1
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Wong Min M, Liu L, Karboune S. Investigating the Potential of Phenolic Compounds and Carbohydrates as Acceptor Substrates for Levansucrase-Catalyzed Transfructosylation Reaction. Chembiochem 2024; 25:e202400107. [PMID: 38536122 DOI: 10.1002/cbic.202400107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/24/2024] [Indexed: 05/03/2024]
Abstract
This study characterizes the acceptor specificity of levansucrases (LSs) from Gluconobacter oxydans (LS1), Vibrio natriegens (LS2), Novosphingobium aromaticivorans (LS3), and Paraburkholderia graminis (LS4) using sucrose as fructosyl donor and selected phenolic compounds and carbohydrates as acceptors. Overall, V. natriegens LS2 proved to be the best biocatalyst for the transfructosylation of phenolic compounds. More than one fructosyl unit could be attached to fructosylated phenolic compounds. The transfructosylation of epicatechin by P. graminis LS4 resulted in the most diversified products, with up to five fructosyl units transferred. In addition to the LS source, the acceptor specificity of LS towards phenolic compounds and their transfructosylation products were found to greatly depend on their chemical structure: the number of phenolic rings, the reactivity of hydroxyl groups and the presence of aliphatic chains or methoxy groups. Similarly, for carbohydrates, the transfructosylation yield was dependent on both the LS source and the acceptor type. The highest yield of fructosylated-trisaccharides was Erlose from the transfructosylation of maltose catalyzed by LS2, with production reaching 200 g/L. LS2 was more selective towards the transfructosylation of phenolic compounds and carbohydrates, while reactions catalyzed by LS1, LS3 and LS4 also produced fructooligosaccharides. This study shows the high potential for the application of LSs in the glycosylation of phenolic compounds and carbohydrates.
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Affiliation(s)
- Muriel Wong Min
- Department of Food Science & Agricultural Chemistry, McGill University, 21111, Lakeshore, Ste-Anne-de-Bellevue, Quebec, Canada
| | - Lan Liu
- Department of Food Science & Agricultural Chemistry, McGill University, 21111, Lakeshore, Ste-Anne-de-Bellevue, Quebec, Canada
| | - Salwa Karboune
- Department of Food Science & Agricultural Chemistry, McGill University, 21111, Lakeshore, Ste-Anne-de-Bellevue, Quebec, Canada
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2
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Xu W, Zhang X, Ni D, Zhang W, Guang C, Mu W. A review of fructosyl-transferases from catalytic characteristics and structural features to reaction mechanisms and product specificity. Food Chem 2024; 440:138250. [PMID: 38154282 DOI: 10.1016/j.foodchem.2023.138250] [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: 09/28/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 12/30/2023]
Abstract
Carbohydrate-active enzymes are accountable for the synthesis and degradation of glycosidic bonds among diverse carbohydrates. Fructosyl-transferases represent a subclass of these enzymes, employing sucrose as a substrate to generate fructooligosaccharides (FOS) and fructan polymers. This category primarily includes levansucrase (LS, EC 2.4.1.10), inulosucrase (IS, EC 2.4.1.9), and β-fructofuranosidase (Ffase, EC 3.2.1.26). These three enzymes possess a similar five-bladed β-propeller fold and employ an anomer-retaining reaction mechanism mediated by nucleophiles, transition state stabilizers, and general acids/bases. However, they exhibit distinct product profiles, characterized by variations in linkage specificity and molecular mass distribution. Consequently, this article comprehensively explores recent advancements in the catalytic characteristics, structural features, reaction mechanisms, and product specificity of levansucrase, inulosucrase, and β-fructofuranosidase (abbreviated as LS, IS, and Ffase, respectively). Furthermore, it discusses the potential for modifying catalytic properties and product specificity through structure-based design, which enables the rational production of custom fructan and FOS.
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Affiliation(s)
- Wei Xu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Xiaoqi Zhang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Dawei Ni
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Cuie Guang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China.
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3
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Klaewkla M, Wangpaiboon K, Pichyangkura R, Charoenwongpaiboon T. Unraveling the role of flexible coil near calcium binding site of levansucrase on thermostability and product profile via proline substitution and molecular dynamics simulations. Proteins 2024; 92:170-178. [PMID: 37753539 DOI: 10.1002/prot.26592] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 08/18/2023] [Accepted: 09/07/2023] [Indexed: 09/28/2023]
Abstract
Due to its bioactivity and versatile applications, levan has appeared as a promising biomaterial. Levansucrase is responsible for the conversion of sucrose into levan. With the goal of enhancing levan production, the strategy for enhancing the stability of levansucrase is being intensively studied. To make proteins more stable under high temperatures, proline, the most rigid residue, can be introduced into previously flexible regions. Herein, G249, D250, N251, and H252 on the flexible coil close to the calcium binding site of Bacillus licheniformis levansucrase were replaced with proline. Mutations at G249P greatly enhance both the enzyme's thermodynamic and kinetic stability, while those at H252P improve solely the enzyme's kinetic stability. GPC analysis revealed that G249P synthesize more levan, but H252P generate primarily oligosaccharides. Molecular dynamics simulations (MD) and MM/GBSA analysis revealed that G249P mutation increased not only the stability of levansucrase, but also affinity toward fructan.
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Affiliation(s)
| | - Karan Wangpaiboon
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Rath Pichyangkura
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
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Albani S, Polsinelli I, Mazzei L, Musiani F, Benini S. Determination and Kinetic Characterization of a New Potential Inhibitor for AmsI Protein Tyrosine Phosphatase from the Apple Pathogen Erwinia amylovora. Molecules 2023; 28:7774. [PMID: 38067503 PMCID: PMC10708540 DOI: 10.3390/molecules28237774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 11/21/2023] [Accepted: 11/23/2023] [Indexed: 12/18/2023] Open
Abstract
Erwinia amylovora is a Gram-negative bacterium, responsible for the fire blight disease in Rosaceae plants. Its virulence is correlated with the production of an exopolysaccharide (EPS) called amylovoran, which protects the bacterium from the surrounding environment and helps its diffusion inside the host. Amylovoran biosynthesis relies on the expression of twelve genes clustered in the ams operon. One of these genes, amsI, encodes for a Low Molecular Weight Protein Tyrosine Phosphatase (LMW-PTP) called EaAmsI, which plays a key role in the regulation of the EPS production pathway. For this reason, EaAmsI was chosen in this work as a target for the development of new antibacterial agents against E. amylovora. To achieve this aim, a set of programs (DOCK6, OpenEye FRED) was selected to perform a virtual screening using a database of ca. 700 molecules. The six best-scoring compounds identified were tested in in vitro assays. A complete inhibition kinetic characterization carried out on the most promising molecule (n-Heptyl β-D-glucopyranoside, N7G) showed an inhibition constant of 7.8 ± 0.6 µM. This study represents an initial step towards the development of new EaAmsI inhibitors able to act as antibacterial agents against E. amylovora infections.
