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Carbohydrate Research

Chiaki Matsuzaki, Chikahiro Takagaki, Yusuke Tomabechi, Lennart S Forsberg, Christian Heiss, Parastoo Azadi, Kenji Matsumoto, Toshihiko Katoh, Koji Hosomi, Jun Kunisawa, Kenji Yamamoto, Keiko Hisa
The exopolysaccharide (EPS) produced by probiotic Leuconostoc mesenteroides subsp. mesenteroides strain NTM048 has been reported to be an immunostimulant that enhances mucosal IgA production. In this study, we found that intranasal administration of mice with the EPS and an antigen (ovalbumin) resulted in secretion of antigen-specific IgA and IgG in the airway mucosa and the serum, suggesting that the EPS has the adjuvant activity for use with mucosal vaccination. Methylation analysis coupled to GC-MS, and 1D and 2D NMR spectroscopy revealed that 94% of the EPS consists of an α-(1 → 6) glucan containing 4% of 1→3-linked α-glucose branches...
June 15, 2017: Carbohydrate Research
Evgeny Vinogradov, Annie Aubry, Susan M Logan
Cell surface polysaccharides produced by C. perfringens ATCC 13124 were analyzed using NMR, chemical and immunological methods. Two distinct polymers were identified. The more abundant PS1 had a structure based on a polymer of β-mannosamine with a number of modifications, including varying levels of substitution at O-6 with PEtN, N-acetylation, and different linkages between monosaccharides. The shortest variant of PS1 represented a lipoteichoic acid. It contained only 1-4-linkages between ManNAc residues, minor branching α-Ribf, and glucosyl-glycerol at the reducing end, which was acylated with linear saturated fatty acids C16, C18, and C20 (dominant)...
June 15, 2017: Carbohydrate Research
Kornelia Skarbek, Iwona Gabriel, Piotr Szweda, Marek Wojciechowski, Muna A Khan, Boris Görke, Sławomir Milewski, Maria J Milewska
6-Sulfo-6-deoxy-D-glucosamine (GlcN6S), 6-sulfo-6-deoxy-D-glucosaminitol (ADGS) and their N-acetyl and methyl ester derivatives have been synthesized and tested as inhibitors of enzymes catalyzing reactions of the UDP-GlcNAc pathway in bacteria and yeasts. GlcN6S and ADGS at micromolar concentrations inhibited glucosamine-6-phosphate (GlcN6P) synthase of microbial origin. The former was also inhibitory towards fungal GlcN6P N-acetyl transferase, but at millimolar concentrations. Both compounds and their N-acetyl derivatives exhibited antimicrobial in vitro activity, with MICs in the 0...
June 12, 2017: Carbohydrate Research
Walaa A El-Kashak, Abdelsamed I Elshamy, Tarik A Mohamed, Abd El-Nasser G El Gendy, Ibrahim A Saleh, Akemi Umeyama
A new 8-ionized hydroxylated 9,10-anthraquinone namely, 1-hydroxy-3-methyl-9,10-anthraquinone-6-O-β-D-glucopyranoside-8-olate (Rumpictuside A, 1) along with five known flavonoids, apigenin 7-O-β-D-glucoside (2), vitexin (3), quercetin 3-O-β-D-glucouronide (4), orientin (5), and isorientin (6) were isolated from Rumex pictus. The structures of isolated compounds were identified by the extensive spectroscopic techniques such as, UV, FT-IR, 1D, 2D NMR and HR-FAB-ESI-MS. The ionized hydroxyl group in the new anthraquinone (1) was rarely found for anthraquinone glycosides isolated from natural sources...
June 9, 2017: Carbohydrate Research
Luis Morales-Quintana, Carolina Faúndez, Raúl Herrera, Vasni Zavaleta, María Cristina Ravanal, Jaime Eyzaguirre, María Alejandra Moya-León
The fungus Penicillium purpurogenum degrades plant cell walls by the action of cellulolytic, xylanolytic and pectinolytic enzymes. The α-D-galactosidase is one of the enzymes which may act on pectin degradation. This enzyme has several biotechnological and medical applications. The aim of this work was to better understand the molecular mechanism of α-D-galactosidase from P. purpurogenum (GALP1). For this purpose, a gene coding for the enzyme was identified from the fungal genome and heterologously expressed in Pichia pastoris...
