 11, Gandhinagar, 382010, Gujarat, India.
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The potential role of ischaemia-reperfusion injury in chronic, relapsing diseases such as rheumatoid arthritis, Long COVID, and ME/CFS: evidence, mechanisms, and therapeutic implications. Biochem J 2022; 479:1653-1708. [PMID: 36043493 PMCID: PMC9484810 DOI: 10.1042/bcj20220154] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 08/09/2022] [Accepted: 08/10/2022] [Indexed: 02/07/2023]
Abstract
Ischaemia–reperfusion (I–R) injury, initiated via bursts of reactive oxygen species produced during the reoxygenation phase following hypoxia, is well known in a variety of acute circumstances. We argue here that I–R injury also underpins elements of the pathology of a variety of chronic, inflammatory diseases, including rheumatoid arthritis, ME/CFS and, our chief focus and most proximally, Long COVID. Ischaemia may be initiated via fibrin amyloid microclot blockage of capillaries, for instance as exercise is started; reperfusion is a necessary corollary when it finishes. We rehearse the mechanistic evidence for these occurrences here, in terms of their manifestation as oxidative stress, hyperinflammation, mast cell activation, the production of marker metabolites and related activities. Such microclot-based phenomena can explain both the breathlessness/fatigue and the post-exertional malaise that may be observed in these conditions, as well as many other observables. The recognition of these processes implies, mechanistically, that therapeutic benefit is potentially to be had from antioxidants, from anti-inflammatories, from iron chelators, and via suitable, safe fibrinolytics, and/or anti-clotting agents. We review the considerable existing evidence that is consistent with this, and with the biochemical mechanisms involved.
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Yuan L, Liangqi C, Xiyu T, Jinyao L. Biotechnology, Bioengineering and Applications of Bacillus Nattokinase. Biomolecules 2022; 12:biom12070980. [PMID: 35883536 PMCID: PMC9312984 DOI: 10.3390/biom12070980] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/12/2022] [Accepted: 07/12/2022] [Indexed: 02/04/2023] Open
Abstract
Thrombosis has threatened human health in past decades. Bacillus nattokinase is a potential low-cost thrombolytic drug without side-effects and has been introduced into the consumer market as a functional food or dietary supplement. This review firstly summarizes the biodiversity of sources and the fermentation process of nattokinase, and systematically elucidates the structure, catalytic mechanism and enzymatic properties of nattokinase. In view of the problems of low fermentation yield, insufficient activity and stability of nattokinase, this review discusses the heterologous expression of nattokinase in different microbial hosts and summarizes the protein and genetic engineering progress of nattokinase-producing strains. Finally, this review summarizes the clinical applications of nattokinase.
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Affiliation(s)
- Li Yuan
- Department of Materia Medica, Xinjiang University, Urumqi 830017, China;
| | - Chen Liangqi
- Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, College of Life Science and Technology, Xinjiang University, Urumqi 830017, China; (C.L.); (T.X.)
| | - Tang Xiyu
- Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, College of Life Science and Technology, Xinjiang University, Urumqi 830017, China; (C.L.); (T.X.)
| | - Li Jinyao
- Department of Materia Medica, Xinjiang University, Urumqi 830017, China;
- Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, College of Life Science and Technology, Xinjiang University, Urumqi 830017, China; (C.L.); (T.X.)
- Correspondence: ; Tel.: +86-130-0968-6488
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11
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Construction Method of Industrial College in Vocational Colleges Based on Cluster Analysis Algorithm. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2022; 2022:3278395. [PMID: 35734772 PMCID: PMC9208966 DOI: 10.1155/2022/3278395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 05/14/2022] [Accepted: 05/18/2022] [Indexed: 12/02/2022]
Abstract
In the context of the combination of industry and education, the construction of industrial colleges in vocational colleges can drive the scientific development of specialty settings in colleges and universities, and promote the way for colleges to expand students' practical teaching under the teaching of theoretical knowledge, and it is also an effective way for students to stimulate their learning enthusiasm and innovation enthusiasm. Colleges and universities can increase the direction and characteristics of specialist settings in colleges while enhancing instructors' professional level through school-business collaboration, and growing measures of talent training in colleges and universities plays a significant guiding role. The way to set up industrial colleges in vocational colleges reflects the development characteristics of talent training mode in the new era, and it is also an effective way to meet the practical training of students and the actual needs of society. It is a new school running mode of transforming productivity, cooperation, and mutual benefit, which is very worthy of promotion and development. This paper analyzes the problems existing in the construction of industrial colleges in vocational colleges in China and finds out the corresponding solutions. A path method of industrial college construction in vocational colleges based on the cluster analysis algorithm is proposed. The validity of this model is verified by experiments, which lays a foundation for the construction of industrial colleges in vocational colleges.
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Recent Advances in Nattokinase-Enriched Fermented Soybean Foods: A Review. Foods 2022; 11:foods11131867. [PMID: 35804683 PMCID: PMC9265860 DOI: 10.3390/foods11131867] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/16/2022] [Accepted: 06/20/2022] [Indexed: 01/27/2023] Open
Abstract
With the dramatic increase in mortality of cardiovascular diseases (CVDs) caused by thrombus, this has sparked an interest in seeking more effective thrombolytic drugs or dietary nutriments. The dietary consumption of natto, a traditional Bacillus-fermented food (BFF), can reduce the risk of CVDs. Nattokinase (NK), a natural, safe, efficient and cost-effective thrombolytic enzyme, is the most bioactive ingredient in natto. NK has progressively been considered to have potentially beneficial cardiovascular effects. Microbial synthesis is a cost-effective method of producing NK. Bacillus spp. are the main production strains. While microbial synthesis of NK has been thoroughly explored, NK yield, activity and stability are the critical restrictions. Multiple optimization strategies are an attempt to tackle the current problems to meet commercial demands. We focus on the recent advances in NK, including fermented soybean foods, production strains, optimization strategies, extraction and purification, activity maintenance, biological functions, and safety assessment of NK. In addition, this review systematically discussed the challenges and prospects of NK in actual application. Due to the continuous exploration and rapid progress of NK, NK is expected to be a natural future alternative to CVDs.
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Chen W, Li L, Ye C, Zhao Z, Huang K, Zou D, Wei X. Efficient production of extracellular alkaline protease in Bacillus amyloliquefaciens by host strain construction. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113620] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Zhang Q, Chen Y, Gao L, Chen J, Ma X, Cai D, Wang D, Chen S. Enhanced production of poly-γ-glutamic acid via optimizing the expression cassette of Vitreoscilla hemoglobin in Bacillus licheniformis. Synth Syst Biotechnol 2022; 7:567-573. [PMID: 35155838 PMCID: PMC8801620 DOI: 10.1016/j.synbio.2022.01.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 01/18/2022] [Accepted: 01/19/2022] [Indexed: 01/16/2023] Open
Abstract
Poly-γ-glutamic acid (γ-PGA) is a natural polymer with various applications, and its high-viscosity hinders oxygen transmission and improvement of synthesis level. Vitreoscilla hemoglobin (VHB) has been introduced into various hosts as oxygen carrier, however, its expression strength and contact efficiency with oxygen hindered efficient oxygen transfer and metabolite synthesis. Here, we want to optimize the expression cassette of VHB for γ-PGA production. Firstly, our results implied that γ-PGA yields were enhanced when introducing twin-arginine translocation (Tat) signal peptides (SPYwbN, SPPhoD and SPTorA) into VHB expression cassette, and the best performance was attained by SPYwbN from Bacillus subtilis, the γ-PGA yield of which was 18.53% higher than that of control strain, and intracellular ATP content and oxygen transfer coefficient (KLa) were increased by 29.71% and 73.12%, respectively, indicating that VHB mediated by SPYwbN benefited oxygen transfer and ATP generation for γ-PGA synthesis. Furthermore, four promoters were screened, and Pvgb was proven as the more suitable promoter for VHB expression and γ-PGA synthesis, and γ-PGA yield of attaining strain WX/pPvgb-YwbN-Vgb was further increased to 40.59 g/L by 10.18%. Finally, WX/pPvgb-YwbN-Vgb was cultivated in 3 L fermentor for fed-batch fermentation, and 46.39 g/L γ-PGA was attained by glucose feeding, increased by 49.26% compared with the initial yield (31.01 g/L). Taken together, this study has attained an efficient VHB expression cassette for oxygen transfer and γ-PGA synthesis, which could also be applied in the production of other metabolites.