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Affiliation(s)
- Simone Albani
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy; (S.A.); (L.M.)
| | - Ivan Polsinelli
- Bioorganic Chemistry and Bio-Crystallography Laboratory (B2Cl), Faculty of Agricultural, Environmental and Food Sciences, Free University of Bolzano, 39100 Bolzano, Italy;
- Institute of Molecular and Translational Cardiology (IMTC), IRCCS Policlinico San Donato, 20097 San Donato Milanese, Italy
| | - Luca Mazzei
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy; (S.A.); (L.M.)
| | - Francesco Musiani
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy; (S.A.); (L.M.)
| | - Stefano Benini
- Bioorganic Chemistry and Bio-Crystallography Laboratory (B2Cl), Faculty of Agricultural, Environmental and Food Sciences, Free University of Bolzano, 39100 Bolzano, Italy;
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Identification of a Thermostable Levansucrase from Pseudomonas orientalis That Allows Unique Product Specificity at Different Temperatures. Polymers (Basel) 2023; 15:polym15061435. [PMID: 36987215 PMCID: PMC10058814 DOI: 10.3390/polym15061435] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 03/09/2023] [Accepted: 03/09/2023] [Indexed: 03/17/2023] Open
Abstract
The biological production of levan by levansucrase (LS, EC 2.4.1.10) has aroused great interest in the past few years. Previously, we identified a thermostable levansucrase from Celerinatantimonas diazotrophica (Cedi-LS). A novel thermostable LS from Pseudomonas orientalis (Psor-LS) was successfully screened using the Cedi-LS template. The Psor-LS showed maximum activity at 65 °C, much higher than the other LSs. However, these two thermostable LSs showed significantly different product specificity. When the temperature was decreased from 65 to 35 °C, Cedi-LS tended to produce high-molecular-weight (HMW) levan. By contrast, Psor-LS prefers to generate fructooligosaccharides (FOSs, DP ≤ 16) rather than HMW levan under the same conditions. Notably, at 65 °C, Psor-LS would produce HMW levan with an average Mw of 1.4 × 106 Da, indicating that a high temperature might favor the accumulation of HMW levan. In summary, this study allows a thermostable LS suitable for HMW levan and levan-type FOSs production simultaneously.
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Zhang X, Xu W, Ni D, Zhang W, Guang C, Mu W. Successful Manipulation of the Product Spectrum of the Erwinia amylovora Levansucrase by Modifying the Residues around loop1, Loop 3, and Loop 4. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:680-689. [PMID: 36538710 DOI: 10.1021/acs.jafc.2c07891] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Levansucrase (LS, EC 2.4.1.10) catalyzes the synthesis of levan by successively transferring the fructosyl moiety from sucrose to an elongated fructan chain. Although the product distribution of LS from Erwinia amylovora (Ea-LS) was studied under different sucrose concentrations, the effect of residues on the product formation is yet unknown. The first levanhexaose-complexed structure of LS from Bacillus subtilis (Bs-SacB) provided information on the oligosaccharide binding sites (OB sites), from +1 to +4 subsites. Since Ea-LS would efficiently produce fructooligosaccharides, a substitution mutation of OB sites in Bs-SacB and the corresponding residues of Ea-LS were conducted to investigate how these mutants would influence the product distribution. As a result, a series of mutants with different product spectrum were obtained. Notably, the mutants of G98E, V151F, and N200T around loop 1, loop 3, and loop 4 all showed a significant increase in both the molecular mass and the yield of high-molecular-mass levan, suggesting that the product profile of Ea-LS was significantly modified.
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Affiliation(s)
- Xiaoqi Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Wei Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Dawei Ni
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Cuie Guang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, Jiangsu, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China
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7
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Ko H, Sung BH, Kim MJ, Sohn JH, Bae JH. Fructan Biosynthesis by Yeast Cell Factories. J Microbiol Biotechnol 2022; 32:1373-1381. [PMID: 36310357 PMCID: PMC9720074 DOI: 10.4014/jmb.2207.07062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/31/2022] [Accepted: 08/31/2022] [Indexed: 11/29/2022]
Abstract
Fructan is a polysaccharide composed of fructose and can be classified into several types, such as inulin, levan, and fructo-oligosaccharides, based on their linkage patterns and degree of polymerization. Owing to its structural and functional diversity, fructan has been used in various fields including prebiotics, foods and beverages, cosmetics, and pharmaceutical applications. With increasing interest in fructans, efficient and straightforward production methods have been explored. Since the 1990s, yeast cells have been employed as producers of recombinant enzymes for enzymatic conversion of fructans including fructosyltransferases derived from various microbes and plants. More recently, yeast cell factories are highlighted as efficient workhorses for fructan production by direct fermentation. In this review, recent advances and strategies for fructan biosynthesis by yeast cell factories are discussed.
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Affiliation(s)
- Hyunjun Ko
- Synthetic Biology & Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
| | - Bong Hyun Sung
- Synthetic Biology & Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
| | - Mi-Jin Kim
- Synthetic Biology & Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
| | - Jung-Hoon Sohn
- Synthetic Biology & Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea,Cellapy Bio Inc., Bio-Venture Center 211, Daejeon 34141, Republic of Korea,Corresponding authors J.H. Sohn Phone: +82-42-860-4458 Fax: +82-42-860-4489 E-mail:
| | - Jung-Hoon Bae
- Synthetic Biology & Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea,
J.H. Bae Phone: +82-42-860-4484 Fax: +82-42-860-4489 E-mail:
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8
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Levan-type fructooligosaccharides synthesis by novel levansucrase-inulosucrase fusion enzyme. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2022.108524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Anguluri K, La China S, Brugnoli M, De Vero L, Pulvirenti A, Cassanelli S, Gullo M. Candidate Acetic Acid Bacteria Strains for Levan Production. Polymers (Basel) 2022; 14:polym14102000. [PMID: 35631879 PMCID: PMC9146431 DOI: 10.3390/polym14102000] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/06/2022] [Accepted: 05/11/2022] [Indexed: 01/27/2023] Open
Abstract
In this study, twelve strains of acetic acid bacteria (AAB) belonging to five different genera were tested for their ability to produce levan, at 70 and 250 g/L of sucrose concentration, respectively. The fructan produced by the bacterial strains was characterized as levan by NMR spectroscopy. Most of the strains produced levan, highlighting intra- and inter-species variability. High yield was observed for Neoasaia chiangmaiensis NBRC 101099 T, Kozakia baliensis DSM 14400 T and Gluconobacter cerinus DSM 9533 T at 70 g/L of sucrose. A 12-fold increase was observed for N. chiangmaiensis NBRC 101099 T at 250 g/L of sucrose concentration. Levan production was found to be affected by glucose accumulation and pH reduction, especially in Ko. baliensis DSM 14400 T. All the Gluconobacter strains showed a negative correlation with the increase in sucrose concentration. Among strains of Komagataeibacter genus, no clear effect of sucrose on levan yield was found. Results obtained in this study highlighted the differences in levan yield among AAB strains and showed interdependence between culture conditions, carbon source utilization, and time of incubation. On the contrary, the levan yield was not always related to the sucrose concentration.
