Wataru Saburi

Research Faculty of Agriculture　Fundamental AgriScience Research　Bioscience and ChemistryAssociate Professor
Last Updated :2025/07/05

■Researcher basic information

Degree

  • Mar. 2006

Researchmap personal page

Home Page URL

J-Global ID

Research Keyword

  • Protein engineering
  • Applied microbiology
  • Carbohydrate synthesis
  • Enzyme chemistry
  • Applied biochemistry

Research Field

  • Life sciences, Applied biochemistry

Educational Organization

■Career

Career

  • Jul. 2020 - Present
    Hokkaido University, Research Faculty of Agriculture, Associate Professor
  • Apr. 2019 - Jun. 2020
    Hokkaido University, Graduate School of Agriculture Research Faculty of Agriculture, 講師
  • Oct. 2010 - Mar. 2019
    Hokkaido University, Graduate School of Agriculture Research Faculty of Agriculture, 助教
  • Apr. 2006 - Sep. 2010
    日本食品化工株式会社, 研究所, 研究員

Educational Background

  • Apr. 2001 - Mar. 2006, Hokkaido University, 大学院農学研究科
  • Apr. 1997 - Mar. 2001, Hokkaido University, Faculty of Agriculture, Department of Applied Bioscience

Committee Memberships

  • Sep. 2023 - Present
    日本応用糖質科学会, 評議員
  • May 2023 - Present
    日本農芸化学会, 北海道支部庶務幹事
  • Jul. 2021 - Present
    日本応用糖質科学会, 北海道支部事務局長
  • Sep. 2017 - Present
    応用糖質科学会, Journal of Applied Glycoscience編集委員, Society
  • Mar. 2021 - Mar. 2025
    Japan Society for Bioscience, Biotechnology, and Agrochemistry, Editor of Bioscience, Biotechnology, and Biochemistry, Society
  • Apr. 2011 - Mar. 2013
    日本農芸化学会, 北海道支部会計幹事, Society

■Research activity information

Awards

  • Sep. 2020, 日本応用糖質科学会, 奨励賞　　　　　　　　　　　　　　　
    佐分利 亘
  • Sep. 2018, 日本応用糖質科学会, ポスター賞　　　　　　　　　　　　　　　
    佐分利 亘
  • Sep. 2017, 日本応用糖質科学会, ポスター賞　　　　　　　　　　　　　　　
    佐分利 亘
  • Apr. 2017, Congress on Gastrointestinal Function, James Russel Award,　　　　　　　　　　　　　　　
    Saburi Wataru
  • Sep. 2016, 日本応用糖質科学会, ポスター賞　　　　　　　　　　　　　　　
    佐分利 亘
  • Mar. 2015, 日本農芸化学会, 農芸化学奨励賞　　　　　　　　　　　　　　　
    佐分利 亘
  • Oct. 2014, 植物化学調節学会, ポスター賞　　　　　　　　　　　　　　　
    佐分利 亘
  • Jun. 2013, 酵素応用シンポジウム, 研究奨励賞　　　　　　　　　　　　　　　
    佐分利 亘

Papers

  • Biochemical and structural analysis of the mechanism for the catalysis and specificity of cellobiose 2-epimerase from Rhodothermus marinus.
    Wataru Saburi, Hirohiko Muto-Fukiya, Nongluck Jaito, Koji Kato, Jian Yu, Min Yao, Haruhide Mori
    Bioscience, biotechnology, and biochemistry, 22 Mar. 2025, [Peer-reviewed], [Lead author, Corresponding author], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal, Cellobiose 2-epimerase (CE) catalyzes C-2 epimerization of reducing end d-glucose/d-mannose residue of β-(1→4)-disaccharides, and also slightly catalyzes aldose-ketose conversion. In this study, we investigated the structure-function relationship of Rhodothermus marinus CE (RmCEs). In 2H2O, 2H replaced the 2-H of the reducing end sugar residue, suggesting a proton abstraction-addition mechanism via the cis-enediolate intermediate. The structure of the RmCE-mannobiitol complex showed that His259 was suitable for abstracting 2-H from d-mannose residue, whereas His390 was suitable for the d-glucose residue. H259A and H390A mutations abolished activity for Galβ1-4Man and Galβ1-4Glc formation from Galβ1-4Fru, respectively, and these mutants catalyzed both epimerization and isomerization to Galβ1-4Glc and Galβ1-4Man, respectively. Ala substitution of the residues interacting with the 2-O of the reducing end sugar residue significantly reduced the velocity for epimerization, but not for isomerization. Trp385, stacked onto the non-reducing-end sugar residues of disaccharides, was shown to be important for disaccharide specificity.
  • Molecular mechanism for the substrate specificity of Arthrobacter globiformis M6 α-glucosidase CmmB, belonging to glycoside hydrolase family 13 subfamily 30
    Wataru Saburi, Takayoshi Tagami, Takuya Usui, Jian Yu, Toyoyuki Ose, Min Yao, Haruhide Mori
    Food Bioscience, 61, 104516, 104516, Elsevier BV, Oct. 2024, [Peer-reviewed], [Lead author, Corresponding author]
    Scientific journal
  • Comparisons of the amylolytic enzymes and malt starch hydrolysates of two barley cultivars, Hokudai 1 (the first cultivar developed in Japan) and Kitanohoshi (currently used cultivar for beer production)
    Wataru Saburi, Haruhide Mori
    Bioscience, Biotechnology, and Biochemistry, 88, 10, 1180, 1187, Oxford University Press (OUP), 11 Jul. 2024, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
    English, Scientific journal, Abstract

