1
|
Fan Y, Wei Z, Zhang Y, Duan X. Enhancing L-asparagine Production Through In Vivo ATP Regeneration System Utilizing Glucose Metabolism of Escherichia coli. Appl Biochem Biotechnol 2024:10.1007/s12010-024-04982-8. [PMID: 38900400 DOI: 10.1007/s12010-024-04982-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/05/2024] [Indexed: 06/21/2024]
Abstract
L-asparaginase synthetase, an ATP-dependent enzyme, necessitates ATP for its catalytic activity. However, the integration of L-asparaginase synthetase into industrial processes is curtailed by the prohibitive cost of ATP. To address this limitation, this study explores the construction of an efficient ATP regeneration system using the glucose metabolism of Escherichia coli, synergistically coupled with L-asparaginase synthetase catalysis. The optimal conditions for L-asparagine yield were determined in shake flasks. A total of 2.7 g/L was the highest yield achieved under specific parameters, including 0.1 mol/L of substrate, 0.2 mol/L glucose, 0.01 mol/L MgCl2 at pH 7.5, a temperature of 37 °C, and agitation at 300 r/min over 12 h. The process was then scaled to a 3-L fermenter, optimizing the addition rates of the substrate and magnesium chloride, and employing a constant glucose feed of 10 g/L/h. The scale-up process led to a significant enhancement in the production of L-asparagine. The yield of L-asparagine was increased to 38.49 g/L after 20 h of conversion, and the molar conversion rate reached 29.16%. This strategy has proven to be effective in improving the efficiency of L-asparagine production. When compared to in vitro ATP regeneration methods, this in vivo approach showcased superior efficiency and reduced costs. These findings furnish pivotal insights that may propel the enzymatic synthesis of L-asparagine toward viable industrial application.
Collapse
Affiliation(s)
- Yucheng Fan
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Zijia Wei
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Yuhua Zhang
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Xuguo Duan
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China.
| |
Collapse
|
2
|
Wei Z, Zhang Y, Duan X, Fan Y. Enhancing L-Asparagine Bioproduction Efficiency Through L-Asparagine Synthetase and Polyphosphate Kinase-Coupled Conversion and ATP Regeneration. Appl Biochem Biotechnol 2024:10.1007/s12010-024-04856-z. [PMID: 38358456 DOI: 10.1007/s12010-024-04856-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/04/2024] [Indexed: 02/16/2024]
Abstract
L-Asparagine, a crucial amino acid widely used in both food and medicine, presents pollution-related and side reaction challenges when prepared using chemical synthesis method. Although biotransformation methods offer significant advantages such as high efficiency and mild reaction conditions, they also entail increased costs due to the need for ATP supplementation. This study aimed to address the challenges associated with biopreparation of L-asparagine. Firstly, the functionality and characteristics of recombinant L-asparagine synthetase enzymes derived from Escherichia coli and Lactobacillus salivarius were evaluated to determine their practical applicability. Subsequently, recombinant expression of polyphosphate kinase from Erysipelotrichaceae bacterium was conducted. A reaction system for L-asparagine synthesis was established using a dual enzyme-coupled conversion approach. Under the optimal reaction conditions, a maximum yield of 11.67 g/L of L-asparagine was achieved, with an 88.43% conversion rate, representing a 5.03-fold increase compared to the initial conversion conditions. Notably, the initial addition of ATP was reduced to only 5.66% of the theoretical demand, indicating the effectiveness of our ATP regeneration system. These findings highlight the potential of our approach in enhancing the efficiency of L-asparagine preparation, offering promising prospects for the food and medical industries.
Collapse
Affiliation(s)
- Zijia Wei
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Yuhua Zhang
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Xuguo Duan
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China.
| | - Yucheng Fan
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| |
Collapse
|
3
|
Taylor JE, Palur DSK, Zhang A, Gonzales JN, Arredondo A, Coulther TA, Lechner ABJ, Rodriguez EP, Fiehn O, Didzbalis J, Siegel JB, Atsumi S. Awakening the natural capability of psicose production in Escherichia coli. NPJ Sci Food 2023; 7:54. [PMID: 37838768 PMCID: PMC10576766 DOI: 10.1038/s41538-023-00231-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 10/02/2023] [Indexed: 10/16/2023] Open
Abstract
Due to the rampant rise in obesity and diabetes, consumers are desperately seeking for ways to reduce their sugar intake, but to date there are no options that are both accessible and without sacrifice of palatability. One of the most promising new ingredients in the food system as a non-nutritive sugar substitute with near perfect palatability is D-psicose. D-psicose is currently produced using an in vitro enzymatic isomerization of D-fructose, resulting in low yield and purity, and therefore requiring substantial downstream processing to obtain a high purity product. This has made adoption of D-psicose into products limited and results in significantly higher per unit costs, reducing accessibility to those most in need. Here, we found that Escherichia coli natively possesses a thermodynamically favorable pathway to produce D-psicose from D-glucose through a series of phosphorylation-epimerization-dephosphorylation steps. To increase carbon flux towards D-psicose production, we introduced a series of genetic modifications to pathway enzymes, central carbon metabolism, and competing metabolic pathways. In an attempt to maximize both cellular viability and D-psicose production, we implemented methods for the dynamic regulation of key genes including clustered regularly interspaced short palindromic repeats inhibition (CRISPRi) and stationary-phase promoters. The engineered strains achieved complete consumption of D-glucose and production of D-psicose, at a titer of 15.3 g L-1, productivity of 2 g L-1 h-1, and yield of 62% under test tube conditions. These results demonstrate the viability of whole-cell catalysis as a sustainable alternative to in vitro enzymatic synthesis for the accessible production of D-psicose.
