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  Subjects -> CHEMISTRY (Total: 845 journals)
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    - CHEMISTRY (596 journals)
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CHEMISTRY (596 journals)                  1 2 3 | Last

Showing 1 - 200 of 735 Journals sorted alphabetically
2D Materials     Hybrid Journal   (Followers: 6)
Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement     Hybrid Journal   (Followers: 26)
ACS Catalysis     Full-text available via subscription   (Followers: 31)
ACS Chemical Neuroscience     Full-text available via subscription   (Followers: 17)
ACS Combinatorial Science     Full-text available via subscription   (Followers: 23)
ACS Macro Letters     Full-text available via subscription   (Followers: 22)
ACS Medicinal Chemistry Letters     Full-text available via subscription   (Followers: 37)
ACS Nano     Full-text available via subscription   (Followers: 216)
ACS Photonics     Full-text available via subscription   (Followers: 10)
ACS Synthetic Biology     Full-text available via subscription   (Followers: 20)
Acta Chemica Iasi     Open Access   (Followers: 2)
Acta Chimica Sinica     Full-text available via subscription  
Acta Chimica Slovaca     Open Access   (Followers: 1)
Acta Chromatographica     Full-text available via subscription   (Followers: 8)
Acta Facultatis Medicae Naissensis     Open Access  
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 5)
Acta Scientifica Naturalis     Open Access   (Followers: 2)
adhäsion KLEBEN & DICHTEN     Hybrid Journal   (Followers: 5)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 7)
Adsorption Science & Technology     Full-text available via subscription   (Followers: 5)
Advanced Functional Materials     Hybrid Journal   (Followers: 47)
Advanced Science Focus     Free   (Followers: 3)
Advances in Chemical Engineering and Science     Open Access   (Followers: 53)
Advances in Chemical Science     Open Access   (Followers: 12)
Advances in Chemistry     Open Access   (Followers: 12)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 18)
Advances in Drug Research     Full-text available via subscription   (Followers: 22)
Advances in Enzyme Research     Open Access   (Followers: 10)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 8)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 14)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 8)
Advances in Materials Physics and Chemistry     Open Access   (Followers: 18)
Advances in Nanoparticles     Open Access   (Followers: 12)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 15)
Advances in Polymer Science     Hybrid Journal   (Followers: 40)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 18)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 17)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 5)
Advances in Science and Technology     Full-text available via subscription   (Followers: 10)
African Journal of Bacteriology Research     Open Access  
African Journal of Chemical Education     Open Access   (Followers: 2)
African Journal of Pure and Applied Chemistry     Open Access   (Followers: 7)
Agrokémia és Talajtan     Full-text available via subscription   (Followers: 2)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 3)
AMB Express     Open Access   (Followers: 1)
Ambix     Hybrid Journal   (Followers: 3)
American Journal of Biochemistry and Biotechnology     Open Access   (Followers: 65)
American Journal of Biochemistry and Molecular Biology     Open Access   (Followers: 14)
American Journal of Chemistry     Open Access   (Followers: 25)
American Journal of Plant Physiology     Open Access   (Followers: 12)
American Mineralogist     Full-text available via subscription   (Followers: 12)
Analyst     Full-text available via subscription   (Followers: 39)
Angewandte Chemie     Hybrid Journal   (Followers: 148)
Angewandte Chemie International Edition     Hybrid Journal   (Followers: 204)
Annales UMCS, Chemia     Open Access   (Followers: 1)
Annals of Clinical Chemistry and Laboratory Medicine     Open Access   (Followers: 1)
Annual Reports in Computational Chemistry     Full-text available via subscription   (Followers: 3)
Annual Reports Section A (Inorganic Chemistry)     Full-text available via subscription   (Followers: 3)
Annual Reports Section B (Organic Chemistry)     Full-text available via subscription   (Followers: 7)
Annual Review of Chemical and Biomolecular Engineering     Full-text available via subscription   (Followers: 12)
Annual Review of Food Science and Technology     Full-text available via subscription   (Followers: 14)
Anti-Infective Agents     Hybrid Journal   (Followers: 3)
Antiviral Chemistry and Chemotherapy     Hybrid Journal  
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 6)
Applied Spectroscopy     Full-text available via subscription   (Followers: 22)
Applied Surface Science     Hybrid Journal   (Followers: 24)
Arabian Journal of Chemistry     Open Access   (Followers: 6)
ARKIVOC     Open Access   (Followers: 2)
Asian Journal of Biochemistry     Open Access   (Followers: 1)
Atomization and Sprays     Full-text available via subscription   (Followers: 3)
Australian Journal of Chemistry     Hybrid Journal   (Followers: 7)
Autophagy     Hybrid Journal   (Followers: 2)
Avances en Quimica     Open Access   (Followers: 1)
Biochemical Pharmacology     Hybrid Journal   (Followers: 9)
Biochemistry     Full-text available via subscription   (Followers: 266)
Biochemistry Insights     Open Access   (Followers: 5)
Biochemistry Research International     Open Access   (Followers: 6)
BioChip Journal     Hybrid Journal  
Bioinorganic Chemistry and Applications     Open Access   (Followers: 9)
Bioinspired Materials     Open Access   (Followers: 3)
Biointerface Research in Applied Chemistry     Open Access   (Followers: 2)
Biointerphases     Open Access   (Followers: 1)
Biology, Medicine, & Natural Product Chemistry     Open Access  
Biomacromolecules     Full-text available via subscription   (Followers: 18)
Biomass Conversion and Biorefinery     Partially Free   (Followers: 10)
Biomedical Chromatography     Hybrid Journal   (Followers: 6)
Biomolecular NMR Assignments     Hybrid Journal   (Followers: 3)
BioNanoScience     Partially Free   (Followers: 4)
Bioorganic & Medicinal Chemistry     Hybrid Journal   (Followers: 105)
Bioorganic & Medicinal Chemistry Letters     Hybrid Journal   (Followers: 98)
Bioorganic Chemistry     Hybrid Journal   (Followers: 10)
Biopolymers     Hybrid Journal   (Followers: 17)
Biosensors     Open Access   (Followers: 1)
Biotechnic and Histochemistry     Hybrid Journal   (Followers: 1)
Bitácora Digital     Open Access  
Boletin de la Sociedad Chilena de Quimica     Open Access  
Bulletin of the Chemical Society of Ethiopia     Open Access   (Followers: 3)
Bulletin of the Chemical Society of Japan     Full-text available via subscription   (Followers: 24)
Bulletin of the Korean Chemical Society     Hybrid Journal   (Followers: 1)
C - Journal of Carbon Research     Open Access   (Followers: 2)
Canadian Association of Radiologists Journal     Full-text available via subscription   (Followers: 2)
Canadian Journal of Chemistry     Full-text available via subscription   (Followers: 10)
Canadian Mineralogist     Full-text available via subscription   (Followers: 3)
Carbohydrate Research     Hybrid Journal   (Followers: 26)
Carbon     Hybrid Journal   (Followers: 66)
Catalysis for Sustainable Energy     Open Access   (Followers: 6)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 8)
Catalysis Science and Technology     Free   (Followers: 6)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 3)
Catalysts     Open Access   (Followers: 7)
Cellulose     Hybrid Journal   (Followers: 7)
Cereal Chemistry     Full-text available via subscription   (Followers: 4)
ChemBioEng Reviews     Full-text available via subscription   (Followers: 1)
ChemCatChem     Hybrid Journal   (Followers: 8)
Chemical and Engineering News     Free   (Followers: 11)
Chemical Bulletin of Kazakh National University     Open Access  
Chemical Communications     Full-text available via subscription   (Followers: 68)
Chemical Engineering Research and Design     Hybrid Journal   (Followers: 22)
Chemical Research in Chinese Universities     Hybrid Journal   (Followers: 3)
Chemical Research in Toxicology     Full-text available via subscription   (Followers: 19)
Chemical Reviews     Full-text available via subscription   (Followers: 167)
Chemical Science     Open Access   (Followers: 21)
Chemical Technology     Open Access   (Followers: 15)
Chemical Vapor Deposition     Hybrid Journal   (Followers: 4)
Chemical Week     Full-text available via subscription   (Followers: 7)
Chemie in Unserer Zeit     Hybrid Journal   (Followers: 55)
Chemie-Ingenieur-Technik (Cit)     Hybrid Journal   (Followers: 25)
ChemInform     Hybrid Journal   (Followers: 7)
Chemistry & Biodiversity     Hybrid Journal   (Followers: 6)
Chemistry & Biology     Full-text available via subscription   (Followers: 30)
Chemistry & Industry     Hybrid Journal   (Followers: 5)
Chemistry - A European Journal     Hybrid Journal   (Followers: 131)
Chemistry - An Asian Journal     Hybrid Journal   (Followers: 15)
Chemistry and Materials Research     Open Access   (Followers: 17)
Chemistry Central Journal     Open Access   (Followers: 4)
Chemistry Education Research and Practice     Free   (Followers: 5)
Chemistry in Education     Open Access   (Followers: 8)
Chemistry International     Hybrid Journal   (Followers: 2)
Chemistry Letters     Full-text available via subscription   (Followers: 43)
Chemistry of Materials     Full-text available via subscription   (Followers: 183)
Chemistry of Natural Compounds     Hybrid Journal   (Followers: 9)
Chemistry-Didactics-Ecology-Metrology     Open Access  
ChemistryOpen     Open Access   (Followers: 2)
Chemkon - Chemie Konkret, Forum Fuer Unterricht Und Didaktik     Hybrid Journal  
Chemoecology     Hybrid Journal   (Followers: 2)
Chemometrics and Intelligent Laboratory Systems     Hybrid Journal   (Followers: 15)
Chemosensors     Open Access  
ChemPhysChem     Hybrid Journal   (Followers: 8)
ChemPlusChem     Hybrid Journal   (Followers: 2)
ChemTexts     Hybrid Journal  
CHIMIA International Journal for Chemistry     Full-text available via subscription   (Followers: 3)
Chinese Journal of Chemistry     Hybrid Journal   (Followers: 6)
Chinese Journal of Polymer Science     Hybrid Journal   (Followers: 10)
Chromatographia     Hybrid Journal   (Followers: 22)
Chromatography Research International     Open Access   (Followers: 7)
Clay Minerals     Full-text available via subscription   (Followers: 9)
Cogent Chemistry     Open Access  
Colloid and Interface Science Communications     Open Access  
Colloid and Polymer Science     Hybrid Journal   (Followers: 10)
Colloids and Surfaces B: Biointerfaces     Hybrid Journal   (Followers: 8)
Combinatorial Chemistry & High Throughput Screening     Hybrid Journal   (Followers: 3)
Combustion Science and Technology     Hybrid Journal   (Followers: 18)
Comments on Inorganic Chemistry: A Journal of Critical Discussion of the Current Literature     Hybrid Journal   (Followers: 2)
Composite Interfaces     Hybrid Journal   (Followers: 5)
Comprehensive Chemical Kinetics     Full-text available via subscription   (Followers: 2)
Comptes Rendus Chimie     Full-text available via subscription  
Comptes Rendus Physique     Full-text available via subscription   (Followers: 1)
Computational and Theoretical Chemistry     Hybrid Journal   (Followers: 9)
Computational Biology and Chemistry     Hybrid Journal   (Followers: 12)
Computational Chemistry     Open Access   (Followers: 2)
Computers & Chemical Engineering     Hybrid Journal   (Followers: 9)
Coordination Chemistry Reviews     Full-text available via subscription   (Followers: 2)
Copernican Letters     Open Access  
Critical Reviews in Biochemistry and Molecular Biology     Hybrid Journal   (Followers: 5)
Crystal Structure Theory and Applications     Open Access   (Followers: 3)
CrystEngComm     Full-text available via subscription   (Followers: 10)
Current Catalysis     Hybrid Journal   (Followers: 2)
Current Metabolomics     Hybrid Journal   (Followers: 3)
Current Opinion in Colloid & Interface Science     Hybrid Journal   (Followers: 9)
Current Research in Chemistry     Open Access   (Followers: 8)
Current Science     Open Access   (Followers: 48)
Dalton Transactions     Full-text available via subscription   (Followers: 18)
Detection     Open Access   (Followers: 2)
Developments in Geochemistry     Full-text available via subscription   (Followers: 2)
Diamond and Related Materials     Hybrid Journal   (Followers: 11)
Dislocations in Solids     Full-text available via subscription  
Doklady Chemistry     Hybrid Journal  
Drying Technology: An International Journal     Hybrid Journal   (Followers: 3)
Eclética Química     Open Access   (Followers: 1)
Ecological Chemistry and Engineering S     Open Access   (Followers: 4)
Ecotoxicology and Environmental Contamination     Open Access  
Educación Química     Open Access   (Followers: 1)
Education for Chemical Engineers     Hybrid Journal   (Followers: 5)
Elements     Full-text available via subscription   (Followers: 2)
Environmental Chemistry     Hybrid Journal   (Followers: 7)
Environmental Chemistry Letters     Hybrid Journal   (Followers: 4)
Environmental Science & Technology Letters     Full-text available via subscription   (Followers: 5)
Environmental Science : Nano     Partially Free   (Followers: 1)
Environmental Toxicology & Chemistry     Hybrid Journal   (Followers: 19)
Enzyme Research     Open Access   (Followers: 4)

