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Wang Y, Gao M, Zhu S, Li Z, Zhang T, Jiang Y, Zhu L, Zhan X. Glycerol-driven adaptive evolution for the production of low-molecular-weight Welan gum: Characterization and activity evaluation. Carbohydr Polym 2024; 339:122292. [PMID: 38823937 DOI: 10.1016/j.carbpol.2024.122292] [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: 03/24/2024] [Revised: 05/11/2024] [Accepted: 05/16/2024] [Indexed: 06/03/2024]
Abstract
Through adaptive laboratory evolution (ALE) of Sphingomonas sp. ATCC 31555, fermentation for production of low-molecular-weight welan gum (LMW-WG) was performed using glycerol as sole carbon source. During ALE, GPC-MALS analysis revealed a gradual decrease in WG molecular weight with the increase of adaptation cycles, accompanied by changes in solution conformation. LMW-WG was purified and structurally analyzed using GPC-MALS, monosaccharide composition analysis, infrared spectroscopy, NMR analysis, atomic force microscopy, and scanning electron microscopy. Subsequently, LMW-WG obtains hydration, transparency, antioxidant activity, and rheological properties. Finally, an in vitro simulation colon reactor was used to evaluate potential prebiotic properties of LMW-WG as dietary fiber. Compared with WG produced using sucrose as substrate, LMW-WG exhibited a fourfold reduction in molecular weight while maintaining moderate viscosity. Structurally, L-Rha nearly completely replaced L-Man. Furthermore, LMW-WG demonstrated excellent hydration, antioxidant activity, and high transparency. It also exhibited resistance to saliva and gastrointestinal digestion, showcasing a favorable colonization effect on Bifidobacterium, making it a promising symbiotic agent.
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Affiliation(s)
- Yuying Wang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Minjie Gao
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Shengyong Zhu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Zhitao Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Tiantian Zhang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Yun Jiang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Li Zhu
- A & F Biotech. Ltd., Burnaby, BC V5A3P6, Canada
| | - Xiaobei Zhan
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
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2
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Erkorkmaz BA, Kırtel O, Abaramak G, Nikerel E, Öner ET. UV and Chemically Induced Halomonas smyrnensis Mutants for Enhanced Levan Productivity. J Biotechnol 2022; 356:19-29. [PMID: 35914617 DOI: 10.1016/j.jbiotec.2022.07.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 07/14/2022] [Accepted: 07/28/2022] [Indexed: 11/29/2022]
Abstract
Halomonas smyrnensis AAD6T is a moderately halophilic bacterium proven to be a powerful biotechnological tool with its ability to accumulate valuable biopolymers such as levan and poly(3-hydroxybutyrate) (PHB). Levan is a fructose homopolymer with β-2,6 fructofuranosidic linkages on the polymer backbone, and its distinctive applications in various industries such as food, pharmaceutical, medical, and chemical have been well-defined. On the other hand, PHB is a promising raw material to produce biodegradable plastics. Although it was shown in our previous studies that H. smyrnensis AAD6T exhibits one of the highest conversion yields of sucrose to levan reported to date, novel strategies are required to overcome high costs of levan production. In this study, we aimed at increasing levan productivity of H. smyrnensis AAD6T cultures using random mutagenesis techniques combined (i.e., ethyl methanesulfate treatment and/or ultraviolet irradiation). After several consecutive treatments, mutant strains BAE2, BAE5 and BAE6 were selected as efficient levan producers, as BAE2 standing out as the most efficient one not only in sucrose utilization and levan production rates, but also in final PHB concentrations. The mutants' whole genome sequences were analysed to determine the mutations occurred. Several mutations in genes related to central carbon metabolism and osmoregulation were found. Our results suggest that random mutagenesis can be a facile and efficient strategy to enhance the performance of extremophiles in adverse conditions.
