Lipopolysaccharide of the Complex.

Lipopolysaccharide (LPS), localized in the outer leaflet of the outer membrane, serves as the major surface component of the Gram-negative bacterial cell envelope responsible for the activation of the host's innate immune system. Variations of the LPS structure utilized by Gram-negative bacteria promote survival by providing resistance to components of the innate immune system and preventing recognition by TLR4. This review summarizes studies of the biosynthesis of Yersinia pseudotuberculosis complex LPSs, and the roles of their structural components in molecular mechanisms of yersiniae pathogenesis and immunogenesis.

Hypoacylated LPS from Foodborne Pathogen Induces Moderate TLR4-Mediated Inflammatory Response in Murine Macrophages.

Toll-like receptor 4 (TLR4) initiates immune response against Gram-negative bacteria upon specific recognition of lipid A moiety of lipopolysaccharide (LPS), the major component of their cell wall. Some natural differences between LPS variants in their ability to interact with TLR4 may lead to either insufficient activation that may not prevent bacterial growth, or excessive activation which may lead to septic shock. In this study we evaluated the biological activity of LPS isolated from pathogenic strain of , the most widespread bacterial cause of foodborne diarrhea in humans.

Full structure and insight into the gene cluster of the O-specific polysaccharide of Yersinia intermedia H9-36/83 (O:17).

Lipopolysaccharide was isolated from bacteria Yersinia intermedia H9-36/83 (O:17) and degraded with mild acid to give an O-specific polysaccharide, which was isolated by GPC on Sephadex G-50 and studied by sugar analysis and 1D and 2D NMR spectroscopy. The polysaccharide was found to contain 3-deoxy-3-[(R)-3-hydroxybutanoylamino]-d-fucose (d-Fuc3NR3Hb) and the following structure of the heptasaccharide repeating unit was established: The structure established is consistent with the gene content of the O-antigen gene cluster. The O-polysaccharide structure and gene cluster of Y.

Changes in the lipopolysaccharide of Proteus mirabilis 9B-m (O11a) clinical strain in response to planktonic or biofilm type of growth.

The impact of planktonic and biofilm lifestyles of the clinical isolate Proteus mirabilis 9B-m on its lipopolysaccharide (O-polysaccharide, core region, and lipid A) was evaluated. Proteus mirabilis bacteria are able to form biofilm and lipopolysaccharide is one of the factors involved in the biofilm formation. Lipopolysaccharide was isolated from planktonic and biofilm cells of the investigated strain and analyzed by SDS-PAGE with silver staining, Western blotting and ELISA, as well as NMR and matrix-assisted laser desorption ionization time-of-flight mass spectrometry techniques.

The O-antigen structure of bacterium Comamonas aquatica CJG.

Genus Comamonas is a group of bacteria that are able to degrade a variety of environmental waste. Comamonas aquatica CJG (C. aquatica) in this genus is able to absorb low-density lipoprotein but not high-density lipoprotein of human serum.

Structure and gene cluster of a tyvelose-containing O-polysaccharide of an entomopathogenic bacterium Yersinia entomophaga MH96 related to Yersinia pseudotuberculosis.

An O-polysaccharide was isolated from the lipopolysaccharide of an entomopathogenic bacterium Yersinia entomophaga MH96 by mild acid hydrolysis and studied by 2D NMR spectroscopy. The following structure of the branched tetrasaccharide repeating unit of the polysaccharide was established: where Tyv indicates 3,6-dideoxy-d-arabino-hexose (tyvelose). The structure established is consistent with the gene content of the O-antigen gene cluster.

Halloysite nanotubes with immobilized silver nanoparticles for anti-bacterial application.

Halloysite nanotubes (HNTs) with immobilized silver (Ag) nanoparticles (NPs) were prepared by methods of wet chemistry and were characterized by using the transmission electron microscopy, x-ray diffraction, optical spectroscopy and experiments with E. coli bacteria in-vitro. It was found that Ag NPs with almost perfect crystalline structure and sizes from ∼9nm were mainly attached over the external surface of HNTs.