    Starch degradation in malted barley produces yeast-fermentable sugars. In this study, we compared the amylolytic enzymes and composition of the malt starch hydrolysates of two barley cultivars, Hokudai 1 (the first cultivar established in Japan) and Kitanohoshi (the currently used cultivar for beer production). Hokudai 1 malt contained lower activity of amylolytic enzymes than Kitanohoshi malt, although these cultivars contained α-amylase AMY2 and β-amylase Bmy1 as the predominant enzymes. Malt starch hydrolysate of Hokudai 1 contained more limit dextrin and less yeast-fermentable sugars than that of Kitanohoshi. In mixed malt saccharification, a high Hokudai 1 malt ratio increased the limit dextrin levels and decreased the maltotriose and maltose levels. Even though Kitanohoshi malt contained more amylolytic enzymes than Hokudai 1 malt, addition of Kitanohoshi extract containing the amylolytic enzymes did not enhance malt starch degradation of Hokudai 1. Hokudai 1 malt starch was less degradable than Kitanohoshi malt starch.
  • Extraction and antioxidant capacity of mycosporine-like amino acids from red algae in Japan.
    Ryuya Yamamoto, Shigeru Toriumi, Chikara Kawagoe, Wataru Saburi, Hideki Kishimura, Yuya Kumagai
    Bioscience, biotechnology, and biochemistry, 88, 7, 830, 838, 29 Apr. 2024, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Mycosporine-like amino acids (MAAs) are the natural UV absorbing compounds with antioxidant activity found in microalgae and macroalgae. We collected red algae Asparagopsis taxiformis, Meristotheca japonica, and Polysiphonia senticulosa from Nagasaki, where UV radiation is more intense than in Hokkaido, and investigated the effect of UV radiation on MAAs content. It was suggested that A. taxiformis and M. japonica contained shinorine and palythine, while UV absorbing compound in P. senticulosa could not be identified. The amounts of these MAAs were lower compared to those from Hokkaido. Despite an increase in UV radiation in both region from February to April, MAAs contents of red algae from Nagasaki slightly decreased, while that from Hokkaido significantly decreased. This difference was suggested the amount of inorganic nitrogen in the ocean. Antioxidant activity of MAAs increased under alkaline conditions. The extract containing MAAs from P. senticulosa showed the highest antioxidant activity among four red algae.
  • Tunable structure of chimeric isomaltomegalosaccharides with double α-(1 → 4)-glucosyl chains enhances the solubility of water-insoluble bioactive compounds
    Weeranuch Lang, Takayoshi Tagami, Yuya Kumagai, Seiya Tanaka, Hye-Jin Kang, Masayuki Okuyama, Wataru Saburi, Haruhide Mori, Tohru Hira, Chaehun Lee, Takuya Isono, Toshifumi Satoh, Hiroshi Hara, Takayuki Kurokawa, Nobuo Sakairi, Yoshiaki Yuguchi, Atsuo Kimura
    Carbohydrate Polymers, 319, 121185, 121185, Elsevier BV, Nov. 2023, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal, Isomaltomegalosaccharides with α-(1 → 4) and α-(1 → 6)-segments solubilize water-insoluble ligands since the former complexes with the ligand and the latter solubilizes the complex. Previously, we enzymatically synthesized isomaltomegalosaccharide with a single α-(1 → 4)-segment at the reducing end (S-IMS) by dextran dextrinase (DDase), but the chain length [average degree of polymerization (DP) ≤ 9] was insufficient for strong encapsulation. We hypothesized that the conjugation of longer α-(1 → 4)-segment afforded the promising function although DDase is incapable to do so. In this study, the cyclodextrin glucanotransferase-catalyzed coupling reaction of α-cyclodextrin to S-IMS synthesized a new α-(1 → 4)-segment at the nonreducing end (N-4S) of S-IMS to form D-IMS [IMS harboring double α-(1 → 4)-segments]. The length of N-4S was modulated by the ratio between α-cyclodextrin and S-IMS, generating N-4Ss with DPs of 7-50. Based on phase-solubility analysis, D-IMS-28.3/13/3 bearing amylose-like helical N-4S with DP of 28.3 displayed a water-soluble complex with aromatic drugs and curcumin. Small-angle X-ray scattering revealed the chain adapted to rigid in solution in which the radius of gyration was estimated to 2.4 nm. Furthermore, D-IMS with short N-4S solubilized flavonoids of less-soluble multifunctional substances. In our research, enzyme-generated functional biomaterials from DDase were developed to maximize the hydrophobic binding efficacy towards water-insoluble bioactive compounds.
  • Molecular mechanism for endo-type action of glycoside hydrolase family 55 endo-β-1,3-glucanase on β1-3/1-6-glucan.
    Tomoya Ota, Wataru Saburi, Takayoshi Tagami, Jian Yu, Shiro Komba, Linda Elizabeth Jewell, Tom Hsiang, Ryozo Imai, Min Yao, Haruhide Mori
    The Journal of biological chemistry, 299, 11, 105294, 105294, 27 Sep. 2023, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal, The glycoside hydrolase family 55 (GH55) includes inverting exo-β-1,3-glucosidases and endo-β-1,3-glucanases, acting on laminarin, which is a β1-3/1-6-glucan consisting of a β1-3/1-6-linked main chain and β1-6-linked branches. Despite their different modes of action toward laminarin, endo-β-1,3-glucanases share with exo-β-1,3-glucosidases conserved residues that form the dead-end structure of subsite -1. Here, we investigated the mechanism of endo-type action on laminarin by GH55 endo-β-1,3-glucanase MnLam55A, identified from Microdochium nivale. MnLam55A, like other endo-β-1,3-glucanases, degraded internal β-d-glucosidic linkages of laminarin, producing more reducing sugars than the sum of d-glucose and gentiooligosaccharides detected. β1-3-Glucans lacking β1-6-linkages in the main chain were not hydrolyzed. NMR analysis of the initial degradation of laminarin revealed that MnLam55A preferentially cleaved the non-reducing terminal β1-3-linkage of the laminarioligosaccharide moiety at the reducing end side of the main chain β1-6-linkage. MnLam55A liberates d-glucose from laminaritriose and longer laminarioligosaccharides, but kcat/Km values to laminarioligosaccharides (≤4.21 s-1mM-1) were much lower than to laminarin (5,920 s-1mM-1). These results indicate that β-glucan binding to the minus subsites of MnLam55A, including exclusive binding of the gentiobiosyl moiety to subsites -1 and -2, is required for high hydrolytic activity. A crystal structure of MnLam55A, determined at 2.4 Å resolution, showed that MnLam55A adopts an overall structure and catalytic site similar to those of exo-β-1,3-glucosidases. However, MnLam55A possesses an extended substrate-binding cleft that is expected to form the minus subsites. Sequence comparison suggested that other endo-type enzymes share the extended cleft structure. The specific hydrolysis of internal linkages in laminarin is presumably common to GH55 endo-β-1,3-glucanases.
  • Hydrolysis-transglycosylation of sucrose and production of β-(2→1)-fructan by inulosucrase from Neobacillus drentensis 57N.
    Yusuke Kido, Wataru Saburi, Taizo Nagura, Haruhide Mori
    Bioscience, biotechnology, and biochemistry, 87, 10, 1169, 1182, 21 Sep. 2023, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Inulin, β-(2→1)-fructan, is a beneficial polysaccharide used as a functional food ingredient. Microbial inulosucrases (ISs), catalyzing β-(2→1)-transfructosylation, produce β-(2→1)-fructan from sucrose. In this study, we identified a new IS (NdIS) from the soil isolate, Neobacillus drentensis 57N. Sequence analysis revealed that, like other Bacillaceae ISs, NdIS consists of a glycoside hydrolase family 68 domain and shares most of the 1-kestose-binding residues of the archaeal IS, InuHj. Native and recombinant NdIS were characterized. NdIS is a homotetramer. It does not require calcium for activity. High performance liquid chromatography and 13C-nuclear magnetic resonance indicated that NdIS catalyzed the hydrolysis and β-(2→1)-transfructosylation of sucrose to synthesize β-(2→1)-fructan with chain lengths of 42 or more residues. The rate dependence on sucrose concentration followed hydrolysis-transglycosylation kinetics, and a 50% transglycosylation ratio was obtained at 344 m m sucrose. These results suggest that transfructosylation from sucrose to β-(2→1)-fructan occurs predominantly to elongate the fructan chain because sucrose is an unfavorable acceptor.
  • Chemical synthesis of oligosaccharide derivatives with partial structure of β1-3/1-6 glucan, using monomeric units for the formation of β1-3 and β1-6 glucosidic linkages.
    Tomoya Ota, Wataru Saburi, Shiro Komba, Haruhide Mori
    Bioscience, biotechnology, and biochemistry, 87, 10, 1111, 1121, 05 Jul. 2023, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal, β1-3/1-6 Glucans, known for their diverse structures, comprise a β1-3-linked main chain and β1-6-linked short branches. Laminarin, a β1-3/1-6 glucan extracted from brown seaweed, for instance, includes β1-6 linkages even in the main chain. The diverse structures provide various beneficial functions of the glucan. To investigate the relationship between structure and functionality, and to enable the characterization of β1-3/1-6 glucan-metabolizing enzymes, oligosaccharides containing exact structures of β1-3/1-6 glucans are required. We synthesized the monomeric units for the synthesis of β1-3/1-6 mixed-linked glucooligosaccharides. 2-(Trimethylsilyl)ethyl 2-O-benzoyl-4,6-O-benzylidene-β-d-glucopyranoside served as an acceptor in the formation of β1-3 linkages. Phenyl 2-O-benzoyl-4,6-O-benzylidene-3-O-(tert-butyldiphenylsilyl)-1-thio-β-d-glucopyranoside and phenyl 2,3-di-O-benzoyl-4,6-di-O-levulinyl-1-thio-β-d-glucopyranoside acted as donors, synthesizing acceptors suitable for the formation of β1-3- and β1-6-linkages, respectively. These were used to synthesize a derivative of Glcβ1-6Glcβ1-3Glcβ1-3Glc, demonstrating that the proposed route can be applied to synthesize the main chain of β-glucan, with the inclusion of both β1-3 and β1-6 linkages.
  • Structural insights into the substrate specificity and activity of a novel mannose 2-epimerase from Runella slithyformis.