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Affiliation(s)
- Burak Adnan Erkorkmaz
- Industrial Biotechnology and Systems Biology Research Group-IBSB, Department of Bioengineering, Marmara University, 34722 Istanbul, Turkey; Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Onur Kırtel
- Industrial Biotechnology and Systems Biology Research Group-IBSB, Department of Bioengineering, Marmara University, 34722 Istanbul, Turkey
| | - Gülbahar Abaramak
- Industrial Biotechnology and Systems Biology Research Group-IBSB, Department of Bioengineering, Marmara University, 34722 Istanbul, Turkey
| | - Emrah Nikerel
- Department of Genetics and Bioengineering, Yeditepe University, 34755 Istanbul, Turkey
| | - Ebru Toksoy Öner
- Industrial Biotechnology and Systems Biology Research Group-IBSB, Department of Bioengineering, Marmara University, 34722 Istanbul, Turkey.
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3
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Effect of an inorganic nitrogen source (NH 4) 2SO 4 on the production of welan gum from Sphingomonas sp. mutant obtained through UV-ARTP compound mutagenesis. Int J Biol Macromol 2022; 210:630-638. [PMID: 35513098 DOI: 10.1016/j.ijbiomac.2022.04.219] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 04/24/2022] [Accepted: 04/28/2022] [Indexed: 12/14/2022]
Abstract
As one of the most expensive extracellular polysaccharides, welan gum is widely used in biomedicine, food products, and petroleum because of its unique structure and excellent rheological properties. To reduce the cost of welan gum fermentation, together with (NH4)2SO4, which served as the sole nitrogen source, a high-welan-gum-producing mutant, B-8, screened through UV-ARTP compound mutagenesis was used. Under optimum conditions (C:N ratio 25:1, sucrose 50 g/L, (NH4)2SO4 4 g/L, and adding 8 mM NaCl at 32 h fermentation), the yield of welan gum and sucrose conversion were 18.86 g/L and 0.38 g/g, respectively, which were 98.95% and 137.50% higher than those achieved with the parent strain FM01, respectively. After the same treatment process, IN-welan (obtained with (NH4)2SO4) consumed less 95% ethanol, had higher molecular weight, and exhibited better rheological properties than ON-welan (obtained with beef extract). Transcriptome analysis revealed that (NH4)2SO4 could affect the synthetic pathway and monosaccharide content of welan gum by increasing bacterial chemotaxis and the availability of key intermediates. The fermentation performance of Sphingomonas sp. mutants could further be improved by providing several target genes to the mutants through metabolic engineering.
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Mehta K, Shukla A, Saraf M. Articulating the exuberant intricacies of bacterial exopolysaccharides to purge environmental pollutants. Heliyon 2021; 7:e08446. [PMID: 34877428 PMCID: PMC8628041 DOI: 10.1016/j.heliyon.2021.e08446] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 09/23/2021] [Accepted: 11/17/2021] [Indexed: 11/19/2022] Open
Abstract
Microbial exopolysaccharide (EPS) is composed of a mixture of macromolecules such as proteins, polysaccharides, humic-like compounds, and nucleic acids, which encase microbial cells in a three-dimensional matrix. The literature shows that the EPS possess significant properties such as renewable, biodegradable, eco-friendly, non-toxic, and economically valued product, representing it as a green alternative to the synthetic polymer. The cost-effective and green synthesis of the EPS must be encouraged by using agro-waste as a raw material. The main objective of the manuscript is to provide a comprehensive update on the various aspects pertaining to EPS, including the economic aspects of EPS production, provide an insight into the latest tools and techniques used for detailed structural EPS characterization along with updates in the integration of CRISPR/Cas9 technology for engineering the modification in EPS production, the role of newly discovered EPR3 as a signalling molecule in plant growth-promoting properties (PGP) or agricultural microbiology. Furthermore, the EPS achieved prospective interest prevailing potential environmental issues which can be subject to EPS treatment including, landfill leachate treatment, decolourization of dye from the effluent or waste generated by an industry, removal of radionuclides, heavy metals and toxic compounds from the various environments (aquatic and terrestrial), industry effluents, waste waters etc. are comprehensively discussed.
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Affiliation(s)
- Krina Mehta
- Department of Microbiology & Biotechnology, University School of Sciences, Gujarat University, Ahmedabad 380009, Gujarat, India
| | - Arpit Shukla
- Department of Biological Sciences and Biotechnology, Institute of Advanced Research, University of Innovation, Koba Institutional Area, Gandhinagar 382426, Gujarat, India
| | - Meenu Saraf
- Department of Microbiology & Biotechnology, University School of Sciences, Gujarat University, Ahmedabad 380009, Gujarat, India
- Corresponding author.