Collapse
Affiliation(s)
- Jayce E Taylor
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA
| | | | - Angela Zhang
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA
| | - Jake N Gonzales
- Plant Biology Graduate Group, University of California, Davis, Davis, CA, 95616, USA
| | - Augustine Arredondo
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA
| | | | | | - Elys P Rodriguez
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA
- West Coast Metabolomics Center, UC Davis Genome Center, University of California, Davis, Davis, CA, 95616, USA
| | - Oliver Fiehn
- West Coast Metabolomics Center, UC Davis Genome Center, University of California, Davis, Davis, CA, 95616, USA
| | - John Didzbalis
- Mars, Incorporated, 6885 Elm Street, McLean, VA, 22101, USA
| | - Justin B Siegel
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA
- Genome Center, University of California, Davis, Davis, CA, 95616, USA
- Department of Biochemistry and Molecular Medicine, University of California, Davis, Sacramento, CA, 95616, USA
| | - Shota Atsumi
- Department of Chemistry, University of California, Davis, Davis, CA, 95616, USA.
- Plant Biology Graduate Group, University of California, Davis, Davis, CA, 95616, USA.
| |
Collapse
|
4
|
Gao Y, Chen Z, Nakanishi H, Li Z. Highly Efficient Synthesis of Rare Sugars from Glycerol in Endotoxin-Free ClearColi by Fermentation. Foods 2023; 12:3078. [PMID: 37628077 PMCID: PMC10453619 DOI: 10.3390/foods12163078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 08/13/2023] [Accepted: 08/15/2023] [Indexed: 08/27/2023] Open
Abstract
Rare sugars possess potential applications as low-calorie sweeteners, especially for anti-obesity and anti-diabetes. In this study, a fermentation biosystem based on the "DHAP-dependent aldolases strategy" was established for D-allulose and D-sorbose production from glycerol in endotoxin-free ClearColi BL21 (DE3). Several engineering strategies were adopted to enhance rare sugar production. Firstly, the combination of different plasmids for aldO, rhaD, and yqaB expression was optimized. Then, the artificially constructed ribosomal binding site (RBS) libraries of aldO, rhaD, and yqaB genes were assembled individually and combinatorially. In addition, a peroxidase was overexpressed to eliminate the damage or toxicity from hydrogen peroxide generated by alditol oxidase (AldO). Finally, stepwise improvements in rare sugar synthesis were elevated to 15.01 g/L with a high yield of 0.75 g/g glycerol in a 3 L fermenter. This research enables the effective production of rare sugars from raw glycerol in high yields.