Structures and serospecificity of threonine-containing O polysaccharides of two clinical isolates belonging to the genus Proteus and their classification into O11 subserogroups.

Two clinical isolates from Polish patients, Proteus mirabilis 9B-m and Proteus genomospecies 3J-r, were found to be serologically related to P mirabilis O11. However, serological studies involving ELISA and Western blotting methods, using lipopolysaccharides (LPSs) extracted from the strains as antigens and native or adsorbed rabbit polyclonal O antisera, specific to the studied strains, revealed slight differences in the cross-reactivity and specificity of the two studied Proteus isolates, when compared to P. mirabilis O11.

Structural Relationship of the Lipid A Acyl Groups to Activation of Murine Toll-Like Receptor 4 by Lipopolysaccharides from Pathogenic Strains of Burkholderia mallei, Acinetobacter baumannii, and Pseudomonas aeruginosa.

Toll-like receptor 4 (TLR4) is required for activation of innate immunity upon recognition of lipopolysaccharide (LPS) of Gram-negative bacteria. The ability of TLR4 to respond to a particular LPS species is important since insufficient activation may not prevent bacterial growth while excessive immune reaction may lead to immunopathology associated with sepsis. Here, we investigated the biological activity of LPS from Burkholderia mallei that causes glanders, and from the two well-known opportunistic pathogens Acinetobacter baumannii and Pseudomonas aeruginosa (causative agents of nosocomial infections).

Carbohydrate Structure Database: tools for statistical analysis of bacterial, plant and fungal glycomes.

Carbohydrates are biological blocks participating in diverse and crucial processes both at cellular and organism levels. They protect individual cells, establish intracellular interactions, take part in the immune reaction and participate in many other processes. Glycosylation is considered as one of the most important modifications of proteins and other biologically active molecules.

Distinct biological activity of lipopolysaccharides with different lipid A acylation status from mutant strains of Yersinia pestis and some members of genus Psychrobacter.

Correlation between the chemical structure of lipid A from various Gram-negative bacteria and biological activity of their lipopolysaccharide (LPS) as an agonist of the innate immune receptor Toll-like receptor 4 was investigated. Purified LPS species were quantitatively evaluated by their ability to activate the production of tumor necrosis factor (TNF) by murine bone marrow-derived macrophages in vitro. Wild-type LPS from plague-causing bacteria Yersinia pestis was compared to LPS from mutant strains with defects in acyltransferase genes (lpxM, lpxP) responsible for the attachment of secondary fatty acid residues (12:0 and 16:1) to lipid A.

Structure of a zwitterionic O-polysaccharide from Photorhabdus temperata subsp. cinerea 3240.

A phosphorylated O-polysaccharide was isolated from the lipopolysaccharide of an entomopathogenic bacterium Photorhabdus temperata subsp. cinerea 3240 and studied by sugar analysis, dephosphorylation, and (1)H and (13)C NMR spectroscopy. The following structure of the linear trisaccharide repeating unit of the O-polysaccharide was established: →3)-β-D-GalpNAc4PEtN-(1→4)-β-D-GlcpA-(1→3)-β-D-FucpNAc4N-(1→ where GlcA indicates glucuronic acid, FucNAc4N 2-acetamido-4-amino-2,4,6-trideoxygalactose, and PEtN 2-aminoethyl phosphate.

Assessing copy number from exome sequencing and exome array CGH based on CNV spectrum in a large clinical cohort.

Purpose: Detection of copy-number variation (CNV) is important for investigating many genetic disorders. Testing a large clinical cohort by array comparative genomic hybridization provides a deep perspective on the spectrum of pathogenic CNV. In this context, we describe a bioinformatics approach to extract CNV information from whole-exome sequencing and demonstrate its utility in clinical testing.

Structure of the O-polysaccharide of Photorhabdus temperata subsp. temperata XlNach(T) containing a novel branched monosaccharide, 3,6-dideoxy-4-C-[(S)-1,2-dihydroxyethyl]-d-xylo-hexose.