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5
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Ke C, Wei L, Wang M, Li Q, Liu X, Guo Y, Li S. Effect of NaCl addition on the production of welan gum with the UV mutant of Sphingomonas sp. Carbohydr Polym 2021; 265:118110. [PMID: 33966819 DOI: 10.1016/j.carbpol.2021.118110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 04/07/2021] [Accepted: 04/16/2021] [Indexed: 02/03/2023]
Abstract
Because of its excellent stability, non-toxicity, biodegradability and unique rheology, welan gum can be widely used in various fields, such as petroleum, biomedicine and food products. In this study, a high-yield mutant strain FM01-S09 was screened through two rounds of UV mutagenesis. Remarkably, the production of welan gum could be further increased by adding 4 mM NaCl at 32 h fermentation, reaching 30.12 ± 0.25 g/L (28.66% higher than no adding), and the NaCl-WG solution had stronger structural, impact resistance, and temperature resistance than H2O2-WG and WG solutions. Furthermore, the mechanism by which NaCl promotes welan gum synthesis was also investigated. It was found that cell membrane characteristics, intracellular microenvironment makeup, and key enzyme gene expression levels were significantly altered in different fermentation stages. Therefore, the addition of NaCl could effectively promote the growth and fermentation performance of Sphingomonas sp., providing a novel strategy for cost-effective welan gum production.
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Affiliation(s)
- Chengzhu Ke
- College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China
| | - Lulu Wei
- College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China
| | - Miao Wang
- College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China
| | - Qiwen Li
- College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China
| | - Xiaoling Liu
- 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
| | - Shubo Li
- College of Light Industry and Food Engineering, Guangxi University, Nanning 530004, China.
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6
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Zhao M, Zhang H, Xu X, Li S, Xu H. A strategy for the synthesis of low-molecular-weight welan gum by eliminating capsule form of Sphingomonas strains. Int J Biol Macromol 2021; 178:11-18. [PMID: 33636257 DOI: 10.1016/j.ijbiomac.2021.02.157] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 02/18/2021] [Accepted: 02/20/2021] [Indexed: 10/22/2022]
Abstract
Welan gum is widely used in food, concrete additives, and oil recovery. Here we changed the capsule form of Sphingomonas strains by knocked out the sortase gene (srtW). The obtained welan gum was mainly composed of mannose, glucose, rhamnose, and glucuronic acid at a molar ratio of 4.0:5.8:1.6:1, respectively. Meanwhile, the molecular weight of welan gum decreased sharply (about 68 kDa). Moreover, the low molecular weight (LMW) welan gum was characterized by FT-IR and NMR spectroscopy. The rheological results revealed that the LMW welan gum solution is a pseudoplastic fluid with a lower apparent viscosity. Furthermore, the oscillation test illustrated stable dynamic viscoelasticity within the temperature range of 5-68 °C and frequency range of 0.01-15 rad/s. To the best of our knowledge, this is the first report of LMW welan gum production and characterization. These results provide references for LMW welan gum applications, and likely applicable for other biopolymers production.
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Affiliation(s)
- Ming Zhao
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Hao Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Xiaoqi Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China
| | - Sha Li
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
| | - Hong Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
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7
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Chang AP, Qian J, Li H, Wang YL, Lin JY, He QM, Shen YL, Zhu H. Characterization and Function of a Novel Welan Gum Lyase From Marine Sphingomonas sp. WG. Front Microbiol 2021; 12:638355. [PMID: 33633718 PMCID: PMC7899989 DOI: 10.3389/fmicb.2021.638355] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 01/20/2021] [Indexed: 11/13/2022] Open
Abstract
Welan gum, a kind of microbial exopolysaccharides, produced by the genus Sphingomonas, have great potential for application in many fields, such as the food industry, cement production, and enhanced oil recovery. But there are still challenges to reduce the cost, enhance the production and the quality. Herein, the bioinformatics analysis of WelR gene was preformed, and the characterization and function of WelR, welan gum lyase, from Sphingomonas sp. WG were investigated for the first time. The results indicated that 382nd (Asn), 383rd (Met), 494th (Asn), and 568th (Glu) were the key amino acid residues, and C-terminal amino acids were essential to keeping the stability of WelR. The optimal temperature and pH of the enzymatic activity were found to be 25°C and 7.4, respectively. And WelR was good low temperature resistance and alkali resistant. K+, Mg2+, Ca2+, Mn2+, and EDTA increased WelR activities, in contrast to Zn2+. Coupled with the change in glucose concentration and growth profile, the qRT-PCR results indicated that WelR may degrade welan gum existing in the culture to maintain bacterial metabolism when glucose was depleted. This work will lay a theoretical foundation to establish new strategies for the regulation of welan gum biosynthesis.