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Affiliation(s)
- Qing Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, Wuhan, 430062, PR China
| | - Yaozhong Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, Wuhan, 430062, PR China
| | - Lin Gao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, Wuhan, 430062, PR China
- Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, China
| | - Jian'gang Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, Wuhan, 430062, PR China
- Wuhan Junan Biotechnology Co. Ltd., Wuhan, China
| | - Xin Ma
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, Wuhan, 430062, PR China
| | - Dongbo Cai
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, Wuhan, 430062, PR China
| | - Dong Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, Wuhan, 430062, PR China
- Corresponding author. 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, PR China.
| | - Shouwen Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, Wuhan, 430062, PR China
- Corresponding author. 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, PR China.
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Sharma A, Balda S, Capalash N, Sharma P. Engineering multifunctional enzymes for agro-biomass utilization. BIORESOURCE TECHNOLOGY 2022; 347:126706. [PMID: 35033642 DOI: 10.1016/j.biortech.2022.126706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 01/07/2022] [Accepted: 01/08/2022] [Indexed: 06/14/2023]
Abstract
Lignocellulosic biomass is a plentiful renewable resource that can be converted into a wide range of high-value-added industrial products. However, the complexity of its structural integrity is one of the major constraints and requires combinations of different fibrolytic enzymes for the cost-effective, industrially and environmentally feasible transformation. An interesting approach is constructing multifunctional enzymes, either in a single polypeptide or by joining multiple domains with linkers and performing diverse reactions simultaneously, in a single host. The production of such chimera proteins multiplies the advantages of different enzymatic reactions in a single setup, in lesser time, at lower production cost and with desirable and improved catalytic activities. This review embodies the various domain-tailoring and extracellular secretion strategies, possible solutions to their challenges, and efforts to experimentally connect different catalytic activities in a single host, as well as their applications.
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Affiliation(s)
- Aarjoo Sharma
- Department of Microbiology, Panjab University, Chandigarh, India
| | - Sanjeev Balda
- Department of Microbiology, Panjab University, Chandigarh, India
| | - Neena Capalash
- Department of Biotechnology, Panjab University, Chandigarh, India
| | - Prince Sharma
- Department of Microbiology, Panjab University, Chandigarh, India.
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Zou D, Ye C, Min Y, Li L, Ruan L, Yang Z, Wei X. Production of a novel lycopene-rich soybean food by fermentation with Bacillus amyloliquefaciens. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2021.112551] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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17
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Li T, Zhan C, Guo G, Liu Z, Hao N, Ouyang P. Tofu processing wastewater as a low-cost substrate for high activity nattokinase production using Bacillus subtilis. BMC Biotechnol 2021; 21:57. [PMID: 34620130 PMCID: PMC8499530 DOI: 10.1186/s12896-021-00719-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 09/29/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Even though tofu is a traditional Chinese food loved by Asian people the wastewater generated during the production of tofu can pollute the environment, and the treatment of this generated wastewater can increase the operating cost of the plant. In this study, the production of nattokinase could be achieved by using the nitrogen source in tofu processing wastewater (TPW) instead of using the traditional nattokinase medium. This meets the need for the low-cost fermentation of nattokinase and at the same time addresses the environmental pollution concerns caused by the wastewater. Bacillus subtilis 13,932 is, a high yielding strain of nattokinase, which is stored in our laboratory. To increase the activity of nattokinase in the tofu process wastewater fermentation medium, the medium components and culture parameters were optimized. Nattokinase with high enzymatic activity was obtained in 7 L and 100 L bioreactors when TPW was used as the sole nitrogen source catalyzed by Bacillus subtilis. Such a result demonstrates that the production of nattokinase from TPW fermentation using B. subtilis can be implemented at an industrial level. RESULTS The peptide component in TPW is a crucial factor in the production of nattokinase. Box-Behnken design (BBD) experiments were designed to optimize various critical components, i.e., Glucose, TPW, MgSO4·7H2O, CaCl2, in nattokinase fermentation media. A maximum nattokinase activity was recorded at 37 °C, pH 7.0, 70 mL liquid medium, and 200 rpm. The highest nattokinase activities obtained from 7 to 100 L bioreactors were 8628.35 ± 113.87 IU/mL and 10,661.97 ± 72.47 IU/mL, respectively. CONCLUSIONS By replacing the nitrogen source in the original medium with TPW, there was an increase in the enzyme activity by 19.25% after optimizing the medium and culture parameters. According to the scale-up experiment from conical flasks to 100 L bioreactors, there was an increase in the activity of nattokinase by 47.89%.
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Affiliation(s)
- Tao Li
- College of Biotechnology and Pharmaceutical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816, China
| | - Chenyi Zhan
- College of Biotechnology and Pharmaceutical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816, China
| | - Gege Guo
- College of Biotechnology and Pharmaceutical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816, China
| | - Zhaoxing Liu
- College of Biotechnology and Pharmaceutical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816, China
| | - Ning Hao
- College of Biotechnology and Pharmaceutical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816, China.
| | - Pingkai Ouyang
- College of Biotechnology and Pharmaceutical Engineering, State Key Laboratory of Materials-Oriented Chemical Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, 211816, China
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18
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Yao D, Zhang K, Zhu X, Su L, Wu J. Enhanced extracellular α-amylase production in Brevibacillus choshinensis by optimizing extracellular degradation and folding environment. J Ind Microbiol Biotechnol 2021; 49:6380490. [PMID: 34601573 PMCID: PMC9113144 DOI: 10.1093/jimb/kuab061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 08/22/2021] [Indexed: 11/14/2022]
Abstract
A strategy for optimizing the extracellular degradation and folding environment of Brevibacillus choshinensis has been used to enhance the extracellular production of recombinant α-amylase. First, a gene (bcp) encoding an extracellular protease and another encoding an extracellular chaperone (prsC) were identified in the genome of B. choshinensis HPD31-SP3. Then, the effect of extracellular protein degradation on recombinant α-amylase production was investigated by establishing a CRISPR/Cas9n system to knock out bcp. The effect of extracellular folding capacity was investigated separately by coexpressing extracellular chaperones genes from different sources (prsA, prsC, prsL, prsQ) in B. choshinensis. The final recombinant strain (BCPPSQ), which coexpressed prsQ in a genetic background lacking bcp, produced an extracellular α-amylase activity of 6940.9 U/mL during shake-flask cultivation. This was 2.1-fold greater than that of the original strain BCWPS (3367.9 U/mL). Cultivation of BCPPSQ in a 3-L fermenter produced an extracellular α-amylase activity of 17 925.6 U/mL at 72 h, which was 7.6-fold greater than that of BCWPS (2358.1 U/mL). This strategy demonstrates its great potential in enhancing extracellular α-amylase production in B. choshinensis. What's more, this study provides a strategic reference for improving the extracellular production of other recombinant proteins in B. choshinensis.
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Affiliation(s)
- Dongbang Yao
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,School of Biotechnology and Key Laboratory of Industrial Biotechnology Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,International Joint Laboratory on Food Safety, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| | - Kang Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,School of Biotechnology and Key Laboratory of Industrial Biotechnology Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,International Joint Laboratory on Food Safety, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| | - Xuyang Zhu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,School of Biotechnology and Key Laboratory of Industrial Biotechnology Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,International Joint Laboratory on Food Safety, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| | - Lingqia Su
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,School of Biotechnology and Key Laboratory of Industrial Biotechnology Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,International Joint Laboratory on Food Safety, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| | - Jing Wu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,School of Biotechnology and Key Laboratory of Industrial Biotechnology Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.,International Joint Laboratory on Food Safety, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
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Heterologous expression of nattokinase from B. subtilis natto using Pichia pastoris GS115 and assessment of its thrombolytic activity. BMC Biotechnol 2021; 21:49. [PMID: 34372833 PMCID: PMC8353737 DOI: 10.1186/s12896-021-00708-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Accepted: 07/14/2021] [Indexed: 11/10/2022] Open
Abstract
Background Nattokinase is a fibrinolytic enzyme that has huge market value as a nutritional supplement for health promotion. In order to increase nattokinase yields, fermentation conditions, strains, cultivation media, and feeding strategies have been optimized. Nattokinase has been expressed using several heterologous expression systems. Pichia pastoris heterologous expression system was the alternative. Results This report aimed to express high levels of nattokinase from B. subtilis natto (NK-Bs) using a Pichia pastoris heterologous expression system and assess its fibrinolytic activity in vivo. Multicopy expression strains bearing 1–7 copies of the aprN gene were constructed. The expression level of the target protein reached a maximum at five copies of the target gene. However, multicopy expression strains were not stable in shake-flask or high-density fermentation, causing significant differences in the yield of the target protein among batches. Therefore, P. pastoris bearing a single copy of aprN was used in shake-flask and high-density fermentation. Target protein yield was 320 mg/L in shake-flask fermentation and approximately 9.5 g/L in high-density fermentation. The recombinant nattokinase showed high thermo- and pH-stability. The present study also demonstrated that recombinant NK-Bs had obvious thrombolytic activity. Conclusions This study suggests that the P. pastoris expression system is an ideal platform for the large-scale, low-cost preparation of nattokinase. Supplementary Information The online version contains supplementary material available at 10.1186/s12896-021-00708-4.
