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Results 701 - 750 of 1921
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Wang Y - - 1998
The depolymerization of polysaccharides, particularly those containing acid-sensitive components, into intact constituent repeating units can be very difficult. We describe a method using ozonolysis for depolymerizing polysaccharides containing beta-D-aldosidic linkages into short-chain polysaccharides and oligosaccharides. This method is carried out on polysaccharides that have been fully acetylated whereby beta-D-aldosidic linkages ...
Parolis L A - - 1998
The exopolysaccharide produced by Pichia (Hansenula) holstii NRRL Y-2448 is composed of a phosphomannan core to which oligosaccharide diester phosphate side chains are appended. The oligosaccharides of the side chains were released as oligosaccharide phosphates and neutral oligosaccharides by mild hydrolysis with aqueous acetic acid and aqueous hydrogen fluoride, respectively. ...
Grimmecke H D - - 1998
Reductive amination of 3-deoxy-D-manno-octulosonic acid (Kdo) with allylamine (AIIN) or 2-(4-aminophenyl)ethylamine (APEA) yields epimer pairs of 2-N-allylamino and 2-N-[2-(4-aminophenyl)ethylamino]-2,3-dideoxy-D-glycero-D-galacto- and -2,3-dideoxy-D-glycero-D-talo-octonic acid. The yields were 50-60% due to reduction of Kdo to the respective polyols as side reaction products. Mass spectrometric analyses proved the amination derivatives to be the expected ...
Kocharova N A - - 1998
N epsilon-[(R)-1-Carboxyethyl]-L-lysine was released by acid hydrolysis from the O-specific polysaccharide of Providencia alcalifaciens O23 and identified by 1H and 13C NMR spectroscopy, GLC-MS after conversion to a di-N-acetylated dimethyl ester, and by comparison with the authentic sample. Solvolysis of the polysaccharide with anhydrous HF resulted in an amide of ...
Kitazawa H - - 1998
The mitogenic activity of extracellular polysaccharides produced by Lactobacillus delbrueckii ssp. bulgaricus OLL 1073R-1 and NCFB2483 was examined in murine lymphocytes. The extracellular polysaccharide from Lactobacillus delbrueckii ssp. bulgaricus OLL 1073R-1 was fractionated into neutral and acidic polysaccharides by anion-exchange chromatography, while that of Lactobacillus delbrueckii ssp. bulgaricus NCFB2483 were ...
Dieuleveux V - - 1998
Geotrichum candidum excretes D-3-phenyllactic acid, which inhibits the growth of Listeria monocytogenes. It was found to inhibit a range of gram-positive bacteria found in humans and foodstuffs, such as Staphylococcus aureus and Enterococcus faecalis, and gram-negative bacteria from humans, such as Providencia stuartii and Klebsiella oxytoca. Scanning electron microscope studies ...
Süsskind M - - 1998
In a preliminary investigation (Süsskind, M., Müller-Loennies, S., Nimmich, W., Brade, H., and Holst, O. (1995) Carbohydr. Res. 269, C1-C7), we identified after deacylation of lipopolysaccharides (LPS) from Klebsiella pneumoniae ssp. pneumoniae rough strain R20 (O1(-):K20(-)) as a major fraction the oligosaccharide,-structure; see text- where Kdo was 3-deoxy-D-manno-oct-2-ulopyranosonic acid and ...
Kardosova A - - 1998
From the medicinal plant Rudbeckia fulgida, var. sillivantii (Boynton et Beadle) a low-molecular-mass (4-O-methyl-alpha-D-glucurono)-D-xylan was isolated by alkaline extraction, followed by ethanol precipitation, ion-exchange chromatography and gel filtration. The results of compositional and linkage analyses, supported by those of 1H and 13C NMR measurements of oligomers generated on partial acid ...
Amano K I - - 1998
The lipopolysaccharides (LPSs) isolated from typhus group (TG) rickettsiae Rickettsia typhi and Rickettsia prowazekii were characterized by chemical analysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) followed by silver staining. LPSs from two species of TG rickettsiae contained glucose, 3-deoxy-D-manno-octulosonic acid, glucosamine, quinovosamine, phosphate, and fatty acids (beta-hydroxylmyristic acid and ...
