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1.
A polysaccharide fraction was isolated form sodium-dodecyl-sulfate (SDS) treated cell walls of Bacillus anthracis (delta Sterne) by hydrofluoric acid (HF) hydrolysis and ethanolic precipitation. The polysaccharide fraction was subsequently purified by several washings with absolute ethanol. Purity of the isolated polysaccharide was tested using the anthrone assay and amino acid analyzer. The molecular mass of the polysaccharide fraction as determined by gel filtration chromatography was about 12000 Da. Preliminary analyses of the polysaccharide was done using thin layer chromatography and amino acid analyzer, and results obtained from these analyses were further confirmed by gas liquid chromatography and 13C-NMR spectroscopy. Results showed that the polysaccharide moiety contained galactose, N-acetylglucosamine, and N-acetylmannosamine in an approximate molar ratio of 3:2:1. This moiety was devoid of muramic acid, alanine, diaminopimelic acid, glutamic acid, and lipid, thus indicating that the isolated polysaccharide was of pure quality.  相似文献   

2.
1. The polysaccharide and mucopeptide components of the cell wall of Lactobacillus fermenti, serological group F, were separated by mild conditions of acid hydrolysis; the polysaccharide was composed of glucose and galactose. 2. Soluble cell-wall products were isolated from cell wall lysed by lysozyme and a Streptomyces enzyme preparation. The lysozyme-dissolved fraction contained a greater proportion of mucopeptide. 3. The soluble preparations were heated in dilute acid to hydrolyse the linkage between the polysaccharide and mucopeptide components and then incubated with acid phosphatase. 4. Inorganic phosphate was released from products of Streptomyces enzyme action but not from products of lysozyme action. 5. The phosphate was shown to be present in the mucopeptide as muramic acid phosphate. It is concluded that in the intact wall polysaccharide is joined to muramic acid by a phosphodiester linkage.  相似文献   

3.
The production of a highly branched beta-1,3-glucan by Aureobasidium pullulans K-1 in Czapek's medium has been found to be stimulated by ascorbic acid. When the culture supernatant, after removal of polysaccharide from the culture filtrate by ethanol precipitation, was concentrated, then added to a new medium and this strain was cultured in the medium, the polysaccharide production was stimulated the same as when L-ascorbic acid was added to the medium. The stimulating substance was partially purified from the supernatant, and was found to be oxalic acid; 0.03% oxalic acid was the most effective concentration for the stimulation of polysaccharide production. The stimulating substance, oxalic acid, was proved to be derived from ascorbic acid added to a medium in an experiment using L-[1-14C]ascorbic acid. We suggest that oxalic acid generated from the metabolism of ascorbic acid in cells of Aureobasidium pullulans K-1 participated in the stimulation of the polysaccharide production by ascorbic acid.  相似文献   

4.
茶叶多糖的糖醛酸含量测定及抗氧化活性研究   总被引:1,自引:0,他引:1  
采用高效液相色谱法对三个产地茶叶多糖的糖醛酸含量进行了测定,该方法具有操作简便、样品无需预处理等特点,稳定性、重现性较好,回收率高,适合于茶叶多糖糖醛酸含量的测定。结果表明不同产地茶叶多糖的糖醛酸含量有明显差异。本文同时研究了不同产地茶叶多糖对超氧自由基和DPPH自由基的清除作用,以评价其抗氧化活性。结果发现不同产地茶叶多糖的抗氧化活性与其糖醛酸含量呈正相关,糖醛酸含量越高,其抗氧化能力越强。  相似文献   

5.
An amino acid was released from the O-specific polysaccharide of Proteus mirabilis O13 by acid hydrolysis and identified as N(epsilon)-[(R)-1-carboxyethyl]-L-lysine by comparison with the authentic sample. An amide of this amino acid with D-galacturonic acid was isolated from the polysaccharide by solvolysis with anhydrous trifluoromethanesulfonic (triflic) acid and characterised by 1H and 13C NMR spectroscopy. These and published data enabled determination of the full structure of the repeating unit of the polysaccharide.  相似文献   

