The sugar 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) as a characteristic component of bacterial endotoxin — a review of its biosynthesis, function, and placement in the lipopolysaccharide core

2013 ◽  
Vol 59 (10) ◽  
pp. 645-655 ◽  
Author(s):  
Jolanta Lodowska ◽  
Daniel Wolny ◽  
Ludmiła Węglarz
Keyword(s):  
Lipid A ◽  
Inner Core ◽  
Structural Diversity ◽  
Core Region ◽  
Bacterial Lipopolysaccharide ◽  
Bacterial Endotoxin ◽  
Bacterial Cells ◽  
Ulosonic Acid ◽  
Characteristic Component ◽  
Acid Labile

The sugar 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) is a characteristic component of bacterial lipopolysaccharide (LPS, endotoxin). It connects the carbohydrate part of LPS with C6 of glucosamine or 2,3-diaminoglucose of lipid A by acid-labile α-ketosidic linkage. The number of Kdo units present in LPS, the way they are connected, and the occurrence of other substituents (P, PEtn, PPEtn, Gal, or β-l-Ara4N) account for structural diversity of the inner core region of endotoxin. In a majority of cases, Kdo is crucial to the viability and growth of bacterial cells. In this paper, the biosynthesis of Kdo and the mechanism of its incorporation into the LPS structure, as well as the location of this unique component in the endotoxin core structures, have been described.

scholarly journals Genetic and Structural Characterization of the Core Region of the Lipopolysaccharide from Serratia marcescens N28b (Serovar O4)

2004 ◽  
Vol 186 (4) ◽  
pp. 978-988 ◽  
Author(s):  
Núria Coderch ◽  
Núria Piqué ◽  
Buko Lindner ◽  
Nihal Abitiu ◽  
Susana Merino ◽  
...  
Keyword(s):  
Serratia Marcescens ◽  
Gene Cluster ◽  
Inner Core ◽  
Core Region ◽  
Complementation Analysis ◽  
Ionization Mass ◽  
Ion Cyclotron Resonance ◽  
The Core ◽  
K 12 ◽  
Ulosonic Acid

ABSTRACT The gene cluster (waa) involved in Serratia marcescens N28b core lipopolysaccharide (LPS) biosynthesis was identified, cloned, and sequenced. Complementation analysis of known waa mutants from Escherichia coli K-12, Salmonella enterica, and Klebsiella pneumoniae led to the identification of five genes coding for products involved in the biosynthesis of a shared inner core structure: [l,d-HeppIIIα(1→7)-l,d-HeppIIα(1→3)-l,d-HeppIα(1→5)-KdopI(4←2)αKdopII] (l,d-Hepp, l-glycero-d-manno-heptopyranose; Kdo, 3-deoxy-d-manno-oct-2-ulosonic acid). Complementation and/or chemical analysis of several nonpolar mutants within the S. marcescens waa gene cluster suggested that in addition, three waa genes were shared by S. marcescens and K. pneumoniae, indicating that the core region of the LPS of S. marcescens and K. pneumoniae possesses additional common features. Chemical and structural analysis of the major oligosaccharide from the core region of LPS of an O-antigen-deficient mutant of S. marcescens N28b as well as complementation analysis led to the following proposed structure: β-Glc-(1→6)-α-Glc-(1→4))-α-d-GlcN-(1→4)-α-d-GalA-[(2←1)-α-d,d-Hep-(2←1)-α-Hep]-(1→3)-α-l,d-Hep[(7←1)-α-l,d-Hep]-(1→3)-α-l,d-Hep-[(4←1)-β-d-Glc]-(1→5)-Kdo. The D configuration of the β-Glc, α-GclN, and α-GalA residues was deduced from genetic data and thus is tentative. Furthermore, other oligosaccharides were identified by ion cyclotron resonance-Fourier-transformed electrospray ionization mass spectrometry, which presumably contained in addition one residue of d-glycero-d-talo-oct-2-ulosonic acid (Ko) or of a hexuronic acid. Several ions were identified that differed from others by a mass of +80 Da, suggesting a nonstoichiometric substitution by a monophosphate residue. However, none of these molecular species could be isolated in substantial amounts and structurally analyzed. On the basis of the structure shown above and the analysis of nonpolar mutants, functions are suggested for the genes involved in core biosynthesis.

scholarly journals Lipopolysaccharide O-antigens—bacterial glycans made to measure

2020 ◽  
Vol 295 (31) ◽  
pp. 10593-10609 ◽  
Author(s):  
Chris Whitfield ◽  
Danielle M. Williams ◽  
Steven D. Kelly
Keyword(s):  
Chain Length ◽  
Cell Biology ◽  
Lipid A ◽  
Length Distribution ◽  
Structural Diversity ◽  
Biological Properties ◽  
Chemical Diversity ◽  
Permeability Barrier ◽  
Bacterial Cells ◽  
Chain Length Distribution

