D-glucose Residues Research Articles

A Histological and Histochemical Study of Posterior Lingual Gland in Japanese Monkey (Macaca fuscata)

Although several studies of salivary glands in the mammals, including monkeys, have been reported, many of them are about major salivary glands, and analyses of minor salivary gland are little. Therefore, the present study performed a histological and histochemical study in order to clarify the posterior lingual gland in monkeys, and to obtain the fundamental findings for comparative study with salivary gland diseases. Lingual tissues were obtained from five adult Japanese monkeys (Macaca fuscata). All the specimens were fixed in 10% neutral formalin solution as soon as those had been removed, and then, paraffin sections were made. The sections were stained with hematoxylin-eosin and PAS-alcian blue pH 2.5. The avidin-biotin-peroxidase complex and direct fluorescence methods using seven kinds of lectin were performed in the present study. Front and back zone of the posterior lingual glands consisted of different type of the acinar cells. The front zone was predominantly composed of PAS-positive acinar cells indicating serous characteristics, whereas back zone mainly consisted of the acinar cells stained with alcian blue pH 2.5 showing mucous characteristics. Serous acinar cells showed positive reactivities for Con A, WGA, RCA-I and UEA-I, whereas DBA was negative. Mucous acinar cells were positive for WGA, RCA-I and UEA-I, but Con A was negative. After neuraminidase digestion, positive reactivities for WGA and PNA were higher in the serous acinar cells compared to non-digestion. These results suggested that the serous cells predominantly contained D-mannose, D-glucose, N-acetyl-D-glucosamine, N-acetyl neuraminic acid, D-galactose and L-fucose residues, whereas the mucous acinar cells had similar sugar residues with the serous acinar cells except for D-mannose and D-glucose residues. Furthermore, the result of neuraminidase digestion suggested that the serous acinar cells mainly contained not only N-acetyl neuraminic acid but also N-acetyl-D-glucosamine and D-galactose residues.

Structural elucidation of an exopolysaccharide from mycelial fermentation of a Tolypocladium sp. fungus isolated from wild Cordyceps sinensis

A novel polysaccharide designated EPS-1A with an average molecular weight around 40 kDa was fractionated and purified by anion-exchange and gel-filtration chromatography from the crude exopolysaccharide (EPS) isolated from fermentation broth of Cs-HK1, a Tolypocladium sp. fungus isolated from wild Cordyceps sinensis. The structural characteristics of EPS-1A were determined with various methods (e.g. GC, GC–MS, FT-IR, 1H NMR and 13C NMR) and through acid hydrolysis, methylation, periodate-oxidation and Smith degradation. The results suggested that EPS-1A was composed of glucose, mannose and galactose at 15.2:3.6:1.0 M ratio. EPS-1A was a slightly branched polysaccharide and its backbone was composed of (1 → 6)-α- d-glucose residues (∼77%) and (1 → 6)-α- d-mannose residues (∼23%). Branching occurred at O-3 position of (1 → 6)-α- d-mannose residues of the backbone with (1 → 6)-α- d-mannose residues and (1 → 6)-α- d-glucose residues, and terminated with β- d-galactose residues.

Purification, structure and immunobiological activity of a water-soluble polysaccharide from the fruiting body of Pleurotus ostreatus

The water-soluble polysaccharide (POP), with a molecular mass of 2.4×104Da, was obtained from the fruiting body of Pleurotus ostreatus. Structure features of the purified polysaccharide were investigated by a combination of chemical and instrumental analysis, such as methylation analysis, Smith degradation, GC-MS, 13C and 1H NMR and FTIR. The results indicated that the backbone of POP was composed of (1→6)-linked-α-d-galactopyranosyl and (1→2,6)-linked-α-d-galactopyranosyl residues, which were terminated with a single terminal (1→)-β-d-glucose residue at the O-2 position of galactosyl along the main chain in the ratio of 1:1:1. Preliminary tests in vitro showed POP is capable of enhancing concanavalin A (ConA)- or lipopolysaccharide (LPS)-induced lymphocyte proliferation, which suggested that POP could be a potential immunostimulating agent for use in functional foods or medicine against both pathogens and cancer.

