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The structure of the K141 type capsular polysaccharide (CPS) produced by Acinetobacter baumannii KZ1106, a clinical isolate recovered from Kazakhstan in 2016, was established by sugar analyses and one- and two-dimensional 1H and 13C NMR spectroscopy. The CPS was shown to consist of branched tetrasaccharide repeating units (K-units) with the following structure: [Display omitted] This structure was found to be consistent with the genetic content of the KL141 CPS biosynthesis gene cluster at the chromosomal K locus in the KZ1106 whole genome sequence. Assignment of the encoded enzymes allowed the first sugar of the K unit to be identified, which revealed that the β-d-Glc p NAc-(1→3)-d-Glc p NAc bond is the linkage between K-units formed by the Wzy KL141 polymerase. [Display omitted] • Complete structure of Acinetobacter baumannii K141 CPS solved. • Annotations for the KL141 gene cluster reported. • Genetic content of KL141 is consistent with the structure reported. [ABSTRACT FROM AUTHOR]

K63 capsular polysaccharide produced by Acinetobacter baumannii isolate LUH5551 (previously designated isolate O24) was re-examined using sugar analysis, Smith degradation, and one- and two-dimensional 1H and 13C NMR spectroscopy. Though previously reported as O24 consisting of linear tetrasaccharide units that include a 7-acetamido-5-acylamino form of 8-epilegionaminic acid [8eLeg5R7Ac, acylated at C5 with (S)-3-hydroxybutanoyl or acetyl (1:1)], the elucidated structure of the K63 type capsule was found to include a derivative of 5,7-diamino-3,5,7,9-tetradeoxy- d - glycero - d - galacto -non-2-ulosonic (legionaminic) acid, Leg5Ac7R, where R is either (S)-3-hydroxybutanoyl or an acetyl group (∼1:1 ratio). This finding is consistent with the presence of the lgaABCHIFG gene module for Leg5Ac7R biosynthesis in the KL63 gene cluster at the capsular polysaccharide (CPS) biosynthesis K locus in the LUH5551 genome. The glycosyltransferases (Gtrs) and Wzy polymerase encoded by KL63 were assigned to linkages in the linear K63 tetrasaccharide unit and linkage of the K63 units. [Display omitted] • The structure of the A. baumannii K63 capsule has been determined. • This structure revises that reported for O24. • K63 includes 5,7-diamino-3,5,7,9-tetradeoxy- d - glycero - d - galacto -non-2-ulosonic acid. • Roles for the glycosyltransferases and Wzy polymerase encoded by KL63 are assigned. [ABSTRACT FROM AUTHOR]

Mild acid degradation of the lipopolysaccharide of Yersinia kristensenii C-134 afforded a glycerol teichoic acid-like O-polysaccharide, which was studied by sugar analysis, O-deacetylation and dephosphorylation along with 1D and 2D NMR spectroscopy. The following structure of the O-polysaccharide was established: This structure is related to those of other Y. kristensenii O-polysaccharides studied earlier. The O-antigen gene cluster of Y. kristensenii С-134 was analyzed and found to be consistent with the O-polysaccharide structure established. Image 1 • Structure of the O-polysaccharide of Yersinia kristensenii C-134 was established. • The O-polysaccharide has a glycerol teichoic acid-like structure. • Dephosphorylation of the O-polysaccharide afforded a glycerol-linked hexasaccharide. • The O-antigen gene cluster was found to be consistent with the O-polysaccharide structure. [ABSTRACT FROM AUTHOR]

A 3,6-dideoxy- l - xylo -hexose (colitose)-containing partially O-acetylated branched polysaccharide was obtained by mild acid hydrolysis (2% HOAc, 100 °C, 2 h) of the lipopolysaccharide of Escherichia albertii HK18069 followed by gel-permeation chromatography on Sephadex G-50 Superfine. Part of colitose residues (~40%) was cleaved upon hydrolysis, and the full cleavage was achieved by prolonged hydrolysis (8 h) under the same conditions and resulted in a modified linear polysaccharide. Structure of the O-polysaccharide of E. albertii HK18069 was established by 1D and 2D 1H and 13C NMR spectroscopy applied to both initial and modified O-deacetylated and colitose-free polysaccharides: Image 2 where β- d -Gal p is mono-O-acetylated at position either 3 (~50%) or 4 (~30%). The O-antigen gene cluster of E. albertii HK18069 between conserved galF and gnd genes together with flanking regions was sequenced, and predicted functions of the genes were found to be consistent with the O-polysaccharide structure established. The O-polysaccharide structure and the O-antigen gene cluster of E. albertii HK18069 are related to those of Esherichia coli O55 and E. coli O128 reported earlier. It is proposed to create for strain HK18069 a new E. albertii O-serogroup, O8. Image 1 • A colitose-containing O-polysaccharide is harbored by E. albertii HK18069 (serotype O8). • Structure of the O-polysaccharide was established by sugar analysis and NMR spectroscopy. • O-antigen gene cluster of E. albertii HK18069 was sequenced and the genes were annotated. • Predicted gene functions are consistent with the O-polysaccharide established. • O-antigen structures and gene clusters of E. albertii O8 and E. coli O55 and O128 are related. [ABSTRACT FROM AUTHOR]

