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1.
Structural studies were carried out on lipoteichoic acids obtained from defatted cells of 10 Bacillus strains by phenol-water partition followed by chromatography on DEAE-Sephacel and Octyl-Sepharose columns. A group of the tested bacteria (group A), Bacillus subtilis, Bacillus licheniformis, and Bacillus pumilus, was shown to have a diacyl form of lipoteichoic acids which contained D-alanine, D-glucose, D-glucosamine, fatty acids, and glycerol in molar ratios to phosphorus of 0.35 to 0.69, 0.07 to 0.15 to 0.43, 0.06 to 0.11, and 0.95 to 1.18, respectively, whereas the other group (group B), Bacillus coagulans and Bacillus megaterium, had diacyl lipoteichoic acids which contained D-galactose, fatty acids, and glycerol in molar ratios to phosphorus of 0.05 to 0.42, 0.06 to 0.12, and 0.96 to 1.07, respectively. After treatment with 47% hydrogen fluoride, the lipoteichoic acids obtained from group A strains commonly gave a hydrophobic fragment, gentiobiosyl-beta (1----1 or 3)diacylglycerol, in addition to dephosphorylated repeating units, glycerol, 2-D-alanylglycerol, N-acetyl-D-glucosaminyl-alpha (1----2)glycerol, and D-alanyl-N-acetyl-D-glucosaminyl-alpha (1----2)glycerol, whereas the lipoteichoic acids from group B strains yielded diacylglycerol in addition to glycerol and D-galactosyl-alpha (1----2)glycerol. The results together with data from Smith degradations indicate that in the lipoteichoic acids of group A strains the polymer chains, made up of partially alanylated glycerol phosphate and glycosylglycerol phosphate units, are joined to the acylglycerol anchors through gentiobiose. However, in the lipoteichoic acids of group B strains, the partially galactosylated poly(glycerolphosphate) chains are believed to be directly linked to the acylglycerol anchors.  相似文献   

2.
N Kojima  Y Araki    E Ito 《Journal of bacteriology》1985,161(1):299-306
The structure of the linkage regions between ribitol teichoic acids and peptidoglycan in the cell walls of Staphylococcus aureus H and 209P and Bacillus subtilis W23 and AHU 1390 was studied. Teichoic acid-linked saccharide preparations obtained from the cell walls by heating at pH 2.5 contained mannosamine and glycerol in small amounts. On mild alkali treatment, each teichoic acid-linked saccharide preparation was split into a disaccharide identified as N-acetylmannosaminyl beta(1----4)N-acetylglucosamine and the ribitol teichoic acid moiety that contained glycerol residues. The Smith degradation of reduced samples of the teichoic acid-linked saccharide preparations from S. aureus and B. subtilis gave fragments characterized as 1,2-ethylenediol phosphate-(glycerolphosphate)3-N-acetylmannosaminyl beta(1----4)N- -acetylxylosaminitol and 1,2-ethylenediolphosphate-(glycerol phosphate)2-N-acetylmannosaminyl beta(1----4)N-acetylxylosaminitol, respectively. The binding of the disaccharide unit to peptidoglycan was confirmed by the analysis of linkage-unit-bound glycopeptides obtained from NaIO4 oxidation of teichoic acid-glycopeptide complexes. Mild alkali treatment of the linkage-unit-bound glycopeptides yielded disaccharide-linked glycopeptides, which gave the disaccharide and phosphorylated glycopeptides on mild acid treatment. Thus, it is concluded that the ribitol teichoic acid chains in the cell walls of the strains of S. aureus and B. subtilis are linked to peptidoglycan through linkage units, (glycerol phosphate)3-N-acetylmannosaminyl beta(1----4)N-acetylglucosamine and (glycerol phosphate)2-N-acetylmannosaminyl beta(1----4)N-acetylglucosamine, respectively.  相似文献   

