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Liu P, Chen L, Hamoud YA, Zheng J, Chang T, Ali J, Huang H, Shaghaleh H. Ameliorative effect of poly-γ-glutamic acid biopreparation on coastal saline soil. Heliyon 2024; 10:e36762. [PMID: 39263153 PMCID: PMC11388776 DOI: 10.1016/j.heliyon.2024.e36762] [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: 03/12/2024] [Revised: 08/21/2024] [Accepted: 08/21/2024] [Indexed: 09/13/2024] Open
Abstract
To investigate the effect of poly-γ-glutamic acid (γ-PGA) biopreparation on ameliorating coastal saline soil, three treatments were established: soil salt washed treatment (CK), soil salt washed with added γ-PGA (PGA), soil salt washed with added γ-PGA biopreparation (PGAB). This study determined the effects of γ-PGA on coastal saline soil by analyzing soil aggregate, soil evaporation, soil vertical water and salt distribution, and soil cation content, soil pH, soil nutrient content and soil microorganism quantity. Results showed that γ-PGA had an ameliorative effect on saline soil, with the PGAB treatment exhibiting the most pronounced ameliorative effect compared to CK. Adding PGAB reduced soil evaporation by 30.45 %, soil salt content by 27.91 %, meanwhile increasing plant height by 33.86 %, plant fresh weight by 98.54 %, soil aggregate diameter by 6.68 times, soil water content by 26.47 % (P < 0.05). Additionally, soil total nitrogen was increased by 50.0 % in PGAB treatment, and available nitrogen and phosphorus contents were increased by 1.68 times and 85.83 % (P < 0.05), respectively. Populations of soil-culturable bacteria and fungi of PGAB treatment increased by 65.96 % and 1.23 times, respectively (P < 0.05). After salt-washing process, adding PGAB improved soil physicochemical properties, which altered the ecological environment of rhizosphere soil and promoted plant growth. The results can provide a practical approach for ameliorating coastal saline soils.
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Affiliation(s)
- Pei Liu
- College of Agricultural Science and Engineering, Hohai University, Nanjing, 210098, China
| | - Lihua Chen
- College of Agricultural Science and Engineering, Hohai University, Nanjing, 210098, China
| | - Yousef Alhaj Hamoud
- College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, China
| | - Jinhai Zheng
- College of Harbour, Coastal and Offshore Engineering, Hohai University, Nanjing, 210098, China
| | - Tingting Chang
- College of Agricultural Science and Engineering, Hohai University, Nanjing, 210098, China
| | - Jawad Ali
- College of Agricultural Science and Engineering, Hohai University, Nanjing, 210098, China
| | - He Huang
- College of Agricultural Science and Engineering, Hohai University, Nanjing, 210098, China
- College of Forestry, Nanjing Forestry University, Nanjing, 210037, China
| | - Hiba Shaghaleh
- College of Environment, Hohai University, Nanjing, 210098, China
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Jing B, Shi W, Wang Y. Poly-γ-glutamic acid enhanced the yield and photosynthesis of soybeans by adjusting soil aggregates and water distribution. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2024; 104:6884-6892. [PMID: 38591419 DOI: 10.1002/jsfa.13520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 02/20/2024] [Accepted: 04/03/2024] [Indexed: 04/10/2024]
Abstract
BACKGROUND Poly-γ-glutamic acid (γ-PGA) is employed extensively in agriculture to enhance soil water retention; however, the underlying mechanism by which γ-PGA improves soil structure and soybean productivity in arid regions remains poorly understood. A micro-scale field experiment was conducted in the arid region of northwest China, employing five concentrations of γ-PGA to investigate its impacts on soybean yield, photosynthesis, and water-use efficiency, as well as soil aggregates and water distribution. The five levels of γ-PGA were 0 (CK), 10 (P1), 20 (P2), 40 (P3), and 80 kg ha-1 (P4). RESULTS The results demonstrated that the application of γ-PGA significantly improved soybean yield, photosynthesis, and chlorophyll content. It resulted in a decrease in soil aggregate content with a maximum diameter of less than 0.053 mm and an increase in the stability of