    Hang Wang, Xiaomei Sun, Wataru Saburi, Saki Hashiguchi, Jian Yu, Toyoyuki Ose, Haruhide Mori, Min Yao
    Acta crystallographica. Section D, Structural biology, 79, Pt 7, 585, 595, 01 Jul. 2023, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal, Mannose 2-epimerase (ME), a member of the acylglucosamine 2-epimerase (AGE) superfamily that catalyzes epimerization of D-mannose and D-glucose, has recently been characterized to have potential for D-mannose production. However, the substrate-recognition and catalytic mechanism of ME remains unknown. In this study, structures of Runella slithyformis ME (RsME) and its D254A mutant [RsME(D254A)] were determined in their apo forms and as intermediate-analog complexes [RsME-D-glucitol and RsME(D254A)-D-glucitol]. RsME possesses the (α/α)6-barrel of the AGE superfamily members but has a unique pocket-covering long loop (loopα7-α8). The RsME-D-glucitol structure showed that loopα7-α8 moves towards D-glucitol and closes the active pocket. Trp251 and Asp254 in loopα7-α8 are only conserved in MEs and interact with D-glucitol. Kinetic analyses of the mutants confirmed the importance of these residues for RsME activity. Moreover, the structures of RsME(D254A) and RsME(D254A)-D-glucitol revealed that Asp254 is vital for binding the ligand in a correct conformation and for active-pocket closure. Docking calculations and structural comparison with other 2-epimerases show that the longer loopα7-α8 in RsME causes steric hindrance upon binding to disaccharides. A detailed substrate-recognition and catalytic mechanism for monosaccharide-specific epimerization in RsME has been proposed.
  • Identification and characterization of extracellular GH3 β-glucosidase from the pink snow mold fungus, Microdochium nivale.
    Tomoya Ota, Wataru Saburi, Linda Elizabeth Jewell, Tom Hsiang, Ryozo Imai, Haruhide Mori
    Bioscience, biotechnology, and biochemistry, 87, 7, 707, 716, 23 Jun. 2023, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal, Glycoside hydrolase family 3 (GH3) β-glucosidase exists in many filamentous fungi. In phytopathogenic fungi, it is involved in fungal growth and pathogenicity. Microdochium nivale is a severe phytopathogenic fungus of grasses and cereals and is the causal agent of pink snow mold, but its β-glucosidase has not been identified. In this study, a GH3 β-glucosidase of M. nivale (MnBG3A) was identified and characterized. Among various p-nitrophenyl β-glycosides, MnBG3A showed activity on d-glucoside (pNP-Glc) and slight activity on d-xyloside. In the pNP-Glc hydrolysis, substrate inhibition occurred (Kis = 1.6 m m), and d-glucose caused competitive inhibition (Ki = 0.5 m m). MnBG3A acted on β-glucobioses with β1-3, -6, -4, and -2 linkages, in descending order of kcat/Km. In contrast, the regioselectivity for newly formed products was limited to β1-6 linkage. MnBG3A has similar features to those of β-glucosidases from Aspergillus spp., but higher sensitivity to inhibitory effects.
  • Alteration of Substrate Specificity and Transglucosylation Activity of GH13_31 α-Glucosidase from Bacillus sp. AHU2216 through Site-Directed Mutagenesis of Asn258 on β→α Loop 5
    Waraporn Auiewiriyanukul, Wataru Saburi, Tomoya Ota, Jian Yu, Koji Kato, Min Yao, Haruhide Mori
    Molecules, 28, 7, 3109, 3109, MDPI AG, 30 Mar. 2023, [Peer-reviewed], [Corresponding author], [International Magazine]
    English, Scientific journal, α-Glucosidase catalyzes the hydrolysis of α-d-glucosides and transglucosylation. Bacillus sp. AHU2216 α-glucosidase (BspAG13_31A), belonging to the glycoside hydrolase family 13 subfamily 31, specifically cleaves α-(1→4)-glucosidic linkages and shows high disaccharide specificity. We showed previously that the maltose moiety of maltotriose (G3) and maltotetraose (G4), covering subsites +1 and +2 of BspAG13_31A, adopts a less stable conformation than the global minimum energy conformation. This unstable d-glucosyl conformation likely arises from steric hindrance by Asn258 on β→α loop 5 of the catalytic (β/α)8-barrel. In this study, Asn258 mutants of BspAG13_31A were enzymatically and structurally analyzed. N258G/P mutations significantly enhanced trisaccharide specificity. The N258P mutation also enhanced the activity toward sucrose and produced erlose from sucrose through transglucosylation. N258G showed a higher specificity to transglucosylation with p-nitrophenyl α-d-glucopyranoside and maltose than the wild type. E256Q/N258G and E258Q/N258P structures in complex with G3 revealed that the maltose moiety of G3 bound at subsites +1 and +2 adopted a relaxed conformation, whereas a less stable conformation was taken in E256Q. This structural difference suggests that stabilizing the G3 conformation enhances trisaccharide specificity. The E256Q/N258G-G3 complex formed an additional hydrogen bond between Met229 and the d-glucose residue of G3 in subsite +2, and this interaction may enhance transglucosylation.
  • Function and structure of Lacticaseibacillus casei GH35 β-galactosidase LBCZ_0230 with high hydrolytic activity to lacto-N-biose I and galacto-N-biose
    Saburi Wataru, Tomoya Ota, Koji Kato, Takayoshi Tagami, Keitaro Yamashita, Min Yao, Haruhide Mori
    Journal of Applied Glycoscience, 70, 2, 43, 52, The Japanese Society of Applied Glycoscience, 11 Mar. 2023, [Peer-reviewed], [Lead author, Corresponding author], [Domestic magazines]
    English, Scientific journal, β-Galactosidase (EC 3.2.1.23) hydrolyzes β-D-galactosidic linkages at the non-reducing end of substrates to produce β-D-galactose. Lacticaseibacillus casei is one of the most widely utilized probiotic species of lactobacilli. It possesses a putative β-galactosidase belonging to glycoside hydrolase family 35 (GH35). This enzyme is encoded by the gene included in the gene cluster for utilization of lacto-N-biose I (LNB; Galβ1-3GlcNAc) and galacto-N-biose (GNB; Galβ1-3GalNAc) via the phosphoenolpyruvate: sugar phosphotransferase system. The GH35 protein (GnbG) from L. casei BL23 is predicted to be 6-phospho-β-galactosidase (EC 3.2.1.85). However, its 6-phospho-β-galactosidase activity has not yet been examined, whereas its hydrolytic activity against LNB and GNB has been demonstrated. In this study, L. casei JCM1134 LBCZ_0230, homologous to GnbG, was characterized enzymatically and structurally. A recombinant LBCZ_0230, produced in Escherichia coli, exhibited high hydrolytic activity toward o-nitrophenyl β-D-galactopyranoside, p-nitrophenyl β-D-galactopyranoside, LNB, and GNB, but not toward o-nitrophenyl 6-phospho-β-D-galactopyranoside. Crystal structure analysis indicates that the structure of subsite -1 of LBCZ_0230 is very similar to that of Streptococcus pneumoniae β-galactosidase BgaC and not suitable for binding to 6-phospho-β-D-galactopyranoside. These biochemical and structural analyses indicate that LBCZ_0230 is a β-galactosidase. According to the prediction of LNB's binding mode, aromatic residues, Trp190, Trp240, Trp243, Phe244, and Tyr458, form hydrophobic interactions with N-acetyl-D-glucosamine residue of LNB at subsite +1.
  • Discovery of solabiose phosphorylase and its application for enzymatic synthesis of solabiose from sucrose and lactose
    Wataru Saburi, Takanori Nihira, Hiroyuki Nakai, Motomitsu Kitaoka, Haruhide Mori
    Scientific Reports, 12, 1, 259, 259, Springer Science and Business Media LLC, Dec. 2022, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
    English, Scientific journal, AbstractGlycoside phosphorylases (GPs), which catalyze the reversible phosphorolysis of glycosides, are promising enzymes for the efficient production of glycosides. Various GPs with new catalytic activities are discovered from uncharacterized proteins phylogenetically distant from known enzymes in the past decade. In this study, we characterized Paenibacillus borealis PBOR_28850 protein, belonging to glycoside hydrolase family 94. Screening of acceptor substrates for reverse phosphorolysis, in which α-d-glucose 1-phosphate was used as the donor substrate, revealed that the recombinant PBOR_28850 produced in Escherichia coli specifically utilized d-galactose as an acceptor and produced solabiose (β-d-Glcp-(1 → 3)-d-Gal). This indicates that PBOR_28850 is a new GP, solabiose phosphorylase. PBOR_28850 catalyzed the phosphorolysis and synthesis of solabiose through a sequential bi-bi mechanism involving the formation of a ternary complex. The production of solabiose from lactose and sucrose has been established. Lactose was hydrolyzed to d-galactose and d-glucose by β-galactosidase. Phosphorolysis of sucrose and synthesis of solabiose were then coupled by adding sucrose, sucrose phosphorylase, and PBOR_28850 to the reaction mixture. Using 210 mmol lactose and 280 mmol sucrose, 207 mmol of solabiose was produced. Yeast treatment degraded the remaining monosaccharides and sucrose without reducing solabiose. Solabiose with a purity of 93.7% was obtained without any chromatographic procedures.
  • Functional characterization of a novel GH94 glycoside phosphorylase, 3-O-β-d-glucopyranosyl β-d-glucuronide phosphorylase, and implication of the metabolic pathway of acidic carbohydrates in Paenibacillus borealis.
    Naoto Isono, Emi Mizutani, Haruka Hayashida, Hirotaka Katsuzaki, Wataru Saburi
    Biochemical and biophysical research communications, 625, 60, 65, 15 Oct. 2022, [Peer-reviewed], [Last author], [International Magazine]