Collapse
Affiliation(s)
- Yahui Gao
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Zhou Chen
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Hideki Nakanishi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Zijie Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| |
Collapse
|
5
|
Gao H, Li M, Wang Q, Liu T, Zhang X, Yang T, Xu M, Rao Z. A high-throughput dual system to screen polyphosphate kinase mutants for efficient ATP regeneration in L-theanine biocatalysis. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:122. [PMID: 37537682 PMCID: PMC10401862 DOI: 10.1186/s13068-023-02361-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 06/22/2023] [Indexed: 08/05/2023]
Abstract
ATP, an important cofactor, is involved in many biocatalytic reactions that require energy. Polyphosphate kinases (PPK) can provide energy for ATP-consuming reactions due to their cheap and readily available substrate polyphosphate. We determined the catalytic properties of PPK from different sources and found that PPK from Cytophaga hutchinsonii (ChPPK) had the best catalytic activity for the substrates ADP and polyP6. An extracellular-intracellular dual system was constructed to high-throughput screen for better catalytic activity of ChPPK mutants. Finally, the specific activity of ChPPKD82N-K103E mutant was increased by 4.3 times. Therefore, we focused on the production of L-theanine catalyzed by GMAS as a model of ATP regeneration. Supplying 150 mM ATP, GMAS enzyme could produce 16.8 ± 1.3 g/L L-theanine from 100 mM glutamate. When 5 mM ATP and 5 U/mL ChPPKD82N-K103E were added, the yield of L-theanine was 16.6 ± 0.79 g/L with the conversion rate of 95.6 ± 4.5% at 4 h. Subsequently, this system was scaled up to 200 mM and 400 mM glutamate, resulting in the yields of L-theanine for 32.3 ± 1.6 g/L and 62.7 ± 1.1 g/L, with the conversion rate of 92.8 ± 4.6% and 90.1 ± 1.6%, respectively. In addition, we also constructed an efficient ATP regeneration system from glutamate to glutamine, and 13.8 ± 0.2 g/L glutamine was obtained with the conversion rate of 94.4 ± 1.4% in 4 h after adding 6 U/ mL GS enzyme and 5 U/ mL ChPPKD82N-K103E, which further laid the foundation from glutamine to L-theanine catalyzed by GGT enzyme. This proved that giving the reaction an efficient ATP supply driven by the mutant enzyme enhanced the conversion rate of substrate to product and maximized the substrate value. This is a positively combination of high yield, high conversion rate and high economic value of enzyme catalysis. The mutant enzyme will further power the ATP-consuming biocatalytic reaction platform sustainably.
Collapse
Affiliation(s)
- Hui Gao
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Mengxuan Li
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Qing Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Tingting Liu
- Yantai Shinho Enterprise Foods Co., Ltd., Yantai, 265503, China
| | - Xian Zhang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Taowei Yang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Meijuan Xu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China.
| | - Zhiming Rao
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| |
Collapse
|
6
|
Guo Y, Zhu Z, Lv J, Li Y, Chen J, Cheng X, Li N, Liu J. Irreversible biosynthesis of D-allulose from D-glucose in Escherichia coli through fine-tuning of carbon flux and cofactor regeneration engineering. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2023. [PMID: 37050847 DOI: 10.1002/jsfa.12623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 04/07/2023] [Accepted: 04/13/2023] [Indexed: 06/19/2023]
Abstract
BACKGROUND As a rare hexose with low calories and various physiological functions, d-allulose has drawn increasing attention. The current industrial production of d-allulose from d-fructose or d-glucose is achieved via epimerization based on the Izumoring strategy; however, the inherent reaction equilibrium during reversible reaction limits its high conversion yield. Although the conversion of d-fructose to d-allulose could be enhanced via phosphorylation-dephosphorylation mediated by metabolic engineering, biomass reduction and byproduct accumulation remain a largely unresolved issue. RESULTS After modifying the glycolytic pathway of Escherichia coli and optimizing the whole-cell reaction condition, the engineered strain produced 7.57 ± 0.61 g L-1 d-allulose from 30 g L-1 d-glucose after 24 h of catalysis. By developing an ATP regeneration system for enhanced substrate phosphorylation, the cell growth inhibition was alleviated and d-allulose production increased by 55.3% to 11.76 ± 0.58 g L-1 (0.53 g g-1 ). Fine-tuning of carbon flux caused a 48% reduction in d-fructose accumulation to 1.47 ± 0.15 g L-1 . After implementing fed-batch co-substrate strategy, the d-allulose titer reached 15.80 ± 0.31 g L-1 (0.62 g g-1 ) with a d-glucose conversion rate of 84.8%. CONCLUSION The present study reports a novel strategy for high-yield d-allulose production from low-cost substrate. © 2023 Society of Chemical Industry.
Collapse
Affiliation(s)
- Yan Guo
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| | - Zhengwen Zhu
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| | - Jing Lv
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| | - Yumei Li
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| | - Jing Chen
- Guangxi South Subtropical Agricultural Sciences Research Institute, Longzhou, China
| | - Xiyao Cheng
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| | - Ning Li
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| | - Jidong Liu
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| |
Collapse
|
7
|
Liu C, Song Y, Hu T, Wang S, Yi K, Wang J, Yan Q, Wei L, Zhang Z, Li H, Luo Y, Wu L, Zhang D, Meng E. Adenylate Kinase Fused to Spidroin as a Catalyst for Decreasing Leakage out of 3D-Bioprinted Hydrogels and for ATP Regeneration. Biomacromolecules 2023; 24:1662-1674. [PMID: 36913719 DOI: 10.1021/acs.biomac.2c01445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
Abstract
Numerous metabolic reactions and pathways use adenosine 5'-triphosphate (ATP) as an energy source and as a phosphorous or pyrophosphorous donor. Based on three-dimensional (3D)-printing, enzyme immobilization can be used to improve ATP regeneration and operability and reduce cost. However, due to the relatively large mesh size of 3D-bioprinted hydrogels soaked in a reaction solution, the lower-molecular-weight enzymes cannot avoid leaking out of the hydrogels readily. Here, a chimeric adenylate-kinase-spidroin (ADK-RC) is created, with ADK serving as the N-terminal domain. The chimera is capable of self-assembling to form micellar nanoparticles at a higher molecular scale. Although fused to spidroin (RC), ADK-RC remains relatively consistent and exhibits high activity, thermostability, pH stability, and organic solvent tolerance. Considering different surface-to-volume ratios, three shapes of enzyme hydrogels are designed, 3D bioprinted, and measured. In addition, a continuous enzymatic reaction demonstrates that ADK-RC hydrogels have higher specific activity and substrate affinity but a lower reaction rate and catalytic power compared to free enzymes in solution. With ATP regeneration, the ADK and ADK-RC hydrogels significantly increase the production of d-glucose-6-phosphate and obtain an efficient usage frequency. In conclusion, enzymes fused to spidroin might be an efficient strategy for maintaining activity and reducing leakage in 3D-bioprinted hydrogels under mild conditions.