June 9, 2017: Carbohydrate Research
Evelina L Zdorovenko, Alessio Cimmino, Guido Marchi, Alexander S Shashkov, Mario Fiori, Yuriy A Knirel, Antonio Evidente
An O-specific polysaccharide (OPS) was isolated from the lipopolysaccharide of Pseudomonas mediterranea strain C5P1rad1, the causal agents of tomato pith necrosis and Chrysanthemum stem rot, and studied by one- and two-dimensional (1)H and (13)C NMR spectroscopy. The following structure of the trisaccharide repeating unit of the OPS was established, which, to our knowledge, is unique among the known bacterial polysaccharide structures: →4)-β-d-ManpNAc3NAcA-(1 → 4)-β-d-ManpNAc3NAcA-(1 → 3)-α-d-QuipNAc4NAc-(1→ where QuiNAc4NAc and ManNAc3NAcA indicate 2,4-diacetamido-2,4,6-trideoxyglucose and 2,3-diacetamido-2,3-dideoxymannuronic acid, respectively...
June 1, 2017: Carbohydrate Research
Lei Zhang, Cian Mc Carthy, Xiangming Zhu
Synthesis of a glucosylated α-S-galactosylceramide (1), a potential immunostimulant, was achieved starting from D-galactose. Both O- and S-glycosidic linkages were constructed in highly stereoselective way, and the synthetic strategy could be extended to the synthesis of other α-S-GalCer analogues.
June 1, 2017: Carbohydrate Research
Tatsuo Okauchi, Shuya Nakamura, Kouta Tsubaki, Momoko Asakawa, Mitsuru Kitamura
Phosphatidylinositol phosphate (PIP) synthetase is a promising target for the development of new anti-mycobacterium compounds. We previously reported that myo-inositol 1-methylenephosphonate showed inhibitory activity against PIP synthetase. Herein, we report the synthesis of unprotected myo-inositol 4-methylenephosphonate, a constitutional isomer of myo-inositol 1-methylenephosphonate and found that the stereoselective hydrogenation of vinylphosphonate proceeded via Rh catalysis.
May 29, 2017: Carbohydrate Research
Immanuel Sanka, Eko Agus Suyono, Parvez Alam
Diatoms secrete extracellular polymeric substances (EPS), or mucilage, around the cell wall that may serve to aid in motility and form a discrete layer that may help maintain thicker layers of EPS that have a greater role in adhesion. Mucilage molecules adhere to the diatom frustules, which are biosilica skeletons that develop from the diatom cell walls. Here, molecular dynamics methods were used to determine the characteristics of mucilage molecules as a function of pore size; notably 1,4-α-D-galacturonic acid, 1,4-β-glucuronic acid and 1,4-β-D-mannuronic acid...
May 26, 2017: Carbohydrate Research
Alexander S Shashkov, Bin Liu, Johanna J Kenyon, Anastasiya V Popova, Mikhail M Shneider, Sof'ya N Senchenkova, Nikolay P Arbatsky, Konstantin A Miroshnikov, Lei Wang, Yuriy A Knirel
Capsular polysaccharides were isolated from A. baumannii LUH5535 (K35 CPS) and LUH5554 (K15 CPS) and studied by 1D and 2D (1)H and (13)C NMR spectroscopy. The CPSs were found to consist of linear tetrasaccharide repeats (K units) containing 2-acetamido-2-deoxy-d-galacturonic acid (K35) or 2,3-diacetamido-2,3-deoxy-d-glucuronic acid (K15) and 2,4-diacetamido-2,4,6-trideoxy-d-glucose (both CPSs). The K35 unit includes three O-acetyl groups on different GalNAcA residues. A. baumannii LUH5535 and LUH5554 carry the KL35 and KL15 gene clusters, respectively, and putatively assigned functions of genes in these clusters were consistent with the CPS structures established...