6.
The endotoxin of Bordetella pertussis was cleaved by mild acidic hydrolysis to yield a polysaccharide (polysaccharide I, 15%), a glycolipid (63%) and lipid X (2%). Further treatment of the glycolipid with stronger acid released a second polysaccharide (polysaccharide II, 9%) and material similar to lipid A present in enterobacterial endotoxins. Both polysaccharides possess a single molecule of 3-deoxy-2-octulosonic acid as the reducing, terminal sugar. In polysaccharide II the octulosonic acid is phosphorylated in position 5 and presumably substituted in position 4; in polysaccharide I the octulosonic acid is not phosphorylated, but is substituted in position 5. Following treatment of the endotoxin with strong base, a fragment was isolated that contained bound, non-phosphorylated 3-deoxy-2-octulosonic acid, glucosamine phosphate and fatty acids. This indicated that polysaccharide I, like polysaccharide II, was bound to the lipid region of the endotoxin. The endotoxin structure thus defined is different from that proposed for the lipopolysaccharides of enterobacteria.  相似文献   

7.
Studies of the lipopolysaccharide of Pseudomonas alcaligenes strain BR 1/2 were extended to the polysaccharide moiety. The crude polysaccharide, obtained by mild acid hydrolysis of the lipopolysaccharide, was fractionated by gel filtration. The major fraction was the phosphorylated polysaccharide, for which the approximate proportions of residues were; glucose (2), rhamnose (0.7), heptose (2-3), galactosamine (1), alanine (1), 3-deoxy-2-octulonic acid (1), phosphorus (5-6). The heptose was l-glycero-d-manno-heptose. The minor fractions from gel filtration contained free 3-deoxy-2-octulonic acid, P(i) and PP(i). The purified polysaccharide was studied by periodate oxidation, methylation analysis, partial hydrolysis, and dephosphorylation. All the rhamnose and part of the glucose and heptose occur as non-reducing terminal residues. Other glucose residues are 3-substituted, and most heptose residues are esterified with condensed phosphate residues, possibly in the C-4 position. Free heptose and a heptosylglucose were isolated from a partial hydrolysate of the polysaccharide. The location of galactosamine in the polysaccharide was not established, but either the C-3 or C-4 position appears to be substituted and a linkage to alanine was indicated. In its composition, the polysaccharide from Ps. alcaligenes resembles core polysaccharides from other pseudomonads: no possible side-chain polysaccharide was detected.  相似文献   

8.
S Lim  M R Salton 《Microbios》1985,44(178):95-105
A polysaccharide consisting of rhamnose, galactose, glucosamine and ester-linked succinic acid was extracted from the isolated cell walls of Micrococcus agilis by the hot water-phenol and 5% trichloroacetic acid (TCA) extraction methods. The hot water-phenol extractable polysaccharide accounted for 30% of the weight of the wall, with 23% by the TCA method. Phosphorus contents were less than 0.01% of the polysaccharide. Succinyl residues released by alkali treatment (0.1 N NaOH, 30 min, 37 degrees C) were identified by gas-liquid chromatography, and accounted for 6.3% and 5.1% of the polysaccharide purified from the hot water-phenol and TCA extracts, respectively. The polysaccharide was not bound when chromatography on Concanavalin A-Sepharose 4B (Con A/Sepharose 4B) columns was performed and it could thus be separated from any residual membrane lipomannan. The purified polysaccharide behaved as a negatively-charged polymer on electrophoresis in 1% agarose (at pH 8.6). A strong cross-reaction, unaffected by removal of the succinyl groups, was observed with type XXIII pneumococcal polysaccharide antiserum indicating the presence of L-rhamnose, linked through non-reducing, lateral end groups.  相似文献   

9.
The structure of an acidic polysaccharide from Pseudoalteromonas atlantica strain 14165 containing 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno-non-2-ulosonic acid (di-N-acetylpseudaminic acid, Pse5Ac7Ac) has been elucidated. The polysaccharide was studied by 1H and 13C NMR spectroscopy, including 2D experiments, along with sugar and methylation analyses. After a selective hydrolysis a modified polysaccharide devoid of its side chain could be isolated. It was found that the polysaccharide has pentasaccharide repeating units with following structure: [structure: see text].  相似文献   

