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Wang D, Fu X, Gao J, Zhao X, Bai W. Enhancing Poly-γ-glutamic Acid Production in Bacillus tequilensis BL01 through a Multienzyme Assembly Strategy and Expression Features of Glutamate Synthesis from Corynebacterium glutamicum. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:8674-8683. [PMID: 38569079 DOI: 10.1021/acs.jafc.4c00685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/05/2024]
Abstract
The enhancement of intracellular glutamate synthesis in glutamate-independent poly-γ-glutamic acid (γ-PGA)-producing strains is an essential strategy for improving γ-PGA production. Bacillus tequilensis BL01ΔpgdSΔggtΔsucAΔgudB:P43-ppc-pyk-gdhA for the efficient synthesis of γ-PGA was constructed through expression of glutamate synthesis features of Corynebacterium glutamicum, which increased the titer of γ-PGA by 2.18-fold (3.24 ± 0.22 g/L) compared to that of B. tequilensis BL01ΔpgdSΔggtΔsucAΔgudB (1.02 ± 0.11 g/L). To further improve the titer of γ-PGA and decrease the production of byproducts, three enzymes (Ppc, Pyk, and AceE) were assembled to a complex using SpyTag/Catcher pairs. The results showed that the γ-PGA titer of the assembled strain was 31.31% higher than that of the unassembled strain. To further reduce the production cost, 25.73 ± 0.69 g/L γ-PGA with a productivity of 0.48 g/L/h was obtained from cheap molasses. This work provides new metabolic engineering strategies to improve the production of γ-PGA in B. tequilensis BL01. Furthermore, the engineered strain has great potential for the industrial production of γ-PGA from molasses.
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Affiliation(s)
- Dexin Wang
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Xiaoping Fu
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Jiaqi Gao
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
- University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Xingya Zhao
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
| | - Wenqin Bai
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
- National Center of Technology Innovation for Synthetic Biology, 32 West Seventh Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
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Qiu Y, Xu D, Lei P, Li S, Xu H. Engineering functional homopolymeric amino acids: from biosynthesis to design. Trends Biotechnol 2024; 42:310-325. [PMID: 37775417 DOI: 10.1016/j.tibtech.2023.08.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/08/2023] [Accepted: 08/31/2023] [Indexed: 10/01/2023]
Abstract
Homopolymeric amino acids (HPAs) are a class of microbial polymers that can be classified into two categories: anionic and cationic HPAs. Notable examples include γ-poly-glutamic acid (γ-PGA) and ε-poly-L-lysine (ε-PL) that have wide-ranging applications in medicine, food, and agriculture. The primary method of manufacture is through microbial synthesis. In recent decades significant efforts have been made to enhance the production of HPAs, specifically focusing on γ-PGA and ε-PL. We comprehensively review current advances in understanding the synthetic mechanisms as well as metabolic engineering and fermentation process techniques to improve the production of HPAs. In addition, we discuss the major challenges and solutions associated with desired structure regulation of HPAs and the development of novel structures.
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Affiliation(s)
- Yibin Qiu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, PR China
| | - Delei Xu
- College of Biological and Food Engineering, Changshu Institute of Technology, 99 South Third Ring Road, Changshu 215500, PR China
| | - Peng Lei
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, PR China
| | - Sha Li
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, PR China.
| | - Hong Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, PR China; Nanjing Shineking Biotech Co. Ltd., Nanjing 210061, PR China.
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3
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Elbanna K, Alsulami FS, Neyaz LA, Abulreesh HH. Poly (γ) glutamic acid: a unique microbial biopolymer with diverse commercial applicability. Front Microbiol 2024; 15:1348411. [PMID: 38414762 PMCID: PMC10897055 DOI: 10.3389/fmicb.2024.1348411] [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: 12/02/2023] [Accepted: 01/19/2024] [Indexed: 02/29/2024] Open
Abstract
Microbial biopolymers have emerged as promising solutions for environmental pollution-related human health issues. Poly-γ-glutamic acid (γ-PGA), a natural anionic polymeric compound, is composed of highly viscous homo-polyamide of D and L-glutamic acid units. The extracellular water solubility of PGA biopolymer facilitates its complete biodegradation and makes it safe for humans. The unique properties have enabled its applications in healthcare, pharmaceuticals, water treatment, foods, and other domains. It is applied as a thickener, taste-masking agent, stabilizer, texture modifier, moisturizer, bitterness-reducing agent, probiotics cryoprotectant, and protein crystallization agent in food industries. γ-PGA is employed as a biological adhesive, drug carrier, and non-viral vector for safe gene delivery in tissue engineering, pharmaceuticals, and medicine. It is also used as a moisturizer to improve the quality of hair care and skincare cosmetic products. In agriculture, it serves as an ideal stabilizer, environment-friendly fertilizer synergist, plant-growth promoter, metal biosorbent in soil washing, and animal feed additive to reduce body fat and enhance egg-shell strength.
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Affiliation(s)
- Khaled Elbanna
- Department of Biology, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
- Research Laboratories Unit, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
- Department of Agricultural Microbiology, Faculty of Agriculture, Fayoum University, Fayoum, Egypt
| | - Fatimah S Alsulami
- Department of Biology, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
- Research Laboratories Unit, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Leena A Neyaz
- Department of Biology, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
- Research Laboratories Unit, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Hussein H Abulreesh
- Department of Biology, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
- Research Laboratories Unit, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
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4
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Dueñas C, Pagano A, Calvio C, Srikanthan DS, Slamet-Loedin I, Balestrazzi A, Macovei A. Genotype-specific germination behavior induced by sustainable priming techniques in response to water deprivation stress in rice. FRONTIERS IN PLANT SCIENCE 2024; 15:1344383. [PMID: 38390302 PMCID: PMC10881859 DOI: 10.3389/fpls.2024.1344383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Accepted: 01/22/2024] [Indexed: 02/24/2024]
Abstract
Water stress brought about by climate change is among the major global concerns threatening food security. Rice is an important staple food which requires high water resources. Being a semi-aquatic plant, rice is particularly susceptible to drought. The aim of this work was to develop techniques directed to promote rice resilience to water deprivation stress during germination by implementing specific seed priming treatments. Five popular Italian rice varieties were subjected to priming treatments using novel, sustainable solutions, like poly-gamma-glutamic acid (γ-PGA), denatured γ-PGA (dPGA), and iron (Fe) pulsing, alone or in combination. The effect of the developed priming methods was tested under optimal conditions as well as under water deprivation stress imposed by polyethylene glycol (PEG) treatments. The priming efficacy was phenotypically determined in terms of germination behavior by measuring a series of parameters (germinability, germination index, mean germination time, seed vigor index, root and shoot length, germination stress tolerance index). Biochemical analyses were carried out to measure the levels of iron uptake and accumulation of reactive oxygen species (ROS). Integrative data analyses revealed that the rice varieties exhibited a strong genotype- and treatment-specific germination behavior. PEG strongly inhibited germination while most of the priming treatments were able to rescue it in all varieties tested except for Unico, which can be defined as highly stress sensitive. Molecular events (DNA repair, antioxidant response, iron homeostasis) associated with the transition from seed to seedling were monitored in terms of changes in gene expression profiles in two varieties sensitive to water deprivation stress with different responses to priming. The investigated genes appeared to be differentially expressed in a genotype-, priming treatment-, stress- and stage-dependent manner. The proposed seed priming treatments can be envisioned as sustainable and versatile agricultural practices that could help in addressing the impact of climate challenges on the agri-food system.