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10
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Xu W, Ni D, Hou X, Pijning T, Guskov A, Rao Y, Mu W. Crystal Structure of Levansucrase from the Gram-Negative Bacterium Brenneria Provides Insights into Its Product Size Specificity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:5095-5105. [PMID: 35388691 DOI: 10.1021/acs.jafc.2c01225] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Microbial levansucrases (LSs, EC 2.4.1.10) have been widely studied for the synthesis of β-(2,6)-fructans (levan) from sucrose. LSs synthesize levan-type fructo-oligosaccharides, high-molecular-mass levan polymer or combinations of both. Here, we report crystal structures of LS from the G--bacterium Brenneria sp. EniD 312 (Brs-LS) in its apo form, as well as of two mutants (A154S, H327A) targeting positions known to affect LS reaction specificity. In addition, we report a structure of Brs-LS complexed with sucrose, the first crystal structure of a G--LS with a bound substrate. The overall structure of Brs-LS is similar to that of G-- and G+-LSs, with the nucleophile (D68), transition stabilizer (D225), and a general acid/base (E309) in its active site. The H327A mutant lacks an essential interaction with glucosyl moieties of bound substrates in subsite +1, explaining the observed smaller products synthesized by this mutant. The A154S mutation affects the hydrogen-bond network around the transition stabilizing residue (D225) and the nucleophile (D68), and may affect the affinity of the enzyme for sucrose such that it becomes less effective in transfructosylation. Taken together, this study provides novel insights into the roles of structural elements and residues in the product specificity of LSs.
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Affiliation(s)
- Wei Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China
| | - Dawei Ni
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China
| | - Xiaodong Hou
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
| | - Tjaard Pijning
- Biomolecular X-ray Crystallography, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Albert Guskov
- Biomolecular X-ray Crystallography, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | - Yijian Rao
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, PR China
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11
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Wangpaiboon K, Klaewkla M, Charoenwongpaiboon T, Vongkusolkit N, Panpetch P, Kuttiyawong K, Visessanguan W, Pichyangkura R. Synergistic enzyme cocktail between levansucrase and inulosucrase for superb levan-type fructooligosaccharide synthesis. Enzyme Microb Technol 2021; 154:109960. [PMID: 34923315 DOI: 10.1016/j.enzmictec.2021.109960] [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: 09/15/2021] [Revised: 10/17/2021] [Accepted: 12/04/2021] [Indexed: 11/24/2022]
Abstract
Inulosucrase (ISC) and levansucrase (LSC) utilise sucrose and produce inulin- and levan-type fructans, respectively. This study aims to propose a new strategy to improve levan-type fructooligosaccharide (L-FOS) production. The effect of ISC/ LSC -mixed reaction was elucidated on L-FOS production. The presence of ISC in the LSC reaction significantly leads to the higher production of L-FOSs as the main products. Furthermore, the different ratios between ISC and LSC affected the distribution of L-FOSs. A greater amount of ISC compared to LSC promoted the synthesis of short-chain L-FOSs. Conversely, when LSC was increased, the synthesis of longer-chain L-FOSs was enhanced. The addition of trisaccharide mixtures obtained from either a single ISC or LSC reaction could enhance L-FOSs synthesis in the LSC reaction. Analysis of these trisaccharides revealed that most species of the oligosaccharides were similar, with 1-kestose being the major one. The supplement of only 1-kestose in the LSC reaction showed similar results to those of the reaction in the presence of trisaccharide mixtures. Moreover, the results were supported by molecular dynamics simulations. This work not only provides an improvement in L-FOS production but also revealed and supported some insights into the mechanism of fructansucrases.
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Affiliation(s)
- Karan Wangpaiboon
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Methus Klaewkla
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | | | - Napas Vongkusolkit
- Department of Biology, Barnard College, Columbia University, New York, NY 10027, USA
| | - Pawinee Panpetch
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Kamontip Kuttiyawong
- Department of Chemistry, Faculty of Liberal Arts and Science, Kasetsart University Kamphaeng Saen Campus, Nakhon Pathom 73140, Thailand
| | - Wonnop Visessanguan
- National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Paholayothin Road, Klong 1, Klong Luang, Pathumthani 12120, Thailand
| | - Rath Pichyangkura
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
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12
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Okuyama M, Serizawa R, Tanuma M, Kikuchi A, Sadahiro J, Tagami T, Lang W, Kimura A. Molecular insight into regioselectivity of transfructosylation catalyzed by GH68 levansucrase and β-fructofuranosidase. J Biol Chem 2021; 296:100398. [PMID: 33571525 PMCID: PMC7961098 DOI: 10.1016/j.jbc.2021.100398] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 02/02/2021] [Accepted: 02/04/2021] [Indexed: 01/22/2023] Open
Abstract
Glycoside hydrolase family 68 (GH68) enzymes catalyze β-fructosyltransfer from sucrose to another sucrose, the so-called transfructosylation. Although regioselectivity of transfructosylation is divergent in GH68 enzymes, there is insufficient information available on the structural factor(s) involved in the selectivity. Here, we found two GH68 enzymes, β-fructofuranosidase (FFZm) and levansucrase (LSZm), encoded tandemly in the genome of Zymomonas mobilis, displayed different selectivity: FFZm catalyzed the β-(2→1)-transfructosylation (1-TF), whereas LSZm did both of 1-TF and β-(2→6)-transfructosylation (6-TF). We identified His79FFZm and Ala343FFZm and their corresponding Asn84LSZm and Ser345LSZm respectively as the structural factors for those regioselectivities. LSZm with the respective substitution of FFZm-type His and Ala for its Asn84LSZm and Ser345LSZm (N84H/S345A-LSZm) lost 6-TF and enhanced 1-TF. Conversely, the LSZm-type replacement of His79FFZm and Ala343FFZm in FFZm (H79N/A343S-FFZm) almost lost 1-TF and acquired 6-TF. H79N/A343S-FFZm exhibited the selectivity like LSZm but did not produce the β-(2→6)-fructoside-linked levan and/or long levanooligosaccharides that LSZm did. We assumed Phe189LSZm to be a responsible residue for the elongation of levan chain in LSZm and mutated the corresponding Leu187FFZm in FFZm to Phe. An H79N/L187F/A343S-FFZm produced a higher quantity of long levanooligosaccharides than H79N/A343S-FFZm (or H79N-FFZm), although without levan formation, suggesting that LSZm has another structural factor for levan production. We also found that FFZm generated a sucrose analog, β-D-fructofuranosyl α-D-mannopyranoside, by β-fructosyltransfer to d-mannose and regarded His79FFZm and Ala343FFZm as key residues for this acceptor specificity. In summary, this study provides insight into the structural factors of regioselectivity and acceptor specificity in transfructosylation of GH68 enzymes.
