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Wang B, Lei S, Li Q, Luo Y. Production of lactulose from lactose using a novel cellobiose 2-epimerase from Clostridium disporicum. Enzyme Microb Technol 2024; 179:110466. [PMID: 38889605 DOI: 10.1016/j.enzmictec.2024.110466] [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: 03/06/2024] [Revised: 05/17/2024] [Accepted: 06/01/2024] [Indexed: 06/20/2024]
Abstract
Lactulose is a semisynthetic nondigestive sugar derived from lactose, with wide applications in the food and pharmaceutical industries. Its biological production routes which use cellobiose 2-epimerase (C2E) as the key enzyme have attracted widespread attention. In this study, a set of C2Es from different sources were overexpressed in Escherichia coli to produce lactulose. We obtained a novel and highly efficient C2E from Clostridium disporicum (CDC2E) to synthesize lactulose from lactose. The effects of different heat treatment conditions, reaction pH, reaction temperature, and substrate concentrations were investigated. Under the optimum biotransformation conditions, the final concentration of lactulose was up to 1.45 M (496.3 g/L), with a lactose conversion rate of 72.5 %. This study provides a novel C2E for the biosynthesis of lactulose from low-cost lactose.
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Affiliation(s)
- Bohua Wang
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, PR China; Key Laboratory of Agricultural Products Processing and Food Safety in Hunan Province, Changde 415000, PR China; Hunan Provincial 3R Food Innovation and Entrepreneurship Education Center for General Universities, Changde 415000, PR China.
| | - Song Lei
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, PR China; Key Laboratory of Agricultural Products Processing and Food Safety in Hunan Province, Changde 415000, PR China; Hunan Provincial 3R Food Innovation and Entrepreneurship Education Center for General Universities, Changde 415000, PR China
| | - Qingqin Li
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, PR China
| | - Yushuang Luo
- College of Life and Environmental Sciences, Hunan University of Arts and Science, Changde 415000, PR China
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2
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Feng Y, Lyu X, Cong Y, Miao T, Fang B, Zhang C, Shen Q, Matthews M, Fisher AJ, Zhang JZH, Zhang L, Yang R. A precise swaying map for how promiscuous cellobiose-2-epimerase operate bi-reaction. Int J Biol Macromol 2023; 253:127093. [PMID: 37758108 DOI: 10.1016/j.ijbiomac.2023.127093] [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: 08/09/2023] [Revised: 09/24/2023] [Accepted: 09/24/2023] [Indexed: 10/02/2023]
Abstract
Promiscuous enzymes play a crucial role in organism survival and new reaction mining. However, comprehensive mapping of the catalytic and regulatory mechanisms hasn't been well studied due to the characteristic complexity. The cellobiose 2-epimerase from Caldicellulosiruptor saccharolyticus (CsCE) with complex epimerization and isomerization was chosen to comprehensively investigate the promiscuous mechanisms. Here, the catalytic frame of ring-opening, cis-enediol mediated catalysis and ring-closing was firstly determined. To map the full view of promiscuous CE, the structure of CsCE complex with the isomerized product glucopyranosyl-β1,4-fructose was determined. Combined with computational calculation, the promiscuity was proved a precise cooperation of the double subsites, loop rearrangement, and intermediate swaying. The flexible loop was like a gear, whose structural reshaping regulates the sway of the intermediates between the two subsites of H377-H188 and H377-H247, and thus regulates the catalytic directions. The different protonated states of cis-enediol intermediate catalyzed by H188 were the key point for the catalysis. The promiscuous enzyme tends to utilize all elements at hand to carry out the promiscuous functions.