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Affiliation(s)
- Conrado Dueñas
- Department of Biology and Biotechnology 'L. Spallanzani', University of Pavia, Pavia, Italy
| | - Andrea Pagano
- Department of Biology and Biotechnology 'L. Spallanzani', University of Pavia, Pavia, Italy
| | - Cinzia Calvio
- Department of Biology and Biotechnology 'L. Spallanzani', University of Pavia, Pavia, Italy
| | | | - Inez Slamet-Loedin
- Trait and Genome Engineering Cluster, Rice Breeding Innovations, International Rice Research Institute, Metro Manila, Philippines
| | - Alma Balestrazzi
- Department of Biology and Biotechnology 'L. Spallanzani', University of Pavia, Pavia, Italy
| | - Anca Macovei
- Department of Biology and Biotechnology 'L. Spallanzani', University of Pavia, Pavia, Italy
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Qian J, Wang Y, Hu Z, Shi T, Wang Y, Ye C, Huang H. Bacillus sp. as a microbial cell factory: Advancements and future prospects. Biotechnol Adv 2023; 69:108278. [PMID: 37898328 DOI: 10.1016/j.biotechadv.2023.108278] [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: 07/07/2023] [Revised: 09/27/2023] [Accepted: 10/25/2023] [Indexed: 10/30/2023]
Abstract
Bacillus sp. is one of the most distinctive gram-positive bacteria, able to grow efficiently using cheap carbon sources and secrete a variety of useful substances, which are widely used in food, pharmaceutical, agricultural and environmental industries. At the same time, Bacillus sp. is also recognized as a safe genus with a relatively clear genetic background, which is conducive to the industrial production of target metabolites. In this review, we discuss the reasons why Bacillus sp. has been so extensively studied and summarize its advances in systems and synthetic biology, engineering strategies to improve microbial cell properties, and industrial applications in several metabolic engineering applications. Finally, we present the current challenges and possible solutions to provide a reliable basis for Bacillus sp. as a microbial cell factory.
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Affiliation(s)
- Jinyi Qian
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Yuzhou Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Zijian Hu
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China
| | - Tianqiong Shi
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China.
| | - Yuetong Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China.
| | - Chao Ye
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China.
| | - He Huang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, PR China.
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Effects of Fe 2+ addition to sugarcane molasses on poly-γ-glutamic acid production in Bacillus licheniformis CGMCC NO. 23967. Microb Cell Fact 2023; 22:37. [PMID: 36829191 PMCID: PMC9960700 DOI: 10.1186/s12934-023-02042-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 02/12/2023] [Indexed: 02/26/2023] Open
Abstract
BACKGROUND Poly-γ-glutamic acid (γ-PGA) is biodegradable, water-soluble, environment-friendly, and edible. Consequently, it has a variety of industrial applications. It is crucial to control production cost and increase output for industrial production γ-PGA. RESULTS Here γ-PGA production from sugarcane molasses by Bacillus licheniformis CGMCC NO. 23967 was studied in shake-flasks and bioreactors, the results indicate that the yield of γ-PGA could reach 40.668 g/L in a 5L stirred tank fermenter. Further study found that γ-PGA production reached 70.436 g/L, γ-PGA production and cell growth increased by 73.20% and 55.44%, respectively, after FeSO4·7H2O was added. Therefore, we investigated the metabolomic and transcriptomic changes following FeSO4·7H2O addition. This addition resulted in increased abundance of intracellular metabolites, including amino acids, organic acids, and key TCA cycle intermediates, as well as upregulation of the glycolysis pathway and TCA cycle. CONCLUSIONS These results compare favorably with those obtained from glucose and other forms of biomass feedstock, confirming that sugarcane molasses can be used as an economical substrate without any pretreatment. The addition of FeSO4·7H2O to sugarcane molasses may increase the efficiency of γ-PGA production in intracellular.
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Nair P, Navale GR, Dharne MS. Poly-gamma-glutamic acid biopolymer: a sleeping giant with diverse applications and unique opportunities for commercialization. BIOMASS CONVERSION AND BIOREFINERY 2023; 13:4555-4573. [PMID: 33824848 PMCID: PMC8016157 DOI: 10.1007/s13399-021-01467-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/19/2021] [Accepted: 03/23/2021] [Indexed: 05/06/2023]
Abstract
Poly-gamma-glutamic acid (γ-PGA) is a biodegradable, non-toxic, ecofriendly, and non-immunogenic biopolymer. Its phenomenal properties have gained immense attention in the field of regenerative medicine, the food industry, wastewater treatment, and even in 3D printing bio-ink. The γ-PGA has the potential to replace synthetic non-degradable counterparts, but the main obstacle is the high production cost and lower productivity. Extensive research has been carried out to reduce the production cost by using different waste; however, it is unable to match the commercialization needs. This review focuses on the biosynthetic mechanism of γ-PGA, its production using the synthetic medium as well as different wastes by L-glutamic acid-dependent and independent microbial strains. Furthermore, various metabolic engineering strategies and the recovery processes for γ-PGA and their possible applications are discussed. Finally, highlights on the challenges and unique approaches to reduce the production cost and to increase the productivity for commercialization of γ-PGA are also summarized.
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Affiliation(s)
- Pranav Nair
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
- National Collection of Industrial Microorganisms (NCIM), CSIR-National Chemical Laboratory, Pune, 411008 India
| | - Govinda R. Navale
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
- National Collection of Industrial Microorganisms (NCIM), CSIR-National Chemical Laboratory, Pune, 411008 India
| | - Mahesh S. Dharne
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
- National Collection of Industrial Microorganisms (NCIM), CSIR-National Chemical Laboratory, Pune, 411008 India
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8
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Parati M, Khalil I, Tchuenbou-Magaia F, Adamus G, Mendrek B, Hill R, Radecka I. Building a circular economy around poly(D/L-γ-glutamic acid)- a smart microbial biopolymer. Biotechnol Adv 2022; 61:108049. [DOI: 10.1016/j.biotechadv.2022.108049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 10/03/2022] [Accepted: 10/06/2022] [Indexed: 11/26/2022]
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Li J, Chen S, Fu J, Xie J, Ju J, Yu B, Wang L. Efficient molasses utilization for low-molecular-weight poly-γ-glutamic acid production using a novel Bacillus subtilis stain. Microb Cell Fact 2022; 21:140. [PMID: 35842664 PMCID: PMC9287850 DOI: 10.1186/s12934-022-01867-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Accepted: 07/05/2022] [Indexed: 11/26/2022] Open
Abstract
Background Poly-γ-glutamic acid (γ-PGA) is a biopolymer and has various applications based on its biocompatibility, non-toxicity, and edibility. Low-molecular-weight (Mw)-γ-PGA has promising applications in agriculture and pharmaceuticals. It is traditionally produced by enzymatic hydrolysis. Cost-effective bioproduction of low-Mw-γ-PGA is essential for commercial application of γ-PGA. Results Bacillus subtilis 242 is a newly isolated low-Mw-γ-PGA-producing strain. To develop cost-effective production of γ-PGA using this newly isolated strain, cane molasses and corn steep liquor were used to produce γ-PGA. The concentration of cane molasses was optimized and 100 g/L cane molasses resulted in high γ-PGA production. The effects of yeast extract and corn steep liquor on γ-PGA yield were investigated. High concentration of γ-PGA was obtained in the medium with corn steep liquor. A concentration of 32.14 g/L γ-PGA was achieved in fed-batch fermentation, with a productivity of 0.67 g/L/h and a percentage yield (gγ-PGA/gglutamate) of 106.39%. The Mw of γ-PGA was 27.99 kDa. Conclusion This study demonstrated the potential application of B. subtilis 242 for cost-effective production of low-Mw-γ-PGA from cane molasses.