3.
An anti-complementary arabinogalactan (AGIIb-1), isolated from the roots of Angelica acutiloba Kitagawa, has been subjected to methylation analysis, digestion with alpha-L-arabinofuranosidase, controlled Smith-degradation, and partial acid hydrolysis. AGIIb-1 consisted of arabinose, galactose, rhamnose, galacturonic acid, and glucuronic acid in the molar ratios 1.8-2.2:1.0:0.2-0.3:0.2-0.4:0.1. AGIIb-1 contained mainly an arabino-3,6-galactan moiety, and most of the Ara was present as alpha-L-arabinofuranosyl residues in the non-reducing terminals and the highly polymerised and branched side-chains which were attached mainly to positions 3 and 6 of (1----6)- and (1----3)-linked Gal, respectively. Some Ara-containing chains were also attached to (1----4)-linked Gal residues. The 13C-n.m.r. data for AGIIb-1 showed that the Galp was beta. Mild acid hydrolysis of AGIIb-1 yielded several linear and highly branched arabino-oligosaccharides, a neutral arabinogalactan, and two acidic arabinogalactans. Some arabino-oligosaccharides contained a (1----4)-linked Arap at the reducing terminal. The neutral arabinogalactan contained (1----3)-, (1----4)-, and (1----6)-linked and 3,6-di-O-substituted Gal, whereas the acidic arabinogalactans contained, in addition, non-reducing terminal GlcA, (1----4)-linked GalA, and 2,4-di-O-substituted Rha. The anti-complementary activity was decreased when AGIIb-1 was partially hydrolysed with mild acid (10mM HCl, 100 degrees, 10 min), but treatment with exo-alpha-L-arabinofuranosidase markedly enhanced the activity.  相似文献   

4.
Teichoic acid-glycopeptide complexes were isolated from lysozyme digests of the cell walls of Bacillus coagulans AHU 1631, AHU 1634, and AHU 1638, and the structure of the teichoic acid moieties and their linkage regions was studied. On treatment with hydrogen fluoride, each of the complexes gave a hexosamine-containing disaccharide, which was identified to be glucosyl(beta 1----4)N-acetylglucosamine, in addition to dephosphorylated repeating units of the teichoic acids, namely, galactosyl(alpha 1----2)glycerol and either galactosyl(alpha 1----2)[glucosyl(alpha 1----1/3)]glycerol (AHU 1638) or galactosyl(alpha 1----2)[glucosyl(beta 1----1/3)]glycerol (AHU 1631 and AHU 1634). From the results of Smith degradation, methylation analysis, and partial acid hydrolysis, the teichoic acids from these strains seem to have the same backbone chains composed of galactosyl(alpha 1----2)glycerol phosphate units joined by phosphodiester bonds at C-6 of the galactose residues. The presence of the disaccharide, glucosyl(beta 1----4)N-acetylglucosamine, in the linkage regions between teichoic acids and peptidoglycan was confirmed by the isolation of a disaccharide-linked glycopeptide fragment from each complex after treatment with mild alkali and of a teichoic acid-linked saccharide from each cell wall preparation after treatment with mild acid. Thus, it is concluded that despite structural differences in the glycosidic branches, the teichoic acids in the cell walls of the three strains are linked to peptidoglycan through a common linkage saccharide, glucosyl (beta 1----4) N-acetylglucosamine.  相似文献   

5.
The lipoteichoic acids were isolated from phenol extracts of four Listeria strains representing serotypes 4a, 4b, 6a, and 6 to compare the differences in structure of amphiphilic polysaccharides from various serotypes of Listeria spp. The lipoteichoic acids from the four strains examined had the same structure in both hydrophilic chains and lipid portions. On the basis of the results of nuclear magnetic resonance spectroscopy and Smith degradation, the hydrophilic chains were shown to be 1,3-linked poly(glycerol phosphate) in which some of the glycerol residues had alpha-galactosyl substituents. The lipid portions were released by treatment with 46% hydrogen fluoride or 98% acetic acid. They were determined to be 3(1)-(2'-O-alpha-D-galactopyranosyl-alpha-D-glucopyranosyl)-1(3), 2-diacylglycerol and 3(1)-[6'-phosphatidyl-2'-O-(alpha-D-galactopyranosyl)-alpha- D-glucopyranosyl]-1(3),2-diacylglycerol. The degrees of glycosyl substitution and proportions of the two lipids varied to some extent among these four strains.  相似文献   