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Affiliation(s)
- Ai-Ping Chang
- Engineering Research Center of Industrial Biocatalysis, Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering, Fujian Provincial Key Laboratory of Polymer Materials, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, College of Chemistry and Materials Science, Fujian Normal University, Fuzhou, China
| | - Jin Qian
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Hui Li
- Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, China
| | - Ying-Lu Wang
- Engineering Research Center of Industrial Biocatalysis, Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering, Fujian Provincial Key Laboratory of Polymer Materials, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, College of Chemistry and Materials Science, Fujian Normal University, Fuzhou, China
| | - Jie-Ying Lin
- Engineering Research Center of Industrial Biocatalysis, Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering, Fujian Provincial Key Laboratory of Polymer Materials, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, College of Chemistry and Materials Science, Fujian Normal University, Fuzhou, China
| | - Qiao-Mei He
- Engineering Research Center of Industrial Biocatalysis, Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering, Fujian Provincial Key Laboratory of Polymer Materials, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, College of Chemistry and Materials Science, Fujian Normal University, Fuzhou, China
| | - Ya-Ling Shen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Hu Zhu
- Engineering Research Center of Industrial Biocatalysis, Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering, Fujian Provincial Key Laboratory of Polymer Materials, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, College of Chemistry and Materials Science, Fujian Normal University, Fuzhou, China
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8
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Laubach J, Joseph M, Brenza T, Gadhamshetty V, Sani RK. Exopolysaccharide and biopolymer-derived films as tools for transdermal drug delivery. J Control Release 2021; 329:971-987. [DOI: 10.1016/j.jconrel.2020.10.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 10/13/2020] [Accepted: 10/14/2020] [Indexed: 02/06/2023]
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9
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Xu XY, Sun L, Li S, Xu H, Lei P. Welan gum promoted the growth of rice seedlings by enhancing carbon and nitrogen assimilation. Carbohydr Res 2020; 498:108181. [PMID: 33220604 DOI: 10.1016/j.carres.2020.108181] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 10/09/2020] [Accepted: 10/14/2020] [Indexed: 11/18/2022]
Abstract
Based on the characteristics of natural polysaccharides in film-forming, chelating, and environmental friendly, a natural polysaccharide fertilizer agent was selected to increase the utilization of nitrogen fertilizer and increase plant growth. Five polysaccharides: xanthan gum, guar gum, fenugreek gum, welan gum and chitosan were screened for plant growth promoting effect. The results showed that welan gum had the most significant effect on promoting the growth of rice seedlings, and the concentrations of 0.1 mg mL-1 and 0.15 mg mL-1 showed the best growth effects. The effects of welan gum on nitrogen utilization in rice seedlings were investigated. Results showed welan gum increased the contents of ammonium, nitrate, free amino acids, and proteins in rice seedlings. There were four key enzymes of nitrogen metabolism which are nitrate reductase, glutamine synthetase, glutamate synthase, and glutamate dehydrogenase significantly enhanced by welan gum though up-regulating the transcriptional levels of these enzymes. Therefore, nitrogen uptake and nitrogen metabolism in rice seedlings were promoted to increase the biomass of rice seedlings. Based on the research, results showed that welan gum could constitute a promising fertilizer in the future.