    English, Scientific journal, Glycoside hydrolase family 94 (GH94) contains enzymes that reversibly catalyze the phosphorolysis of β-glycosides. We conducted this study to investigate a GH94 protein (PBOR_13355) encoded in the genome of Paenibacillus borealis DSM 13188 with low sequence identity to known phosphorylases. Screening of acceptor substrates for reverse phosphorolysis in the presence of α-d-glucose 1-phosphate as a donor substrate showed that PBOR_13355 utilized d-glucuronic acid and p-nitrophenyl β-d-glucuronide as acceptors. In the reaction with d-glucuronic acid, 3-O-β-d-glucopyranosyl-d-glucuronic acid was synthesized. PBOR_13355 showed a higher apparent catalytic efficiency to p-nitrophenyl β-d-glucuronide than to d-glucuronic acid, and thus, PBOR_13355 was concluded to be a novel glycoside phosphorylase, 3-O-β-d-glucopyranosyl β-d-glucuronide phosphorylase. PBOR_13360, encoded by the gene immediately downstream of the PBOR_13355 gene, was shown to be β-glucuronidase. Collectively, PBOR_13355 and PBOR_13360 are predicted to work together in the cytosol to metabolize oligosaccharides containing the 3-O-β-d-glucopyranosyl β-d-glucuronide structure released from bacterial and plant acidic carbohydrates.
  • Characterization of Antioxidant Activity of Heated Mycosporine-like Amino Acids from Red Alga Dulse Palmaria palmata in Japan.
    Yuki Nishida, Wataru Saburi, Yoshikatsu Miyabe, Hideki Kishimura, Yuya Kumagai
    Marine drugs, 20, 3, 01 Mar. 2022, [Peer-reviewed], [International Magazine]
    English, Scientific journal, We recently demonstrated the monthly variation and antioxidant activity of mycosporine-like amino acids (MAAs) from red alga dulse in Japan. The antioxidant activity of MAAs in acidic conditions was low compared to that in neutral and alkali conditions, but we found strong antioxidant activity from the heated crude MAA fraction in acidic conditions. In this study, we identified and characterized the key compounds involved in the antioxidant activity of this fraction. We first isolated two MAAs, palythine, and porphyra-334, from the fraction and evaluated the activities of the two MAAs when heated. MAAs possess absorption maxima at around 330 nm, while the heated MAAs lost this absorption. The heated MAAs showed a high ABTS radical scavenging activity at pH 5.8-8.0. We then determined the structure of heated palythine via ESI-MS and NMR analyses and speculated about the putative antioxidant mechanism. Finally, a suitable production condition of the heated compounds was determined at 120 °C for 30 min at pH 8.0. We revealed compounds from red algae with antioxidant activities at a wide range of pH values, and this information will be useful for the functional processing of food.
  • Substrate specificity of glycoside hydrolase family 1 β-glucosidase AtBGlu42 from Arabidopsis thaliana and its molecular mechanism.
    Shu Horikoshi, Wataru Saburi, Jian Yu, Hideyuki Matsuura, James R Ketudat Cairns, Min Yao, Haruhide Mori
    Bioscience, biotechnology, and biochemistry, 86, 2, 231, 245, 24 Jan. 2022, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal, Plants possess many glycoside hydrolase family 1 (GH1) β-glucosidases, which physiologically function in cell wall metabolism and activation of bioactive substances, but most remain uncharacterized. One GH1 isoenzyme AtBGlu42 in Arabidopsis thaliana has been identified to hydrolyze scopolin using the gene deficient plants, but no enzymatic properties were obtained. Its sequence similarity to another functionally characterized enzyme Os1BGlu4 in rice suggests that AtBGlu42 also acts on oligosaccharides. Here, we show that the recombinant AtBGlu42 possesses high kcat/Km not only on scopolin, but also on various β-glucosides, cellooligosaccharides, and laminarioligosaccharides. Of the cellooligosaccharides, cellotriose was the most preferred. The crystal structure, determined at 1.7 Å resolution, suggests that Arg342 gives unfavorable binding to cellooligosaccharides at subsite +3. The mutants R342Y and R342A showed the highest preference on cellotetraose or cellopentaose with increased affinities at subsite +3, indicating that the residues at this position have an important role for chain length specificity.
  • A practical approach to producing isomaltomegalosaccharide using dextran dextrinase from Gluconobacter oxydans ATCC 11894.
    Weeranuch Lang, Yuya Kumagai, Juri Sadahiro, Wataru Saburi, Rakrudee Sarnthima, Takayoshi Tagami, Masayuki Okuyama, Haruhide Mori, Nobuo Sakairi, Doman Kim, Atsuo Kimura
    Applied microbiology and biotechnology, 106, 2, 689, 698, Jan. 2022, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Dextran dextrinase (DDase) catalyzes formation of the polysaccharide dextran from maltodextrin. During the synthesis of dextran, DDase also generates the beneficial material isomaltomegalosaccharide (IMS). The term megalosaccharide is used for a saccharide having DP = 10-100 or 10-200 (DP, degree of polymerization). IMS is a chimeric glucosaccharide comprising α-(1 → 6)- and α-(1 → 4)-linked portions at the nonreducing and reducing ends, respectively, in which the α-(1 → 4)-glucosyl portion originates from maltodextrin of the substrate. In this study, IMS was produced by a practical approach using extracellular DDase (DDext) or cell surface DDase (DDsur) of Gluconobacter oxydans ATCC 11894. DDsur was the original form, so we prepared DDext via secretion from intact cells by incubating with 0.5% G6/G7 (maltohexaose/maltoheptaose); this was followed by generation of IMS from various concentrations of G6/G7 substrate at different temperatures for 96 h. However, IMS synthesis by DDext was limited by insufficient formation of α-(1 → 6)-glucosidic linkages, suggesting that DDase also catalyzes elongation of α-(1 → 4)-glucosyl chain. For production of IMS using DDsur, intact cells bearing DDsur were directly incubated with 20% G6/G7 at 45 °C by optimizing conditions such as cell concentration and agitation efficiency, which resulted in generation of IMS (average DP = 14.7) with 61% α-(1 → 6)-glucosyl content in 51% yield. Increases in substrate concentration and agitation efficiency were found to decrease dextran formation and increase IMS production, which improved the reaction conditions for DDext. Under modified conditions (20% G6/G7, agitation speed of 100 rpm at 45 °C), DDext produced IMS (average DP = 14.5) with 65% α-(1 → 6)-glucosyl content in a good yield of 87%. KEY POINTS: • Beneficial IMS was produced using thermostabilized DDase. • Optimum conditions for reduced dextran formation were successfully determined. • A practical approach was established to provide IMS with a great yield of 87%.
  • A Ubiquitously Expressed UDP-Glucosyltransferase, UGT74J1, Controls Basal Salicylic Acid Levels in Rice.
    Daisuke Tezuka, Hideyuki Matsuura, Wataru Saburi, Haruhide Mori, Ryozo Imai
    Plants (Basel, Switzerland), 10, 9, 10 Sep. 2021, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Salicylic acid (SA) is a phytohormone that regulates a variety of physiological and developmental processes, including disease resistance. SA is a key signaling component in the immune response of many plant species. However, the mechanism underlying SA-mediated immunity is obscure in rice (Oryza sativa). Prior analysis revealed a correlation between basal SA level and blast resistance in a range of rice varieties. This suggested that resistance might be improved by increasing basal SA level. Here, we identified a novel UDP-glucosyltransferase gene, UGT74J1, which is expressed ubiquitously throughout plant development. Mutants of UGT74J1 generated by genome editing accumulated high levels of SA under non-stressed conditions, indicating that UGT74J1 is a key enzyme for SA homeostasis in rice. Microarray analysis revealed that the ugt74j1 mutants constitutively overexpressed a set of pathogenesis-related (PR) genes. An inoculation assay demonstrated that these mutants had increased resistance against rice blast, but they also exhibited stunted growth phenotypes. To our knowledge, this is the first report of a rice mutant displaying SA overaccumulation.
  • β-(1→4)-Mannobiose Acts as an Immunostimulatory Molecule in Murine Dendritic Cells by Binding the TLR4/MD-2 Complex.
    Ting-Yu Cheng, Yen-Ju Lin, Wataru Saburi, Stefan Vieths, Stephan Scheurer, Stefan Schülke, Masako Toda
    Cells, 10, 7, 14 Jul. 2021, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal, Some β-mannans, including those in coffee bean and soy, contain a mannose backbone with β-(1→4) bonds. Such mannooligosaccharides could have immunological functions involving direct interaction with immune cells, in addition to acting as prebiotics. This study aimed at assessing the immunological function of mannooligosaccharides with β-(1→4) bond, and elucidating their mechanism of action using bone marrow-derived murine dendritic cells (BMDCs). When BMDCs were stimulated with the mannooligosaccharides, only β-Man-(1→4)-Man significantly induced production of cytokines that included IL-6, IL-10, TNF-α, and IFN-β, and enhanced CD4+ T-cell stimulatory capacity. Use of putative receptor inhibitors revealed the binding of β-Man-(1→4)-Man to TLR4/MD2 complex and involvement with the complement C3a receptor (C3aR) for BMDC activation. Interestingly, β-Man-(1→4)-Man prolonged the production of pro-inflammatory cytokines (IL-6 and TNF-α), but not of the IL-10 anti-inflammatory cytokine during extended culture of BMDCs, associated with high glucose consumption. The results suggest that β-Man-(1→4)-Man is an immunostimulatory molecule, and that the promotion of glycolysis could be involved in the production of pro-inflammatory cytokine in β-Man-(1→4)-Man-stimulated BMDCs. This study could contribute to development of immune-boosting functional foods and a novel vaccine adjuvant.
  • A model system for studying plant-microbe interactions under snow.
    Chikako Kuwabara, Kentaro Sasaki, Natsuki Umeki, Tamotsu Hoshino, Wataru Saburi, Hirokazu Matsui, Ryozo Imai
    Plant physiology, 185, 4, 1489, 1494, 02 Feb. 2021, [Peer-reviewed], [International Magazine]
    English, Scientific journal, A model plant–pathogen system using Arabidopsis and its natural snow mold pathogen Typhula ishikariensis demonstrated Arabidopsis plants develop disease resistance through cold acclimation.
  • Preliminary evaluation of colorimetric and HPLC-based methods for quantifying β-(1→4)-mannobiose in a crude material
    Kensuke Fukui, Wataru Saburi, Masahisa Ibuki, Kazunobu Tsumura, Haruhide Mori
