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1.
Bioorg Khim ; 41(2): 212-7, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26165128

RESUMEN

In order to develop new markers for immunofluorescence time-resolved luminescence analysis tetraketodiester carbazole series was obtained. Compound contains methoxycarbonyl reactive groups, separated from the 1,3-dicarbonyl chelating fragment by difluoromethylene spacers (CF2)4. Complexes of this compound with the ions Eu3+ are stable in aqueous solution and possess a long-living intensive luminescence with the main peaks: emission--in the area of 615 nm and excitation--in the 380-390 nm, that distinguishes them from most used analogues. Conjugate of streptavidin to compound was obtained and its fluorescent spectral characteristics allow to use it as a universal reagent for various schemes of biological microanalysis.


Asunto(s)
Carbazoles/química , Quelantes/química , Quelantes/síntesis química , Europio/química , Hidrocarburos Fluorados/química , Hidrocarburos Fluorados/síntesis química , Técnica del Anticuerpo Fluorescente Indirecta
2.
Antibiot Khimioter ; 55(11-12): 11-6, 2010.
Artículo en Ruso | MEDLINE | ID: mdl-21574419

RESUMEN

Beauveria feline No. 7 strain was isolated from the shrewmouse wool and characterized by production of a complex of destruxins cyclodepsipeptides. The strain was shown to produce significant quatities of destruxin B and pseudodestruxin C. The destruxins were found to be able to inhibit formation of biofilms by Pseudomonas aeruginosa ATCC 27833.


Asunto(s)
Beauveria/metabolismo , Depsipéptidos/biosíntesis , Pseudomonas aeruginosa/efectos de los fármacos , Musarañas/microbiología , Animales , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Beauveria/aislamiento & purificación , Biopelículas/efectos de los fármacos , Depsipéptidos/aislamiento & purificación , Depsipéptidos/farmacología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular
3.
Biochemistry (Mosc) ; 69(1): 103-7, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14972025

RESUMEN

For the first time in bacterial polysaccharides, residues of D- and L-aspartic acids were identified as N-acyl substituents of 4-amino-4,6-dideoxy-D-glucose in the O-antigens of enterobacteria of the genera Providencia and Proteus.


Asunto(s)
Ácido Aspártico/análisis , Ácido Aspártico/química , Antígenos O/química , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Estructura Molecular , Antígenos O/aislamiento & purificación , Proteus mirabilis/química
4.
Biochemistry (Mosc) ; 67(5): 558-65, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12059776

RESUMEN

The O-polysaccharide (OPS) was obtained from the lipopolysaccharide of Pseudomonas syringae pv. delphinii NCPPB 1879(T) and studied by sugar and methylation analyses, Smith degradation, and (1)H- and (13)C-NMR spectroscopy. The OPS was found to contain residues of L-rhamnose (L-Rha) and 3-acetamido-3,6-dideoxy-D-galactose (D-Fuc3NAc), and the following structure of the major (n = 2) and minor (n = 3) heptasaccharide repeating units of the OPS was established: [carbohydrate structure: see text]. The OPS is distinguished by the presence of oligosaccharide side chains consisting of three D-Fuc3NAc residues that are connected to each other by the (alpha 1-->2)-linkage. The OPS is characterized by a structural heterogeneity due to a different position of substitution of one of the four L-rhamnose residues in the main chain of the repeating unit as well as to the presence of oligosaccharide units with an incomplete side chain.