May 25, 2017: Carbohydrate Research
Toshihiro Osada, Megumi Maeda, Chinatsu Tanabe, Kaori Furuta, Christopher J Vavricka, Eiji Sasaki, Mitsuhiro Okano, Yoshinobu Kimura
Cha o 3 is a newly found glycosylated allergen from Chamaecyparis obtusa (Japanese cypress) pollen. The deduced amino acid sequence of Cha o 3 indicates that this glycoallergen contains a cellulase domain and a number of putative N-glycosylation sites. However, the structures of N -glycans linked to Cha o 3 remain to be determined. In this study, therefore, we analyzed the glycoform of Cha o 3 and found that this glycoallergen carries exclusively plant complex-type N-glycans; major structures were GlcNAc2Man3Xyl1Fuc1GlcNAc2 (39%), Gal1Fuc1GlcNAc2Man3Xyl1Fuc1GlcNAc2 (14%), and Gal2Fuc2GlcNAc2Man3Xyl1Fuc1GlcNAc2 (25%)...
May 24, 2017: Carbohydrate Research
Hongliang Zhang, Hengtao Wang, Qiulong Xu, Rui Lu, Yunhua Cao, Zhefeng Wang, Pingping Tang, Feng Lin, Yingxia Li
The hexa-fructopyranoside was synthesized with N-phenyltrifluoroacetimidate glycosylation. The synthesis was achieved by regioselective glycosylation on the 1-OH of fructopyranosyl acceptor. Fructosyl oligosaccharides were elongated with β-(2 → 1)-difructopyranosyl unit in every two steps, without any further protection/deprotection step. This work proved N-phenyltrifluoroacetimidate glycosylation a practical method for oligo-fructopyranoside synthesis.
May 22, 2017: Carbohydrate Research
Elena N Sigida, Yuliya P Fedonenko, Alexander S Shashkov, Evelina L Zdorovenko, Vladimir V Ignatov, Yuriy A Knirel
An O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of bacteria Pseudomonas putida TSh-18, capable of degrading non-ionogenic technical detergents. The polysaccharide was found to contain a rarely occurring sugar derivative 4,6-dideoxy-4-[(R)-3-hydroxybutanoylamino]-d-galactose [d-Fucp4N(RHb)]. Sugar and methylation analyses, Smith degradation, solvolysis with CF3CO2H, and (1)H and (13)C NMR spectroscopy enabled elucidation of the following structure of the branched trisaccharide repeating units of the polysaccharide...
May 22, 2017: Carbohydrate Research
Youran Li, Jingjing Xu, Liang Zhang, Zhongyang Ding, Zhenghua Gu, Guiyang Shi
Debranching enzymes contribute to the enzymatic production of resistant starch (RS) by reducing substrate molecular weight and increasing amylose yield. In the present study, the action pattern of a thermostable isoamylase-type debranching enzyme on different types of starch was investigated. The molecular weight distribution, glycosidic bond composition and contents of oligosaccharides released were monitored by various liquid chromatography techniques and nuclear magnetic resonance spectroscopy (NMR). These analyses showed that the isoamylase could specifically and efficiently attack α-1,6-glucosidic linkages at branch points, leaving the amylose favored by other amylolytic enzymes...
May 22, 2017: Carbohydrate Research
Takayuki Kato, Andrea Vasella, David Crich
The stereospecifically labeled 6-monodeuterio methyl 2,6-diamino-2,6-dideoxy-α- and β- d-glucopyranosides were synthesized with a view to determining their side chain conformations. NMR studies in D2O at pH 5 and pH 11 reveal both anomers to adopt very predominantly the gt conformation consistent with the gauche conformation of 2-aminoethanol and its acetate salt. In contrast, as also revealed with the help of stereospecifically-labelled monodeuterio isotopomers, the methyl 2-amino-2-deoxy-α- and β- d-glucopyranosides are an approximately 1:1 mixture of gg and gt conformers as is found in glucopyranose itself...