    Food Science and Technology Research, 27, 2, 249, 257, Japanese Society for Food Science and Technology, 2021, [Peer-reviewed]
    Scientific journal
  • Efficient one-pot enzymatic synthesis of trehalose 6-phosphate using GH65 α-glucoside phosphorylases.
    Yodai Taguchi, Wataru Saburi, Ryozo Imai, Haruhide Mori
    Carbohydrate research, 488, 107902, 107902, Feb. 2020, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Trehalose 6-phosphate (Tre6P) is an important intermediate for trehalose biosynthesis. Recent researches have revealed that Tre6P is an endogenous signaling molecule that regulates plant development and stress responses. The necessity of Tre6P in physiological studies is expected to be increasing. To achieve the cost-effective production of Tre6P, a novel approach is required. In this study, we utilized trehalose 6-phosphate phosphorylase (TrePP) from Lactococcus lactis to produce Tre6P. In the reverse phosphorolysis by the TrePP, 91.9 mM Tre6P was produced from 100 mM β-glucose 1-phosphate (β-Glc1P) and 100 mM glucose 6-phosphate (Glc6P). The one-pot reaction of TrePP and maltose phosphorylase (MP) enabled production of 65 mM Tre6P from 100 mM maltose, 100 mM Glc6P, and 20 mM inorganic phosphate. Addition of β-phosphoglucomutase to this reaction produced Glc6P from β-Glc1P and thus reduced requirement of Glc6P as a starting material. Within the range of 20-469 mM inorganic phosphate tested, the 54 mM concentration yielded the highest amount of Tre6P (33 mM). Addition of yeast increased the yield because of its glucose consumption. Finally, from 100 mmol maltose and 60 mmol inorganic phosphate, we successfully achieved production of 37.5 mmol Tre6P in a one-pot reaction (100 mL), and 9.4 g Tre6P dipotassium salt was obtained.
  • Two binding proteins of the ABC transporter that confers growth of Bifidobacterium animalis subsp. lactis ATCC27673 on β-mannan possess distinct manno-oligosaccharide-binding profiles.
    M Ejby, A Guskov, M J Pichler, G C Zanten, E Schoof, W Saburi, D J Slotboom, M Abou Hachem
    Molecular microbiology, 112, 1, 114, 130, Jul. 2019, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Human gut bifidobacteria rely on ATP-binding cassette (ABC) transporters for oligosaccharide uptake. Multiple oligosaccharide-specific solute-binding protein (SBP) genes are occasionally associated with a single ABC transporter, but the significance of this multiplicity remains unclear. Here, we characterize BlMnBP1 and BlMnBP2, the two SBPs associated to the β-manno-oligosaccharide (MnOS) ABC transporter in Bifidobacterium animalis subsp. lactis. Despite similar overall specificity and preference to mannotriose (Kd ≈80 nM), affinity of BlMnBP1 is up to 2570-fold higher for disaccharides than BlMnBP2. Structural analysis revealed a substitution of an asparagine that recognizes the mannosyl at position 2 in BlMnBP1, by a glycine in BlMnBP2, which affects substrate affinity. Both substitution types occur in bifidobacterial SBPs, but BlMnBP1-like variants prevail in human gut isolates. B. animalis subsp. lactis ATCC27673 showed growth on gluco and galactomannans and was able to outcompete a mannan-degrading Bacteroides ovatus strain in co-cultures, attesting the efficiency of this ABC uptake system. By contrast, a strain that lacks this transporter failed to grow on mannan. This study highlights SBP diversification as a possible strategy to modulate oligosaccharide uptake preferences of bifidobacterial ABC-transporters during adaptation to specific ecological niches. Efficient metabolism of galactomannan by distinct bifidobacteria, merits evaluating this plant glycan as a potential prebiotic.
  • Biochemical characteristics of maltose phosphorylase MalE from Bacillus sp. AHU2001 and chemoenzymatic synthesis of oligosaccharides by the enzyme.
    Gao Y, Saburi W, Taguchi Y, Mori H
    Bioscience, biotechnology, and biochemistry, 83, 2097, 2109, Jul. 2019, [Peer-reviewed], [International Magazine]
  • Enzymatic characteristics of D-mannose 2-epimerase, a new member of the acylglucosamine 2-epimerase superfamily.
    Saburi W, Sato S, Hashiguchi S, Muto H, Iizuka T, Mori H
    Applied microbiology and biotechnology, Jun. 2019, [Peer-reviewed], [Lead author], [International Magazine]
  • Enzymatic production of xylooligosaccharides from red alga dulse (Palmaria sp.) wasted in Japan {IF:2.616]
    Y.Yamamoto, H.Kishimura, Y.Kinoshita, W.Saburi, Y.Kumagai, H.Yasui, T.Ojima
    Process Biochemistry, Apr. 2019, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • The rice ethylene response factor OsERF83 positively regulates disease resistance to Magnaporthe oryzae.
    Tezuka D, Kawamata A, Kato H, Saburi W, Mori H, Imai R
    Plant physiology and biochemistry : PPB, 135, 263, 271, Elsevier BV, Feb. 2019, [Peer-reviewed], [International Magazine]
    Scientific journal
  • Functional modulation of caecal fermentation and microbiota in rat by feeding bean husk as a dietary fibre supplement.
    Myint H, Kishi H, Iwahashi Y, Saburi W, Koike S, Kobayashi Y
    Beneficial microbes, 9, 6, 1, 12, Wageningen Academic Publishers, Sep. 2018, [Peer-reviewed], [International Magazine]
    Scientific journal, A feeding study using rats was conducted to evaluate the utility of lablab bean husk and soya bean husk as sources of potential prebiotic fibre. Twenty 5-week-old Sprague Dawley rats were divided into 4 groups and fed one of the following diets for 3 weeks: purified diet (AIN93 G) containing 5% cellulose (CEL), or the same diet in which cellulose was replaced by corn starch (STA), lablab bean husk (LBH), or soya bean husk (SBH). Rats were sacrificed at 8 weeks of age and caecal digesta were collected. Feed intake, body weight, anatomical parameters, and caecal ammonia level did not differ significantly among diets. Rats on LBH and SBH showed higher concentrations of caecal short-chain fatty acid and lactate than those on CEL. Rats on CEL, SBH, and LBH exhibited lower caecal indole and skatole levels. LBH yielded increased caecal abundance of Akkermansia muciniphila and Oscillibacter relatives, as demonstrated by either qPCR, MiSeq, or clone library analysis. SBH favoured the growth of lactobacilli as assessed by both qPCR and MiSeq, and favoured the growth of bifidobacteria as assessed by MiSeq. In comparison with STA, LBH and SBH yielded lower caecal abundance of bacteria related to Dorea massiliensis, as demonstrated by qPCR, MiSeq, and clone library analysis. Both types of bean husk were found to contain oligosaccharides that might selectively stimulate the growth of beneficial bacteria. Based on these results, the two species of bean husk tested are considered potentially functional for promoting the gut health of monogastric animals.
  • A Transposon Mutagenesis System for Bifidobacterium longum subsp. longum Based on an IS3 Family Insertion Sequence, ISBlo11.
    Mikiyasu Sakanaka, Shingo Nakakawaji, Shin Nakajima, Satoru Fukiya, Arisa Abe, Wataru Saburi, Haruhide Mori, Atsushi Yokota
    Applied and environmental microbiology, 84, 17, 01 Sep. 2018, [Peer-reviewed], [International Magazine]
    English, Scientific journal, Bifidobacteria are a major component of the intestinal microbiota in humans, particularly breast-fed infants. Therefore, elucidation of the mechanisms by which these bacteria colonize the intestine is desired. One approach is transposon mutagenesis, a technique currently attracting much attention because, in combination with next-generation sequencing, it enables exhaustive identification of genes that contribute to microbial fitness. We now describe a transposon mutagenesis system for Bifidobacterium longum subsp. longum 105-A (JCM 31944) based on ISBlo11, a native IS3 family insertion sequence. To build this system, xylose-inducible or constitutive bifidobacterial promoters were tested to drive the expression of full-length or a truncated form at the N terminus of the ISBlo11 transposase. An artificial transposon plasmid, pBFS12, in which ISBlo11 terminal inverted repeats are separated by a 3-bp spacer, was also constructed to mimic the transposition intermediate of IS3 elements. The introduction of this plasmid into a strain expressing transposase resulted in the insertion of the plasmid with an efficiency of >103 CFU/μg DNA. The plasmid targets random 3- to 4-bp sequences, but with a preference for noncoding regions. This mutagenesis system also worked at least in B. longum NCC2705. Characterization of a transposon insertion mutant revealed that a putative α-glucosidase mediates palatinose and trehalose assimilation, demonstrating the suitability of transposon mutagenesis for loss-of-function analysis. We anticipate that this approach will accelerate functional genomic studies of B. longum subsp. longumIMPORTANCE Several hundred species of bacteria colonize the mammalian intestine. However, the genes that enable such bacteria to colonize and thrive in the intestine remain largely unexplored. Transposon mutagenesis, combined with next-generation sequencing, is a promising tool to comprehensively identify these genes but has so far been applied only to a small number of intestinal bacterial species. In this study, a transposon mutagenesis system was established for Bifidobacterium longum subsp. longum, a representative health-promoting Bifidobacterium species. The system enables the identification of genes that promote colonization and survival in the intestine and should help illuminate the physiology of this species.
  • Function and structure of GH13_31 α-glucosidase with high α-(1→4)-glucosidic linkage specificity and transglucosylation activity.
    Auiewiriyanukul W, Saburi W, Kato K, Yao M, Mori H
    FEBS letters, 592, 13, 2268, 2281, Jul. 2018, [Peer-reviewed], [International Magazine]
  • Biochemical and structural characterization of Marinomonas mediterranea D-mannose isomerase Marme_2490 phylogenetically distant from known enzymes
    Wataru Saburi, Nongluck Jaito, Koji Kato, Yuka Tanaka, Min Yao, Haruhide Mori