Asunto(s)
Galactosa/análogos & derivados , Galactosa/análisis , Antígenos O/química , Antígenos O/aislamiento & purificación , Pseudomonas/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Galactosa/química , Lipopolisacáridos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular
5.
Carbohydr Res ; 336(4): 329-36, 2001 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-11728403

RESUMEN

Studies by sugar and methylation analyses, Smith degradation, and 1H and 13C NMR spectroscopy revealed a structural heterogeneity in the O-polysaccharides of Pseudomonas syringae pvs. coronafaciens IMV 9030 and atrofaciens IMV 8281 owing to the presence of different types of repeating units. In strain IMV 9030, the major repeating units are a linear alpha-L-rhamnose trisaccharide and a tetrasaccharide (A, n=0 or 1). A minor repeating unit is a branched pentasaccharide with an alpha-L-rhamnose main chain and a lateral 3-acetamido-3,6-dideoxy-D-galactose (D-Fuc3NAc) residue (B, X=2, n=1). In strain IMV 8281, all repeating units are branched and differ in size and position of substitution of one of the alpha-L-rhamnose residues (tetrasaccharide, B, X=3, n=0; pentasaccharides, B, X=2 or 3, n=1). [structure--see text] Reinvestigation of the structure of the branched O-polysaccharide of P. syringae pv. tomato IPGR 140 showed that, together with the major tetrasaccharide repeating unit (B, X=3, n=0) [Knirel, Y. A., et al. Carbohydr. Res. 1993, 243, 199-204], it has a minor pentasaccharide repeating unit (B, X=3, n=1).


Asunto(s)
Lipopolisacáridos/química , Antígenos O/química , Pseudomonas/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Lipopolisacáridos/análisis , Datos de Secuencia Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Antígenos O/análisis , Ramnosa
6.
Carbohydr Res ; 333(4): 335-8, 2001 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-11454340

RESUMEN

The following structure of the O-specific polysaccharide of Citrobacter braakii O7a,3b,1c was established using sugar and methylation analyses and NMR spectroscopy, including 2D COSY, TOCSY, NOESY, and 1H, 13C heteronuclear single-quantum coherence (HSQC) experiments: (struture: see text). The main D-mannan chain of the polysaccharide studied has the same structure as the O-specific polysaccharide of Escherichia coli O9, Klebsiella pneumoniae O3, and Hafnia alvei PCM 1223.


Asunto(s)
Citrobacter/química , Antígenos O/química , Secuencia de Carbohidratos , Datos de Secuencia Molecular , Estructura Molecular , Monosacáridos/análisis , Resonancia Magnética Nuclear Biomolecular/métodos
7.
Carbohydr Res ; 331(3): 331-6, 2001 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-11383903

RESUMEN

A neutral O-specific polysaccharide was isolated from the lipopolysaccharide of Citrobacter gillenii strain PCM 1544, representing serotype O12a,12b. The polysaccharide was studied by sugar and methylation analyses and Smith degradation along with 1H and 13C NMR spectroscopy, including a ROESY experiment. The following structure of the tetrasaccharide repeating unit was established, in which substitution with terminal GlcNAc is approximately 60%. [structure: see text]


Asunto(s)
Citrobacter/química , Lipopolisacáridos/química , Antígenos O/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Carbohidratos/análisis , Metilación , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular/métodos , Antígenos O/aislamiento & purificación , Serotipificación
8.
FEMS Immunol Med Microbiol ; 30(3): 223-7, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11335142

RESUMEN

On the basis of chemical and methylation analyses, one- and two-dimensional (1)H- and (13)C-NMR spectroscopy, including COSY, TOCSY, NOESY and (1)H, (13)C HSQC experiments, a neutral O-specific polysaccharide isolated from Hafnia alvei strain PCM 1223 lipopolysaccharide (LPS) was found to be an alpha-mannan composed of pentasaccharide repeating units having the following structure:-->3)-alpha-D-Manp-(1-->3)-alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->2)-alpha-D-Manp-(1-->. Immunoblotting showed a strong cross-reactivity between anti-H. alvei PCM 1223 serum and LPSs of Escherichia coli O9 and Klebsiella pneumoniae O3. The serological relationship of the LPSs of these bacteria is due to the structural identity of their O-specific polysaccharides, though the LPSs differ in their core regions.


