Publications by authors named "Raisa P Gorshkova"

13 Publications

  • Page 1 of 1

Against the rules: a marine bacterium, Loktanella rosea, possesses a unique lipopolysaccharide.

Glycobiology 2010 May 21;20(5):586-93. Epub 2010 Jan 21.

Dipartimento di Chimica Organica e Biochimica, Università di Napoli "Federico II", Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy.

Bacteria are an inimitable source of new glyco-structures potentially useful in medicinal and environmental chemistry. Lipopolysaccharides (LPS; endotoxins) are the major components of the outer membrane of Gram-negative bacteria; being exposed toward the external environment they can undergo structural changes and thus, they often possess peculiar chemical features that allow them to thrive in harsh chemical and physical environments. Marine bacteria have evolved and adapted over millions of years in order to succeed in different environments, finding a niche for their survival characterized by severe physical or chemical parameters. The present work focuses on the structural investigation of the LPS from Loktanella rosea, a marine Gram-negative bacterium. Through chemical analysis, 2D nuclear magnetic resonance and matrix-assisted laser desorption ionization mass spectrometry investigations, a unique LPS carbohydrate backbone has been defined. The lipid A skeleton consists of a trisaccharide backbone lacking the typical phosphate groups and is characterized by two beta-glucosamines and an alpha-galacturonic acid. The core region is built up of three ulosonic acids, with two 3-deoxy-d-manno-oct-2-ulopyranosonic acid residues, one of which is carrying a neuraminic acid. This carbohydrate structure is an exceptional variation from the typical architectural skeleton of endotoxins which consequently implies a very different biosynthesis.
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http://dx.doi.org/10.1093/glycob/cwq008DOI Listing
May 2010

The O-chain structure from the LPS of marine halophilic bacterium Pseudoalteromonas carrageenovora-type strain IAM 12662T.

Carbohydr Res 2005 Dec 29;340(17):2693-7. Epub 2005 Sep 29.

Dipartimento di Chimica Organica e Biochimica, Università di Napoli Federico II, via Cintia 4, 80126 Napoli, Italy.

The O-chain polysaccharide of the lipopolysaccharide from the halophilic marine bacterium Pseudoalteromonas carrageenovora IAM 12662T was characterized. The structure was studied by means of chemical analysis and 2D NMR spectroscopy of the de-O-acylated lipopolysaccharide and shown to be the following:Col is colitose, 3,6-di-deoxy-L-xylo-hexose.
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http://dx.doi.org/10.1016/j.carres.2005.09.007DOI Listing
December 2005

Structural characterization of the carbohydrate backbone of the lipooligosaccharide of the marine bacterium Arenibacter certesii strain KMM 3941(T).

Carbohydr Res 2005 Nov 5;340(16):2540-9. Epub 2005 Oct 5.

Dipartimento di Chimica Organica e Biochimica, Università di Napoli Federico II, via Cintia 4, 80126 Napoli, Italy.

The structure of the carbohydrate backbone of the lipooligosaccharide (LOS) of the marine bacterium Arenibacter certesii strain KMM 3941(T) has been elucidated. The structure was obtained by means of compositional analysis, matrix-assisted laser desorption/ionization mass spectrometry and complete 1H and 13C and 31P NMR spectroscopy. It shows novel and interesting aspects and is the first description of Arenibacter lipopolysaccharides. Strong and mild alkaline treatments, to fully deacylate and only to O-deacylate the LOS were performed in order to determine the core structure. The core consists of a mixture of species differing by the presence of a non-stoichiometric alpha-d-rhamnose residue. The Kdo unit is substituted at O-5 by alpha-mannose and at O-4 by a alpha-galactosyluronic acid phosphate. The lipid A is constituted by a bis-phosphorylated disaccharide unit composed by a 2,3-diamino-2,3-dideoxy-beta-d-glucopyranose (DAG) residue as non-reducing end and a GlcN as reducing end.
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http://dx.doi.org/10.1016/j.carres.2005.08.021DOI Listing
November 2005

The structure of the O-polysaccharide of the Pseudoalteromonas rubra ATCC 29570T lipopolysaccharide containing a keto sugar.

Carbohydr Res 2005 Oct;340(15):2369-75

Department of Chemistry, National University of Ireland, Galway, Ireland.