Structural elucidation and biological activity of a novel polysaccharide by alkaline extraction from cultured Cordyceps militaris

A novel polysaccharide named CBP-1 was isolated from the fruiting body of cultured Cordyceps militaris by alkaline extraction as well as anion-exchange and gel-permeation chromatography. Its structural features were investigated by a combination of chemical and instrumental analysis approaches, including partial hydrolysis, methylation analysis, HIO 4 oxidation-Smith degradation, GC–MS, 13C NMR, HPAEC-PAD and FT-IR. The results indicated that CBP-1 has a backbone of (1 → 4)-α- d-mannose residues which occasionally branches at O-3. The branches were mainly composed of (1 → 4)-α- d-glucose residues and (1 → 6)-β- d-galactose residues, and terminated with β- d-galactose residues. In the in vitro antioxidant assay, CBP-1 was found to possess the hydroxyl radical-scavenging activity with an IC 50 value of 0.638 mg/ml.

Morphological and structural characterization of a polysaccharide from Gynostemma pentaphyllum Makino and its anti-exercise fatigue activity

The crude polysaccharide was obtained from Gynostemma pentaphyllum Makino by water extraction followed by ethanol precipitation. The polysaccharide was successively purified by chromatography on DEAE-52 and SephadexG-150 column, and three polysaccharide fractions were obtained and termed GPP1-a, GPP2-b, and GPP3-a, respectively. The administration with GPP1-a markedly prolonged exhaustive exercise time of the mice. Structural features of GPP1-a were investigated by a combination of instrumental and chemical analyses, including atomic force microscope (AFM), scanning electron microscope (SEM), partial acid hydrolysis, periodate oxidation, Smith degradation, methylation analysis, gas chromatography–mass spectrometry (GC–MS) analysis and NMR spectroscopy. The results indicate that GPP1-a has a backbone of (1 → 4)-linked α- d-Glucose residues, which occasionally branches at O-6. The branches are mainly composed of (1 → 6)-linked α- d-Glucose, (1 → 3)-linked β- d-Galactose and (1 → 6)-linked α- d-Galactose residues, and terminated with β- d-Galactose residues and β- l-Arabinose residues.

Development of a 1H NMR structural-reporter-group concept for the primary structural characterisation of α- d-glucans

An NMR study of proton chemical shift patterns of known linear α- d-glucopyranose di- and trisaccharide structures was carried out. Chemical shift patterns for (α1→2)-, (α1→3)-, (α1→4)- and (α1→6)-linked d-glucose residues were analysed and compared to literature data. Using these data, a 1H NMR structural-reporter-group concept was formulated to function as a tool in the structural analysis of α- d-glucans.

Structural characterization and serological specificities of lipopolysaccharides from Salmonella enterica serovar Gallinarum biovar Pullorum standard, intermediate and variant antigenic type strains

The structure and serological specificities of the lipopolysaccharides (LPSs) from Salmonella enterica serovar Gallinarum biovar Pullorum were studied to provide an improved basis for the distinction between antigenic types and the development of improved diagnostic tests. The structure of the LPS O-polysaccharide (O-PS) from S. Pullorum standard, intermediate and variant antigenic type strains was determined by mass spectrometry, nuclear magnetic resonance spectroscopy and chemical analysis. The LPS of the three strains shared a common structural repeating oligosaccharide unit containing d-mannose, l-rhamnose, d-galactose and d-tyvelose (1:1:1:1). The O-PS of the variant type LPS contained an additional d-glucose residue linked to the O-4 position of the d-galactose residue. The O-PS of the intermediate type LPS was partially the same as that of the variant LPS, however, the molar ratio of the d-glucose component was lower with respect to the other glycose components. Serological specificities of the three antigenic type LPSs were examined with anti- S. Pullorum LPS monoclonal antibodies (Mabs). On immunoblots, Mabs to the standard type O-PS reacted with high molecular mass (HMM) and low molecular mass (LMM) LPS from the standard strain, and with LMM but not HMM LPS from the variant strain. Monoclonal antibodies to the variant type O-PS reacted with HMM but not LMM LPS from the variant strain, and did not react with HMM or LMM LPS from the standard strain. On ELISA, the standard, intermediate and variant antigenic type strains were differentiated by the relative reactivity with the anti-LPS O-PS Mabs. Several of the anti-LPS O-PS Mabs were specific for S. Pullorum and other serogroup D1 Salmonella, and are potentially useful for the development of improved diagnostic tests for these organisms.