Ding Y Q - - 1998
Three fractions of polysaccharides that have high biological activity were extracted from Chinese bamboo leaves (Indocalamus Tesselatus) with 0.9% sodium chloride, 1% ammonium oxalate and 85% ethanol. Their component sugars were investigated by paper chromatography developed with n-butanol-pyridine-water (6:4:3 by vol), and by gas chromatography with crown ester stationary-phase-fused silica ...
Gamian A - - 1998
The structure of the O-specific polysaccharides of the lipopolysaccharides produced by Hafnia alvei strains ATCC 13337 and 1187 was reinvestigated. The position of phosphate group in the repeating units of the polysaccharides was established with the aid of 1H detected, 31P edited NMR spectra. According to the results obtained, the ...
Streshinskaya G M - - 1998
The structures of teichoic acids of three Nocardiopsis species were established. The cell wall of Nocardiopsis listeri VKM Ac-1881T contains two teichoic acids (TA). TA1 is 1,3-poly(glycerol phosphate) with 50% glycerol phosphate residues substituted by alpha-N-acetylglucosamine in the C-2 position. TA2 is 1, 5-poly(ribitol phosphate) with each ribitol phosphate unit ...
Garozzo D - - 1998
The exocellular polysaccharide produced by the cyanobacterium Cyanospira capsulata has been subjected to partial acid hydrolysis and N-deacetylation-nitrous acid deamination. The oligosaccharides released have been isolated by weak anion exchange and aqueous size exclusion chromatography, and characterized by a combination of 1D and 2D nuclear magnetic resonance spectroscopy, mass spectrometry, ...
Hanniffy O M - - 1998
An acidic O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide isolated by phenol-water extraction of Pseudoalteromonas haloplanktis strain KMM 223 (44-1). L-Iduronic acid (IdoA) was found to be a component of the polysaccharide and identified by NMR spectroscopy and after carboxyl-reduction followed by acid hydrolysis and acetylation, ...
Katzenellenbogen E - - 1998
On the basis of chemical analyses and NMR spectroscopic studies, it was found that the O-specific polysaccharide (O-PS) isolated from the Hafnia alvei PCM 1199 lipopolysaccharide (LPS) is a glycerol teichoic-acid-like polymer having a repeating unit of the following structure: [structure in text] where Qui4NAc is 4-acetamido-4,6-dideoxyglucose and O-acetylation at ...
Kim J O - - 1998
The pneumococcus undergoes spontaneous phase variation between an opaque and a transparent colony form. In an animal model of systemic infection following intraperitoneal inoculation of mice, the opaque phenotype was significantly more virulent than the transparent for each of 3 strains examined. The opaque phenotype was associated with 1.2- to ...
Xavier Da Silveira E - - 1998
We have characterized glycoinositol phospholipids (GIPLs) from three strains of the trypanosomatid parasites Endotrypanum schaudinni and Endotrypanum monterogeii. Methanolysis of the intact GIPLs liberated methyl esters of tetracosanoic acid, docosanoic acid, octadecanoic acid and hexadecanoic acid and C20 and C21 phytosphingosines. Phosphoinositol oligosaccharides were released from the GIPLs by mild ...
Velasco J - - 1998
A degradation protocol using de-O-acylation and subsequent alkaline de-N-acylation was applied to the lipopolysaccharide of Ochrobactrum anthropi rough strain LMG 3301. Three main oligosaccharide bisphosphates containing core-lipid A backbone structures were obtained after fractionation by anion-exchange HPLC. Using 1H and 13C NMR spectroscopy, including two-dimensional COSY, TOCSY, and NOE spectroscopy ...
Nichifor M - - 1998
Dextran, pullulan, and microcrystalline cellulose were cross-linked with 1-chloro-2,3-epoxypropane and reacted with N-(1-chloroethyl)-N,N-diethylamine or N-glycidyl-N,N,N-trialkylammonium chloride in order to obtain sorbents containing tertiary amino and/or quaternary ammonium groups. In vitro equilibrium sorption of cholic acid on these sorbents was studied in comparison with Cholestyramine, and in vitro dissociation of ionic ...