The structure of the phenol-soluble polysaccharide from Pseudoalteromonas rubra type strain ATCC 29570T has been elucidated using 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, gNOESY, ROESY, 1H,13C gHMQC and gHMBC experiments. It is concluded that the trisaccharide repeating unit of the polysaccharide has the following structure: [carbohydrate structure: see text] where Sug is 2-acetamido-2,6-dideoxy-D-xylo-hexos-4-ulose, Am is acetimidoyl and Acyl is a malic acid residue, which is O-acetylated in approximately 70% of the units.
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http://dx.doi.org/10.1016/j.carres.2005.07.007DOI Listing
October 2005

Structure of an acidic polysaccharide from the marine bacterium Pseudoalteromonas aliena type strain KMM 3562T containing two residues of L-serine in the repeating unit.

Carbohydr Res 2005 Jun;340(8):1483-7

Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, Sweden.

The structure of an acidic polysaccharide from Pseudoalteromonas aliena type strain KMM 3562(T) has been elucidated. The polysaccharide was studied by component analysis, (1)H and (13)C NMR spectroscopy, including 2D NMR experiments. A (1)H, (13)C band-selective constant-time heteronuclear multiple-bond connectivity experiment was used to determine amide linkages, between serine and uronic acid (UA) residues, via (3)J(H,C) correlations between Ser-alphaH and UA-C-6. It was found that the polysaccharide consists of pentasaccharide repeating units with the following structure: [carbohydrate structure]; see text.
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http://dx.doi.org/10.1016/j.carres.2005.03.013DOI Listing
June 2005

Structure of the O-specific polysaccharide from Shewanella japonica type strain KMM 3299T containing the rare amino sugar Fuc4NAc.

Carbohydr Res 2005 Jun;340(8):1557-61

Department of Chemistry, National University of Ireland, Galway.

An acidic O-specific polysaccharide (PS) of the agar-digesting bacterium Shewanella japonica with the type strain KMM 3299(T) was obtained by mild acid hydrolysis of the lipopolysaccharide. The polysaccharide was studied by component analysis, methylation analysis, (1)H and (13)C NMR spectroscopy, including 2D NMR experiments. The PS was determined to have the following structure involving three unusual amino sugars:
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http://dx.doi.org/10.1016/j.carres.2005.01.040DOI Listing
June 2005

The complete structure of the core carbohydrate backbone from the LPS of marine halophilic bacterium Pseudoalteromonas carrageenovora type strain IAM 12662T.

Carbohydr Res 2005 Jun;340(8):1475-82

Dipartimento di Chimica Organica e Biochimica, Università di Napoli Federico II, Italy.

The complete novel structure of the components of the core oligosaccharide fraction from the LOS of the halophilic marine bacterium Pseudoalteromonas carrageenovora was characterized. The fully de-acylated lipooligosaccharide was studied by means of compositional analysis, matrix-assisted laser desorption/ionization mass spectrometry and complete (1)H and (13)C and (31)P NMR spectroscopy. The core oligosaccharide is composed by a mixture of species differing for the length of the sugar chain and the phosphorylation pattern: [carbohydrate structure]; see text. All sugars are D-pyranoses. Hep is L-glycero-D-manno-heptose, Kdo is 3-deoxy-D-manno-oct-2-ulosonic acid, P is phosphate, residues and substituents in italic are not stoichiometrically linked.
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http://dx.doi.org/10.1016/j.carres.2005.03.012DOI Listing
June 2005

Structure of an acidic polysaccharide from the agar-decomposing marine bacterium Pseudoalteromonas atlantica strain IAM 14165 containing 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno-non-2-ulosonic acid.

Carbohydr Res 2005 Jan;340(1):69-74

Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden.

The structure of an acidic polysaccharide from Pseudoalteromonas atlantica strain 14165 containing 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno-non-2-ulosonic acid (di-N-acetylpseudaminic acid, Pse5Ac7Ac) has been elucidated. The polysaccharide was studied by 1H and 13C NMR spectroscopy, including 2D experiments, along with sugar and methylation analyses. After a selective hydrolysis a modified polysaccharide devoid of its side chain could be isolated. It was found that the polysaccharide has pentasaccharide repeating units with following structure: [structure: see text].
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http://dx.doi.org/10.1016/j.carres.2004.11.007DOI Listing
January 2005

The complete structure of the lipooligosaccharide from the halophilic bacterium Pseudoalteromonas issachenkonii KMM 3549T.

Carbohydr Res 2004 Aug;339(11):1985-93

Dipartimento di Chimica Organica e Biochimica, Università di Napoli Federico II, via Cintia 4, 80126 Napoli, Italy.