10.
Coaggregation between Streptococcus sanguis H1 and Capnocytophaga ochracea ATCC 33596 cells is mediated by a carbohydrate receptor on the former and an adhesin on the latter. Two methods were used to release the carbohydrate receptor from the gram-positive streptococcus, autoclaving and mutanolysin treatment. The polysaccharide released from the streptococcal cell wall by either treatment was purified by ion-exchange chromatography; this polysaccharide inhibited coaggregation when preincubated with the gram-negative capnocytophaga partner. After hydrolysis of the polysaccharide by hydrofluoric acid (HF), the major oligosaccharide of the polysaccharide was purified by high-performance liquid chromatography. By analysis of the HF hydrolysis of the polysaccharide and the purified oligosaccharide, this major oligosaccharide appeared to be the repeating unit of the polysaccharide, with minor components resulting from internal hydrolysis of the major oligosaccharide. Gas chromatography results showed that the oligomer was a hexasaccharide, consisting of rhamnose, galactose, and glucose, in the ratio of 2:3:1, respectively. By weight, the purified hexasaccharide was a fourfold-more-potent inhibitor of coaggregation than the native polysaccharide. Resistance to hydrolysis by sulfuric acid alone and susceptibility to hydrolysis by HF suggested that oligosaccharide chains of the polysaccharide are linked by phosphodiester bonds. Studies with a coaggregation-defective mutant of S. sanguis H1 revealed that the cell walls of the mutant contained neither the polysaccharide nor the hexasaccharide repeating unit. The purification of both a polysaccharide and its constituent hexasaccharide repeating unit, which both inhibited coaggregation, and the absence of this polysaccharide or hexasaccharide on a coaggregation-defective mutant strongly suggest that the hexasaccharide derived from the polysaccharide functions as the receptor for the adhesin from C. ochracea ATCC 33596.  相似文献   

11.
Blood group H-active polysaccharide has been prepared from "smooth" strain Escherichia coli 2B-V by Freeman's method, alpha-Fucosidase derived from Bacillus fluminans caused the liberation of fucose from this polysaccharide, together with concomitant loss of blood group H activity. The results of quantitative microanalysis, borohydride reduction, the Morgan-Elson reaction and enzymic hydrolysis with betagalactosidase using isolated oligosaccharides obtained by partial acid hydrolysis indicated that the O-specific side chain of the polysaccharide has a pentassaccharide unit which is beta-D-Gal-(1 leads to 3)-D-GalNAc-(1 leads to 3)-D-GalNAc-Fuc with a D-glucose residue bound at some undetermined point on this structure. It was considered that terminal non-reducing fucose of the polysaccharide was liberated by partial acid hydrolysis.  相似文献   

12.
The polysaccharide-peptidoglycan complex, which was prepared with lysozyme from Streptomyces roseochromogenes IAM53 cell walls, was hydrolyzed with lytic enzyme of Flavo-bacterium to separate polysaccharide. The enzymatically prepared polysaccharide (100 mg) contained 500 μmoles of hexoses, 40 μmoles of hexosamines and 31 μmoles of phosphate. Hexoses consisted of mannose and galactose in a molar ratio of 5 to 1. Hexosamines consisted of equimolar glucosamine and muramic acid, a half of which was identified as muramic acid 6-phosphate. The reducing end of the polysaccharide was muramic acid. The polysaccharide extracted with trichloroacetic acid contained no muramic acid-phosphate. So the polysaccharide moiety of S. roseochromogenes cell walls must be linked covalently to 6-position of muramic acid in peptidoglycan through phosphate,  相似文献   