        1 2 3 | Last

Journal Cover Carbohydrate Research
  [SJR: 0.612]   [H-I: 98]   [26 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0008-6215 - ISSN (Online) 0008-6215
   Published by Elsevier Homepage  [3051 journals]
  • Synthesis and revised stereochemical assignment of C-allyl
           glucopyranosides and derivatives
    • Abstract: Publication date: 5 June 2017
      Source:Carbohydrate Research, Volume 445
      Author(s): Nicolas Petry, Timothé Vucko, Charlotte Collet, Sandrine Lamandé-Langle, Nadia Pellegrini-Moïse, Françoise Chrétien
      α- and β-C-allylglucopyranosides and hydroxy-, bromo- and azido-derivatives were prepared through allylation at C-1 of methyl 2,3,4,6-tetra-O-benzyl-D-glucopyranoside or 1-O-acetyl-2,3,4,6-tetra-O-benzyl-D-glucopyranose and subsequent chemical modifications of the alkene on the anomeric arm. However, we picked out some discordance between some recent published studies and our results. After a thorough work of characterization and NMR analysis, we unambiguously confirmed α and β stereochemistry of the two series of compounds and fully described for the first time β-C-propyl alcohol, bromide and azide of 2,3,4,6-tetra-O-benzyl-D-glucopyranose.
      Graphical abstract image

      PubDate: 2017-04-17T07:28:24Z
       
  • Flavanonol glucosides from the aerial parts of Agrimonia pilosa Ledeb. and
           their acetylcholinesterase inhibitory effects
    • Abstract: Publication date: Available online 15 April 2017
      Source:Carbohydrate Research
      Author(s): U. Min Seo, Duc Hung Nguyen, Bing Tian Zhao, Byung Sun Min, Mi Hee Woo
      Two new flavanonol glucoside isomers, (2R,3S)-dihydrokaempferol 3-O-β-D-glucoside (1) and (2S,3R)-dihydrokaempferol 3-O-β-D-glucoside (2), were isolated from the aerial parts of Agrimonia pilosa Ledeb., along with eight known flavanonol glucosides (3–10). Their structures were determined on the basis of spectroscopic analysis. In addition, these compounds were evaluated to determine their acetylcholinesterase inhibitory activities. The results indicated that these compounds have moderate inhibitory effects, with IC50 values ranging from 76.59 ± 1.16 to 97.53 ± 1.64 μM, except compounds 1 and 4 were inactive.
      Graphical abstract image

      PubDate: 2017-04-17T07:28:24Z
       
  • Structure and gene cluster of a tyvelose-containing O-polysaccharide of an
           entomopathogenic bacterium Yersinia entomophaga MH96T related to Yersinia
           pseudotuberculosis
    • Abstract: Publication date: Available online 15 April 2017
      Source:Carbohydrate Research
      Author(s): O.V. Sizova, A.N. Kondakova, A.S. Shashkov, Y.A. Knirel, R.Z. Shaikhutdinova, S.A. Ivanov, M.E. Platonov, M.R.H. Hurst, S.V. Dentovskaya
      An O-polysaccharide was isolated from the lipopolysaccharide of an entomopathogenic bacterium Yersinia entomophaga MH96T by mild acid hydrolysis and studied by 2D NMR spectroscopy. The following structure of the branched tetrasaccharide repeating unit of the polysaccharide was established: Image 2 where Tyv indicates 3,6-dideoxy-d-arabino-hexose (tyvelose). The structure established is consistent with the gene content of the O-antigen gene cluster. The O-polysaccharide structure and gene cluster of Y. entomophaga are related to those of some Y. pseudotuberculosis serotypes.
      Graphical abstract image

      PubDate: 2017-04-17T07:28:24Z
       
  • Reactivity studies in water on the acid-catalysed dehydration of psicose
           compared to other ketohexoses into 5-hydroxymethylfurfural
    • Abstract: Publication date: Available online 13 April 2017
      Source:Carbohydrate Research
      Author(s): Robert-Jan van Putten, Jan C. van der Waal, Ed de Jong, Hero J. Heeres
      The conversion of the four possible ketohexoses (fructose, tagatose, sorbose and psicose) into 5-hydroxymethylfurfural (HMF) was explored in water using sulphuric acid as the catalyst (33 mM H2SO4, 120 °C). Significant differences in reactivity were observed and tagatose (48% conversion after 75 min) and psicose (35% conversion after 75 min) were clearly more reactive than fructose and sorbose (around 20% conversion after 75 min). The selectivity to HMF was found to be higher for fructose and psicose than for tagatose and sorbose. 2-Hydroxyacetylfuran (HAF) was shown to be a by-product for mainly sorbose and tagatose (as high as 2% yield). The results indicate that the relative orientation of the hydroxyl groups on C3 and C4 has a major effect on the reactivity and selectivity. This suggests that the dehydration towards HMF takes place via a mechanism with cyclic intermediates in which the C3-C4 bond is fixed in a ring structure. A reaction mechanism involving a bicyclic structure is proposed to explain the formation of HAF. The reactivity of the sugars was significantly lower in water than previously observed in methanol.
      Graphical abstract image