    Biochimie, 144, 63, 73, Elsevier B.V., 01 Jan. 2018, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
    English, Scientific journal
  • Elucidation of the biosynthetic pathway of cis-jasmone in Lasiodiplodia theobromae
    Ryo Matsui, Naruki Amano, Kosaku Takahashi, Yodai Taguchi, Wataru Saburi, Hideharu Mori, Norio Kondo, Kazuhiko Matsuda, Hideyuki Matsuura
    SCIENTIFIC REPORTS, 7, 1, 6688, Jul. 2017, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Evaluation of acceptor selectivity of Lactococcus lactis ssp lactis trehalose 6-phosphate phosphorylase in the reverse phosphorolysis and synthesis of a new sugar phosphate
    Yodai Taguchi, Wataru Saburi, Ryozo Imai, Haruhide Mori
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 81, 8, 1512, 1519, 2017, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Functions, structures, and applications of cellobiose 2-epimerase and glycoside hydrolase family 130 mannoside phosphorylases
    Wataru Saburi
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 80, 7, 1294, 1305, Jul. 2016, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
    English
  • alpha-Glucosidases and alpha-1,4-glucan lyases: structures, functions, and physiological actions
    Masayuki Okuyama, Wataru Saburi, Haruhide Mori, Atsuo Kimura
    CELLULAR AND MOLECULAR LIFE SCIENCES, 73, 14, 2727, 2751, Jul. 2016, [Peer-reviewed], [Lead author], [International Magazine]
    English
  • The cold-induced defensin TAD1 confers resistance against snow mold and Fusarium head blight in transgenic wheat
    Kentaro Sasaki, Chikako Kuwabara, Natsuki Umeki, Mari Fujioka, Wataru Saburi, Hirokazu Matsui, Fumitaka Abe, Ryozo Imai
    JOURNAL OF BIOTECHNOLOGY, 228, 3, 7, Jun. 2016, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Purification and characterization of a chloride ion-dependent alpha-glucosidase from the midgut gland of Japanese scallop (Patinopecten yessoensis)
    Yasushi Masuda, Masayuki Okuyama, Takahisa Iizuka, Hiroyuki Nakai, Wataru Saburi, Taro Fukukawa, Janjira Maneesan, Takayoshi Tagami, Tetsushi Naraoka, Haruhide Mori, Atsuo Kimura
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 80, 3, 479, 485, Mar. 2016, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Structural insights into the difference in substrate recognition of two mannoside phosphorylases from two GH130 subfamilies
    Yuxin Ye, Wataru Saburi, Rei Odaka, Koji Kato, Naofumi Sakurai, Keisuke Komoda, Mamoru Nishimoto, Motomitsu Kitaoka, Haruhide Mori, Min Yao
    FEBS LETTERS, 590, 6, 828, 837, Mar. 2016, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Supplemental epilactose prevents metabolic disorders through uncoupling protein-1 induction in the skeletal muscle of mice fed high-fat diets
    Yuki Murakami, Teruyo Ojima-Kato, Wataru Saburi, Haruhide Mori, Hirokazu Matsui, Soichi Tanabe, Takuya Suzuki
    BRITISH JOURNAL OF NUTRITION, 114, 11, 1774, 1783, Dec. 2015, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Identification of rice Os4BGlu13 as a beta-glucosidase which hydrolyzes gibberellin A4 1-O-beta-D-glucosyl ester, in addition to tuberonic acid glucoside and salicylic acid derivative glucosides
    Yanling Hua, Watsamon Ekkhara, Sompong Sansenya, Chantragan Srisomsap, Sittiruk Roytrakul, Wataru Saburi, Ryosuke Takeda, Hideyuki Matsuura, Haruhide Mori, James R. Ketudat Cairns
    ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS, 583, 36, 46, Oct. 2015, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal
  • Functional reassignment of Cellvibrio vulgaris EpiA to cellobiose 2-epimerase and an evaluation of the biochemical functions of the 4-O-beta-d-mannosyl-d-glucose phosphorylase-like protein, UnkA
    Wataru Saburi, Yuka Tanaka, Hirohiko Muto, Sota Inoue, Rei Odaka, Mamoru Nishimoto, Motomitsu Kitaoka, Haruhide Mori
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 79, 6, 969, 977, Jun. 2015, [Peer-reviewed], [Lead author], [International Magazine]
    English, Scientific journal
  • Structural elements responsible for the glucosidic linkage-selectivity of a glycoside hydrolase family 13 exo-glucosidase
    Wataru Saburi, Hiroaki Rachi-Otsuka, Hironori Hondoh, Masayuki Okuyama, Haruhide Mori, Atsuo Kimura
    FEBS LETTERS, 589, 7, 865, 869, Mar. 2015, [Peer-reviewed], [Lead author], [International Magazine]
    English, Scientific journal
  • Structural insights into the catalytic reaction that is involved in the reorientation of Trp238 at the substrate-binding site in GH13 dextran glucosidase
    Momoko Kobayashi, Wataru Saburi, Daichi Nakatsuka, Hironori Hondoh, Koji Kato, Masayuki Okuyama, Haruhide Mori, Atsuo Kimura, Min Yao
    FEBS LETTERS, 589, 4, 484, 489, Feb. 2015, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Identity of the two dextran dextrinases produced by Gluconobacter oxydans ATCC 11894 and its localization change depending on the cell growth.
    Sadahiro J, Mori H, Saburi W, Okuyama M, Kimura A
    Biochem Biophys Res Commun, 456, 1, 500, 505, 2015, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Biochemical properties and substrate recognition mechanism of GH31 α-glucosidase from Bacillus sp. AHU 2001 with broad substrate specificity
    Wataru Saburi, Masayuki Okuyama, Yuya Kumagai, Atsuo Kimura, Haruhide Mori
    Biochimie, 108, 108, 140, 148, 2015, [Peer-reviewed], [Lead author], [International Magazine]
    English
  • Enhancement of hydrolytic activity of thermophilic alkalophilic alpha-amylase from Bacillus sp AAH-31 through optimization of amino acid residues surrounding the substrate binding site
    Naoya Tamamura, Wataru Saburi, Atsushi Mukai, Naoki Morimoto, Toshihiko Takehana, Seiji Koike, Hirokazu Matsui, Haruhide Mori
    BIOCHEMICAL ENGINEERING JOURNAL, 86, 8, 15, May 2014, [Peer-reviewed], [Lead author], [International Magazine]
    English, Scientific journal
  • Crystallization and preliminary X-ray crystallographic analysis of alpha-glucosidase HaG from Halomonas sp strain H11
    Xing Shen, Wataru Saburi, Zuo-Qi Gai, Keisuke Komoda, Jian Yu, Teruyo Ojima-Kato, Yusuke Kido, Hirokazu Matsui, Haruhide Mori, Min Yao
    ACTA CRYSTALLOGRAPHICA SECTION F-STRUCTURAL BIOLOGY COMMUNICATIONS, 70, Pt 4, 464, 466, Apr. 2014, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal
  • Structural Insights into the Epimerization of beta-1,4-Linked Oligosaccharides Catalyzed by Cellobiose 2-Epimerase, the Sole Enzyme Epimerizing Non-anomeric Hydroxyl Groups of Unmodified Sugars
    Takaaki Fujiwara, Wataru Saburi, Hirokazu Matsui, Haruhide Mori, Min Yao
    JOURNAL OF BIOLOGICAL CHEMISTRY, 289, 6, 3405, 3415, Feb. 2014, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Characterization of a thermophilic 4-O-beta-D-mannosyl-D-glucose phosphorylase from Rhodothermus marinus
    Nongluck Jaito, Wataru Saburi, Rei Odaka, Yusuke Kido, Ken Hamura, Mamoru Nishimoto, Motomitsu Kitaoka, Hirokazu Matsui, Haruhide Mori
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 78, 2, 263, 270, Feb. 2014, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Replacement of the Catalytic Nucleophile Aspartyl Residue of Dextran Glucosidase by Cysteine Sulfinate Enhances Transglycosylation Activity
    Wataru Saburi, Momoko Kobayashi, Haruhide Mori, Masayuki Okuyama, Atsuo Kimura
    JOURNAL OF BIOLOGICAL CHEMISTRY, 288, 44, 31670, 31677, Nov. 2013, [Peer-reviewed], [Lead author], [International Magazine]
    English, Scientific journal
  • Characterization of Ruminococcus albus cellodextrin phosphorylase and identification of a key phenylalanine residue for acceptor specificity and affinity to the phosphate group
    Tatsuya Sawano, Wataru Saburi, Ken Hamura, Hirokazu Matsui, Haruhide Mori
    FEBS Journal, 280, 18, 4463, 4473, Sep. 2013, [Peer-reviewed], [Lead author], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal
  • Modulation of Allosteric Regulation by E38K and G101N Mutations in the Potato Tuber ADP-glucose Pyrophosphorylase
    Shinji Wakuta, Yumi Shibata, Yumiko Yoshizaki, Wataru Saburi, Shigeki Hamada, Hiroyuki Ito, Seon-Kap Hwang, Thomas W. Okita, Hirokazu Matsui
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 77, 9, 1854, 1859, Sep. 2013, [Peer-reviewed], [Corresponding author], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal
  • A Thermophilic Alkalophilic alpha-Amylase from Bacillus sp AAH-31 Shows a Novel Domain Organization among Glycoside Hydrolase Family 13 Enzymes
    Wataru Saburi, Naoki Morimoto, Atsushi Mukai, Dae Hoon Kim, Toshihiko Takehana, Seiji Koike, Hirokazu Matsui, Haruhide Mori
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 77, 9, 1867, 1873, Sep. 2013, [Peer-reviewed], [Lead author], [International Magazine]
    English, Scientific journal
  • Identification of Rice beta-Glucosidase with High Hydrolytic Activity towards Salicylic Acid beta-D-Glucoside
    Nami Himeno, Wataru Saburi, Shinji Wakuta, Ryosuke Takeda, Hideyuki Matsuura, Kensuke Nabeta, Sompong Sansenya, James R. Ketudat Cairns, Haruhide Mori, Ryozo Imai, Hirokazu Matsui
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 77, 5, 934, 939, May 2013, [Peer-reviewed], [Lead author], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal
  • Crystal structure of Ruminococcus albus cellobiose 2-epimerase: Structural insights into epimerization of unmodified sugar
    Takaaki Fujiwara, Wataru Saburi, Sota Inoue, Haruhide Mori, Hirokazu Matsui, Isao Tanaka, Min Yao
    FEBS LETTERS, 587, 7, 840, 846, Apr. 2013, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Identification and Characterization of Cellobiose 2-Epimerases from Various Aerobes
    Teruyo Ojima, Wataru Saburi, Takeshi Yamamoto, Haruhide Mori, Hirokazu Matsui
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 77, 1, 189, 193, Jan. 2013, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Modulation of acceptor specificity of Ruminococcus albus cellobiose phosphorylase through site-directed mutagenesis
    Ken Hamura, Wataru Saburi, Hirokazu Matsui, Haruhide Mori
    Carbohydrate Research, 379, 21, 25, Elsevier Ltd, 2013, [Peer-reviewed], [Lead author], [International Magazine]