6.
S Kaya  K Yokoyama  Y Araki    E Ito 《Journal of bacteriology》1984,158(3):990-996
The structure of teichoic acid-glycopeptide complexes isolated from lysozyme digests of cell walls of Bacillus subtilis (four strains) and Bacillus licheniformis (one strain) was studied to obtain information on the structural relationship between glycerol teichoic acids and their linkage saccharides. Each preparation of the complexes contained equimolar amounts of muramic acid 6-phosphate and mannosamine in addition to glycopeptide components and glycerol teichoic acid components characteristic of the strain. Upon treatment with 47% hydrogen fluoride, these preparations gave, in common, a hexosamine-containing disaccharide, which was identified as N- acetylmannosaminyl (1----4) N-acetylglucosamine, along with large amounts of glycosylglycerols presumed to be the dephosphorylated repeating units of teichoic acid chains. The glycosylglycerol obtained from each bacterial strain was identified as follows: B. subtilis AHU 1392, glucosyl alpha (1----2)glycerol; B. subtilis AHU 1235, glucosyl beta(1----2) glycerol; B. subtilis AHU 1035 and AHU 1037, glucosyl alpha (1----6)galactosyl alpha (1----1 or 3)glycerol; B. licheniformis AHU 1371, galactosyl alpha (1----2)glycerol. By means of Smith degradation, the galactose residues in the teichoic acid-glycopeptide complexes from B. subtilis AHU 1035 and AHU 1037 and B. licheniformis AHU 1371 were shown to be involved in the backbone chains of the teichoic acid moieties. Thus, the glycerol teichoic acids in the cell walls of five bacterial strains seem to be joined to peptidoglycan through a common linkage disaccharide, N- acetylmannosaminyl (1----4)N-acetylglucosamine, irrespective of the structural diversity in the glycosidic branches and backbone chains.  相似文献   

7.
A ribitol-containing lipoteichoic acid was obtained from the 20,000 x g supernatant fraction of Staphylococcus aureus H by extraction with Triton X-100 followed by fractionation on Sepharose 6B and DEAE-cellulose columns. The purified lipoteichoic acid was composed of phosphate, glycerol, glucose, glucosamine, ribitol, and fatty acids in a molar ratio of 1 : 0.9 : 0.06 : 0.03 : 0.09 : 0.07. Based on the structural analysis of fragments from alkali and HF hydrolysis, the lipoteichoic acid appears to consist of three moieties, namely a ribitol phosphate oligomer, poly(glycerol phosphate) which has about 30 glycerol phosphate units, and beta-glucosyl-beta-glucosyl(1 leads to 1)diacylglycerol. N-Acetylglucosamine was linked to the ribitol residues. The lipoteichoic acid serves as an acceptor of glycosyl moieties from UDP-glucose and UDP-N-acetylglucosamine in the enzyme reaction catalyzed by the membrane preparation. The rate of enzymatic glycosylation was increased by prior treatment of the lipoteichoic acid with N-acetyl-beta-D-glucosaminidase. The glycosylation seems to occur at the ribitol residues of the lipoteichoic acid.  相似文献   

8.
The occurrence, structure, and glycosylation of lipoteichoic acids were studied in 15 Bacillus strains, including Bacillus cereus (4 strains), Bacillus subtilis (5 strains), Bacillus licheniformis (1 strain), Bacillus polymyxa (2 strains), and Bacillus circulans (3 strains). Whereas in the cells of B. polymyxa and B. circulans neither lipoteichoic acid nor related amphipathic polymer could be detected, the cells of other Bacillus strains were shown to contain lipoteichoic acids built up of poly(glycerol phosphate) backbone chains and hydrophobic anchors [gentiobiosyl(beta 1----1/3)diacylglycerol or monoacylglycerol]. The lipoteichoic acid chains of the B. licheniformis strain and three of the B. subtilis strains had N-acetylglucosamine side branches, but those of the B. cereus strains and the remaining two B. subtilis strains did not. The membranes of the B. licheniformis strain and the first three B. subtilis strains exhibited enzyme activities for the synthesis of beta-N-acetylglucosamine-P-polyprenol and for the transfer of N-acetylglucosamine from this glycolipid to endogenous acceptors presumed to be lipoteichoic acid precursors. In contrast, the membranes of the other strains lacked both or either of these two enzyme activities. The correlation between the occurrence of N-acetylglucosamine-linked lipoteichoic acids and the distribution of these enzymes is consistent with the previously proposed function of beta-N-acetylglucosamine-P-polyprenol as a glycosyl donor in the introduction of alpha-N-acetylglucosamine branches to lipoteichoic acid backbone chains.  相似文献   