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Affiliation(s)
- Jing Li
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology & Business University (BTBU), Beijing, 100048, People's Republic of China.,College of Life Science, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China.,CAS Key Laboratory of Microbial Physiological & Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Shengbao Chen
- CAS Key Laboratory of Microbial Physiological & Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Jiaming Fu
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Jianchun Xie
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology & Business University (BTBU), Beijing, 100048, People's Republic of China
| | - Jiansong Ju
- College of Life Science, Hebei Normal University, Shijiazhuang, 050024, People's Republic of China
| | - Bo Yu
- CAS Key Laboratory of Microbial Physiological & Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Limin Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology & Business University (BTBU), Beijing, 100048, People's Republic of China. .,CAS Key Laboratory of Microbial Physiological & Metabolic Engineering, State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
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Kumar V, Bansal V, Madhavan A, Kumar M, Sindhu R, Awasthi MK, Binod P, Saran S. Active pharmaceutical ingredient (API) chemicals: a critical review of current biotechnological approaches. Bioengineered 2022; 13:4309-4327. [PMID: 35135435 PMCID: PMC8973766 DOI: 10.1080/21655979.2022.2031412] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The aim of this article was to generate a framework of bio-based economy by an effective utilization of biomass from the perspectives of agriculture for developing potential end bio-based products (e.g. pharmaceuticals, active pharmaceutical ingredients). Our discussion is also extended to the conservatory ways of bioenergy along with development of bio-based products and biofuels. This review article further showcased the fundamental principles for producing these by-products. Thereby, the necessity of creating these products is to be efficaciously utilization by small-scale farmers that can aid the local needs for bio-based materials and energy. Concurrently, the building up of small markets will open up the avenues and linkages for bigger markets. In nutshell, the aim of the review is to explore the pathway of the biotechnological approaches so that less chosen producers and underdeveloped areas can be allied so that pressure on the systems of biomass production can be relaxed.
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Affiliation(s)
- Vinod Kumar
- Fermentation Technology and Microbial Biotechnology Division, Csir- Indian Institute of Integrative Medicine (Csir-iiim), J & K, India.,Academy of Scientific and Innovative Research (Acsir), Ghaziabad-India
| | - Vasudha Bansal
- Department of Foods and Nutrition, Government Home Science College, Affiliated to Panjab University, Chandigarh, India
| | - Aravind Madhavan
- Division of Infectious Disease Biology, Rajiv Gandhi Centre for Biotechnology, - Trivandrum- India
| | - Manoj Kumar
- Fermentation Technology and Microbial Biotechnology Division, Csir- Indian Institute of Integrative Medicine (Csir-iiim), J & K, India.,Academy of Scientific and Innovative Research (Acsir), Ghaziabad-India
| | - Raveendran Sindhu
- Deapartment of Food Technology, Tkm Institute of Technology, Kollam-India
| | - Mukesh Kumar Awasthi
- Department of Resource and Environmental Science, College of Natural Resources and Environment, Northwest A&f University, Shaanxi Province, Yangling, PR China
| | - Parameswaran Binod
- Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary, Science and Technology (Csir-niist), Trivandrum- India
| | - Saurabh Saran
- Fermentation Technology and Microbial Biotechnology Division, Csir- Indian Institute of Integrative Medicine (Csir-iiim), J & K, India
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Johnson LC, Akinmola AT, Scholz C. Poly(glutamic acid): From natto to drug delivery systems. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2022. [DOI: 10.1016/j.bcab.2022.102292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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12
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Ji G, Xu L, Lyu Q, Liu Y, Gong X, Li X, Yan Z. Poly-γ-glutamic acid production by simultaneous saccharification and fermentation using corn straw and its fertilizer synergistic effect evaluation. Bioprocess Biosyst Eng 2021; 44:2181-2191. [PMID: 34086133 DOI: 10.1007/s00449-021-02593-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 05/25/2021] [Indexed: 10/21/2022]
Abstract
Agricultural wastes rich in lignocellulosic biomass have been used in the production of poly-γ-glutamic acid (γ-PGA) through separate hydrolysis and fermentation (SHF), but this process is complicated and generates a lot of wastes. In order to find a simpler and greener way to produce γ-PGA using agricultural wastes, this study attempted to establish simultaneous saccharification and fermentation (SSF) with citric acid-pretreated corn straw. The possibility of Bacillus amyloliquefaciens JX-6 using corn straw as substrate to synthesize γ-PGA was validated, and the results showed that increasing the proportion of glucose in the substrate could improve the γ-PGA yield. Based on these preliminary results, the corn straw was pretreated using citric acid. Then, the liquid fraction (xylan-rich) was used for cultivation of seed culture, and the solid fraction (glucan-rich) was used as the substrate for SSF. In a 10-L fermenter, the maximum cumulative γ-PGA concentration in batch and fed-batch SSF were 5.08 ± 0.78 g/L and 10.78 ± 0.32 g/L, respectively. Moreover, the product from SSF without γ-PGA extraction was used as a fertilizer synergist, increasing the yield of pepper by 13.46% (P < 0.05). Our study greatly simplified the production steps of γ-PGA, and each step achieved zero emission as far as possible. The SSF process for γ-PGA production provided a simple and green way for lignocellulose biorefinery and sustainable cultivation in agriculture.
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Affiliation(s)
- Gaosheng Ji
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, People's Republic of China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lishan Xu
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, People's Republic of China
| | - Qingyang Lyu
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, People's Republic of China
| | - Yang Liu
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, People's Republic of China
| | - Xuefeng Gong
- Institute of Horticulture, Sichuan Academy of Agricultural Sciences, Chengdu, 610066, China
| | - Xudong Li
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, People's Republic of China
| | - Zhiying Yan
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, People's Republic of China.