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Affiliation(s)
- Xiao Ying Xu
- College of Food Science and Engineering, Nanjing University of Finance and Economics, No.3 Wenyuan Road, Qixia District, Nanjing, 210023, China
| | - Liang Sun
- College of Food Science and Light Industry, Nanjing Tech University, No. 30 Puzhu South Road, Pukou District, Nanjing, 211800, China
| | - Sha Li
- College of Food Science and Light Industry, Nanjing Tech University, No. 30 Puzhu South Road, Pukou District, Nanjing, 211800, China
| | - Hong Xu
- College of Food Science and Light Industry, Nanjing Tech University, No. 30 Puzhu South Road, Pukou District, Nanjing, 211800, China
| | - Peng Lei
- College of Food Science and Light Industry, Nanjing Tech University, No. 30 Puzhu South Road, Pukou District, Nanjing, 211800, China.
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10
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Lactobacillus exopolysaccharides: New perspectives on engineering strategies, physiochemical functions, and immunomodulatory effects on host health. Trends Food Sci Technol 2020. [DOI: 10.1016/j.tifs.2020.06.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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11
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Li Q, Zhou Y, Ke C, Bai Y, Liu X, Li S. Production of welan gum from cane molasses by Sphingomonas sp. FM01. Carbohydr Polym 2020; 244:116485. [DOI: 10.1016/j.carbpol.2020.116485] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 05/03/2020] [Accepted: 05/19/2020] [Indexed: 01/02/2023]
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12
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Liu X, Zhao M, Xu Z, Xu H, Li S. Construction of a Robust Sphingomonas sp. Strain for Welan Gum Production via the Expression of Global Transcriptional Regulator IrrE. Front Bioeng Biotechnol 2020; 8:674. [PMID: 32695762 PMCID: PMC7338795 DOI: 10.3389/fbioe.2020.00674] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 06/01/2020] [Indexed: 11/16/2022] Open
Abstract
Welan gum is a widely used microbial polysaccharide produced by Sphingomonas sp. However, an important factor hindering the expansion of its production is the maladaptation of strain to fermentation conditions. In this work, the global transcriptional regulator gene irre was selected as a stress-resistant element. And it was integrated into the site of the genomic carotene synthesis key enzyme gene crtB to construct a robust carotenoid-free welan gum producing strain. Fermentation with the recombinant strain effectively reduced the ethanol consumption and pigment content in the product. The tolerance temperature increased by 10°C without the need for controlling the pH. Under this fermentation condition, welan gum concentration could still reach 20.26 ± 0.25 g/L, which was 187.38% higher than that of the wild-type strain (7.05 ± 0.15 g/L). Transcriptome analysis showed that with the control of IrrE, more than 1000 genes that are involved in multiple pathways, including two-component system, bacterial chemotaxis, flagellar assembly, and cell cycle, exhibited changes at the transcriptional level and jointly allowed the strain to protect against environmental stresses.
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Affiliation(s)
- Xiaoliu Liu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, China.,College of Bioscience and Engineering, Hebei University of Economics and Business, Shijiazhuang, China
| | - Ming Zhao
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, China.,College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China
| | - Zheng Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, China.,College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China
| | - Hong Xu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, China.,College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China.,Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing, China
| | - Sha Li
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, China.,College of Food Science and Light Industry, Nanjing Tech University, Nanjing, China
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13
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Transcriptome analysis of polysaccharide-based microbial flocculant MBFA9 biosynthesis regulated by nitrogen source. Sci Rep 2020; 10:2918. [PMID: 32075995 PMCID: PMC7031244 DOI: 10.1038/s41598-020-59114-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 01/21/2020] [Indexed: 11/09/2022] Open
Abstract