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Affiliation(s)
- Masayuki Okuyama
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan.
| | - Ryo Serizawa
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Masanari Tanuma
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Asako Kikuchi
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Juri Sadahiro
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Takayoshi Tagami
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Weeranuch Lang
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Atsuo Kimura
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan.
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Tonozuka T, Kitamura J, Nagaya M, Kawai R, Nishikawa A, Hirano K, Tamura K, Fujii T, Tochio T. Crystal structure of a glycoside hydrolase family 68 β-fructosyltransferase from Beijerinckia indica subsp. indica in complex with fructose. Biosci Biotechnol Biochem 2020; 84:2508-2520. [DOI: 10.1080/09168451.2020.1804317] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Abstract
An enzyme belonging to glycoside hydrolase family 68 (GH68) from Beijerinckia indica subsp. indica NBRC 3744 was expressed in Escherichia coli. Biochemical characterization showed that the enzyme was identified to be a β-fructosyltransferase (BiBftA). Crystallization of a full-length BiBftA was initially attempted, but no crystals were obtained. We constructed a variant in which 5 residues (Pro199-Gly203) and 13 residues (Leu522-Gln534) in potentially flexible regions were deleted, and we successfully crystallized this variant BiBftA. BiBftA is composed of a five-bladed β-propeller fold as in other GH68 enzymes. The structure of BiBftA in complex with fructose unexpectedly indicated that one β-fructofuranose (β-Fruf) molecule and one β-fructopyranose molecule bind to the catalytic pocket. The orientation of β-Fruf at subsite −1 is tilted from the orientation observed in most GH68 enzymes, presenting a second structure of a GH68 enzyme in complex with the tilted binding mode of β-Fruf.
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Affiliation(s)
- Takashi Tonozuka
- Department of Applied Biological Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Junichi Kitamura
- Department of Applied Biological Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Mika Nagaya
- Department of Applied Biological Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Reika Kawai
- Department of Applied Biological Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Atsushi Nishikawa
- Department of Applied Biological Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
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Implications of the mutation S164A on Bacillus subtilis levansucrase product specificity and insights into protein interactions acting upon levan synthesis. Int J Biol Macromol 2020; 161:898-908. [PMID: 32553967 DOI: 10.1016/j.ijbiomac.2020.06.114] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/10/2020] [Accepted: 06/11/2020] [Indexed: 12/20/2022]
Abstract
Mutation S164A largely affects the transfructosylation properties of Bacillus subtilis levansucrase (SacB). The variant uses acceptors such as glucose and short levans with an average molecular weight of 7.6 kDa more efficiently than SacB, leading to the enhanced synthesis of medium and high molecular weight polymer and a blasto-oligosaccharide series with a polymerization degree of 2-10. A 3-fold increase in blasto-oligosaccharides yield is provoked by the modified interplay between the variant and glucose. Despite its modified product specificity, protein-carbohydrate and protein-protein interactions are still a major factor affecting size and distribution of levan molecular weight. This study highlights the importance of critical factors such as protein concentration in the analysis of wild-type and mutagenized levansucrases. Docking experiments with the crystal structures of SacB and variant S164A - the latter obtained at a 2.6 Å resolution - identified unreported potential binding subsites for fructosyl moieties on the surface of both enzymes.
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15
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The Structure of Sucrose-Soaked Levansucrase Crystals from Erwinia tasmaniensis reveals a Binding Pocket for Levanbiose. Int J Mol Sci 2019; 21:ijms21010083. [PMID: 31877648 PMCID: PMC6981717 DOI: 10.3390/ijms21010083] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/13/2019] [Accepted: 12/17/2019] [Indexed: 12/17/2022] Open
Abstract
Given its potential role in the synthesis of novel prebiotics and applications in the pharmaceutical industry, a strong interest has developed in the enzyme levansucrase (LSC, EC 2.4.1.10). LSC catalyzes both the hydrolysis of sucrose (or sucroselike substrates) and the transfructosylation of a wide range of acceptors. LSC from the Gram-negative bacterium Erwinia tasmaniensis (EtLSC) is an interesting biocatalyst due to its high-yield production of fructooligosaccharides (FOSs). In order to learn more about the process of chain elongation, we obtained the crystal structure of EtLSC in complex with levanbiose (LBS). LBS is an FOS intermediate formed during the synthesis of longer-chain FOSs and levan. Analysis of the LBS binding pocket revealed that its structure was conserved in several related species. The binding pocket discovered in this crystal structure is an ideal target for future mutagenesis studies in order to understand its biological relevance and to engineer LSCs into tailored products.
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16
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Engineered thermostable β–fructosidase from Thermotoga maritima with enhanced fructooligosaccharides synthesis. Enzyme Microb Technol 2019; 125:53-62. [DOI: 10.1016/j.enzmictec.2019.02.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 12/13/2018] [Accepted: 02/05/2019] [Indexed: 11/23/2022]
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17
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Polsinelli I, Caliandro R, Salomone-Stagni M, Demitri N, Rejzek M, Field RA, Benini S. Comparison of the Levansucrase from the epiphyte Erwinia tasmaniensis vs its homologue from the phytopathogen Erwinia amylovora. Int J Biol Macromol 2019; 127:496-501. [PMID: 30660564 DOI: 10.1016/j.ijbiomac.2019.01.074] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/16/2019] [Accepted: 01/16/2019] [Indexed: 11/27/2022]
Abstract
Erwinia tasmaniensis is an epiphytic bacterium related to the plant pathogen Erwinia amylovora, the etiological agent of fire blight. In this study the levansucrase from E. tasmaniensis (EtLsc) has been compared with the homologous enzyme from E. amylovora (EaLsc). We characterized the enzymatic activity and compared the products profile of both enzymes by High Performance Anion Exchange Chromatography coupled with Pulsed Amperometric Detector (HPAEC-PAD). Moreover we determined the crystal structure of EtLsc to understand the structural peculiarity causing the different product profiles of the two homologues. EtLsc exhibits increased efficiency in the production of FOS, resulting in a better catalyst for biotechnological synthesis than EaLsc. Based on our results, we propose that the role of this enzyme in the life cycle of the two bacteria is most likely related to survival, rather than linked to pathogenicity in E. amylovora.