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Blanco FG, Hernández N, Rivero-Buceta V, Maestro B, Sanz JM, Mato A, Hernández-Arriaga AM, Prieto MA. From Residues to Added-Value Bacterial Biopolymers as Nanomaterials for Biomedical Applications. NANOMATERIALS 2021; 11:nano11061492. [PMID: 34200068 PMCID: PMC8228158 DOI: 10.3390/nano11061492] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/20/2021] [Accepted: 05/26/2021] [Indexed: 12/16/2022]
Abstract
Bacterial biopolymers are naturally occurring materials comprising a wide range of molecules with diverse chemical structures that can be produced from renewable sources following the principles of the circular economy. Over the last decades, they have gained substantial interest in the biomedical field as drug nanocarriers, implantable material coatings, and tissue-regeneration scaffolds or membranes due to their inherent biocompatibility, biodegradability into nonhazardous disintegration products, and their mechanical properties, which are similar to those of human tissues. The present review focuses upon three technologically advanced bacterial biopolymers, namely, bacterial cellulose (BC), polyhydroxyalkanoates (PHA), and γ-polyglutamic acid (PGA), as models of different carbon-backbone structures (polysaccharides, polyesters, and polyamides) produced by bacteria that are suitable for biomedical applications in nanoscale systems. This selection models evidence of the wide versatility of microorganisms to generate biopolymers by diverse metabolic strategies. We highlight the suitability for applied sustainable bioprocesses for the production of BC, PHA, and PGA based on renewable carbon sources and the singularity of each process driven by bacterial machinery. The inherent properties of each polymer can be fine-tuned by means of chemical and biotechnological approaches, such as metabolic engineering and peptide functionalization, to further expand their structural diversity and their applicability as nanomaterials in biomedicine.
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Affiliation(s)
- Francisco G. Blanco
- Interdisciplinary Platform for Sustainable Plastics towards a Circular Economy-Spanish National Research Council (SusPlast-CSIC), 28040 Madrid, Spain; (F.G.B.); (N.H.); (V.R.-B.); (A.M.); (A.M.H.-A.)
- Polymer Biotechnology Group, Microbial and Plant Biotechnology Department, Biological Research Centre Margarita Salas, CIB-CSIC, 28040 Madrid, Spain
| | - Natalia Hernández
- Interdisciplinary Platform for Sustainable Plastics towards a Circular Economy-Spanish National Research Council (SusPlast-CSIC), 28040 Madrid, Spain; (F.G.B.); (N.H.); (V.R.-B.); (A.M.); (A.M.H.-A.)
- Polymer Biotechnology Group, Microbial and Plant Biotechnology Department, Biological Research Centre Margarita Salas, CIB-CSIC, 28040 Madrid, Spain
| | - Virginia Rivero-Buceta
- Interdisciplinary Platform for Sustainable Plastics towards a Circular Economy-Spanish National Research Council (SusPlast-CSIC), 28040 Madrid, Spain; (F.G.B.); (N.H.); (V.R.-B.); (A.M.); (A.M.H.-A.)
- Polymer Biotechnology Group, Microbial and Plant Biotechnology Department, Biological Research Centre Margarita Salas, CIB-CSIC, 28040 Madrid, Spain
| | - Beatriz Maestro
- Host-Parasite Interplay in Pneumococcal Infection Group, Microbial and Plant Biotechnology Department, Biological Research Centre Margarita Salas, CIB-CSIC, 28040 Madrid, Spain; (B.M.); (J.M.S.)
| | - Jesús M. Sanz
- Host-Parasite Interplay in Pneumococcal Infection Group, Microbial and Plant Biotechnology Department, Biological Research Centre Margarita Salas, CIB-CSIC, 28040 Madrid, Spain; (B.M.); (J.M.S.)
| | - Aránzazu Mato
- Interdisciplinary Platform for Sustainable Plastics towards a Circular Economy-Spanish National Research Council (SusPlast-CSIC), 28040 Madrid, Spain; (F.G.B.); (N.H.); (V.R.-B.); (A.M.); (A.M.H.-A.)
- Polymer Biotechnology Group, Microbial and Plant Biotechnology Department, Biological Research Centre Margarita Salas, CIB-CSIC, 28040 Madrid, Spain
| | - Ana M. Hernández-Arriaga
- Interdisciplinary Platform for Sustainable Plastics towards a Circular Economy-Spanish National Research Council (SusPlast-CSIC), 28040 Madrid, Spain; (F.G.B.); (N.H.); (V.R.-B.); (A.M.); (A.M.H.-A.)
- Polymer Biotechnology Group, Microbial and Plant Biotechnology Department, Biological Research Centre Margarita Salas, CIB-CSIC, 28040 Madrid, Spain
| | - M. Auxiliadora Prieto
- Interdisciplinary Platform for Sustainable Plastics towards a Circular Economy-Spanish National Research Council (SusPlast-CSIC), 28040 Madrid, Spain; (F.G.B.); (N.H.); (V.R.-B.); (A.M.); (A.M.H.-A.)
- Polymer Biotechnology Group, Microbial and Plant Biotechnology Department, Biological Research Centre Margarita Salas, CIB-CSIC, 28040 Madrid, Spain
- Correspondence:
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14
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Park SA, Bhatia SK, Park HA, Kim SY, Sudheer PDVN, Yang YH, Choi KY. Bacillus subtilis as a robust host for biochemical production utilizing biomass. Crit Rev Biotechnol 2021; 41:827-848. [PMID: 33622141 DOI: 10.1080/07388551.2021.1888069] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Bacillus subtilis is regarded as a suitable host for biochemical production owing to its excellent growth and bioresource utilization characteristics. In addition, the distinct endogenous metabolic pathways and the suitability of the heterologous pathways have made B. subtilis a robust and promising host for producing biochemicals, such as: bioalcohols; bioorganic acids (lactic acids, α-ketoglutaric acid, and γ-aminobutyric acid); biopolymers (poly(γ-glutamic acid, polyhydroxyalkanoates (PHA), and polysaccharides and monosaccharides (N-acetylglucosamine, xylooligosaccharides, and hyaluronic acid)); and bioflocculants. Also for producing oligopeptides and functional peptides, owing to its efficient protein secretion system. Several metabolic and genetic engineering techniques, such as target gene overexpression and inactivation of bypass pathways, have led to the improvement in production titers and product selectivity. In this review article, recent progress in the utilization of robust B. subtilis-based host systems for biomass conversion and biochemical production has been highlighted, and the prospects of such host systems are suggested.