May 19, 2017: Carbohydrate Research
Dominik Walczak, Andrzej Nowacki, Damian Trzybiński, Justyna Samaszko-Fiertek, Henryk Myszka, Artur Sikorski, Beata Liberek
N-(α-d-Glucofuranurono-6,3-lactone)-p-nitroaniline and N-(methyl β-d-glucopyranuronate)-p-nitroaniline were obtained as crystalline solids. The single-crystal X-ray diffraction, NMR data and DFT calculations for N-(α-d-glucofuranurono-6,3-lactone)-p-nitroaniline indicate that this N-furanoside adopts a (3)T2/(3)E-like conformation in the crystal lattice, solution and gas phase. Thus, the structure of recorded for N-furanoside (1)H NMR spectrum is indicative of the (3)T2/(3)E region of the pseudorotational itinerary for furanose derivatives with α-d-gluco, β-L-ido and α-d-xylo configurations...
May 19, 2017: Carbohydrate Research
Jean-Guy Berrin, Marie-Noëlle Rosso, Maher Abou Hachem
Enzymatic degradation of plant biomass is of growing interest for the development of a sustainable bio-based industry. Filamentous fungi, which degrade complex and recalcitrant plant polymers, are proficient secretors of enzymes acting on the lignocellulose composite of plant cell walls in addition to starch, the main carbon storage reservoir. In this review, we focus on the identification of lytic polysaccharide monooxygenases (LPMOs) and their redox partners in fungal secretomes to highlight the biological functions of these remarkable enzyme systems and we discuss future trends related to LPMO-potentiated bioconversion...
May 17, 2017: Carbohydrate Research
Toshiyuki Suzuki, Mitsuo Ishida, Toshihiro Kumazawa, Shingo Sato
In the synthesis of the main yellow pigment hydroxysafflor yellow A (HSYA), that is present in safflower petals, the key compound 4-(S)-2-acetyl-4,6-di-C-(per-O-acetyl-β-D-glucosyl)-3,4-dihydroxy-5-methoxycyclohexa-2,5-dienone (11b) was diastereoselectively synthesized in an overall yield of 18% from di-C-β-D-glucosylphloroacetophenone per-O-acetate (8).
May 13, 2017: Carbohydrate Research
Paul N Handley, Anthony Carroll, Vito Ferro
The oligosaccharide phosphate fraction (OPF) obtained from mild acid hydrolysis of P. holstii NRRL Y-2448 phosphomannan is the starting material for the preparation of the Phase III anticancer drug candidate PI-88. The OPF was for the first time successfully separated by preparative ion exchange chromatography and the major oligosaccharides isolated and characterized by NMR spectroscopy. The components were also acetylated and subjected to LC-MS analysis. These studies revealed that the OPF also contained all-α(1 → 3)-linked oligosaccharides in addition to the known α(1 → 3)/(1 → 2)-linked species, most likely formed by hydrolysis of the latter...
May 13, 2017: Carbohydrate Research
Nan Li, Jian Miao, Jing Li, Yu-Ru Zhao, Hong-Mei Li, Yi-Qun Dai, Qiang Huo, Cheng-Zhu Wu, Tao Ma
Corylifol A, a member of the isoflavone subclass of isoflavonoids, has long been considered to have various biological activities. Here, we sought to synthesize corylifol A glucosides by the in vitro glucosylation reaction using the UDP-glycosyltransferase YjiC from Bacillus licheniformis DSM 13, and obtained two novel glucosides: corylifol A-4',7-di-O-beta-d-glucopyranoside (1) and corylifol A-4'-O-beta-d-glucopyranoside (2). To improve the yield of the products, the reaction time, concentration of UDP-glucose, and pH of the buffer were optimized...
May 11, 2017: Carbohydrate Research
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