Zheng Z - - 1998
Using a large-scale culture technique, the hairy roots of Astragalus membranaceus were produced with a yield reaching 10 g/L. The results from RP-HPLC detection showed that the contents of crude saponin and astragaloside i.v. in the hairy roots were 5.81% and 0.14%, respectively. Six isoflavonoid compounds were also determined. Polysaccharide ...
Crotti L B - - 1998
The exo-1 mutant of Neurospora crassa produced and secreted pectolytic activities when incubated in the presence of pectin-containing biological materials. This study shows that polygalacturonase, pectate lyase and pectin lyase activities were induced in media supplemented with galactose or galacturonic acid, indicating that these sugars induced the synthesis of pectinases. ...
Shashkov A S - - 1998
The O-specific polysaccharide of Pseudomonas fluorescens biovar B, strain IMV 247, was studied by acid hydrolysis, GLC-MS and 1H and 13C NMR spectroscopy, including 1D and 2D NOE, 2D hybrid TOCSY and ROESY (TORO), and 2D H-detected heteronuclear multiple-bond correlation (HMBC) experiments. The polysaccharide was found to contain L-rhamnose, 3.6-dideoxy-3-[(S)-3-hydroxybutyramido]-D-glucose ...
Zatonskii G V - - 1997
The structure of the acidic O-specific polysaccharide of a Gram-negative bacterium, H. alvei strain PCM 1199, was studied by NMR spectroscopy including two-dimensional correlation spectroscopy (COSY), total correlation spectroscopy (TOCSY), nuclear Overhauser effect spectroscopy (NOESY), 1H, 13C heteronuclear single-quantum coherence (HSQC), 1H, 13C heteronuclear multiple-bond correlation (HMBC), and one-dimensional 1H, ...
Haseley S R - - 1997
A polysaccharide containing D-GlcN, 2-amino-2,6-dideoxy-L-galactose (L-FucN), and 7-acetamido-5-acylamino-3,5,7,9-tetradeoxy-L-glycero-D-galacto-nonulo sonic acid (LegAX), in which the acyl group (X) is either S-3-hydroxybutyryl (50%) or acetyl (50%), was isolated by mild acid hydrolysis treatment, followed by gel-permeation chromatography, of the water-soluble lipopolysaccharide from Acinetobacter baumannii serogroup O24. The polysaccharide, characterised by means of ...
Edashige Y - - 1997
Rhamnogalacturonan I (RG-I) was isolated from the pectin of the cell wall of xylem differentiating zones of sugi (Cryptomeria japonica D. Don, gymnosperm) by digesting with endo-alpha-1,4-polygalacturonase followed by gel-permeation chromatography. Structure of RG-I was characterized by glycosyl composition and glycosyl linkage analyses, partial acid hydrolysis, and lithium (Li)-treatment in ...
Niemetz R - - 1997
The cell wall polymer of Natronococcus occultus (DSM 3396) consists of L-glutamate, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, D-galacturonic acid, D-glucuronic acid and D-glucose in a molar ratio of 5:7:1:8:0.5:0.3. Partial acid hydrolysis of the cell wall polymer produced soluble fragments that could be separated by HPLC. A gamma-glutamyl dipeptide was isolated. In the ...
Draper P - - 1997
Galactosamine was found consistently as a minor component of the envelope of five species of slow-growing mycobacteria, including all the major human pathogens, but not three rapid-growing species. The amino sugar was a component of the arabinogalactan of the cell wall skeleton, and occurred at the level of about one ...
Prauser H - - 1997
A gram-positive, aerobic actinomycete was isolated from soil. Spherical cells of this organism occur singly or form packets, which may cluster. The diagnostic diamino acid of the cell wall peptidoglycan is LL-diaminopimelic acid. The predominate menaquinone is MK-8 (H4), and the main fatty acids are 13-methyl tetradecanoic acid and 12-methyl ...
Gao Q - - 1997
Four acidic heteroglycans, T2a-T2d, were isolated from the body of Tremella fuciformis Berk. They contained 1.9%-2.9% of acetyl groups and were composed of mannose (Man), glucuronic acid (GlcA), and small amounts of xylose (Xyl), glucose (Glc), and fucose (Fuc). According to methylation analysis they had a mannan backbone consisting of ...
