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Schwaiger KN, Voit A, Wiltschi B, Nidetzky B. Engineering cascade biocatalysis in whole cells for bottom-up synthesis of cello-oligosaccharides: flux control over three enzymatic steps enables soluble production. Microb Cell Fact 2022; 21:61. [PMID: 35397553 PMCID: PMC8994397 DOI: 10.1186/s12934-022-01781-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 03/24/2022] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Soluble cello-oligosaccharides (COS, β-1,4-D-gluco-oligosaccharides with degree of polymerization DP 2-6) have been receiving increased attention in different industrial sectors, from food and feed to cosmetics. Development of large-scale COS applications requires cost-effective technologies for their production. Cascade biocatalysis by the three enzymes sucrose-, cellobiose- and cellodextrin phosphorylase is promising because it enables bottom-up synthesis of COS from expedient substrates such as sucrose and glucose. A whole-cell-derived catalyst that incorporates the required enzyme activities from suitable co-expression would represent an important step towards making the cascade reaction fit for production. Multi-enzyme co-expression to reach distinct activity ratios is challenging in general, but it requires special emphasis for the synthesis of COS. Only a finely tuned balance between formation and elongation of the oligosaccharide precursor cellobiose results in the desired COS. RESULTS Here, we show the integration of cellodextrin phosphorylase into a cellobiose-producing whole-cell catalyst. We arranged the co-expression cassettes such that their expression levels were upregulated. The most effective strategy involved a custom vector design that placed the coding sequences for cellobiose phosphorylase (CbP), cellodextrin phosphorylase (CdP) and sucrose phosphorylase (ScP) in a tricistron in the given order. The expression of the tricistron was controlled by the strong T7lacO promoter and strong ribosome binding sites (RBS) for each open reading frame. The resulting whole-cell catalyst achieved a recombinant protein yield of 46% of total intracellular protein in an optimal ScP:CbP:CdP activity ratio of 10:2.9:0.6, yielding an overall activity of 315 U/g dry cell mass. We demonstrated that bioconversion catalyzed by a semi-permeabilized whole-cell catalyst achieved an industrial relevant COS product titer of 125 g/L and a space-time yield of 20 g/L/h. With CbP as the cellobiose providing enzyme, flux into higher oligosaccharides (DP ≥ 6) was prevented and no insoluble products were formed after 6 h of conversion. CONCLUSIONS A whole-cell catalyst for COS biosynthesis was developed. The coordinated co-expression of the three biosynthesis enzymes balanced the activities of the individual enzymes such that COS production was maximized. With the flux control set to minimize the share of insolubles in the product, the whole-cell synthesis shows a performance with respect to yield, productivity, product concentration and quality that is promising for industrial production.
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Affiliation(s)
- Katharina N. Schwaiger
- grid.432147.70000 0004 0591 4434ACIB-Austrian Centre of Industrial Biotechnology, Krenngasse 37, 8010 Graz, Austria
| | - Alena Voit
- grid.432147.70000 0004 0591 4434ACIB-Austrian Centre of Industrial Biotechnology, Krenngasse 37, 8010 Graz, Austria
| | - Birgit Wiltschi
- grid.432147.70000 0004 0591 4434ACIB-Austrian Centre of Industrial Biotechnology, Krenngasse 37, 8010 Graz, Austria
| | - Bernd Nidetzky
- grid.432147.70000 0004 0591 4434ACIB-Austrian Centre of Industrial Biotechnology, Krenngasse 37, 8010 Graz, Austria ,grid.410413.30000 0001 2294 748XInstitute of Biotechnology and Biochemical Engineering, NAWI Graz, Graz University of Technology, Petersgasse 12, 8010 Graz, Austria
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Gong Z, Yang G, Che C, Liu J, Si M, He Q. Foaming of rhamnolipids fermentation: impact factors and fermentation strategies. Microb Cell Fact 2021; 20:77. [PMID: 33781264 PMCID: PMC8008553 DOI: 10.1186/s12934-021-01516-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 01/11/2021] [Indexed: 11/25/2022] Open
Abstract
Rhamnolipids have recently attracted considerable attentions because of their excellent biosurfactant performance and potential applications in agriculture, environment, biomedicine, etc., but severe foaming causes the high cost of production, restraining their commercial production and applications. To reduce or eliminate the foaming, numerous explorations have been focused on foaming factors and fermentation strategies, but a systematic summary and discussion are still lacking. Additionally, although these studies have not broken through the bottleneck of foaming, they are conducive to understanding the foaming mechanism and developing more effective rhamnolipids production strategies. Therefore, this review focuses on the effects of fermentation components and control conditions on foaming behavior and fermentation strategies responded to the severe foaming in rhamnolipids fermentation and systematically summarizes 6 impact factors and 9 fermentation strategies. Furthermore, the potentialities of 9 fermentation strategies for large-scale production are discussed and some further strategies are suggested. We hope this review can further facilitate the understanding of foaming factors and fermentation strategies as well as conducive to developing the more effective large-scale production strategies to accelerate the commercial production process of rhamnolipids.![]()
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Affiliation(s)
- Zhijin Gong
- School of Life Sciences, Qufu Normal University, Qufu, Shandong Province, 273165, China
| | - Ge Yang
- School of Life Sciences, Qufu Normal University, Qufu, Shandong Province, 273165, China
| | - Chengchuan Che
- School of Life Sciences, Qufu Normal University, Qufu, Shandong Province, 273165, China
| | - Jinfeng Liu
- School of Life Sciences, Qufu Normal University, Qufu, Shandong Province, 273165, China
| | - Meiru Si
- School of Life Sciences, Qufu Normal University, Qufu, Shandong Province, 273165, China
| | - Qiuhong He
- School of Life Sciences, Qufu Normal University, Qufu, Shandong Province, 273165, China.
