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Vaze R, Gadde S, Rathi A, Rathi VL, Jadhav S. Catalytic action of alternansucrase on sucrose under in vitro simulated gastric conditions. Carbohydr Res 2024; 542:109202. [PMID: 38954850 DOI: 10.1016/j.carres.2024.109202] [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: 04/22/2024] [Revised: 06/21/2024] [Accepted: 06/28/2024] [Indexed: 07/04/2024]
Abstract
Alternansucrase, a glucosyltransferase, is currently used to produce slowly digestible alternan oligosaccharides or maltooligosaccharides from sucrose. These oligosaccharides are popular for food fortification to lower postprandial glucose levels. This study aimed to explore the enzymatic reaction of alternansucrase in simulated in vitro gastric reaction conditions. Under the studied conditions, SucroSEB (a model enzyme for alternansucrase) hydrolyzed the sucrose and transglycosylated the glucose to produce glucans, both in the absence and presence of acceptors. The preference of the acceptor was maltose˃ raffinose˃ lactose. The rate of sucrose hydrolysis was significantly higher in the presence of maltose (p = 0.024). The glucans formed during the reaction included oligomers (DP 3-10) and polymers (DP ≥ 11), both of which increased over time. These glucans contained α-1,3 and α-1,6 glycosidic linkages, confirmed by 1H and 13C NMR. They were slowly and partially digestible in the presence of rat intestinal extract in contrast to the complete and rapid digestion of starch. The glucans formed after a longer gastric reaction time exhibited higher dietary fiber potential (19.145 ± 4.77 %; 60 min) compared to those formed during the initial phase (2.765 ± 0.19 %; 15 min). Overall, this study demonstrated the efficacy of SucroSEB in converting sucrose to slowly and partially digestible glucans under simulated in vitro gastric conditions.
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Affiliation(s)
- Rutuja Vaze
- Human Nutrition Department, Advanced Enzymes Technologies Ltd., Louiswadi, Thane, 400604, India
| | - Sriteja Gadde
- Human Nutrition Department, Advanced Enzymes Technologies Ltd., Louiswadi, Thane, 400604, India
| | - Abhijit Rathi
- Human Nutrition Department, Advanced Enzymes Technologies Ltd., Louiswadi, Thane, 400604, India
| | - V L Rathi
- Human Nutrition Department, Advanced Enzymes Technologies Ltd., Louiswadi, Thane, 400604, India
| | - Swati Jadhav
- Human Nutrition Department, Advanced Enzymes Technologies Ltd., Louiswadi, Thane, 400604, India.
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2
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Characterization of the (Engineered) Branching Sucrase GtfZ-CD2 from Apilactobacillus kunkeei for Efficient Glucosylation of Benzenediol Compounds. Appl Environ Microbiol 2022; 88:e0103122. [PMID: 35924943 PMCID: PMC9397098 DOI: 10.1128/aem.01031-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Branching sucrases, a subfamily of Glycoside Hydrolase family (GH70), display transglycosidase activity using sucrose as donor substrate to catalyze glucosylation reaction in the presence of suitable acceptor substrates. In this study, the (α1→3) branching sucrase GtfZ-CD2 from Apilactobacillus kunkeei DSM 12361 was demonstrated to glucosylate benzenediol compounds (i.e., catechol, resorcinol, and hydroquinone) to form monoglucoside and diglucoside products. The production and yield of catechol glucosylated products were significantly higher than that of resorcinol and hydroquinone, revealing a preference for adjacent aromatic hydroxyl groups in glucosylation. Amino residues around acceptor substrate binding subsite +1 were targeted for semirational mutagenesis, yielding GtfZ-CD2 variants with improved resorcinol and hydroquinone glucosylation. Mutant L1560Y with improved hydroquinone mono-glucosylated product synthesis allowed enzymatic conversion of hydroquinone into α-arbutin. This study thus revealed the high potential of GH70 branching sucrases for glucosylating noncarbohydrate molecules. IMPORTANCE Glycosylation represents one of the most important ways to expand the diversity of natural products and improve their physico-chemical properties. Aromatic polyphenol compounds widely found in plants are reported to exhibit various remarkable biological activities; however, they generally suffer from low solubility and stability, which can be improved by glycosylation. Our present study on the glucosylation of benzenediol compounds by GH70 branching sucrase GtfZ-CD2 and its semirational engineering to improve the glucosylation efficiency provides insight into the mechanism of acceptor substrates binding and its glucosylation selectivity. The results demonstrate the potential of using branching sucrase as an effective enzymatic glucosylation tool.
