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1.
Carbohydr Res ; 499: 108235, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33461053

RESUMO

Two Pseudomonas strains were isolated from the Ficus elastica leaves. The O-antigens were obtained using phenol-water method and mild acid degradation. The following structures of the O-polysaccharides were established by sugar analysis and 2D NMR spectroscopy: OPS of Pseudomonas psychrotolerans BIM B-1171 G -2)[aDGlcp(1-3)]bDRhap(1-3)aDManp(1-3)aDRhap(1- OPS of Pseudomonas sp. BIM B-1172 G -2)bDRhap(1-3)aDRhap(1-3)[aDGlcp(1-2)]aDRhap(1-.


Assuntos
Ficus/química , Antígenos O/química , Pseudomonas/química , Ficus/microbiologia , Antígenos O/isolamento & purificação , Folhas de Planta/química , Folhas de Planta/microbiologia , Pseudomonas/isolamento & purificação
2.
Carbohydr Res ; 496: 108132, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32861900

RESUMO

Lipopolysaccharide (LPS) was isolated from Pantoea agglomerans 7460 cells by phenol-water extraction. Mild acid degradation allowed to separate OPS and lipid A. Lipid A was analyzed by negative-ion mode ESI MS and found to consist mainly of hexaacylated derivative containing biphosphorylated GlcN disaccharide, four 14:0 (3-OH), 18:0 and 12:0 fatty acids. The structure of the O-specific polysaccharide was established by chemical, NMR and computational methods: The LPS of Р. agglomerans 7460 showed low level of toxicity and pyrogenicity to compare with LPS of E. coli O55:B5 and pyrogenal, respectively. The ability of the modified (succinylated) LPS, which have lost its toxicity, to block the toxic effects of native LPS has been shown.


Assuntos
Antígenos O/química , Pantoea/química , Configuração de Carboidratos , Modelos Moleculares , Antígenos O/isolamento & purificação , Antígenos O/toxicidade , Fenol/química , Fosforilação , Água/química
3.
Biomolecules ; 10(5)2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32456025

RESUMO

The Pantoea agglomerans 8488 lipopolysaccharide (LPS) was isolated, purified and characterized by monosaccharide and fatty acid analysis. The O-polysaccharide and lipid A components of the LPS were separated by mild acid degradation. Lipid A was studied by electrospray ionization mass spectrometry (ESI-MS) and found to consist of hexa-, penta-, tetra- and tri-acylated species. Two-dimensional nuclear magnetic resonance (NMR) spectroscopy revealed the following structure of the O-polysaccharide repeating unit →3)-α-L-Rhap-(1→6)-α-D-Manp-(1→3)-α-L-Fucp-(1→3)-ß-D-GlcNAcp-(1→. The LPS showed a low level of toxicity, was not pyrogenic, and reduced the adhesiveness index of microorganisms to 2.12, which was twofold less than the control. LPS modified by complex compounds of germanium (IV) and tin (IV) were obtained. It was found that six LPS samples modified by Sn compounds and two LPS samples modified by Ge compounds lost their toxic activity when administered to mice in a dose of LD50 (105 µg/mice or 5 mg/kg). However, none of the modified LPS samples changed their serological activity in an Ouchterlony double immunodiffusion test in agar.


Assuntos
Lipídeo A/análogos & derivados , Antígenos O/química , Pantoea/química , Animais , Germânio/química , Dose Letal Mediana , Lipídeo A/toxicidade , Camundongos , Antígenos O/toxicidade , Compostos Organometálicos/química , Compostos Organometálicos/toxicidade , Estanho/química
4.
Carbohydr Res ; 489: 107932, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32035290

RESUMO

Two Pseudomonas strains were isolated from the strawberry leaves. The O-antigens were obtained using phenol-water method and mild acid degradation. The following structures of the O-polysaccharides were established by sugar analysis and 2D NMR spectroscopy: OPS of Pseudomonas koreensis BIM B-970G →3)-α-D-FucNAcp-(1 â†’ 2)-ß-D-Quip3NAc-(1 â†’ 3)-α-L-6dTalp4OAc-(1→ OPS of Pseudomonas oryzihabitans BIM B-1072G →4)-α-L-FucpNAm3OAc-(1 â†’ 3)-α-D-QuipNAc-(1 â†’ 4)-ß-D-GlcpNAc3NAcA-(1→ Where Am - acetimidoyl.