Collapse
Affiliation(s)
- Changjun Liu
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| | - Yanmin Song
- Department of Emergency Medicine, Xiangya Hospital, Central South University, Changsha 410008, Hunan, P. R. China
| | - Tianhao Hu
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| | - Shan Wang
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| | - Ke Yi
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| | - Jianjie Wang
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| | - Qing Yan
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| | - Li'an Wei
- Changsha Sanjiang Smart Technology Co., Ltd., Changsha 410026, Hunan, P. R. China
| | - Zheyang Zhang
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| | - Huimin Li
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| | - Yutao Luo
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| | - Lei Wu
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| | - Dongyi Zhang
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| | - Er Meng
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China.,Key Laboratory of Genetic Improvement and Multiple Utilization of Economic Crops in Hunan Province, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China.,Key Laboratory of Ecological Remediation and Safe Utilization of Heavy Metal-Polluted Soils, Hunan University of Science and Technology, Xiangtan 411201, Hunan, P. R. China
| |
Collapse
|
8
|
Guo Y, Feng T, Wang Z, Li H, Wei X, Chen J, Niu D, Liu J. Phosphorylation-Driven Production of d-Allulose from d-Glucose by Coupling with an ATP Regeneration System. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:15539-15547. [PMID: 36458726 DOI: 10.1021/acs.jafc.2c06920] [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: 06/17/2023]
Abstract
d-Allulose is a desirable sucrose substitute with potential applications in food and health care. d-Allulose can be synthesized using d-glucose as a substrate through coupling glucose isomerase with d-allulose 3-epimerase (DAEase); however, the product yield is typically less than 20% at reaction equilibrium and thus limits its use in industrial applications. Here, a 3R-ketose phosphorylation pathway coupled with an adenosine triphosphate (ATP) regeneration system was developed for the efficient synthesis of d-allulose in Escherichia coli using d-glucose as a substrate. The l-rhamnulose kinase (RhaB) was used to break the inherent reaction equilibrium due to its substrate specificity, resulting in increases in d-allulose titer by 69.9% to 4.96 ± 0.49 g/L. By optimizing the whole cell transformation conditions and designing an ATP regeneration module, d-allulose production reached 17.62 ± 0.77 g/L from 30 g/L d-glucose with a final yield of 0.73 g/g without the addition of exogenous ATP. To evaluate the potential industrial application of this multienzyme cascade system, d-allulose was produced from cane molasses (124.16 ± 2.69 g/L glucose equivalent) with a final d-allulose titer of 62.60 ± 3.76 g/L. The present study provides a practical enzymatic approach for the economical synthesis of d-allulose.
