首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Unsubstituted 1,3-poly(glycerol phosphate) and two sugar-1-phosphate polymers were identified in the cell wall of Brevibacterium linens VKM Ac-2159 by NMR spectroscopy and chemical methods. A monomer of one of the sugar-1-phosphate polymers has the branched repeating unit of the following structure: -4)-[beta-D-GlcpNAc-(1-->3)]-alpha-D-Glcp-(1-P-. The repeating unit of another sugar-1-phosphate polymer has a linear structure consisting of alternating beta- and alpha-N-acetylglucosamine residues: -4)-beta-D-GlcpNAc-(1-->6)-alpha-D-GlcpNAc-(1-P-. Some part of the beta-N-acetylglucosaminyl residues bear O-ester-bound succinic acid residues at C-3. The identified sugar-1-phosphate polymers have not been described earlier in cell walls of other bacteria.  相似文献   

2.
The cell wall of Spirilliplanes yamanashiensis VKM Ac-1993(T) contains four anionic polymers, viz., three teichoic acids and a sugar-1-phosphate polymer. The following are the structures of the teichoic acids: poly[-6-beta-D-glucopyranosyl-(1-->2)-glycerol phosphate] (PI), 1,3-poly(glycerol phosphate) bearing N-acetyl-alpha-D-glucosamine residues at O-2 (70%) (PII), and poly[-6-N-acetyl-alpha-D-glucosaminyl-(1-->2)-glycerol phosphate] (PIII). The repeating unit of the fourth polymer (PIV) has the structure of -6-alpha-D-GlcpNAc-(1-->6)-alpha-D-GlcpNAc-1-P- with a 3-O-methyl-alpha-D-mannopyranosyl residues at position 3 of some 6-phosphorylated N-acetylglucosamine residues (50%). Polymers PI, PIII and PIV have not hitherto been found in prokaryotic cell walls.  相似文献   

3.
The cell walls of two streptoverticille genospecies which belong to a historically isolated group of the genus Streptomyces contain anionic polymers of different structure. Streptomyces hachijoensis VKM Ac-191T and Streptomyces cinnamoneus subsp. azacoluta VKM Ac-606T assigned to one genospecies on the basis of DNA--DNA hybridization [5] contain 37% of an identical sugar-1-phosphate polymer. The repeating disaccharide units of the polymer, 2-amino-2-deoxy-alpha-D-glucopyranosyl-(1-->6)-2-acetamido-2-deoxy-al pha-D-glucopyranose, are linked at C-1 and C-6' by phosphodiester bonds. The cell walls of Streptomyces biverticillatus VKM Ac-891T and Streptomyces baldaccii VKM Ac-821T, members of another genospecies, contain about 30% 1,3-poly(glycerol phosphate) completely substituted by 2-amino-2-deoxy-alpha-D-glucopyranosyl residues at C-2. Due to the presence of an amino sugar with a free amino group in the repeating unit, the polymers exhibit neutral properties. Polymer structures were determined by chemical methods and NMR spectroscopy. The data indicate taxonomic specificity of anionic polymers in streptoverticille cell walls.  相似文献   

4.
Paracoccidioides brasiliensis is a pathogenic dimorphic fungus causing paracoccidioidomycosis, the most widespread systemic mycosis in Latin America. We have studied the structure of the alkali-extracted water-soluble cell wall polysaccharides (F1SS) from both mycelial and yeast phases of this fungus by using chemical analysis and NMR spectroscopic techniques. The F1SS polysaccharide from the mycelial phase consists of a trisaccharidic repeating unit of -->6)-[alpha-Galf -(1-->6)-alpha-Manp-(1-->2)]-alpha-Manp-(1-->. The F1SS polysaccharide of the yeast phase maintains 10% of the structure of the mycelium phase, but the main structure contain a disaccharide repeating unit of -->6)-[-alpha-Manp-(1-->2)]-alpha-Manp-(1-->, alternating with a trisaccharide repeating block of -->6)-[beta-Galf -(1-->6)-alpha-Manp-(1-->2)]-alpha-Manp-(1-->.  相似文献   

5.
The Rhizobium sp. T1 strain. which induces nodule formation on alfalfa and clover roots, produces, during growth, an extracellular polysaccharide composed of D-glucose and D-glucuronic acid noted glucoglucuronan. During the bacterial growth, the pH of the medium decreases slightly. The control of pH in the growth medium slightly reduces the glucoglucuronan production. Under the conditions tested in the present work, the weight-average molecular weight of the polymers produced with or without pH control are similar: Mw approximately 2 x 10(6); the repeating unit determined by chemical and NMR analyses corresponds to the disaccharide: --> 3)-beta-D-GlcpA-(1-->4)-beta-D-Glcp-(1 -->.  相似文献   

