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1.
Cell-wall lipopolysaccharide isolated from Pasteurella haemolytica serotype T3 using the phenol-water extraction procedure was shown to be an S type lipopolysaccharide by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Hydrolysis with mild acid afforded a lipid-free, antigenic O-chain polysaccharide. On the basis of one- and two-dimensional 1H and 13C nuclear magnetic resonance studies, in conjunction with microanalytical chemical methods, the O-polysaccharide was determined to be a linear polymer of a disaccharide repeating unit having the structure. [----3)-beta-D-G1cpNAc-(1----4)-alpha-L-Rhap-(1----]n  相似文献   

2.
Capsular polysaccharide from two strains of Pasteurella haemolytica serotype T15 was purified and characterized by chemical analysis and NMR spectroscopy. The polymer, a teichoic acid, proved to be very similar in structure to the capsular polysaccharide of P. haemolytica serotype T4 and identical to the previously described K62 (K2ab) capsular polysaccharide of Escherichia coli, and the capsular polysaccharide of Neisseria meningitidis serotype H, i.e. ----(2-glycerol-3)----(phosphate)----(4-alpha-D-galactopyranose -1)---- with partial O-acetylation on the galactose residues. Electron microscopy with Protein A-gold labelled antisera showed that the polysaccharide was peripherally located on the surface of all three organisms. Chemical removal of O-acetyl groups from the polysaccharide yielded a structure identical to that previously described for E. coli K2 (K2a). Both O-acetylated and de-O-acetylated P. haemolytica T15 polymers, when absorbed on to sheep erythrocytes in passive haemagglutination assays, yielded identical antibody titres with sera raised against P. haemolytica T15, E. coli K2 or N. meningitidis H whole cells. De-O-acetylation of the Pasteurella polysaccharide influenced its precipitability with immune sera, but this could not be related to the absence of O-acetyl groups because the non-acetylated E. coli K2 polymer readily precipitated with a line of 'identity' with the acetylated P. haemolytica T15 polymer.  相似文献   

3.
The serotype-specific capsular polysaccharide from two strains of Pasteurella haemolytica serotype T4 organisms was purified and characterized by chemical analysis and NMR spectroscopy. The polymer, a teichoic acid, has the backbone structure ----(2-glycerol-l)----(phosphate)----(6-alpha-D-galactose-1)---- and is partially O-acetylated on the C2 and C3 galactose residues. Chemical removal of O-acetyl groups from the polysaccharide destroyed both its ability to precipitate with antiserum raised against killed whole serotype T4 organisms and its ability to adhere to sheep erythrocytes in passive haemagglutination experiments. Attempts to elicit antisera using the purified polymer were unsuccessful but a partially purified material was immunogenic.  相似文献   

4.
The chemical structure of the polysaccharide moiety of the lipopolysaccharide Rhodopseudomonas sphaeroides ATCC 17023 was established. Mild acetic acid hydrolysis of isolated lipopolysaccharide, followed by preparative high-voltage paper electrophoresis afforded three oligosaccharides. They were characterized by chemical and physicochemical studies to be: GlcA(alpha 1----4)dOclA8P, Thr(6') GlcA(alpha 1----4)GlcA and GlcA(alpha 1----4)dOclA, where GlcA is D-glucuronic acid and dOc1A is 3-deoxy-D-manno-octulosonic acid. Carboxyl-reduction of the lipopolysaccharide followed by acid hydrolysis gave a trisaccharide: GlcA(alpha 1----4)Glc(alpha 1----4)Glc, showing the presence of three residues of glucuronic acids in the O-specific chain and indicating that only two of them are reducible by NaBH4. The linkage between the polysaccharide and lipid A was shown to be through a single 1,4-linked residue of dOc1A attached by a 2,6'-linkage to the lipid A moiety.  相似文献   