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Li X, Meng X, de Leeuw TC, Te Poele EM, Pijning T, Dijkhuizen L, Liu W. Enzymatic glucosylation of polyphenols using glucansucrases and branching sucrases of glycoside hydrolase family 70. Crit Rev Food Sci Nutr 2021:1-21. [PMID: 34907830 DOI: 10.1080/10408398.2021.2016598] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Polyphenols exhibit various beneficial biological activities and represent very promising candidates as active compounds for food industry. However, the low solubility, poor stability and low bioavailability of polyphenols have severely limited their industrial applications. Enzymatic glycosylation is an effective way to improve the physicochemical properties of polyphenols. As efficient transglucosidases, glycoside hydrolase family 70 (GH70) glucansucrases naturally catalyze the synthesis of polysaccharides and oligosaccharides from sucrose. Notably, GH70 glucansucrases show broad acceptor substrate promiscuity and catalyze the glucosylation of a wide range of non-carbohydrate hydroxyl group-containing molecules, including benzenediol, phenolic acids, flavonoids and steviol glycosides. Branching sucrase enzymes, a newly established subfamily of GH70, are shown to possess a broader acceptor substrate binding pocket that acts efficiently for glucosylation of larger size polyphenols such as flavonoids. Here we present a comprehensive review of glucosylation of polyphenols using GH70 glucansucrase and branching sucrases. Their catalytic efficiency, the regioselectivity of glucosylation and the structure of generated products are described for these reactions. Moreover, enzyme engineering is effective for improving their catalytic efficiency and product specificity. The combined information provides novel insights on the glucosylation of polyphenols by GH70 glucansucrases and branching sucrases, and may promote their applications.
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Affiliation(s)
- Xiaodan Li
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, People's Republic of China
| | - Xiangfeng Meng
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, People's Republic of China
| | | | | | - Tjaard Pijning
- Biomolecular X-ray Crystallography, University of Groningen, Groningen, The Netherlands
| | | | - Weifeng Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, People's Republic of China
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Wangpaiboon K, Sitthiyotha T, Chunsrivirot S, Charoenwongpaiboon T, Pichyangkura R. Unravelling Regioselectivity of Leuconostoc citreum ABK-1 Alternansucrase by Acceptor Site Engineering. Int J Mol Sci 2021; 22:3229. [PMID: 33810084 PMCID: PMC8005217 DOI: 10.3390/ijms22063229] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/16/2021] [Accepted: 03/18/2021] [Indexed: 01/24/2023] Open
Abstract
Alternansucrase (ALT, EC 2.4.1.140) is a glucansucrase that can generate α-(1,3/1,6)-linked glucan from sucrose. Previously, the crystal structure of the first alternansucrase from Leuconostoc citreum NRRL B-1355 was successfully elucidated; it showed that alternansucrase might have two acceptor subsites (W675 and W543) responsible for the formation of alternating linked glucan. This work aimed to investigate the primary acceptor subsite (W675) by saturated mutagenesis using Leuconostoc citreum ABK-1 alternansucrase (LcALT). The substitution of other residues led to loss of overall activity, and formation of an alternan polymer with a nanoglucan was maintained when W675 was replaced with other aromatic residues. Conversely, substitution by nonaromatic residues led to the synthesis of oligosaccharides. Mutations at W675 could potentially cause LcALT to lose control of the acceptor molecule binding via maltose-acceptor reaction-as demonstrated by results from molecular dynamics simulations of the W675A variant. The formation of α-(1,2), α-(1,3), α-(1,4), and α-(1,6) linkages were detected from products of the W675A mutant. In contrast, the wild-type enzyme strictly synthesized α-(1,6) linkage on the maltose acceptor. This study examined the importance of W675 for transglycosylation, processivity, and regioselectivity of glucansucrases. Engineering glucansucrase active sites is one of the essential approaches to green tools for carbohydrate modification.
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Affiliation(s)
- Karan Wangpaiboon
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand; (K.W.); (S.C.)
| | - Thassanai Sitthiyotha
- Structural and Computational Biology Research Unit, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand;
| | - Surasak Chunsrivirot
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand; (K.W.); (S.C.)
- Structural and Computational Biology Research Unit, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand;
| | | | - Rath Pichyangkura
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand; (K.W.); (S.C.)
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Liu M, Cai M, Ding P. Oligosaccharides from Traditional Chinese Herbal Medicines: A Review of Chemical Diversity and Biological Activities. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2021; 49:577-608. [PMID: 33730992 DOI: 10.1142/s0192415x21500269] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
Most of traditional Chinese herbal medicine (TCHM) substances come from medicinal plants, among which oligosaccharides have gradually attracted widespread attention at home and abroad due to their important biological activities and great medicinal potential. Numerous in vitro and in vivo experiments exhibited that oligosaccharides possess various activities, such as antitumor, anti-oxidation, modulate the gut microflora, anti-inflammatory, anti-infection, and immune-regulatory activities. Generally, biological activities are closely related to chemical structures, including molecular weight, monosaccharide composition, glycosidic bond connection, etc. The structural analysis of oligosaccharides is an important basis for studying their structure-activity relationship, but the structural diversity and complexity of carbohydrate compounds limit the study of oligosaccharides activities. Understanding the structures and biological functions of oligosaccharides is important for the development of new bioactive substances with natural oligosaccharides. This review provides a systematic introduction of the current knowledge of the chemical structures and biological activities of oligosaccharides. Most importantly, the reported chemical characteristics and biological activities of the famous TCHM oligosaccharides were briefly summarized, including Morinda officinalis, Rehmannia glutinosa, Arctium lappa, Polygala tenuifolia, Panax ginseng, Lycium barbarum and Astragalus membranaceus. TCHM oligosaccharides play an important role in nutrition, health care, disease diagnosis and prevention as well as have broad application prospects in the field of medicine.