9.
The sugar chains of interphotoreceptor retinol-binding protein purified from the interphotoreceptor matrix of bovine eyes were liberated from the polypeptide portion by hydrazinolysis followed by N-acetylation and NaB[3H]4 reduction. The oligosaccharide fraction thus obtained was separated into four acidic fractions by paper electrophoresis. The four acidic fractions were confirmed to be mixtures of mono-, di-, tri-, and tetrasialyloligosaccharides. Both N-acetyl- and N-glycolylneuraminic acids were found as sialic acids of interphotoreceptor retinol-binding protein. The monosialylated oligosaccharide fraction, which accounted for 40 molar per cent of the total oligosaccharides liberated, was a mixture of the following hybrid-type oligosaccharides: (Formula: see text) This is the first time that fucosylated hybrid-type oligosaccharides have been found in any glycoprotein. The di-, tri-, and tetrasialyloligosaccharide fractions were composed of biantennary complex-type oligosaccharides, the outer chains of which are either Sia alpha 2----(3- or 6-linked)Gal beta 1----3(Sia alpha 2----6)GlcNac or Sia alpha 2----(3- or 6-linked)Gal beta 1----4GlcNAc.  相似文献   

10.
Acid-soluble and alkali-insoluble glucan fractions were prepared from yeast, hyphal and germ-tube forming cells of Candida albicans. Alkali-insoluble glucan was also extracted from purified yeast cell walls. Paper chromatography of partial acid hydrolysates confirmed that the glucan preparations contained beta(1----3)- and beta(1----6)-chains but no mixed intra-chain beta(1----3)/(1----6) linkages. Methylation and 13C-NMR analyses showed that the acid-soluble glucan consisted of a highly branched polymer composed mainly (67.0% to 76.6%) of beta(1----6)-linked glucose residues. The alkali-insoluble glucan from yeast and hyphal cells contained from 29.6% to 38.9% beta(1----3) and 43.3% to 53.2% beta(1----6) linkages. Alkali-insoluble glucan from germ-tube forming cells consisted of 67.0% beta(1----3) and 14% beta(1----6) linkages. Branch points accounted for 6.7%, 12.3% and 17.4% of the residues in the alkali-insoluble glucan of yeast, germ-tube forming and hyphal cells, respectively.  相似文献   

11.
The minor teichoic acid linked to glycopeptide was isolated from lysozyme digests of Bacillus coagulans AHU 1631 cell walls, and the structure of the teichoic acid moiety and its junction with the peptidoglycan were studied. Hydrolysis of the teichoic-acid--glycopeptide complex with hydrogen fluoride gave a nonreducing oligosaccharide composed of glucose, galactose and glycerol in a molar ratio of 3:1:1 which was presumed to be dephosphorylated repeating units of the polymer chain. From the results of structural analysis involving NaIO4 oxidation, methylation and acetolysis, the above fragment was characterized as glucosyl(beta 1----3)glucosyl(beta 1----6)galactosyl(beta 1----6)glucosyl(alpha 1----1/3)glycerol. In addition, the Smith degradation of the complex yielded a phosphorus-containing fragment identified as glycerol-P-6-glucosyl(beta 1----1/3)glycerol. These results led to the most likely structure for the repeating units of the teichoic acid, -6[glucosyl(beta 1----3)]glucosyl(beta 1----6)galactosyl(beta 1----6)glucosyl(alpha 1----1/3)glycerol-P-. The minor teichoic acid, just like the major teichoic acid bound to the linkage unit, was released by heating the cell walls at pH 2.5. The mild alkaline hydrolysis of the minor teichoic acid after reduction with NaB3H4 gave labeled saccharides characterized as glucosyl(beta 1----6)galactitol and glucosyl(beta 1----3)glucosyl(beta 1----6)galactitol, together with a large amount of the unlabeled repeating units of the teichoic acid chain. Thus, the minor teichoic acid chain is believed to be directly linked to peptidoglycan at the galactose residue of the terminal repeating unit without a special linkage sugar unit.  相似文献   