5.
The 1H- and 13C-NMR parameters, chemical shifts and coupling constants, for the pentasaccharide of the genus-specific epitope of Chlamydia lipopolysaccharide and related di-, tri-, and tetra-saccharides have been measured and assigned completely using 1D and 2D techniques, and their structures have been confirmed. NOE experiments indicated the preferred conformation of the pentasaccharide and the component oligosaccharides. The 3JH,H demonstrate a change in conformation by rotation of the C-6-C-7 bond of the side chain of the (2----8)-linked Kdo (unit b) in alpha-Kdo-(2----8)-alpha-Kdo-(2----4)-alpha-Kdo-(2----6)-beta-GlcN-(1--- -6)- GlcNol, alpha-Kdo-(2----8)-alpha-Kdo-(2----4)-alpha-Kdo-(2----6)-beta-GlcNAc-(1- ---O)- allyl, and alpha-Kdo-(2----8)-alpha-Kdo-(2----4)-alpha-Kdo-(2----O)-allyl relative to that preferred in alpha-Kdo-(2----4)-alpha-Kdo-(2----6)-beta-GlcNAc-(1----O)-allyl, alpha-Kdo-(2----8)-alpha-Kdo-(2----O)-allyl, alpha-Kdo-(2----4)-alpha-Kdo-(2----O)-allyl, and alpha-Kdo-(2----6)-beta-GlcNAc-(1----O)-allyl, irrespective of the size of the aglycon, e.g., allyl or beta-D-GlcN residues. The conformational results have been substantiated by computer calculations using the HSEA approach.  相似文献   

6.
The sidechain of the lipopolysaccharide from the phytopathogen Pseudomonas syringae pv. morsprunorum C28 was shown to be composed of D-rhamnose. Using 1H and 13C-NMR spectroscopy, methylation analysis, Smith degradation and optical rotation data, the repeat unit was found to have the structure: ----3)-D-Rhap-(alpha 1----3)-D-Rhap-(alpha 1----2)-D-Rhap-(alpha 1---- and a degree of polymerization of approximately 70. Attention is drawn to the possible prevalence of D-6-deoxyhexoses in the lipopolysaccharides of plant pathogenic bacteria.  相似文献   

7.
Both a neutral and an acidic polymer have been isolated from a lipopolysaccharide extract of the reference strain for Serratia marcescens serogroup O22. The neutral polymer has a linear structure with the repeating unit shown. The same tetrasaccharide unit also forms the backbone of the branched neutral polymer isolated from the reference strain for serogroup O10, which cross-reacts strongly with O22. ----2)-alpha-L-Rhap-(1----2)-alpha-L-Rhap-(1----3)-alpha-L-+ ++Rhap-(1----3)-alpha- D-GlcpNAc-(1----  相似文献   

8.
The O-specific polysaccharide chain of the Pseudomonas aurantiaca IMV 31 lipopolysaccharide contains N-acetyl-L-fucosamine (FucNAc) and di-N-acetyl-D-bacillosamine (2,4-diacetamido-2,4,6-trideoxyglucose, Bac(NAc)2) in the ratio 2:1. On the basis of methylation, solvolysis with anhydrous hydrogen fluoride, and computer-assisted analysis of 13C-NMR spectrum, it was concluded that the trisaccharide repeating unit of the polysaccharide possesses the following structure: structure: ----3)-beta-D-Bac(NAc)2-(1----3)-alpha-L-FucNAc-(1----3)-alpha-L- FucNAc-(1----.  相似文献   

9.
A murine hybridoma cell line that produces monoclonal antibody (mAb) against the serogroup D1 Salmonella lipopolysaccharide (LPS) antigen was established. The trisaccharide tyvelose alpha 1----3 mannose alpha 1----4 rhamnose was shown to be involved in the reactive epitope of the mAb since this mAb reacted strongly with strains of serogroup D1 Salmonella but not with Salmonella strains from the O serogroups of A, B, and D2, and sodium meta-periodate was found to destroy the reactivity of the serogroup D1 O-antigen with the mAb. As such this mAb was found to be a useful serotyping reagent for the identification of serogroup D1 Salmonella, and for the differentiation of strains of serogroups D1 and D2 Salmonella which have identical flagellar H antigens.  相似文献   