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Affiliation(s)
- Mengyun Liu
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, 232 Waihuan East Road, Panyu District, Guangzhou 510006, P. R. China
| | - Miaomiao Cai
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, 232 Waihuan East Road, Panyu District, Guangzhou 510006, P. R. China
| | - Ping Ding
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, 232 Waihuan East Road, Panyu District, Guangzhou 510006, P. R. China
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Apolinar-Valiente R, Williams P, Doco T. Recent advances in the knowledge of wine oligosaccharides. Food Chem 2020; 342:128330. [PMID: 33067045 DOI: 10.1016/j.foodchem.2020.128330] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 10/05/2020] [Accepted: 10/05/2020] [Indexed: 12/01/2022]
Abstract
Oligosaccharides are carbohydrates with a low polymerization degree containing between three and fifteen monosaccharide residues covalently linked through glycosidic bonds. Oligosaccharides are related to plant defense responses and possess beneficial attributes for human health. Research has focused in wine oligosaccharides only in the last decade. In this paper, a summary of these works is provided. They include: (i) wine oligosaccharides origins, (ii) techniques for isolating oligosaccharide fraction and determining their content, composition and structure, (iii) their dependence on the grape origin and cultivar and winemaking process, and (iv) the connection between oligosaccharides and wine sensorial attributes. Further research is required regarding the impact of agricultural aspects and winemaking techniques on wine oligosaccharides. The knowledge concerning their influence on sensorial and physicochemical properties of wines and on human health should also be improved. The implementation of laboratory methods will provide better understanding of these compounds and their performance within wine's matrix.
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Affiliation(s)
- Rafael Apolinar-Valiente
- INRAE, Supagro, UM, Joint Research Unit 1083, Sciences for Enology, Biomolecules of Interest in Oenology (B.I.O.) Research Team, 2 Place Pierre Viala, F-34060 Montpellier, France.
| | - Pascale Williams
- INRAE, Supagro, UM, Joint Research Unit 1083, Sciences for Enology, Biomolecules of Interest in Oenology (B.I.O.) Research Team, 2 Place Pierre Viala, F-34060 Montpellier, France.
| | - Thierry Doco
- INRAE, Supagro, UM, Joint Research Unit 1083, Sciences for Enology, Biomolecules of Interest in Oenology (B.I.O.) Research Team, 2 Place Pierre Viala, F-34060 Montpellier, France.
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7
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Extracellular polysaccharides produced by bacteria of the Leuconostoc genus. World J Microbiol Biotechnol 2020; 36:161. [DOI: 10.1007/s11274-020-02937-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 09/16/2020] [Indexed: 10/23/2022]
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İspirli H, Colquhoun IJ, Şahin E, Sagdic O, Dertli E. Preparation of gentiobiose-derived oligosaccharides by glucansucrase E81 and determination of prebiotic and immune-modulatory functions. Carbohydr Res 2019; 486:107837. [PMID: 31655418 DOI: 10.1016/j.carres.2019.107837] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 10/14/2019] [Accepted: 10/15/2019] [Indexed: 10/25/2022]
Abstract
Gentiobiose-derived oligosaccharides were synthesized by the acceptor reaction of glucansucrase E81 obtained from Lactobacillus reuteri E81 with sucrose and gentiobiose as donor-acceptor sugars, respectively. The reaction products were monitored by TLC analysis and gentiobiose-derived oligosaccharides up to DP 8 were formed during the acceptor reaction as determined by ESI-MS/MS analysis. The glycosylation of the gentiobiose with α-(1 → 6) linkages and α-(1 → 3) linkages was shown by 1H and 13C NMR analysis confirming the structure of these gentiobiose-derived oligosaccharides. The in vitro prebiotic function of the oligosaccharides was determined in which probiotic strains were stimulated whereas no growth was observed in pathogen strains. Gentiobiose-derived oligosaccharides showed immune-modulatory functions in vitro and triggered the production of IL-4, IL12 and TNF-α cytokines in HT29 cells in a dose dependent manner. This study showed the production and functional characterisation of gentiobiose-derived oligosaccharides establishing a promising avenue for future applications.
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Affiliation(s)
- Hümeyra İspirli
- Yıldız Technical University, Chemical and Metallurgical Engineering Faculty, Department of Food Engineering, Istanbul, 34000, Turkey
| | - Ian J Colquhoun
- Analytical Sciences Unit, Quadram Institute Bioscience, Norwich, UK
| | - Engin Şahin
- Department of Food Engineering, Faculty of Engineering, Bayburt University, Bayburt, 69000, Turkey
| | - Osman Sagdic
- Yıldız Technical University, Chemical and Metallurgical Engineering Faculty, Department of Food Engineering, Istanbul, 34000, Turkey
| | - Enes Dertli
- Department of Food Engineering, Faculty of Engineering, Bayburt University, Bayburt, 69000, Turkey.