O-specific polysaccharide was obtained by mild acid hydrolysis of the lipopolysaccharide of plant-growth-promoting rhizobacteria Azospirillum doebereinerae GSF71T and studied by sugar analysis along with 1H and 13C NMR spectroscopy, including 2D 1H,1H COSY, TOCSY, ROESY, 1H,13C HSQC, and HMBC experiments. It was established that the polysaccharide is linear and consists of tetrasaccharide repeating units with the following structure: Image 1 • OPS was isolated from Azospirillum doebereinerae GSF71T lipopolysaccharide. • Structure of the OPS was established by chemical analyses and NMR spectroscopy. • The OPS is built up of linear tetrasaccharide repeating units. • The OPS contains fully O-acetylated Rha and partially O-acetylated GlcNAc. [ABSTRACT FROM AUTHOR]

Abstract Halomonas ventosae RU5S2EL, a halophilic Gram-negative bacterium isolated from salt sediments of lake Elton (Russia), was cultivated and the lipopolysaccharide was extracted by the Westphal procedure. The O-specific polysaccharide (OPS) was obtained by mild acid hydrolysis of the lipopolysaccharide and was studied by sugar analysis along with 1H and 13C NMR spectroscopy, including 1H,1H COSY, TOCSY, ROESY, 1H,13C HSQC, and HMBC experiments as well as Smith degradation. The OPS was found to consist of branched pentasaccharide repeating units of the following structure: Image 2 Graphical abstract Image 1 Highlights • The OPS was isolated from Halomonas ventosae RU5S2EL lipopolysaccharide. • The structure of the OPS was established by chemical analyses and NMR spectroscopy. • The OPS is built up of branched pentasaccharide repeating units. • The O-unit contains four Rha residues in the main chain and a terminal Glc. [ABSTRACT FROM AUTHOR]

O-specific polysaccharide was obtained by mild acid hydrolysis of the lipopolysaccharide of nitrogen-fixing bacterium Azospirillum fermentarium CC-LY743 T (IBPPM 578) and was studied by sugar analysis along with 1 H and 13 C NMR spectroscopy, including 1 H, 1 H COSY, TOCSY, ROESY, and 1 H, 13 C HSQC and HMBC experiments. The polysaccharide was found to be linear and to consist of alterating α- l -fucose and α- d -mannose residues in tetrasaccharide repeating units of the following structure: →2)-α-D-Man p -(1 → 3)-α-L-Fuc p -(1 → 3)-α-D-Man p -(1 → 3)-α-L-Fuc p -(1→ [ABSTRACT FROM AUTHOR]

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)-β-D-Rhap-(1→3)-α-D-Rhap-(1→; α-D-Glcp-(1˩; 2 [ABSTRACT FROM AUTHOR]

Mild acid hydrolysis of the lipopolysaccharide of Escherichia coli O54 afforded an O-polysaccharide, which was studied by sugar analysis, solvolysis with anhydrous trifluoroacetic acid, and 1 H and 13 C NMR spectroscopy. Solvolysis cleaved predominantly the linkage of β- d -Rib f and, to a lesser extent, that of β- d -Glc p NAc, whereas the other linkages, including the linkage of α- l -Rha p, were stable under selected conditions (40 °C, 5 h). The following structure of the O-polysaccharide was established: →4)-α- d -Gal p A-(1 → 2)-α- l -Rha p -(1 → 2)-β- d -Rib f -(1 → 4)-β- d -Gal p -(1 → 3)-β- d -Glc p NAc-(1→ The O-antigen gene cluster of E. coli O54 was analyzed and found to be consistent in general with the O-polysaccharide structure established but there were two exceptions: i) in the cluster, there were genes for phosphoserine phosphatase and serine transferase, which have no apparent role in the O-polysaccharide synthesis, and ii) no ribofuranosyltransferase gene was present in the cluster. Both uncommon features are shared by some other enteric bacteria. [ABSTRACT FROM AUTHOR]

The O-specific polysaccharide (O-antigen) is a part of the lipopolysaccharide on the cell surface of Gram-negative bacteria. The O-polysaccharide was obtained by mild acid hydrolysis of the lipopolysaccharide of Escherichia coli O27 and studied by sugar analysis and Smith degradation along with 1 H and 13 C NMR spectroscopy. The following structure of the branched hexasaccharide repeating unit was established, which is unique among known structures of bacterial polysaccharides: Image 2 where GlcA is non-stoichiometrically O-acetylated at position 3 (∼22%) or 4 (∼37%). Functions of genes in the O-antigen gene cluster of E. coli O27 were tentatively assigned by comparison with sequences in the available databases and found to be consistent with the O-polysaccharide structure. [ABSTRACT FROM AUTHOR]

Dihydroresveratrol cellobioside and xylobioside, whose structures were designed based on that of the naturally occurring melanogenesis-controlling agent dihydroresveratrol glucoside, were synthesized via Schmidt glycosylation as the key step. Both analogues stimulated melanogenesis with efficacies comparable to that of 8-methoxypsoralen, a well-known melanogenesis activator. This suggests that diglycosyl modification of the 4’-OH on the dihydroresveratrol skeleton leads to the activation of melanogenesis, both with and without hydroxymethyl groups in the sugar moieties. [ABSTRACT FROM AUTHOR]

Mild alkaline degradation of the lipopolysaccharide of Escherichia coli O80 afforded a polysaccharide, which was studied by sugar analysis, selective cleavage of glycosidic linkages, and 1 H and 13 C NMR spectroscopy. Solvolysis of the polysaccharide with CF 3 CO 2 H cleaved the linkages of α-Fuc and β-linked GlcNAc and GalNAc residues to give two disaccharides. The following structure of the hexasaccharide repeating unit of the O-polysaccharide was established: The polysaccharide repeat also contains a minor O-acetyl group but its position was not determined. The O-antigen gene cluster of E. coli O80 between the conserved galF and gnd genes was analyzed and found to be consistent with the O-polysaccharide structure established. [ABSTRACT FROM AUTHOR]