Collapse
Affiliation(s)
- Yan Guo
- College of Light Industry and Food Engineering, Guangxi University, 100 Daxue Road, Nanning 530004, Guangxi, China
| | - Tingting Feng
- College of Light Industry and Food Engineering, Guangxi University, 100 Daxue Road, Nanning 530004, Guangxi, China
| | - Zhiqi Wang
- College of Light Industry and Food Engineering, Guangxi University, 100 Daxue Road, Nanning 530004, Guangxi, China
| | - Hongwei Li
- College of Light Industry and Food Engineering, Guangxi University, 100 Daxue Road, Nanning 530004, Guangxi, China
| | - Xin Wei
- College of Light Industry and Food Engineering, Guangxi University, 100 Daxue Road, Nanning 530004, Guangxi, China
| | - Jing Chen
- Guangxi South Subtropical Agricultural Sciences Research Institute, Longzhou, Guangxi 532415, China
| | - Debao Niu
- College of Light Industry and Food Engineering, Guangxi University, 100 Daxue Road, Nanning 530004, Guangxi, China
| | - Jidong Liu
- College of Light Industry and Food Engineering, Guangxi University, 100 Daxue Road, Nanning 530004, Guangxi, China
| |
Collapse
|
9
|
Guo Q, Liu CY, Zheng LJ, Zheng SH, Zhang YX, Zhao SY, Zheng HD, Fan LH, Lin XC. Metabolically Engineered Escherichia coli for Conversion of D-Fructose to D-Allulose via Phosphorylation-Dephosphorylation. Front Bioeng Biotechnol 2022; 10:947469. [PMID: 35814008 PMCID: PMC9257026 DOI: 10.3389/fbioe.2022.947469] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 06/07/2022] [Indexed: 11/23/2022] Open
Abstract
D-Allulose is an ultra-low calorie sweetener with broad market prospects. As an alternative to Izumoring, phosphorylation-dephosphorylation is a promising method for D-allulose synthesis due to its high conversion of substrate, which has been preliminarily attempted in enzymatic systems. However, in vitro phosphorylation-dephosphorylation requires polyphosphate as a phosphate donor and cannot completely deplete the substrate, which may limit its application in industry. Here, we designed and constructed a metabolic pathway in Escherichia coli for producing D-allulose from D-fructose via in vivo phosphorylation-dephosphorylation. PtsG-F and Mak were used to replace the fructose phosphotransferase systems (PTS) for uptake and phosphorylation of D-fructose to fructose-6-phosphate, which was then converted to D-allulose by AlsE and A6PP. The D-allulose titer reached 0.35 g/L and the yield was 0.16 g/g. Further block of the carbon flux into the Embden-Meyerhof-Parnas (EMP) pathway and introduction of an ATP regeneration system obviously improved fermentation performance, increasing the titer and yield of D-allulose to 1.23 g/L and 0.68 g/g, respectively. The E. coli cell factory cultured in M9 medium with glycerol as a carbon source achieved a D-allulose titer of ≈1.59 g/L and a yield of ≈0.72 g/g on D-fructose.
Collapse
Affiliation(s)
- Qiang Guo
- Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine Chemicals, College of Chemical Engineering, Fuzhou University, Fuzhou, China
| | - Chen-Yang Liu
- Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine Chemicals, College of Chemical Engineering, Fuzhou University, Fuzhou, China
| | - Ling-Jie Zheng
- Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine Chemicals, College of Chemical Engineering, Fuzhou University, Fuzhou, China
| | - Shang-He Zheng
- Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine Chemicals, College of Chemical Engineering, Fuzhou University, Fuzhou, China
| | - Ya-Xing Zhang
- Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine Chemicals, College of Chemical Engineering, Fuzhou University, Fuzhou, China
| | - Su-Ying Zhao
- Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine Chemicals, College of Chemical Engineering, Fuzhou University, Fuzhou, China
- Qingyuan Innovation Laboratory, Quanzhou, China
| | - Hui-Dong Zheng
- Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine Chemicals, College of Chemical Engineering, Fuzhou University, Fuzhou, China
- Qingyuan Innovation Laboratory, Quanzhou, China
| | - Li-Hai Fan
- Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine Chemicals, College of Chemical Engineering, Fuzhou University, Fuzhou, China
- Qingyuan Innovation Laboratory, Quanzhou, China
- *Correspondence: Li-Hai Fan, ; Xiao-Cheng Lin,
| | - Xiao-Cheng Lin
- Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine Chemicals, College of Chemical Engineering, Fuzhou University, Fuzhou, China
- *Correspondence: Li-Hai Fan, ; Xiao-Cheng Lin,
| |
Collapse
|
10
|
Zhang W, Chen D, Chen J, Xu W, Chen Q, Wu H, Guang C, Mu W. D-allulose, a versatile rare sugar: recent biotechnological advances and challenges. Crit Rev Food Sci Nutr 2021; 63:5661-5679. [PMID: 34965808 DOI: 10.1080/10408398.2021.2023091] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
D-Allulose is the C-3 epimer of D-fructose, and widely regarded as a promising substitute for sucrose. It's an excellent low-calorie sweetener, with 70% sweetness of sucrose, 0.4 kcal/g dietary energy, and special physiological functions. It has been approved as GRAS by the U.S. Food and Drug Administration, and is allowed to be excluded from total and added sugar counts on the food labels. Therefore, D-allulose gradually attracts more public attention. Owing to scarcity in nature, the bioproduction of D-allulose by using ketose 3-epimerase (KEase) has become the research hotspot. Herein, we give a summary of the physicochemical properties, physiological function, applications, and the chemical and biochemical synthesis methods of D-allulose. In addition, the recent progress in the D-allulose bioproduction using KEases, and the possible solutions for existing challenges in the D-allulose industrial production are comprehensively discussed, focusing on the molecular modification, immobilization, food-grade expression, utilizing low-cost biomass as feedstock, overcoming thermodynamic limitation, as well as the downstream separation and purification. Finally, Prospects for further development are also proposed.