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Affiliation(s)
- Yinghui Feng
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China; State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 214122 Wuxi, China
| | - Xiaomei Lyu
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 214122 Wuxi, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Yalong Cong
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Tingwei Miao
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Bohuan Fang
- Department of Micro/Nano Electronics, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Chuanxi Zhang
- Department of Micro/Nano Electronics, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Qiang Shen
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Melissa Matthews
- Okinawa Institute of Science and Technology, Onna, Okinawa 904-0495, Japan; Department of Chemistry, University of California Davis, Davis, CA 95616, United States; Department of Molecular and Cellular Biology, University of California Davis, Davis, CA 95616, United States
| | - Andrew J Fisher
- Department of Chemistry, University of California Davis, Davis, CA 95616, United States; Department of Molecular and Cellular Biology, University of California Davis, Davis, CA 95616, United States
| | - John Z H Zhang
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China; NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai 200062, China; Department of Chemistry, New York University, New York, NY 10003, United States
| | - Lujia Zhang
- Shanghai Engineering Research Center of Molecular Therapeutics & New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China; NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai 200062, China.
| | - Ruijin Yang
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 214122 Wuxi, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, Wuxi, Jiangsu 214122, China.
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3
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Bitchagno GTM, Nchiozem-Ngnitedem VA, Melchert D, Fobofou SA. Demystifying racemic natural products in the homochiral world. Nat Rev Chem 2022; 6:806-822. [PMID: 36259059 PMCID: PMC9562063 DOI: 10.1038/s41570-022-00431-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2022] [Indexed: 12/03/2022]
Abstract
Natural products possess structural complexity, diversity and chirality with attractive functions and biological activities that have significantly impacted drug discovery initiatives. Chiral natural products are abundant in nature but rarely occur as racemates. The occurrence of natural products as racemates is very intriguing from a biosynthetic point of view; as enzymes are chiral molecules, enzymatic reactions generating natural products should be stereospecific and lead to single-enantiomer products. Despite several reports in the literature describing racemic mixtures of stereoisomers isolated from natural sources, there has not been a comprehensive review of these intriguing racemic natural products. The discovery of many more natural racemates and their potential enzymatic sources in recent years allows us to describe the distribution and chemical diversity of this 'class of natural products' to enrich discussions on biosynthesis. In this Review, we describe the chemical classes, occurrence and distribution of pairs of enantiomers in nature and provide insights about recent advances in analytical methods used for their characterization. Special emphasis is on the biosynthesis, including plausible enzymatic and non-enzymatic formation of natural racemates, and their pharmacological significance.
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Affiliation(s)
- Gabin Thierry M. Bitchagno
- Agrobiosciences, Mohamed IV Polytechnic University, Ben-Guerir, Morocco
- Plant Sciences and Bioeconomy, Rothamsted Research, Harpenden, UK
- Department of Chemistry, University of Dschang, Dschang, Cameroon
| | - Vaderament-A. Nchiozem-Ngnitedem
- Department of Chemistry, University of Dschang, Dschang, Cameroon
- Department of Chemistry, University of Nairobi, Nairobi, Kenya
- Institute of Chemistry, University of Potsdam, Potsdam-Golm, Germany
| | - Dennis Melchert
- Institute of Pharmaceutical Biology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Serge Alain Fobofou
- Institute of Pharmaceutical Biology, Technische Universität Braunschweig, Braunschweig, Germany
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX USA
- Texas Children’s Microbiome Center, Department of Pathology, Texas Children’s Hospital, Houston, TX USA
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4
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Lv QB, Li S, Zhang Y, Guo R, Wang YC, Peng Y, Zhang XX. A thousand metagenome-assembled genomes of Akkermansia reveal phylogroups and geographical and functional variations in the human gut. Front Cell Infect Microbiol 2022; 12:957439. [PMID: 35982777 PMCID: PMC9378777 DOI: 10.3389/fcimb.2022.957439] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 07/11/2022] [Indexed: 01/02/2023] Open
Abstract
Akkermansia muciniphila has long been considered to be the only Akkermansia species in the human gut and has been extensively studied. The present study revealed the genomic architecture of Akkermansia in the human gut by analyzing 1,126 near-complete metagenome-assembled genomes, 84 publicly available genomes, and 1 newly sequenced Akkermansia glycaniphila strain from the human gut. We found that 1) the genomes of Akkermansia were clustered into four phylogroups with distinct interspecies similarity and different genomic characteristics and 2) A. glycaniphila GP37, a strain of Akkermansia, was isolated from the human gut, whereas previously, it had only been found in python. Amuc III was present in the Chinese population, and Amuc IV was mainly distributed in Western populations. A large number of gene functions, pathways, and carbohydrate-active enzymes were specifically associated with phylogroups. Our findings based on over a thousand genomes strengthened our previous knowledge and provided new insights into the population structure and ecology of Akkermansia in the human gut.