The lipopolysaccharide of Escherichia coli O156 was degraded under mild acidic and alkaline conditions and the resulting polysaccharides were studied by sugar analysis and 1 H and 13 C NMR spectroscopy. The following structure of the pentasaccharide repeating unit of the O-polysaccharide was established: where R pyr indicates R -configurated pyruvic acid acetal. Minor O-acetyl groups also were present and tentatively localized on the Gal residues. The gene cluster for biosynthesis of the O-antigen of E. coli O156 was analyzed and shown to be consistent with the O-polysaccharide structure. [ABSTRACT FROM AUTHOR]

The O-polysaccharide was isolated by mild acid degradation of the lipopolysaccharide of Enterobacter cloacae G3421 and studied by sugar analysis along with 1D and 2D 1 H and 13 C NMR spectroscopy. In addition, partial solvolysis with anhydrous trifluoroacetic acid was applied, which cleaved selectively the α- l -rhamnopyranosidic linkages. The following structure of the branched hexasaccharide repeating unit was established. The O-polysaccharide studied shares the β- l -Rha p -(1→4)-α- l -Rha p -(1→2)-α- l -Rha p trisaccharide fragment with the O-polysaccharide of Shigella boydii type 18. The O-antigen gene cluster of E. cloacae G3421 was sequenced. Functions of genes in the cluster, including those for glycosyltransferases, were tentatively assigned by a comparison with sequences in the available databases and found to be consistent with the O-polysaccharide structure. [ABSTRACT FROM AUTHOR]

Mild acid degradation of the lipopolysaccharide of Escherichia coli O96 afforded a mixture of two polysaccharides. The following structure of the pentasaccharide repeating unit of the major polymer was established by sugar analysis, Smith degradation, and 1 H and 13 C NMR spectroscopy: The O-antigen gene cluster of E. coli O96 between conserved galF and gnd genes was found to be consistent with this structure, and hence, the major polysaccharide represents the O96-antigen. The O96-antigen structure and gene cluster are similar to those of E. coli O170, and two proteins encoded in the gene clusters of both bacteria were putatively assigned a function of galactofuranosyltransferases. The minor polymer has the same structure as a peptidoglycan-related polysaccharide reported earlier in Providencia alcalifeciens O45 and several other O-serogoups of this species (Ovchinnikova OG, Liu B, Kocharova NA, Shashkov AS, Kondakova AN, Siwinska M, Feng L, Rozalski A, Wang L, Knirel YA. Biochemistry (Moscow) 2012; 77 :609-15) →4)-β- d -Glc p NAc-(1→4)-β- d -Glc p NAc3( R lac- l Ala)-(1→ where R lac- l Ala indicates ( R )-1-[( S )-1-carboxyethylaminocarbonyl]ethyl. [ABSTRACT FROM AUTHOR]

Mild acid hydrolysis of the lipopolysaccharide of Escherichia coli O57 afforded an O-polysaccharide, which was isolated by gel permeation chromatography (GPC) and studied by sugar analysis, Smith degradation and solvolysis with trifluoroacetic acid, along with 2D 1 H and 13 C NMR spectroscopy. The O-polysaccharide was found to contain d -Glc, d -Gal, d -GalA, d -GlcNAc, and l -FucNAc, as well as O-acetyl groups. Smith degradation of the O-deacetylated polysaccharide destroyed side-branch β-Glс p and α-Gal p A to give a modified linear polysaccharide. Solvolysis cleaved selectively the linkage of α- l -Fuc p NAc to give a pentasaccharide corresponding to the O-polysaccharide repeat. A comparison of the NMR spectra of the initial and O-deacetylated polysaccharides showed that α-Gal p A is non-stoichiometrically O-acetylated at position either 2 (∼30%) or 3 (∼40%). The following structure of the O-polysaccharide was established, which is unique among known bacterial polysaccharide structures: Image 2 [ABSTRACT FROM AUTHOR]

The O-polysaccharide (OPS) was isolated by mild acid degradation of the lipopolysaccharide of Enterobacter cloacae G2559 and studied by sugar analysis along with 1D and 2D 1H and 13C NMR spectroscopy. The following structure of the branched pentasaccharide repeating unit was established. [Display omitted] The O-antigen gene cluster of Enterobacter cloacae G2559 was sequenced. The gene functions were tentatively assigned by comparison with sequences in the available databases and found to be in full agreement with the O-antigen structure. [Display omitted] • E. cloacae is the important multi-drug resistant bacteria. • The O-specific polysaccharide structure of E. cloacae G2559 was established. • New OPS is consists of a number of pentasaccharide repeating O-units. • The O-antigen gene cluster of E. cloacae G2559 was sequenced and annotated. [ABSTRACT FROM AUTHOR]

On mild acid degradation of the lipopolysaccharide of Escherichia coli O160, the O-polysaccharide was cleaved by acid-labile glycosyl phosphate linkages in the main chain. The resultant oligosaccharide and the alkali-treated lipopolysaccharide were studied by sugar analysis along with 1 H and 13 C NMR spectroscopies, and the following structure of the branched pentasaccharide repeating unit of the O-polysaccharide was established: The O-antigen gene cluster of E. coli O160 was found to be consistent with the O-polysaccharide structure established. [ABSTRACT FROM AUTHOR]