soil aggregates in the uppermost layer of the soil (0-30 cm). The application of γ-PGA significantly increased soil water content, particularly in the uppermost layer of the soil, and effectively reduced water consumption and improving water use efficiency in soybeans. Overall, the P3 treatment exhibited the most pronounced improvement of soybean yield, photosynthesis, water-use efficiency, as well as distribution of soil aggregates and water. The correlation matrix heatmap also revealed a strong correlation between improvement of soybean yield or photosynthesis at various γ-PGA application levels and the enhancement of soil stability or soil water content. CONCLUSION The multivariate regression analysis revealed that an optimal application level of 46 kg ha-1 γ-PGA could enhance effectively both yield and water use efficiency of soybean in the arid region of northwest China. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Bo Jing
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, China
| | - Wenjuan Shi
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, China
| | - Ying Wang
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, China
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Fu Y, Li G, Wang S, Dai Z. Effect of sesame cake fertilizer with γ-PGA on soil nutrient, water and nitrogen use efficiency. Sci Rep 2024; 14:18669. [PMID: 39134660 PMCID: PMC11319793 DOI: 10.1038/s41598-024-69650-7] [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: 03/26/2024] [Accepted: 08/07/2024] [Indexed: 08/15/2024] Open
Abstract
γ-polyglutamic acid (γ-PGA), as an environmentally sustainable material, is extensive applied in agriculture for enhancing water and fertilizer utilization efficiency, augmenting crop yield, and ameliorating soil conditions. However, the effect of γ-PGA in conjunction with sesame cake fertilizer on the soil environment remains uncertain.The aim of this study is to investigate the effect of γ-PGA on soil nutrients, water use efficiency (WUE) and nitrogen use efficiency (NUE), and maize yield across various levels of sesame cake fertilizer. Additionally, the study seeks to identify the optimal ratio to establish a theoretical and practical foundation for sustainable agricultural development and the promotion of ecological agriculture. Through field experiments, nine treatments were established, comprising three levels of sesame cake fertilizer application rates (B1 = 900 kg/hm2 for low fertility, B2 = 1100 kg/hm2 for medium fertility, and B3 = 1300 kg/hm2 for high fertility) and three levels of γ-PGA application rates (R1 = 200 kg/hm2, R2 = 400 kg/hm2, and R3 = 600 kg/hm2). The results can be outlined as follows: (1) When γ-PGA application rate increased, total nitrogen (TN) exhibited a synergistic effect under B1 treatment, but an antagonistic effect under B2 and B3 treatments. At the 6-leaf stage (V6), 12-leaf stage (V12), and tasseling stage (VT), available phosphorus (AP) exhibited antagonistic effects. However, at the filling stage (R2) and maturity stage (R6), AP in B1 and B2 treatments at various depths underwent partial transformation into a synergistic effect. The levels of available potassium exhibited a notable antagonistic effect, leading to a decrease in harvest index (HI). B2 treatment demonstrated superior results compared to the B1 and B3 treatments, with the highest levels observed under B2R1 treatment; (2) TN content in the 0-40 cm soil layer increased during the filling period, and it was uniformly distributed in the 40-60 cm soil layer. When the soil AP was located in the 0-60 cm soil layer, there was an increase in AP content during the mature period. Following the tasseling period, different treatments exhibited varying patterns of increase in response to the presence of potassium within the 0-60 cm soil layer. Consequently, in cases where the sesame cake fertilizer content is low, the interaction between γ-PGA can compensate for the deficiency of fertilizer, thereby enhancing water and nitrogen utilization efficiency. The optimal fertilization strategy for enhancing soil nutrient distribution, WUE and NUE, and yield is proposed to be the application of 1100 kg/hm2 sesame cake fertilizer and 200 kg/hm2 γ-PGA.