The structure of the glycerophosphate-containing O-specific polysaccharide from Escherichia coli O130

A phosphorylated O-specific polysaccharide was obtained by mild acidic degradation of the lipopolysaccharide from the intestinal bacterium Escherichia coli 0130 and characterized by the methods of chemical analysis, including dephosphorylation, and 1H and 13C NMR spectroscopy. The polysaccharide was shown to be composed of branched tetrasaccharide repeating units containing two N-acetyl-D-galactosamine residues, D-galactose, D-glucose, and glycerophosphate residues (one of each). The polysaccharide has the following structure, which is unique among the known bacterial polysaccharides.

Cell wall mannan of human pathogen Candida dubliniensis

Cell wall mannan isolated and purified from the human pathogen yeast Candida dubliniensis CCY 29-177-1 has been characterized. The polysaccharide of M w = 35,000 was composed of d-mannose and trace amount of d-glucose residues. Compositional and methylation analyses of the polymer, acetolysis as well as 1H and 13C NMR measurements pointed to a highly branched structure of C. dubliniensis mannan. Its backbone was composed of α-1,6-linked mannose residues branched at O-2 by side mannose residues as single stubs, as well as side oligosaccharide chains of d.p. 2–7, mostly in the form of tri-, di- and tetramers. Longer side chains, penta, hexa- and heptamers, were found in lesser amounts. NMR spectra showed that oligosaccharide side chains were formed by α-1,2- and α-1,3-linked mannose residues. In addition, the presence of higher quantity of oligosaccharides with terminal Manβ(1 → 2)Manβ(1 → fragment was deduced on the basis of characteristic signals in the HSQC spectrum of polymer mannan.

Lipopolysaccharides from Pseudomonas maltophilia

Structural studies have been carried out on the O-specific polysaccharide, the core oligosaccharide, and the lipid A from the lipopolysaccharide of Pseudomonas maltophilia NCTC 10257. By means of 13C nuclear magnetic resonance spectroscopy, a tetrasaccharide repeating-unit for the O-specific polymer has been confirmed. However, the data suggest that the L-rhamnopyranosyl residue at the branching point has the alpha configuration rather than beta as proposed previously [Neal, D.J. and Wilkinson, S.G. (1979) Carbohydr. Res. 69, 191-201]. The core oligosaccharide contains residues of D-glucose, D-mannose phosphate, D-galactosamine (not N-acetylated), D-galacturonic acid, and a 3-deoxyoctulosonic acid (but no aldoheptose). A partial structure for the oligosaccharide is proposed. Lipid A is based on phosphorylated glucosamine residues, with N-fatty acyl and O-fatty acyl substituents. The major fatty acids are 9-methyldecanoic acid, 2-hydroxy-9-methyldecanoic acid, 3-hydroxy-9-methyldecanoic acid (each ester-linked), 3-hydroxydodecanoic acid, and 3-hydroxy-11-methyldodecanoic acid (both mainly amide-linked). The results of this study provide further evidence for a relationship between P. maltophilia and some Xanthomonas species.