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Muras A, Romero M, Mayer C, Otero A. Biotechnological applications of Bacillus licheniformis. Crit Rev Biotechnol 2021; 41:609-627. [PMID: 33593221 DOI: 10.1080/07388551.2021.1873239] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Bacillus licheniformis is a Gram positive spore-forming bacterial species of high biotechnological interest with numerous present and potential uses, including the production of bioactive compounds that are applied in a wide range of fields, such as aquaculture, agriculture, food, biomedicine, and pharmaceutical industries. Its use as an expression vector for the production of enzymes and other bioproducts is also gaining interest due to the availability of novel genetic manipulation tools. Furthermore, besides its widespread use as a probiotic, other biotechnological applications of B. licheniformis strains include: bioflocculation, biomineralization, biofuel production, bioremediation, and anti-biofilm activity. Although authorities have approved the use of B. licheniformis as a feed additive worldwide due to the absence of toxigenic potential, some probiotics containing this bacterium are considered unsafe due to the possible transference of antibiotic resistance genes. The wide variability in biological activities and genetic characteristics of this species makes it necessary to establish an exact protocol for describing the novel strains, in order to evaluate its biotechnological potential.
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Affiliation(s)
- Andrea Muras
- Departmento de Microbioloxía e Parasitoloxía, Facultade de Bioloxía-CIBUS, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Manuel Romero
- School of Life Sciences, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Celia Mayer
- Departmento de Microbioloxía e Parasitoloxía, Facultade de Bioloxía-CIBUS, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Ana Otero
- Departmento de Microbioloxía e Parasitoloxía, Facultade de Bioloxía-CIBUS, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
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21
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Zou D, Li L, Min Y, Ji A, Liu Y, Wei X, Wang J, Wen Z. Biosynthesis of a Novel Bioactive Metabolite of Spermidine from Bacillus amyloliquefaciens: Gene Mining, Sequence Analysis, and Combined Expression. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:267-274. [PMID: 33356220 DOI: 10.1021/acs.jafc.0c07143] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Spermidine is a biologically active polyamine with extensive application potential in functional foods. However, previously reported spermidine titers by biosynthesis methods are relatively low, which hinders its industrial application. To improve the spermidine titer, key genes affecting the spermidine production were mined to modify Bacillus amyloliquefaciens. Genes of S-adenosylmethionine decarboxylase (speD) and spermidine synthase (speE) from different microorganisms were expressed and compared in B. amyloliquefaciens. Therein, the speD from Escherichia coli and speE from Saccharomyces cerevisiae were confirmed to be optimal for spermidine synthesis, respectively. Gene and amino acid sequence analysis further confirmed the function of speD and speE. Then, these two genes were co-expressed to generate a recombinant strain B. amyloliquefaciens HSAM2(PDspeD-SspeE) with a spermidine titer of 105.2 mg/L, improving by 11.0-fold compared with the control (HSAM2). Through optimization of the fermentation medium, the spermidine titer was increased to 227.4 mg/L, which was the highest titer among present reports. Moreover, the consumption of the substrate S-adenosylmethionine was consistent with the accumulation of spermidine, which contributed to understanding its synthesis pattern. In conclusion, two critical genes for spermidine synthesis were obtained, and an engineering B. amyloliquefaciens strain was constructed for enhanced spermidine production.
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Affiliation(s)
- Dian Zou
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Lu Li
- Guangdong Key Laboratory of Agricultural Products Processing, Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510610, China
| | - Yu Min
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Anying Ji
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yingli Liu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing 100048, China
| | - Xuetuan Wei
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Jing Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing 100048, China
| | - Zhiyou Wen
- Department of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011, United States
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Food-grade expression of nattokinase in Lactobacillus delbrueckii subsp. bulgaricus and its thrombolytic activity in vitro. Biotechnol Lett 2020; 42:2179-2187. [PMID: 32705453 DOI: 10.1007/s10529-020-02974-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Accepted: 07/16/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVES To produce nattokinase in a food-grade expression system and evaluate its thrombolytic activity in vitro. RESULTS No nattokinase activity from reconstituted strains was observed in simulated gastric juice, but the enzyme was stable in intestinal fluid, the relative activity of which was found to be 60% after 4 h. Due to the nattokinase being produced intracellularly by recombinant bacterial strains, the persistence of the bacteria in gastric juice ensured transmission of the nattokinase into intestinal juice. Because of subsequent disintegration of the bacteria, the highest nattokinase activity was observed after 3 h at approximately 32%, following its carriage within the recombinant strains to the intestinal fluid. CONCLUSIONS This study demonstrated that nattokinase from recombinant strains exhibited good thrombolytic activity in vitro and may be used by the dairy fermentation industry for the development of novel thrombolytic functional foods.
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Xiao J, Peng B, Su Z, Liu A, Hu Y, Nomura CT, Chen S, Wang Q. Facilitating Protein Expression with Portable 5'-UTR Secondary Structures in Bacillus licheniformis. ACS Synth Biol 2020; 9:1051-1058. [PMID: 32302094 DOI: 10.1021/acssynbio.9b00355] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The 5'-untranslated region (5'-UTR) of prokaryotic mRNAs plays an essential role in post-transcriptional regulation. Bacillus species, such as Bacillus subtilis and Bacillus licheniformis, have gained considerable attention as microbial cell factories for the production of various valuable chemicals and industrial proteins. In this work, we developed a portable 5'-UTR sequence for enhanced protein output in the industrial strain B. licheniformis DW2. This sequence contains only ∼30 nt and forms a hairpin structure located right before the open reading frame. The optimized Shine-Dalgarno (SD) sequence was presented as a single strand on the loop of the hairpin for better ribosome recognition and recruitment. By optimizing the free energy of folding, this 5'-element could effectively enhance the expression of eGFP by ∼50-fold and showed good adaptability for other target proteins, including RFP, nattokinase, and keratinase. This 5'-UTR could promote the accessibility of both the SD sequence and start codon, leading to improved efficiency of translation initiation. Furthermore, the hairpin structure protected mRNA against 5'-exonucleases, resulting in enhanced mRNA stability. It is well-known that the stable structure at a ribosome binding site (RBS) impedes initiation in Escherichia coli. In this study, we presented a unique structure at a RBS that can effectively enhance protein production, which is an exception of this prevailing concept. By adjusting a single thermodynamic parameter and holding the other factors affecting protein output constant, a series of 5'-UTR elements with different expression strengths could be rationally designed for wide use in Bacillus sp.
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Affiliation(s)
- Jun Xiao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
| | - Bing Peng
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Zhaowei Su
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
| | - Ankun Liu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
| | - Yajing Hu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
| | - Christopher T. Nomura
- Department of Chemistry, The State University of New York College of Environmental Science and Forestry (SUNY-ESF), Syracuse, New York 13210, United States
| | - Shouwen Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
| | - Qin Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, Hubei University, Wuhan 430062, PR China
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Construction and application of a dual promoter system for efficient protein production and metabolic pathway enhancement in Bacillus licheniformis. J Biotechnol 2020; 312:1-10. [DOI: 10.1016/j.jbiotec.2020.02.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 02/20/2020] [Accepted: 02/28/2020] [Indexed: 12/31/2022]
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25
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Zou D, Min Y, Liu Y, Wei X, Wang J. Identification of a Spermidine Synthase Gene from Soybean by Recombinant Expression, Transcriptional Verification, and Sequence Analysis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:2366-2372. [PMID: 32017555 DOI: 10.1021/acs.jafc.9b07443] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Spermidine possesses multiple healthy functions, and soybeans contain the most abundant spermidine. In this study, spermidine contents of soybeans from different varieties and production regions in China were evaluated, and a spermidine synthase gene (speE) was identified by recombinant expression, transcriptional verification, and sequence analysis. Spermidine contents of soybean samples from 18 varieties ranged 72.38-228.82 mg/kg, and those from 19 production regions ranged 134.64-242.32 mg/kg. The highest-spermidine sample GZ was used to clone four predicted speE genes. Expressing the gene speE5 improved the spermidine titer by 54% in Bacillus amyloliquefaciens, confirming that speE5 was involved in spermidine synthesis. Transcriptional verification was performed through a soybean germination model. Germination for 48 h led to a onefold increase of spermidine in samples SHX and HB, and corresponding speE5 transcriptional levels were improved by 26-fold and 18-fold, respectively, further verifying the function of speE5. Finally, the sequences of the speE5 gene and deduced amino acids were analyzed, and the conserved sites and catalysis mechanisms were presented. This study identified an active spermidine synthase gene from soybean for the first time, which provided an important gene resource for genetic breeding of spermidine-rich soybean or microbial cell factory.