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Affiliation(s)
- Yuliang Fu
- School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China
| | - Gang Li
- School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China
| | - Songlin Wang
- School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China.
| | - Zhiguang Dai
- College of Agricultural Equipment Engineering, Henan Universityof Science and Technology, Luoyang, China
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Sun X, Cai Y, Wang D. Enhanced Poly-γ-Glutamic Acid Production by a Newly Isolated Bacillus halotolerans F29. J Microbiol 2024; 62:695-707. [PMID: 39164498 DOI: 10.1007/s12275-024-00153-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/20/2024] [Accepted: 06/09/2024] [Indexed: 08/22/2024]
Abstract
Poly-γ-glutamic acid (γ-PGA) is a promising biopolymer for various applications. In this study, we isolated a novel γ-PGA-producing strain, Bacillus halotolerans F29. The one-factor-at-a-time method was used to investigate the influence of carbon sources, nitrogen sources, and culture parameters on γ-PGA production. The optimal carbon and nitrogen sources were sucrose and (NH4)2SO4, respectively. The optimal culture conditions for γ-PGA production were determined to be 37 °C and a pH of 5.5. Response surface methodology was used to determine the optimum medium components: 77.6 g/L sucrose, 43.0 g/L monosodium glutamate, and 2.2 g/L K2HPO4. The γ-PGA titer increased significantly from 8.5 ± 0.3 g/L to 20.7 ± 0.7 g/L when strain F29 was cultivated in the optimized medium. Furthermore, the γ-PGA titer reached 50.9 ± 1.5 g/L with a productivity of 1.33 g/L/h and a yield of 2.23 g of γ-PGA/g of L-glutamic acid with the optimized medium in fed-batch fermentation. The maximum γ-PGA titer reached 45.3 ± 1.1 g/L, with a productivity of 1.06 g/L/h when molasses was used as a carbon source. It should be noted that the γ-PGA yield in this study was the highest of all reported studies, indicating great potential for the industrial production of γ-PGA.
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Affiliation(s)
- Xiaorong Sun
- Institute of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, People's Republic of China
| | - Yaoyu Cai
- Lab of Biorefinery, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210, People's Republic of China.
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
| | - Dexin Wang
- Lab of Biorefinery, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210, People's Republic of China.
- CAS Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China.
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Hong L, Wei L, Fanglan G, Jiao L, Shiheng T, Hong Y, Yao R, Xinyue G, Can Y. Unveiling the regulatory mechanism of poly-γ-glutamic acid on soil characteristics under drought stress through integrated metagenomics and metabolomics analysis. Front Microbiol 2024; 15:1387223. [PMID: 38751715 PMCID: PMC11094619 DOI: 10.3389/fmicb.2024.1387223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 04/17/2024] [Indexed: 05/18/2024] Open
Abstract
It is of utmost importance to understand the characteristics and regulatory mechanisms of soil in order to optimize soil management and enhance crop yield. Poly-γ-glutamic acid (γ-PGA), a stress-resistant amino acid polymer, plays a crucial role in plant drought stress resistance. However, little is known about the effects of γ-PGA on soil characteristics during drought treatments. In this study, the effects of different forms of γ-PGA on soil texture and basic physical and chemical properties under short-term drought conditions were investigated. Furthermore, the impact of γ-PGA on the microbial community and metabolic function of maize was analyzed. Under drought conditions, the introduction of γ-PGA into the soil resulted in notable improvements in the mechanical composition ratio and infiltration capacity of the soil. Concurrently, this led to a reduction in soil bulk density and improved soil organic matter content and fertility. Additionally, metagenomic analysis revealed that under drought conditions, the incorporation of γ-PGA into the soil enhanced the soil microbiota structure. This shift led to the predominance of bacteria that are crucial for carbon, nitrogen, and phosphorus cycles in the soil. Metabolomics analysis revealed that under drought treatment, γ-PGA affected soil metabolic patterns, with a particular focus on alterations in amino acid and vitamin metabolism pathways. Correlation analysis between the soil metagenome and metabolites showed that microorganisms played a significant role in metabolite accumulation. These results demonstrated that γ-PGA could improve soil characteristics under drought conditions and play an important role in soil microorganisms and microbial metabolism, providing further insights into the changes in soil characteristics under drought conditions.