Lipopolysaccharides are critical components of bacterial outer membranes. The more conserved lipid A part of the lipopolysaccharide molecule is a major element in the permeability barrier imposed by the outer membrane and offers a pathogen-associated molecular pattern recognized by innate immune systems. In contrast, the long-chain O-antigen polysaccharide (O-PS) shows remarkable structural diversity and fulfills a range of functions, depending on bacterial lifestyles. O-PS production is vital for the success of clinically important Gram-negative pathogens. The biological properties and functions of O-PSs are mostly independent of specific structures, but the size distribution of O-PS chains is particularly important in many contexts. Despite the vast O-PS chemical diversity, most are produced in bacterial cells by two assembly strategies, and the different mechanisms employed in these pathways to regulate chain-length distribution are emerging. Here, we review our current understanding of the mechanisms involved in regulating O-PS chain-length distribution and discuss their impact on microbial cell biology.

scholarly journals Structure of the lipid A–inner core region and biological activity of Plesiomonas shigelloides O54 (strain CNCTC 113/92) lipopolysaccharide

Glycobiology ◽  
2006 ◽  
Vol 16 (6) ◽  
pp. 538-550 ◽  
Author(s):  
Jolanta Lukasiewicz ◽  
Tomasz Niedziela ◽  
Wojciech Jachymek ◽  
Lennart Kenne ◽  
Czeslaw Lugowski
Keyword(s):  
Biological Activity ◽  
Lipid A ◽  
Inner Core ◽  
Core Region ◽  
Plesiomonas Shigelloides

Lipopolysaccharides fromSerratia marcescens Possess One or Two 4-Amino-4-deoxy-L-arabinopyranose 1-Phosphate Residues in the Lipid A andD-glycero-D-talo-Oct-2-ulopyranosonic Acid in the Inner Core Region

2006 ◽  
Vol 12 (25) ◽  
pp. 6692-6700 ◽  
Author(s):  
Evgeny Vinogradov ◽  
Buko Lindner ◽  
Guntram Seltmann ◽  
Joanna Radziejewska-Lebrecht ◽  
Otto Holst
Keyword(s):  
Lipid A ◽  
Inner Core ◽  
Core Region

scholarly journals Characterization of the Xanthomonas campestris pv. campestris Lipopolysaccharide Substructures Essential for Elicitation of an Oxidative Burst in Tobacco Cells

2005 ◽  
Vol 18 (7) ◽  
pp. 674-681 ◽  
Author(s):  
Sebastian G. Braun ◽  
Andreas Meyer ◽  
Otto Holst ◽  
Alfred Pühler ◽  
Karsten Niehaus
Keyword(s):  
Cell Cultures ◽  
Oxidative Burst ◽  
Xanthomonas Campestris ◽  
Lipid A ◽  
Inner Core ◽  
Core Region ◽  
Tobacco Cell ◽  
Tobacco Cells ◽  
O Antigen ◽  
Xanthomonas Campestris Pv Campestris

The lipopolysaccharides (LPS) of gram-negative bacteria are essential for perception of pathogens by animals and plants. To identify the LPS substructure or substructures recognized by plants, we isolated water-phase (w)LPS from different Xanthomonas campestris pv. campestris mutants and analyzed their sugar content and ability to elicit an oxidative burst in tobacco cell cultures. The different wLPS species are characterized by lacking repetitive subunits of the O-antigen, the complete O-antigen, or even most of the core region. Because loss of lipid A would be lethal to bacteria, pure lipid A was obtained from X. campestris pv. campestris wild-type wLPS by chemical hydrolysis. The elicitation experiments with tobacco cell cultures revealed that LPS detection is dependent on the bioavailability of the amphiphilic wLPS, which can form micelles in an aqueous environment. By adding deoxycholate to prevent micelle formation, all of the tested wLPS species showed elicitation capability, whereas the lipid A alone was not able to trigger an oxidative burst or calcium transients in tobacco cell cultures. These results suggest that the LPS substructure recognized by tobacco cells is localized in the inner core region of the LPS, consisting of glucose, galacturonic acid, and 3-deoxy-d-manno-oct-2-ulosonic acids. Although lipid A alone seems to be insufficient to induce an oxidative burst in tobacco cell cultures, it cannot be ruled out that lipid A or the glucosamine backbone may be important in combination with the inner core structures.

scholarly journals Granulibacter bethesdensis, a Pathogen from Patients with Chronic Granulomatous Disease, Produces a Penta-Acylated Hypostimulatory Glycero-d-talo-oct-2-ulosonic Acid–Lipid A Glycolipid (Ko-Lipid A)