Collapse
Affiliation(s)
- Wenli Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Ding Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Jiajun Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Wei Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Qiuming Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Hao Wu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Cuie Guang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
- Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi, China
| |
Collapse
|
11
|
Li Z, Tan H, Lu N, Zhang Z, Chang J. Enhanced ATP and antioxidant levels for cAMP biosynthesis by Arthrobacter sp. CCTCC 2013431 with polyphosphate addition. Biotechnol Lett 2021; 43:2223-2231. [PMID: 34676500 DOI: 10.1007/s10529-021-03197-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 10/13/2021] [Indexed: 01/10/2023]
Abstract
OBJECTIVES When citrate and pyruvate were utilized to strengthen ATP generation for high cAMP production, oxidative stress became more severe in cells resulting in lower cell viability and cAMP formation at the late fermentation phase. To further improve cAMP biosynthesis, the effects of polyphosphate on cAMP fermentation performance together with intracellular ATP and oxidation levels were investigated under high oxidative stress condition and then high efficient cAMP fermentation process based on polyphosphate and salvage synthesis was developed and studied. RESULTS With 2 g/L-broth sodium hexametaphosphate added at 24 h was determined as the optimal condition for cAMP production by Arthrobacter sp. CCTCC 2013431 in shake flasks. Under high oxidative stress condition caused by adding 15 mg/L-broth menadione, cAMP contents and cell viability were improved greatly due to hexametaphosphate addition and also exceeded those of control (without hexametaphosphate and menadione added) when fermentations were conducted in a 7 L bioreactor. Meanwhile, ATP levels and antioxidant capacity were improved obviously by hexametaphosphate as well. Moreover, a fermentation process with hexametaphosphate and hypoxanthine coupling added was developed by which cAMP concentration reached 7.25 g/L with an increment of 87.1% when compared with only hypoxanthine added batch and the high ROS contents generated from salvage synthesis were reduced significantly. CONCLUSION Polyphosphate could improve intracellular ATP levels and antioxidant capacity significantly under high oxidative stress condition resulting in enhanced cell viability and cAMP fermentation production no matter by de novo synthesis or salvage synthesis.
Collapse
Affiliation(s)
- Zhigang Li
- Collaborative Innovation Center of Modem Biological Breeding of Henan Province, Xinxiang, 453003, China.,School of Life Science and Technology, Henan Institute of Science and Technology, 90 Hualan Road, Xinxiang, 453003, Henan Province, China
| | - Hai Tan
- School of Life Science and Technology, Henan Institute of Science and Technology, 90 Hualan Road, Xinxiang, 453003, Henan Province, China
| | - Nanxun Lu
- School of Life Science and Technology, Henan Institute of Science and Technology, 90 Hualan Road, Xinxiang, 453003, Henan Province, China
| | - Zhonghua Zhang
- School of Life Science and Technology, Henan Institute of Science and Technology, 90 Hualan Road, Xinxiang, 453003, Henan Province, China
| | - Jingling Chang
- School of Life Science and Technology, Henan Institute of Science and Technology, 90 Hualan Road, Xinxiang, 453003, Henan Province, China.
| |
Collapse
|
12
|
Hu M, Li M, Jiang B, Zhang T. Bioproduction of D-allulose: Properties, applications, purification, and future perspectives. Compr Rev Food Sci Food Saf 2021; 20:6012-6026. [PMID: 34668314 DOI: 10.1111/1541-4337.12859] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 09/07/2021] [Accepted: 09/17/2021] [Indexed: 11/29/2022]
Abstract
D-allulose is the C-3 epimer of D-fructose, which rarely exists in nature, and can be biosynthesized from D-fructose by the catalysis of D-psicose 3-epimerase. D-allulose is safe for human consumption and was recently approved by the United States Food and Drug Administration for food applications. It is not only able be used in food and dietary supplements as a low-calorie sweetener, but also modulates a variety of physiological functions. D-allulose has gained increasing attention owing to its excellent properties. This article presents a review of recent progress on the properties, applications, and bioproduction progress of D-allulose.