10.
O-Specific polysaccharide, consisting of D-rhamnose and L-glycero-D-manno-heptose (LD-Hep) in a 2 : 1 ratio, was obtained on the mild acid degradation of the Pseudomonas cepacia IMV 673/2 lipopolysaccharide; monosaccharide LD-Hep has not previously been found in O-specific chains of lipopolysaccharides. On the basis of methylation and 13C-NMR data, it was concluded that the polysaccharide is composed of trisaccharide repeating units having the following structure: ----3)-alpha-D-Rha-(1----3)-alpha-D-Rha-(1----2)-alpha-LD-Hep-(1----  相似文献   

11.
Polymeric material isolated from the lipopolysaccharide of the reference strain of Pseudomonas cepacia serogroup O1 consisted mainly of D-glucose and 2-amino-2-deoxy-L-glucose: rhamnose and O-acetyl groups were also present. As a result of spectroscopic and degradative studies, the disaccharide repeating-unit shown could be assigned to the major polymer present. A possible origin of the minor components is suggested. ----4)-alpha-D-Glcp-(1----3)-alpha-L-GlcpNAc-(1----.  相似文献   

12.
Cross-reactivity between fungal and Trypanosoma cruzi polysaccharides, owing to common residues of beta-D-galactofuranose, beta-D-galactopyranose, and alpha-D-mannopyranose, was demonstrated by using rabbit immune sera against T. cruzi epimastigotes and sera from patients with Chagas' disease. Several chagasic (Ch) sera precipitated partly purified galactomannans from Aspergillus fumigatus and from T. cruzi epimastigotes and also the galactoglucomannan from Dactylium dendroides. Reaction of one Ch serum with T. cruzi galactomannan (GM) was completely inhibited by synthetic beta-D-Galf-(1----3)-Me alpha-D-Manp, and that of another Ch serum with a purified D. dendroides galactoglucomannan (GGM) was partly inhibited by (1----6)-linked (81%) or by (1----3)-linked (33%) beta-D-Galf-Me alpha-D-Manp. The beta-D-Galf-(1----3)-alpha-D-Manp epitope was present in both T. cruzi and D. dendroides polysaccharides. Rabbit anti-T. cruzi antisera precipitated A. fumigatus GM, T. cruzi antigenic extracts containing the lipopeptidophosphoglycan (LPPG), T. cruzi alkali-extracted GM, a synthetic GM, and D. dendroides GGM. Weak reactivities were obtained for a Torulopsis lactis-condensi GM containing beta-D-Galp terminal residues and for baker's yeast mannan with alpha-D-Manp-(1----3)-alpha-D-Manp-(1----2)-alpha-D-Manp+ ++-(1----2) side chains. An anti-LPPG rabbit serum precipitated D. dendroides GGM--a reaction inhibited (82%) by beta-D-Galf-(1----3)-Me alpha-D-Manp and. less efficiently, by a (1----5)-linked beta-D-Galf-tetrasaccharide. Sera from mice immunized with D. dendroides whole cells reacted with CL-strain trypomastigotes as shown by indirect immunofluorescence, by a Staphylococcus adherence test, but were not lytic. Mice immunized with D. dendroides were not protected against a challenge with virulent T. cruzi trypomastigotes.  相似文献   

13.
The structure of the O-specific side-chains of the Escherichia coli O2 lipopolysaccharide has been investigated, different 1H- and 13C-n.m.r. techniques being the main methods used. It is concluded that they are composed of pentasaccharide repeating-units having the following structure, in which D-Fuc3NAc is 3-acetamido-3,6-dideoxy-D-galactose. ----4)-beta-D-GlcpNAc-(1----3)-alpha-L-Rhap-(1----2)-alpha-L-Rh ap-(1----3)-beta-L-Rhap-(1----2 increases 1 alpha-D-Fucp3NAc.  相似文献   