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Affiliation(s)
- Qing-Bo Lv
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, China
- Puensum Genetech Institute, Wuhan, China
| | | | - Yue Zhang
- Puensum Genetech Institute, Wuhan, China
| | | | - Yan-Chun Wang
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
| | - Yongzheng Peng
- Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China
- *Correspondence: Yongzheng Peng, ; Xiao-Xuan Zhang,
| | - Xiao-Xuan Zhang
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, China
- *Correspondence: Yongzheng Peng, ; Xiao-Xuan Zhang,
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Wang M, Wang L, Lyu X, Hua X, Goddard JM, Yang R. Lactulose production from lactose isomerization by chemo-catalysts and enzymes: Current status and future perspectives. Biotechnol Adv 2022; 60:108021. [PMID: 35901861 DOI: 10.1016/j.biotechadv.2022.108021] [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: 03/14/2022] [Revised: 07/02/2022] [Accepted: 07/17/2022] [Indexed: 11/29/2022]
Abstract
Lactulose, a semisynthetic nondigestive disaccharide with versatile applications in the food and pharmaceutical industries, has received increasing interest due to its significant health-promoting effects. Currently, industrial lactulose production is exclusively carried out by chemical isomerization of lactose via the Lobry de Bruyn-Alberda van Ekenstein (LA) rearrangement, and much work has been directed toward improving the conversion efficiency in terms of lactulose yield and purity by using new chemo-catalysts and integrated catalytic-purification systems. Lactulose can also be produced by an enzymatic route offering a potentially greener alternative to chemo-catalysis with fewer side products. Compared to the controlled trans-galactosylation by β-galactosidase, directed isomerization of lactose with high isomerization efficiency catalyzed by the most efficient lactulose-producing enzyme, cellobiose 2-epimerase (CE), has gained much attention in recent decades. To further facilitate the industrial translation of CE-based lactulose biotransformation, numerous studies have been reported on improving biocatalytic performance through enzyme mediated molecular modification. This review summarizes recent developments in the chemical and enzymatic production of lactulose. Related catalytic mechanisms are also highlighted and described in detail. Emerging techniques that aimed at advancing lactulose production, such as the boronate affinity-based technique and molecular biological techniques, are reviewed. Finally, perspectives on challenges and opportunities in lactulose production and purification are also discussed.
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Affiliation(s)
- Mingming Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 214122 Wuxi, China; College of Food Science and Engineering, Ocean University of China, Qingdao, Shandong Province 266003, China; Department of Food Science, Cornell University, Ithaca, NY 14853, USA
| | - Lu Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 214122 Wuxi, China
| | - Xiaomei Lyu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 214122 Wuxi, China
| | - Xiao Hua
- State Key Laboratory of Food Science and Technology, Jiangnan University, 214122 Wuxi, China
| | - Julie M Goddard
- Department of Food Science, Cornell University, Ithaca, NY 14853, USA.
| | - Ruijin Yang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 214122 Wuxi, China.