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Affiliation(s)
- Dian Zou
- Beijing Advanced Innovation Center for Food Nutrition and Human Health , Beijing Technology and Business University (BTBU) , Beijing 100048 , China
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology , Huazhong Agricultural University , Wuhan 430070 , China
| | - Yu Min
- Beijing Advanced Innovation Center for Food Nutrition and Human Health , Beijing Technology and Business University (BTBU) , Beijing 100048 , China
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology , Huazhong Agricultural University , Wuhan 430070 , China
| | - Yingli Liu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health , Beijing Technology and Business University (BTBU) , Beijing 100048 , China
| | - Xuetuan Wei
- Beijing Advanced Innovation Center for Food Nutrition and Human Health , Beijing Technology and Business University (BTBU) , Beijing 100048 , China
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology , Huazhong Agricultural University , Wuhan 430070 , China
| | - Jing Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health , Beijing Technology and Business University (BTBU) , Beijing 100048 , China
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Mo F, Cai D, He P, Yang F, Chen Y, Ma X, Chen S. Enhanced production of heterologous proteins via engineering the cell surface of Bacillus licheniformis. ACTA ACUST UNITED AC 2019; 46:1745-1755. [DOI: 10.1007/s10295-019-02229-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Accepted: 08/12/2019] [Indexed: 10/26/2022]
Abstract
Abstract
Cell surface engineering was proven as the efficient strategy for enhanced production of target metabolites. In this study, we want to improve the yield of target protein by engineering cell surface in Bacillus licheniformis. First, our results confirmed that deletions of d-alanyl-lipoteichoic acid synthetase gene dltD, cardiolipin synthase gene clsA and CDP-diacylglycerol-serine O-phosphatidyltransferase gene pssA were not conducive to cell growth, and the biomass of gene deletion strains were, respectively, decreased by 10.54 ± 1.43%, 14.17 ± 1.51%, and 17.55 ± 1.28%, while the concentrations of total extracellular proteins were improved, due to the increases of cell surface net negative charge and cell membrane permeability. In addition, the activities of target proteins, nattokinase, and α-amylase were also improved significantly in gene deletion strains. Furthermore, the triplicate gene (dltD, clsA, and pssA) deletion strain was constructed, which further led to the 45.71 ± 2.43% increase of cell surface net negative charge and 26.45 ± 2.31% increase of cell membrane permeability, and the activities of nattokinase and α-amylase reached 37.15 ± 0.89 FU/mL and 305.3 ± 8.4 U/mL, increased by 46.09 ± 3.51% and 96.34 ± 7.24%, respectively. Taken together, our results confirmed that cell surface engineering via deleting dltD, clsA, and pssA is an efficient strategy for enhanced production of target proteins, and this research provided a promising host strain of B. licheniformis for efficient protein expression.
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Affiliation(s)
- Fei Mo
- grid.34418.3a 0000 0001 0727 9022 State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences Hubei University 368 Youyi Avenue, Wuchang District 430062 Wuhan Hubei People’s Republic of China
| | - Dongbo Cai
- grid.34418.3a 0000 0001 0727 9022 State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences Hubei University 368 Youyi Avenue, Wuchang District 430062 Wuhan Hubei People’s Republic of China
| | - Penghui He
- grid.34418.3a 0000 0001 0727 9022 State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences Hubei University 368 Youyi Avenue, Wuchang District 430062 Wuhan Hubei People’s Republic of China
| | - Fan Yang
- grid.34418.3a 0000 0001 0727 9022 State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences Hubei University 368 Youyi Avenue, Wuchang District 430062 Wuhan Hubei People’s Republic of China
| | - Yaozhong Chen
- grid.34418.3a 0000 0001 0727 9022 State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences Hubei University 368 Youyi Avenue, Wuchang District 430062 Wuhan Hubei People’s Republic of China
| | - Xin Ma
- grid.34418.3a 0000 0001 0727 9022 State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences Hubei University 368 Youyi Avenue, Wuchang District 430062 Wuhan Hubei People’s Republic of China
| | - Shouwen Chen
- grid.34418.3a 0000 0001 0727 9022 State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences Hubei University 368 Youyi Avenue, Wuchang District 430062 Wuhan Hubei People’s Republic of China
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Transcriptional Changes in the Xylose Operon in Bacillus licheniformis and Their Use in Fermentation Optimization. Int J Mol Sci 2019; 20:ijms20184615. [PMID: 31540366 PMCID: PMC6769896 DOI: 10.3390/ijms20184615] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 09/14/2019] [Accepted: 09/16/2019] [Indexed: 12/18/2022] Open
Abstract
The xylose operon is an efficient biological element used for the regulation of gene expression in Bacillus licheniformis. Although the mechanism underlying the xylose-mediated regulation of this operon has been elucidated, the transcriptional changes that occur under various fermentation conditions remain unclear. In this study, the effects of different conditions on xylose operon expression were investigated. Significant upregulation was observed during the transition from the logarithmic phase to the stationary phase (2.5-fold, n = 3, p < 0.01). Glucose suppressed transcription over 168-fold (n = 3, p < 0.01). Meanwhile, the inhibitory effect of glucose hardly strengthened at concentrations from 20 to 180 g/L. Furthermore, the transcription of the xylose operon increased at elevated temperatures (25-42 °C) and was optimal at a neutral pH (pH 6.5-7.0). Based on these findings, relevant fermentation strategies (delaying the induction time, using dextrin as a carbon source, increasing the fermentation temperature, and maintaining a neutral pH) were proposed. Subsequently, these strategies were validated through the use of maltogenic amylase as a reporter protein, as an 8-fold (n = 3, p < 0.01) increase in recombinant enzyme activity compared to that under unoptimized conditions was observed. This work contributes to the development of fermentation optimization and furthers the use of the xylose operon as an efficient expression element.
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Ruan L, Li L, Zou D, Jiang C, Wen Z, Chen S, Deng Y, Wei X. Metabolic engineering of Bacillus amyloliquefaciens for enhanced production of S-adenosylmethionine by coupling of an engineered S-adenosylmethionine pathway and the tricarboxylic acid cycle. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:211. [PMID: 31516550 PMCID: PMC6732833 DOI: 10.1186/s13068-019-1554-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Accepted: 08/31/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND S-Adenosylmethionine (SAM) is a critical cofactor involved in many biochemical reactions. However, the low fermentation titer of SAM in methionine-free medium hampers commercial-scale production. The SAM synthesis pathway is specially related to the tricarboxylic acid (TCA) cycle in Bacillus amyloliquefaciens. Therefore, the SAM synthesis pathway was engineered and coupled with the TCA cycle in B. amyloliquefaciens to improve SAM production in methionine-free medium. RESULTS Four genes were found to significantly affect SAM production, including SAM2 from Saccharomyces cerevisiae, metA and metB from Escherichia coli, and native mccA. These four genes were combined to engineer the SAM pathway, resulting in a 1.42-fold increase in SAM titer using recombinant strain HSAM1. The engineered SAM pathway was subsequently coupled with the TCA cycle through deletion of succinyl-CoA synthetase gene sucC, and the resulted HSAM2 mutant produced a maximum SAM titer of 107.47 mg/L, representing a 0.59-fold increase over HSAM1. Expression of SAM2 in this strain via a recombinant plasmid resulted in strain HSAM3 that produced 648.99 mg/L SAM following semi-continuous flask batch fermentation, a much higher yield than previously reported for methionine-free medium. CONCLUSIONS This study reports an efficient strategy for improving SAM production that can also be applied for generation of SAM cofactors supporting group transfer reactions, which could benefit metabolic engineering, chemical biology and synthetic biology.