      PubDate: 2017-04-17T07:28:24Z
       
  • Improved quantification of monosaccharides in complex lignocellulosic
           biomass matrices: A gas chromatography-mass spectrometry based approach
    • Abstract: Publication date: Available online 13 April 2017
      Source:Carbohydrate Research
      Author(s): Thomas Zweckmair, Sonja Schiehser, Thomas Rosenau, Antje Potthast
      A novel method for the precise and accurate quantification of wood monosaccharides by gas-chromatography mass-spectrometry in complex lignocellulosic biomass matrices is presented. Instead of using the syn- or the anti peak obtained by blocking the anomeric center using e.g. oximation, the sum of each syn- and anti-peak pair is used for quantification rendering the approach independent from an apparently constant syn- and anti-peak area ratio. Each wood monosaccharide syn- and anti-peak could essentially be distinguished upon O-ethoximation followed by trifluoroacetylation and separation on a 14% cyanopropyl/phenyl- 86% dimethylpoly-siloxane column. Additionally, internal standardization is carried out applying isotopically labeled compounds. Hence, the analytical figures of merit such as precision and accuracy in biorefinery sample matrices could be substantially improved compared to standard gas-chromatography mass spectrometry as well as high-performance anion exchange chromatography (HPAEC) coupled to pulsed-amperometric detection (PAD) techniques. The applicability of the novel gas-chromatography mass-spectrometry approach is demonstrated analyzing five selected lignocellulosic biomass sample matrices typically occurring in a biorefinery scenario. Even in heavily loaded sample matrices precise and accurate data is obtained when using the novel methodology presented.
      Graphical abstract image

      PubDate: 2017-04-17T07:28:24Z
       
  • A bioinformatics analysis of 3400 lytic polysaccharide oxidases from
           family AA9
    • Abstract: Publication date: Available online 13 April 2017
      Source:Carbohydrate Research
      Author(s): Nicolas Lenfant, Matthieu Hainaut, Nicolas Terrapon, Elodie Drula, Vincent Lombard, Bernard Henrissat
      Lytic polysaccharide monooxygenases of family AA9 catalyze the oxidative cleavage of glycosidic bonds in cellulose and related polysaccharides. The N-terminal half of AA9 LPMOs displays a huge sequence variability that is in contradiction with the substrate simplicity so far observed for these enzymes. To understand the cause of the high multigenicity that prevails in the family, we have performed a clustering analysis of the N-terminal region of 3400 sequences of family AA9 LPMOs, and have evaluated the coincidence of the clusters with distal visible features that may accompany functional differences. A method based on local pairwise alignments was devised to avoid the pitfalls of a global multiple alignment. Our analysis allowed the definition of 64 clusters, which successfully segregated several visible features associated to LPMO family AA9, such as the presence of carbohydrate-binding modules, of modules of unknown function and of the conspicuous H > R substitution at the first residue of the histidine brace that holds the catalytic copper. Our analysis shows that the hypervariability of the N-terminal half of the AA9 sequences is not driven by random evolution as sequence similarity does not follow solely taxonomy. The results suggest that some clusters are perhaps able to target chitin instead of cellulose, and that preference for C1 or C4 oxidation (or lack thereof), does not appear to constitute a strong evolutionary constraint. On an evolutionary standpoint, there seems to be little constraints that apply to the N-terminal half of the sequences other than the conservation of the histidine brace. The weak evolutionary constraints that apply to the N-terminal half of AA9 LPMOs explain both their hypervariability and multigenicity.
      Graphical abstract image

      PubDate: 2017-04-17T07:28:24Z
       
  • A glucose-sensitive block glycopolymer hydrogel based on dynamic boronic
           ester bonds for insulin delivery
    • Abstract: Publication date: 5 June 2017
      Source:Carbohydrate Research, Volume 445
      Author(s): Baoqi Cai, Yanping Luo, Qianqian Guo, Xinge Zhang, Zhongming Wu
      Hydrogels are good candidates to satisfy many needs for functional and tunable biomaterials. How to precisely control the gel structure and functions is crucial for the construction of sophisticated soft biomaterials comprising the hydrogels, which facilitates the impact of the surrounding environment on a unique biological function occurring. Here, glucose-responsive hydrogels comprised of 3-acrylamidophenyl boronic acid copolymerized with 2-lactobionamidoethyl methacrylate (p(APBA-b-LAMA)) were synthesized, and further evaluated as carriers for insulin delivery. The formation of (p(APBA-b-LAMA)) hydrogel was based on dynamic covalent bond using the association of boronic acid with diols. P(APBA-b-LAMA) hydrogel with the typical porous structure showed a rapid increase in equilibrium of swelling, which was up to 1856% after incubation with aqueous solution. Using insulin as a model protein therapeutic, p(APBA-b-LAMA) hydrogel exhibited high drug loading capability up to 15.6%, and also displayed glucose-dependent insulin release under physiological conditions. Additionally, the viability of NIH3T3 cells was more than 90% after treated with p(APBA-b-LAMA) hydrogel, indicating that the hydrogel had no cytotoxicity. Consequently, the novel p(APBA-b-LAMA) hydrogel has a practical application for diabetes treatment.
      Graphical abstract image

      PubDate: 2017-04-10T18:16:14Z
       
  • Characterization of O-antigen polysaccharide backbone derived from nitric
           oxide-inducing Mesorhizobium loti MAFF 303099 lipopolysaccharide
    • Abstract: Publication date: 5 June 2017
      Source:Carbohydrate Research, Volume 445
      Author(s): Masahito Hashimoto, Masato Mizukami, Ken-ichi Osuki, Nagatoshi Fujiwara, Yasuo Suda, Toshiki Uchiumi
      Mesorhizobium loti is a member of rhizobia and establishes nitrogen-fixing symbioses with several Lotus species. Recently, we reported that M. loti MAFF 303099 bacterial cells and their lipopolysaccharide (LPS) preparations are involved in the beginning of the symbiotic process by inducing transient nitric oxide (NO) production in the roots of L. japonicus. We subsequently found that both the polysaccharide (PS) part and the lipid A moiety in LPS are responsible for the NO induction. In this study, we elucidated the chemical structure of M. loti O-polysaccharide (OPS) in PS. PS was prepared by mild acid hydrolysis of M. loti LPS followed by gel filtration chromatography. OPS was subjected to hydrazine treatment to obtain deacylated PS (dPS). Chemical composition analysis, ethylation analysis, and NMR spectra revealed the chemical structure of the M. loti OPS backbone in dPS to be →2)-α-l-6dTalp-(1 → 3)-α-l-6dTalp-(1 → 2)-α-l-Rhap-(1 → 2)-α-l-6dTalp-(1 → 3)-α-l-6dTalp-(1 → 3)-α-l-Rhap-(1→.
      Graphical abstract image

      PubDate: 2017-04-10T18:16:14Z
       
  • Determination of mole fractions of ethyl-cellulose-containing monomers by
           NMR
    • Abstract: Publication date: 5 June 2017
      Source:Carbohydrate Research, Volume 445
      Author(s): Hiroyuki Kono
      Three samples of ethyl cellulose (EC) with different degrees of substitution (DS)—0.51, 1.41, and 2.28—were prepared by a slurry method using ethyl bromide as the etherification reagent. 1H–13C HSQC and HSQC-TOCSY NMR spectral analysis allowed for complete assignment of the 1H and 13C chemical shifts, respectively, of eight anhydroglucose units (AGUs) comprising EC chains—un-, 2-mono-, 3-mono-, 6-mono-, 2,3-di-, 2,6-di-, 3,6-di-, and 2,3,6-tri-substituted AGUs. In addition, the lineshape of the quantitative 13C NMR spectra of the three EC samples provided change in the mole fractions of these AGUs against DS, making it possible to estimate the reaction mechanism for the production of EC, elucidating reactivities of the hydroxyl groups at the 2, 3, and 6 positions of cellulose and interactions between the substituent groups within the same AGU and vicinal AGUs.
      Graphical abstract image

      PubDate: 2017-04-10T18:16:14Z
       
  • Identification and biochemical characterization of a novel
           α-1,3-mannosyltransferase WfcD from Escherichia coli O141
    • Abstract: Publication date: 18 April–12 May 2017
      Source:Carbohydrate Research, Volumes 443–444
      Author(s): Chao Chen, Xi Hou, Natalia Utkina, Leonid Danilov, Dawei Zhou, Vladimir Torgov, Vladimir Veselovsky, Bin Liu, Lu Feng
      Glycosyltransferases (GTs) catalyze the formation of regio- and stereospecific glycosidic linkages between specific sugar donors and recipients. In this study, the function of the wfcD gene from the Escherichia coli O141 O-antigen gene cluster encoding an α-1,3-mannosyltransferase that catalyzed the formation of the linkage Man(α1-3)-GlcNAc was biochemically characterized. WfcD was expressed in E. coli BL21 (DE3), and the enzymatic product was identified by liquid chromatography-mass spectrometry (LC-MS), collision-induced dissociation electrospray ionization ion trap multiple tandem MS (CID-ESI-IT-MSn) and glycosidase digestion using the donor substrate GDP-Man and the synthetic acceptor substrate decyl diphosphate 2-acetamido-2-deoxy-α-D-glucopyranose (GlcNAc-PP-De). The kinetic and physiochemical properties and the substrate specificity of WfcD were investigated. WfcD is the first characterized bacterial mannosyltransferase that acts on the Man(α1-3)-GlcNAc linkage. This study enhances our knowledge of the diverse functions of GTs.
      Graphical abstract image