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6
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Multi-enzyme systems and recombinant cells for synthesis of valuable saccharides: Advances and perspectives. Biotechnol Adv 2019; 37:107406. [DOI: 10.1016/j.biotechadv.2019.06.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 05/30/2019] [Accepted: 06/08/2019] [Indexed: 02/07/2023]
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A Family of Dual-Activity Glycosyltransferase-Phosphorylases Mediates Mannogen Turnover and Virulence in Leishmania Parasites. Cell Host Microbe 2019; 26:385-399.e9. [DOI: 10.1016/j.chom.2019.08.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/24/2019] [Accepted: 08/15/2019] [Indexed: 01/08/2023]
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8
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Bertucci M, Calusinska M, Goux X, Rouland-Lefèvre C, Untereiner B, Ferrer P, Gerin PA, Delfosse P. Carbohydrate Hydrolytic Potential and Redundancy of an Anaerobic Digestion Microbiome Exposed to Acidosis, as Uncovered by Metagenomics. Appl Environ Microbiol 2019; 85:e00895-19. [PMID: 31152018 PMCID: PMC6643232 DOI: 10.1128/aem.00895-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 05/26/2019] [Indexed: 12/22/2022] Open
Abstract
Increased hydrolysis of easily digestible biomass may lead to acidosis of anaerobic reactors and decreased methane production. Previously, it was shown that the structure of microbial communities changed during acidosis; however, once the conditions are back to optimal, biogas (initially CO2) production quickly restarts. This suggests the retention of the community functional redundancy during the process failure. In this study, with the use of metagenomics and downstream bioinformatics analyses, we characterize the carbohydrate hydrolytic potential of the microbial community, with a special focus on acidosis. To that purpose, carbohydrate-active enzymes were identified, and to further link the community hydrolytic potential with key microbes, bacterial genomes were reconstructed. In addition, we characterized biochemically the specificity and activity of selected enzymes, thus verifying the accuracy of the in silico predictions. The results confirm the retention of the community hydrolytic potential during acidosis and indicate Bacteroidetes to be largely involved in biomass degradation. Bacteroidetes showed higher diversity and genomic content of carbohydrate hydrolytic enzymes that might favor the dominance of this phylum over other bacteria in some anaerobic reactors. The combination of bioinformatic analyses and activity tests enabled us to propose a model of acetylated glucomannan degradation by BacteroidetesIMPORTANCE The enzymatic hydrolysis of lignocellulosic biomass is mainly driven by the action of carbohydrate-active enzymes. By characterizing the gene profiles at the different stages of the anaerobic digestion experiment, we showed that the microbiome retains its hydrolytic functional redundancy even during severe acidosis, despite significant changes in taxonomic composition. By analyzing reconstructed bacterial genomes, we demonstrate that Bacteroidetes hydrolytic gene diversity likely favors the abundance of this phylum in some anaerobic digestion systems. Further, we observe genetic redundancy within the Bacteroidetes group, which accounts for the preserved hydrolytic potential during acidosis. This work also uncovers new polysaccharide utilization loci involved in the deconstruction of various biomasses and proposes the model of acetylated glucomannan degradation by Bacteroidetes Acetylated glucomannan-enriched biomass is a common substrate for many industries, including pulp and paper production. Using naturally evolved cocktails of enzymes for biomass pretreatment could be an interesting alternative to the commonly used chemical pretreatments.
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Affiliation(s)
- Marie Bertucci
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
- Laboratory of Bioengineering, Earth and Life Institute, Applied Microbiology, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Magdalena Calusinska
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
| | - Xavier Goux
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
| | - Corinne Rouland-Lefèvre
- Institute of Ecology and Environmental Sciences, Research Institute Development, Sorbonne Universités, Bondy, France
| | - Boris Untereiner
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
| | - Pau Ferrer
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
| | - Patrick A Gerin
- Laboratory of Bioengineering, Earth and Life Institute, Applied Microbiology, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Philippe Delfosse
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
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Saburi W, Sato S, Hashiguchi S, Muto H, Iizuka T, Mori H. Enzymatic characteristics of d-mannose 2-epimerase, a new member of the acylglucosamine 2-epimerase superfamily. Appl Microbiol Biotechnol 2019; 103:6559-6570. [DOI: 10.1007/s00253-019-09944-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/20/2019] [Accepted: 05/25/2019] [Indexed: 11/30/2022]
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10
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The human gut Firmicute Roseburia intestinalis is a primary degrader of dietary β-mannans. Nat Commun 2019; 10:905. [PMID: 30796211 PMCID: PMC6385246 DOI: 10.1038/s41467-019-08812-y] [Citation(s) in RCA: 176] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 02/03/2019] [Indexed: 12/11/2022] Open
Abstract
β-Mannans are plant cell wall polysaccharides that are commonly found in human diets. However, a mechanistic understanding into the key populations that degrade this glycan is absent, especially for the dominant Firmicutes phylum. Here, we show that the prominent butyrate-producing Firmicute Roseburia intestinalis expresses two loci conferring metabolism of β-mannans. We combine multi-“omic” analyses and detailed biochemical studies to comprehensively characterize loci-encoded proteins that are involved in β-mannan capturing, importation, de-branching and degradation into monosaccharides. In mixed cultures, R. intestinalis shares the available β-mannan with Bacteroides ovatus, demonstrating that the apparatus allows coexistence in a competitive environment. In murine experiments, β-mannan selectively promotes beneficial gut bacteria, exemplified by increased R. intestinalis, and reduction of mucus-degraders. Our findings highlight that R. intestinalis is a primary degrader of this dietary fiber and that this metabolic capacity could be exploited to selectively promote key members of the healthy microbiota using β-mannan-based therapeutic interventions. How dietary β-mannans are utilized by gut Gram-positive bacteria is unclear. Here, the authors uncover the enzymatic pathway for β-mannan metabolism in Roseburia intestinalis and show that these polysaccharides promote beneficial gut bacteria, highlighting a potential for β-mannan-based therapeutic interventions.