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Affiliation(s)
- Li Hong
- Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources (Ministry of Education), Sichuan Normal University, Chengdu, China
- College of Life Sciences, Sichuan Normal University, Chengdu, China
| | - Li Wei
- Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources (Ministry of Education), Sichuan Normal University, Chengdu, China
- College of Life Sciences, Sichuan Normal University, Chengdu, China
| | - Ge Fanglan
- Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources (Ministry of Education), Sichuan Normal University, Chengdu, China
- College of Life Sciences, Sichuan Normal University, Chengdu, China
| | - Li Jiao
- Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources (Ministry of Education), Sichuan Normal University, Chengdu, China
- College of Life Sciences, Sichuan Normal University, Chengdu, China
| | - Tu Shiheng
- Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources (Ministry of Education), Sichuan Normal University, Chengdu, China
- College of Life Sciences, Sichuan Normal University, Chengdu, China
| | - Yang Hong
- Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources (Ministry of Education), Sichuan Normal University, Chengdu, China
- College of Life Sciences, Sichuan Normal University, Chengdu, China
| | - Ren Yao
- Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources (Ministry of Education), Sichuan Normal University, Chengdu, China
- College of Life Sciences, Sichuan Normal University, Chengdu, China
| | - Gong Xinyue
- Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources (Ministry of Education), Sichuan Normal University, Chengdu, China
- College of Life Sciences, Sichuan Normal University, Chengdu, China
| | - Yao Can
- Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources (Ministry of Education), Sichuan Normal University, Chengdu, China
- College of Life Sciences, Sichuan Normal University, Chengdu, China
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Guo Y, Liu Y, Yang Z, Chen G, Liang Z, Zeng W. Enhanced Production of Poly-γ-glutamic Acid by Bacillus subtilis Using Stage-controlled Fermentation and Viscosity Reduction Strategy. Appl Biochem Biotechnol 2024; 196:1527-1543. [PMID: 37432638 DOI: 10.1007/s12010-023-04644-1] [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] [Accepted: 07/01/2023] [Indexed: 07/12/2023]
Abstract
In this study, the production of poly-γ-glutamic acid (PGA) by Bacillus subtilis using stage-controlled fermentation and viscosity reduction strategy was investigated in detail. Based on the single-factor optimization experiment, temperature (42 °C and 37 °C), pH (7.0 and uncontrolled), aeration rate (1.2 vvm and 1.0 vvm), and agitation speed (700 rpm and 500 rpm) were selected for the two-stage controlled fermentation (TSCF). The time points for the TSCF of temperature, pH, aeration rate, and agitation speed were set at 18.52 h, 2.82 h, 5.92 h, and 3.62 h, respectively, based on the kinetic analysis. A PGA titer of 19.79 ~ 22.17 g/L was obtained from the TSCF, which did not increase significantly than that (21.25 ± 1.26 g/L) of non-stage controlled fermentation (NSCF). This may be due to the high viscosity and low dissolved oxygen of the PGA fermentation broth. Thus, the TSCF combined with a viscosity reduction strategy was developed to further improve the production of PGA. The PGA titer reached 25.00 ~ 30.67 g/L, which increased by 17.66 ~ 32.94% to that of NSCF. This study provided a valuable reference for the development of process control strategies for high-viscosity fermentation systems.
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Affiliation(s)
- Yin Guo
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Microorganism and Enzyme Research Center of Engineering Technology, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Yuanyuan Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Microorganism and Enzyme Research Center of Engineering Technology, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Zejian Yang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Microorganism and Enzyme Research Center of Engineering Technology, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Guiguang Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Microorganism and Enzyme Research Center of Engineering Technology, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Zhiqun Liang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Microorganism and Enzyme Research Center of Engineering Technology, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China
| | - Wei Zeng
- Key Laboratory of Biochemistry and Molecular Biology (Guilin Medical University), Education Department of Guangxi Zhuang Autonomous Region, School of Intelligent Medicine and Biotechnology, Guilin Medical University, 1 Zhiyuan Road, Guilin, 541199, Guangxi, China.
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Microorganism and Enzyme Research Center of Engineering Technology, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning, 530004, Guangxi, China.