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9
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İspirli H, Dertli E. Production of mannose-containing oligosaccharides by glucansucrase E81 and determination of their functional characteristics. BIOCATAL BIOTRANSFOR 2019. [DOI: 10.1080/10242422.2019.1661384] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Hümeyra İspirli
- Chemical and Metallurgical Engineering Faculty, Department of Food Engineering, Yıldız Technical University, Istanbul, Turkey
| | - Enes Dertli
- Department of Food Engineering, Faculty of Engineering, Bayburt University, Bayburt, Turkey
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10
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Low molecular weight dextran production by Leuconostoc mesenteroides strains: Optimization of a new culture medium and the rheological assessments. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.bcdf.2019.100181] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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11
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Zhao C, Wu Y, Liu X, Liu B, Cao H, Yu H, Sarker SD, Nahar L, Xiao J. Functional properties, structural studies and chemo-enzymatic synthesis of oligosaccharides. Trends Food Sci Technol 2017. [DOI: 10.1016/j.tifs.2017.06.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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12
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C. K. Rajendran SR, Okolie CL, Udenigwe CC, Mason B. Structural features underlying prebiotic activity of conventional and potential prebiotic oligosaccharides in food and health. J Food Biochem 2017. [DOI: 10.1111/jfbc.12389] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Subin R. C. K. Rajendran
- Department of Plant, Food, and Environmental Sciences, Faculty of Agriculture; Dalhousie University; Nova Scotia B2N5E3, Canada
- Verschuren Centre for Sustainability in Energy and the Environment; Cape Breton University; Nova Scotia B1P6L2, Canada
| | - Chigozie Louis Okolie
- Department of Plant, Food, and Environmental Sciences, Faculty of Agriculture; Dalhousie University; Nova Scotia B2N5E3, Canada
- Verschuren Centre for Sustainability in Energy and the Environment; Cape Breton University; Nova Scotia B1P6L2, Canada
| | - Chibuike C. Udenigwe
- School of Nutrition Sciences, Faculty of Health Sciences; University of Ottawa; Ontario K1N6N5, Canada
| | - Beth Mason
- Verschuren Centre for Sustainability in Energy and the Environment; Cape Breton University; Nova Scotia B1P6L2, Canada
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Belorkar SA, Gupta AK. Oligosaccharides: a boon from nature's desk. AMB Express 2016; 6:82. [PMID: 27699701 PMCID: PMC5047869 DOI: 10.1186/s13568-016-0253-5] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 09/15/2016] [Indexed: 11/10/2022] Open
Abstract
This article reviews the varied sources of oligosaccharides available in nature as silent health promoting, integral ingredients of plants as well as animal products like honey and milk. The article focuses on exotic and unfamiliar oligosaccharides like Galactooligosaccharides, Lactulose derived Galactooligosaccharides, Xylooligosaccharides, Arabinooligosaccharides and algae derived Marine oligosaccharides along with the most acknowledged prebiotic fructooligosaccharides. The oligosaccharides are named as on the grounds of the monomeric units forming oligomers with functional properties. The chemical structures, natural sources, microbial enzyme mediated synthesis and physiological effects are discussed. An elaborate account of the different types of oligosaccharides with special reference to fructooligosaccharides are presented. Finally, the profound health benefits of oligosaccharides are rigourously discussed limelighting its positive physiological sequel.
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Affiliation(s)
- Seema A. Belorkar
- Department of Microbiology and Bioinformatics, Bilaspur University, 206, Budhiya complex, Sarkanda, Bilaspur, Chhattisgarh 495004 India
| | - A. K. Gupta
- Pt. Ravishankar Shukla University, Raipur, CG 492010 India
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Structural determinants of alternating (α1 → 4) and (α1 → 6) linkage specificity in reuteransucrase of Lactobacillus reuteri. Sci Rep 2016; 6:35261. [PMID: 27748434 PMCID: PMC5066211 DOI: 10.1038/srep35261] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 09/26/2016] [Indexed: 12/29/2022] Open
Abstract
The glucansucrase GTFA of Lactobacillus reuteri 121 produces an α-glucan (reuteran) with a large amount of alternating (α1 → 4) and (α1 → 6) linkages. The mechanism of alternating linkage formation by this reuteransucrase has remained unclear. GTFO of the probiotic bacterium Lactobacillus reuteri ATCC 55730 shows a high sequence similarity (80%) with GTFA of L. reuteri 121; it also synthesizes an α-glucan with (α1 → 4) and (α1 → 6) linkages, but with a clearly different ratio compared to GTFA. In the present study, we show that residues in loop977 (970DGKGYKGA977) and helix α4 (1083VSLKGA1088) are main determinants for the linkage specificity difference between GTFO and GTFA, and hence are important for the synthesis of alternating (α1 → 4) and (α1 → 6) linkages in GTFA. More remote acceptor substrate binding sites (i.e.+3) are also involved in the determination of alternating linkage synthesis, as shown by structural analysis of the oligosaccharides produced using panose and maltotriose as acceptor substrate. Our data show that the amino acid residues at acceptor substrate binding sites (+1, +2, +3…) together form a distinct physicochemical micro-environment that determines the alternating (α1 → 4) and (α1 → 6) linkages synthesis in GTFA.