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Affiliation(s)
- Seo A Park
- Department of Environmental Engineering, College of Engineering, Ajou University, Suwon, South Korea
| | - Shashi Kant Bhatia
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, Republic of Korea.,Institute for Ubiquitous Information Technology and Application, Konkuk University, Seoul, Republic of Korea
| | - Hyun A Park
- Department of Environmental Engineering, College of Engineering, Ajou University, Suwon, South Korea
| | - Seo Yeong Kim
- Department of Environmental Engineering, College of Engineering, Ajou University, Suwon, South Korea
| | | | - Yung-Hun Yang
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, Republic of Korea.,Institute for Ubiquitous Information Technology and Application, Konkuk University, Seoul, Republic of Korea
| | - Kwon-Young Choi
- Department of Environmental Engineering, College of Engineering, Ajou University, Suwon, South Korea.,Department of Environmental and Safety Engineering, College of Engineering, Ajou University, Suwon, South Korea
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15
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Wang Z, Tan W, Yang D, Zhang K, Zhao L, Xie Z, Xu T, Zhao Y, Wang X, Pan X, Zhang D. Mitigation of soil salinization and alkalization by bacterium-induced inhibition of evaporation and salt crystallization. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 755:142511. [PMID: 33022460 DOI: 10.1016/j.scitotenv.2020.142511] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 09/14/2020] [Accepted: 09/15/2020] [Indexed: 06/11/2023]
Abstract
Soil salinization and alkalization is one of the most devastating environmental problems, threatening the sustainable development of agriculture. Bio-amelioration using microorganisms such as bacteria is a promising method for the remediation of calcareous sodic and saline-sodic soil due to its high efficiency, low cost and environmental-friendly characteristics. In the present study, a salt resistant bacterium, Bacillus subtilis BSN-1, was isolated from arid region in Xinjiang, China, and its effects on salt crystallization during evaporation crystallization of saline-alkali soil solution were examined. It was found that the fermentation products of B. subtilis BSN-1, such as glutamic acid, significantly lowered the pH of saline soil solution because of the ionization of carboxyl. The complexation between Ca2+ and fermentation products inhibited the precipitation of Ca-P compounds as well, since the binding sites supplied for Ca2+ is one or two orders of magnitude than that for HPO42-. Moreover, the increased content of active phosphate is attributed to the chelation and adsorption exerted through carboxyl and amide bonds. These findings demonstrated that Bacillus subtilis BSN-1 suppressed the crystallization of phosphate and therefor increased the content of active phosphate, which may provide a promising solution for amendment and remediation of saline-alkali soil.
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Affiliation(s)
- Ziyan Wang
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Wenjuan Tan
- Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dengqin Yang
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Keqing Zhang
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Liwei Zhao
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Zhengguo Xie
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Tao Xu
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yuwei Zhao
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Xiaonan Wang
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Xiangliang Pan
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China; Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
| | - Daoyong Zhang
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China; Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China.
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16
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Immobilization of Laccase on Magnetic Nanoparticles and Application in the Detoxification of Rice Straw Hydrolysate for the Lipid Production of Rhodotorula glutinis. Appl Biochem Biotechnol 2020; 193:998-1010. [PMID: 33219451 DOI: 10.1007/s12010-020-03465-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 11/09/2020] [Indexed: 10/23/2022]
Abstract
The production of microbial lipid using lignocellulosic agroforestry residues has attracted much attention. But, various inhibitors such as phenols and furans, which are produced during lignocellulosic hydrolysate preparation, are harmful to microbial lipid accumulation. Herein, we developed a novel detoxification strategy of rice straw hydrolysate using immobilized laccase on magnetic Fe3O4 nanoparticles for improving lipid production of Rhodotorula glutinis. Compared with free laccase, the immobilized laccase on magnetic nanoparticles showed better stability, which still retained 76% of original activity at 70 °C and 56% at pH 2 for 6 h. This immobilized laccase was reused to remove inhibitors in acid-pretreated rice straw hydrolysate through recycling with external magnetic field. The results showed that most of phenols, parts of furans, and formic acids could be removed by immobilized laccase after the first batch. Notably, the immobilized laccase exhibited good reusability in repeated batch detoxification. 78.2% phenols, 43.8% furfural, 30.4% HMF, and 16.5% formic acid in the hydrolysate were removed after the fourth batch. Furthermore, these detoxified rice straw hydrolysates, as substrates, were applied to the lipid production of Rhodotorula glutinis. The lipid yield in detoxified hydrolysate was significantly higher than that in undetoxified hydrolysate. These findings suggest that the immobilized laccase on magnetic nanoparticles has a potential to detoxify lignocellusic hydrolysate for improving microbial lipid production.
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17
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Sha Y, Qiu Y, Zhu Y, Sun T, Luo Z, Gao J, Feng X, Li S, Xu H. CRISPRi-Based Dynamic Regulation of Hydrolase for the Synthesis of Poly-γ-Glutamic Acid with Variable Molecular Weights. ACS Synth Biol 2020; 9:2450-2459. [PMID: 32794764 DOI: 10.1021/acssynbio.0c00207] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Poly-γ-glutamic acid (γ-PGA) is a decomposable polymer and has been useful in various industries. The biological functions of γ-PGA are closely linked with its molecular weight (MW). In this study, we established an efficient method to produce variable MWs of γ-PGA from renewable biomass (Jerusalem artichoke) by Bacillus amyloliquefaciens. First, a systematic engineering strategy was proposed in B. amyloliquefaciens to construct an optimal platform for γ-PGA overproduction, in which 24.95 g/L γ-PGA generation was attained. Second, 27.12 g/L γ-PGA with an MW of 20-30 kDa was obtained by introducing a γ-PGA hydrolase (pgdS) into the platform strain constructed above, which reveals a potential correlation between the expression level of pgdS and MW of γ-PGA. Then, a Clustered Regularly Interspaced Short Palindromic Repeats interference (CRISPRi) system was further designed to regulate pgdS expression levels, resulting in γ-PGA with variable MWs. Finally, a combinatorial approach based on three sgRNAs with different repression efficiencies was developed to achieve the dynamic regulation of pgdS and obtain tailor-made γ-PGA production in the MW range of 50-1400 kDa in one strain. This study illustrates a promising approach for the sustainable making of biopolymers with diverse molecular weights in one strain through the controllable expression of hydrolase using the CRISPRi system.
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Affiliation(s)
- Yuanyuan Sha
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, Jiangsu 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, Jiangsu 211816, P. R. China
| | - Yibin Qiu
- Department of Food Science and Technology, College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, P. R. China
| | - Yifan Zhu
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, Jiangsu 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, Jiangsu 211816, P. R. China
| | - Tao Sun
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, Jiangsu 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, Jiangsu 211816, P. R. China
| | - Zhengshan Luo
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, Jiangsu 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, Jiangsu 211816, P. R. China
| | - Jian Gao
- School of Marine and Bioengineering, Yancheng Institute of Technology, Yancheng, Jiangsu 224051, P. R. China
| | - Xiaohai Feng
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, Jiangsu 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, Jiangsu 211816, P. R. China
| | - Sha Li
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, Jiangsu 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, Jiangsu 211816, P. R. China
| | - Hong Xu
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing, Jiangsu 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, Jiangsu 211816, P. R. China
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18
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Sha Y, Huang Y, Zhu Y, Sun T, Luo Z, Qiu Y, Zhan Y, Lei P, Li S, Xu H. Efficient Biosynthesis of Low-Molecular-Weight Poly-γ-glutamic Acid Based on Stereochemistry Regulation in Bacillus amyloliquefaciens. ACS Synth Biol 2020; 9:1395-1405. [PMID: 32353226 DOI: 10.1021/acssynbio.0c00080] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Low-molecular-weight poly-γ-glutamic acid (LMW-γ-PGA) has attracted much attention because of its many potential applications in food, agriculture, medicine, and cosmetics. Enzymatic degradation is an efficient way for the synthesis of LMW-γ-PGA. However, the stereochemistry of γ-PGA limits the degradation of γ-PGA. This study identifies the role of γ-PGA synthase (pgsA) and glutamate racemase (racE) in the regulation of γ-PGA stereochemistry and demonstrates their combinational use for LMW-γ-PGA synthesis. First, the expression of pgsA and racE was enhanced, leading to improvements both in the molecular weight (Mw) and the d-glutamate proportion of γ-PGA. Then, an optimal combination of pgsA, racE, and γ-PGA hydrolase pgdS was constructed by exchanging the gene origins for the synthesis of LMW-γ-PGA. Finally, the Mw of γ-PGA was decreased to 6-8 kDa, which was much lower compared with the case without stereochemistry switching (20-30 kDa). This study provides a novel strategy to control the Mw of γ-PGA based on stereochemistry regulation and lays a solid foundation for synthesis of LMW-γ-PGA.