The O-polysaccharide (O-antigen) of Escherichia coli O43 was isolated from the lipopolysaccharide and studied by chemical methods, including sugar analyses, Smith degradation, and solvolysis with anhydrous trifluoroacetic acid, along with 1 H and 13 C NMR spectroscopy. The following structure of the pentasaccharide repeating unit of the O-polysaccharide was established: Functions of genes in the O-antigen gene cluster of E. coli O43 were assigned by a comparison with sequences in the available databases and found to be in agreement with the O-polysaccharide structure. [ABSTRACT FROM AUTHOR]

The O-polysaccharide (O-antigen) of Escherichia coli O169 was studied by sugar analysis along with 1D and 2D 1 H and 13 C NMR spectroscopy. The following structure of the branched hexasaccharide repeating unit was established: The O-polysaccharide of E. coli O169 differs from that of Shigella boydii type 6 only in the presence of a side-chain glucose residue. A comparison of the O-antigen biosynthesis gene clusters between the galF to gnd genes in the genomes of the two bacteria revealed their close relationship. The glycosyltransferase gene responsible for the formation of the β- d -Glc p -(1→6)-α- d -Gal p linkage in the O-antigen was identified in the gene cluster. [ABSTRACT FROM AUTHOR]

Capsular polysaccharide (CPS) was isolated from Acinetobacter baumannii NIPH146, and the following structure of branched pentasaccharide repeating unit was established by sugar analyses along with 1D and 2D NMR spectroscopy: In comparison to most other known capsular polysaccharides of A. baumannii , the CPS studied is neutral and lacks any specific monosaccharide component. The synthesis, assembly and export of this structure could be attributed to genes in a novel capsule biosynthesis gene cluster, designated KL37, which was found in the NIPH146 genome. The CPS of A. baumannii NIPH146 shares the α- d -Gal p -(1→6)-β- d -Glc p -(1→3)- d -Gal p NAc-(1→ trisaccharide fragment with the CPS units of several A. baumannii strains, including ATCC 17978 and LUH 5537 that carry the KL3 and KL22 gene clusters, respectively. KL37 contains two genes for glycosyltransferases that are related to two glycosyltransferase genes present in both KL3 and KL22, and the encoded proteins could be tentatively assigned to linkages between sugars in the CPS repeat. [ABSTRACT FROM AUTHOR]

The following structure of the O-polysaccharide of Escherichia coli HS1/2 serving as a primary receptor for bacteriophage DT57-12 was elucidated by sugar analysis along with 1D and 2D 1 H and 13 C NMR spectroscopy: This structure is shared by E. coli O87 type strain. Putatively assigned functions of genes in the O-antigen gene cluster of E. coli O87 are consistent with the O-polysaccharide structure established. [ABSTRACT FROM AUTHOR]

An acidic O-polysaccharide (O-antigen) was isolated from the lipopolysaccharide of Escherichia coli O140 and studied by sugar analysis along with 1D and 2D 1 H and 13 C NMR spectroscopy. The following structure of the branched hexasaccharide repeating unit was established: The O-antigen gene cluster of E. coli O140 was sequenced. The gene functions were tentatively assigned by a comparison with sequences in the available databases and found to be in full agreement with the E. coli O140 polysaccharide structure. [ABSTRACT FROM AUTHOR]

Uridine 5′-diphosphate-glucuronic acid (UDP-GlcA) and UDP-galacturonic acid (UDP-GalA), the unique carboxylic acid-formed sugar nucleotides, are key precursors involved in the biosynthesis of numerous cell components. Limited availability of those components has been hindering the development of efficient ways towards facile synthesis of bioactive glycans such as glycosaminoglycans. In current study, we biochemically characterized two UDP-sugar pyrophosphorylases from Arabidopsis thaliana (AtUSP) and Bifidobacterium infantis ATCC15697 (BiUSP), and compared their activities towards a panel of sugar-1-phosphates and derivatives. Both enzymes showed significant pyrophosphorylation activities towards GlcA-1-phosphate, and AtUSP also exhibited comparable activity towards GalA-1-phosphate. By combining with monosaccharide-1-phosphate kinases, we have developed an efficient and facile one-pot three-enzyme approach to quickly obtain hundreds milligrams of UDP-GlcA and UDP-GalA. [ABSTRACT FROM AUTHOR]

Structure of the O-specific polysaccharide from Pseudomonas chlororaphis subsp. aureofaciens UCM B-306 was elucidated by sugar analysis along with 1D and 2D 1 H and 13 C NMR spectroscopy. The polysaccharide is built up of trisaccharide repeats containing d -rhamnose, 2,4-diacetamido-2,4,6-trideoxy- d -glucose ( d -QuiNAc4NAc), and 2-acetamido-2-deoxy- d -galacturonic acid ( d -GalNAcA), which is amidated in ∼40% repeats. It was suggested that the O-polysaccharide has a blockwise structure, which can be presented as follows: -[→3)-α- d -Rha p -(1→4)-α- d -Gal p NAcA-(1→3)-α- d -Qui p NAc4NAc-(1-] n → and -[→3)-α- d -Rha p -(1→4)-α- d -Gal p NAcAN-(1→3)-α- d -Qui p NAc4NAc-(1-] m →, where GalNAcAN indicates 2-acetamido-2-deoxy- d -galacturonamide, n: m =∼3:2. [ABSTRACT FROM AUTHOR]