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Xu L, Zhang J. Bacterial glucans: production, properties, and applications. Appl Microbiol Biotechnol 2016; 100:9023-9036. [DOI: 10.1007/s00253-016-7836-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 08/23/2016] [Accepted: 08/24/2016] [Indexed: 11/29/2022]
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16
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Meng X, Pijning T, Tietema M, Dobruchowska JM, Yin H, Gerwig GJ, Kralj S, Dijkhuizen L. Characterization of the glucansucrase GTF180 W1065 mutant enzymes producing polysaccharides and oligosaccharides with altered linkage composition. Food Chem 2016; 217:81-90. [PMID: 27664611 DOI: 10.1016/j.foodchem.2016.08.087] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Revised: 08/23/2016] [Accepted: 08/24/2016] [Indexed: 02/03/2023]
Abstract
Exopolysaccharides produced by lactic acid bacteria are extensively used for food applications. Glucansucrase enzymes of lactic acid bacteria use sucrose to catalyze the synthesis of α-glucans with different linkage compositions, size and physico-chemical properties. Crystallographic studies of GTF180-ΔN show that at the acceptor binding sites +1 and +2, residue W1065 provides stacking interactions to the glucosyl moiety. However, the detailed functional roles of W1065 have not been elucidated. We performed random mutagenesis targeting residue W1065 of GTF180-ΔN, resulting in the generation of 10 mutant enzymes that were characterized regarding activity and product specificity. Characterization of mutant enzymes showed that residue W1065 is critical for the activity of GTF180-ΔN. Using sucrose, and sucrose (donor) plus maltose (acceptor) as substrates, the mutant enzymes synthesized polysaccharides and oligosaccharides with changed linkage composition. The stacking interaction of an aromatic residue at position 1065 is essential for polysaccharide synthesis.
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Affiliation(s)
- Xiangfeng Meng
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
| | - Tjaard Pijning
- Biophysical Chemistry, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
| | - Martin Tietema
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
| | - Justyna M Dobruchowska
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
| | - Huifang Yin
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
| | - Gerrit J Gerwig
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
| | - Slavko Kralj
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
| | - Lubbert Dijkhuizen
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
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17
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Kothari D, Goyal A. Gentio-oligosaccharides from Leuconostoc mesenteroides NRRL B-1426 dextransucrase as prebiotics and as a supplement for functional foods with anti-cancer properties. Food Funct 2016; 6:604-11. [PMID: 25524369 DOI: 10.1039/c4fo00802b] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Gentio-oligosaccharides (GnOS) were synthesized by the acceptor reaction of dextransucrase from Leuconostoc mesenteroides NRRL B-1426 with gentiobiose and sucrose. GnOS were purified by gel permeation chromatography using a Bio-Gel P-2 column and identified by mass spectrometry. The purified GnOS (degree of polymerization ≥3) were investigated for their in vitro prebiotic and cytotoxic activity. GnOS exhibited a significantly lower degree of digestibility of 18.1% by simulated human gastric juice (pH 1.0) and 7.1% by human α-amylase (pH 7.0) after 6 h, whereas inulin, a standard prebiotic, showed 39.7% and 12.8% of digestibility, respectively. The prebiotic score showed that GnOS significantly supported the growth of probiotics such as Bifidobacterium infantis and Lactobacillus acidophilus and was comparable to that of inulin. The selective inhibitory effect of GnOS on human colon carcinoma (HT-29) cells revealed its potential as an anti-cancer agent that can serve as a functional food additive for the benefit of human health.
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Affiliation(s)
- Damini Kothari
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781 039, Assam, India.
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Zannini E, Waters DM, Coffey A, Arendt EK. Production, properties, and industrial food application of lactic acid bacteria-derived exopolysaccharides. Appl Microbiol Biotechnol 2015; 100:1121-1135. [PMID: 26621802 DOI: 10.1007/s00253-015-7172-2] [Citation(s) in RCA: 217] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 11/08/2015] [Accepted: 11/11/2015] [Indexed: 11/25/2022]
Abstract
Exopolysaccharides (EPS)-producing lactic acid bacteria (LAB) are industrially important microorganisms in the development of functional food products and are used as starter cultures or coadjutants to develop fermented foods. There is large variability in EPS production by LAB in terms of chemical composition, quantity, molecular size, charge, presence of side chains, and rigidity of the molecules. The main body of the review will cover practical aspects concerning the structural diversity structure of EPS, and their concrete application in food industries is reported in details. To strengthen the food application and process feasibility of LAB EPS at industrial level, a future academic research should be combined with industrial input to understand the technical shortfalls that EPS can address.