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Affiliation(s)
- Yuanyuan Sha
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, P. R. China
| | - Yueyuan Huang
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, P. R. China
| | - Yifan Zhu
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, P. R. China
| | - Tao Sun
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, P. R. China
| | - Zhengshan Luo
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, P. R. China
| | - Yibin Qiu
- Department of Food Science and Technology, College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing 210037, P. R. China
| | - Yijing Zhan
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, P. R. China
- Nanjing Shineking Biotech Co., Ltd, Nanjing 210061, P. R. China
| | - Peng Lei
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, P. R. China
| | - Sha Li
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, P. R. China
| | - Hong Xu
- College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, P. R. China
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, P. R. China
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19
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Wang D, Kim H, Lee S, Kim DH, Joe MH. High-level production of poly-γ-glutamic acid from untreated molasses by Bacillus siamensis IR10. Microb Cell Fact 2020; 19:101. [PMID: 32398084 PMCID: PMC7216703 DOI: 10.1186/s12934-020-01361-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 04/30/2020] [Indexed: 01/01/2023] Open
Abstract
Background Poly-γ-glutamic acid (γ-PGA) is a promising biopolymer and has been applied in many fields. Bacillus siamensis SB1001 was a newly isolated poly-γ-glutamic acid producer with sucrose as its optimal carbon source. To improve the utilization of carbon source, and then molasses can be effectively used for γ-PGA production, 60cobalt gamma rays was used to mutate the genes of B. siamensis SB1001. Results Bacillus siamensis IR10 was screened for the production of γ-PGA from untreated molasses. In batch fermentation, 17.86 ± 0.97 g/L γ-PGA was obtained after 15 h, which is 52.51% higher than that of its parent strain. Fed-batch fermentation was performed to further improve the yield of γ-PGA with untreated molasses, yielding 41.40 ± 2.01 g/L of γ-PGA with a productivity of 1.73 ± 0.08 g/L/h. An average γ-PGA productivity of 1.85 g/L/h was achieved in the repeated fed-batch fermentation. This is the first report of such a high γ-PGA productivity. The analysis of the enzyme activities showed that they were affected by the carbon sources, enhanced ICDH and GDH, and decreased ODHC, which are important for γ-PGA production. Conclusion These results suggest that untreated molasses can be used for economical and industrial-scale production of γ-PGA by B. siamensis IR10.![]()
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Affiliation(s)
- Dexin Wang
- Radiation Utilization and Facilities Management Division, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup, 56212, Republic of Korea.,Department of Bioactive Material Sciences, Institute for Molecular Biology and Genetics,Center for Fungal Pathogenesis, Jeonbuk National University, Jeonju, 54896, Republic of Korea
| | - Hyangmi Kim
- Bacteria Research Team, Nakdonggang National Institute of Biological Resources (NNIBR), Sangju, 37242, Republic of Korea
| | - Sungbeom Lee
- Radiation Research Division, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup, 56212, Republic of Korea.,Department of Radiation Science and Technology, University of Science and Technology, Daejeon, 34113, Republic of Korea
| | - Dae-Hyuk Kim
- Department of Bioactive Material Sciences, Institute for Molecular Biology and Genetics,Center for Fungal Pathogenesis, Jeonbuk National University, Jeonju, 54896, Republic of Korea
| | - Min-Ho Joe
- Radiation Utilization and Facilities Management Division, Korea Atomic Energy Research Institute, 29 Geumgu-gil, Jeongeup, 56212, Republic of Korea.
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20
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Poly-(γ-glutamic acid) Production and Optimization from Agro-Industrial Bioresources as Renewable Substrates by Bacillus sp. FBL-2 through Response Surface Methodology. Biomolecules 2019; 9:biom9120754. [PMID: 31756993 PMCID: PMC6995579 DOI: 10.3390/biom9120754] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 11/16/2019] [Accepted: 11/19/2019] [Indexed: 11/16/2022] Open
Abstract
We optimized culture conditions using Bacillus sp. FBL-2 as a poly-(γ-glutamic acid) (PGA) producing strain isolated from cheonggukjang. All experiments were performed under aerobic conditions using a laboratory scale 2.5 L fermentor. We investigated the effects of fermentation parameters (temperature, pH, agitation, and aeration) and medium components (glutamic acid, citric acid, and yeast extract) on poly-(γ-glutamic acid) production, viscosity, and dry cell mass. A non-optimized fermentation method (1.5 vvm, 350 rpm, and 37 °C) yielded PGA, viscosity, and dry cell mass at levels of 100.7 g/L, 483.2 cP, and 3.4 g/L, respectively. L-glutamic acid, citric acid, and yeast extract supplementation enhanced poly-(γ-glutamic acid) production to 175.9 g/L. Additionally, the production of poly-(γ-glutamic acid) from rice bran and wheat bran was assessed using response surface methodology (central composite rotatable design). Agricultural byproducts (rice bran and wheat bran) and H2SO4 were selected as factors, and experiments were performed by combining various component concentrations to determine optimal component concentrations. Our experimentally-derived optimal parameters included 38.6 g/L of rice bran, 0.42% of H2SO4, 28.0 g/L of wheat bran, and 0.32% of H2SO4. Under optimum conditions, rice bran medium facilitated poly-(γ-glutamic acid) production of up to 22.64 g/L, and the use of wheat bran medium yielded up to 14.6 g/L. Based on a validity test using the optimized culture conditions, poly-(γ-glutamic acid) was produced at 47.6 g/L and 36.4 g/L from these respective mediums, and both results were higher than statistically predicted. This study suggests that rice bran can be used as a potential alternative substrate for poly-(γ-glutamic acid) production.
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21
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Sha Y, Sun T, Qiu Y, Zhu Y, Zhan Y, Zhang Y, Xu Z, Li S, Feng X, Xu H. Investigation of Glutamate Dependence Mechanism for Poly-γ-glutamic Acid Production in Bacillus subtilis on the Basis of Transcriptome Analysis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:6263-6274. [PMID: 31088055 DOI: 10.1021/acs.jafc.9b01755] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The development of commercial poly-γ-glutamic acid (γ-PGA) production by glutamate-dependent strains requires understanding the glutamate dependence mechanism in the strains. Here, we first systematically analyzed the response pattern of Bacillus subtilis to glutamate addition by comparative transcriptomics. Glutamate addition induced great changes in intracellular metabolite concentrations and significantly upregulated genes involved in the central metabolic pathways. Subsequent gene overexpression experiments revealed that only the enhancement of glutamate synthesis pathway successfully led to γ-PGA accumulation without glutamate addition, indicating the key role of intracellular glutamate for γ-PGA synthesis in glutamate-dependent strains. Finally, by a combination of metabolic engineering targets, the γ-PGA titer reached 10.21 ± 0.42 g/L without glutamate addition. Exogenous glutamate further enhanced the γ-PGA yield (35.52 ± 0.26 g/L) and productivity (0.74 g/(L h)) in shake-flask fermentation. This work provides insights into the glutamate dependence mechanism in B. subtilis and reveals potential molecular targets for increasing economical γ-PGA production.