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Affiliation(s)
- Ivan Polsinelli
- Bioorganic Chemistry and Bio-Crystallography laboratory (B(2)Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, 39100 Bolzano, Italy
| | - Rosanna Caliandro
- Bioorganic Chemistry and Bio-Crystallography laboratory (B(2)Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, 39100 Bolzano, Italy
| | - Marco Salomone-Stagni
- Bioorganic Chemistry and Bio-Crystallography laboratory (B(2)Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, 39100 Bolzano, Italy
| | - Nicola Demitri
- Elettra-Sincrotrone Trieste, S.S. 14 Km 163.5 in Area Science Park, Basovizza, Trieste 34149, Italy
| | - Martin Rejzek
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich, NR47UH, United Kingdom
| | - Robert A Field
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich, NR47UH, United Kingdom
| | - Stefano Benini
- Bioorganic Chemistry and Bio-Crystallography laboratory (B(2)Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, 39100 Bolzano, Italy.
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18
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Hill A, Chen L, Mariage A, Petit JL, de Berardinis V, Karboune S. Discovery of new levansucrase enzymes with interesting properties and improved catalytic activity to produce levan and fructooligosaccharides. Catal Sci Technol 2019. [DOI: 10.1039/c9cy00135b] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mining for new levansucrase enzymes with high levan production, transfructosylating activity, and thermal stability and studying their kinetics and acceptor specificity.
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Affiliation(s)
- Andrea Hill
- Department of Food Science
- McGill University
- Quebec
- H9X 3V9 Canada
| | - Lily Chen
- Department of Food Science
- McGill University
- Quebec
- H9X 3V9 Canada
| | - Aline Mariage
- Génomique Métabolique, Genoscope
- Institut François Jacob
- CEA
- CNRS
- Univ Evry
| | - Jean-Louis Petit
- Génomique Métabolique, Genoscope
- Institut François Jacob
- CEA
- CNRS
- Univ Evry
| | | | - Salwa Karboune
- Department of Food Science
- McGill University
- Quebec
- H9X 3V9 Canada
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19
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Xu W, Ni D, Zhang W, Guang C, Zhang T, Mu W. Recent advances in Levansucrase and Inulosucrase: evolution, characteristics, and application. Crit Rev Food Sci Nutr 2018; 59:3630-3647. [DOI: 10.1080/10408398.2018.1506421] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Wei Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Dawei Ni
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, China
| | - Wenli Zhang
- 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
| | - Tao Zhang
- 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
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20
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Charoenwongpaiboon T, Sitthiyotha T, Na Ayutthaya PP, Wangpaiboon K, Chunsrivirot S, Hengsakul Prousoontorn M, Pichyangkura R. Modulation of fructooligosaccharide chain length and insight into the product binding motif of Lactobacillus reuteri 121 inulosucrase. Carbohydr Polym 2018; 209:111-121. [PMID: 30732790 DOI: 10.1016/j.carbpol.2018.12.078] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 12/18/2018] [Accepted: 12/23/2018] [Indexed: 12/18/2022]
Abstract
Inulosucrase (E.C. 2.4.1.9) is a bacterial fructosyltransferase that synthesizes inulin-type fructooligosaccharide, using sucrose as a substrate. We modulated the size of fructooligosaccharide synthesized by Lactobacillus reuteri 121 inulosucrase using rational designed mutagenesis. Nine residues: D478, D479, S482, R483, N543, W551, N555, N561 and D689, were changed based on the active site architecture and amino acids potentially interacting with saccharides. The selected residues were substituted with alanine to investigate the contribution of these residues to FOS chain length. Enzymatic activity assays demonstrated that the transglycosylation/hydrolysis ratios of D479A, R483A, N543A, W551A and N555A mutants were significantly different from that of the wild type. Almost all mutants, except D478A, synthesized oligosaccharides with different size distribution compared to that of wild type. Molecular docking further provides insights into the product binding motif of Lactobacillus reuteri 121 inulosucrase and strengthens an important role of amino acid residues at remote locations from the active site on the enzymatic activity and product specificity.
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Affiliation(s)
- Thanapon Charoenwongpaiboon
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand.
| | - Thassanai Sitthiyotha
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand; Structural and Computational Biology Research Unit, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand.
| | | | - Karan Wangpaiboon
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand.
| | - Surasak Chunsrivirot
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand; 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, Pathumwan, Bangkok 10330, Thailand.
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21
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Rodrigo-Frutos D, Piedrabuena D, Sanz-Aparicio J, Fernández-Lobato M. Yeast cultures expressing the Ffase from Schwanniomyces occidentalis, a simple system to produce the potential prebiotic sugar 6-kestose. Appl Microbiol Biotechnol 2018; 103:279-289. [DOI: 10.1007/s00253-018-9446-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 10/02/2018] [Accepted: 10/09/2018] [Indexed: 12/30/2022]
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22
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Peng J, Xu W, Ni D, Zhang W, Zhang T, Guang C, Mu W. Preparation of a novel water-soluble gel from Erwinia amylovora levan. Int J Biol Macromol 2018; 122:469-478. [PMID: 30342147 DOI: 10.1016/j.ijbiomac.2018.10.093] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 10/01/2018] [Accepted: 10/14/2018] [Indexed: 02/04/2023]
Abstract
Less attention has been focused on the industrial applications of levan-type fructan than that of inulin. Levan-type fructan is a unique homopolysaccharide consisting of fructose residues with a β-(2, 6) linkage that possesses unique physiochemical properties such as low intrinsic viscosity. In this study, the recombinant levansucrase from Erwinia amylovora was used to efficiently produce levan from sucrose, and under optimised conditions, 195 g/L levan was produced from 500 g/L sucrose, with the highest conversion rate of 59%. The physicochemical properties of E. amylovora levan, such as surface morphology, thermal behaviour, rheology behaviour and texture analysis, were evaluated and compared with those of commercial gels, including xanthan, guar, carrageenan and Arabic gums. The produced E. amylovora levan showed a series of acceptable physicochemical properties, indicating a potential application for levan as a novel water-soluble micro gel. The conclusions of this study support the exploration of the use of more hydrogels in the food, medicinal and cosmetic industries.
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Affiliation(s)
- Jiaying Peng
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wei Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Dawei Ni
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Technology, 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 214122, China
| | - Cuie Guang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi 214122, China.
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23
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Kirtel O, Menéndez C, Versluys M, Van den Ende W, Hernández L, Toksoy Öner E. Levansucrase from Halomonas smyrnensis AAD6T: first halophilic GH-J clan enzyme recombinantly expressed, purified, and characterized. Appl Microbiol Biotechnol 2018; 102:9207-9220. [DOI: 10.1007/s00253-018-9311-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 08/03/2018] [Accepted: 08/06/2018] [Indexed: 12/21/2022]
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24
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2013-2014. MASS SPECTROMETRY REVIEWS 2018; 37:353-491. [PMID: 29687922 DOI: 10.1002/mas.21530] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 11/29/2016] [Indexed: 06/08/2023]
Abstract
This review is the eighth update of the original article published in 1999 on the application of Matrix-assisted laser desorption/ionization mass spectrometry (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2014. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation, and arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly- saccharides, glycoproteins, glycolipids, glycosides, and biopharmaceuticals. Much of this material is presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions, and applications to chemical synthesis. © 2018 Wiley Periodicals, Inc. Mass Spec Rev 37:353-491, 2018.