Assuntos
Fragaria/química , Folhas de Planta/química , Polissacarídeos/isolamento & purificação , Pseudomonas/química , Configuração de Carboidratos , Espectroscopia de Ressonância Magnética , Polissacarídeos/química
5.
Carbohydr Res ; 484: 107767, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400668

RESUMO

O-specific polysaccharide and lipid A were obtained from the lipopolysaccharide from new strain of Рantoea agglomerans P1a by mild acid hydrolysis. It was found that the major form of lipid A presented by tetraacylated derivative containing biphosphorylated GlcN disaccharide, three 14:0 (3-OH) and 12:0 residues. The structure of the O-specific polysaccharide was established by chemical, NMR and computational methods: →3)-α-D-Manp-(1 → 4)-ß-D-Fucp-(1 → 4)-ɑ-D-Fucp-(1→The LPS of Р. agglomerans P1a showed low level of toxicity and pyrogenicity to compare with LPS of E. coli O55:B5 and pyrogenal (respectively).


Assuntos
Lipídeo A/química , Antígenos O/química , Pantoea/química , Sequência de Carboidratos , Escherichia coli/química , Lipopolissacarídeos/química , Espectroscopia de Ressonância Magnética
6.
Front Microbiol ; 10: 1284, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293526

RESUMO

In skin, Cutibacterium acnes (former Propionibacterium acnes) can behave as an opportunistic pathogen, depending on the strain and environmental conditions. Acneic strains of C. acnes form biofilms inside skin-gland hollows, inducing inflammation and skin disorders. The essential exogenous products of C. acnes accumulate in the extracellular matrix of the biofilm, conferring essential bacterial functions to this structure. However, little is known about the actual composition of the biofilm matrix of C. acnes. Here, we developed a new technique for the extraction of the biofilm matrix of Gram-positive bacteria without the use of chemical or enzymatic digestion, known to be a source of artifacts. Our method is based on the physical separation of the cells and matrix of sonicated biofilms by ultracentrifugation through a CsCl gradient. Biofilms were grown on the surface of cellulose acetate filters, and the biomass was collected without contamination by the growth medium. The biofilm matrix of the acneic C. acnes RT5 strain appears to consist mainly of polysaccharides. The following is the ratio of the main matrix components: 62.6% polysaccharides, 9.6% proteins, 4.0% DNA, and 23.8% other compounds (porphyrins precursors and other). The chemical structure of the major polysaccharide was determined using a nuclear magnetic resonance technique, the formula being →6)-α-D-Galp-(1→4)-ß-D-ManpNAc3NAcA-(1→6)-α-D-Glcp-(1→4)-ß-D-ManpNAc3NAcA-(1→3)-ß-GalpNAc-(1→. We detected 447 proteins in the matrix, of which the most abundant were the chaperonin GroL, the elongation factors EF-Tu and EF-G, several enzymes of glycolysis, and proteins of unknown function. The matrix also contained more than 20 hydrolases of various substrata, pathogenicity factors, and many intracellular proteins and enzymes. We also performed surface-enhanced Raman spectroscopy analysis of the C. acnes RT5 matrix for the first time, providing the surface-enhanced Raman scattering (SERS) profiles of the C. acnes RT5 biofilm matrix and biofilm biomass. The difference between the matrix and biofilm biomass spectra showed successful matrix extraction rather than simply the presence of cell debris after sonication. These data show the complexity of the biofilm matrix composition and should be essential for the development of new anti-C. acnes biofilms and potential antibiofilm drugs.

7.
Carbohydr Res ; 472: 138-143, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30597450

RESUMO

Glycopolymers of two types were isolated from the cell wall of Lactobacillus rhamnosus BIM B-1039 by stepwise extraction with cold and hot 10% aq CCl3CO2H followed by anion-exchange gel chromatography. The following structures of the glycopolymers were established by sugar analysis, Smith degradation and 1D and 2D NMR spectroscopy.


Assuntos
Parede Celular/química , Lacticaseibacillus rhamnosus/química , Polissacarídeos Bacterianos/química , Sequência de Carboidratos , Cromatografia por Troca Iônica , Hidrólise , Ressonância Magnética Nuclear Biomolecular
8.
Carbohydr Res ; 465: 35-39, 2018 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-29929050

RESUMO

Strain of Pseudomonas psychrotolerans was cultured on the nutrient agar and in a liquid nutrient broth. Bacterial cells were phage-typed with bacteriophages specific to Pseudomonas. O-antigen was isolated from cells using phenol-water method and mild acid degradation. The following structures of the polysaccharides extracted were established by sugar analysis and 1D, 2D NMR spectroscopy: PSI→3)-α-D-Manp-(1→2)-α-D-Manp-(1→; PSII→3)-α-D-Rhap-(1→2)-ß-D-Rhap-(1→3)-α-D-Rhap-(1→; α-D-Glcp-(1Ë©; 2.