For the functional analysis of mucin related glycan, we synthesized core 3 and 5 structures of mucin type O -glycan and investigated their binding interaction with lectins using sugar chip technology. The construction of Tn antigen moiety containing α- N -acetylgalactosamine residue was achieved by α-selective glycosylation of 2-azido-6- tert -butyldiphenylsilyl-3,4-di-O-chloroacetyl-2-deoxy-galctopyranosyl imidate and glucose moiety, which acts as a hydrophilic spacer when immobilized on a gold-coated sensor chip. Core 3 and core 5 structures were synthesized by the glycosylation of appropriate N -acetylglucosamine and N -galactosamine donors, respectively, and were converted into sugar-chain ligand conjugates according to the method reported. The interaction analysis of lectins with sugar chips coated with ligand conjugates was performed with a surface plasmon resonance (SPR) biosensor. The specific interaction was observed between the core 3 structure and Jacalin (JAC) and kinetic parameters were estimated as k a = 1.5 × 104, k d = 5.8 × 10−3, and K D = 3.8 × 10−7. [Display omitted] • Newly designed GalNAc building block for α-glycosylation. • Efficiently sythesized core 3 and 5 ligand conjugates. • Investigated the interaction of core 3 and 5 structure with specific lectins using SPR. [ABSTRACT FROM AUTHOR]

Abstract: The O-polysaccharide (O-antigen) of Escherichia coli O154 was studied by sugar analysis along with 1D and 2D 1H and 13C NMR spectroscopy. The following structure of the branched pentasaccharide repeating unit was established: Display Omitted The O-antigen gene cluster of E. coli O154 was sequenced. The gene functions were tentatively assigned by comparison with sequences in the available databases and found to be in full agreement with the O-polysaccharide structure. [Copyright &y& Elsevier]

Abstract: The O-polysaccharide (O-antigen) of Escherichia coli O102 was studied by sugar analysis along with one- and two-dimensional 1H and 13C NMR spectroscopy. The following structure of the branched pentasaccharide repeating unit was established: Display Omitted The O-antigen gene cluster of E. coli O102 was sequenced. The gene functions were tentatively assigned by comparison with sequences in the available databases and found to be in full agreement with the E. coli O102 O-polysaccharide structure. [Copyright &y& Elsevier]

Abstract: The acidic O-polysaccharide (O-antigen) of Escherichia coli O120 was isolated from the lipopolysaccharide and studied by sugar analysis and NMR spectroscopy. The following structure of the branched hexasaccharide repeating unit was established, which is unique among the known structures of bacterial polysaccharides: ▪ The O-antigen gene cluster of E. coli O120 was sequenced. The gene functions were tentatively assigned by comparison with sequences in the available databases and found to be in full agreement with the O-polysaccharide structure. [Copyright &y& Elsevier]

Abstract: The following structure of the O-specific polysaccharide (O-antigen) of Budvicia aquatica 20186 was elucidated by sugar analysis along with 1D and 2D 1H and 13C NMR spectroscopy: →4)-α-l-Rhap-(1→3)-α-d-Galp-(1→2)-α-Yerp-(1→3)-β-d-GalpNAc-(1→ where Yer stands for 3,6-dideoxy-4-C-[(S)-1-hydroxyethyl]-d-xylo-hexose (yersiniose A). [Copyright &y& Elsevier]

Abstract: The acidic O-polysaccharide (O-antigen) of Escherichia coli O41 was studied by sugar analysis along with 1D and 2D 1H and 13C NMR spectroscopy, and the following structure of the branched hexasaccharide repeating unit was established: ▪ This structure is unique among the known structures of bacterial polysaccharides. The O-antigen gene cluster of E. coli O41 was sequenced. The gene functions were tentatively assigned by a comparison with sequences in the available databases and found to be in full agreement with the E. coli O41 O-polysaccharide structure. [Copyright &y& Elsevier]

Abstract: The O-polysaccharide (O-antigen) of Escherichia coli O19ab was studied by sugar analysis along with 1D and 2D 1H and 13C NMR spectroscopy. The following structure of the linear pentasaccharide repeating unit was established: where the degree of O-acetylation of GlcNAc is ∼33%. The O-antigen gene cluster of E. coli O19ab was sequenced. The gene functions were tentatively assigned by comparison with sequences in the available databases and found to be in full agreement with the E. coli O19ab-antigen structure. [Copyright &y& Elsevier]

Abstract: A water-soluble glucan, isolated from the alkaline extract of the fruit bodies of an edible mushroom, Lentinus squarrosulus (Mont.) Singer was found to consist of (1→3,6)-linked, (1→3)-linked, (1→6)-linked, and terminal β-d-glucopyranosyl moieties in a relative proportion of approximately 1:2:1:1. This polysaccharide showed optimum activation of macrophages as well as splenocytes and thymocytes at 10μg/mL. Structural investigation was carried out using sugar analysis, methylation analysis, periodate oxidation study, and NMR experiments (1H, 13C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC). On the basis of above-mentioned experiments, the structure of the repeating unit of the polysaccharide was established as:▪ [Copyright &y& Elsevier]