Asunto(s)
Hafnia alvei/química , Antígenos O/inmunología , Cromatografía de Gases , Escherichia coli/química , Escherichia coli/inmunología , Hafnia alvei/genética , Immunoblotting , Klebsiella pneumoniae/química , Klebsiella pneumoniae/inmunología , Espectroscopía de Resonancia Magnética , Mananos , Antígenos O/química , Antígenos O/aislamiento & purificación , Serología
9.
Carbohydr Res ; 331(2): 219-24, 2001 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-11322737

RESUMEN

A lipopolysaccharide (LPS) was isolated by hot phenol-water extraction from Helicobacter pylori strain D4 and found to contain no fucosylated poly-N-acetyllactosamine chain typical of most H. pylori strains studied but a homopolymer of D-glycero-D-manno-heptose (DD-Hep). The heptan attached to a core oligosaccharide was released by mild acid degradation of the LPS, and the following structure of the trisaccharide-repeating unit was established by chemical methods and 1H and 13C NMR spectroscopy: --> 2)-D-alpha-D-Hepp-(1 --> 3)-D-alpha-D-Hepp-(1 --> 3)-D-alpha-D-Hepp-(1 -->. 1H NMR spectroscopy performed on small amounts of the intact LPS revealed the presence of the same polysaccharide in LPS of H. pylori strains D2 and D5, but not strain D10.


Asunto(s)
Helicobacter pylori/química , Heptosas/química , Lipopolisacáridos/química , Espectroscopía de Resonancia Magnética
10.
Carbohydr Res ; 330(4): 505-10, 2001 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-11269402

RESUMEN

The O-methylation pattern of the O polysaccharide (OPS) of the lipopolysaccharide of Pseudomonas syringae pv. phaseolicola GSPB 1552 was revealed by methylation (CD3I) analysis, Smith degradation, and NMR spectroscopy. Together with the major O repeats consisting of D-rhamnopyranose (D-Rhap) and D-fucofuranose (D-Fucf), there are minor repeats (approximately 30%) containing 3-O-methyl-D-rhamnose (D-acofriose), which is 2-substituted in the interior repeats and occupies the terminal non-reducing end of the OPS. It was suggested that the methylated O repeats are linked to each other nearby the non-reducing end of the OPS and that the 'biological' O repeat of the OPS has the following structure: [molecular structure: see text].


Asunto(s)
Manosa/análogos & derivados , Antígenos O/química , Pseudomonas/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Manosa/química , Metilación , Datos de Secuencia Molecular , Peso Molecular , Resonancia Magnética Nuclear Biomolecular , Ramnosa/química
11.
Carbohydr Res ; 330(4): 523-8, 2001 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-11269405

RESUMEN

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-->.


Asunto(s)
Hafnia alvei/química , Polisacáridos Bacterianos/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Cromatografía de Gases y Espectrometría de Masas , Hafnia alvei/inmunología , Metilación , Datos de Secuencia Molecular , Peso Molecular , Resonancia Magnética Nuclear Biomolecular
12.
Carbohydr Res ; 330(1): 83-92, 2001 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-11217966

RESUMEN

The O-specific polysaccharide (OPS) of Vibrio cholerae 08 was isolated by mild acid degradation of the lipopolysaccharide and studied by two-dimensional NMR spectroscopy, including NOESY and heteronuclear multiple-bond correlation (HMBC) experiments. The OPS was found to have a tetrasaccharide repeating unit with the following structure: --> 4)-beta-D-Glcp NAc3NAcylAN-(1 --> 4)-beta-D-Manp NAc3NAcAN-(1 --> 4)-alpha-L-Gulp NAc3NAcA-(1 --> 3) -beta-D-QuipNAc4NAc-(1 --> where QuiNAc4NAc is 2,4-diacetamido-2,4,6-trideoxyglucose, GlcNAc3NAcylAN is 2-acetamido-3-(N-formyl-L-alanyl)amino-2,3-dideoxyglucuronamide, ManNAc3NAcAN is 2,3-diacetamido-2,3-dideoxymannuronamide, and GulNAc3NAcA is 2,3-diacetamido-2,3-dideoxyguluronic acid. The OPS was stable towards acid hydrolysis and solvolysis with anhydrous hydrogen fluoride, but could be cleaved selectively with trifluoromethanesulfonic (triflic) acid by the glycosidic linkages of beta-QuiNAc4NAc and alpha-GulNAc3NAcA. The structures of the oligosaccharides obtained that were elucidated by electrospray ionization (ESI) MS and NMR spectroscopy, confirmed the OPS structure.