      PubDate: 2017-04-10T18:16:14Z
       
  • Recombinant expression of Thermobifida fusca E7 LPMO in Pichia pastoris
           and Escherichia coli and their functional characterization
    • Abstract: Publication date: Available online 9 April 2017
      Source:Carbohydrate Research
      Author(s): Kelly B. Rodrigues, Jéssica K.A. Macêdo, Tallyta Teixeira, Jéssica S. Barros, Ana C.B. Araújo, Fernanda P. Santos, Betânia F. Quirino, Bruno S.A.F. Brasil, Thaís F.C. Salum, Patrícia V. Abdelnur, Léia C.L. Fávaro
      The discovery of lytic polysaccharides monooxygenases copper dependent (LPMOs) revolutionized the classical concept that the cleavage of cellulose is a hydrolytic process in recent years. These enzymes carry out oxidative cleavage of cellulose (and other polysaccharides), acting synergistically with cellulases and other hydrolases. In fact, LPMOs have the potential for increasing the efficiency of the lignocellulosic biomass conversion in biofuels and high value chemicals. Among a small number of microbial LPMOs that have been characterized, some LPMOs were expressed and characterized biochemically from the bacteria Thermobifida fusca, using the host Escherichia coli. In this work, the E7 LPMO protein of T. fusca was expressed both in E. coli (native DNA sequence) and Pichia pastoris (codon-optimized DNA sequence), for further analysis of oxidative cleavage, with PASC (phosphoric acid swollen cellulose) and Avicel PH-101 substrates, using mass spectrometry analysis. Mass spectra results of Avicel PH-101 and PASC cleavages by purified E7 LPMO expressed in E. coli and in P. pastoris allowed the visualization of compounds corresponding to oxidized and non-oxidized oligosaccharides. Further optimization of reactions will be performed, since it was found only one degree of polymerization (DP 7). This work demonstrated that it is possible to produce the E7 LPMO from T. fusca in the host P. pastoris, and the recombinant protein was shown to be active on cellulose. The approach used in the present work could be an alternative to produce this bacterial LPMO for cellulose cleavage.
      Graphical abstract image

      PubDate: 2017-04-10T18:16:14Z
       
  • Studies on the 6-homologation of β-D-idopyranosides
    • Abstract: Publication date: Available online 8 April 2017
      Source:Carbohydrate Research
      Author(s): Rachel Hevey, Chang-Chun Ling
      β-D-Idopyranosides are interesting sugars because of their unusual conformational flexibility in the pyranosyl ring, and also their β-1,2-cis-anomeric configuration. Here we report on studies of the regioselective opening of 4,6-O-benzylidene-protected β-D-idopyranosides under reducing conditions, and the subsequent 6-homologation via Swern oxidation and Wittig olefination to afford a 6,7-dideoxy-β-D-ido-hept-6-enopyranoside. This olefination product was found to adopt predominantly 1C4 conformation in solution by NMR experiments, which places the vinyl group at a more sterically hindered axial position and creates difficulty in subsequent hydroborations.
      Graphical abstract image

      PubDate: 2017-04-10T18:16:14Z
       
  • Enzymatic synthesis and semi-preparative isolation of N-acetylmuramic acid
           6-phosphate
    • Abstract: Publication date: Available online 6 April 2017
      Source:Carbohydrate Research
      Author(s): Sandra Unsleber, Marina Borisova, Christoph Mayer
      N-acetylmuramic acid 6-phosphate (MurNAc-6P) is a constituent of the bacterial peptidoglycan cell wall, serving as an anchor point of secondary cell wall polymers such as teichoic acids, and it is a key metabolite of the peptidoglycan recycling metabolism. Thus, there is a demand for MurNAc-6P as a standard for cell wall compositional and metabolic analyses and, in addition, as a substrate for peptidoglycan recycling enzymes, e.g. MurNAc-6P etherases (MurQ) and MurNAc-6P phosphatases (MupP), or as an effector molecule of transcriptional MurR regulators. However, MurNAc-6P is commercially not available. We report here the facile enzymatic production of MurNAc-6P in mg-scale from MurNAc and ATP, applying Clostridium acetobutylicum kinase MurK, and purification by semi-preparative HPLC. MurNAc-6P was quantified using a coupled enzyme assay, revealing 75–80% overall product yield, and high purity was confirmed by mass spectrometry and proton NMR.
      Graphical abstract image

      PubDate: 2017-04-10T18:16:14Z
       
  • Cycloartane triterpenoid saponins from the herbs of Thalictrum fortunei
    • Abstract: Publication date: 5 June 2017
      Source:Carbohydrate Research, Volume 445
      Author(s): Si-Qi Jiang, Yu-Bo Zhang, Min Xiao, Lin Jiang, Ding Luo, Qian-Wen Niu, Yao-Lan Li, Xian-Tao Zhang, Guo-Cai Wang
      Six new cycloartane triterpenoid saponins, thalisides A-F (1–6), along with four known ones (7–10), were isolated from Thalictrum fortunei. The new structures were elucidated by using spectroscopic data (NMR, IR, UV, and MS). Compounds 1–10 were examined for their in vitro cytotoxicity against two human cancer cell lines (HepG2, A549) and antiviral activity against influenza A virus (H1N1) and found to be inactive.
      Graphical abstract image

      PubDate: 2017-04-02T16:54:14Z
       
  • The uniform structure of O-polysaccharides isolated from Dickeya solani
           strains of different origin
    • Abstract: Publication date: Available online 1 April 2017
      Source:Carbohydrate Research
      Author(s): Karolina Ossowska, Małgorzata Czerwicka, Wojciech Sledz, Sabina Zoledowska, Agata Motyka, Małgorzata Golanowska, Guy Condemine, Ewa Lojkowska, Zbigniew Kaczyński
      O-polysaccharides were isolated from lipopolysaccharides obtained from four different strains of plant pathogenic bacteria belonging to the species Dickeya solani: two of them were isolated in Poland (IFB0099 and IFB0158), the third in Germany (IFB0223) and the last one, D. solani Type Strain IPO2222, originated from the Netherlands. In addition, the O-polysaccharide of a closely related species D. dadantii strain 3937 was isolated. The purified polysaccharides of the five strains were analyzed using NMR spectroscopy and chemical methods. Sugar and methylation analyses, including absolute configuration assignment, together with NMR data revealed that all O-polysaccharides tested are homopolymers of 6-deoxy-d-altrose (d-6dAlt) the following structure: →2)-β-d-6dAltp-(1→
      Graphical abstract image

      PubDate: 2017-04-02T16:54:14Z
       
  • A mild acetolysis procedure for the regioselective removal of
           isopropylidene in di-O-isopropylidene-protected pyranoside systems
    • Abstract: Publication date: Available online 30 March 2017
      Source:Carbohydrate Research
      Author(s): Pengfei Zhang, Chang-Chun Ling
      A mild acetolysis method for the regioselective removal of isopropylidene group from di-O-isopropylidene-protected hexopyranosides is reported. O-Isopropylidene-protected intermediates play an important role in carbohydrate chemistry, as they are often found in commercially available furanosyl and pyranosyl materials, and some of them contain more than one O-isopropylidene groups. Methods that permit regioselective removal of O-isopropylidene groups are extremely valuable, as the number of steps in the total synthesis of complex oligosaccharides could be significantly decreased. Here we report that trifluoroacetic acid (TFA)/acetic anhydride (Ac2O) can be used to regioselectively convert one of the two O-isopropylidene groups to vicinal di-O-acetates in the di-O-isopropylidene-protected galacto- and fructo-pyranosyl systems, and the reagent is compatible with some common functionalities such as sulfonate esters, bromide, azide etc.
      Graphical abstract image

      PubDate: 2017-04-02T16:54:14Z
       
  • Assembly and inhibitory activity of monovalent mannosides terminated with
           aromatic methyl esters: The effect of naphthyl groups
    • Abstract: Publication date: Available online 29 March 2017
      Source:Carbohydrate Research
      Author(s): Hussein Al-Mughaid, Raed M. Al-Zoubi, Maha Khazaaleh, T. Bruce Grindley
      A series of monovalent α-D-mannoside ligands terminated with aromatic methyl esters have been synthesized in excellent yields using the Cu(I) catalyzed azide-alkyne 1,3-dipolar cycloaddition (“click chemistry”). These mannosides were designed to have a unique aglycone moiety (tail) that combines a triazole ring attached to aromatic methyl esters via a six carbon alkyl chain. The mannose unit of these ligands was linked at the ortho, meta, and para positions of substituted methyl benzoates and 1-, 3-, and 6-substituted methyl 2-napthaoates. In hemagglutination assays, ligands (32A-38A) showed better inhibitory activities than the standard inhibitor, methyl α-D-mannopyranoside. Overall, the naphthyl-based mannoside ligand (37A) showed the best activity and therefore merits further development.
      Graphical abstract image

      PubDate: 2017-04-02T16:54:14Z
       
  • Graphical contents list
    • Abstract: Publication date: 10 April 2017
      Source:Carbohydrate Research, Volume 442


      PubDate: 2017-03-26T16:48:08Z
       
  • Unliganded and substrate bound structures of the cellooligosaccharide
           active lytic polysaccharide monooxygenase LsAA9A at low pH
    • Abstract: Publication date: Available online 24 March 2017
      Source:Carbohydrate Research
      Author(s): Kristian E.H. Frandsen, Jens-Christian N. Poulsen, Tobias Tandrup, Leila Lo Leggio
      Lytic polysaccharide monooxygenases (LPMOs) have been found to be key components in microbial (bacterial and fungal) degradation of biomass. They are copper metalloenzymes that degrade polysaccharides oxidatively and act in synergy with glycoside hydrolases. Recently crystallographic studies carried out at pH 5.5 of the LPMO from Lentinus similis belonging to the fungal LPMO family AA9 have provided the first atomic resolution view of substrate-LPMO interactions. The LsAA9A structure presented here determined at pH 3.5 shows significant disorder of the active site in the absence of substrate ligand. Furthermore some differences are also observed in regards to substrate (cellohexaose) binding, although the major interaction with the N-terminal histidine remains unchanged.
      Graphical abstract image