Han Y - - 1997
We previously reported that the immunoglobulin M (IgM) monoclonal antibody (MAb) B6.1 protects mice against disseminated candidiasis, whereas the IgM MAb B6 does not. Both MAbs are specific for an adhesin fraction isolated from the cell surface of Candida albicans, but their epitope specificities differ. In the present study, we ...
Hensel A - - 1997
Extracellular polysaccharides (ECP) were isolated in yields of up to 4 mg/ml from the culture media of suspension-cultured cells from Digitalis lanata Ehrh. ECP content was increasing continuously over the first ten days of cultivation and then stayed constant until day 20. ECP were fractionated by ion-exchange chromatography into two ...
Galbraith L - - 1997
A polymeric fraction (the O-antigenic side-chain) has been isolated from the lipopolysaccharide of Burkholderia gladioli pv. gladioli strain NCPPB 1891 after mild acid hydrolysis. The components of the polymer and their molar proportions were L-Rha (1), D-Gal (1), D-Man (1), and O-acetyl (1). By means of chemical degradations and NMR ...
Lehtonen L - - 1997
Presence of muramic acid (as a marker for bacterial cell wall peptidoglycan) was analysed by gas chromatography and mass spectrometry in the peripheral blood leucocytes of subjects from a range of ages (9-80 years) and groups (healthy individuals, patients with rheumatoid arthritis, osteoarthrosis, essential hypertension or multiple sclerosis). Sixty per ...
Reuhs B L - - 1997
An early step in crown gall tumor formation involves the attachment of Agrobacterium tumefaciens to host plant cells. A. tumefaciens C58::A205 (C58 attR) is a Tn3HoHo1 insertion mutant that was found to be avirulent on Bryophyllum daigremontiana and unable to attach to carrot suspension cells. The mutation mapped to an ...
Ahrazem O - - 1997
The structure of acidic fungal polysaccharides, isolated from the cell wall of Cylindrocladium and Calonectria species, has been investigated by chemical analysis, methylation and reductive cleavage analyses, and 1D and 2D 1H and 13C NMR spectroscopy. The polysaccharides have an idealized repeating unit: [formula: see text] linked to a small ...
Knirel Y A - - 1997
The O-specific polysaccharide of Proteus vulgaris O25 was studied by acid hydrolysis and by 1H-NMR and 13C-NMR spectroscopies, including one-dimensional NOE and two-dimensional COSY and heteronuclear 13C,1H correlation (HETCOR) spectroscopy. The polysaccharide was found to contain 3-O-[(R)-1-carboxyethyl]-D-glucose (D-RGlc), and the following structure of the pentasaccharide repeating unit was established: [structure ...
Haseley S R - - 1997
A polysaccharide containing D-Gal, D-GalNAc, 3-(L-2-acetoxypropionamido)-3,6-dideoxy-D-galactose (approximately 80%) and 3-(L-2-hydroxypropionamido)-3,6-dideoxy-D-galactose (approximately 20%) was isolated by mild acid hydrolysis, followed by gel-permeation chromatography, from the phenol-soluble lipopolysaccharide (phenol/water extracted) derived from Acinetobacter strain 94. The polysaccharide, characterised by means of monosaccharide analyses, partial acid hydrolysis, and NMR studies, consisted of a ...
Naumova I B - - 1997
Information on the prevalence, compositions, and structures of anionic carbohydrate-containing polymers of cell walls of Gram-positive bacteria is summarized. The data suggest that these polymers are important for normal functioning of bacterial cells and require further studies. Structural data on teichoic acids found in the literature published over the last ...
Renard C M - - 1997
The hot acid extract of pea hull, HSP, was rich in galacturonic acid, arabinose and xylose. It was fractionated by copper precipitation followed by ion-exchange chromatography. The copper-soluble fraction represented 26% of HSP and was mostly composed of an arabinan with a low degree of branching, some heteroxylans and a ...
Dace R - - 1997
Oat spelts xylan (OSX), fucoidan, kappa carrageenan and chondroitin sulfates A and C were sulfated using chlorosulfonic acid-pyridine complex while the first three were phosphorylated using methane sulfonic acid-phosphorous pentoxide mixture. The compounds were isolated as the sodium salts and their in vitro anticoagulant properties were determined by measuring the ...