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The Effectively Simultaneous Production of Cello-oligosaccharide and Glucose Mono-decanoate from Lignocellulose by Enzymatic Esterification. Appl Biochem Biotechnol 2020; 192:600-615. [PMID: 32500429 DOI: 10.1007/s12010-020-03356-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 05/22/2020] [Indexed: 10/24/2022]
Abstract
Cello-oligosaccharide has drawn an increasing attention as the nutritional ingredients of dietary supplements, whose quality is affected by the concentration of monosaccharide. In the present study, an effective process was developed for the simultaneous production of cello-oligosaccharide and glucose mono-decanoate from lignocellulose by enzymatic esterification. During the process, the excessive glucose in cello-oligosaccharide was converted into glucose mono-decanoate, which is a well-known biodegradable nonionic surfactant. The filter paper was initially used as the model to investigate the feasibility of the process, in which the purity of resultant cello-oligosaccharide was increased from 33.3% to 74.3%, simultaneously producing glucose mono-decanoate with a purity of 92.3%. Further verification of 3 kinds of lignocelluloses (switchgrass, cornstalk, and reed) also indicated a good performance of the process. The present process provided an effective strategy to increase the purity of resultant cello-oligosaccharide with the simultaneous production of high value-added products of sugar monoester. Graphical Abstract Simultaneous production of cello-oligosaccharide and glucose mono-decanoate from lignocellulose.
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Jiang J, Zu Y, Li X, Meng Q, Long X. Recent progress towards industrial rhamnolipids fermentation: Process optimization and foam control. BIORESOURCE TECHNOLOGY 2020; 298:122394. [PMID: 31757615 DOI: 10.1016/j.biortech.2019.122394] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 11/06/2019] [Accepted: 11/07/2019] [Indexed: 05/20/2023]
Abstract
The global market for rhamnolipids production holds great promise, and is in need of an economically viable mass-production scheme. Accordingly, several strategies have been employed to improve the efficiency of rhamnolipid production in the past few decades. Currently, rhamnolipids can be produced by Pseudomonas aeruginosa at a high yield (over 70 g/L) when vegetable oil is used as the carbon source under optimized fed-batch cultivations. However, severe foaming during rhamnolipid fermentation inhibits scaling-up and production efficiency. Stop valve was found to effective break the extremely stable rhamnolipids foams during fermentation, and production efficiency of rhamnolipids was highly improved, while its scale-up mechanism needs further study. In addition, the combination of both chemical and mechanical approaches is likely to be more efficiently resolving the foam problem existed in rhamnolipids fermentation than either chemical or mechanical methods alone.
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Affiliation(s)
- Jingjing Jiang
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, PR China
| | - Yunqiao Zu
- School of Chemical Engineering, University of New South Wales, Sydney, Australia
| | - Xiaoyi Li
- Hangzhou Greenda Electronic Materials Co. Ltd., Hangzhou, PR China
| | - Qin Meng
- School of Chemical and Biological Engineering, Zhejiang University, Hangzhou, PR China
| | - Xuwei Long
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, PR China.
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Sodagari M, Invally K, Ju LK. Maximize rhamnolipid production with low foaming and high yield. Enzyme Microb Technol 2017; 110:79-86. [PMID: 29310859 DOI: 10.1016/j.enzmictec.2017.10.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 09/23/2017] [Accepted: 10/12/2017] [Indexed: 11/30/2022]
Abstract
Rhamnolipids are well-known microbial surfactants with many potential applications. Their production cost, however, remains high due to the severe foaming tendency in aerobic fermentation and the relatively low productivity and yield. In this study, we assessed the boundaries set by these constraints after optimization of basic parameters such as dissolved oxygen concentration (DO), pH and carbon sources. DO 10% and pH 5.5-5.7 were found optimal; cell growth and/or rhamnolipid production were slower at lower DO (5%) or pH (5.0) while foaming became hard to control at higher DO (30%) or pH (6.0 and 6.5). Although the Pseudomonas aeruginosa strain used was selected for its high rhamnolipid production from glycerol as substrate, soybean oil was still found to be a better substrate that increased specific rhamnolipid productivity to 25.8mg/g cells-h from the glycerol-supported maximum of 8.9mg/g cells-h. In addition, the foam volume was approximately halved by using soybean oil instead of glycerol as substrate. Analysis by liquid chromatography coupled with mass spectrometry revealed that rhamnolipid compositions from the two carbon sources were also very different, with primarily (82%) monorhamnolipids from soybean oil and more (64%) dirhamnolipids from glycerol. The optimized fermentation produced 42g/l rhamnolipids at a yield of approximately 47% and a volumetric productivity of 220mg/l-h. These values are among the highest reported.