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Chen Q, Xiao Y, Zhang W, Zhang T, Jiang B, Stressler T, Fischer L, Mu W. Current research on cellobiose 2-epimerase: Enzymatic properties, mechanistic insights, and potential applications in the dairy industry. Trends Food Sci Technol 2018. [DOI: 10.1016/j.tifs.2018.09.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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12
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Kuschel B, Seitl I, Glück C, Mu W, Jiang B, Stressler T, Fischer L. Hidden Reaction: Mesophilic Cellobiose 2-Epimerases Produce Lactulose. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:2530-2539. [PMID: 28252294 DOI: 10.1021/acs.jafc.6b05599] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Lactulose (4-O-β-d-galactopyranosyl-d-fructofuranose) is a prebiotic sugar derived from the milk sugar lactose (4-O-β-d-galactopyranosyl-d-glucopyranose). In our study we observed for the first time that known cellobiose 2-epimerases (CEs; EC 5.1.3.11) from mesophilic microorganisms were generally able to catalyze the isomerization reaction of lactose into lactulose. Commonly, CEs catalyze the C2-epimerization of d-glucose and d-mannose moieties at the reducing end of β-1,4-glycosidic-linked oligosaccharides. Thus, epilactose (4-O-β-d-galactopyranosyl-d-mannopyranose) is formed with lactose as substrate. So far, only four CEs, exclusively from thermophilic microorganisms, have been reported to additionally catalyze the isomerization reaction of lactose into lactulose. The specific isomerization activity of the seven CEs in this study ranged between 8.7 ± 0.1 and 1300 ± 37 pkat/mg. The results indicate that very likely all CEs are able to catalyze both the epimerization as well as the isomerization reaction, whereby the latter is performed at a comparatively much lower reaction rate.
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Affiliation(s)
- Beatrice Kuschel
- Department of Biotechnology and Enzyme Science, Institute of Food Science and Biotechnology, University of Hohenheim , Garbenstrasse 25, D-70599, Stuttgart, Germany
| | - Ines Seitl
- Department of Biotechnology and Enzyme Science, Institute of Food Science and Biotechnology, University of Hohenheim , Garbenstrasse 25, D-70599, Stuttgart, Germany
| | - Claudia Glück
- Department of Biotechnology and Enzyme Science, Institute of Food Science and Biotechnology, University of Hohenheim , Garbenstrasse 25, D-70599, Stuttgart, Germany
| | - Wanmeng Mu
- 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
| | - Timo Stressler
- Department of Biotechnology and Enzyme Science, Institute of Food Science and Biotechnology, University of Hohenheim , Garbenstrasse 25, D-70599, Stuttgart, Germany
| | - Lutz Fischer
- Department of Biotechnology and Enzyme Science, Institute of Food Science and Biotechnology, University of Hohenheim , Garbenstrasse 25, D-70599, Stuttgart, Germany
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13
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Reaction investigation of lactulose-producing cellobiose 2-epimerases under operational relevant conditions. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.molcatb.2016.11.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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