14.
The rfb gene, involved in the synthesis of the O-specific polysaccharide (a mannose homopolymer) of Escherichia coli O9 lipopolysaccharide (LPS), was cloned in E. coli K-12 strains. The O9-specific polysaccharide covalently linked to the R core of K-12 was extracted from the K-12 strains harboring the O9 rfb gene. All the other genes required for the synthesis of rfe-dependent LPS are therefore considered to be present in the K-12 strains. It was found that bacteria harboring some clones with deletions of the ca. 20-kilobase-pair (kbp) BglII-StuI fragment no longer synthesized the O9-specific polysaccharide. However, bacteria harboring clones del 21, del 22, and del 25, which carry deletions of the 10-kbp PstI-StuI fragment, synthesized an O-specific polysaccharide antigenically distinct from E. coli O9 LPS. Although this new O-specific polysaccharide consisted solely of mannose and the mannose residues were combined only through alpha-1,2 linkage, it was still composed of a repeating oligosaccharide unit, possibly a trisaccharide unit,----2)alpha Man-(1----2)alpha Man-(1----2)alpha Man-(1----. It is therefore likely that this new O-specific polysaccharide was derived from a part of the O9-specific polysaccharide----3)alpha Man-(1----3)alpha Man-(1----2)alpha Man-(1----2)alpha Man-(1----2)alpha Man-(1----and that the deleted part of the clones was responsible for the synthesis of alpha-1,3 linkages of the O9-specific polysaccharide.  相似文献   

15.
Structure of the O-antigen of Francisella tularensis strain 15.   总被引:2,自引:0,他引:2  
The O-specific polysaccharide, obtained by mild acid degradation of the lipopolysaccharide of Francisella tularensis strain 15, contained 2-acetamido-2,6-dideoxy-D-glucose (D-QuiNAc), 4,6-dideoxy-4-formamido-D-glucose (D-Qui4NFm), and 2-acetamido-2-deoxy-D-galacturonamide (D-GalNAcAN) in the ratios 1:1:2. Tri- and tetra-saccharide fragments were obtained on treatment of the polysaccharide with anhydrous hydrogen fluoride and partial hydrolysis with 0.1 M hydrochloric acid, respectively. On the basis of 1H- and 13C-n.m.r. spectroscopy of the polysaccharide and the saccharides, it was concluded that the O-antigen had the structure: ----4)-alpha-D-GalpNAcAN-(1----4)-alpha-D-GalpNAcAN-(1----3) -beta-D-QuipNAc-(1----2)-beta-D-Quip4NFm-(1----. This O-antigen is related in structure to those of Pseudomonas aeruginosa O6, immunotype 1, and IID 1008, and Shigella dysenteriae type 7.  相似文献   

16.
The polysaccharide chain of Proteus vulgaris O19 lipopolysaccharide contains D-galactose, N-acetyl-D-glucosamine N-acetyl-D-galactosamine and N-acetyl-L-fucosamine in the ratio 1:1:1:1. The structure of the polysaccharide was established by full acid hydrolysis and methylation analysis, as well as by non-destructive methods, i.e. the computer-assisted evaluation of the 13C-NMR spectrum and computer-assisted evaluation of the specific optical rotation by Klyne's rule. The polysaccharide is regular and built up of tetrasaccharide repeating units of the following structure: ----3)-alpha-L-FucNAcp-(1----3)-beta-D-GlcNAcp-(1----3)-alph a-D-Galp- (1----4)-alpha-D-GalNAcp-(1---- The O19-antiserum cross-reacts with lipopolysaccharide from P. vulgaris O42, the structure of which is still unknown. No cross-reactions were observed with O-polysaccharides Pseudomonas aeruginosa O7 and Salmonella arizonae O59 in spite of some structural similarities.  相似文献   