Abstract: The O-polysaccharides were isolated from the lipopolysaccharides of emerging human pathogens Photorhabdus asymbiotica subsp. asymbiotica US-86 and US-87 and subsp. australis AU36, AU46, and AU92. Studies by sugar analysis and 1H and 13C NMR spectroscopy before and after O-deacetylation showed that the O-polysaccharide structures are essentially identical within, and only slightly different between, the subspecies. The following structures of the repeating units of the O-polysaccharides were established: →3)-β-d-Quip4NGlyFo-(1→4)-α-d-GalpNAcAN3Ac-(1→4)-α-d-GalpNAcA3R-(1→3)-α-d-QuipNAc-(1→ where GalNAcA stands for 2-acetamido-2-deoxygalacturonic acid, GalNAcAN for amide of GalNAcA, QuiNAc for 2-acetamido-2,6-dideoxyglucose, and Qui4NGlyFo for 4,6-dideoxy-4-(N-formylglycyl)aminoglucose; R=Ac in subsp. asymbiotica or H in subsp. australis. The structures established resemble those of a number of taxonomically remote bacteria including Francisella tularensis (Vinogradov, E. V.; Shashkov, A. S.; Knirel, Y. A.; Kochetkov, N. K.; Tochtamysheva, N. V.; Averin, S. P.; Goncharova, O. V.; Khlebnikov, V. S. Carbohydr. Res. 1991, 214, 289–297), which differs in (i) the presence of a formyl group on Qui4N rather than the N-formylglycyl group, (ii) the mode of the linkage between the repeating units (β1→2 vs α1→3), (iii) amidation of both GalNAcA residues rather than one residue, and iv) the lack of O-acetylation. [Copyright &y& Elsevier]

Abstract: Cronobacter sakazakii G2706 and G2704 are the reference strains of serotypes O5 and O6 in the serological classification of this species proposed recently. Mild acid degradation of the lipopolysaccharides of both strains resulted in cleavage of the O-polysaccharide chains at the acid-labile linkage of 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) to yield oligosaccharides representing repeating units of the O-polysaccharides. The oligosaccharides and alkali-degraded lipopolysaccharides were studied by sugar analysis along with 1D and 2D 1H and 13C NMR spectroscopy, and the following O-polysaccharide structures were established:▪ The structure of strain G2706 is unique among the known bacterial polysaccharide structures, whereas that of strain G2704 is identical to the structure of Cronobacter malonaticus 3267 [MacLean, L. L.; Vinogradov, E.; Pagotto, F.; Farber, J. M.; Perry, M. B. Biochem. Cell Biol. 2009, 87, 927–932], except for that the latter lacks O-acetylation. Putative functions of the genes in the O-antigen gene clusters of C. sakazakii strains studied are in agreement with the O-polysaccharide structures. [Copyright &y& Elsevier]

Abstract: The O-specific polysaccharide from the lipopolysaccharide of Cronobacter sakazakii G2592 was studied by sugar analysis along with 1D and 2D 1H and 13C NMR spectroscopy, and the following structure of the pentasaccharide repeating unit was established: ▪ This structure is unique among the known bacterial polysaccharide structures, which is in accord with classification of strain G2592 into a new C. sakazakii serotype, O7. It is in agreement with the O-antigen gene cluster of this strain, which was found between the housekeeping genes JUMPStart and gnd and characterized by sequencing and tentative assignment of the gene functions. [Copyright &y& Elsevier]

Abstract: An immunoenhancing polysaccharide isolated from the aqueous extract of the fruit bodies of the mushroom, Pleurotus florida blue variant, was found to consist of d-glucose and d-galactose in a molar ratio of nearly 5:1. On the basis of sugar analysis, methylation analysis, periodate oxidation, Smith degradation, and NMR studies (1H, 13C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC), the structure of the repeating unit of the polysaccharide was established as: Display Omitted The molecule activated macrophages, splenocytes, and thymocytes. [ABSTRACT FROM AUTHOR]

Abstract: The O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O12. Its structure was studied by sugar analysis using GLC of the alditol acetates and (S)-2-octyl glycosides, methylation analysis, Smith degradation, and 1H and 13C NMR spectroscopy, including 2D 1H–1H COSY, TOCSY, ROESY, 1H–13C HSQC, and HMBC experiments. It was found that the polymer is a neutral heteropolysaccharide and has a branched heptasaccharide repeating unit with the following structure:▪ [Copyright &y& Elsevier]

The O-polysaccharide (OPS) was isolated by mild acid degradation of the lipopolysaccharide of Enterobacter cloacae G3422 and studied by chemical methods, including sugar analyses, Smith degradation, and solvolysis with anhydrous trifluoroacetic acid, along with 1H and 13C NMR spectroscopy. The following structure of the branched tetrasaccharide repeating unit was established: [Display omitted] The O-antigen gene cluster of Enterobacter cloacae G3422 was sequenced. The gene functions were tentatively assigned by comparison with sequences in the available databases and found to be in a good agreement with the O-antigen structure. [Display omitted] • E. cloacae is the important multi-drug resistant bacteria. • The O-specific polysaccharide structure of E. cloacae G3222 was established. • The OPS was found to contain 6-deoxy-talose. • The O-antigen gene cluster of E. cloacae G3222 was sequenced and annotated. [ABSTRACT FROM AUTHOR]

K87 capsular polysaccharide (CPS) was isolated from Acinetobacter baumannii isolate LUH5547 that carries the KL87 capsule biosynthesis gene cluster at the chromosomal K locus. Studies by sugar analysis, selective chemical cleavages, and 1D and 2D 1H and 13C NMR spectroscopy showed that the CPS has a branched heptasaccharide repeat (K unit) containing one residue each of d -glucose (d -Glс p), d -glucuronic acid (d -Glс p A), N -acetyl- d -glucosamine (d -Glс p NAc), 6-deoxy- l -talose (l -6dTal p), and three residues of l -rhamnose (l -Rha p). The following structure of the CPS was established: → 3) − α - L - R ha p − (1 → 2) - α - L - R h a p - (1 → 3) - α - L - 6 d T a l p - (1 → 3) - β - D - G l c p N A c - (1 → 2 ↑ 1 β - D - G l c p A - (4 ← 1) - α - D - G l c p (2 ← 1) - α - L - R h a p The position of a minor O-acetyl group present in the CPS was not determined. Functions of enzymes coded by genes in the KL87 gene cluster were tentatively assigned and found to be consistent with the CPS structure. [Display omitted] • Capsule structure from A. baumannii LUH5547 correlates with K locus genes. • Structure belongs to a group of 6-deoxy- l -talose containing capsules from A. baumannii. • The linkage cleaved by a bacteriophage depolymerase was identified. [ABSTRACT FROM AUTHOR]