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Jing B, Shi W, Liu L, Wang Y. Poly-γ-glutamic acid improved biological nitrogen fixation, water-nitrogen productivity, and nitrate residue in cotton/soybean intercropping. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2023; 103:7284-7292. [PMID: 37378640 DOI: 10.1002/jsfa.12814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/25/2023] [Accepted: 06/28/2023] [Indexed: 06/29/2023]
Abstract
BACKGROUND Poly-γ-glutamic acid (γ-PGA) can promote crop growth and improve soil properties efficiently. However, the optimal application rate of γ-PGA in legume/non-legume intercropping systems is still unclear. A potted experiment was conducted to investigate the effects of five γ-PGA rates (0%, 0.1%, 0.2%, 0.3%, and 0.4%, represented by CK, P1, P2, P3, and P4, respectively) on biological nitrogen (N) fixation (BNF), water-N productivity, and nitrate distribution in a cotton/soybean intercropping system. RESULTS The results showed that the growth indicators (plant height, stem diameter, leaf area index, root dry weight, root length) of cotton and soybean increased first and then decreased with increasing γ-PGA rates, and all growth indicators of cotton and soybean showed peaks in P3 and P2 treatments. The stable 15 N isotope method indicated that γ-PGA promoted the BNF capacity of soybean and soil. In particular, the percentage of N derived from the atmosphere (Ndfa) in soybean reached 61.94% in the P2 treatment. Poly-γ-glutamic acid improved the water-N productivity, and the total N partial factor productivity (NPFP) and water productivity (WP) in P3 treatment increased by 23.80% and 43.86% compared with the CK treatment. The γ-PGA mitigation of potential nitrate residue also decreased first and then increased with increasing γ-PGA rates. CONCLUSION Multivariate regression analysis showed that 0.22% of the optimal γ-PGA application rate could obtain a higher yield and water-N productivity in cotton/soybean intercropping system simultaneously. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Bo Jing
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, China
| | - Wenjuan Shi
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, China
| | - Lu Liu
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, China
| | - Ying Wang
- State Key Laboratory of Eco-Hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an, China
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Wang D, Fu X, Zhou D, Gao J, Bai W. Engineering of a newly isolated Bacillus tequilensis BL01 for poly-γ-glutamic acid production from citric acid. Microb Cell Fact 2022; 21:276. [PMID: 36581997 PMCID: PMC9798646 DOI: 10.1186/s12934-022-01994-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 12/14/2022] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Poly γ-glutamic acid (γ-PGA) is a promising biopolymer for various applications. For glutamic acid-independent strains, the titer of γ-PGA is too low to meet the industrial demand. In this study, we isolated a novel γ-PGA-producing strain, Bacillus tequilensis BL01, and multiple genetic engineering strategies were implemented to improve γ-PGA production. RESULTS First, the one-factor-at-a-time method was used to investigate the influence of carbon and nitrogen sources and temperature on γ-PGA production. The optimal sources of carbon and nitrogen were sucrose and (NH4)2SO4 at 37 °C, respectively. Second, the sucA, gudB, pgdS, and ggt genes were knocked out simultaneously, which increased the titer of γ-PGA by 1.75 times. Then, the titer of γ-PGA increased to 18.0 ± 0.3 g/L by co-overexpression of the citZ and pyk genes in the mutant strain. Furthermore, the γ-PGA titer reached 25.3 ± 0.8 g/L with a productivity of 0.84 g/L/h and a yield of 1.50 g of γ-PGA/g of citric acid in fed-batch fermentation. It should be noted that this study enables the synthesis of low (1.84 × 105 Da) and high (2.06 × 106 Da) molecular weight of γ-PGA by BL01 and the engineering strain. CONCLUSION The application of recently published strategies to successfully improve γ-PGA production for the new strain B. tequilensis BL01 is reported. The titer of γ-PGA increased 2.17-fold and 1.32-fold compared with that of the wild type strain in the flask and 5 L fermenter. The strain shows excellent promise as a γ-PGA producer compared with previous studies. Meanwhile, different molecular weights of γ-PGA were obtained, enhancing the scope of application in industry.
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Affiliation(s)
- Dexin Wang
- grid.9227.e0000000119573309CAS Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China ,National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308 China
| | - Xiaoping Fu
- grid.9227.e0000000119573309CAS Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China ,National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308 China
| | - Dasen Zhou
- grid.413109.e0000 0000 9735 6249College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457 China
| | - Jiaqi Gao
- grid.9227.e0000000119573309CAS Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China ,National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308 China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, 19A Yuquan Road, Shijingshan District, Beijing, 100049 China
| | - Wenqin Bai
- grid.9227.e0000000119573309CAS Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China ,National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308 China
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