6.
The major cell wall polymer of Kineosporia aurantiaca VKM Ac-702T a representative of the suborder Frankineae, is a galactomannan with a repeating unit of the following structure: -->3)-beta-D-Galp-(1-->6)-beta-D-Manp-(1-->4)-beta-D-Manp-(1-->3)-beta-D-Galp-(1-->4)-beta-D-Manp-(1-->4)-beta-D-Manp-(1--> that has not been reported so far. This was established using chemical degradation methods and NMR spectroscopy. The polysaccharide identified in the present study provides the second example of neutral galactomannans in actinomycete cell walls. The cell wall of K. aurantiaca VKM Ac-702T also contains a minor teichoic acid, viz., 1,3-poly(glycerol phosphate) partially substituted with alpha-glucosamine residues, only part of which are N-acetylated.  相似文献   

7.
The structure of the O-antigen polysaccharide from Escherichia coli O172 has been determined. In combination with sugar analysis, NMR spectroscopy shows that the polysaccharide is composed of pentasaccharide repeating units. Sequential information was obtained by mass spectrometry and two-dimensional NMR techniques. An O-acetyl group was present as 0.7 equivalent per repeating unit. Treatment of the O-deacetylated polysaccharide with aqueous 48% hydrofluoric acid rendered cleavage of the phosphodiester in the backbone of the polymer and the pentasaccharide isolated after gel permeation chromatography was structurally characterized. Subsequent NMR experiments on polymeric materials revealed the structure of the repeating unit of the O-polysaccharide from E. coli O172 as:-->P-4)-alpha-D-Glcp-(1-->3)-alpha-L-FucpNAc-(1-->3)-alpha-D- GlcpNAc-(1-->3)-alpha-L-FucpNAc-(1-->4)-alpha-D-Glcp6Ac-(1-->  相似文献   

8.
Structures of cell wall anionic polymers of the strain Streptomyces sp. VKM Ac-2124, a causative agent of potato scab, which is phylogenetically the closest to plant pathogenic species S. setonii and S. caviscabies, were studied. The strain contains three anionic glycopolymers, viz., a teichuronic acid with a disaccharide repeating unit -->6)-alpha-d-Glcp-(1-->4)-beta-d-ManpNAc3NAcA-(1-->, a beta-glucosylated polymer of 3-deoxy-d-glycero-d-galacto-non-2-ulopyranosonic acid (Kdn), and a beta-glucosylated 1,5-poly(ribitol phosphate). The strain studied is the second representative of plant pathogenic streptomycetes inducing potato scab disease, the cell wall anionic polymers of which were shown to contain a Kdn-polymer. Presumably, the presence of Kdn-containing structures in the surface regions of pathogens is essential for their efficient attachment to host plant cells.  相似文献   

9.
The O-specific polysaccharide chain (O-antigen) of the lipopolysaccharide (LPS) of Providencia stuartii O49 was studied using sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including two-dimensional COSY, TOCSY, ROESY, H-detected 1H, 13C HSQC and HMBC experiments. The polysaccharide was found to have the trisaccharide repeating unit with the following structure: -->6)-beta-D-Galp(1-->3)-beta-D-GalpNAc(1-->4)-alpha-D-Galp(1-->  相似文献   

10.
The structure of the O-specific polysaccharide isolated by mild acid hydrolysis of the lipopolysaccharide of Mesorhizobium huakuii IFO15243T was studied using methylation analysis and various one- and two-dimensional 1H and 13C NMR experiments. The O-antigen polysaccharide was found to be linear polymer constituted by a trisaccharide repeating unit of the following structure: --> 2)-alpha-L-6dTalp-(1 --> 3)-alpha-L-6dTalp-(1 --> 2)-alpha-L-Rhap-(1 -->.  相似文献   