12.
Regenerating spheroplasts of Candida albicans formed organized glucan nets in liquid culture. The nets consisted of interwoven microfibrils about 50 nm wide, but of an undetermined length. Partial acid hydrolysis of the polysaccharide showed the presence of chains of beta(1----3)- and beta(1----6)-linked glucose residues, but no intrachain beta(1----3) and beta(1----6) linkages. Periodate oxidation and GLC of the methylated glucan indicated a highly branched polymer (9.5% branch points). Sequential enzymic degradation of the isolated nets confirmed the presence of chains of beta(1----3)- and beta(1----6)-linked glucose residues. Degradation by (1----3)-beta- and (1----6)-beta-glucanase released 23% (w/w) and 30% (w/w) respectively of the carbohydrate as glucose equivalents. The residual material was degraded by chitinase. Equal amounts of N-acetylglucosamine and glucose equivalents were detected in the chitinase hydrolysate, suggesting a possible linkage between glucan and chitin. Our data indicate that the cell wall of C. albicans contains at least two highly branched glucans with predominantly beta(1----3) or beta(1----6) linkages.  相似文献   

13.
Pneumococcal lipoteichoic acid was extracted and purified by a novel, quick and effective procedure. Structural analysis included methylation, periodate oxidation, Smith degradation, oxidation with CrO3, and fast-atom-bombardment mass spectrometry. Hydrolysis with 48% (by mass) HF and subsequent phase partition yielded the lipid anchor (I), the dephosphorylated repeating unit of the chain (II) and a cleavage product of the latter (III). The proposed structures are: (I) Glc(beta 1----3)AATGal(beta 1----3)Glc(alpha 1----3)acyl2Gro, (II) Glc(beta 1----3)AATGal(alpha 1----4)GalNAc(alpha 1----3)GalNAc(beta 1----1)ribitol and (III) Glc(beta 1----3)AATGal(alpha 1----4)GalNAc(alpha 1----3)GalNAc, where AATGal is 2-acetamido-4-amino-2,4,6-trideoxygalactose, and all sugars are in the pyranose form and belong to the D-series. Alkaline phosphodiester cleavage of lipoteichoic acid, followed by treatment with phosphomonoesterase, resulted in the formation of II and IV, with IV as the prevailing species: [sequence: see text] The linkage between the repeating units was established as phosphodiester bond between ribitol 5-phosphate and position 6 of the glucosyl residue of adjacent units. The chain was shown to be linked to the lipid anchor by a phosphodiester between its ribitol 5-phosphate terminus and position 6 of the non-reducing glucosyl terminus of I. The lipoteichoic acid is polydisperse: the chain length may vary between 2 and 8 repeating units and variations were also observed for the fatty acid composition of the diacylglycerol moiety. Preliminary results suggest that repeating units II and IV are enriched in separate molecular species. All species were associated with Forssman antigenicity, albeit to a various extent when related to the non-phosphocholine phosphorus. Owing to its unique structure, the described macroamphiphile may be classified as atypical lipoteichoic acid.  相似文献   

14.
The structure of the linkage unit between ribitol teichoic acid and peptidoglycan in the cell walls of Listeria monocytogenes EGD was studied. A teichoic-acid--glycopeptide preparation isolated from lysozyme digests of the cell walls of this strain contained mannosamine, glycerol, glucose and muramic acid 6-phosphate in an approximate molar ratio of 1:1:2:1, together with large amounts of glucosamine and other components of teichoic acid and glycopeptides. A teichoic-acid-linked sugar preparation, obtained by heating the cell walls at pH 2.5, also contained glucosamine, mannosamine, glycerol and glucose in an approximate molar ratio of 25:1:1:2. Part of the glucosamine residues were shown to be involved in the linkage unit. Thus, on mild alkaline hydrolysis, the teichoic-acid-linked sugar preparation gave a disaccharide characterized as N-acetylmannosaminyl(beta 1----4)-N-acetylglucosamine [ManNAc(beta 1----4)GlcNAc] in addition to the ribitol teichoic acid moiety, whereas the teichoic-acid - glycopeptide was separated into disaccharide-linked glycopeptide and the ribitol teichoic acid moiety by the same procedure. Furthermore, Smith degradation of the cell walls gave a characteristic fragment, EtO2-P-Glc(beta 1----3)Glc(beta 1----1/3)Gro-P-ManNAc(beta 1----4)GlcNAc (where EtO2 = 1,2-ethylenediol and Gro = glycerol). The results lead to the conclusion that in the cell walls of this organism, the ribitol teichoic acid chain is linked to peptidoglycan through a novel linkage unit, Glc(beta 1----3)Glc(beta 1----1/3)Gro-P-(3/4)ManNAc-(beta 1----4)GlcNAc.  相似文献   