Asunto(s)
Antígenos O/química , Vibrio cholerae/inmunología , Antígenos Bacterianos/química , Antígenos Bacterianos/aislamiento & purificación , Conformación de Carbohidratos , Secuencia de Carbohidratos , Mesilatos , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular/métodos , Antígenos O/aislamiento & purificación , Polisacáridos Bacterianos/inmunología , Solventes , Espectrometría de Masa por Ionización de Electrospray
13.
Carbohydr Res ; 329(2): 453-7, 2000 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-11117329

RESUMEN

The structure of a neutral polysaccharide isolated by degradation with dilute acetic acid of the lipopolysaccharide (LPS) of P. mirabilis O24 has been determined recently [E. Literacka et al., FEBS Lett., 456 (1999) 227-231]. Further studies of this LPS using alkaline degradation and hydrolysis at pH 4.5 showed that the polysaccharide chain includes an acetal-linked pyruvic acid residue, which is removed completely during delipidation with acetic acid. A revision using 1H and 13C NMR spectroscopy and methylation analysis resulted in determination of the following full structure of the repeating unit of the O-specific polysaccharide: carbohydrate sequence [see text] where D-Gal3,4(S-Pyr) is 3,4-O-[(S)-1-carboxyethylidene]-D-galactose.


Asunto(s)
Antígenos O/química , Polisacáridos Bacterianos/química , Proteus mirabilis/química , Ácido Acético/farmacología , Secuencia de Carbohidratos , Concentración de Iones de Hidrógeno , Hidrólisis , Espectroscopía de Resonancia Magnética , Metilación , Datos de Secuencia Molecular , Antígenos O/aislamiento & purificación , Proteus mirabilis/clasificación , Ácido Pirúvico/análisis , Serotipificación
14.
FEBS Lett ; 456(2): 227-31, 1999 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-10456314

RESUMEN

Strains of Proteus mirabilis belonging to serogroups O24 and O29 are frequent in clinical specimens. Anti-P. mirabilis O24 serum cross-reacted with the lipopolysaccharide (LPS) of P. mirabilis O29 and vice versa. The structures of the O-specific polysaccharides (OPSs, O-antigens) of both LPSs were established using sugar analysis and one- and two-dimensional 1H- and 13C-NMR spectroscopy and found to be different. SDS-PAGE and Western immunoblotting suggested that the serological cross-reactivity of the LPSs is due to a common epitope(s) on the core-lipid A moiety, rather than on the OPS. Therefore, the epitope specificity and the structures of the O-antigens studied are unique among Proteus serogroups.


Asunto(s)
Antígenos O/química , Proteus mirabilis/química , Proteus mirabilis/inmunología , Anticuerpos Antibacterianos/sangre , Conformación de Carbohidratos , Secuencia de Carbohidratos , Reacciones Cruzadas , Epítopos/química , Humanos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Infecciones por Proteus/inmunología , Proteus mirabilis/clasificación , Serotipificación
15.
Biochemistry (Mosc) ; 64(5): 523-7, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10381612

RESUMEN

A neutral polysaccharide containing D-galactose, 2-acetamido-2-deoxy-D-glucose, and 3-acetamido-3,6-dideoxy-D-glucose (Qui3NAc) in the ratios 2:1:1 was obtained by mild acid degradation of lipopolysaccharide of the bacterium Providencia alcalifaciens O5 followed by gel chromatography and ion-exchange chromatography or treatment with anhydrous hydrogen fluoride. On the basis of full acid hydrolysis, methylation, and 1H- and 13C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), total correlation spectroscopy (TOCSY), H-detected heteronuclear 1H,13C single-quantum coherence (HSQC), and nuclear Overhauser effect spectroscopy (NOESY), the following structure of the linear tetrasaccharide repeating unit of the polysaccharide was established:


Asunto(s)
Antígenos O/química , Providencia/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular
16.
Carbohydr Res ; 306(1-2): 331-3, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9691457

RESUMEN

The following structure of the O-specific polysaccharide of Citrobacter freundii O3a,3b,1c containing D-mannose and D-rhamnose was established using sugar analysis and NMR spectroscopy, including computer-assisted analysis of the 13C NMR spectrum, 2D COSY, H,H-relayed COSY, heteronuclear 13C, 1H correlation (HETCOR), and rotating-frame NOE spectroscopy (ROESY):-->4)-alpha-D-Manp-(1-->3)-beta-D-Rhap-(1-->4) -beta-D-Rhap-(1-->.


Asunto(s)
Citrobacter freundii/química , Antígenos O/química , Secuencia de Carbohidratos , Citrobacter freundii/inmunología , Espectroscopía de Resonancia Magnética , Manosa/análisis , Datos de Secuencia Molecular , Antígenos O/aislamiento & purificación , Ramnosa/análisis
17.
Eur J Biochem ; 254(1): 58-62, 1998 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-9652394

RESUMEN

The O-specific polysaccharide of Vibrio cholerae 0155 was studied by sugar and methylation analyses, dephosphorylation with 48% hydrofluoric acid, 1H- and 13C-NMR spectroscopy, including two-dimensional COSY, TOCSY, NOESY, and heteronuclear single-quantum coherence (HSQC) experiments. The following structure of the pentasaccharide repeating unit of the polysaccharide was established: carbohydrate sequence [see text]. An unusual component, D-galactose 4,6-cyclophosphate, has been reported previously as a component of the capsular polysaccharide and O-antigen of V. cholerae O139 Bengal and appears to be responsible for the known serological cross-reactivity between V. cholerae O139 and O155.


Asunto(s)
Galactosafosfatos/química , Antígenos O/química , Polisacáridos Bacterianos/química , Vibrio cholerae/inmunología , Conformación de Carbohidratos , Secuencia de Carbohidratos , Reacciones Cruzadas/inmunología , Epítopos/química , Epítopos/inmunología , Lipopolisacáridos/química , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Oligosacáridos/química , Análisis de Secuencia , Serología
18.
Eur J Biochem ; 251(3): 980-5, 1998 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9490075

RESUMEN

On the basis of chemical analyses and NMR spectroscopic studies, it was found that the O-specific polysaccharide (O-PS) isolated from the Hafnia alvei PCM 1199 lipopolysaccharide (LPS) is a glycerol teichoic-acid-like polymer having a repeating unit of the following structure: [structure in text] where Qui4NAc is 4-acetamido-4,6-dideoxyglucose and O-acetylation at both positions is non-stoichiometric. The glycosidic linkage of the lateral beta-D-GlcpNAc residue is acid-labile and cleaved from the O-PS during mild acid hydrolysis or dephosphorylation with 48% hydrofluoric acid. Comparative analysis revealed that the structure of the H. alvei PCM 1199 O-PS is similar to that of H. alvei PCM 1205, which differs in the presence of an additional lateral alpha-D-Glcp residue and the position of one of the O-acetyl groups only. Accordingly, serological tests revealed a high degree of serological similarity between LPSs and O-PSs of the two H. alvei strains.


Asunto(s)
Enterobacteriaceae/química , Antígenos O/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Carbohidratos/análisis , Enterobacteriaceae/inmunología , Metilación , Datos de Secuencia Molecular , Antígenos O/aislamiento & purificación , Especificidad de la Especie , Ácidos Teicoicos/química
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