11.
This report describes the determination of the complete primary structure of the adhesin receptor polysaccharide of Streptococcus oralis ATCC 55229 (previously characterized as Streptococcus sanguis H1), a Gram-positive bacteria implicated in dental plaque formation. The polysaccharide was isolated from S. oralis ATCC 55229 cells after deproteination, enzymatic hydrolysis, and ion exchange chromatography. It was shown to consist of rhamnose, galactose, glucose, glycerol, and phosphate, in molar ratios of 2:3:1:1:1. Sequence and linkage assignments of the glycosyl residues were obtained by methylation analysis followed by gas-liquid chromatography and electron-impact mass spectrometry. 31P NMR spectroscopy revealed that phosphate was present in a diester, connecting glycerol to one of the galactosyl residues. High-performance liquid chromatography of a partial acid hydrolysate of the polysaccharide confirmed this finding by showing galactose 6-phosphate and glycerol 1-phosphate. The structural determination was completed by the combination of two-dimensional homonuclear Hartmann-Hahn and NOE experiments and heteronuclear [1H,13C] and [1H,31P] multiple-quantum coherence experiments. Thus, the adhesin receptor polysaccharide of S. oralis ATCC 55229 was found to be a polymer composed of hexasaccharide repeating units that contain glycerol linked through a phosphodiester to C6 of the alpha-galactopyranosyl residue and are joined end-to-end through galactofuranosyl-beta(1-->3)-rhamnopyranosyl linkages: [formula: see text] This structure is novel among bacterial cell surface polysaccharides in general and specifically among those implicated in dental plaque formation.  相似文献   

12.
The exopolysaccharide produced by Streptococcus thermophilus 8S in reconstituted skimmed milk is a heteropolysaccharide containing d-galactose, d-glucose, d-ribose, and N-acetyl-d-galactosamine in a molar ratio of 2 : 1 : 1 : 1. Furthermore, the polysaccharide contains one equivalent of a novel open chain nononic acid constituent, 3,9-dideoxy-d-threo-d-altro-nononic acid, ether-linked via C-2 to C-6 of an additional d-glucose per repeating unit. Methylation analysis and 1D/2D NMR studies (1H and 13C) performed on the native polysaccharide, and mass spectrometric and NMR analyses of the oligosaccharide obtained from the polysaccharide by de-N-acetylation followed by deamination and reduction demonstrated the 'hepta'saccharide repeating unit to be: -->4)-alpha-D-Galp-(1-->2)-beta-D-Ribf-(1-->4)-beta-D-Galp-(1-->4)-beta-D-Glcp-(1--7')-Sub-(1-->4)-beta-D-GalpNAc-(1--> in which Sug is 6-O-(3',9'-dideoxy-d-threo-d-altro-nononic acid-2'-yl)-alpha-d-glucopyranose.  相似文献   

13.
An acidic O-specific polysaccharide was isolated from Hafnia alvei PCM 1196 lipopolysaccharide and studied by sugar and methylation analyses along with one- and two-dimensional 1H and 13C NMR spectroscopy, including NOESY and HMBC experiments. The following structure of the pentasaccharide repeating unit was established: -->4)-alpha-D-GalpA-(1-->3)-beta-D-GlcpNAc-(1-->2)-beta-D-Galp-(1-->6)-alpha-D-Glcp-(1-->6)-alpha-D-GlcpNAc-(1-->.  相似文献   

14.
Teichoic acid and disaccharide-1-phosphate polymer were identified in the cell walls of Bacillus subtilis subsp. subtilis VKM B-501T. The teichoic acid represents 1,3-poly(glycerol phosphate) 80% substituted by α-D-glucopyranose residues at O-2 of glycerol. The linear repeating unit of disaccharide-1-phosphate polymer contains the residues of β-D-glucopyranose, N-acetyl-α-D-galactosamine, and phosphate and has the following structure: -6)-β-D-Glcp-(1→3)-α-D-GalpNAc-(1-P-. The structures of two anionic polymers were determined by chemical and NMR-spectroscopic methods. The 1H- and 13C-NMR spectral data on disaccharide-1-phosphate polymer are presented for the first time.  相似文献   

15.
Smooth-type lipopolysaccharide (LPS) of Burkholderia pseudomallei has been reported to contain two kinds of O-antigenic polysaccharides, a 1,3-linked homopolymer of 6-deoxy-heptose and a polymer with a repeating unit of -->3)-glucose-(1-->3)-6-deoxy-talose-(1--> with O-acetyl or O-methyl modifications. A LPS preparation containing these two polysaccharides was separated by gel-permeation chromatography in this study. Chemical analysis of the separated fractions revealed the 6-deoxy-heptan [corrected] to be a polysaccharide without a lipid portion and the polymer of glucose and 6-deoxy-talose to be an O-antigenic polysaccharide of the LPS. This result was further supported by the assay of these polysaccharide molecules for macrophage activation activity. The 6-deoxy-heptan [corrected] showed no macrophage activation, indicating that this polysaccharide was not the LPS, but one of the capsular polysaccharides of B. pseudomallei.  相似文献   