15.
A cell-wall preparation from the cells of Elsinoe leucospila, which produces elsinan extracellularly when grown on sucrose or glucose-potato extract medium, was fractionated systematically. The heteropolysaccharide that was released by treatment with Actinase E digestion, comprised D-mannose, D-galactose, and D-glucose (molar ratio, 1.5:1.0:0.1). Methylation, mild acid hydrolysis, and 13C-NMR studies suggested that the polysaccharide contains a backbone of alpha-(1----6)-linked D-mannose residues having two kinds of side chains, one attached at the O-4 with single or short beta-(1----6)-linked D-galactofuranosyl residues, and the other attached at O-2 with short side chains, most probably, of alpha-(1----3)-linked D-mannopyranosyl residues. A moderately branched D-glucan fraction, obtained from the cold alkali extract, was fractionated to give an antitumor-active purified beta-(1----3)-glucan having branches of single beta-D-glucosyl groups, one out of eight D-glucose residues being substituted at the O-6.  相似文献   

16.
This study shows for the first time microheterogeneity of 1,3-linked poly(glycerophosphate) lipoteichoic acids. The lipoteichoic acids investigated were those of Enterococcus faecalis Kiel 27738 (I), Enterococcus hirae (Streptococcus faecium) ATCC 9790 (II), and Leuconostoc mesenteroides DMS 20343 (III). Lipoteichoic acids II and III are partially substituted by mono-, di-, tri-, and tetra-alpha-D-glucopyranosyl residues with (1----2) interglycosidic linkages. Lipoteichoic acid I is substituted with alpha-kojibiosyl residues only. Lipoteichoic acids I and III additionally carry D-alanine ester. Lipoteichoic acids were separated on columns of concanavalin-A-Sepharose according to their increasing number of glycosyl substituents per chain. It was evident that all molecular species are usually glycosylated and that alanine ester and glycosyl residues occur on the same chains. The chain lengths of lipoteichoic acid I and II vary between 9-40 glycerophosphate residues, whereas those of lipoteichoic acid III appear to be uniform (33 +/- 2 residues). Molecular species differ in the extent of glycosylation but their content of alanyl residues is fairly constant. All lipoteichoic acids contain a small fraction (5-15%) different in composition from the bulk and most likely reflecting an early stage of biosynthesis. Two procedures for chain length determination of poly(glycerophosphate) lipoteichoic acids are described.  相似文献   

17.
Membrane preparations, obtained from Bacillus strains which have N-acetylglucosamine-linked lipoteichoic acids in their membranes, were shown to catalyze the transfer of N-[14C]acetylglucosamine (GlcNAc) from beta-[14C]GlcNAc-P-undecaprenol to endogenous polymer. In this reaction, alpha-GlcNAc-P-undecaprenol or alpha-GlcNAc-PP-undecaprenol could not substitute for beta-GlcNAc-P-undecaprenol as the N-acetylglucosamine donor. This enzyme was most active at pH 6.0 and in the presence of 40 mM MgCl2. The apparent Km for beta-GlcNAc-P-undecaprenol was 2 microM. The radioactive polymer products, solubilized by hot phenol treatment, coincided with lipoteichoic acids in chromatographic behavior. Hydrogen fluoride treatment of the polymer products gave a major fragment identical with GlcNAc(alpha 1----2)glycerol, which corresponded to the dephosphorylated repeating units of the lipoteichoic acids in the examined strains. Thus it is concluded that beta-GlcNAc-P-undecaprenol serves as the donor of N-acetylglucosamine in the biosynthesis of lipoteichoic acids in a group of Bacillus strains.  相似文献   