13.
Glycosaminoglycans were extracted from bovine liver capsule with 4 M-guanidinium chloride, resulting in solubilization of approx. 90% of the total uronic acid-containing polysaccharide of the tissue. The extracted polysaccharide was purified and fractionated by anion-exchange chromatography on DEAE-cellulose, density-gradient ultracentrifugation in CsCl and finally gel chromatography on Sepharose 4B. By using these procedures, the two major polysaccharide components, dermatan sulphate and heparin, which constituted 55 and 30% respectively of the total glycosaminoglycan content of the tissue, were separated from each other. Analysis of the macromolecular properties of the two polysaccharides showed that heparin existed exclusively as single polysaccharide chains, whereas dermatan sulphate occurred largely as a proteoglycan (protein content, 74% dry wt.). The purified heparin preparation was subjected to sedimentation-equilibrium ultracentrifugation, indicating a molecular weight of 8800. Analysis for neutral sugars (by g.l.c.) showed 0.1 residue of xylose and 0.2 residue of galactose/polysaccharide chain; serine amounted to 0.3 residue/polysaccharide chain. Reduction of the heparin with NaB3H4 resulted in incorporation of 3H, approximately corresponding to one reducible group/polysaccharide chain. The 3H-labelled sugar residue was liberated by a combination of acid hydrolysis and deaminative cleavage of the polysaccharide with HNO2; it was subsequently identified as an aldonic acid by paper electrophoresis. Most of the heparin chains thus contained a uronic acid residue in reducing position. It is suggested that heparin isolated from bovine liver capsule is a degradation product released from larger molecules by an endo-glycuronidase.  相似文献   

14.
When 120 mg glucose/ml was used as a carbon source, in shake culture Aspergillus niger Yang no. 2 maximally produced only 15.4 mg citric acid/ml but accumulated 3.0 mg extracellular polysaccharide/ml. The polysaccharide secreted by mycelia of Yang no. 2 in shake culture was confirmed to be an amylose-like alpha-1,4-glucan by hydrolysis analysis with acid, amylase and glucoamylase. However, in static cultures, such as semisolid and surface cultures free from physical stresses caused by shaking damage, Yang no. 2 produced more citric acid but did not accumulate the polysaccharide. With cultivation time in shake culture, the amount of extracellular polysaccharide and the viscosity of the culture broth increased. The increase of shaking speed caused a remarkable increase in the accumulation of extracellular polysaccharide, e.g. 11.2 mg extracellular polysaccharide/ml was accumulated in the medium at a shaking speed of 200 rpm. The addition of 2.0 mg carboxymethylcellulose (CMC)/ml as a viscous additive to the medium reduced drastically the amount of extracellular polysaccharide accumulated to 1.5 mg/ml, but increased the citric acid produced to 52.0 mg/ml. However, intracellular polysaccharide accumulation kept up a steady rate of 0.26 microgram/mg dried mycelium through the entire period of cultivation. The addition of 3.0 mg polysaccharide/ml purified from the culture broth to the medium at the start of a culture resulted in a decrease of extracellular polysaccharide accumulation but an increase of citric acid accumulation. From electronmicroscopic observation, cell surfaces of hyphae cultivated with CMC were smooth, while hyphae cultivated without CMC had fibrous and granular polysaccharide on the cell surface. These results suggested that Yang no. 2 secreted the polysaccharide on the cell surface as a viscous substance and/or a shock absorber to protect itself from physical stresses caused by shaking damage in shake culture.  相似文献   

15.
Polysaccharide material was found in the proteolysis glycopolypeptide fraction from normal human gastric mucus. The polysaccharide was identified by carbohydrate and amino acid analyses, by elemental analysis and from its behaviour on density-gradient ultracentrifugation. The polysaccharide is polydisperse with a weight-average molecular mass of 300 000 Da. Over 85% of the polysaccharide consists of galactose, and this represents 26% of all the galactose present in the fractions after beta-elimination with reduction of the glycopolypeptide material.  相似文献   