O-Polysaccharide was isolated from the lipopolysaccharide of an entomopathogenic bacterium Photorhabdus temperata subsp. temperata XlNach(T). Sugar analysis after full acid hydrolysis of the polysaccharide revealed D-glucose, D-mannose, D-galactose, D-GalNAc, and a branched monosaccharide, 3,6-dideoxy-4-C-[(S)-1',2'-dihydroxyethyl]-D-xylo-hexose (Sug), which was isolated as a 1,2'-anhydro furanose derivative.

Structure of the O-polysaccharide of Pseudomonas mandelii CYar1 containing 3,6-dideoxy-4-C-[(S)-1-hydroxyethyl]-D-xylo-hexose (yersiniose A).

The O-polysaccharide isolated by mild acid hydrolysis of the lipopolysaccharide of Pseudomonas mandelii CYar1 was studied by sugar analysis and 1D and 2D (1)H and (13)C NMR spectroscopies. The following structure of the O-polysaccharide was established:

Structure of the alanopine-containing O-polysaccharide and serological cross-reactivity of the lipopolysaccharide of Proteus vulgaris HSC 438 classified into a new Proteus serogroup, O76.

The O-polysaccharide was isolated by mild acid hydrolysis of the lipopolysaccharide of Proteus vulgaris HSC 438, and the following structure was established by chemical methods and one- and two-dimensional (1)H and (13)C NMR spectroscopy: →3)-β-d-Quip4NAlo-(1→3)-α-d-Galp6Ac-(1→6)-α-d-Glcp-(1→3)-α-l-FucpNAc-(1→3)-β-d-GlcpNAc-(1→, where d-Qui4N stands for 4-amino-4,6-dideoxy-d-glucose and Alo for N-((S)-1-carboxyethyl)-l-alanine (alanopine); only about half of the Gal residues are O-acetylated. This structure is unique among the Proteus O-polysaccharides, and therefore it is proposed to classify P. vulgaris HSC 438 into a new Proteus serogroup, O76.

Structure of the O-specific polysaccharide from the lipopolysaccharide of Psychrobacter cryohalolentis K5(T) containing a 2,3,4-triacetamido-2,3,4-trideoxy-L-arabinose moiety.

A novel constituent of bacterial polysaccharides, 2,3,4-triacetamido-2,3,4-trideoxy-L-arabinose, was found in the O-specific polysaccharide from the lipopolysaccharide of Psychrobacter cryohalolentis K5(T) and identified by 1D and 2D (1)H and (13)C NMR studies of the polysaccharide and a disaccharide obtained by solvolysis of the polysaccharide with triflic acid. The following structure of the branched polysaccharide was established by sugar analysis, triflic acid solvolysis, Smith degradation, and 2D NMR spectroscopy.

Structure of the O-polysaccharide of Providencia alcalifaciens O3 containing 3,6-dideoxy-3-formamido-D-glucose and D-galacturonamide.

Mild acid degradation of the lipopolysaccharide (LPS) of Providencia alcalifaciens O3 followed by GPC on Sephadex G-50 and anion-exchange chromatography on DEAE-Trisacryl M afforded neutral and acidic polysaccharides, LPS core oligosaccharide, and an oligosaccharide composed of one repeat of the neutral polysaccharide (O-unit) linked to the LPS core. The following structure of the pentasaccharide O-unit was established by sugar and methylation analyses, 2D (1)H and (13)C NMR spectroscopy and ESI MS: [formula: see text] where Qui3NFo stands for 3,6-dideoxy-3-formamidoglucose and GalAN for galacturonamide. The LPS core is represented by the Glc(3)Gal(1)GalA(1)Hep(3)Kdo(1)Ara4N(1)P(3)EtN(2) glycoform reported earlier for P.

Structure of an acidic polysaccharide isolated from Psychrobacter maritimus 3pS containing a bacillosamine derivative.

An acidic polysaccharide was obtained from Psychrobacter maritimus 3pS isolated from a Siberian cryopeg sample (Kolyma lowland). The following structure of the tetrasaccharide repeating unit of the polysaccharide was established by sugar analysis along with (1)H and (13)C NMR spectroscopy: →2)-α-L-Rhap-(1→4)-α-D-GalpNAcA-(1→3)-α-D-QuipNAc4NHb-(1→3)-β-D-QuipNAc4NHb-(1→ where D-GalNAcA indicates 2-acetamido-2-deoxy-D-galacturonic acid and d-QuiNAc4NHb indicates 2-acetamido-2,4,6-trideoxy-4-[(S)-3-hydroxybutanoyl]amino-D-glucose.