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Affiliation(s)
- Yuanyuan Sha
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , People's Republic of China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , People's Republic of China
| | - Tao Sun
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , People's Republic of China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , People's Republic of China
| | - Yibin Qiu
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , People's Republic of China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , People's Republic of China
| | - Yifan Zhu
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , People's Republic of China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , People's Republic of China
| | - Yijing Zhan
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , People's Republic of China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , People's Republic of China
- Nanjing Shineking Biotech Co., Ltd. , Nanjing 210061 , People's Republic of China
| | - Yatao Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , People's Republic of China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , People's Republic of China
| | - Zongqi Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , People's Republic of China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , People's Republic of China
| | - Sha Li
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , People's Republic of China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , People's Republic of China
| | - Xiaohai Feng
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , People's Republic of China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , People's Republic of China
| | - Hong Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering , Nanjing 211816 , People's Republic of China
- College of Food Science and Light Industry , Nanjing Tech University , Nanjing 211816 , People's Republic of China
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22
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Economical production of agricultural γ-polyglutamic acid using industrial wastes by Bacillus subtilis. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.03.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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23
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Kim J, Lee JM, Jang WJ, Park HD, Kim Y, Kim C, Kong I. Efficient production of poly γ‐
d
‐glutamic acid from the bloom‐forming green macroalgae,
Ulva
sp., by
Bacillus
sp. SJ‐10. Biotechnol Bioeng 2019; 116:1594-1603. [DOI: 10.1002/bit.26966] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 02/12/2019] [Accepted: 03/14/2019] [Indexed: 01/26/2023]
Affiliation(s)
- Jang‐Ho Kim
- Department of Biotechnology, College of Fisheries SciencePukyong National UniversityBusan Republic of Korea
| | - Jong Min Lee
- Industrial Biomaterials Research CenterKorea Research Institute of Bioscience and Biotechnology (KRIBB)Daejeon Korea
| | - Won Je Jang
- Department of Biotechnology, College of Fisheries SciencePukyong National UniversityBusan Republic of Korea
| | - Hae Dae Park
- Department of Biotechnology, College of Fisheries SciencePukyong National UniversityBusan Republic of Korea
| | - Young‐Ok Kim
- Biotechnology Research DivisionNational Institute of Fisheries ScienceBusan Republic of Korea
| | - Chang‐Hoon Kim
- Department of Marine Biomaterials & AquaculturePukyong National UniversityBusan Republic of Korea
| | - In‐Soo Kong
- Department of Biotechnology, College of Fisheries SciencePukyong National UniversityBusan Republic of Korea
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24
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Stimulatory effects of amino acids on γ-polyglutamic acid production by Bacillus subtilis. Sci Rep 2018; 8:17934. [PMID: 30560878 PMCID: PMC6298950 DOI: 10.1038/s41598-018-36439-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 11/20/2018] [Indexed: 11/08/2022] Open
Abstract
This paper is about study to increase the γ-PGA yield by developing new methods. The effect of various amino acids on production of γ-PGA by Bacillus subtilis Z15 was investigated. The γ-PGA yield was increased 23.18%, 12.15% and 31.46%, respectively, with 3 g/L aspartic acid (0 h), 1.5 g/L phenylalanine (0 h) and 7 g/L glutamic acid (24 h). Additonally, crude extract of glutamic acid after isoelectric crystallization (CEGA)could be a replacement for glutamate for γ-PGA production. Then, response surface methodology (RSM) was used for further optimization. The final media ingredient of amino acids were obtained as follow: CEGA 9 g/L, aspartic acid 4 g/L, phenylalanine 1.55 g/L. By applying this receipt in 5-L bioreactor, the γ-PGA yield reached 42.92 ± 0.23 g/L after 44 h, which is 63.1% higher than the control without amino acids for production. In addition, amino acids could shorten the lag phase and the average fermentation time (44 h versus 48 h). Fermentation with amino acids addition can be an positive option for γ-PGA production.
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25
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Hsueh YH, Huang KY, Kunene SC, Lee TY. Poly-γ-glutamic Acid Synthesis, Gene Regulation, Phylogenetic Relationships, and Role in Fermentation. Int J Mol Sci 2017; 18:E2644. [PMID: 29215550 PMCID: PMC5751247 DOI: 10.3390/ijms18122644] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 12/01/2017] [Accepted: 12/04/2017] [Indexed: 02/03/2023] Open
Abstract
Poly-γ-glutamic acid (γ-PGA) is a biodegradable biopolymer produced by several bacteria, including Bacillus subtilis and other Bacillus species; it has good biocompatibility, is non-toxic, and has various potential biological applications in the food, pharmaceutical, cosmetic, and other industries. In this review, we have described the mechanisms of γ-PGA synthesis and gene regulation, its role in fermentation, and the phylogenetic relationships among various pgsBCAE, a biosynthesis gene cluster of γ-PGA, and pgdS, a degradation gene of γ-PGA. We also discuss potential applications of γ-PGA and highlight the established genetic recombinant bacterial strains that produce high levels of γ-PGA, which can be useful for large-scale γ-PGA production.
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Affiliation(s)
- Yi-Huang Hsueh
- Graduate School of Biotechnology and Bioengineering, Yuan Ze University, Taoyuan city 32003, Taiwan.
| | - Kai-Yao Huang
- Department of Computer Science and Engineering, Yuan Ze University, Taoyuan city 32003, Taiwan.
- Department of Medical Research, Hsinchu Mackay Memorial Hospital, Hsinchu city 300, Taiwan.
| | - Sikhumbuzo Charles Kunene
- Graduate School of Biotechnology and Bioengineering, Yuan Ze University, Taoyuan city 32003, Taiwan.
| | - Tzong-Yi Lee
- Department of Computer Science and Engineering, Yuan Ze University, Taoyuan city 32003, Taiwan.
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26
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Conformations and molecular interactions of poly-γ-glutamic acid as a soluble microbial product in aqueous solutions. Sci Rep 2017; 7:12787. [PMID: 28986570 PMCID: PMC5630630 DOI: 10.1038/s41598-017-13152-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 09/19/2017] [Indexed: 12/02/2022] Open
Abstract
Soluble microbial products (SMPs) are of significant concern in the natural environment and in engineered systems. In this work, poly-γ-glutamic acid (γ-PGA), which is predominantly produced by Bacillus sp., was investigated in terms of pH-induced conformational changes and molecular interactions in aqueous solutions; accordingly, its sedimentation coefficient distribution and viscosity were also elucidated. Experimental results indicate that pH has a significant impact on the structure and molecular interactions of γ-PGA. The conformation of the γ-PGA acid form (γ-PGA-H) is rod-like while that of the γ-PGA sodium form (γ-PGA-Na) is sphere-like. The transformation from α-helix to random coil in the γ-PGA secondary structure is primarily responsible for this shape variation. The intramolecular hydrogen bonds in the γ-PGA-H structure decrease and intramolecular electrostatic repulsion increases as pH increases; however, the sedimentation coefficient distributions of γ-PGA are dependent on intermolecular interactions rather than intramolecular interactions. Concentration has a more substantial effect on intermolecular electrostatic repulsion and chain entanglement at higher pH values. Consequently, the sedimentation coefficient distributions of γ-PGA shift significantly at pH 8.9 from 0.1 to 1.0 g/L, and the viscosity of γ-PGA (5% w/v) significantly increases as pH increases from 2.3 to 6.0.