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Affiliation(s)
- Liying Ruan
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070 China
| | - Lu Li
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070 China
| | - Dian Zou
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070 China
| | - Cong Jiang
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070 China
| | - Zhiyou Wen
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070 China
- Department of Food Science and Human Nutrition, Iowa State University, Ames, 50011 USA
| | - Shouwen Chen
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Yu Deng
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), Jiangnan University, Wuxi, 214122 China
| | - Xuetuan Wei
- Key Laboratory of Environment Correlative Dietology (Ministry of Education), College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070 China
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Zhou C, Zhou H, Zhang H, Lu F. Optimization of alkaline protease production by rational deletion of sporulation related genes in Bacillus licheniformis. Microb Cell Fact 2019; 18:127. [PMID: 31345221 PMCID: PMC6657089 DOI: 10.1186/s12934-019-1174-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 07/17/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Our laboratory has constructed a Bacillus licheniformis strain that secretes alkaline protease (AprE) with excellent enzymatic properties. B. licheniformis is generally regarded as safe and has a high industrial exoenzyme secretion capacity, but the host retains some undomesticated characteristic that increase its competitiveness and survival, such as spore-formation, which increases the requirements and difficulties in industrial operations (e.g. sterilization and enzyme activity control). Furthermore, the influence of sporulation on alkaline protease production in B. licheniformis has not been elucidated in detail. RESULT A series of asporogenic variants of the parent strain were constructed by individually knocking out the master regulator genes (spo0A, sigF and sigE) involved in sporulation. Most of the variants formed abortively disporic cells characterized by asymmetric septa at the poles and unable to survive incubation at 75 °C for 10 min. Two of them (ΔsigF and ΔsigE) exhibited superior characteristics in protease production, especially improving the expression of the aprE gene. Under the currently used fermentation conditions, the vegetative production phase of ΔsigF can be prolonged to 72 h, and the highest protease production of ΔsigF reached 29,494 ± 1053 U/mL, which was about 19.7% higher than that of the wild-type strain. CONCLUSION We first constructed three key sporulation-deficient strain to investigate the effect of sporulation on alkaline protease synthesis. The sigF mutant retained important industrial properties such as facilitating the sterilization process, a prolonged stable phase of enzyme production and slower decreasing trend, which will be superior in energy conservation, simpler operations and target product controlling effect. In summary, the work provides a useful industrial host with preferable characteristics and a novel strategy to enhance the production of protease.
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Affiliation(s)
- Cuixia Zhou
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, No. 29, 13th Road, Tianjin Economic-Technological Development Area, Tianjin 022, 300457, People's Republic of China
| | - Huiying Zhou
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, No. 29, 13th Road, Tianjin Economic-Technological Development Area, Tianjin 022, 300457, People's Republic of China
| | - Huitu Zhang
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, No. 29, 13th Road, Tianjin Economic-Technological Development Area, Tianjin 022, 300457, People's Republic of China.
| | - Fuping Lu
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science & Technology, No. 29, 13th Road, Tianjin Economic-Technological Development Area, Tianjin 022, 300457, People's Republic of China.
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Ding Z, Guan F, Yu X, Li Q, Wang Q, Tian J, Wu N. Identification of the anchoring protein SpoIIIJ for construction of the microbial cell surface display system in Bacillus spp. Int J Biol Macromol 2019; 133:614-623. [DOI: 10.1016/j.ijbiomac.2019.04.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 02/28/2019] [Accepted: 04/05/2019] [Indexed: 01/16/2023]
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Expression of a Pseudomonas aeruginosa-targeted antimicrobial peptide T9W in Bacillus subtilis using a maltose-inducible vector. Process Biochem 2019. [DOI: 10.1016/j.procbio.2019.03.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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32
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Cai D, Zhang B, Rao Y, Li L, Zhu J, Li J, Ma X, Chen S. Improving the utilization rate of soybean meal for efficient production of bacitracin and heterologous proteins in the aprA-deficient strain of Bacillus licheniformis. Appl Microbiol Biotechnol 2019; 103:4789-4799. [PMID: 31025072 DOI: 10.1007/s00253-019-09804-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 03/20/2019] [Accepted: 03/27/2019] [Indexed: 12/17/2022]
Abstract
Soybean meal is commonly applied as the raw material in the bio-fermentation industry, and bacitracin is a widely used feed additive in the feed industry. In this study, we investigated the influence of subtilisin enhancement on soybean meal utilization and bacitracin production in Bacillus licheniformis DW2, an industrial strain for bacitracin production. Firstly, blocking sRNA aprA expression benefited bacitracin synthesis, and the bacitracin yield produced by aprA-deficient strain DW2△PaprA reached 931.43 U/mL, 18.92% higher than that of DW2 (783.25 U/mL). The bacitracin yield was reduced by 14.27% in the aprA overexpression strain. Furthermore, our results showed that deficiency of aprA led to a 6.54-fold increase of the aprE transcriptional level and a 1.84-fold increase of subtilisin activity, respectively, which led to the increases of soybean meal utilization rate (28.86%) and precursor amino acid supplies for bacitracin synthesis. Additionally, strengthening the utilization rate of soybean meal also benefited heterologous protein production, and the α-amylase and nattokinase activities were respectively enhanced by 59.81% and 50.53% in aprA-deficient strains. Collectively, this research demonstrated that strengthening subtilisin production could improve the utilization rate of soybean meal and thereby enhance bacitracin and target protein production; also, this strategy would be useful for the improvement of protein/peptide production using soybean meal as the main nitrogen source in the fermentation process.
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Affiliation(s)
- Dongbo Cai
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Bowen Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Yi Rao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Lingfeng Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Jiang Zhu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Junhui Li
- Lifecome Biochemistry Co. Ltd, Nanping, 353400, People's Republic of China
| | - Xin Ma
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Shouwen Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Sciences, Hubei University, 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China.
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Liu Z, Zheng W, Ge C, Cui W, Zhou L, Zhou Z. High-level extracellular production of recombinant nattokinase in Bacillus subtilis WB800 by multiple tandem promoters. BMC Microbiol 2019; 19:89. [PMID: 31064343 PMCID: PMC6505213 DOI: 10.1186/s12866-019-1461-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 04/18/2019] [Indexed: 01/24/2023] Open
Abstract
Background Nattokinase (NK), which is a member of the subtilisin family, is a potent fibrinolytic enzyme that might be useful for thrombosis therapy. Extensive work has been done to improve its production for the food industry. The aim of our study was to enhance NK production by tandem promoters in Bacillus subtilis WB800. Results Six recombinant strains harboring different plasmids with a single promoter (PP43, PHpaII, PBcaprE, PgsiB, PyxiE or PluxS) were constructed, and the analysis of the fibrinolytic activity showed that PP43 and PHpaII exhibited a higher expression activity than that of the others. The NK yield that was mediated by PP43 and PHpaII reached 140.5 ± 3.9 FU/ml and 110.8 ± 3.6 FU/ml, respectively. These promoters were arranged in tandem to enhance the expression level of NK, and our results indicated that the arrangement of promoters in tandem has intrinsic effects on the NK expression level. As the number of repetitive PP43 or PHpaII increased, the expression level of NK was enhanced up to the triple-promoter, but did not increase unconditionally. In addition, the repetitive core region of PP43 or PHpaII could effectively enhance NK production. Eight triple-promoters with PP43 and PHpaII in different orders were constructed, and the highest yield of NK finally reached 264.2 ± 7.0 FU/ml, which was mediated by the promoter PHpaII-PHpaII-PP43. The scale-up production of NK that was promoted by PHpaII-PHpaII-PP43 was also carried out in a 5-L fermenter, and the NK activity reached 816.7 ± 30.0 FU/mL. Conclusions Our studies demonstrated that NK was efficiently overproduced by tandem promoters in Bacillus subtilis. The highest fibrinolytic activity was promoted by PHpaII-PHpaII-PP43, which was much higher than that had been reported in previous studies. These multiple tandem promoters were used successfully to control NK expression and might be useful for improving the expression level of the other genes. Electronic supplementary material The online version of this article (10.1186/s12866-019-1461-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Zhongmei Liu
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China.
| | - Wenhui Zheng
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Chunlei Ge
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Wenjing Cui
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Li Zhou
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Zhemin Zhou
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China.
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Yan S, Wu G. Proteases HtrA and HtrB for α-amylase secreted from Bacillus subtilis in secretion stress. Cell Stress Chaperones 2019; 24:493-502. [PMID: 31001739 PMCID: PMC6527527 DOI: 10.1007/s12192-019-00985-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 02/22/2019] [Accepted: 02/25/2019] [Indexed: 01/16/2023] Open
Abstract
HtrA and HtrB are two important proteases across species. In biotechnological industries, they are related to degradation of secreted heterologous proteins from bacteria, especially in the case of overproduction of α-amylases in Bacillus subtilis. Induction of HtrA and HtrB synthesis follows the overproduction of α-amylases in B. subtilis. This is different from the order usually observed in B. subtilis, i.e., the production of proteases is prior to the secretion of proteins. This discrepancy suggests three possibilities: (i) HtrA and HtrB are constantly synthesized from the end of the exponential phase, and then are synthesized more abundantly due to secretion stress; (ii) There is a hysteresis mechanism that holds HtrA and HtrB back from their large amount of secretion before the overproduction of α-amylases; (iii) Heterologous amylases could be a stress to B. subtilis leading to a general response to stress. In this review, we analyze the literature to explore these three possibilities. The first possibility is attributed to the regulatory pathway of CssR-CssS. The second possibility is because sigma factor σD plays a role in the overproduction of α-amylases and is subpopulation dependent with the switch between "ON" and "OFF" states that is fundamental for a bistable system and a hysteresis mechanism. Thus, sigma factor σD helps to hold HtrA and HtrB back from massive secretion before the overproduction of α-amylases. The third possibility is that several sigma factors promote the secretion of proteases at the end of the exponential phase of growth under the condition that heterologous amylases are considered as a stress.