Collapse
Affiliation(s)
- Mengying Hu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Mengli Li
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Bo Jiang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Tao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, Jiangsu, 214122, China
| |
Collapse
|
13
|
Luo W, Xu J, Chen H, Zhang H, Yang P, Yu X. Synthesis of L-asparagine Catalyzed by a Novel Asparagine Synthase Coupled With an ATP Regeneration System. Front Bioeng Biotechnol 2021; 9:747404. [PMID: 34631686 PMCID: PMC8495130 DOI: 10.3389/fbioe.2021.747404] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 08/09/2021] [Indexed: 11/23/2022] Open
Abstract
Compared with low-yield extraction from plants and environmentally unfriendly chemical synthesis, biocatalysis by asparagine synthetase (AS) for preparation of L-asparagine (L-Asn) has become a potential synthetic method. However, low enzyme activity of AS and high cost of ATP in this reaction restricts the large-scale preparation of L-Asn by biocatalysis. In this study, gene mining strategy was used to search for novel AS with high enzyme activity by expressing them in Escherichia coli BL21 (DE3) or Bacillus subtilis WB600. The obtained LsaAS-A was determined for its enzymatic properties and used for subsequent preparation of L-Asn. In order to reduce the use of ATP, a class III polyphosphate kinase 2 from Deinococcus ficus (DfiPPK2-Ⅲ) was cloned and expressed in E. coli BL21 (DE3), Rosetta (DE3) or RosettagamiB (DE3) for ATP regeneration. A coupling reaction system including whole cells expressing LsaAS-A and DfiPPK2-Ⅲ was constructed to prepare L-Asn from L-aspartic acid (L-Asp). Batch catalytic experiments showed that sodium hexametaphosphate (>60 mmol L−1) and L-Asp (>100 mmol L−1) could inhibit the synthesis of L-Asn. Under fed-batch mode, L-Asn yield reached 90.15% with twice feeding of sodium hexametaphosphate. A final concentration of 218.26 mmol L−1 L-Asn with a yield of 64.19% was obtained when L-Asp and sodium hexametaphosphate were fed simultaneously.
Collapse
Affiliation(s)
- Wei Luo
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Jinglong Xu
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Huiying Chen
- College of Chemistry and Bioengineering, Guilin University of Technology, Guilin, China
| | - Huili Zhang
- College of Life Sciences, University of Shihezi, Shihezi, China
| | - Peilong Yang
- Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Institute of Feed Research of CAAS, Beijing, China
| | - Xiaobin Yu
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| |
Collapse
|
14
|
Tong T, Chen X, Hu G, Wang XL, Liu GQ, Liu L. Engineering microbial metabolic energy homeostasis for improved bioproduction. Biotechnol Adv 2021; 53:107841. [PMID: 34610353 DOI: 10.1016/j.biotechadv.2021.107841] [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: 06/16/2021] [Revised: 08/25/2021] [Accepted: 09/28/2021] [Indexed: 10/20/2022]
Abstract
Metabolic energy (ME) homeostasis is essential for the survival and proper functioning of microbial cell factories. However, it is often disrupted during bioproduction because of inefficient ME supply and excessive ME consumption. In this review, we propose strategies, including reinforcement of the capacity of ME-harvesting systems in autotrophic microorganisms; enhancement of the efficiency of ME-supplying pathways in heterotrophic microorganisms; and reduction of unessential ME consumption by microbial cells, to address these issues. This review highlights the potential of biotechnology in the engineering of microbial ME homeostasis and provides guidance for the higher efficient bioproduction of microbial cell factories.
Collapse
Affiliation(s)
- Tian Tong
- Hunan Provincial Key Laboratory for Forestry Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China; International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry and Technology, Changsha 410004, China
| | - Xiulai Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China
| | - Guipeng Hu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China
| | - Xiao-Ling Wang
- Hunan Provincial Key Laboratory for Forestry Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China; International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry and Technology, Changsha 410004, China
| | - Gao-Qiang Liu
- Hunan Provincial Key Laboratory for Forestry Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China; International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry and Technology, Changsha 410004, China.
| | - Liming Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China.
| |
Collapse
|
15
|
Xia Y, Cheng Q, Mu W, Hu X, Sun Z, Qiu Y, Liu X, Wang Z. Research Advances of d-allulose: An Overview of Physiological Functions, Enzymatic Biotransformation Technologies, and Production Processes. Foods 2021; 10:2186. [PMID: 34574296 PMCID: PMC8467252 DOI: 10.3390/foods10092186] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 09/08/2021] [Accepted: 09/12/2021] [Indexed: 02/02/2023] Open
Abstract
d-allulose has a significant application value as a sugar substitute, not only as a food ingredient and dietary supplement, but also with various physiological functions, such as improving insulin resistance, anti-obesity, and regulating glucolipid metabolism. Over the decades, the physiological functions of d-allulose and the corresponding mechanisms have been studied deeply, and this product has been applied to various foods to enhance food quality and prolong shelf life. In recent years, biotransformation technologies for the production of d-allulose using enzymatic approaches have gained more attention. However, there are few comprehensive reviews on this topic. This review focuses on the recent research advances of d-allulose, including (1) the physiological functions of d-allulose; (2) the major enzyme families used for the biotransformation of d-allulose and their microbial origins; (3) phylogenetic and structural characterization of d-allulose 3-epimerases, and the directed evolution methods for the enzymes; (4) heterologous expression of d-allulose ketose 3-epimerases and biotransformation techniques for d-allulose; and (5) production processes for biotransformation of d-allulose based on the characterized enzymes. Furthermore, the future trends on biosynthesis and applications of d-allulose in food and health industries are discussed and evaluated in this review.