Novel lipooligosaccharide components were isolated and identified from the lipooligosaccharide fraction of the halophilic marine bacterium Pseudoalteromonas issachenkonii type strain KMM 3549T. The complete structure was achieved by chemical analysis, 2D NMR spectroscopy and MALDI mass spectrometry as the following: [carbohydrate formula see text] All sugars are d-pyranoses. Hep is L-glycero-D-manno-heptose, Kdo is 3-deoxy-D-manno-oct-2-ulosonic acid, P is phosphate, residues and substituents in italic are not stoichiometrically linked. In addition, by MALDI mass spectrometry of the intact LOS, the lipid A moiety was also identified as a mixture of penta-, tetra- and triacylated species.
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http://dx.doi.org/10.1016/j.carres.2004.05.008DOI Listing
August 2004

Structure of an acidic O-specific polysaccharide from marine bacterium Shewanella fidelis KMM 3582T containing Nepsilon-[(S)-1-carboxyethyl]-Nalpha-(D-galacturonoyl)-L-lysine.

Carbohydr Res 2004 Jun;339(9):1655-61

Department of Chemistry, National University of Ireland, Galway, Ireland.

The O-specific polysaccharide was isolated by mild acid degradation of the lipopolysaccharide of the marine bacterium Shewanella fidelis type strain KMM 3582T and studied by sugar analysis along with 1H and 13C NMR spectroscopy including one-dimensional NOE in difference mode and two-dimensional experiments. The polysaccharide was found to consist of linear tetrasaccharide repeating units containing Nepsilon-[(S)-1-carboxyethyl]-Nalpha-(D-galacturonoyl)-L-lysine and having the following structure: [See text.] The amide of D-galacturonic acid with Nepsilon-[(S)-1-carboxyethyl]-L-lysine ('alaninolysine', 2S,8S-AlaLys) was found for the first time in nature as a component of the O-specific polysaccharide of Providencia rustigianii O14 (Carbohydr. Res. 2003, 338, 1009-1016).
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http://dx.doi.org/10.1016/j.carres.2004.04.003DOI Listing
June 2004

Structures of polysaccharides and oligosaccharides of some Gram-negative marine Proteobacteria.

Carbohydr Res 2003 Nov;338(23):2449-57

Pacific Institute of Bioorganic Chemistry, Far East Branch of the Russian Academy of Sciences, Vladivostok 690022, Russian Federation.

The chemical structures of polysaccharides and LPS core oligosaccharides, isolated from various Gram-negative marine bacteria from the genera Pseudoalteromonas and Shewanella belonging to the Alteromonadaceae family and gamma-subclass of Proteobacteria, are reviewed. The polysaccharides are distinguished by the acidic character (e.g., due to the presence of hexuronic and aldulosonic acids and their derivatives) and the occurrence of unusual sugars, including N-acyl derivatives of 6-deoxyamino sugars, such as N-acetyl-D-quinovosamine, N-acetyl-L-fucosamine and N-acetyl-6-deoxy-L-talosamine, and higher sugars like 2,6-dideoxy-2-acetamido-4-C-(3'-carboxamide-2',2'-dihydroxypropyl)-D-galactopyranose (shewanellose). Many constituent sugars have various uncommon non-sugar substituents, such as alanine, formic, lactic and hydroxybutyric acids, sulfate, phosphate, and 2-aminopropane-1,3-diol.
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http://dx.doi.org/10.1016/j.carres.2003.06.004DOI Listing
November 2003

Structure of an acidic polysaccharide from the marine bacterium Pseudoalteromonas flavipulchra NCIMB 2033(T).

Carbohydr Res 2003 Feb;338(5):459-62

Department of Chemistry, National University of Ireland, University Road, Galway, Ireland.

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-->.
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http://dx.doi.org/10.1016/s0008-6215(02)00483-4DOI Listing
February 2003

Structure of the phenol-soluble polysaccharide from Shewanella putrefaciens strain A6.

Carbohydr Res 2002 Jun;337(12):1119-27

Arrhenius Laboratory, Department of Organic Chemistry, Stockholm University, Sweden.

The structure of the phenol-soluble polysaccharide from Shewanella putrefaciens strain A6 has been elucidated. Chemical modifications of the polymer in conjunction with 1H and 13C NMR spectroscopy, including 2D techniques, were employed in the analysis. It is concluded that the repeating unit is composed of two nine-carbon sugars as follows: -->4)-alpha-NonpA-(2-->3)-beta-Sugp-(1--> where alpha-NonpA is 5-acetamido-7-acetamidino-8-O-acetyl-3,5,7,9-tetradeoxy-L-glycero-alpha-D-galacto-non-2-ulosonic acid (8eLeg) and beta-Sugp is 2-acetamido-2,6-dideoxy-4-C-(3'-carboxamide-2',2'-dihydroxypropyl)-beta-D-galactopyranose, with the proposed name Shewanellose (She).
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http://dx.doi.org/10.1016/s0008-6215(02)00101-5DOI Listing
June 2002