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Affiliation(s)
- Emanuele Zannini
- School of Food and Nutritional Sciences, University College Cork, Western Road, Cork, Ireland
| | - Deborah M Waters
- School of Food and Nutritional Sciences, University College Cork, Western Road, Cork, Ireland
| | - Aidan Coffey
- Department of Biological Sciences, Cork Institute of Technology, Bishopstown, Cork, Ireland
| | - Elke K Arendt
- School of Food and Nutritional Sciences, University College Cork, Western Road, Cork, Ireland.
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19
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Meng X, Pijning T, Dobruchowska JM, Gerwig GJ, Dijkhuizen L. Characterization of the Functional Roles of Amino Acid Residues in Acceptor-binding Subsite +1 in the Active Site of the Glucansucrase GTF180 from Lactobacillus reuteri 180. J Biol Chem 2015; 290:30131-41. [PMID: 26507662 DOI: 10.1074/jbc.m115.687558] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Indexed: 11/06/2022] Open
Abstract
α-Glucans produced by glucansucrase enzymes hold strong potential for industrial applications. The exact determinants of the linkage specificity of glucansucrase enzymes have remained largely unknown, even with the recent elucidation of glucansucrase crystal structures. Guided by the crystal structure of glucansucrase GTF180-ΔN from Lactobacillus reuteri 180 in complex with the acceptor substrate maltose, we identified several residues (Asp-1028 and Asn-1029 from domain A, as well as Leu-938, Ala-978, and Leu-981 from domain B) near subsite +1 that may be critical for linkage specificity determination, and we investigated these by random site-directed mutagenesis. First, mutants of Ala-978 (to Leu, Pro, Phe, or Tyr) and Asp-1028 (to Tyr or Trp) with larger side chains showed reduced degrees of branching, likely due to the steric hindrance by these bulky residues. Second, Leu-938 mutants (except L938F) and Asp-1028 mutants showed altered linkage specificity, mostly with increased (α1 → 6) linkage synthesis. Third, mutation of Leu-981 and Asn-1029 significantly affected the transglycosylation reaction, indicating their essential roles in acceptor substrate binding. In conclusion, glucansucrase product specificity is determined by an interplay of domain A and B residues surrounding the acceptor substrate binding groove. Residues surrounding the +1 subsite thus are critical for activity and specificity of the GTF180 enzyme and play different roles in the enzyme functions. This study provides novel insights into the structure-function relationships of glucansucrase enzymes and clearly shows the potential of enzyme engineering to produce tailor-made α-glucans.
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Affiliation(s)
| | - Tjaard Pijning
- Biophysical Chemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
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20
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: an update for 2009-2010. MASS SPECTROMETRY REVIEWS 2015; 34:268-422. [PMID: 24863367 PMCID: PMC7168572 DOI: 10.1002/mas.21411] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 07/16/2013] [Accepted: 07/16/2013] [Indexed: 05/07/2023]
Abstract
This review is the sixth update of the original article published in 1999 on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2010. General aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, arrays and fragmentation are covered in the first part of the review and applications to various structural typed constitutes the remainder. The main groups of compound that are discussed in this section are oligo and polysaccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals. Many of these applications are presented in tabular form. Also discussed are medical and industrial applications of the technique, studies of enzyme reactions and applications to chemical synthesis.
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Affiliation(s)
- David J. Harvey
- Department of BiochemistryOxford Glycobiology InstituteUniversity of OxfordOxfordOX1 3QUUK
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21
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Meng X, Dobruchowska JM, Pijning T, Gerwig GJ, Kamerling JP, Dijkhuizen L. Truncation of domain V of the multidomain glucansucrase GTF180 of Lactobacillus reuteri 180 heavily impairs its polysaccharide-synthesizing ability. Appl Microbiol Biotechnol 2015; 99:5885-94. [PMID: 25586581 DOI: 10.1007/s00253-014-6361-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 12/17/2014] [Accepted: 12/20/2014] [Indexed: 01/23/2023]
Abstract
Glucansucrases are exclusively found in lactic acid bacteria and synthesize a variety of α-glucans from sucrose. They are large multidomain enzymes belonging to the CAZy family 70 of glycoside hydrolase enzymes (GH70). The crystal structure of the N-terminal truncated GTF180 of Lactobacillus reuteri 180 (GTF180-ΔN) revealed that the polypeptide chain follows a U shape course to form five domains, including domains A, B, and C, which resemble those of family GH13 enzymes, and two extra and novel domains (domains IV and V), which are attached to the catalytic core. To elucidate the functional roles of domain V, we have deleted the domain V fragments from both the N- and C-terminal ends (GTF180-ΔNΔV). Truncation of domain V of GTF180-ΔN yielded a catalytically fully active enzyme but with heavily impaired polysaccharide synthesis ability. Instead, GTF180-ΔNΔV produced a large amount of oligosaccharides. Domain V is not involved in determining the linkage specificity, and the size of polysaccharide produced as the polysaccharide produced by GTF180-ΔNΔV was identical in size and structure with that of GTF180-ΔN. The data indicates that GTF180-ΔNΔV acts nonprocessively, frequently initiating synthesis of a new oligosaccharide from sucrose, instead of continuing the synthesis of a full size polysaccharide. Mutations L940E and L940F in GTF180-ΔNΔV, which are involved in the acceptor substrate binding, restored polysaccharide synthesis almost to the level of GTF180-ΔN. These results demonstrated that interactions of growing glucan chains with both domain V and acceptor substrate binding sites are important for polysaccharide synthesis.