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Affiliation(s)
- Shaomin Yan
- State Key Laboratory of Non-Food Biomass and Enzyme Technology, National Engineering Research Center for Non-Food Biorefinery, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences, 98 Daling Road, Nanning, 530007, Guangxi, China
| | - Guang Wu
- State Key Laboratory of Non-Food Biomass and Enzyme Technology, National Engineering Research Center for Non-Food Biorefinery, Guangxi Key Laboratory of Bio-refinery, Guangxi Academy of Sciences, 98 Daling Road, Nanning, 530007, Guangxi, China.
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Li H, Ding Y, Zhao J, Ge R, Qiu B, Yang X, Yao L, Liu K, Wang C, Du B. Identification of a native promoter P LH-77 for gene expression in Paenibacillus polymyxa. J Biotechnol 2019; 295:19-27. [PMID: 30831123 DOI: 10.1016/j.jbiotec.2019.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 01/17/2019] [Accepted: 02/06/2019] [Indexed: 02/06/2023]
Abstract
Paenibacillus polymyxa is a rhizobacterium that has attracted substantial attention due to its ability to produce functional metabolites and promote plant growth. Metabolic and genetic improvements in this species will benefit research and other applications of the bacterium. However, a suitable gene expression system has not been established in this species. In this study, a promoter trap system based on a green fluorescent protein and a chloramphenicol-resistance gene was developed to isolate native promoters of P. polymyxa SC2-M1 to regulate gene expression. Through high-throughput screening, the novel promoter PLH-77 was identified, sequenced, and subsequently characterized. Promoter PLH-77 is a strong, continuous expression system containing the typical -10 and -35 motifs regions. Its effective sequence was evaluated and then cascaded to improve the promotion efficiency. To further verify the existence of PLH-77, a heterogenous xylose isomerase was expressed by PLH-77 in P. polymyxa SC2-M1. In the resulting strain, the amount of xylose consumed was increased by 2.5 g/L during the 78 h fermentation period. Meanwhile, the production levels of lactate and acetate increased. It was confirmed that promoter PLH-77 could effectively mediate gene expression in P. polymyxa SC2-M1 and will further benefit the quantitative monitoring of gene expression in P. polymyxa.
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Affiliation(s)
- Hui Li
- College of Life Sciences and Shandong Key Laboratory of Agricultural Microbiology and National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, 271018, China
| | - Yanqin Ding
- College of Life Sciences and Shandong Key Laboratory of Agricultural Microbiology and National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, 271018, China
| | - Jianzhi Zhao
- College of Bioengineering, Qilu University of Technology, Jinan, 250353, China
| | - Ruofei Ge
- College of Life Sciences and Shandong Key Laboratory of Agricultural Microbiology and National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, 271018, China
| | - Benhua Qiu
- College of Life Sciences and Shandong Key Laboratory of Agricultural Microbiology and National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, 271018, China
| | - Xiaoli Yang
- College of Life Sciences and Shandong Key Laboratory of Agricultural Microbiology and National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, 271018, China
| | - Liangtong Yao
- College of Life Sciences and Shandong Key Laboratory of Agricultural Microbiology and National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, 271018, China
| | - Kai Liu
- College of Life Sciences and Shandong Key Laboratory of Agricultural Microbiology and National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, 271018, China
| | - Chengqiang Wang
- College of Life Sciences and Shandong Key Laboratory of Agricultural Microbiology and National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, 271018, China.
| | - Binghai Du
- College of Life Sciences and Shandong Key Laboratory of Agricultural Microbiology and National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Shandong Agricultural University, Tai'an, 271018, China
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Zhou C, Liu H, Yuan F, Chai H, Wang H, Liu F, Li Y, Zhang H, Lu F. Development and application of a CRISPR/Cas9 system for Bacillus licheniformis genome editing. Int J Biol Macromol 2019; 122:329-337. [PMID: 30401651 DOI: 10.1016/j.ijbiomac.2018.10.170] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 10/24/2018] [Accepted: 10/25/2018] [Indexed: 10/28/2022]
Abstract
A highly efficient genome editing system for Bacillus licheniformis was developed based on single-plasmid CRISPR/Cas9. For highly efficient genome editing the shuttle vector pWH1520 was selected to construct the knockout plasmids. A construct harboring a pS promoter driving cas9 endonuclease expression, a strong pLY-2 promoter driving the transcription of a single guide RNA was demonstrated as being the most effective. To verify the feasibility of the method the uprT gene coding uracil phosphoribosyltransferase was selected as the reporter gene. The efficiency of introducing nucleotide point mutations and single gene deletion reached an editing efficiency of up to 99.2% and 97.3%, respectively. After a upp-deficient strain was engineered, the system and strain were applied to introduce genomic deletions of another two genes, amyL and chiA (encoding amylase and chitinase, respectively) with about 90% deletion efficiency. As two native extracellular proteins with relatively high secretion in the host, amylase and chitinase can hamper the secretion and expression of alkaline protease. It was demonstrated that the mutant with deletions of the two genes effectively improved the alkaline protease yield by 24.8%. The results illustrated that the establishment of a CRISPR/Cas9 system for Bacillus licheniformis is of significance, and confirmed the system's high efficiency. The system provides support for effective molecular modification and metabolic regulation of Bacillus licheniformis, and offers promise for applications in genetic modification of other industrially relevant Bacillus species.
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Affiliation(s)
- Cuixia Zhou
- State Key Laboratory of Food Nutrition and Safety, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 022, PR China
| | - Huan Liu
- State Key Laboratory of Food Nutrition and Safety, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 022, PR China
| | - Feiyan Yuan
- State Key Laboratory of Food Nutrition and Safety, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 022, PR China
| | - Haonan Chai
- State Key Laboratory of Food Nutrition and Safety, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 022, PR China
| | - Haikuan Wang
- State Key Laboratory of Food Nutrition and Safety, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 022, PR China
| | - Fufeng Liu
- State Key Laboratory of Food Nutrition and Safety, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 022, PR China
| | - Yu Li
- State Key Laboratory of Food Nutrition and Safety, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 022, PR China
| | - Huitu Zhang
- State Key Laboratory of Food Nutrition and Safety, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 022, PR China.
| | - Fuping Lu
- State Key Laboratory of Food Nutrition and Safety, College of Biotechnology, Tianjin University of Science &Technology, Tianjin 022, PR China.
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Cai D, Rao Y, Zhan Y, Wang Q, Chen S. EngineeringBacillusfor efficient production of heterologous protein: current progress, challenge and prospect. J Appl Microbiol 2019; 126:1632-1642. [DOI: 10.1111/jam.14192] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 12/13/2018] [Accepted: 12/28/2018] [Indexed: 12/18/2022]
Affiliation(s)
- D. Cai
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, College of Life Sciences, Hubei University Wuhan PR China
| | - Y. Rao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, College of Life Sciences, Hubei University Wuhan PR China
| | - Y. Zhan
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, College of Life Sciences, Hubei University Wuhan PR China
| | - Q. Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, College of Life Sciences, Hubei University Wuhan PR China
| | - S. Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province Hubei Collaborative Innovation Center for Green Transformation of Bio‐Resources, College of Life Sciences, Hubei University Wuhan PR China
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Development of Bacillus amyloliquefaciens as a high-level recombinant protein expression system. ACTA ACUST UNITED AC 2019; 46:113-123. [DOI: 10.1007/s10295-018-2089-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Accepted: 10/15/2018] [Indexed: 12/29/2022]
Abstract
Abstract
Bacillus amyloliquefaciens K11 is a hyperproducer of extracellular neutral protease, which can produce recombinant homologous protein steadily and is amenable to scale up to high-cell density fermentation. The present study aims to genetically modify strain K11 as a highly efficient secretory expression system for high-level production of heterologous proteins. Using B. amyloliquefaciens K11 and alkaline protease gene BcaprE as the expression host and model gene, the gene expression levels mediated by combinations of promoters PamyQ, PaprE and Pnpr and signal peptides SPamyQ, SPaprE and SPnpr were assessed on shake flask level. The PamyQ-SPaprE was found to be the best secretory expression cassette, giving the highest enzyme activities of extracellular BcaprE (13,800 ± 308 U/mL). Using the same expression system, the maltogenic α-amylase Gs-MAase and neutral protease BaNPR were successfully produced with the enzyme activities of 19. ± 0.2 U/mL and 17,495 ± 417 U/mL, respectively. After knocking out the endogenous neutral protease-encoding gene Banpr, the enzyme activities of BcaprE and Gs-MAase were further improved by 25.4% and 19.4%, respectively. Moreover, the enzyme activities of BcaprE were further improved to 30,200 ± 312 U/mL in a 15 L fermenter following optimization of the fermentation conditions. In the present study, the genetically engineered B. amyloliquefaciens strain 7-6 containing PamyQ-SPaprE as the secretory expression cassette was developed. This efficient expression system shows general applicability and represents an excellent industrial strain for the production of heterologous proteins.