Collapse
Affiliation(s)
- Yu Xia
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; (W.M.); (Z.W.)
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; (Q.C.); (Z.S.); (Y.Q.); (X.L.)
- Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, Wuxi 214122, China
| | - Qianqian Cheng
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; (Q.C.); (Z.S.); (Y.Q.); (X.L.)
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; (W.M.); (Z.W.)
| | - Xiuyu Hu
- China Biotech Fermentation Industry Association, Beijing 100833, China;
| | - Zhen Sun
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; (Q.C.); (Z.S.); (Y.Q.); (X.L.)
| | - Yangyu Qiu
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; (Q.C.); (Z.S.); (Y.Q.); (X.L.)
| | - Ximing Liu
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; (Q.C.); (Z.S.); (Y.Q.); (X.L.)
| | - Zhouping Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; (W.M.); (Z.W.)
- School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; (Q.C.); (Z.S.); (Y.Q.); (X.L.)
- Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, Wuxi 214122, China
| |
Collapse
|
16
|
Gottschalk J, Blaschke L, Aßmann M, Kuballa J, Elling L. Integration of a Nucleoside Triphosphate Regeneration System in the One‐pot Synthesis of UDP‐sugars and Hyaluronic Acid. ChemCatChem 2021. [DOI: 10.1002/cctc.202100462] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Johannes Gottschalk
- Laboratory for Biomaterials Institute of Biotechnology and Helmholtz-Institute for Biomedical Engineering RWTH Aachen University Pauwelsstraße 20 52074 Aachen Germany
| | - Lea Blaschke
- Laboratory for Biomaterials Institute of Biotechnology and Helmholtz-Institute for Biomedical Engineering RWTH Aachen University Pauwelsstraße 20 52074 Aachen Germany
| | - Miriam Aßmann
- Research and Development Department GALAB Laboratories GmbH Am Schleusengraben 7 21029 Hamburg Germany
| | - Jürgen Kuballa
- Research and Development Department GALAB Laboratories GmbH Am Schleusengraben 7 21029 Hamburg Germany
| | - Lothar Elling
- Laboratory for Biomaterials Institute of Biotechnology and Helmholtz-Institute for Biomedical Engineering RWTH Aachen University Pauwelsstraße 20 52074 Aachen Germany
| |
Collapse
|
17
|
Patel SN, Kaushal G, Singh SP. D-Allulose 3-epimerase of Bacillus sp. origin manifests profuse heat-stability and noteworthy potential of D-fructose epimerization. Microb Cell Fact 2021; 20:60. [PMID: 33663507 PMCID: PMC7934257 DOI: 10.1186/s12934-021-01550-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/18/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND D-Allulose is an ultra-low calorie sugar of multifarious health benefits, including anti-diabetic and anti-obesity potential. D-Allulose 3-epimerase family enzymes catalyze biosynthesis of D-allulose via epimerization of D-fructose. RESULTS A novel D-allulose 3-epimerase (DaeB) was cloned from a plant probiotic strain, Bacillus sp. KCTC 13219, and expressed in Bacillus subtilis cells. The purified protein exhibited substantial epimerization activity in a broad pH spectrum, 6.0-11.0. DaeB was able to catalyze D-fructose to D-allulose bioconversion at the temperature range of 35 °C to 70 °C, exhibiting at least 50 % activity. It displaced excessive heat stability, with the half-life of 25 days at 50 °C, and high turnover number (kcat 367 s- 1). The coupling of DaeB treatment and yeast fermentation of 700 g L- 1 D-fructose solution yielded approximately 200 g L- 1 D-allulose, and 214 g L- 1 ethanol. CONCLUSIONS The novel D-allulose 3-epimerase of Bacillus sp. origin discerned a high magnitude of heat stability along with exorbitant epimerization ability. This biocatalyst has enormous potential for the large-scale production of D-allulose.
Collapse
Affiliation(s)
- Satya Narayan Patel
- Center of Innovative and Applied Bioprocessing, S.A.S. Nagar, Sector-81 (Knowledge City), 140306, Mohali, India
| | - Girija Kaushal
- Center of Innovative and Applied Bioprocessing, S.A.S. Nagar, Sector-81 (Knowledge City), 140306, Mohali, India
| | - Sudhir P Singh
- Center of Innovative and Applied Bioprocessing, S.A.S. Nagar, Sector-81 (Knowledge City), 140306, Mohali, India.
| |
Collapse
|