      PubDate: 2017-03-26T16:48:08Z
       
  • Synthesis of β-galactosylamides as ligands of the peanut lectin. Insights
           into the recognition process
    • Abstract: Publication date: Available online 23 March 2017
      Source:Carbohydrate Research
      Author(s): María Emilia Cano, Oscar Varela, María Isabel García-Moreno, José Manuel García Fernández, José Kovensky, María Laura Uhrig
      The synthesis of mono and divalent β-galactosylamides linked to a hydroxylated chain having a C2 symmetry axis derived from l-tartaric anhydride is reported. Reference compounds devoid of hydroxyl groups in the linker were also prepared from β-galactosylamine and succinic anhydride. After functionalization with an alkynyl residue, the resulting building blocks were grafted onto different azide-equipped scaffolds through the copper catalyzed azide-alkyne cycloaddition. Thus, a family of structurally related mono and divalent β-N-galactopyranosylamides was obtained and fully characterized. The binding affinities of the ligands towards the model lectin PNA were measured by the enzyme-linked lectin assay (ELLA). The IC50 values were significantly higher than that of galactose but the presence of hydroxyl groups in the aglycone chain improved lectin recognition. Docking and molecular dynamics experiments were in accordance with the hypothesis that a hydroxyl group properly disposed in the linker could mimic the Glc O3 in the recognition process. On the other hand, divalent presentation of the ligands led to lectin affinity enhancements.
      Graphical abstract image

      PubDate: 2017-03-26T16:48:08Z
       
  • Structure of the O-specific polysaccharide from a marine bacterium
           Cellulophaga algicola
    • Abstract: Publication date: Available online 22 March 2017
      Source:Carbohydrate Research
      Author(s): Svetlana V. Tomshich, Maxim S. Kokoulin, Anatoliy I. Kalinovsky, Ol'ga I. Nedashkovskaya, Nadezhda A. Komandrova
      The O-polysaccharide was isolated from the lipopolysaccharide of Cellulophaga algicola and studied by chemical analyses along with 1H and 13C NMR spectroscopy, including 2D 1H, 1H COSY, TOCSY, ROESY, 1Н, 13С HSQC, HMBC experiments. It was found that the polysaccharide is built up of branched pentasaccharide repeating units, containing D-mannose (Man), D-glucuronic acid (GlcA), N-acetyl-D-glucosamine (GlcNAc), two L-rhamnose (Rha) residues and O-acetyl groups in a non-stoichiometric amount and has the following structure: Image 2
      Graphical abstract image

      PubDate: 2017-03-26T16:48:08Z
       
  • Synthetic glyco-O-sulfatome for profiling of human natural antibodies
    • Abstract: Publication date: Available online 22 March 2017
      Source:Carbohydrate Research
      Author(s): Galina Pazynina, Marina Sablina, Tatiana Ovchinnikova, Tatiana Tyrtysh, Svetlana Tsygankova, Alexander Tuzikov, Kira Dobrochaeva, Nadezhda Shilova, Nailia Khasbiullina, Nicolai Bovin
      Our understanding of biological role of glycans O-sulfation remains at the level of beginners due to microheterogeneity, lability and other difficulties of exact structural assignment. Partially, problem of functional investigations, especially determination of glycoepitope specificity of carbohydrate-binding proteins could be solved with the help of synthetic glycans of certain structure. Here we summing up our synthetic efforts in creation of synthetic O-sulfatome, and bring together all the synthesized in our group sulfated glycans, both existing in nature, yet undiscovered but biochemically licit, and completely unnatural. All glycans have aminoalkyl spacer group allowing immobilization on a chip. We exemplify the capabilities of O-sulfoglycan microarray (containing >70 ligands) for profiling human natural antibodies; for a number of glycans O-sulfation dramatically changes interaction with human antibodies.
      Graphical abstract image

      PubDate: 2017-03-26T16:48:08Z
       
  • Convergent strategy for the synthesis of S-linked oligoxylans
    • Abstract: Publication date: Available online 21 March 2017
      Source:Carbohydrate Research
      Author(s): Beatrice Bonora, Irene Boos, Mads H. Clausen
      Arabinoxylans (AX) are a major class of hemicellulose and an important polysaccharide component of lignocellulosic biomass. To utilize the glycan polymer effectively, it is desirable to learn more about the enzymatic hydrolysis of AXs. Well-defined glycans can help to elucidate these processes. Here, we report the efficient synthesis of a mixed O- and S-linked tetraxylan. This thio-oligosaccharide has been developed as a putative inhibitor of arabinoxylan degrading enzymes used for the saccharification of biomass. Two common approaches for the synthesis of thio-oligosaccharides, either involving 1-thioglycoside donors or thioacceptors, are presented and compared regarding byproduct formation and yields. Both methods have shown to be useful for the synthesis of thiolinkages in oligoxylans assembly. However, the success of the reaction is highly dependent on the “match” between donors and acceptors.
      Graphical abstract image

      PubDate: 2017-03-26T16:48:08Z
       
  • Quantum mechanics models of the methanol dimer: O-H…O hydrogen bonds of
           β-d-glucose moieties from crystallographic data
    • Abstract: Publication date: Available online 19 March 2017
      Source:Carbohydrate Research
      Author(s): Michael Santiago Cintrón, Glenn P. Johnson, Alfred D. French
      The interaction of two methanol molecules, simplified models of carbohydrates and cellulose, was examined using a variety of quantum mechanics (QM) levels of theory. Energy plots for hydrogen bonding distance (H…O) and angle (O-H…O) were constructed. All but two experimental structures were located in stabilized areas on the vacuum phase energy plots. Each of the 399 models was analyzed with Bader's atoms-in-molecules (AIM) theory, which showed a widespread ability by the dimer models to form O-H…O hydrogen bonds that have bond paths and Bond Critical Points. Continuum solvation calculations suggest that a portion of the energy-stabilized structures could occur in the presence of water. A survey of the Cambridge Structural Database (CSD) for all donor-acceptor interactions in β-D-glucose moieties examined the similarities and differences among the hydroxyl groups and acetal oxygen atoms that participate in hydrogen bonds. Comparable behavior was observed for the O2-H, O3-H, O4-H, and O6-H hydroxyls, acting either as acceptors or donors. Ring O atoms showed distinct hydrogen bonding behavior that favored mid-length hydrogen bonds.
      Graphical abstract image

      PubDate: 2017-03-26T16:48:08Z
       
  • On the formation and role of reactive oxygen species in light-driven LPMO
           oxidation of phosphoric acid swollen cellulose
    • Abstract: Publication date: Available online 18 March 2017
      Source:Carbohydrate Research
      Author(s): K.B. Möllers, H. Mikkelsen, T.I. Simonsen, D. Cannella, K.S. Johansen, M.J. Bjerrum, C. Felby
      Light-driven activation of lytic polysaccharide monooxygenases (LPMOs) has been attributed to the transfer of high redox potential electrons from excited photopigments to the enzyme. However, due to the formation of reactive oxygen species (ROS) in such a system, not only electrons from the pigments but also ROS could be part of the enzyme mechanism. This work investigates the role of ROS in the oxidation of phosphoric acid swollen cellulose (PASC) by a light-driven LPMO system. Our results clearly show that the addition of superoxide dismutase or catalase to remove ROS did not attenuate the capacity of the light-driven LPMO system to oxidize PASC, as measured by formation of oxidized oligosaccharides. We conclude that ROS are not part of the light-driven LPMO activation; hence, transfer of high redox potential electrons from the excited photopigment to the LPMO remains the most likely mechanism under the conditions tested in this study.
      Graphical abstract image

      PubDate: 2017-03-18T16:40:12Z
       
  • Heterologous expression, purification and characterization of three novel
           esterases secreted by the lignocellulolytic fungus Penicillium
           purpurogenum when grown on sugar beet pulp
    • Abstract: Publication date: Available online 18 March 2017
      Source:Carbohydrate Research
      Author(s): Gabriela Oleas, Eduardo Callegari, Romina Sepúlveda, Jaime Eyzaguirre
      The lignocellulolytic fungus, Penicillium purpurogenum, grows on a variety of natural carbon sources, among them sugar beet pulp. Culture supernatants of P. purpurogenum grown on sugar beet pulp were partially purified and the fractions obtained analyzed for esterase activity by zymograms. The bands with activity on methyl umbelliferyl acetate were subjected to mass spectrometry to identify peptides. The peptides obtained were probed against the proteins deduced from the genome sequence of P. purpurogenum. Eight putative esterases thus identified were chosen for future work. Their cDNAs were expressed in Pichia pastoris. The supernatants of the recombinant clones were assayed for esterase activity, and five of the proteins were active against one or more substrates: methyl umbelliferyl acetate, indoxyl acetate, methyl esterified pectin and fluorescein diacetate. Three of those enzymes were purified, further characterized and subjected to a BLAST search. Based on their amino acid sequence and properties, they were identified as follows: RAE1, pectin acetyl esterase (CAZy family CE 12); FAEA, feruloyl esterase (could not be assigned to a CAZy family) and EAN, acetyl esterase (former CAZy family CE 10).
      Graphical abstract image