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Affiliation(s)
- David J Harvey
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7FZ, United Kingdom
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25
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Biosynthesis of levan from sucrose using a thermostable levansucrase from Lactobacillus reuteri LTH5448. Int J Biol Macromol 2018; 113:29-37. [DOI: 10.1016/j.ijbiomac.2018.01.187] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 01/21/2018] [Accepted: 01/29/2018] [Indexed: 11/18/2022]
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26
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He C, Yang Y, Zhao R, Qu J, Jin L, Lu L, Xu L, Xiao M. Rational designed mutagenesis of levansucrase from Bacillus licheniformis 8-37-0-1 for product specificity study. Appl Microbiol Biotechnol 2018; 102:3217-3228. [DOI: 10.1007/s00253-018-8854-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 02/08/2018] [Accepted: 02/10/2018] [Indexed: 11/28/2022]
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27
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Benini S, Toccafondi M, Rejzek M, Musiani F, Wagstaff BA, Wuerges J, Cianci M, Field RA. Glucose-1-phosphate uridylyltransferase from Erwinia amylovora: Activity, structure and substrate specificity. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1865:1348-1357. [PMID: 28844747 DOI: 10.1016/j.bbapap.2017.08.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 08/05/2017] [Accepted: 08/09/2017] [Indexed: 10/19/2022]
Abstract
Erwinia amylovora, a Gram-negative plant pathogen, is the causal agent of Fire Blight, a contagious necrotic disease affecting plants belonging to the Rosaceae family, including apple and pear. E. amylovora is highly virulent and capable of rapid dissemination in orchards; effective control methods are still lacking. One of its most important pathogenicity factors is the exopolysaccharide amylovoran. Amylovoran is a branched polymer made by the repetition of units mainly composed of galactose, with some residues of glucose, glucuronic acid and pyruvate. E. amylovora glucose-1-phosphate uridylyltransferase (UDP-glucose pyrophosphorylase, EC 2.7.7.9) has a key role in amylovoran biosynthesis. This enzyme catalyses the production of UDP-glucose from glucose-1-phosphate and UTP, which the epimerase GalE converts into UDP-galactose, the main building block of amylovoran. We determined EaGalU kinetic parameters and substrate specificity with a range of sugar 1-phosphates. At time point 120min the enzyme catalysed conversion of the sugar 1-phosphate into the corresponding UDP-sugar reached 74% for N-acetyl-α-d-glucosamine 1-phosphate, 28% for α-d-galactose 1-phosphate, 0% for α-d-galactosamine 1-phosphate, 100% for α-d-xylose 1-phosphate, 100% for α-d-glucosamine 1-phosphate, 70% for α-d-mannose 1-phosphate, and 0% for α-d-galacturonic acid 1-phosphate. To explain our results we obtained the crystal structure of EaGalU and augmented our study by docking the different sugar 1-phosphates into EaGalU active site, providing both reliable models for substrate binding and enzyme specificity, and a rationale that explains the different activity of EaGalU on the sugar 1-phosphates used. These data demonstrate EaGalU potential as a biocatalyst for biotechnological purposes, as an alternative to the enzyme from Escherichia coli, besides playing an important role in E. amylovora pathogenicity.
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Affiliation(s)
- Stefano Benini
- Bioorganic Chemistry and Bio-Crystallography laboratory (B2Cl), Faculty of Science and Technology, Free University of Bolzano, 39100 Bolzano, Italy.
| | - Mirco Toccafondi
- Bioorganic Chemistry and Bio-Crystallography laboratory (B2Cl), Faculty of Science and Technology, Free University of Bolzano, 39100 Bolzano, Italy
| | - Martin Rejzek
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Francesco Musiani
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, Viale G. Fanin 40, Bologna 40127, Italy
| | - Ben A Wagstaff
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Jochen Wuerges
- Bioorganic Chemistry and Bio-Crystallography laboratory (B2Cl), Faculty of Science and Technology, Free University of Bolzano, 39100 Bolzano, Italy
| | - Michele Cianci
- Department of Agricultural, Food and Environmental Sciences, Universita' Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona, Italy; Hamburg Outstation, Notkestrasse 85, 22607 Hamburg, Germany
| | - Robert A Field
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
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28
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Xu W, Yu S, Liu Q, Zhang T, Jiang B, Mu W. Enzymatic Production of Melibiose from Raffinose by the Levansucrase from Leuconostoc mesenteroides B-512 FMC. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:3910-3918. [PMID: 28453942 DOI: 10.1021/acs.jafc.7b01265] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Melibiose, which is an important reducing disaccharide formed by α-1,6 linkage between galactose and glucose, has been proven to have beneficial applications in both medicine and agriculture. In this study, a characterized levansucrase from Leuconostoc mesenteroides B-512 FMC was further used to study the bioproduction of melibiose from raffinose. The reaction conditions were optimized for melibiose synthesis. The optimal pH, temperature, substrate concentration, ratio of substrates, and units of enzymes were determined as pH 6.0, 45 °C, 210 g/L, 1:1 (210 g/L:210 g/L), and 5 U/mL, respectively. The transfructosylation product of raffinose was determined to be melibiose by FTIR and NMR. A high raffinose concentration was found to strongly favor the production of melibiose. When 210 g/L raffinose and 210 g/L lactose were catalyzed using 5 U/mL purified levansucrase at pH 6.0 and 45 °C, the maximal yield of melibiose was 88 g/L.