The O-antigen (O-polysaccharide) is an essential component of lipopolysaccharide on the surface of Gram-negative bacteria and plays an important role in interaction with host organisms. In this study, we investigated the chemical structure and characterized the gene cluster of Enterobacter cloacae K7 O-antigen. As judged by sugar analyses along with NMR spectroscopy data, E. cloacae K7 antigen has a tetrasaccharide O-unit with the following structure: →8)-β-Pse p 5Ac7Ac-(2 → 2)-β- l -Rha p -(1 → 4)-α- l -Rha p -(1 → 3)-α- d -Gal p -(1→ The O-antigen gene cluster of E. cloacae K7 between conserved genes galF and gnd was sequenced. Most genes necessary for the O-antigen synthesis were found in the cluster and their functions were tentatively assigned by comparison with sequences in the available databases. [Display omitted] • Bacterium E. cloacae is highly spread in nature. • Early rhizosphere strain E. cloacae K7 isolated from Jerusalem artichoke. • The O-specific polysaccharide structure of E. cloacae K7 was established. • The OPS was found to contain rarely occurred nonulosonic acid. • The O-antigen gene cluster of E. cloacae K7 was sequenced and annotated. [ABSTRACT FROM AUTHOR]

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-. Image 1 • Two Pseudomonas strains were isolated from Ficus elastica leaves. • Both O-polysaccharides contain Rha and Glc residues. • P. psychrotolerans BIM B-1171G is not sensitive to the studied collection strains of bacteriophages. • Pseudomonas sp. BIM B-1172 G was complete sensitive to most phages tested. [ABSTRACT FROM AUTHOR]

The O-polysaccharide (O-antigen) of Escherichia coli SDLZB008 was isolated from the lipopolysaccharide and studied by sugar analyses along with 1H and 13C NMR spectroscopy. The following structure of the branched pentasaccharide repeating unit was established, which is unique among the known structures of bacterial polysaccharides: Image 2 The O-antigen gene cluster of E. coli SDLZB008 has been sequenced. The gene functions were tentatively assigned by comparison with sequences in the available databases and found to be in full agreement with the O-polysaccharide structure. Image 1 • Strain SDLZB008 is a new strain of E. coli. • The OPS structure of E. coli SDLZB008 was established. • The OPS was found to contain d -Fuc p 3NAc residue. • The O-antigen gene cluster of E. coli SDLZB008 was sequenced and annotated. [ABSTRACT FROM AUTHOR]

The structure of the O-polysaccharide of an aerobic halophilic bacterium Salinicola salarius HO-14 isolated from a heavy oil reservoir with highly mineralized water was determined. The neutral O-polysaccharide of strain HO-14 was isolated from the lipopolysaccharide and studied by sugar analysis and NMR spectroscopy. The linear tetrasaccharide repeating unit was found to have the following structure: →2)-α- l -Rha p -(1 → 3)-β- l -Rha p -(1 → 2)-α- l -Rha p- (1 → 2)-α- d -Man p- (1→ Image 1 • Salinicola salarius strain HO-14 was isolated from the heavy oil deposit. • The OPS structure of S. salarius HO-14 was established. • The OPS is built up from linear tetrasaccharide repeating O-units. • Structure of the OPS is unique among known bacterial polysaccharides. [ABSTRACT FROM AUTHOR]

The lipopolysaccharide was obtained from the cells of Azospirillum formosense CC-Nfb-7(T), a diazotrophic bacterium isolated from agricultural soil. The O-specific polysaccharide (OPS) was released by mild acid hydrolysis of the lipopolysaccharide and was studied by sugar analysis along with 1H and 13C NMR spectroscopy, including 1H,1H COSY, TOCSY, ROESY, 1H,13C HSQC, and HMBC experiments, and Smith degradation. The following structure of partially methylated OPS composed of trisaccharide repeating units was established: Image 1 • O-polysaccharide (OPS) was isolated from the A. formosense lipopolysaccharide. • The OPS was studied by chemical methods and1D and 2D NMR spectroscopy. • The OPS contained l -fucose, d -xylose and partially 3-O-methylated d -mannose. • Structure of branched trisaccharide repeating units of the OPS was established. [ABSTRACT FROM AUTHOR]

Two polysaccharide fractions were obtained by mild acid degradation of the lipopolysaccharide of the marine bacterium Marinicella litoralis KMM 3900T. The major polysaccharide was found to contain glycerol 1-phosphate (PGro) and methyl phosphate substituents (PMe), and the following structure of its disaccharide repeating unit was established by sugar analysis, dephosphorylation, Smith degradation, and 1D and 2D NMR spectroscopy: →4)-α-L-Rha p 2PGro(~40%)-(1 → 3)-β-D-Man p 6PMe(~80%)-(1 →. The minor polysaccharide was shown to consist of 4- O -sulfate- d -mannopyranosyl residues, non-stoichiometric methylated at O-3 and acetylated at O-6: →2)-α-D-Man p 3R4S6Ac(~75%)-(1→, where R is Me (85%) or H (15%). Image 1 • Structures of two polysaccharides from M. litoralis KMM 3900T were established. • Major PS-1 was found to contain glycerol 1-phosphate and methyl phosphate substituents. • Minor PS-2 was found to be a methylated and sulfated α-D-mannan. [ABSTRACT FROM AUTHOR]