      PubDate: 2017-03-18T16:40:12Z
       
  • Structural elucidation of a novel transglycosylated compound α-glucosyl
           rhoifolin and of α -glucosyl rutin by NMR spectroscopy
    • Abstract: Publication date: Available online 16 March 2017
      Source:Carbohydrate Research
      Author(s): Chisa Aoki, Yoshihiro Takeuchi, Kenjirou Higashi, Yuta Okamoto, Akihito Nakanishi, Mahamadou Tandia, Jun Uzawa, Keisuke Ueda, Kunikazu Moribe
      We report the full assignment of 1H and 13C NMR signals belonging to α-glucosyl rhoifolin (Rhf-G), a novel transglycosylated compound synthesized from a flavone glycoside, rhoifolin, as well as its chemical structure. Furthermore, we report the complete NMR signal assignment for another transglycosylated compound, α-glucosyl rutin (Rutin-G), as the signals corresponding to its sugar moieties had not been identified. Electrospray ionization-mass spectrometry along with multiple NMR methods revealed that Rhf-G possesses three sugar moieties in its chemical structure. The additional glucose was bound directly via a transglycosylation to rhoifolin at position 3a of the sugar moiety. Interestingly, intramolecular hydrogen bonds in the basic Rhf-G and Rutin-G skeletons were confirmed by HMBC experiments. These findings will be helpful for comprehensive NMR studies on transglycosylated compounds in food, cosmetic, and pharmaceutical fields.
      Graphical abstract image

      PubDate: 2017-03-18T16:40:12Z
       
  • Synthesis and conformational analysis of a simplified inositol-model of
           the Streptococcus pneumoniae 19F capsular polysaccharide repeating unit
    • Abstract: Publication date: Available online 14 March 2017
      Source:Carbohydrate Research
      Author(s): Giorgio Catelani, Felicia D'Andrea, Lorenzo Guazzelli, Alessio Griselli, Nicola Testi, Maria Assunta Chiacchio, Laura Legnani, Lucio Toma
      Carbohydrate mimics have been studied for a long time as useful sugar substitutes, both in the investigation of biological events and in the treatment of sugar-related diseases. Here we report further evaluation of the capabilities of inositols as carbohydrate substitutes. The conformational features of an inositol-model of a simplified repeating unit corresponding to the capsular polysaccharide of Streptococcus pneumoniae 19F has been evaluated by computational analysis, and compared to the native repeating unit. The inositol mimic was synthesized, and its experimental spectroscopic data allowed for verification of the theoretical results.
      Graphical abstract image

      PubDate: 2017-03-15T16:35:07Z
       
  • N-Substituted 5-amino-1-hydroxymethyl-cyclopentanetriols: A new family of
           activity promotors for a GM1-gangliosidosis related human lysosomal
           β-galactosidase mutant
    • Abstract: Publication date: Available online 11 March 2017
      Source:Carbohydrate Research
      Author(s): Michael Schalli, Christina Tysoe, Roland Fischer, Bettina M. Pabst, Martin Thonhofer, Eduard Paschke, Tanja Rappitsch, Arnold E. Stütz, Marion Tschernutter, Werner Windischhofer, Stephen G. Withers
      From 1,2;3,4-di-O-isopropylidene-α-D-galactopyranose, a series of highly functionalized (hydroxymethyl)cyclopentanes was easily available. In line with reports by Reymond and Jäger on similar structures, these amine containing basic carbasugars are potent inhibitors of β-D-galactosidases and, for the first time, could be shown to act as pharmacological chaperones for GM1-gangliosidosis-associated lysosomal acid β-galactosidase mutant R201C, thus representing a new structural type of pharmacological chaperones for this lysosomal storage disease.
      Graphical abstract image

      PubDate: 2017-03-15T16:35:07Z
       
  • Stereoselective acetylation of hemicellulosic C5-sugars
    • Abstract: Publication date: Available online 10 March 2017
      Source:Carbohydrate Research
      Author(s): Zachary D. Herde, Prathap John, Dania Alvarez-Fonseca, Jagannadh Satyavolu, Christopher T. Burns
      The stereoselective peracetylation of α-D-xylose (1) and α-L-arabinose (4) using a combination of triethylamine and acetic anhydride in the presence or absence of a catalytic amount of dimethylaminopyridine (DMAP) is described. The peracetylated D-xylose and L-arabinose alpha pyranose anomers 2α and 5α are obtained in 97% and 56% yields respectively. The peracetylated D-xylose beta pyranose anomer 2β is obtained in 71% yield through simple modification of the reaction conditions. Details regarding synthesis and isolation optimization studies under different conditions are presented below. The stereoselective peracetylation reactions disclosed here have been used to separate mixtures of D-xylose and L-arabinose as their peracetylated derivatives 2β and 5α in 47% and 42% yields and can provide pure pentoses after deacetylation.
      Graphical abstract image

      PubDate: 2017-03-15T16:35:07Z
       
  • A Morita-Baylis-Hillman based route to C-5a-chain-extended
           4-epi-isofagomine type glycosidase inhibitors
    • Abstract: Publication date: Available online 6 March 2017
      Source:Carbohydrate Research
      Author(s): René Lebl, Martin Thonhofer, Christina Tysoe, Bettina M. Pabst, Michael Schalli, Patrick Weber, Eduard Paschke, Arnold E. Stütz, Marion Tschernutter, Werner Windischhofer, Stephen G. Withers
      By Morita-Baylis-Hillman reaction of 2,3-O-isopropylidene-D-glyceraldehyde with α,β-unsaturated carbonyl as well as hetero analogous carbonyl compounds such as acrylonitrile, suitable precursors of isofagomine and of 4-epi-isofagomine are available. Elaboration of the structures by amine introduction, followed by intramolecular ring closure and subsequent hydroboration of the double bond provides 4-epi-isofagomine derivatives featuring chain extensions at C-5a which are determined by the structures of the carbonyl compounds employed. As an example, the synthesis of C-(5aR)- and C-(5aS)-5a-C-pentyl-4-epi-isofagomines, powerful inhibitors of β-galactosidases, is outlined. In line with reported data, the (C-5aR) epimer was found a highly potent experimental pharmacological chaperone for GM1-associated human lysosomal β-galactosidase mutant R201C.
      Graphical abstract image

      PubDate: 2017-03-08T11:04:32Z
       
  • Synthesis and biological activities of C-glycosides of KRN 7000 with novel
           ceramide residues
    • Abstract: Publication date: Available online 6 March 2017
      Source:Carbohydrate Research
      Author(s): Ahmad S. Altiti, Xiaojing Ma, Lixing Zhang, Yi Ban, Richard W. Franck, David R. Mootoo
      The identification of immunoactive agents for clinical and mechanistic applications is a very active area of research. In this vein, analogues of the potent immunostimulant KRN 7000 with diverse cytokine profiles have attracted considerable attention. Herein, we report on the synthesis and activity for four new C-glycosides of KRN 7000, 11-phenylundecanoyl and 11-p-fluorophenylundecanoyl derivatives of C-KRN 7000, 2,3-bis-epi-C-KRN 7000 and the reverse amide of C-KRN 7000. In mice, compared to C-KRN 7000, 2,3-bis-epi-C-KRN 7000 stimulated higher release of the anti-inflammatory cytokine IL-4 and lower release of the inflammatory cytokines IFN-γ and IL-12. The phenyl terminated alkanoyl and reverse amide analogues were inactive. These data suggest that structure activity effects for KRN 7000 are not necessarily additive and their use in the design of new analogues will require an improved understanding of how subtle structural changes impact on cytokine activity.
      Graphical abstract image

      PubDate: 2017-03-08T11:04:32Z
       
  • Synthesis of a disaccharide repeating unit of the O-antigen from
           Burkholderia ambifaria and its oligomers
    • Abstract: Publication date: Available online 6 March 2017
      Source:Carbohydrate Research
      Author(s): Dongyue Wang, Weiwei Zhu-Ge, Zhongwu Guo, Guofeng Gu
      A disaccharide repeating unit of the O-antigen from Burkholderia ambifaria, 6-deoxy-β-D-Alt-(1 → 4)-α-D-Rha-O(CH2)3NH2 (1), and its dimer and trimer, 6-deoxy-β-D-Alt-(1 → 4)-α-D-Rha-(1 → 3)-6-deoxy-β-D-Alt-(1 → 4)-α-D-Rha-O(CH2)3NH2 (2) and 6-deoxy-β-D-Alt-(1 → 4)-α-D-Rha-(1 → 3)-6-deoxy-β-D-Alt-(1 → 4)-α-D-Rha-(1 → 3)-6-deoxy-β-D-Alt-(1 → 4)-α-D-Rha-O(CH2)3NH2 (3), were synthesized via a convergent strategy. The key disaccharyl thioglycoside 4 as a glycosyl donor was stereoselectively assembled by glycosylation of rhammnosyl acceptor 5 with 6-deoxy-altrosyl trichloroacetimidate donor 6b. The glycosidation of 4 with 3-azidopropanol followed by global deprotection afforded the target disaccharide 1. Further elongation of the carbohydrate chain of this glycosidation product with the disaccharyl donor 4 followed by global deprotection generated rapidly the dimeric tetrasaccharide 2 and the trimeric hexasaccharide 3 in a convergent [2 + 2] and [2 + 2 + 2] manner, respectively.
      Graphical abstract image