16.
A polysaccharide-fatty acid complex was isolated from the cell surface of Candida tropicalis growing on alkanes. This complex was solubilized by Pronase treatment of whole cells. A decrease in alkane-binding affinity was observed after Pronase treatment, resulting in 10 to 12% of the yeast dry cell weight being released as polysaccharide. The isolated polysaccharide contained 2.5% fatty acids. C. tropicalis and Saccharomyces cerevisiae grown with glucose contained only traces of fatty acids in the corresponding polysaccharide fraction. The fatty acids were not removed from the polysaccharide moiety by gel filtration. Extraction of the polysaccharide with chloroform-methanol showed that fatty acids were covalently bound to the polysaccharide. The amphipathic nature of the isolated polysaccharide and the hydrocarbon-induced formation suggest a possible role in alkane metabolism.  相似文献   

17.
Serological Activity of Staphylococcal Polysaccharide   总被引:2,自引:1,他引:1       下载免费PDF全文
The polysaccharide from cell walls of coagulase-positive staphylococci coated both latex particles and tanned red cells for agglutination by human sera and by specific staphylococcal antisera. Treatment with trypsin or autoclaving destroyed the capacity of polysaccharide to coat particles but did not affect precipitation of antibody. Periodic acid destroyed both properties. The teichoic acid portion of the staphylococcal polysaccharide displayed precipitin activity similar to polysaccharide, but it did not coat either latex particles or tanned red cells. Teichoic acid did, however, inhibit specific agglutination of polysaccharide-coated particles or cells.  相似文献   

18.
Several strains of bacteriophage have been isolated that induce the formation of a polysaccharide hydrolase after infection of Klebsiella aerogenes type 54 [A3(S1)]. The action of this enzyme on polysaccharide solutions was to decrease their viscosity and increase their reducing value. These effects were associated with the release of two oligosaccharides (O1 and O2) from the polysaccharide. These two substances are not identical with any of the four oligosaccharides isolated from autohydrolysates. The two enzymically isolated fractions have been tentatively identified as tetrasaccharides, and oligosaccharide O2 is probably an acetylated version of oligosaccharide O1. This latter oligosaccharide differs in some way, still unknown, from the tetrasaccharide cellobiosylglucuronosylfucose found in acid hydrolysates of the slime polysaccharide. The enzyme is limited in its activity to the polysaccharide excreted by the A3 strain of K. aerogenes type 54 or by similar strains. It is also active on the polysaccharides altered by acid or alkaline treatment. The enzyme has optimum activity at pH6.5. A study of the products released by enzyme action has shown it to be a fucosidase splitting the fucosylglucose linkages found in the intact polysaccharide.  相似文献   

19.
The capsular polysaccharide from Klebsiella Serotype K40 contains D-galactose, D-mannose, L-rhamnose, and D-glucuronic acid in the ratios of 4:1:1:1. Methylation analysis of the native and carboxyl-reduced polysaccharide provided information about the glycosidic linkages in the repeating unit. Degradation of the permethylated polymer with base established the identity of the sugar unit preceding the glycosyluronic acid residue. The modes of linkages of different sugar residues were further confirmed by Smith degradation and partial hydrolysis of the K40 polysaccharide. The anomeric configurations of the different sugar residues were determined by oxidation of the peracetylated native and carboxyl-reduced polysaccharide with chromium trioxide. Based on all of these results, the heptasaccharide structure 1 was assigned to the repeating unit of the K40 polysaccharide. (Formula: see text)  相似文献   

20.
Structural studies of the capsular polysaccharide of Klebsiella type 52   总被引:1,自引:0,他引:1  
The structure of the capsular polysaccharide from Klebsiella Type 52 has been investigated. Methylation analysis, characterization by gas-liquid chromatography-mass spectrometry of oligosaccharide derivatives obtained on partial hydrolysis of the methylated polysaccharide with acid, and specific degradation of the methylated polysaccharide by successive treatments with base and acid followed by characterization of the product, were the principal methods used. The polysaccharide is composed of hexasaccharide repeating-units containing D-glucuronic acid, D-galactose, and L-rhamnose, in the ratios 1:3:2. A structure for these units, disregarding the anomeric natures of the sugar residues, is proposed.  相似文献   

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