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Affiliation(s)
- Wei Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University , Wuxi, Jiangsu 214122, China
| | - Shuhuai Yu
- State Key Laboratory of Food Science and Technology, Jiangnan University , Wuxi, Jiangsu 214122, China
| | - Qian Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University , Wuxi, Jiangsu 214122, China
| | - Tao Zhang
- 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
- Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University , Wuxi, Jiangsu 214122, China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University , Wuxi, Jiangsu 214122, China
- Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University , Wuxi, Jiangsu 214122, China
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29
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Bartho JD, Bellini D, Wuerges J, Demitri N, Toccafondi M, Schmitt AO, Zhao Y, Walsh MA, Benini S. The crystal structure of Erwinia amylovora AmyR, a member of the YbjN protein family, shows similarity to type III secretion chaperones but suggests different cellular functions. PLoS One 2017; 12:e0176049. [PMID: 28426806 PMCID: PMC5398634 DOI: 10.1371/journal.pone.0176049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 04/04/2017] [Indexed: 11/18/2022] Open
Abstract
AmyR is a stress and virulence associated protein from the plant pathogenic Enterobacteriaceae species Erwinia amylovora, and is a functionally conserved ortholog of YbjN from Escherichia coli. The crystal structure of E. amylovora AmyR reveals a class I type III secretion chaperone-like fold, despite the lack of sequence similarity between these two classes of protein and lacking any evidence of a secretion-associated role. The results indicate that AmyR, and YbjN proteins in general, function through protein-protein interactions without any enzymatic action. The YbjN proteins of Enterobacteriaceae show remarkably low sequence similarity with other members of the YbjN protein family in Eubacteria, yet a high level of structural conservation is observed. Across the YbjN protein family sequence conservation is limited to residues stabilising the protein core and dimerization interface, while interacting regions are only conserved between closely related species. This study presents the first structure of a YbjN protein from Enterobacteriaceae, the most highly divergent and well-studied subgroup of YbjN proteins, and an in-depth sequence and structural analysis of this important but poorly understood protein family.
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Affiliation(s)
- Joseph D. Bartho
- Bioorganic Chemistry and Bio-Crystallography laboratory (B2Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, Bolzano, Italy
| | - Dom Bellini
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, United Kingdom
- Research Complex at Harwell, Harwell Science and Innovation Campus, Didcot, United Kingdom
| | - Jochen Wuerges
- Bioorganic Chemistry and Bio-Crystallography laboratory (B2Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, Bolzano, Italy
| | - Nicola Demitri
- Elettra–Sincrotrone Trieste, S.S 14 km 163.5 in Area Science Park, Basovizza, Trieste, Italy
| | - Mirco Toccafondi
- Bioorganic Chemistry and Bio-Crystallography laboratory (B2Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, Bolzano, Italy
| | - Armin O. Schmitt
- Bioorganic Chemistry and Bio-Crystallography laboratory (B2Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, Bolzano, Italy
- Georg-August-Universität Göttingen, Dept. Nutztierwissenschaften, Breeding informatics, Margarethe von Wrangell-Weg 7, Göttingen, Germany
| | - Youfu Zhao
- Department of Crop Sciences, University of Illinois, 1201 W. Gregory Dr., Urbana, IL, United States of America
| | - Martin A. Walsh
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, United Kingdom
- Research Complex at Harwell, Harwell Science and Innovation Campus, Didcot, United Kingdom
| | - Stefano Benini
- Bioorganic Chemistry and Bio-Crystallography laboratory (B2Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, Bolzano, Italy
- * E-mail:
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Ojha S, Rana N, Mishra S. Fructo-oligosaccharide synthesis by whole cells of Microbacterium paraoxydans. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.tetasy.2016.10.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Salomone-Stagni M, Musiani F, Benini S. Characterization and 1.57 Å resolution structure of the key fire blight phosphatase AmsI from Erwinia amylovora. Acta Crystallogr F Struct Biol Commun 2016; 72:903-910. [PMID: 27917839 PMCID: PMC5137468 DOI: 10.1107/s2053230x16018781] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 11/23/2016] [Indexed: 11/10/2022] Open
Abstract
AmsI is a low-molecular-weight protein tyrosine phosphatase that regulates the production of amylovoran in the Gram-negative bacterium Erwinia amylovora, a specific pathogen of rosaceous plants such as apple, pear and quince. Amylovoran is an exopolysaccharide that is necessary for successful infection. In order to shed light on AmsI, its structure was solved at 1.57 Å resolution at the same pH as its highest measured activity (pH 5.5). In the active site, a water molecule, bridging between the catalytic Arg15 and the reaction-product analogue sulfate, might be representative of the water molecule attacking the phospho-cysteine intermediate in the second step of the reaction mechanism.
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Affiliation(s)
- Marco Salomone-Stagni
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazza Università 5, 39100 Bolzano, Italy
| | - Francesco Musiani
- Department of Pharmacy and Biotechnology, University of Bologna, Viale G. Fanin 40, 40127 Bologna, Italy
| | - Stefano Benini
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazza Università 5, 39100 Bolzano, Italy
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Öner ET, Hernández L, Combie J. Review of Levan polysaccharide: From a century of past experiences to future prospects. Biotechnol Adv 2016; 34:827-844. [DOI: 10.1016/j.biotechadv.2016.05.002] [Citation(s) in RCA: 203] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 05/01/2016] [Accepted: 05/04/2016] [Indexed: 01/24/2023]
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Li M, Seo S, Karboune S. Bacillus amyloliquefaciens levansucrase-catalyzed the synthesis of fructooligosaccharides, oligolevan and levan in maple syrup-based reaction systems. Carbohydr Polym 2015; 133:203-12. [DOI: 10.1016/j.carbpol.2015.07.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Revised: 07/05/2015] [Accepted: 07/07/2015] [Indexed: 11/24/2022]
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The crystal structure of Erwinia amylovora levansucrase provides a snapshot of the products of sucrose hydrolysis trapped into the active site. J Struct Biol 2015. [DOI: 10.1016/j.jsb.2015.07.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Recent novel applications of levansucrases. Appl Microbiol Biotechnol 2015; 99:6959-69. [DOI: 10.1007/s00253-015-6797-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2015] [Revised: 06/22/2015] [Accepted: 06/24/2015] [Indexed: 01/12/2023]
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Adamberg S, Tomson K, Vija H, Puurand M, Kabanova N, Visnapuu T, Jõgi E, Alamäe T, Adamberg K. Degradation of Fructans and Production of Propionic Acid by Bacteroides thetaiotaomicron are Enhanced by the Shortage of Amino Acids. Front Nutr 2014; 1:21. [PMID: 25988123 PMCID: PMC4428435 DOI: 10.3389/fnut.2014.00021] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 11/19/2014] [Indexed: 12/23/2022] Open
Abstract
Bacteroides thetaiotaomicron is commonly found in the human colon and stabilizes its ecosystem by catabolism of various polysaccharides. A model of cross-talk between the metabolism of amino acids and fructans in B. thetaiotaomicron was proposed. The growth of B. thetaiotaomicron DSM 2079 in two defined media containing mineral salts and vitamins, and supplemented with either 20 or 2 amino acids, was studied in an isothermal microcalorimeter. The polyfructans inulin (from chicory) and levan (synthesized using levansucrase from Pseudomonas syringae), two fructooligosaccharide preparations with different composition, sucrose and fructose were tested as substrates. The calorimetric power-time curves were substrate specific and typically multiauxic. A surplus of amino acids reduced the consumption of longer oligosaccharides (degree of polymerization > 3). Bacterial growth was not detected either in the carbohydrate free medium containing amino acids or in the medium with inulin as a sole carbohydrate. In amino acid-restricted medium, fermentation leading to acetic acid formation was dominant at the beginning of growth (up to 24 h), followed by increased lactic acid production, and mainly propionic and succinic acids were produced at the end of fermentation. In the medium supplemented with 20 amino acids, the highest production of d-lactate (82 ± 33 mmol/gDW) occurred in parallel with extensive consumption (up to 17 mmol/gDW) of amino acids, especially Ser, Thr, and Asp. The production of Ala and Glu was observed at growth on all substrates, and the production was enhanced under amino acid deficiency. The study revealed the influence of amino acids on fructan metabolism in B. thetaiotaomicron and showed that defined growth media are invaluable in elucidating quantitative metabolic profiles of the bacteria. Levan was shown to act as an easily degradable substrate for B. thetaiotaomicron. The effect of levan on balancing or modifying colon microbiota will be studied in further experiments.