      PubDate: 2017-03-08T11:04:32Z
       
  • RP-UHPLC-UV-ESI-MS/MS analysis of LPMO generated C4-oxidized
           
    • Abstract: Publication date: Available online 6 March 2017
      Source:Carbohydrate Research
      Author(s): Matthias Frommhagen, Gijs van Erven, Mark Sanders, Willem J.H. van Berkel, Mirjam A. Kabel, Harry Gruppen
      Lytic polysaccharide monooxygenases (LPMOs) are able to cleave recalcitrant polysaccharides, such as cellulose, by oxidizing the C1 and/or C4 atoms. The analysis of the resulting products requires a variety of analytical techniques. Up to now, these techniques mainly focused on the identification of non-oxidized and C1-oxidized oligosaccharides. The analysis of C4-oxidized gluco-oligosaccharides is mostly performed by using high pressure anion exchange chromatography (HPAEC). However, the alkaline conditions used during HPAEC analysis lead to tautomerization of C4-oxidized gluco-oligosaccharides, which limits the use of this technique. Here, we describe the use of reverse phase-ultra high performance liquid chromatography (RP-UHPLC) in combination with non-reductive 2-aminobenzamide (2-AB) labeling. Non-reductive 2-AB labeling enabled separation of C4-oxidized gluco-oligosaccharides from their non-oxidized counterparts. Moreover, RP-UHPLC does not require buffered mobile phases, which reduce mass spectrometry (MS) sensitivity. The latter is seen as an advantage over other techniques such as hydrophilic interaction liquid chromatography and porous graphitized carbon coupled to MS. RP-UHPLC coupled to UV detection and mass spectrometry allowed the identification of both labeled non-oxidized and C4-oxidized oligosaccharides. Non-reductive labeling kept the ketone at the C4-position of LPMO oxidized oligosaccharides intact, while selective reducing agents such as sodium triacetoxyborohydride (STAB) reduced this ketone group. Our results show that RP-UHPLC-UV-ESI-MS in combination with non-reductively 2-AB labeling is a suitable technique for the separation and identification of LPMO-generated C4-oxidized gluco-oligosaccharides.
      Graphical abstract image

      PubDate: 2017-03-08T11:04:32Z
       
  • Structural studies of Neurospora crassa LPMO9D and redox partner CDHIIA
           using neutron crystallography and small-angle scattering
    • Abstract: Publication date: Available online 4 March 2017
      Source:Carbohydrate Research
      Author(s): Annette M. Bodenheimer, William B. O'Dell, Christopher B. Stanley, Flora Meilleur
      Sensitivity to hydrogen/deuterium and lack of observable radiation damage makes cold neutrons an ideal probe for the structural studies of proteins with highly photosensitive groups such as the copper center of lytic polysaccharide monooxygenases (LPMOs) and flavin adenine dinucleotide (FAD) and heme redox cofactors of cellobiose dehydrogenases (CDHs). Here, neutron crystallography and small-angle neutron scattering are used to investigate Neurospora crassa LMPO9D (NcLPMO9D) and CDHIIA (NcCDHIIA), respectively. The presence of LPMO greatly enhances the efficiency of commercial glycoside hydrolase cocktails in the depolymerization of cellulose. LPMOs can receive electrons from CDHs to activate molecular dioxygen for the oxidation of cellulose resulting in chain cleavage and disruption of local crystallinity. Using neutron protein crystallography, the hydrogen/deuterium atoms of NcLPMO9D could be located throughout the structure. At the copper active site, the protonation states of the side chains of His1, His84, His157 and Tyr168, and the orientation of water molecules could be determined. Small-angle neutron scattering measurements provided low resolution models of NcCDHIIA with both the dehydrogenase and cytochrome domains in oxidized states that exhibited elongated conformations. This work demonstrates the suitability of neutron diffraction and scattering for characterizing enzymes critical to oxidative cellulose deconstruction.
      Graphical abstract image

      PubDate: 2017-03-08T11:04:32Z
       
  • Novel substrates for the automated and manual assay of
           endo-1,4-β-xylanase
    • Abstract: Publication date: Available online 4 March 2017
      Source:Carbohydrate Research
      Author(s): David Mangan, Claudio Cornaggia, Agnija Liadova, Niall McCormack, Ruth Ivory, Vincent A. McKie, Aaron Ormerod, Barry V. McCleary
      endo-1,4-β-Xylanase (EC 3.2.1.8) is employed across a broad range of industries including animal feed, brewing, baking, biofuels, detergents and pulp (paper). Despite its importance, a rapid, reliable, reproducible, automatable assay for this enzyme that is based on the use of a chemically defined substrate has not been described to date. Reported herein is a new enzyme coupled assay procedure, termed the XylX6 assay, that employs a novel substrate, namely 4,6-O-(3-ketobutylidene)-4-nitrophenyl-β-45-O-glucosyl-xylopentaoside. The development of the substrate and associated assay is discussed here and the relationship between the activity values obtained with the XylX6 assay versus traditional reducing sugar assays and its specificity and reproducibility were thoroughly investigated.
      Graphical abstract image

      PubDate: 2017-03-08T11:04:32Z
       
  • Stereoselective total synthesis of Oxylipin from open chain
           gluco-configured building block
    • Abstract: Publication date: Available online 3 March 2017
      Source:Carbohydrate Research
      Author(s): Santosh Ramdas Borkar, Indrapal Singh Aidhen
      Total synthesis of naturally occurring Oxylipin has been achieved from open chain gluco-configured building block which is readily assembled from inexpensive and commercially available D-(+)-gluconolactone. Grignard reaction and Wittig olefination reactions are key steps for the requisite CC bond formation.
      Graphical abstract image

      PubDate: 2017-03-08T11:04:32Z
       
  • Structural and genetic characterization of the O-antigen of Enterobacter
           cloacae C5529 related to the O-antigen of E. cloacae G3054
    • Abstract: Publication date: Available online 28 February 2017
      Source:Carbohydrate Research
      Author(s): Runhua Han, Andrei V. Perepelov, Yuanyuan Wang, Andrei V. Filatov, Min Wang, Alexander S. Shashkov, Lei Wang, Yuriy A. Knirel
      On mild acid degradation of the lipopolysaccharide of Enterobacter cloacae C5529, the O-polysaccharide chain was cleaved at the linkages of 5,7-diacetamido-3,5,7,9-tetradeoxy-l-glycero-l-manno-non-2-ulosonic acid (di-N-acetylpseudaminic acid, Pse5Ac7Ac). The resultant oligosaccharide and an alkali-treated lipopolysaccharide were studied by sugar analysis along with 1H and 13C NMR spectroscopy, and the following structure of the tetrasaccharide repeating unit of the O-polysaccharide was established: →4)-β-Pse5Ac7Ac-(2 → 3)-β-d-Galp-(1 → 6)-β-d-Galf-(1 → 3)-α-d-Galp-(1→ It differs from a structurally related O-polysaccharide of E. cloacae G3045 studied early (Perepelov, A. V.; Wang, M.; Filatov, A. V.; Guo, X.; Shashkov, A. S.; Wang, L.; Knirel, Y. A. Carbohydr. Res. 2015; 407:59–62) in positions of substitution of β-Psep5Ac7Ac (O-4 vs. O-8) and β-Galp (O-3 vs. O-6) and the absence of a side-chain α-Galp residue. The O-antigen gene clusters of E. cloacae C5529 and G3045 are organized identically and include genes with the same putative functions in the O-polysaccharide synthesis. Based on these and serological data, it is suggested to combine E. cloacae C5529 and G3054 in one O-serogroup as two subgroups.
      Graphical abstract image

      PubDate: 2017-03-01T17:07:47Z
       
  • Total syntheses of Prelactone V and Prelactone B
    • Abstract: Publication date: Available online 28 February 2017
      Source:Carbohydrate Research
      Author(s): S. Raghavendra, Krishnaji Tadiparthi, J.S. Yadav
      The total syntheses of natural products Prelactone–V and Prelactone–B have been accomplished by a novel Chiron approach starting from D–glucose. The synthesis involves isopropylidene acetal formation of D-glucose using Poly(4-vinylpyridine) supported iodine as a catalyst, Tebbe olefination, Grignard reaction, Wittig olefination, selective mono deprotection of acetal using PMA/SiO2, hydrogenation and anti-1,3-diol formation are as key steps.
      Graphical abstract image

      PubDate: 2017-03-01T17:07:47Z
       
  • Synthesis and cytotoxicity of oleanolic acid trisaccharide saponins
    • Abstract: Publication date: Available online 28 February 2017
      Source:Carbohydrate Research
      Author(s): Liming Wang, Zengshang Wang, Sheng Su, Ying Xing, Yali Li, Ming Li, Jiangyun Liu, Shilin Yang
      An array of oleanolic acid-type saponins based on β-hederin has been synthesized in a linear or one-pot manner. The cell viability assays indicate that synthetic saponins show antiproliferation activities in three cancer cell lines with IC50 values of 2.4–15.1 μM and hederacolchiside A1 being the most potent. The results demonstrate that the type of terminal monosaccharides and linkage position have apparent effects on cytotoxicities and selectivities of these saponins against cancer cell lines tested. This study is helpful for future development of more potent anticancer leads.
      Graphical abstract image