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Liu X, Wang H, Wang B, Pan L. Efficient production of extracellular pullulanase in Bacillus subtilis ATCC6051 using the host strain construction and promoter optimization expression system. Microb Cell Fact 2018; 17:163. [PMID: 30348150 PMCID: PMC6196424 DOI: 10.1186/s12934-018-1011-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 10/15/2018] [Indexed: 12/21/2022] Open
Abstract
Background Bacillus subtilis has been widely used as a host for heterologous protein expression in food industry. B. subtilis ATCC6051 is an alternative expression host for the production of industrial enzymes, and exhibits favorable growth properties compared to B. subtilis 168. Extracellular expression of pullulanase from recombinant B. subtilis is still limited due to the issues on promoters of B. subtilis expression system. This study was undertaken to develop a new, high-level expression system in B. subtilis ATCC6051. Results To further optimize B. subtilis ATCC6051 as a expression host, eight extracellular proteases (aprE, nprE, nprB, epr, mpr, bpr, vpr and wprA), the sigma factor F (spoIIAC) and a surfactin (srfAC) were deleted, yielding the mutant B. subtilis ATCC6051∆10. ATCC6051∆10 showed rapid growth and produced much more extracellular protein compared to the widetype strain ATCC6051, due to the inactivation of multiple proteases. Using this mutant as the host, eleven plasmids equipped with single promoters were constructed for recombinant expression of pullulanase (PUL) from Bacillus naganoensis. The plasmid containing the PspovG promoter produced the highest extracellular PUL activity, which achieved 412.9 U/mL. Subsequently, sixteen dual-promoter plasmids were constructed and evaluated using this same method. The plasmid containing the dual promoter PamyL–PspovG produced the maximum extracellular PUL activity (625.5 U/mL) and showed the highest expression level (the dry cell weight of 18.7 g/L). Conclusions Taken together, we constructed an effective B. subtilis expression system by deleting multiple proteases and screening strong promoters. The dual-promoter PamyL–PspovG system was found to support superior expression of extracellular proteins in B. subtilis ATCC6051. Electronic supplementary material The online version of this article (10.1186/s12934-018-1011-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xin Liu
- School of Biology and Biological Engineering, Guangzhou Higher Education Mega Centre, South China University of Technology, Building B6, Panyu District, Guangzhou, 510006, Guangdong, People's Republic of China
| | - Hai Wang
- School of Biology and Biological Engineering, Guangzhou Higher Education Mega Centre, South China University of Technology, Building B6, Panyu District, Guangzhou, 510006, Guangdong, People's Republic of China
| | - Bin Wang
- School of Biology and Biological Engineering, Guangzhou Higher Education Mega Centre, South China University of Technology, Building B6, Panyu District, Guangzhou, 510006, Guangdong, People's Republic of China
| | - Li Pan
- School of Biology and Biological Engineering, Guangzhou Higher Education Mega Centre, South China University of Technology, Building B6, Panyu District, Guangzhou, 510006, Guangdong, People's Republic of China.
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Exploitation of Bacillus subtilis as a robust workhorse for production of heterologous proteins and beyond. World J Microbiol Biotechnol 2018; 34:145. [DOI: 10.1007/s11274-018-2531-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 09/05/2018] [Indexed: 10/28/2022]
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Chen Y, Cai D, He P, Mo F, Zhang Q, Ma X, Chen S. Enhanced production of heterologous proteins by Bacillus licheniformis with defective d-alanylation of lipoteichoic acid. World J Microbiol Biotechnol 2018; 34:135. [DOI: 10.1007/s11274-018-2520-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 08/16/2018] [Indexed: 11/25/2022]
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Cui W, Suo F, Cheng J, Han L, Hao W, Guo J, Zhou Z. Stepwise modifications of genetic parts reinforce the secretory production of nattokinase in Bacillus subtilis. Microb Biotechnol 2018; 11:930-942. [PMID: 29984489 PMCID: PMC6116739 DOI: 10.1111/1751-7915.13298] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 06/20/2018] [Accepted: 06/21/2018] [Indexed: 12/27/2022] Open
Abstract
Nattokinase (NK) is an important serine‐protease with direct fibrinolytic activity involving the prevention of cardiovascular disease as an antithrombotic agent. Dozens of studies have focused on the characterization of intrinsic novel promoters and signal peptides to the secretory production of recombinant proteins in Bacillus subtilis. However, intrinsic genetic elements have several drawbacks, which cannot mediate the production of NK to the desired level. In this study, the genetic elements, which were used to overproduce the recombinant secretory NK, were rationally modified in B. subtilis in a stepwise manner. The first step was to select a suitable signal peptide for the highly efficient secretion of NK. By comparison of the secretory levels mediated by two different signal peptides, which were encoded by the genes of a minor extracellular protease epr (SPepr) and cell‐wall associated protease wapA (SPwapA), respectively, SPwapA was verified as the superior secretory element. Second, P04, which was a synthetic promoter screened from an array of mutants based on the promoter cloned from the operon of a quorum‐sensing associated gene srfA (PsrfA), was paired to SPwapA. The secretory level of NK was obviously augmented by the combination of these two genetic elements. Third, the cis‐acting element CodY‐binding sequence positioned at the 5′UTR was deleted (yielding P08), and thus the secretory level was significantly elevated. The activity of NK, which was defined as fibrinolytic units (FU), reached to a level of 270 FU ml−1. Finally, the superior genetic element composed of P08 and SPwapA was utilized to overproduce NK in the host B. subtilis WB800, which was able to produce the secretory NK at 292 FU ml−1. The strategy established in this study can not only be used to overproduce NK in B. subtilis but also might be a promising pipeline to modify the genetic element for the synthetic secretory system.
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Affiliation(s)
- Wenjing Cui
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Feiya Suo
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Jintao Cheng
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Laichuang Han
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Wenliang Hao
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Junling Guo
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Zhemin Zhou
- School of Biotechnology, Key Laboratory of Industrial Biotechnology (Ministry of Education), Jiangnan University, Wuxi, Jiangsu, 214122, China
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Drejer EB, Hakvåg S, Irla M, Brautaset T. Genetic Tools and Techniques for Recombinant Expression in Thermophilic Bacillaceae. Microorganisms 2018; 6:microorganisms6020042. [PMID: 29748477 PMCID: PMC6027425 DOI: 10.3390/microorganisms6020042] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 05/02/2018] [Accepted: 05/03/2018] [Indexed: 01/17/2023] Open
Abstract
Although Escherichia coli and Bacillus subtilis are the most prominent bacterial hosts for recombinant protein production by far, additional species are being explored as alternatives for production of difficult-to-express proteins. In particular, for thermostable proteins, there is a need for hosts able to properly synthesize, fold, and excrete these in high yields, and thermophilic Bacillaceae represent one potentially interesting group of microorganisms for such purposes. A number of thermophilic Bacillaceae including B.methanolicus, B.coagulans, B.smithii, B.licheniformis, Geobacillus thermoglucosidasius, G. kaustophilus, and G. stearothermophilus are investigated concerning physiology, genomics, genetic tools, and technologies, altogether paving the way for their utilization as hosts for recombinant production of thermostable and other difficult-to-express proteins. Moreover, recent successful deployments of CRISPR/Cas9 in several of these species have accelerated the progress in their metabolic engineering, which should increase their attractiveness for future industrial-scale production of proteins. This review describes the biology of thermophilic Bacillaceae and in particular focuses on genetic tools and methods enabling use of these organisms as hosts for recombinant protein production.
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Affiliation(s)
- Eivind B Drejer
- Department of Biotechnology and Food Science, NTNU: Norwegian University of Science and Technology, 7491 Trondheim, Norway.
| | - Sigrid Hakvåg
- Department of Biotechnology and Food Science, NTNU: Norwegian University of Science and Technology, 7491 Trondheim, Norway.
| | - Marta Irla
- Department of Biotechnology and Food Science, NTNU: Norwegian University of Science and Technology, 7491 Trondheim, Norway.
| | - Trygve Brautaset
- Department of Biotechnology and Food Science, NTNU: Norwegian University of Science and Technology, 7491 Trondheim, Norway.