Structure of a peptidoglycan-related polysaccharide from Providencia alcalifaciens O45.

A polysaccharide was isolated from the opportunistic human pathogen Providencia alcalifaciens O45:H26 by extraction with aqueous phenol and studied by sugar and methylation analyses along with (1)H and (13)C NMR spectroscopy, including two-dimensional ROESY and H-detected (1)H,(13)C HSQC experiments. The polysaccharide contains N-acetylglucosamine and N-acetylmuramic acid (D-GlcpNAc3Rlac) amidated with L-alanine and has the following structure: →4)-β-D-GlcpNAc-(1→4)-β-D-GlcpNAc3(Rlac-L-Ala)-(1→. The polysaccharide possesses a remarkable structural similarity to the bacterial cell wall peptidoglycan.

Structure of the O-polysaccharide of Photorhabdus luminescens subsp. laumondii containing D-glycero-D-manno-heptose and 3,6-dideoxy-3-formamido-D-glucose.

The O-polysaccharide from the lipopolysaccharide of a symbiotic bacterium Photorhabdus luminescens subsp. laumondii TT01 from an insect-pathogenic nematode was studied by sugar analysis and (1)H and (13)C NMR spectroscopy and found to contain D-glycero-D-manno-heptose (DDHep) and 3,6-dideoxy-3-formamido-D-glucose (D-Qui3NFo). The following structure of the pentasaccharide repeating unit of the O-polysaccharide was established:

Revision of the O-polysaccharide structure of Yersinia pseudotuberculosis O:1a; confirmation of the function of WbyM as paratosyltransferase.

An O-polysaccharide was isolated by mild acid degradation at pH 4.5 of the long-chain lipopolysaccharide of Yersinia pseudotuberculosis PB1 (serotype O:1a) and studied using 2D NMR spectroscopy. It was found to contain two uncommon monosaccharides: paratose (3,6-dideoxy-d-ribo-hexose, Par) in the furanose form and 6-deoxy-d-manno-heptose (d-6dmanHep).

Structure of the O-polysaccharide chain of the lipopolysaccharide of Psychrobacter muricolla 2pS(T) isolated from overcooled water brines within permafrost.

Psychrotrophic bacteria of the genus Psychrobacter have not been studied in respect to lipopolysaccharide structure. In this work, we determined the structure of the O-specific polysaccharide of the lipopolysaccharide of Psychrobacter muricolla 2pS(T) isolated from overcooled (-9°C) water brines within permafrost. The polysaccharide was found to be acidic due to the presence of an amide of 2-acetamido-2-deoxy-l-guluronic acid with glycine (l-GulNAcA6Gly), which has not been hitherto found in nature.

Functional characterization and biological significance of Yersinia pestis lipopolysaccharide biosynthesis genes.

In silico analysis of available bacterial genomes revealed the phylogenetic proximity levels of enzymes responsible for biosynthesis of lipopolysaccharide (LPS) of Yersinia pestis, the cause of plague, to homologous proteins of closely related Yersinia spp. and some other bacteria (Serratia proteamaculans, Erwinia carotovora, Burkholderia dolosa, Photorhabdus luminescens and others). Isogenic Y.

Structure of the O-polysaccharide from the lipopolysaccharide of Providencia alcalifaciens O28.

An O-polysaccharide and oligosaccharides were isolated by GPC following mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O28. The O-polysaccharide was studied by sugar and methylation analyses, (1)H and (13)C NMR spectroscopy, including 2D ROESY and H-detected (1)H,(13)C HSQC and HMBC experiments, and the following structure of the branched pentasaccharide repeating unit was established: [see formula in text]. This structure was confirmed by ESI MS of the isolated tridecasaccharide consisting of the lipopolysaccharide core and one O-polysaccharide repeat.