One-pot synthesis of glycosyl poly(arbutin) by enzymatic glycosylation followed by polymerization with peroxidase

Polyaromatic compounds that carry several side residues of d-glucose, d-galactose, and d-mannose were synthesized from hydroquinone β-glucoside (arbutin) through two successive enzymatic reactions: glycosylation of the glucose residue in arbutin, followed by oxidative polymerization of the hydroquinone moieties. In the first step, Bacillus macerans cyclodextrin glucanotransferase, B. circulans β-galactosidase, and jack bean α-mannosidase were used to obtain glycosylation products in yields of 56.0, 29.5, and 25.2%, respectively, where the main products were a series of α-1,4-linked glucosyl/maltooligosyl arbutin, β-1,4-linked galactosyl arbutin, and α-1,6-linked mannosyl arbutin, respectively. In the second step, horseradish peroxidase was used and the enzyme efficiently polymerized glycosyl arbutin(s) together with the remaining arbutin using hydrogen peroxide as an oxidant. The water-soluble products, glycosyl poly(arbutin)s, showed approximate molecular weight distribution of 0.5–25 kDa which was estimated by gel permeation chromatography calibrated with maltooligosaccharides and pullulan markers. There were no differences in the phenolic main chain structures of glycosyl poly(arbutin)s and poly(arbutin), where the binding of neighboring hydroquinone moieties occurred at ortho-positions. Glycosyl poly(arbutin)s containing α-linked mannose and β-linked galactose residues exhibited increased absorbability to immobilized concanavalin A and castor bean lectin (RCA 120), respectively.

Alternansucrase acceptor reactions with d-tagatose and l-glucose

Alternansucrase (EC 2.4.1.140) is a d-glucansucrase that synthesizes an alternating α-(1→3), (1→6)-linked d-glucan from sucrose. It also synthesizes oligosaccharides via d-glucopyranosyl transfer to various acceptor sugars. Two of the more efficient monosaccharide acceptors are d-tagatose and l-glucose. In the presence of d-tagatose, alternansucrase produced the disaccharide α- d-glucopyranosyl-(1→1)-β- d-tagatopyranose via glucosyl transfer. This disaccharide is analogous to trehalulose. We were unable to isolate a disaccharide product from l-glucose, but the trisaccharide α- d-glucopyranosyl-(1→6)-α- d-glucopyranosyl-(1→4)- l-glucose was isolated and identified. This is analogous to panose, one of the structural units of pullulan, in which the reducing-end d-glucose residue has been replaced by its l-enantiomer. The putative l-glucose disaccharide product, produced by glucoamylase hydrolysis of the trisaccharide, was found to be an acceptor for alternansucrase. The disaccharide, α- d-glucopyranosyl-(1→4)- l-glucose, was a better acceptor than maltose, previously the best known acceptor for alternansucrase. A structure comparison of α- d-glucopyranosyl-(1→4)- l-glucose and maltose was performed through computer modeling to identify common features, which may be important in acceptor affinity by alternansucrase.

Metabolites Produced by Actinomycetes — Antiviral Antibiotics and Enzyme Inhibitors

AbstractFor Abstract see ChemInform Abstract in Full Text.

Inclusion complexes of V-amylose with undecanoic acid and dodecanol at atomic resolution: X-ray structures with cycloamylose containing 26 d-glucoses (cyclohexaicosaose) as host

Crystal structures are reported of cycloamylose containing 26 d-glucose residues (CA26, cyclohexaicosaose, C 156H 260O 130) in complexes with undecanoic acid (CA26·2C 10H 21COOH·34.95H 2O, orthorhombic P2 12 12 1, one CA26 and two bound undecanoic acids F1 and F2 in the asymmetric unit, resolution 0.95 Å) and with dodecanol ((CA26) 0.5·C 12H 25OH·32.0H 2O, monoclinic C2, half a CA26 binding one dodecanol, A, in the asymmetric unit, resolution 1.0 Å). The macrocycle of CA26 is folded like the figure `8' into two 10 d-glucoses long left-handed V-amylose helices forming ∼5 Å wide V-channels that are occupied by undecanoic acid (F1, F2) or dodecanol (A) as guest molecules. The functional head groups of the guests near the O(6) ends of the V-channels are hydrogen bonded with d-glucose O(6) n –H; the aliphatic termini beyond C(9) protrude from the O(2), O(3) ends. Parts of the aliphatic chains enclosed in the V-channels are all- trans except for one torsion angle each (∼130°) in undecanoic acid molecules F1 and F2. There are several (guest)C–H⋯O hydrogen bonds to O(4) and O(6) of CA26 in both complexes, and H⋯H van der Waals interactions with d-glucose C(3)–H and C(5)–H dominate. C(5)–H determine the position of the aliphatic chains of undecanoic acid F1 and of dodecanol A in contrast to F2 where both C(3)–H and C(5)–H contribute equally, probably because the V-channel is narrower than in F1 and in dodecanol. Complexes of polymeric V-amylose with fatty acids and alcohols studied by X-ray fiber diffraction could not provide the here described high resolution.