Vinogradov E V - - 1997
The structure of the lipopolysaccharide (LPS) from Acinetobacter haemolyticus strain NCTC 10305 (DNA group 4) was elucidated by means of analytical chemistry, NMR spectroscopy and fast-atom-bombardment mass spectrometry. Several oligosaccharides were obtained after deacylation or successive de-O-acylation, dephosphorylation, reduction, and de-N-acylation of LPS. In the major fraction of the LPS, ...
Kajita S. - - 1997
Transgenic tobacco (Nicotiana tabacum L.) plants in which the activity of 4-coumarate:coenzyme A ligase is very low contain a novel lignin in their xylem. Details of changes in hydroxycinnamic acids bound to cell walls and in the structure of the novel lignin were identified by base hydrolysis, alkaline nitrobenzene oxidation, ...
Kumada H - - 1997
Chemical and biological studies were performed on lipopolysaccharide isolated from Selenomonas sputigena ATCC 33150T, a possible causative agent of periodontal diseases. The sugar components of the lipopolysaccharide of S. sputigena were mannose, galactose, glucose, L-glycero-D-mannoheptose (heptose), 2-keto-3-deoxy-octonic acid, glucosamine and galactosamine in a molar ratio of 0.3:1.0:1.0:1.0:0.2:3.0:3.2 (mol/mol heptose). Sephadex ...
Linnerborg M - - 1997
The structure of the O-antigenic polysaccharide from Escherichia coli O167:H5 has been investigated. Sugar and methylation analyses, fast-atom-bombardment mass spectrometry and 1H- and 13C-NMR spectroscopy were the main methods used. The structure of the repeating unit of the polysaccharide was found to be: [formula in text]. Oligosaccharide derivatives of the ...
Zhang J - - 1997
The title oligosaccharides, the tri- through the hexasaccharide in the Inaba series and the penta- and the hexasaccharide in the Ogawa series, have been synthesized using 1-thioglycosides of precursors to 3-O-benzyl-perosamine (4-amino-4,6-dideoxy-D-mannose) as building blocks and N-iodosuccinimide/silver triflate as a promoter. The azido groups in the assembled oligosaccharides were reduced ...
Shin K S - - 1997
A complex pectic polysaccharide (GL-4IIb2) has been isolated from the leaves of Panax ginseng C.A. Meyer, and shown to be a macrophage Fc receptor expression-enhancing polysaccharide. The primary structure of GL-4IIb2 was elucidated by composition. 1H NMR, methylation, and oligosaccharide analyses. GL-4IIb2 consisted of 15 different monosaccharides which included rarely ...
Senchenkova S N - - 1997
The structure of the O-specific polysaccharide chain of Proteus vulgaris OX19 lipopolysaccharide which determines the O1 specificity of Proteus and is used in the Weil-Felix test for diagnostics of rickettsiosis was established. On the basis of 1H- and 13 C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), H-detected 1H, 13C heteronuclear ...
Kocharova N A - - 1997
An acidic O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of the bacterium Providencia alcalifaciens O23 and found to contain D-glucose, D-galactose, 2-acetamido-2-deoxy-D-galactose, and N epsilon-(1-carboxyethyl)-N alpha-(D-glucuronoyl)lysine. On the basis of full and partial acid hydrolyses, selective solvolysis with anhydrous hydrogen fluoride, and 1H- and 13C-NMR spectroscopy, ...
Shashkov A S - - 1997
An acidic O-specific polysaccharide was obtained by mild degradation of the lipopolysaccharide of the bacterium Proteus mirabilis O13 and found to contain D-galactose, 2-acetamido-2-deoxy-D-glucose, and N(epsilon)-(1-carboxyethyl)-N(alpha)-(D-galacturonoyl)lysine. On the basis of full acid hydrolysis and 1H- and 13C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), H-detected heteronuclear 1H, 13C multi-quantum coherence (HMQC), ...
Ikuta K - - 1997
Around 90% of chronic dermatophyte infections are caused by the fungi Trichophyton mentagrophytes and Trichophyton rubrum. One of the causes of the chronic infection resides in the immunosuppressive effects of the cell-wall components of these organisms. Therefore we have attempted to identify the chemical structure of galactomannan, one of the ...
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