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27
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Qiu Y, Sha Y, Zhang Y, Xu Z, Li S, Lei P, Xu Z, Feng X, Xu H. Development of Jerusalem artichoke resource for efficient one-step fermentation of poly-(γ-glutamic acid) using a novel strain Bacillus amyloliquefaciens NX-2S. BIORESOURCE TECHNOLOGY 2017; 239:197-203. [PMID: 28521229 DOI: 10.1016/j.biortech.2017.05.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 04/27/2017] [Accepted: 05/01/2017] [Indexed: 06/07/2023]
Abstract
This study aimed to develop non-food fermentation for the cost-effective production of poly-(γ-glutamic acid) (γ-PGA) using a novel strain of Bacillus amyloliquefaciens NX-2S. The new isolate assimilated inulin more efficiently than other carbohydrates from Jerusalem artichoke, without hydrolytic treatment. To investigate the effect of inulin on γ-PGA production, the transcript levels of γ-PGA synthetase genes (pgsB, pgsC, pgsA), regulatory genes (comA, degQ, degS), and the glutamic acid biosynthesis gene (glnA) were analyzed; inulin addition upregulated these key genes. Without exogenous glutamate, strain NX-2S could produce 6.85±0.22g/L of γ-PGA during fermentation. Exogenous glutamate greatly enhances the γ-PGA yield (39.4±0.38g/L) and productivity (0.43±0.05g/L/h) in batch fermentation. Our study revealed a potential method of non-food fermentation to produce high-value products.
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Affiliation(s)
- Yibin Qiu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Yuanyuan Sha
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Yatao Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Zongqi Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Sha Li
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Peng Lei
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Zheng Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Xiaohai Feng
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Hong Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
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28
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Jiang Y, Tang B, Xu Z, Liu K, Xu Z, Feng X, Xu H. Improvement of poly-γ-glutamic acid biosynthesis in a moving bed biofilm reactor by Bacillus subtilis NX-2. BIORESOURCE TECHNOLOGY 2016; 218:360-366. [PMID: 27376835 DOI: 10.1016/j.biortech.2016.06.103] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 06/19/2016] [Accepted: 06/20/2016] [Indexed: 06/06/2023]
Abstract
The production of poly-γ-glutamic acid (γ-PGA) by Bacillus subtilis NX-2 using a moving bed biofilm reactor (MBBR) system was tested for the first time in this study. Polypropylene TL-2 was chosen as a suitable carrier, and γ-PGA concentration of 42.7±0.86g/L and productivity of 0.59±0.06g/(Lh) were obtained in batch fermentation. After application of the strategy of dissolved oxygen (DO)-stat feeding, higher γ-PGA concentration and productivity were achieved than with glucose feedback feeding. Finally, the repeated fed-batch cultures implemented in the MBBR system showed high stability, and the maximal γ-PGA concentration and productivity of 74.2g/L and 1.24g/(Lh) were achieved, respectively. In addition, the promotion of oxygen transfer by an MBBR carrier was well explained by a computational fluid dynamics (CFD) simulation. These results suggest that an MBBR system could be applied to large-scale γ-PGA production.
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Affiliation(s)
- Yongxiang Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Bao Tang
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Zongqi Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Kun Liu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Zheng Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Xiaohai Feng
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
| | - Hong Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
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29
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Abraham A, Mathew AK, Sindhu R, Pandey A, Binod P. Potential of rice straw for bio-refining: An overview. BIORESOURCE TECHNOLOGY 2016; 215:29-36. [PMID: 27067674 DOI: 10.1016/j.biortech.2016.04.011] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 04/01/2016] [Accepted: 04/02/2016] [Indexed: 05/24/2023]
Abstract
The biorefinery approach for the production of fuels and chemicals is gaining more and more attraction in recent years. The major advantages of biorefineries are the generation of multiple products with complete utilization of biomass with zero waste generation. Moreover the process will be economically viable when it targets low volume high value products in addition to high volume low value products like bioethanol. The present review discuss about the potential of rice straw based biorefinery. Since rice is a major staple food for many Asian countries, the utilization of the rice straw residue for fuel and chemicals would be very economical. The review focuses the availability and the potential of this residue for the production of fuel and other high value chemicals.
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Affiliation(s)
- Amith Abraham
- Biotechnology Division, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India
| | - Anil Kuruvilla Mathew
- Biotechnology Division, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India
| | - Raveendran Sindhu
- Biotechnology Division, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India
| | - Ashok Pandey
- Biotechnology Division, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India
| | - Parameswaran Binod
- Biotechnology Division, National Institute for Interdisciplinary Science and Technology, CSIR, Trivandrum 695 019, India.
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30
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Luo Z, Guo Y, Liu J, Qiu H, Zhao M, Zou W, Li S. Microbial synthesis of poly-γ-glutamic acid: current progress, challenges, and future perspectives. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:134. [PMID: 27366207 PMCID: PMC4928254 DOI: 10.1186/s13068-016-0537-7] [Citation(s) in RCA: 154] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 05/31/2016] [Indexed: 05/22/2023]
Abstract
Poly-γ-glutamic acid (γ-PGA) is a naturally occurring biopolymer made from repeating units of l-glutamic acid, d-glutamic acid, or both. Since some bacteria are capable of vigorous γ-PGA biosynthesis from renewable biomass, γ-PGA is considered a promising bio-based chemical and is already widely used in the food, medical, and wastewater industries due to its biodegradable, non-toxic, and non-immunogenic properties. In this review, we consider the properties, biosynthetic pathway, production strategies, and applications of γ-PGA. Microbial biosynthesis of γ-PGA and the molecular mechanisms regulating production are covered in particular detail. Genetic engineering and optimization of the growth medium, process control, and downstream processing have proved to be effective strategies for lowering the cost of production, as well as manipulating the molecular mass and conformational/enantiomeric properties that facilitate screening of competitive γ-PGA producers. Finally, future prospects of microbial γ-PGA production are discussed in light of recent progress, challenges, and trends in this field.
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Affiliation(s)
- Zhiting Luo
- />College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004 China
| | - Yuan Guo
- />National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Sciences, Nanning, 530004 China
| | - Jidong Liu
- />College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004 China
| | - Hua Qiu
- />College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004 China
| | - Mouming Zhao
- />College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004 China
| | - Wei Zou
- />College of Bioengineering, Sichuan University of Science and Engineering, Zigong, 643000 Sichuan China
| | - Shubo Li
- />College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004 China
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