Metabolites produced by actinomycetes--antiviral antibiotics and enzyme inhibitors

In 1995, we discovered new antiherpetic antibiotics, called fattiviracins. The producing organism was classified as a strain belonging to Streptomyces microflavus. The strain produced at least 13 fattiviracin derivatives (FV-1 to FV-13). Fattiviracins were obtained as a white amorphous powder, and their molecular weights are in the range of 1400 to 1500. They are readily soluble in water, methanol, pyridine, and DMSO, but insoluble in other organic solvents. Fattiviracins have macrocyclic diesters formed by the binding of two trihydroxy fatty acids and two D-glucose residues in the molecule, and they can be divided into five families according to the length of the fatty acid moiety. Fattiviracins have potent activity against enveloped DNA viruses such as the herpes family, HSV-1, and VZV and enveloped RNA viruses such as influenza A and B viruses, and three strains of HIV-1, with EC(50) values on the order of a few micrograms per milliliter. The biosynthetic pathway of fattiviracins is also becoming clearer. Using bacitracin-resistant strains, enhanced and astringent production of fattiviracin was achieved. Fattiviracin FV-13, which has the longest fatty acid chains in the molecule, was dramatically enhanced by a C(55)-isoprenyl phosphate metabolism. In addition, we have screened various inhibitors of enzymes such as alkaline protease, glucosyltransferase, glucuronidase, phospholipase, deoxyribonuclease, DNA methyltransferase, and DNA topoisomerase. All the inhibitors we discovered are briefly summarized in this paper.

Fattiviracins, Antiviral Antibiotics Produced by an Actinomycete

In 1995, we discovered new antiherpetic antibiotics, called fattiviracins. The producing organism was classified as a strain belonging to Streptomyces microflavus. The strain produced at least 13 fattiviracin derivatives (FV-1 to FV-13). Fattiviracins were obtained as a white amorphous powder, and their molecular weights are in the range of 1400 to 1500. They are readily soluble in water, methanol, pyridine and DMSO, but insoluble in other organic solvents. Fattiviracins have macrocyclic diesters formed by the binding of two trihydroxy fatty acids and two D-glucose residues in the molecule, and they can be divided into 5 families, according to the length of fatty acid moiety. Fattiviracins have a potent activity against enveloped DNA viruses such as the herpes family, HSV-1 and VZV and enveloped RNA viruses such as influenza A and B viruses, and three strains of HIV-1, in the order of a few μg/ml of EC50. The biosynthetic pathway of fattiviracins is also becoming clearer. Using bacitracin-resistant strains, enhanced and astringent production of fattiviracin was recognized: fattiviracin FV-13, having the longest fatty acid chains in the molecule was dramatically enhanced by a C55-isoprenyl phosphate metabolism.

Bacillus macerans cyclomaltodextrin glucanotransferase transglycosylation reactions with different molar ratios of d-glucose and cyclomaltohexaose