    English, Scientific journal
  • COLD SHOCK DOMAIN PROTEIN 3 is involved in salt and drought stress tolerance in Arabidopsis
    Myung-Hee Kim, Shunya Sato, Kentaro Sasaki, Wataru Saburi, Hirokazu Matsui, Ryozo Imai
    FEBS OPEN BIO, 3, 438, 442, 2013, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Metabolic Mechanism of Mannan in a Ruminal Bacterium, Ruminococcus albus, Involving Two Mannoside Phosphorylases and Cellobiose 2-Epimerase DISCOVERY OF A NEW CARBOHYDRATE PHOSPHORYLASE, beta-1,4-MANNOOLIGOSACCHARIDE PHOSPHORYLASE
    Ryosuke Kawahara, Wataru Saburi, Rei Odaka, Hidenori Taguchi, Shigeaki Ito, Haruhide Mori, Hirokazu Matsui
    JOURNAL OF BIOLOGICAL CHEMISTRY, 287, 50, 42389, 42399, Dec. 2012, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
    English, Scientific journal
  • Bacteroides thetaiotaomicron VPI-5482 glycoside hydrolase family 66 homolog catalyzes dextranolytic and cyclization reactions
    Young-Min Kim, Eiji Yamamoto, Min-Sun Kang, Hiroyuki Nakai, Wataru Saburi, Masayuki Okuyama, Haruhide Mori, Kazumi Funane, Mitsuru Momma, Zui Fujimoto, Mikihiko Kobayashi, Doman Kim, Atsuo Kimura
    FEBS JOURNAL, 279, 17, 3185, 3191, Sep. 2012, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Immobilization of a Thermostable Cellobiose 2-Epimerase from Rhodothermus marinus JCM9785 and Continuous Production of Epilactose
    Hiroki Sato, Wataru Saburi, Teruyo Ojima, Hidenori Taguchi, Haruhide Mori, Hirokazu Matsui
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 76, 8, 1584, 1587, Aug. 2012, [Peer-reviewed], [Lead author, Corresponding author], [International Magazine]
    English, Scientific journal
  • Purification and Characterization of a Liquefying alpha-Amylase from Alkalophilic Thermophilic Bacillus sp AAH-31
    Dae Hoon Kim, Naoki Morimoto, Wataru Saburi, Atsushi Mukai, Koji Imoto, Toshihiko Takehana, Seiji Koike, Haruhide Mori, Hirokazu Matsui
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 76, 7, 1378, 1383, Jul. 2012, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Novel Dextranase Catalyzing Cycloisomaltooligosaccharide Formation and Identification of Catalytic Amino Acids and Their Functions Using Chemical Rescue Approach
    Young-Min Kim, Yoshiaki Kiso, Tomoe Muraki, Min-Sun Kang, Hiroyuki Nakai, Wataru Saburi, Weeranuch Lang, Hee-Kwon Kang, Masayuki Okuyama, Haruhide Mori, Ryuichiro Suzuki, Kazumi Funane, Nobuhiro Suzuki, Mitsuru Momma, Zui Fujimoto, Tetsuya Oguma, Mikihiko Kobayashi, Doman Kim, Atsuo Kimura
    JOURNAL OF BIOLOGICAL CHEMISTRY, 287, 24, 19927, 19935, Jun. 2012, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal
  • alpha-Glucosylated 6-gingerol: chemoenzymatic synthesis using alpha-glucosidase from Halomonas sp H11, and its physical properties
    Teruyo Ojima, Kenta Aizawa, Wataru Saburi, Takeshi Yamamoto
    CARBOHYDRATE RESEARCH, 354, 59, 64, Jun. 2012, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • A Novel Metabolic Pathway for Glucose Production Mediated by alpha-Glucosidase-catalyzed Conversion of 1,5-Anhydrofructose
    Young-Min Kim, Wataru Saburi, Shukun Yu, Hiroyuki Nakai, Janjira Maneesan, Min-Sun Kang, Seiya Chiba, Doman Kim, Masayuki Okuyama, Haruhide Mori, Atsuo Kimura
    JOURNAL OF BIOLOGICAL CHEMISTRY, 287, 27, 22441, 22444, Jun. 2012, [Peer-reviewed], [Lead author], ［Internationally co-authored］, [International Magazine]
    English, Scientific journal
  • Enzymatic Characteristics of Cellobiose Phosphorylase from Ruminococcus albus NE1 and Kinetic Mechanism of Unusual Substrate Inhibition in Reverse Phosphorolysis
    Ken Hamura, Wataru Saburi, Shotaro Abe, Naoki Morimoto, Hidenori Taguchi, Haruhide Mori, Hirokazu Matsui
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 76, 4, 812, 818, Apr. 2012, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Characterization of Halomonas sp Strain H11 alpha-Glucosidase Activated by Monovalent Cations and Its Application for Efficient Synthesis of alpha-D-Glucosylglycerol
    Teruyo Ojima, Wataru Saburi, Takeshi Yamamoto, Toshiaki Kudo
    APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 78, 6, 1836, 1845, Mar. 2012, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Biochemical Characterization of a Thermophilic Cellobiose 2-Epimerase from a Thermohalophilic Bacterium, Rhodothermus marinus JCM9785
    Teruyo Ojima, Wataru Saburi, Hiroki Sato, Takeshi Yamamoto, Haruhide Mori, Hirokazu Matsui
    BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 75, 11, 2162, 2168, Nov. 2011, [Peer-reviewed]
    English, Scientific journal
  • OsJAR1 and OsJAR2 are jasmonyl-L-isoleucine synthases involved in wound- and pathogen-induced jasmonic acid signalling
    Shinji Wakuta, Erika Suzuki, Wataru Saburi, Hideyuki Matsuura, Kensuke Nabeta, Ryozo Imai, Hirokazu Matsui
    BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 409, 4, 634, 639, Jun. 2011, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Ingestion of epilactose, a non-digestible saccharide, improves postgastrectomy osteopenia and anemia in rats through the promotion of intestinal mineral absorption. - Comparative analyses of two non-digestible saccharides, epilactose and fructooligosaccha
    Taguchi Hidenori, Suzuki Takuya, Nishimukai Megumi, Yokoshima Satoru, Ojima Teruyo, Yamamoto Takeshi, Saburi Wataru, Hara Hiroshi, Kaneda Isamu, Onodera Shuichi, Shiomi Norio, Matsui Hirokazu
    Journal of Applied Glycoscience Supplement, 2011, 0, 74, 74, The Japanese Society of Applied Glycoscience, 2011, [Peer-reviewed], [Domestic magazines]
    Scientific journal
  • Ingestion of Epilactose, a Non-digestible Disaccharide, Improves Postgastrectomy Osteopenia and Anemia in Rats through the Promotion of Intestinal Calcium and Iron Absorption
    Takuya Suzuki, Megumi Nishimukai, Aki Shinoki, Hidenori Taguchi, Satoru Fukiya, Atsushi Yokota, Wataru Saburi, Takeshi Yamamoto, Hiroshi Hara, Hirokazu Matsui
    JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, 58, 19, 10787, 10792, Oct. 2010, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Ingestion of epilactose, a non-digestible saccharide, prevents gastrectomy-induced calcium malabsorption, iron malabsorption, osteopenia, and anemia in rats.
    Suzuki Takuya, Nishimukai Megumi, Taguchi Hidenori, Hamada Shigeki, Saburi Wataru, Yamamoto Takeshi, Ito Susumu, Hara Hiroshi, Matsui Hirokazu
    Journal of Applied Glycoscience Supplement, 2010, 90, 90, The Japanese Society of Applied Glycoscience, 2010
    Japanese
  • Alteration of transglucosylation/hydrolysis ratio of Streptococcus mutans dextran glucosidase (2)
    Nakatsuka Daichi, Hondoh Hironori, Otsuka Hiroaki, Saburi Wataru, Mori Haruhide, Okuyama Masayuki, Kimura Atsuo
    Journal of Applied Glycoscience Supplement, 2009, 34, 34, The Japanese Society of Applied Glycoscience, 2009
    Japanese
  • Structure-function relationship of substrate length specificity of dextran glucosidase from Streptococcus mutans
    Wataru Saburi, Hironori Hondoh, Young-Min Kim, Haruhide Mori, Masayuki Okuyama, Atsuo Kimura
    BIOLOGIA, 63, 6, 1000, 1005, Dec. 2008, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Gene cloning and enzymatic characteristics of a novel gamma-cyclodextrin-specific cyclodextrinase from alkalophilic Bacillus clarkii 7364.
    Nakagawa Y, Saburi W, Takada M, Hatada Y, Horikoshi K
    Biochimica et biophysica acta, 1784, 12, 2004, 2011, Dec. 2008, [Peer-reviewed], [International Magazine]
  • Molecular Mechanism of α-glucosidase
    Masayuki Okuyama, Haruhide Mori, Hironori Hondoh, Hiroyuki Nakai, Wataru Saburi, Min Sung Kang, Young Min Kim, Mamoru Nishimoto, Jintanart Wongchawalit, Takeshi Yamamoto, Mee Son, Jin Ha Lee, San San Mar, Kenji Fukuda, Seiya Chiba, Atsuo Kimura
    Carbohydrate-Active Enzymes: Structure, Function and Applications, 64, 76, Sep. 2008, [Peer-reviewed], [International Magazine]
    In book
  • Substrate recognition mechanism of alpha-1,6-glucosidic linkage hydrolyzing enzyme, dextran glucosidase from Streptococcus mutans
    Hironori Hondoh, Wataru Saburi, Haruhide Mori, Masayuki Okuyama, Toshitaka Nakada, Yoshiki Matsuura, Atsuo Kimura
    JOURNAL OF MOLECULAR BIOLOGY, 378, 4, 913, 922, May 2008, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Crystallization and preliminary X-ray analysis of Streptococcus mutans dextran glucosidase
    Wataru Saburi, Hironori Hondoh, Hideaki Unno, Masayuki Okuyama, Haruhide Mori, Toshitaka Nakada, Yoshiki Matsuura, Atsuo Kimura
    ACTA CRYSTALLOGRAPHICA SECTION F-STRUCTURAL BIOLOGY AND CRYSTALLIZATION COMMUNICATIONS, 63, Pt 9, 774, 776, Sep. 2007, [Peer-reviewed], [Lead author], [International Magazine]
    English, Scientific journal
  • Structural elements in dextran glucosidase responsible for high specificity to long chain substrate
    Wataru Saburi, Haruhide Mori, Saori Saito, Masayuki Okuyama, Atsuo Kimura
    BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS, 1764, 4, 688, 698, Apr. 2006, [Peer-reviewed], [Lead author], [International Magazine]
    English, Scientific journal
  • Enzymatic synthesis of alkyl α-2-deoxyglucosides by alkyl alcohol resistant α-glucosidase from Aspergillus niger
    Young-Min Kim, Masayuki Okuyama, Haruhide Mori, Hiroyuki Nakai, Wataru Saburi, Seiya Chiba, Atsuo Kimura
    Tetrahedron Asymmetry, 16, 2, 403, 409, 24 Jan. 2005, [Peer-reviewed], [International Magazine]
    English, Scientific journal
  • Molecular analysis of α-glucosidase belonging to GH-family 31
    Nakai H, Okuyama M, Kim YM, Saburi W, Wongchawalit J, Mori H, Chiba S, Kimura A
    Biologia, Bratislava, 60, 131, 135, 2005, [Peer-reviewed], [International Magazine]
    English
  • Isolation and characterization of cDNA encoding P-19.5 protein accumulated preferentially at early stage of carrot somatic embryogenesis
    Takuma Sano, Mamoru Nishimoto, Wataru Saburi, Atsuo Kimura, Hiroshi Yasuda, Masahiro Uchibatake, Takuji Ohwada, Hiroshi Masuda
    Plant Science, 167, 6, 1211, 1217, Dec. 2004, [Peer-reviewed], [International Magazine]
    English, Scientific journal