17.
We report the completion of the purification of uterine-derived growth factors (UDGF) described previously by this laboratory [Ikeda, T., & Sirbasku, D.A. (1984) J. Biol. Chem. 259, 4049-4064]. During isolation, the mitogenic activity was monitored by using the human MCF-7 breast cancer cells in serum-free Ham's F12 and Dulbecco's modified Eagle's medium (1:1, v/v) containing 15 mM 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (pH 7.2), 200 micrograms/mL bovine serum albumin, and 10 micrograms/mL human transferrin. This medium sustained growth for several days in response to a single addition of growth factor. The isolation of UDGF began with acetic acid extraction followed by sulfopropyl-Sephadex chromatography, Bio-Gel P-10 molecular sieve fractionation, and a series of reverse-phase high-pressure liquid chromatography separations. Purifications [[(1.0-8.5) X 10(6)]-fold] of three mitogens (5-20 ng each) were achieved. The mitogens were shown by protein microsequencing to be DES 1----3 to DES 1----6 forms of insulin-like growth factor I (truncated IGF-I). An Mr estimated by 125I labeling, urea-sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and autoradiography was consistent with a DES 1----3(4) N alpha truncation. Immunoadsorption and radioimmunoassay confirmed immunological properties equivalent to IGF-I. Radioreceptor assays showed truncated IGF-I was functionally equivalent to recombinant IGF-I. The ED50 values of DES 1----3 IGF-I and recombinant IGF-I for MCF-7 cell growth were 0.8-6.0 and 30-150 pg/mL, respectively. With Balb/c 3T3 mouse fibroblasts, the ED50 of DES 1----3 IGF-I was 100 times lower than that of IGF-I. We conclude that the major acid-stable low-Mr mitogenic activities isolated from uterus are very potent forms of truncated IGF-I capable of stimulating growth of epithelial and mesenchymal cells.  相似文献   

18.
The structure of the antigenic O-polysaccharide part of the S-type lipopolysaccharide produced by Actinobacillus pleuropneumoniae serotype 4 has been determined by periodate oxidation, methylation, partial hydrolysis, and 1H- and 13C-n.m.r. spectroscopy. The O-polysaccharide structure has a branched-tetrasaccharide repeating unit, (----3)-beta-D-Galp-(1----4)-[beta-D-Glcp-(1----3)]-beta-D-GalpNAc- (1----4)-alpha-L-Rhap-(1-)n. The structure resembles that of the lipopolysaccharide O-chain of A. pleuropneumoniae serotype 7, and their common epitopes may account for the apparent serological cross-reactivity observed between the two serotypes when incompletely adsorbed, anticapsular-typing sera are used.  相似文献   

19.
The structure of the O-antigen of the lipopolysaccharide from an avirulent strain (M4S) of Pseudomonas solanacearum has been investigated by methylation analysis, n.m.r. spectroscopy, and N-deacetylation-deamination, followed by analysis and controlled Smith-degradation of the product. These studies demonstrate that the O-antigen is composed of a tetrasaccharide repeating-unit having the following structure: ----3)-alpha-D-GlcpNAc-(1----2)-alpha-L-Rhap-(1----2)-alpha- L-Rhap-(1----3)- alpha-L-Rhap-(1----.  相似文献   

20.
On mild acid degradation of the Pseudomonas cepacia strain IMV 4176 lipopolysaccharide, two polysaccharides were obtained, one of which is a homopolymer of N-acetyl-D-galactosamine and the other is composed of equal amounts of N-acetyl-D-galactosamine and D-ribose. Partial hydrolysis with aqueous oxalic acid caused depolymerization of the heteropolysaccharide, and the homopolysaccharide was isolated in the individual state. On the basis of methylation and 13C NMR analysis, it was concluded that both polysaccharides are built up of disaccharide repeating units having the following structures: ----4)-alpha-D-GalpNAc-(1----4)-beta-D-GalpNAc-(1---- and ----4)-alpha-D-GalpNAc-(1----2)-beta-D-Ribf-(1----. The heteropolysaccharide from P. cepacia strain 4176 is identical by the structure of the repeating unit to the O-specific polysaccharide of P. cepacia strain IMV 4202 (serotype 3), Pseudomonas aeruginosa O12 and Serratia marcescens O14.  相似文献   

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