Microbial flocculant (MBF), an environmentally friendly water treatment agent, can be widely used in various water treatments. However, its use is limited by low yield and high cost. This problem can be solved by clarifying its biosynthesis mechanism and regulating it. Paenibacillus shenyangensis A9, a flocculant-producing bacterium, was used to produce polysaccharide-type MBFA9 by regulating the nitrogen source (nitrogen adequacy/nitrogen deficiency). In this study, RNA-Seq high-throughput sequencing technology and bioinformatic approaches were used to investigate the fermentation and biosynthesis of polysaccharide-type MBFA9 by regulating the nitrogen source (high nitrogen/low nitrogen) in the flocculant-producing bacteria Paenibacillus shenyangensis A9. Differentially expressed genes, functional clustering, and functional annotation of key genes were assessed. Then the MBFA9 biosynthesis and metabolic pathway were reconstructed. Our results showed that when cultured under different nitrogen conditions, bacterial strain A9 had a greater ability to synthesize polysaccharide-type MBFA9 under low nitrogen compared to high nitrogen conditions, with the yield of MBFA9 reaching 4.2 g/L at 36 h of cultivation. The quality of transcriptome sequencing data was reliable, with a matching rate of 85.38% and 85.48% when L36/H36 was mapped to the reference genome. The total expressed genes detected were 4719 and 4730, with 265 differentially expressed genes. The differentially expressed genes were classified into 3 categories: molecular function (MF), cell component (CC), and biological process (BP), and can be further divided into 22 subcategories. There were 192 upregulated genes and 73 downregulated genes, with upregulation being predominant under low nitrogen. UDP-Gal, UDP-Glc, UDP-GlcA, and UDP-GlcNAc, which are in the polysaccharide metabolic pathway, could all be used as precursors for MBFA9 biosynthesis, and murA, wecB, pgm, galU/galF, fcl, gmd, and glgC were the main functional genes capable of affecting the growth of bacteria and the biosynthesis of MBF. Results from this study provide evidence that high-level expression of key genes in MBFA9 biosynthesis, regulation, and control can achieve MBFA9 directional synthesis for large-scale applications.
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14
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Wang J, Goh KM, Salem DR, Sani RK. Genome analysis of a thermophilic exopolysaccharide-producing bacterium - Geobacillus sp. WSUCF1. Sci Rep 2019; 9:1608. [PMID: 30733471 PMCID: PMC6367360 DOI: 10.1038/s41598-018-36983-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 11/16/2018] [Indexed: 11/23/2022] Open
Abstract
Geobacillus sp. WSUCF1 is a Gram-positive, spore-forming, aerobic and thermophilic bacterium, isolated from a soil sample obtained from a compost facility. Strain WSUCF1 demonstrated EPS producing capability using different sugars as the carbon source. The whole-genome analysis of WSUCF1 was performed to disclose the essential genes correlated with nucleotide sugar precursor biosynthesis, assembly of monosaccharide units, export of the polysaccharide chain, and regulation of EPS production. Both the biosynthesis pathway and export mechanism of EPS were proposed based on functional annotation. Additionally, the genome description of strain WSUCF1 suggests sophisticated systems for its adaptation under thermophilic conditions. The presence of genes associated with CRISPR-Cas system, quorum quenching lactonase, polyketide synthesis and arsenic resistance makes this strain a potential candidate for various applications in biotechnology and biomedicine. The present study indicates that strain WSUCF1 has promise as a thermophilic EPS producer for a broad range of industrial applications. To the best of our knowledge, this is the first report on genome analysis of a thermophilic Geobacillus species focusing on its EPS biosynthesis and transportation, which will likely pave the way for both enhanced yield and tailor-made EPS production by thermophilic bacteria.
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Affiliation(s)
- Jia Wang
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA
- BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA
| | - Kian Mau Goh
- Faculty of Science, Universiti Teknologi Malaysia, Skudai, Johor, 81300, Malaysia
| | - David R Salem
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
- Department of Materials and Metallurgical Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
- Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio Center), Rapid City, SD, 57701, USA.
| | - Rajesh K Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
- Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio Center), Rapid City, SD, 57701, USA.
- BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
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Extremophilic exopolysaccharides: A review and new perspectives on engineering strategies and applications. Carbohydr Polym 2019; 205:8-26. [DOI: 10.1016/j.carbpol.2018.10.011] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 09/20/2018] [Accepted: 10/04/2018] [Indexed: 12/16/2022]
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16
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Two-step economical welan gum production by Sphingomonas sp. HT-1 from sugar industrial by-products. Carbohydr Polym 2017; 181:412-418. [PMID: 29253990 DOI: 10.1016/j.carbpol.2017.09.033] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 08/29/2017] [Accepted: 09/10/2017] [Indexed: 01/18/2023]
Abstract
A two-step fermentation strategy using glucose mother liquor (GML) for cell growth and xylose mother liquor (XML) for welan gum synthesis was used to alleviate uneconomic welan gum fermentation. This study revealed: (1) optimal initial GML concentration was 11.7g/L (10g/L sugars contained); (2) optimal XML feeding strategy was pseudo-exponential fed-batch and feeding time was 12thh-54thh, amounting to 25.7g/L XML (20g/L sugars contained); and (3) in a 7.5-L bioreactor, welan gum concentration was 22.68±0.50g/L and its yield reached 0.756g/g sugars with trace residual sugars. Compared with the cost of batch fermentation using glucose as sole carbon source, the final carbon source costs decreased by 61.40% and the welan gum yield increased by 50%. GML and XML can be used as inexpensive carbon sources for welan gum production with higher yield, giving them industrial application potential to produce value-added chemicals.
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Enhancement of welan gum production in Sphingomonas sp. HT-1 via heterologous expression of Vitreoscilla hemoglobin gene. Carbohydr Polym 2017; 156:135-142. [DOI: 10.1016/j.carbpol.2016.08.081] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 08/24/2016] [Accepted: 08/25/2016] [Indexed: 11/24/2022]
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Zhang W, Chen Z, Wu M, Shi Z, Zhu F, Li G, Ma T. Improved production of carotenoid-free welan gum in a genetic-engineered Alcaligenes sp. ATCC31555. Biotechnol Lett 2016; 38:991-7. [PMID: 26932903 DOI: 10.1007/s10529-016-2068-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 02/25/2016] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To improve the production of welan gum and obtain a carotenoid-free strain while reducing the fermentation and post-treatment costs. RESULTS The vitreoscilla globin (vgb) gene combined with the β-galactosidase (lacZ) promoter was inserted into the phytoene synthase (crtB) gene region of the chromosome in Alcaligenes sp. ATCC31555. When the recombinant strain was grown in a 5 l fermentor, welan gum was produced at 24 ± 0.4 g l(-1) compared to 21 g ± 0.4 g l(-1) in the wild type. Furthermore, the carotenoid-free welan gum produced using Alcaligenes sp. ATCC31555 VHb strain was less expensive with improved properties. CONCLUSIONS Alcaligenes sp. ATCC31555 VHb strain was a better neutral welan-producing strain with a higher production than the wild-type strain.
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Affiliation(s)
- Wenwen Zhang
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Zhaohui Chen
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Mengmeng Wu
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Zhong Shi
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Feng Zhu
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Guoqiang Li
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Ting Ma
- Key Laboratory of Molecular Microbiology Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China.
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Ai H, Liu M, Yu P, Zhang S, Suo Y, Luo P, Li S, Wang J. Improved welan gum production by Alcaligenes sp. ATCC31555 from pretreated cane molasses. Carbohydr Polym 2015; 129:35-43. [DOI: 10.1016/j.carbpol.2015.04.033] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 04/14/2015] [Accepted: 04/15/2015] [Indexed: 11/15/2022]
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21
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Welan gum: Microbial production, characterization, and applications. Int J Biol Macromol 2014; 65:454-61. [DOI: 10.1016/j.ijbiomac.2014.01.061] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 01/28/2014] [Accepted: 01/30/2014] [Indexed: 11/19/2022]
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Improvement of welan gum production and redistribution of metabolic flux under pH control process in Alcaligenes sp. CGMCC2428. BIOTECHNOL BIOPROC E 2013. [DOI: 10.1007/s12257-012-0423-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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23
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A comparative study on physiological activities of lager and ale brewing yeasts under different gravity conditions. BIOTECHNOL BIOPROC E 2012. [DOI: 10.1007/s12257-011-0658-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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24
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Li H, Xu H, Li S, Feng X, Xu H, Ouyang P. Effects of dissolved oxygen and shear stress on the synthesis and molecular weight of welan gum produced from Alcaligenes sp. CGMCC2428. Process Biochem 2011. [DOI: 10.1016/j.procbio.2011.02.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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