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Affiliation(s)
| | - Katrin Tomson
- Competence Center of Food and Fermentation Technologies , Tallinn , Estonia
| | - Heiki Vija
- National Institute of Chemical Physics and Biophysics , Tallinn , Estonia
| | - Marju Puurand
- Tallinn University of Technology , Tallinn , Estonia
| | - Natalja Kabanova
- Competence Center of Food and Fermentation Technologies , Tallinn , Estonia
| | - Triinu Visnapuu
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu , Tartu , Estonia
| | - Eerik Jõgi
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu , Tartu , Estonia
| | - Tiina Alamäe
- Department of Genetics, Institute of Molecular and Cell Biology, University of Tartu , Tartu , Estonia
| | - Kaarel Adamberg
- Tallinn University of Technology , Tallinn , Estonia ; Competence Center of Food and Fermentation Technologies , Tallinn , Estonia
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Benini S, Caputi L, Cianci M. Cloning, purification, crystallization and 1.57 Å resolution X-ray data analysis of AmsI, the tyrosine phosphatase controlling amylovoran biosynthesis in the plant pathogen Erwinia amylovora. ACTA CRYSTALLOGRAPHICA SECTION F-STRUCTURAL BIOLOGY COMMUNICATIONS 2014; 70:1693-6. [PMID: 25484228 DOI: 10.1107/s2053230x14024947] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 11/13/2014] [Indexed: 02/02/2023]
Abstract
The Gram-negative bacterium Erwinia amylovora is a destructive pathogen of plants belonging to the Rosaceae family. Amongst its pathogenicity factors, E. amylovora produces the exopolysaccharide amylovoran, which contributes to the occlusion of plant vessels, causing wilting of shoots and eventually resulting in plant death. Amylovoran biosynthesis requires the presence of 12 genes (from amsA to amsL) clustered in the ams region of the E. amylovora genome. They mostly encode glycosyl transferases (AmsG, AmsB, AmsD, AmsE, AmsJ and AmsK), proteins involved in amylovoran translocation and assembly (AmsH, AmsL and AmsC), and also a tyrosine kinase (AmsA) and a tyrosine phosphatase (AmsI), which are both involved in the regulation of amylovoran biosynthesis. The low-molecular-weight protein tyrosine phosphatase AmsI was overexpressed as a His6-tagged protein in Escherichia coli, purified and crystallized. X-ray diffraction data were collected to a maximum resolution of 1.57 Å in space group P3121.
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Affiliation(s)
- Stefano Benini
- Laboratory of Bioorganic Chemistry and Bio-Crystallography (B2Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, 39100 Bolzano, Italy
| | - Lorenzo Caputi
- Biological Chemistry Department, John Innes Centre, Norwich Research Park, Colney, Norwich NR4 7UH, England
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Optimization of levansucrase/endo-inulinase bi-enzymatic system for the production of fructooligosaccharides and oligolevans from sucrose. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.molcatb.2014.08.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Toccafondi M, Cianci M, Benini S. Expression, purification, crystallization and preliminary X-ray analysis of glucose-1-phosphate uridylyltransferase (GalU) from Erwinia amylovora. ACTA CRYSTALLOGRAPHICA SECTION F-STRUCTURAL BIOLOGY COMMUNICATIONS 2014; 70:1249-51. [PMID: 25195902 DOI: 10.1107/s2053230x14016458] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 07/15/2014] [Indexed: 11/10/2022]
Abstract
Glucose-1-phosphate uridylyltransferase from Erwinia amylovora CFPB1430 was expressed as a His-tag fusion protein in Escherichia coli. After tag removal, the purified protein was crystallized from 100 mM Tris pH 8.5, 2 M ammonium sulfate, 5% ethylene glycol. Diffraction data sets were collected to a maximum resolution of 2.46 Å using synchrotron radiation. The crystals belonged to the hexagonal space group P62, with unit-cell parameters a = 80.67, b = 80.67, c = 169.18. The structure was solved by molecular replacement using the structure of the E. coli enzyme as a search model.
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Affiliation(s)
- Mirco Toccafondi
- Laboratory of Bioorganic Chemistry and Bio-Crystallography (B2Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, 39100 Bolzano, Italy
| | | | - Stefano Benini
- Laboratory of Bioorganic Chemistry and Bio-Crystallography (B2Cl), Faculty of Science and Technology, Free University of Bolzano, Piazza Università 5, 39100 Bolzano, Italy
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High-throughput assay of levansucrase variants in search of feasible catalysts for the synthesis of fructooligosaccharides and levan. Molecules 2014; 19:8434-55. [PMID: 24955639 PMCID: PMC6271050 DOI: 10.3390/molecules19068434] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 06/10/2014] [Accepted: 06/10/2014] [Indexed: 12/03/2022] Open
Abstract
Bacterial levansucrases polymerize fructose residues of sucrose to β-2,6 linked fructans—fructooligosaccharides (FOS) and levan. While β-2,1-linked FOS are widely recognized as prebiotics, the health-related effects of β-2,6 linked FOS are scarcely studied as they are not commercially available. Levansucrase Lsc3 (Lsc-3) of Pseudomonas syringae pv. tomato has very high catalytic activity and stability making it a promising biotechnological catalyst for FOS and levan synthesis. In this study we evaluate feasibility of several high-throughput methods for screening and preliminary characterization of levansucrases using 36 Lsc3 mutants as a test panel. Heterologously expressed and purified His-tagged levansucrase variants were studied for: (1) sucrose-splitting activity; (2) FOS production; (3) ability and kinetics of levan synthesis; (4) thermostability in a Thermofluor assay. Importantly, we show that sucrose-splitting activity as well as the ability to produce FOS can both be evaluated using permeabilized levansucrase-expressing E. coli transformants as catalysts. For the first time we demonstrate the key importance of Trp109, His113, Glu146 and Glu236 for the catalysis of Lsc3. Cost-effective and high-throughput methods presented here are applicable not only in the levansucrase assay, but have a potential to be adapted for high-throughput (automated) study of other enzymes.
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