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Development of an Efficient Genome Editing Tool in Bacillus licheniformis Using CRISPR-Cas9 Nickase. Appl Environ Microbiol 2018; 84:AEM.02608-17. [PMID: 29330178 DOI: 10.1128/aem.02608-17] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 12/23/2017] [Indexed: 01/20/2023] Open
Abstract
Bacillus strains are important industrial bacteria that can produce various biochemical products. However, low transformation efficiencies and a lack of effective genome editing tools have hindered its widespread application. Recently, clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 techniques have been utilized in many organisms as genome editing tools because of their high efficiency and easy manipulation. In this study, an efficient genome editing method was developed for Bacillus licheniformis using a CRISPR-Cas9 nickase integrated into the genome of B. licheniformis DW2 with overexpression driven by the P43 promoter. The yvmC gene was deleted using the CRISPR-Cas9n technique with homology arms of 1.0 kb as a representative example, and an efficiency of 100% was achieved. In addition, two genes were simultaneously disrupted with an efficiency of 11.6%, and the large DNA fragment bacABC (42.7 kb) was deleted with an efficiency of 79.0%. Furthermore, the heterologous reporter gene aprN, which codes for nattokinase in Bacillus subtilis, was inserted into the chromosome of B. licheniformis with an efficiency of 76.5%. The activity of nattokinase in the DWc9nΔ7/pP43SNT-SsacC strain reached 59.7 fibrinolytic units (FU)/ml, which was 25.7% higher than that of DWc9n/pP43SNT-SsacC Finally, the engineered strain DWc9nΔ7 (Δepr ΔwprA Δmpr ΔaprE Δvpr ΔbprA ΔbacABC), with multiple disrupted genes, was constructed using the CRISPR-Cas9n technique. Taken together, we have developed an efficient genome editing tool based on CRISPR-Cas9n in B. licheniformis This tool could be applied to strain improvement for future research.IMPORTANCE As important industrial bacteria, Bacillus strains have attracted significant attention due to their production of biological products. However, genetic manipulation of these bacteria is difficult. The CRISPR-Cas9 system has been applied to genome editing in some bacteria, and CRISPR-Cas9n was proven to be an efficient and precise tool in previous reports. The significance of our research is the development of an efficient, more precise, and systematic genome editing method for single-gene deletion, multiple-gene disruption, large DNA fragment deletion, and single-gene integration in Bacillus licheniformis via Cas9 nickase. We also applied this method to the genetic engineering of the host strain for protein expression.
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Cai D, Hu S, Chen Y, Liu L, Yang S, Ma X, Chen S. Enhanced Production of Poly-γ-glutamic acid by Overexpression of the Global Anaerobic Regulator Fnr in Bacillus licheniformis WX-02. Appl Biochem Biotechnol 2018; 185:958-970. [PMID: 29388009 DOI: 10.1007/s12010-018-2693-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 01/03/2018] [Indexed: 10/18/2022]
Abstract
Poly-γ-glutamic acid is a multi-functional biopolymer with various applications. ATP supply plays an important role in poly-γ-glutamic acid (γ-PGA) synthesis. Global anaerobic regulator Fnr plays a key role in anaerobic adaptation and nitrate respiration, which might affect ATP generation during γ-PGA synthesis. In this study, we have improved γ-PGA production by overexpression of Fnr in Bacillus licheniformis WX-02. First, the gene fnr was knocked out in WX-02, and the γ-PGA yields have no significant differences between WX-02 and the fnr-deficient strain WXΔfnr in the medium without nitrate (BFC medium). However, the γ-PGA yield of 8.95 g/L, which was produced by WXΔfnr in the medium with nitrate addition (BFCN medium), decreased by 74% compared to WX-02 (34.53 g/L). Then, the fnr complementation strain WXΔfnr/pHY-fnr restored the γ-PGA synthesis capability, and γ-PGA yield was increased by 13% in the Fnr overexpression strain WX/pHY-fnr (39.96 g/L) in BFCN medium, compared to WX/pHY300 (35.41 g/L). Furthermore, the transcriptional levels of narK, narG, and hmp were increased by 5.41-, 4.93-, and 3.93-fold in WX/pHY-fnr, respectively, which led to the increases of nitrate consumption rate and ATP supply for γ-PGA synthesis. Collectively, Fnr affects γ-PGA synthesis mainly through manipulating the expression level of nitrate metabolism, and this study provides a novel strategy to improve γ-PGA production by overexpression of Fnr.
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Affiliation(s)
- Dongbo Cai
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Shiying Hu
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Yaozhong Chen
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Li Liu
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Shihui Yang
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China
| | - Xin Ma
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China.
| | - Shouwen Chen
- Environmental Microbial Technology Center of Hubei Province, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062, China.
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High-level production of α-amylase by manipulating the expression of alanine racamase in Bacillus licheniformis. Biotechnol Lett 2017; 39:1389-1394. [DOI: 10.1007/s10529-017-2359-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 05/09/2017] [Indexed: 01/04/2023]
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Cai D, Wang H, He P, Zhu C, Wang Q, Wei X, Nomura CT, Chen S. A novel strategy to improve protein secretion via overexpression of the SppA signal peptide peptidase in Bacillus licheniformis. Microb Cell Fact 2017; 16:70. [PMID: 28438200 PMCID: PMC5404308 DOI: 10.1186/s12934-017-0688-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Accepted: 04/21/2017] [Indexed: 12/21/2022] Open
Abstract
Background Signal peptide peptidases play an important role in the removal of remnant signal peptides in the cell membrane, a critical step for extracellular protein production. Although these proteins are likely a central component for extracellular protein production, there has been a lack of research on whether protein secretion could be enhanced via overexpression of signal peptide peptidases. Results In this study, both nattokinase and α-amylase were employed as prototypical secreted target proteins to evaluate the function of putative signal peptide peptidases (SppA and TepA) in Bacillus licheniformis. We observed dramatic decreases in the concentrations of both target proteins (45 and 49%, respectively) in a sppA deficient strain, while the extracellular protein yields of nattokinase and α-amylase were increased by 30 and 67% respectively in a strain overexpressing SppA. In addition, biomass, specific enzyme activities and the relative gene transcriptional levels were also enhanced due to the overexpression of sppA, while altering the expression levels of tepA had no effect on the concentrations of the secreted target proteins. Conclusions Our results confirm that SppA, but not TepA, plays an important functional role for protein secretion in B. licheniformis. Our results indicate that the sppA overexpression strain, B. licheniformis BL10GS, could be used as a promising host strain for the industrial production of heterologous secreted proteins. Electronic supplementary material The online version of this article (doi:10.1186/s12934-017-0688-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Dongbo Cai
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, No. 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Hao Wang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, No. 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Penghui He
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, No. 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Chengjun Zhu
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, No. 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Qin Wang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, No. 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China
| | - Xuetuan Wei
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Christopher T Nomura
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, No. 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China.,Department of Chemistry, The State University of New York College of Environmental Science and Forestry (SUNY ESF), Syracuse, NY, 13210, USA
| | - Shouwen Chen
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, No. 368 Youyi Avenue, Wuchang District, Wuhan, 430062, Hubei, People's Republic of China.
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Microbial production of nattokinase: current progress, challenge and prospect. World J Microbiol Biotechnol 2017; 33:84. [DOI: 10.1007/s11274-017-2253-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 03/28/2017] [Indexed: 12/19/2022]
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50
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A novel approach to improve poly-γ-glutamic acid production by NADPH Regeneration in Bacillus licheniformis WX-02. Sci Rep 2017; 7:43404. [PMID: 28230096 PMCID: PMC5322528 DOI: 10.1038/srep43404] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 01/24/2017] [Indexed: 01/15/2023] Open
Abstract
Poly-γ-glutamic acid (γ-PGA) is an important biochemical product with a variety of applications. This work reports a novel approach to improve γ-PGA through over expression of key enzymes in cofactor NADPH generating process for NADPH pool. Six genes encoding the key enzymes in NADPH generation were over-expressed in the γ-PGA producing strain B. licheniformis WX-02. Among various recombinants, the strain over-expressing zwf gene (coding for glucose-6-phosphate dehydrogenase), WX-zwf, produced the highest γ-PGA concentration (9.13 g/L), 35% improvement compared to the control strain WX-pHY300. However, the growth rates and glucose uptake rates of the mutant WX-zwf were decreased. The transcriptional levels of the genes pgsB and pgsC responsible for γ-PGA biosynthesis were increased by 8.21- and 5.26-fold, respectively. The Zwf activity of the zwf over expression strain increased by 9.28-fold, which led to the improvement of the NADPH generation, and decrease of accumulation of by-products acetoin and 2,3-butanediol. Collectively, these results demonstrated that NADPH generation via over-expression of Zwf is as an effective strategy to improve the γ-PGA production in B. licheniformis.
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