It was found that Bacillus macerans cyclomaltodextrin glucanotransferase (CGTase) reacts with cyclomaltohexaose (α-cyclodextrin, α-CD) to give a series of cyclomaltooligosaccharides (cyclomaltodextrins, CDs), having seven to more than 20 d-glucose residues and maltooligosaccharides (maltodextrins, MDs) from G5 to G12+. When d-glucose (Glc) was added to the α-CD at very low molar ratios (1:100) of Glc to α-CD, the predominant products (95%) were CDs, some of which were macrocyclic MDs with 20–60 d-glucose residues, along with MDs that also had high molecular weights, containing 10–75 d-glucose residues and gave a blue iodine–iodide color. As the molar ratio of Glc to α-CD was increased, the amount of CDs progressively decreased and MDs proportionately increased in the range of G2–G12. At 25 mM α-CD and Glc to α-CD molar ratio of 1:1, a 75% yield of MDs, G1–G12, each in approximately equal amounts, was obtained; and at 20 mM and a 5:1 ratio, a 97% yield of MDs, G2–G9, was obtained but in unequal amounts. At higher ratios (10:1), the CDs completely disappeared, and at very high ratios (50:1 to 100:1) only low-molecular-weight MDs, G2–G4, were formed.

Synthesis of well-defined chain-end- and in-chain-functionalized polystyrenes with a definite number of benzyl chloride moieties and D-glucose residues

Novel well-defined chain-end- and in-chain-functionalized polystyrenes with six, eight, twelve, and sixteen benzyl chloride moieties and with four and eight D-glucose residues have been successfully synthesized by developing the methodology based on living anionic polymerization of using new functionalized agents derived from functionalized 1,1-diphenylethylene (DPE) derivatives. They are 1,10-dichloro-4,4-7,7-tetra(3-methoxymethylphenyl)decane, its iodide derivative, the dianion prepared from 1,1-bis(3-methoxymethylphenyl)ethylene and potassium naphthalenide, and 1,1-bis[3',5'-bis(1,2:5,6-di-O-isopropylidene-α-D-glucofuranose-3-oxymethyl)phenyl]ethylene. The developed methodology involves diverse modes of reactions of polystyryllithium with new functionalized agents and either the subsequent transformation reaction with BCl 3 into benzyl chloride moieties or acid-hydrolysis to regenerate D-glucose residues. The resulting chain-multi-functionalized polystyrenes were precisely controlled with respect to chain length and quantitatively functionalized within experimental errors.

Synthesis of Poly(L-lactide) with One Terminal D-Glucose Residue and Wettability of Its Film Surface

To develop the new-type poly(L-lactide)-based biomedical material having a wettable surface, the synthesis of poly(L-lactide) with one terminal D-glucose residue was investigated. After the hydroxyl group at 1-C of α-tetrabenzyl glucose, α-Glc(Bzl)4, was converted to the corresponding potassium alkoxide by using potassium tert-butoxide, L-lactide (L-LA) was polymerized in the presence of α-Glc(Bzl)4-OK as an initiator in tetrahydrofuran at room temperature to prepare α-Glc(Bzl)4-polyLA. Subsequently, the removal of O-protecting benzyl groups in the terminal α-Glc(Bzl)4 residue was carried out by hydrogenolysis with Pd/C to obtain the objective D-glucose-end-capped polyLA, α-Glc-polyLA. The wettability of surface of the α-Glc-polyLA material is discussed using the difference of the dynamic contact angle between a α-Glc-polyLA/homopolyLA blend film and a film of the polyLA homopolymer.

Synthesis of Poly(L-lactide) with One TerminalD-Glucose Residue and Wettability of Its Film Surface

To develop the new-type poly(L-lactide)-based biomedical material having a wettable surface, the synthesis of poly(L-lactide) with one terminal D-glucose residue was investigated. After the hydroxyl group at 1-C of α-tetrabenzyl glucose, α-Glc(Bzl) 4 , was converted to the corresponding potassium alkoxide by using potassium tert-butoxide, L-lactide (L-LA) was polymerized in the presence of α-Glc(Bzl) 4 -OK as an initiator in tetrahydrofuran at room temperature to prepare α-Glc(Bzl) 4 -polyLA. Subsequently, the removal of O-protecting benzyl groups in the terminal α-Glc(Bzl) 4 residue was carried out by hydrogenolysis with Pd/C to obtain the objective D-glucose-end-capped polyLA, α-Glc-polyLA. The wettability of surface of the α-Glc-polyLA material is discussed using the difference of the dynamic contact angle between a α-Glc-polyLA/homopolyLA blend film and a film of the polyLA homopolymer.