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Affiliation(s)
- Maysam Sodagari
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906, United States.
| | - Krutika Invally
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906, United States
| | - Lu-Kwang Ju
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906, United States.
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Surface adsorption and spontaneous aggregation of rhamnolipid mixtures in aqueous solutions. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2016.06.056] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Hou J, Zhang S, Qiu Z, Han H, Zhang Q. Stimulatory effect and adsorption behavior of rhamnolipids on lignocelluloses degradation system. BIORESOURCE TECHNOLOGY 2017; 224:465-472. [PMID: 27923607 DOI: 10.1016/j.biortech.2016.11.108] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 11/24/2016] [Accepted: 11/27/2016] [Indexed: 06/06/2023]
Abstract
Di-rhamnolipid and mixed rhamnolipid were added to rice straw degrading system to investigate their mechanism of stimulatory effect. By batch adsorption experiments, it was shown that the equilibrium adsorption time of rhamnolipids on rice straw single system was the shortest (50min). The adsorption capacity of Trichoderma reesei single system was the strongest, whose Qe,exp for di-rhamnolipid and mixed rhamnolipid was 10.57×10-2mg·g-1 and 8.13×10-2mg·g-1, respectively. The adsorption of rhamnolipids on consortia system was not the simple adduct of the two single systems. The adsorption of rhamnolipids on the three different systems might belong to chemisorptions. SEM and FTIR analyses were used to observe the morphology and to analyze the chemical functions in lignocellulosic biomass degradation with rhamnolipid. It was shown that after addition of rhamnolipids, the basic tissue in rice straw was severely destroyed and hydrogen bond was formed between biosurfactant and bacteria in lignocellulose degrading system.
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Affiliation(s)
- Jinju Hou
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 200241 Shanghai, China
| | - Shudong Zhang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 200241 Shanghai, China
| | - Zhen Qiu
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 200241 Shanghai, China
| | - Hui Han
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 200241 Shanghai, China
| | - Qiuzhuo Zhang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 200241 Shanghai, China.
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Chu Q, Li X, Xu Y, Wang Z, Huang J, Yu S, Yong Q. Functional cello-oligosaccharides production from the corncob residues of xylo-oligosaccharides manufacture. Process Biochem 2014. [DOI: 10.1016/j.procbio.2014.05.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Sodagari M, Ju LK. Cells Were a More Important Foaming Factor than Free Rhamnolipids in Fermentation of Pseudomonas aeruginosa E03-40 for High Rhamnolipid Production. J SURFACTANTS DETERG 2013. [DOI: 10.1007/s11743-013-1535-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Fang Y, Xu W, Meng XL, Ye XY, Wu J, Xu ZK. Poly(2-hydroxyethyl methacrylate) brush surface for specific and oriented adsorption of glycosidases. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:13318-13324. [PMID: 22921196 DOI: 10.1021/la302738s] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We present a detailed picture to screen general ligands from simple chemicals for fabricating affinity surface to glycosidase enzymes. The surface was constructed by grafting poly(2-hydroxyethyl methacrylate) (PHEMA) brush on SPR gold chip via surface-initiated atom-transfer radical polymerization, after which poly(methoxyethyl methacrylate) (PMEMA) and poly(oligo(ethylene glycol) methacrylate) (POEGMA) brushes were also prepared for comparison. SPR measurements were adopted to monitor the early-stage adsorption of two glycosidases and three other typical proteins. PHEMA resists the adsorption of lysozyme, bovine serum albumin, and fibrinogen, while it is capable of specifically adsorbing β-glucosidase (GLU) and β-galactosidase (GAL). These are quite different from the nonspecific adsorption of PMEMA and the anti-nonspecific adsorption of POEGMA to the studied proteins, because PHEMA is the acceptor substrate of the glycosidases. About 69.6 and 93.7 ng/cm(2) of GAL and GLU are adsorbed on the PHEMA brush surface, of which more than 49.6 ng/cm(2) is remained after washing with PBS. The specific adsorption process is appropriately described by Freundlich isothermal model rather than Langmuir one, and is also indicated to be spontaneous, endothermic, and entropy driven through thermodynamic studies. Taking into account all stated results above, we propose that molecular recognition takes place between the hydroxyl groups of PHEMA and the active sites of glycosidases, which subsequently enables the oriented adsorption of glycosidases on the brush surface. The adsorbed enzyme can be effectively eluted with 1.0 M aqueous solution of ethanol. Our findings open the door to the further development in the design of novel acceptor substrate-ligand affinity chromatography for enzyme purification.
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Affiliation(s)
- Yan Fang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
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