Assuntos
Polissacarídeos Bacterianos/química , Pseudomonas/química , Configuração de Carboidratos , Ressonância Magnética Nuclear Biomolecular
9.
Carbohydr Res ; 457: 8-13, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29304442

RESUMO

Two specific polysaccharides, together with an →4)-α-d-Glcp-(1→ glucan (bacterial glycogen), were obtained from a lipopolysaccharide preparation isolated from the bacterium Pseudomonas putida BIM B-1100 by phenol/water extraction. The following structures of the polysaccharides were established by composition analysis, Smith degradation, ESI-MS, and 1D and 2D NMR spectroscopy.


Assuntos
Lipopolissacarídeos/química , Antígenos O/química , Pseudomonas putida/química , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética
10.
Carbohydr Polym ; 181: 386-393, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29253987

RESUMO

Structurally related O-specific polysaccharide (O-antigen) and lipid A components were obtained by mild acid degradation of the lipopolysaccharides (LPSs) of two strains of bacteria Pantoea agglomerans, 7604 and 8674. Studies by sugar analysis along with 1D and 2D 1H and 13C NMR spectroscopy enabled elucidation of the following structures of the O-polysaccharides, which differ only in the linkage configuration of a side-chain glucose residue: R=α-d-Glcp in strain 7604 or ß-d-Glcp in strain 8674 Lipid A samples were studied by GC-MS and high-resolution ESI-MS and found to be represented by penta- and tetra-acyl species; lipid A of strain 8674 also included hexaacyl species. A peculiar feature of lipid A of both strains is the presence of the major cis-9-hexadecenoic (palmitoleic) acid, which has not been found in P. agglomerans strains studied earlier. The LPSs of both strains were pyrogenic, reduced the average adhesion and the index of adhesiveness and showed a relatively low level of lethal toxicity. O-antiserum against strain 7604 showed one-way cross-reactivity with the LPS of strain 8674, and O-antisera against both strains cross-reacted with LPSs of some other Р. agglomerans strains but more strains were serologically unrelated. These structural and serological data indicate immunochemical heterogeneity of Р. agglomerans strains and will find demand in classification of Р. agglomerans by O-antigens.


Assuntos
Lipopolissacarídeos/química , Lipopolissacarídeos/farmacologia , Antígenos O/química , Antígenos O/farmacologia , Pantoea/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Ácidos Graxos/análise , Soros Imunes/metabolismo , Lipídeo A/química , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
11.
Carbohydr Polym ; 165: 351-358, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28363559

RESUMO

Lipopolysaccharide (LPS) of Pantoea agglomerans 7969 isolated from apple tree was purified and characterized chemically by sugar and fatty acid analysis. Lipid A was analysed by negative-ion mode ESI MS and found to consist mainly of hexa- and tetra-acyl species typical of E. coli lipid A. The O-specific polysaccharide of the LPS was studied by sugar analysis, Smith degradation, and one- and two-dimensional 1H and 13C NMR spectroscopy. The polysaccharide is built up of linear tetrasaccharide repeating units, and about ∼25% repeats contain glycerol 1-phosphate on the GlcNAc residue: →3)-α-l-Rha p-(1→6)-α-d-Man p-(1→3)-α-d-Fuc p-(1→3)-ß-d-Glc pNAc-(1→∼25% Gro-1-P-(O→6)⌋ The LPS showed low levels of toxic and pyrogenic activities and reduced the average adhesion and the index of adhesiveness.


Assuntos
Lipopolissacarídeos/química , Pantoea/química , Sequência de Carboidratos , Escherichia coli , Espectroscopia de Ressonância Magnética , Malus/microbiologia , Antígenos O
12.
Carbohydr Res ; 433: 1-4, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27416015

RESUMO

O-specific polysaccharide was obtained from the lipopolysaccharide of Pseudomonas chlororaphis subsp. chlororaphis UCM B-106 and studied by composition analysis along with 1D and 2D (1)H and (13)C NMR spectroscopy. The polysaccharide was found to contain a derivative of pseudaminic acid (Pse) and the following structure of the trisaccharide repeating unit was established: →4)-ß-Psep5Ac7Hb-(2 â†’ 6)-ß-d-Galf-(1 â†’ 3)-ß-d-Galp-(1→ where Pse5Ac7Hb indicates 5-acetamido-3,5,7,9-tetradeoxy-7-[(R)-3-hydroxybutanoylamino]-l-glycero-l-manno-non-2-ulosonic acid.


Assuntos
Antígenos O/química , Pseudomonas chlororaphis/metabolismo , Sequência de Carboidratos , Espectroscopia de Ressonância Magnética , Polissacarídeos Bacterianos/química , Pseudomonas chlororaphis/química , Pseudomonas chlororaphis/imunologia
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