18.
Polysialoglycoproteins (PSGP) we first isolated from the unfertilized eggs of rainbow trout (Salmo gairderi) and now found to be a ubiquitous component of Salmonidae fish eggs are a novel type of glycoprotein. PSGP from rainbow trout has a molecular weight of 200 X 10(3), a low protein content (about 15% w/w), and a high sialic acid (N-glycolylneuraminic acid (NeuGc] content (about 60%, w/w). In any evaluation of the biological functions of PSGP, information about the complete structure of this unique macromolecular component is relevant. We have now completed the determination of the overall structural organization of the 200-kDa PSGP, and this is the first report of the complete structural analysis of this novel class of glycoprotein: (Asp)0-2-Ala-Thr*-Ser*-Glu-(Ala-Ala-Thr*-Gly-Pro-Ser-Gly-Asp-Asp-Ala-Thr *-Ser*- Glu)n-Ala-Ala-Thr*-Gly-Pro-Ser-Gly where * indicates the amino acid residues to which oligo- and/or polysialylglycan units are attached and n = 25. Thus the most outstanding structural features of PSGP isolated from the unfertilized eggs of rainbow trout are now the occurrence of (a) tandem repeats of a tridecapeptide and (b) an alpha-2----8-linked oligo(poly)sialyl group on each of the core oligosaccharide chains, i.e. GalNAc- beta 1----4(NeuGc alpha 2----3)GalNAc beta 1----3Gal beta 1----4Gal beta 1----3[----8NeuGc alpha 2)n----6)GalNAc alpha 1----Ser (or Thr), Fuc alpha 1----3GalNAc beta 1----3Gal beta 1----4Gal beta 1----3[----8NeuGc alpha 2)n ----6)GalNAc alpha 1----Ser (or Thr), GalNAc beta 1----3Gal beta 1----4Gal beta 1----3[----8NeuGc alpha 2)n----6)GalNAc alpha 1----Ser (or Thr), Gal beta 1----4Gal beta 1----3[----8NeuGc alpha 2)n----6)GalNAc alpha 1----Ser (or Thr), and Gal beta 1----3[----8NeuGc alpha 2)n----6) GalNAc alpha 1----Ser (or Thr).  相似文献   

19.
Structural studies were carried out on the teichoic acids in cell walls of Listeria monocytogenes serotypes 3a, 4b, 4f, 6, and 7. The structure of the dephosphorylated repeating units, obtained by treatment with 46% hydrogen fluoride or alkaline hydrolysis, was examined by methylation analysis, acetolysis, and 1H-NMR spectroscopy. The results of Smith degradation of the teichoic acids and 13C-NMR spectroscopy led to the following most likely structures of the repeating units of the teichoic acids:----1-[N-acetylglucosaminyl(alpha 1----4)]ribitol-5-phosphate----for serotype 3a,----4-[galactosyl(alpha 1----6)][glucosyl(beta 1----3)]N -acetylglucosaminyl(beta 1----2)ribitol-5-phosphate----for serotype 4b,----4-[galactosyl(alpha 1----6)][N -acetylglucosaminyl(alpha 1----3)]N-acetylglucosaminyl(beta 1----2)ribitol -5-phosphate----for serotype 4f,----4-N-acetylglucosaminyl(beta 1----4)ribitol -5-phosphate----for serotype 6, and----1-ribitol-5-phosphate----for serotype 7. About 40% of the repeating units of the teichoic acid from serotype 4f were not substituted at C-3 of beta-N-acetylglucosaminyl residues.  相似文献   

20.
Lipopolysaccharides from Yersinia enterocolitica serovars O:1,2a,3, O:2a,2b,3 and O:3 have been isolated and characterized. 6-Deoxy-L-altrose residues were shown to be the main constituents of lipopolysaccharides isolated in addition to residues of L-rhamnose, D-glucose, D-galactose, 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-D-galactose, D-glycero-D-manno-heptose and L-glycero-D-manno-heptose, 3-deoxy-D-manno-octulosonic acid being minor components of sugar chains. Mild hydrolysis of lipopolysaccharides with acetic acid furnished O-specific polysaccharides, which are composed of 6-deoxy-L-altrose. Using 13C-NMR spectroscopy and methylation data, the structural features of backbones have been elucidated as follows: ----2)-6d-L-Altp(beta 1----2)-6d-L-Altp(beta 1----3)-6d-L-Altp)(beta 1----for serovars O:1,2a,3 and O:2a,2b,3;----2)-6d-L-Altp(beta 1----for serovar O:3. In addition, O-polysaccharide of serovar O:2a,2b,3 was found to contain an O-acetyl group at the C-3 position of some 1,2-linked sugar residues.  相似文献   

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