      PubDate: 2017-03-01T17:07:47Z
       
  • High yield production of Rhizobium NodB chitin deacetylase and its use for
           in vitro synthesis of lipo-chitinoligosaccharide precursors
    • Abstract: Publication date: Available online 27 February 2017
      Source:Carbohydrate Research
      Author(s): Rémi Chambon, Stéphanie Pradeau, Sébastien Fort, Sylvain Cottaz, Sylvie Armand
      Lipo-chitinoligosaccharides (LCOs) are key molecules for the establishment of plant-microorganisms symbiosis. Interactions of leguminous crops with nitrogen-fixing rhizobial bacteria involve Nod factors, while Myc-LCOs improve the association of most plants with arbuscular mycorrhizal fungi. Both Nod factors and Myc-LCOs are composed of a chitinoligosaccharide fatty acylated at the non-reducing end accompanied with various substituting groups. One straightforward way to access LCOs is starting from chitin hydrolysate, an abundant polysaccharide found in crustacean shells, followed by regioselective enzymatic cleavage of an acetyl group from the non-reducing end of chitin tetra- or pentaose, and subsequent chemical introduction of N-acyl group. In the present work, we describe the in vitro synthesis of LCO precursors on preparative scale. To this end, Sinorhizobium meliloti chitin deacetylase NodB was produced in high yield in E. coli as a thioredoxin fusion protein. The recombinant enzyme was expressed in soluble and catalytically active form and used as an efficient biocatalyst for N-deacetylation of chitin tetra- and pentaose.
      Graphical abstract image

      PubDate: 2017-03-01T17:07:47Z
       
  • Direct, microwave-assisted substitution of anomeric nitrate-esters
    • Abstract: Publication date: Available online 24 February 2017
      Source:Carbohydrate Research
      Author(s): D. Jamin Keith, Steven D. Townsend
      A series of carbohydrate 2-azido-1-nitrate-esters, protected at the C-3, C-4, and C-6 positions, were hydrolyzed thermally, under reagent free conditions. This preliminary result was extended to direct exchange of the 1-nitrate-ester modality for alcohol, alkoxy, and azide coupling partners with minimal purification. While direct glycosylation of nitrate esters ultimately proved unsuccessful, we have demonstrated that an anomeric nitrate-ester can be converted directly to a trichloroacetimidate in a short and simple one-pot procedure, bypassing lower-yielding two-step sequences.
      Graphical abstract image

      PubDate: 2017-03-01T17:07:47Z
       
  • Graphical contents list
    • Abstract: Publication date: 22 February–15 March 2017
      Source:Carbohydrate Research, Volumes 440–441


      PubDate: 2017-03-01T17:07:47Z
       
  • Hydrothermal conversion of N-acetyl-d-glucosamine to
           5-hydroxymethylfurfural using ionic liquid as a recycled catalyst in a
           water-dimethyl sulfoxide mixture
    • Abstract: Publication date: Available online 11 February 2017
      Source:Carbohydrate Research
      Author(s): Hongjun Zang, Songbai Yu, Pengfei Yu, Hongying Ding, Yannan Du, Yuchan Yang, Yiwen Zhang
      Here, N-acetyl-d-glucosamine (GlcNAc), the monomer composing the second most abundant biopolymer, chitin, was efficiently converted into 5-hydroxymethylfurfural (5-HMF) using ionic liquid (IL) catalysts in a water/dimethyl sulfoxide (DMSO) mixture solvent. Various reaction parameters, including reaction temperature and time, DMSO/water mass ratios and catalyst dosage were optimized. A series of ILs with different structures were analyzed to explore their impact on GlcNAc conversion. The substrate scope was expanded from GlcNAc to d-glucosamine, chitin, chitosan and monosaccharides, although 5-HMF yields obtained from polymers and other monosaccharides were generally lower than those from GlcNAc. Moreover, the IL N-methylimidazolium hydrogen sulfate ([Hmim][HSO4]) exhibited the best catalyst performance (64.6% yield) when GlcNAc was dehydrated in a DMSO/water mixture at 180 °C for 6 h without the addition of extra catalysts. To summarize, these results could provide knowledge essential to the production of valuable chemicals that are derived from renewable marine resources and benefit biofuel-related applications.
      Graphical abstract image

      PubDate: 2017-02-15T17:15:12Z
       
  • Structural analysis of rebaudioside A derivatives obtained by
           Lactobacillus reuteri 180 glucansucrase-catalyzed trans-α-glucosylation
    • Abstract: Publication date: Available online 31 January 2017
      Source:Carbohydrate Research
      Author(s): Gerrit J. Gerwig, Evelien M. te Poele, Lubbert Dijkhuizen, Johannis P. Kamerling
      The wild-type Gtf180-ΔN glucansucrase enzyme from Lactobacillus reuteri 180 was found to catalyze the α-glucosylation of the steviol glycoside rebaudioside A, using sucrose as glucosyl donor in a transglucosylation process. Structural analysis of the formed products by MALDI-TOF mass spectrometry, methylation analysis and NMR spectroscopy showed that rebaudioside A is specifically α-D-glucosylated at the steviol C-19 β-D-glucosyl moiety (55% conversion). The main product is a mono-(α1 → 6)-glucosylated derivative (RebA-G1). A series of minor products, up to the incorporation of eight glucose residues, comprise elongations of RebA-G1 with mainly alternating (α1 → 3)- and (α1 → 6)-linked glucopyranose residues. These studies were carried out in the context of a program directed to the improvement of the taste of steviol glycosides via enzymatic modification of their naturally occurring carbohydrate moieties.
      Graphical abstract image

      PubDate: 2017-02-03T03:35:18Z
       
  • C-5a-substituted validamine type glycosidase inhibitors
    • Abstract: Publication date: Available online 13 January 2017
      Source:Carbohydrate Research
      Author(s): Michael Schalli, Andreas Wolfsgruber, Andres Gonzalez Santana, Christina Tysoe, Roland Fischer, Arnold E. Stütz, Martin Thonhofer, Stephen G. Withers
      A series of N-alkyl derivatives of the D-galactosidase inhibitor 1,4-di-epi-validamine featuring lipophilic substituents at position C-5a was prepared and screened for their glycosidase inhibitory properties. Products turned out selective for β-galactosidases as well as β-glucosidases.
      Graphical abstract image

      PubDate: 2017-01-21T09:02:46Z
       
  • Large scale synthesis and regioselective protection schemes of ethyl
           2-azido-2-deoxy-1-thio-α-D-cellobioside for preparation of heparin
           thiodisaccharide building blocks
    • Abstract: Publication date: Available online 11 January 2017
      Source:Carbohydrate Research
      Author(s): Kevin Sheerin, Lorenzo Guazzelli, Stefan Oscarson
      Crystalline acetylated ethyl 2-azido-2-deoxy-1-thio-α-d-cellobioside has been prepared on a multigram scale from cellobiose in an overall yield of 23% with no chromatography required and converted after deacetylation into the 4′,6′-O-benzylidene and 4′,6′-O-benzylidene-6-O-TBDMS protected derivatives. Applying a number of regioselective benzylation methods on these gave access to a variety of regioselectively protected derivatives, both mono-ols (2′- and 3-OH), diols (2′,6-, 2′,3-, and 3,6-di-OH), and triols (2′,3,6- and 2′,3′,3-tri-OH). A number of these derivatives were further processed by benzoylation followed by removal or opening of the benzylidene acetal and selective oxidation of the exposed primary alcohol to give heparin building block intermediates comprising a range of possible sulfation patterns.
      Graphical abstract image

      PubDate: 2017-01-13T08:43:52Z
       
  • The structure of the LPS O-chain of Fusobacterium nucleatum strain 25586
           containing two novel monosaccharides, 2-acetamido-2,6-dideoxy-l-altrose
           and a 5-acetimidoylamino-3,5,9-trideoxy-gluco-non-2-ulosonic acid
    • Abstract: Publication date: Available online 9 January 2017
      Source:Carbohydrate Research
      Author(s): Evgeny Vinogradov, Frank St. Michael, Andrew D. Cox
      Fusobacterium nucleatum is an anaerobic bacterium found in the human mouth where it causes periodontitis. Recently, it has been gaining attention as a potential causative agent for colorectal cancer and is strongly linked with pregnancy complications including pre-term and still births. Little is known about the virulence factors of this organism, and thus we have initiated studies to examine the bacterium's surface glycochemistry. We isolated lipopolysaccharide (LPS) from F. nucleatum strain 25586 and purified and performed structural analysis on the O-antigen polysaccharide. The polysaccharide contained two novel sugars, 2-acetamido-2,6-dideoxy-l-altrose (l-6dAltNAc) and a 5-acetimidoylamino-3,5,9-trideoxy-gluco-non-2-ulosonic acid (Non5Am), which was tentatively assigned the l -glycero- l -gluco configuration. The polysaccharide was found to have a trisaccharide repeating unit, which is phosphorylated with phosphocholine (PCho), and the following structure was established: -[-4-β-Nonp5Am-4-α-l-6dAltpNAc3PCho-3-β-d-QuipNAc-]- We propose the trivial name ‘fusaminic acid’ for the novel nonulosonic acid. It is the first occurrence of a 9-deoxynonulosonic acid with a hydroxyl group at C-7, which is occupied by an amino group in all monosaccharides of this class described so far.
      Graphical abstract image

      PubDate: 2017-01-13T08:43:52Z
       
 
 
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