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Affiliation(s)
- Xiangfeng Meng
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, Nijenborgh 7, 9747, AG, Groningen, The Netherlands
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22
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Musa A, Miao M, Zhang T, Jiang B. Biotransformation of stevioside by Leuconostoc citreum SK24.002 alternansucrase acceptor reaction. Food Chem 2014; 146:23-9. [DOI: 10.1016/j.foodchem.2013.09.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2013] [Revised: 07/04/2013] [Accepted: 09/03/2013] [Indexed: 10/26/2022]
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23
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Leemhuis H, Pijning T, Dobruchowska JM, van Leeuwen SS, Kralj S, Dijkstra BW, Dijkhuizen L. Glucansucrases: three-dimensional structures, reactions, mechanism, α-glucan analysis and their implications in biotechnology and food applications. J Biotechnol 2012; 163:250-72. [PMID: 22796091 DOI: 10.1016/j.jbiotec.2012.06.037] [Citation(s) in RCA: 212] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 06/13/2012] [Accepted: 06/18/2012] [Indexed: 12/26/2022]
Abstract
Glucansucrases are extracellular enzymes that synthesize a wide variety of α-glucan polymers and oligosaccharides, such as dextran. These carbohydrates have found numerous applications in food and health industries, and can be used as pure compounds or even be produced in situ by generally regarded as safe (GRAS) lactic acid bacteria in food applications. Research in the recent years has resulted in big steps forward in the understanding and exploitation of the biocatalytic potential of glucansucrases. This paper provides an overview of glucansucrase enzymes, their recently elucidated crystal structures, their reaction and product specificity, and the structural analysis and applications of α-glucan polymers. Furthermore, we discuss key developments in the understanding of α-glucan polymer formation based on the recently elucidated three-dimensional structures of glucansucrase proteins. Finally we discuss the (potential) applications of α-glucans produced by lactic acid bacteria in food and health related industries.
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Affiliation(s)
- Hans Leemhuis
- Microbial Physiology, Groningen Biomolecular Sciences and Biotechnology Institute-GBB, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
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24
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Leemhuis H, Pijning T, Dobruchowska JM, Dijkstra BW, Dijkhuizen L. Glycosidic bond specificity of glucansucrases: on the role of acceptor substrate binding residues. BIOCATAL BIOTRANSFOR 2012. [DOI: 10.3109/10242422.2012.676301] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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25
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Patel S, Majumder A, Goyal A. Potentials of exopolysaccharides from lactic Acid bacteria. Indian J Microbiol 2012; 52:3-12. [PMID: 23449986 PMCID: PMC3298600 DOI: 10.1007/s12088-011-0148-8] [Citation(s) in RCA: 149] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Accepted: 11/04/2009] [Indexed: 10/18/2022] Open
Abstract
Recent research in the area of importance of microbes has revealed the immense industrial potential of exopolysaccharides and their derivative oligosaccharides from lactic acid bacteria. However, due to lack of adequate technological knowledge, the exopolysaccharides have remained largely under exploited. In the present review, the enormous potentials of different types of exopolysaccharides from lactic acid bacteria are described. This also summarizes the recent advances in the applications of exopolysaccharides, certain problems associated with their commercial production and the remedies.
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Affiliation(s)
- Seema Patel
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, 781 039 Assam India
| | - Avishek Majumder
- Department of System Biology, Technical University of Denmark, Building 224, DK-2800 Kgs., Lyngby, Denmark
| | - Arun Goyal
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, 781 039 Assam India
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26
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Hernandez-Hernandez O, Côté GL, Kolida S, Rastall RA, Sanz ML. In vitro fermentation of alternansucrase raffinose-derived oligosaccharides by human gut bacteria. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:10901-10906. [PMID: 21913653 DOI: 10.1021/jf202466s] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this work, in vitro fermentation of alternansucrase raffinose-derived oligosaccharides, previously fractionated according to their degree of polymerization (DP; from DP4 to DP10), was carried out using small-scale pH-controlled batch cultures at 37 °C under anaerobic conditions with human feces. Bifidogenic activity of oligosaccharides with DP4-6 similar to that of lactulose was observed; however, in general, a significant growth of lactic acid bacteria Bacteroides , Atopobium cluster, and Clostridium histolyticum group was not shown during incubation. Acetic acid was the main short chain fatty acid (SCFA) produced during the fermentation process; the highest levels of this acid were shown by alternansucrase raffinose acceptor pentasaccharides at 10 h (63.11 mM) and heptasaccharides at 24 h (54.71 mM). No significant differences between the gas volume produced by the mixture of raffinose-based oligosaccharides (DP5-DP10) and inulin after 24 h of incubation were detected, whereas lower gas volume was generated by DP4 oligosaccharides. These findings indicate that novel raffinose-derived oligosaccharides (DP4-DP10) could be a new source of prebiotic carbohydrates.