16.
As part of our ongoing investigations involving lectinmediatedadhesion among oral bacteria, the receptor polysaccharide fromStreptococcus gordonii 38 was isolated and characterized. Carbohydrateanalysis of the hydrolysed S.gordonii 38 polysaccharide by high-performanceanionexchange chromatography with pulsed amperometric detection(HPAEC-PAD) showed galactose (Gal) (2 mol), N-acetylgalactosamine(GalNAc) (1 mol), rhamnose (Rha) (2 mol), glucose (Glc) (1 mol)and galactosamine-6-phosphate (1 mol). Mild acid hydrolysisof the polysaccharide yielded a heptasaccharide repeating unit.The structure of the heptasaccharide repeating unit was determinedby high-resolution NMR spectroscopy which includes various homonuclear(DOF—COSY, TQF-COSY, NOESY and HOHAHA) and heteronuclearexperiments (HMQC), including linkage assignments by 1H-13Clong-range correlation (HMBC). Complete 1H and 13C NMR assignmentsfor the intact polysaccharide yielded the covalent structureof a heptasaccharide repeating unit:  相似文献   

17.
The lipopolysaccharide of Plesiomonas shigelloides serotype O74:H5 (strain CNCTC 144/92) was obtained with the hot phenol/water method, but unlike most of the S-type enterobacterial lipopolysaccharides, the O-antigens were preferentially extracted into the phenol phase. The poly- and oligosaccharides released by mild acidic hydrolysis of the lipopolysaccharide from both phenol and water phases were separated and investigated by (1)H and (13)C NMR spectroscopy, MALDI-TOF mass spectrometry, and sugar and methylation analysis. The O-specific polysaccharide and oligosaccharides consisting of the core, the core with one repeating unit, and the core with two repeating units were isolated. It was concluded that the O-specific polysaccharide is composed of a trisaccharide repeating unit with the [-->2)-beta-d-Quip3NAcyl-(1-->3)-alpha-l-Rhap2OAc-(1-->3)-alpha-d-FucpNAc-(1-->] structure, in which d-Qui3NAcyl is 3-amino-3,6-dideoxy-d-glucose acylated with 3-hydroxy-2,3-dimethyl-5-oxopyrrolidine-2-carboxylic acid. The major oligosaccharide consisted of a single repeating unit and a core oligosaccharide. This undecasaccharide contains information about the biological repeating unit and the type and position of the linkage between the O-specific chain and core. The presence of a terminal beta-d-Quip3NAcyl-(1--> residue and the -->3)-beta-d-FucpNAc-(1-->4)-alpha-d-GalpA element showed the structure of the biological repeating unit of the O-antigen and the substitution position to the core. The -->3)-beta-d-FucpNAc-(1--> residue has the anomeric configuration inverted compared to the same residue in the repeating unit. The core oligosaccharide was composed of a nonphosphorylated octasaccharide, which represents a novel core type of P. shigelloides LPS characteristic of serotype O74. The similarity between the isolated O-specific polysaccharide and that found on intact bacterial cells and lipopolysaccharide was confirmed by HR-MAS NMR experiments.  相似文献   

18.
Zeng Y  Kong F 《Carbohydrate research》2004,339(8):1503-1510
Syntheses of a hexasaccharide, the dimer of the repeating unit of the group E streptococci polysaccharide, and a tetrasaccharide, the repeating unit of the E. coli O7:K98:H6, were achieved by constructing alternate alpha-L-(1-->2)- and alpha-L-(1-->3)-linked L-rhamnopyranose backbones and substituting with beta-linked D-glucopyranose side chains for the former, and a D-glucopyranosyluronate branch for the latter, respectively, at O-2 of the L-rhamnose ring.  相似文献   

19.
An acidic polysaccharide was isolated from Pseudoalteromonas flavipulchra type strain NCIMB 2033(T) and found to consist of 6-deoxy-L-talose (L-6dTal), D-galactose and 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo). The identities of the monosaccharides were ascertained by sugar analysis and 1D 1H and 13C NMR spectroscopy in conjunction with 2D COSY, TOCSY, ROESY and 1H, 13C HMQC experiments, which enabled determination of the following structure of the trisaccharide repeating unit of the polysaccharide:-->3)-alpha-L-6dTalp4Ac-(1-->3)-beta-D-Galp-(1-->7)-alpha-Kdop-(2-->.  相似文献   

20.
An O-specific polysaccharide was isolated from the lipopolysaccharide of a plant-growth-promoting bacterium Azospirillum brasilense Sp245 and studied by sugar analyses along with one- and two-dimensional 1H and 13C NMR spectroscopy, including NOESY. The polysaccharide was found to be a new rhamnan with a pentasaccharide repeating unit having the following structure:-->2)-beta-D-Rhap-(1-->3)-alpha-D-Rhap-(1-->3)-alpha-D-Rhap-(1-->2)-alpha-D-Rhap-(1-->2)-alpha-D-Rhap-(1-->  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号