Other Activities and Achievements

Affiliated academic society

  • THE JAPANESE SOCIETY OF APPLIED GLYCOSCIENCE　　　　　　　　　　　　　　　
  • JAPAN SOCIETY FOR BIOSCIENCE, BIOTECHNOLOGY, AND AGROCHEMISTRY　　　　　　　　　　　　　　　

Research Themes

  • ゲノムデザインと自由な書き換えによる高収量コムギの創出
    科学研究費助成事業
    09 Jul. 2021 - 31 Mar. 2024
    今井 亮三, 佐分利 亘
    日本学術振興会, 挑戦的研究(萌芽), 国立研究開発法人農業・食品産業技術総合研究機構, 21K19127
  • Molecular basis and functional modulation of carbohydrate epimerases and isomerases useful for carbohydrate conversion
    Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    01 Apr. 2021 - 31 Mar. 2024
    佐分利 亘
    糖質の高度利用には，希少糖質の効率合成法が必要である．本研究では，微生物の多様な糖質代謝を支える異性化酵素の中でも，セロビオース2-エピメラーゼやマンノースイソメラーゼなど様々な糖質異性化酵素を含む酵素群に注目し，反応特異性を制御する機構の解明と高活性変異酵素の開発を目的とした．セロビオース2-エピメラーぜの中にはエピメラーゼ活性のみを示す酵素 (1機能CE) とエピメラーゼ活性に加えてイソメラーゼ活性を示す酵素 (2機能CE) が存在するが，この特異性の違いを説明する構造は明らかではなかった．そこで，1機能CEと2機能CEの間で構造領域を入れ換えた一連のキメラ酵素を作成した．具体的には，(α/α)6バレルの触媒ドメインを構成するαヘリックス1と2，3と4，5と6，7と8，9と10，11と12について，1機能酵素の構造を2機能酵素に移植した．これら6つのキメラ酵素のうち，最初の3つの変異酵素は活性型酵素として得られた．この機能について解析を進めている．
    マンノースエピメラーゼ (ME酵素) については高活性変異酵素の取得のため，ハイスループットスクリーニング系を検討した．本スクリーニング系では，マンノーストランスポーター遺伝子を欠失させることでマンノース資化性を失われた大腸菌を用い，この細胞表層にME酵素を発現させることでマンノース資化性の回復，また，活性に応じた生育速度の増加により高活性変異酵素をスクリーニングすることを計画した．マンノーストランスポーターを構成する3タンパク質全ての遺伝子を欠失させることでマンノース資化性を完全に失わせることができた．この大腸菌変異株をホストとし，氷核タンパク質のNドメインを付加したME酵素を発現させると，ME酵素は外膜画分に生産され，マンノース資化性の回復が確認された．この系を利用して高活性変異酵素をスクリーニングする予定である．
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 21K05388
  • Analysis of immunological properties of mannose-based molecules and its action mechanisms.
    Grants-in-Aid for Scientific Research
    01 Apr. 2019 - 31 Mar. 2022
    Toda Masako
    The aim of this study was to identify immunological function of mannose-based molecules and its action mechanisms. Among α-mannooligosaccharides, long chain molecules such as α-Man-(1→6)-Man4 inhibited lipopolysaccharide (LPS)-stimulated activation of bone marrow derived murine dendritic cells (BMDC). In contrast, among β-mannooligosaccharides, β-Man-(1→4)-Man activated BMDC via engagement of toll-like receptor 4. We also found that α-mannan from yeast promotes anti-inflammatory responses (e.g., IL-10 production) in BMDC when it was stimulated with LPS. Metabolome analysis showed that α-mannan altered levels of many metabolites in BMDC, e.g., an increased level of lactic acid, the final product of glycolysis, and a reduced level of succinic acid, an inflammatory metabolite of TCA cycle. The results suggest that α-mannan induces reprogram of cellular metabolism and thereby promotes anti-inflammatory response in BMDC.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Tohoku University, 19H02902
  • Utilization of enzymes for production of a variety of carbohydrates
    Grants-in-Aid for Scientific Research
    01 Apr. 2018 - 31 Mar. 2021
    MORI Haruhide
    To develop the enzymatic production of carbohydrates, some enzymes were investigated in this study. As glycosyltransferases using sugar nucleotides as glycosyl donor, SS-enzyme and GS-enzyme were used. New disaccharides were produced using the SS-enzyme, in one-pot reaction with sucrose. The SS-enzyme was engineered for phosphorylated products. A new type of GS-enzyme was found. As transglycosylases, enzymes producing useful oligosaccharides and cyclic oligosaccharides were analyzed. Functions of the domains of the multi-domain structure, residues involved in the acceptor binding and determining their product preference were clarified.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 18H02133
  • Carbohydrate conversion by novel bacterial carbohydrate epimerases
    Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    01 Apr. 2018 - 31 Mar. 2021
    Saburi Wataru
    Carbohydrates with various structures have a variety of excellent functions, but kind of carbohydrates, which are abundantly present, is extremely limited. Therefore, it is necessary to establish the enzymatic synthesis technology using abundant carbohydrate resources for the utilization of useful rare carbohydrates. In this study, we clarified the functions of mannose 2-epimerase (ME) homologs from several strains, such as Dyadobacter fermentans, in addition to the originally discovered enzyme from Runella slithyformis. In addition, a cellobiose 2-epimerase with broad specificity that acts on monosaccharides such as glucose and galactose in addition to β1-4 disaccharides was discovered through functional analysis of ME homologs.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 18K05382
  • Molecular mechanism of activation of signal compounds regulating resistance against pathogen in plants
    Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    21 Oct. 2015 - 31 Mar. 2018
    Hirokazu Matsui
    In plants, physiologically active compounds are inactivated by glycosylation and activated by hydrolysis of glycosides. In this study, rice beta-glucosidase TAGG2, which has high activity towards both tuberonic acid (TA) beta-glucoside and salicylic acid beta-glucoside (SAG), was biochemically and physiologically characterized. Important amino acid residues involved in recognition of SAG were determined through site-directed mutagenesis, and localization of TAGG2 to apoplast was confirmed using transgenic rice expressing a fusion protein of GFP and TAGG2. In transgenic rice expressing TAGG2, over-accumulation of TA was observed but SA level was not changed significantly. Blast infection analysis suggested overexpression of the TAGG2 gene negatively regulated the resistance against pathogens. Homologous enzymes in Arabidopsis had high activity towards oligosaccharide substrates such as laminarioligosaccharide rather than SAG.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 15K07379
  • Enzymatic synthesis of oligosaccharides, polysaccharides, and glycosides
    Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    01 Apr. 2015 - 31 Mar. 2018
    Mori Haruhide
    Carbohydrate includes a wide variety of molecules because of the diversity of constituent monosaccharides, linkages, and degrees of polymerization. They are highly expected to contain functional compounds useful for human life. Therefore, various synthetic methods are required for synthesis of various saccharides. In this study, enzymatic conversion from highly abundant carbohydrates in nature was established with two types of enzymes: glycoside synthase and glycosyl transferase. In the method with synthase, sugar nucleotides, substrates for glycoside synthases, were provided from sucrose, and disaccharides were efficiently produced through the one-pot reactions. A new group of glycosyl transferases were found. The enzymes in it acted on maltooligosaccharides and catalyzed glucosyl transfer reactions.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 15H04484
  • Molecular basis for oligosaccharide epimerases and their related enzymes.
    Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)
    01 Apr. 2014 - 31 Mar. 2016
    SABURI Wataru
    Cellobiose 2-epimerase (CE) epimerizes the reducing end glucose residue of beta1-4 disaccharides to mannose residue. It shares the catalytic domain and site structures with other monosaccharide isomerases/epimerases. In this study, structure-function relationship of these enzymes was analyzed. Important amino acid residues for high selectivity for disaccharides in Rhodothermus marines CE were determined through site-directed mutation. Slight isomerization activity was observed in R. marines CE, and important structure for isomerase activity was determined based on the comparison of the structures between R. marines and Cardicellulosiruptor saccharolyticus CEs. A novel enzyme acting on mannose was found from function unknown proteins.
    Japan Society for the Promotion of Science, Grant-in-Aid for Young Scientists (B), Hokkaido University, 26850059
  • オリゴ糖異性化酵素とその類縁酵素の構造基盤の解明　　　　　　　　　　　　　　　
    科学研究費補助金 若手研究(B)
    Apr. 2014 - Mar. 2016
    佐分利 亘
    文部科学省, Principal investigator, Competitive research funding
  • Identification and functional analysis of novel metabolizing enzymes of plant hormones
    Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    01 Apr. 2012 - 31 Mar. 2015
    MATSUI Hirokazu, SABURI Wataru, MATSUURA Hideyuki
    Jasmonate (JA) is a plant hormone regulating abiotic and biotic stress responses and growth. In this study, we analyzed the physiological and biochemical functions of CYP94D1, CYP94D2, and ILL6 proteins, which were predicted to inactivate the JA signal. In the analysis of mutant plants with higher and lower expression levels of CYP94D1 than wild type plant, we observed phenotypic differences. The transgenic plants lucking CYP94D1 showed higher resistance to external JA. The overexpressing plants of CYP94D1 accumulate higher level of tuberonic acid glucoside than wild type.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 24580134
  • オリゴ糖異性化酵素ならびに類縁酵素群の機能解明と有用糖質の効率合成への応用展開　　　　　　　　　　　　　　　
    奨励研究助成
    Apr. 2014 - Mar. 2015
    佐分利 亘
    野田産業科学研究所, Principal investigator, Competitive research funding
  • Molecular analysis of two novel carbohydrate phosphorylases
    Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)
    01 Apr. 2012 - 31 Mar. 2014
    SABURI Wataru
    A ruminal anaerobic baceteium, Ruminococcus albus, has two mannosylglucose phosphorylase isozymes (Type-I and Type-II), phosphorolyzing mannosylglucose to alpha-mannose 1-phosphate and glucose. Anyalysis of substrate specificity revealed that Type-I was specific to mannosylglucose, but Type-II had higher activity to mannooligosaccharide than mannosylglucose. These enzymes showed different acceptor substrate specificity in the synthetic reaction: Type-I enzyme showed synthetic activity to 6-OH glucose derivatives unlike in contrast to Type-II, which was completely inert to these substrates. Asp129 of Type-I enzyme was determined to be catalytic amino acid residue based on sequence comparison and site-directed mutagenesis analysis. Ile212 of Type-I enzyme was important for recognition of 6-OH glucose derivatives as acceptor substrates in the synthetic reaction (reverse reaction).
    Japan Society for the Promotion of Science, Grant-in-Aid for Young Scientists (B), Hokkaido University, 24780091
  • プレバイオティクスとして機能するエピラクトースの実用的合成法の開発　　　　　　　　　　　　　　　
    A-STEP 研究成果最適展開支援プログラム 第1回【FS】 探索タイプ
    Aug. 2013 - Mar. 2014
    佐分利 亘
    科学技術振興機構, Principal investigator, Competitive research funding
  • 2つの新規な糖質ホスホリラーゼの分子解析　　　　　　　　　　　　　　　
    科学研究費補助金 若手研究(B)
    Apr. 2012 - Mar. 2014
    佐分利 亘
    文部科学省, Principal investigator, Competitive research funding
  • プレバイオティクスの革新的酵素合成技術の開発　　　　　　　　　　　　　　　
    研究開発助成事業」(フードイノベーション創造支援事業 研究シーズ発掘補助金)
    Aug. 2012 - Mar. 2013
    佐分利 亘
    ノーステック財団, Principal investigator, Competitive research funding
  • バイオリアクターを利用したエピラクトースの効率的合成法の開発　　　　　　　　　　　　　　　
    「研究開発助成事業」(若手研究人材育成事業 Talent補助金)
    Sep. 2011 - Mar. 2012
    佐分利 亘
    ノーステック財団, Principal investigator, Competitive research funding
  • ルーメン細菌によるヘミセルロース分解の分子機構の解析　　　　　　　　　　　　　　　
    研究助成 (奨励助成)
    Apr. 2011 - Mar. 2012
    佐分利 亘
    公益財団法人秋山記念生命科学振興財団, Principal investigator, Competitive research funding

Industrial Property Rights