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-FucNAc p -(1 → 2)-β-D-Qui p 3NAc-(1 → 3)-α-L-6dTal p 4OAc-(1→ OPS of Pseudomonas oryzihabitans BIM B-1072G →4)-α-L-Fuc p NAm3OAc-(1 → 3)-α-D-Qui p NAc-(1 → 4)-β-D-Glc p NAc3NAcA-(1→ Where Am – acetimidoyl. Image 1 • Pseudomonas koriensis and P. oryzihabitans were isolated from strawberry leaves. • Structures of the O-repeats of isolated strains were established. • Both O-polysaccharides have trisaccharide O-repeat. • Both O-polysaccharides are O-acetylated (6dTal p 4OAc or Fuc p NAm3OAc). [ABSTRACT FROM AUTHOR]

P. mirabilis strains Kro 45 and Kwy 46 were isolated from the pus and the muscular fluid, respectively, of a hospitalized 61-year-old female in Łódź, Poland. Both strains demonstrated a good swarming ability on a solid medium, and the Dienes test for differentiation of swarming strains indicated their identity. The strains were serologically identical and did not belong to any of the known Proteus O1-O81 serogroups. In this work, we studied the O-specific polysaccharide (O antigen) of P. mirabilis Kwy46, which defines the immunospecificity of the strain. The O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide, and the following structure of its oligosaccharide repeat (O-unit) was established by sugar analysis along with 1D and 2D 1H and 13C NMR spectroscopy: Image 2 where (S)-lac indicates an (S)-1-carboxyethyl group [an (S)-lactic acid residue], which forms an ether with a GlcNAc residue (so called glycolactilic acid). This structure is unique among Proteus O-polysaccharides but shares a trisaccharide fragment with that of P. mirabilis O5. Studies of the cross-reactivity between P. mirabilis Kwy 46 O antiserum/lipopolysaccharide and Proteus O1-O81 lipopolysaccharides/O antisera allowed identification of a putative Kwy 46 O-antigen epitope. Based on the data obtained, it is proposed to create a new O82 serogroup within the genus Proteus represented by the studied P. mirabilis isolates. Image 1 • Proteus mirabilis strain Kwy 46 represents a newly created Proteus O82 serogroup. • The Kwy 46 O antigen contains an ether of GlсNAc with (S)-lactic acid. • Serological cross-reactivity was observed for P. mirabilis O82 and P. mirabilis O5. • A common fragment in the O antigens is likely responsible for the cross-reactivity. [ABSTRACT FROM AUTHOR]

The structure of the K128 capsular polysaccharide (CPS) produced by Acinetobacter baumannii isolate KZ-1093 from Kazakhstan was established by sugar analysis and Smith degradation along with 1D and 2D 1H and 13C NMR spectroscopy. The CPS was found to consist of branched pentasaccharide repeating units containing only neutral sugars, and its composition and topology are closely related to those of the A. baumannii K116 CPS. The K128 and K116 oligosaccharide units differ in the linkage between the disaccharide side chain and the main chain, with a β-(1 → 6) linkage in K128 replacing a β-(1 → 4) linkage in K116. The linkages between the repeating units in the K128 and K116 CPSs are also different, with K128 units linked by β- d -Gal p NAc-(1 → 4)- d -Gal p, and β- d -Gal p NAc-(1 → 3)- d -Gal p linkages between K116 units. The KZ-1093 genome was sequenced and the CPS biosynthesis gene cluster at the chromosomal K locus was designated KL128. Consistent with the CPS structures, KL128 differs from KL116 in one glycosyltransferase gene and the gene for the Wzy polymerase. In KL128, the gtr200 glycosyltransferase gene replaces gtr76 in KL116, and Gtr200 was therefore assigned to the different β- d -Gal p NAc-(1 → 6)- d -Gal p linkage in K128. Similarly, the Wzy K128 polymerase could be assigned to the β- d -Gal p NAc-(1 → 4)- d -Gal p linkage between the K128 units. Image 1 • The Acinetobacter baumannii K128 capsule structure is closely related to the K116 capsule structure. • The function of the glycosyltransferases, Wzy polymerases and initiating transferase were unambiguously assigned. • The KL128 gene cluster includes genes for glycosyltransferases and simple sugar synthesis. [ABSTRACT FROM AUTHOR]

A novel strain of Lactobacillus mucosae was isolated from a faecal sample of an individual who had adhered to a strict vegetarian diet for nine years. The strain displayed a ropy character when grown on plates and generated a relatively small amount (62 mg/L) of an exopolysaccharide (EPS) when grown in broth culture. The EPS eluted from a size exclusion chromatography column as a single band with a weight average molecular mass of 1.51 × 104 g/mol. Monomer analysis and sugar absolute configuration analysis confirmed that the EPS was a D-galactan. Using linkage analysis in combination with 1D and 2D-NMR spectroscopy, with spectra being recorded for both the native EPS and for the products generated by Smith degradation of the EPS, the following structure was determined for the repeat unit of the polysaccharide: Image 1 This is a novel D-galactan and represents the first structure for an EPS produced by a strain of Lactobacillus mucosae to be reported. Image 1 • Isolation of a novel, potentially probiotic, strain of L. mucosae (L mucosae VG1). • Production and isolation of an exopolysaccharide from L mucosae VG1. • Characterization of the exopolysaccharide from L mucosae VG1; a novel D-galactan. [ABSTRACT FROM AUTHOR]