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27
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Hodoniczky J, Robinson GJ, McGraw EA, Rae AL. Fruit fly bioassay to distinguish "sweet" sugar structures. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:12885-12889. [PMID: 21077679 DOI: 10.1021/jf102458b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Palatable response to dietary sugars plays a significant role in influencing metabolic health. New structures are being explored with beneficial health properties, although consumer acceptance relies heavily on desirable sensory properties. Despite the importance of behavioral responses, the ability to elucidate structure-preference relationships of sugars is lacking. A wild population of Drosophila melanogaster was used as a model to perform pairwise comparisons across structural groups to characterize a fruit fly bioassay for assessing sugar preference. Preference was successfully described in structurally relevant terms, particularly through the ability to directly test sugars of related structures in addition to standard sucrose comparisons. The fruit fly bioassay also provided the first report on the relative preference for the β-linked sugar alcohol, gentiobiitol. In making reference to well-known human preferences, the bioassay also raises opportunities for greater understanding of behavioral response to sugar structures in general.
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Affiliation(s)
- Jason Hodoniczky
- CSIRO Plant Industry, 306 Carmody Road, St. Lucia, Queensland 4067, Australia
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28
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Patel S, Goyal A. Functional oligosaccharides: production, properties and applications. World J Microbiol Biotechnol 2010. [DOI: 10.1007/s11274-010-0558-5] [Citation(s) in RCA: 185] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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29
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Transglucosidases as efficient tools for oligosaccharide and glucoconjugate synthesis. Curr Opin Microbiol 2010; 13:293-300. [DOI: 10.1016/j.mib.2010.03.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 03/08/2010] [Accepted: 03/09/2010] [Indexed: 11/18/2022]
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30
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André I, Potocki-Véronèse G, Morel S, Monsan P, Remaud-Siméon M. Sucrose-Utilizing Transglucosidases for Biocatalysis. Top Curr Chem (Cham) 2010; 294:25-48. [DOI: 10.1007/128_2010_52] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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31
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Synthesis of dextrans with controlled amounts of α-1,2 linkages using the transglucosidase GBD–CD2. Appl Microbiol Biotechnol 2009; 86:545-54. [DOI: 10.1007/s00253-009-2241-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2009] [Revised: 07/31/2009] [Accepted: 09/02/2009] [Indexed: 10/20/2022]
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32
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Côté GL, Dunlap CA, Vermillion KE. Glucosylation of raffinose via alternansucrase acceptor reactions. Carbohydr Res 2009; 344:1951-9. [PMID: 19596226 DOI: 10.1016/j.carres.2009.06.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2009] [Revised: 06/02/2009] [Accepted: 06/22/2009] [Indexed: 10/20/2022]
Abstract
The glucansucrase known as alternansucrase [EC 2.4.1.140] can transfer glucosyl units from sucrose to raffinose to give good yields of oligosaccharides, which may serve as prebiotics. The main products were the tetrasaccharides alpha-d-Glcp-(1-->3)-alpha-d-Galp-(1-->6)-alpha-d-Glcp-(1<-->2)-beta-d-Fruf and alpha-d-Glcp-(1-->4)-alpha-d-Galp-(1-->6)-alpha-d-Glcp-(1<-->2)-beta-d-Fruf in ratios ranging from 4:1 to 9:1, along with lesser amounts of alpha-d-Glcp-(1-->6)-alpha-d-Galp-(1-->6)-alpha-d-Glcp-(1<-->2)-beta-d-Fruf. Ten unusual pentasaccharide structures were isolated. Three of these arose from glucosylation of the major tetrasaccharide product, two each from the minor tetrasaccharides, and three were the result of glucosylations of the fructose acceptor product leucrose or isomaltulose. The major pentasaccharide product arose from glucosylation of the major tetrasaccharide at position 4 of the fructofuranosyl unit, to give a subunit structure analogous to that of maltulose. A number of hexasaccharides and higher oligosaccharides were also produced. Unlike alternansucrase, dextransucrase [EC 2.4.1.5] gave only a single tetrasaccharide product in low yield, and no significant amounts of higher oligosaccharides. The tetrasaccharide structure from dextransucrase was found to be alpha-d-Glcp-(1-->4)-alpha-d-Galp-(1-->6)-alpha-d-Glcp-(1<-->2)-beta-d-Fruf, which is at odds with the previously published structure.
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Affiliation(s)
- Gregory L Côté
- National Center for Agricultural Utilization Research, United States Department of Agriculture, Peoria, IL 61604, USA.
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