2021 ◽  
Vol 22 (7) ◽  
pp. 3303
Author(s):  
Artur Muszyński ◽  
Kol A. Zarember ◽  
Christian Heiss ◽  
Joseph Shiloach ◽  
Lars J. Berg ◽  
...  
Keyword(s):  
Chronic Granulomatous Disease ◽  
Human Blood ◽  
Lipid A ◽  
Acid Resistance ◽  
Strong Acid ◽  
Granulomatous Disease ◽  
E Coli ◽  
Phagocyte Nadph Oxidase ◽  
Acyl Chains ◽  
Ulosonic Acid

Granulibacter bethesdensis can infect patients with chronic granulomatous disease, an immunodeficiency caused by reduced phagocyte NADPH oxidase function. Intact G. bethesdensis (Gb) is hypostimulatory compared to Escherichia coli, i.e., cytokine production in human blood requires 10–100 times more G. bethesdensis CFU/mL than E. coli. To better understand the pathogenicity of G. bethesdensis, we isolated its lipopolysaccharide (GbLPS) and characterized its lipid A. Unlike with typical Enterobacteriaceae, the release of presumptive Gb lipid A from its LPS required a strong acid. NMR and mass spectrometry demonstrated that the carbohydrate portion of the isolated glycolipid consists of α-Manp-(1→4)-β-GlcpN3N-(1→6)-α-GlcpN-(1⇿1)-α-GlcpA tetra-saccharide substituted with five acyl chains: the amide-linked N-3′ 14:0(3-OH), N-2′ 16:0(3-O16:0), and N-2 18:0(3-OH) and the ester-linked O-3 14:0(3-OH) and 16:0. The identification of glycero-d-talo-oct-2-ulosonic acid (Ko) as the first constituent of the core region of the LPS that is covalently attached to GlcpN3N of the lipid backbone may account for the acid resistance of GbLPS. In addition, the presence of Ko and only five acyl chains may explain the >10-fold lower proinflammatory potency of GbKo–lipidA compared to E. coli lipid A, as measured by cytokine induction in human blood. These unusual structural properties of the G.bethesdensis Ko–lipid A glycolipid likely contribute to immune evasion during pathogenesis and resistance to antimicrobial peptides.

Experimental and simulation study of impurity transport response to RMPs in RF-heated H-mode plasmas at EAST

2021 ◽  
Vol 87 (2) ◽  
Author(s):  
Germán Vogel ◽  
Hongming Zhang ◽  
Yongcai Shen ◽  
Shuyu Dai ◽  
Youwen Sun ◽  
...  
Keyword(s):  
Inner Core ◽  
Extreme Ultraviolet ◽  
Transport Coefficients ◽  
Three Dimensional ◽  
Line Emission ◽  
Core Region ◽  
Emission Mitigation ◽  
One Dimensional ◽  
Impurity Transport ◽  
Transport Code

Spatial profiles of impurity emission measurements in the extreme ultraviolet (EUV) spectroscopic range in radiofrequency (RF)-heated discharges are combined with one-dimensional and three-dimensional transport simulations to study the effects of resonant magnetic perturbations (RMPs) on core impurity accumulation at EAST. The amount of impurity line emission mitigation by RMPs appears to be correlated with the ion Z for lithium, carbon, iron and tungsten monitored, i.e. stronger suppression of accumulation for heavier ions. The targeted effect on the most detrimental high-Z impurities suggests a possible advantage using RMPs for impurity control. Profiles of transport coefficients are calculated with the STRAHL one-dimensional impurity transport code, keeping $\nu /D$ fixed and using the measured spatial profiles of $\textrm{F}{\textrm{e}^{20 + }}$ , $\textrm{F}{\textrm{e}^{21 + }}$ and $\textrm{F}{\textrm{e}^{22 + }}$ to disentangle the transport coefficients. The iron diffusion coefficient ${D_{\textrm{Fe}}}$ increases from $1.0- 2.0\;{\textrm{m}^2}\;{\textrm{s}^{ - 1}}$ to $1.5- 3.0\;{\textrm{m}^2}\;{\textrm{s}^{ - 1}}$ from the core region to the edge region $(\rho \gt 0.5)$ after the onset of RMPs. Meanwhile, an inward pinch of iron convective velocity ${\nu _{\textrm{Fe}}}$ decreases in magnitude in the inner core region and increases significantly in the outer confined region, simultaneously contributing to preserving centrally peaked $\textrm{Fe}$ profiles and exhausting the impurities. The ${D_{\textrm{Fe}}}$ and ${\nu _{\textrm{Fe}}}$ variations lead to reduced impurity contents in the plasma. The three-dimensional edge impurity transport code EMC3-EIRENE was also applied for a case of RMP-mitigated high-Z accumulation at EAST and compared to that of low-Z carbon. The exhaust of ${\textrm{C}^{6 + }}$ toward the scrape-off layer accompanying an overall suppression of heavier ${\textrm{W}^{30 + }}$ is observed when using RMPs.

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