Lipopolysaccharides core oligosaccharide

Ortega, X., Silipo, A., Saldfas, M.S., Bates, C.C., Molinaro, A., Valvano, M.A. Biosynthesis and structure of the Burkholderia cenocepacia K56-2 lipopolysaccharide core oligosaccharide truncation of the core oligosaccharide leads to increased binding and sensitivity to polymyxin B. J Biol Chem 284(32) (2009) 21738-21751. 

FIGURE 7-32 Bacterial lipopolysaccharides. (a) Schematic diagram of the lipopolysaccharide of the outer membrane of Salmonella ty-phimurium. Kdo is 3-deoxy-o-manno-octulosonic acid, previously called ketodeoxyoctonic acid Hep is L-glycero-D-mannoheptose AbeOAc is abequose (a 3,6-dideoxyhexose) acetylated on one of its hydroxyls. There are six fatty acids in the lipid A portion of the molecule. Different bacterial species have subtly different lipopolysaccharide structures, but they have in common a lipid region (lipid A), a core oligosaccharide, and an "O-specific" chain, which is the prin-... 

Abstract Lipopolysaccharides are the major components on the surface of most Gram-negative bacteria, and recognized by immune cells as a pathogen-associated molecule. They can cause severe diseases like sepsis and therefore known as endotoxins. Lipopolysaccharide consists of lipid A, core oligosaccharide and O-antigen repeats. Lipid A is responsible for the major bioactivity of endotoxin. Because of their specific structure and amphipathic property, purification and analysis of lipopolysaccharides are difficult. In this chapter, we summarize the available approaches for extraction, purification and analysis of lipopolysaccharides. 

Holst, O., Molinaro, A. 2009. Core oligosaccharide and lipid A components of lipopolysaccharides. In Moran, A., Brennan, P., Holst, O., von Itszstein, M. (eds), Microbial Glycobiology Structures Relevance and Applications. Elsevier, San Diego, CA, pp. 29-56. 

Isshiki, Y., Zahringer, U., Kawahara, K. Structure of the core oligosaccharide with a characteristic D-glycero-a-D-talo-oct-2-ulosonate-(2- -4)-3-deoxy-D-manno-oct-2-ulosonate [a-Ko-(2- -4)-Kdo] disaccharide in the lipopolysaccharide of Burkholderia cepacia. Carbohydr Res 338 (2003) 2659-2666. 

Fig. 9.1 The structure of lipopolysaccharide, LPS. LPS consists of an O-specific antigen, a core oligosaccharide and the lipid A moiety. The core oligosaccharide, which varies from one bacterial species to another, is made up of outer and inner sugar regions. Lipid A virtually always includes two glucosamine residues modified by phosphates and a variable number of fatty acid chains (Frecer et al., 2000). The LPS structure was kindly contributed by Professor Helmut Brade (Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Medical and Biochemical Mikrobiology Parkallee 22, D-23845 Borstel, Germany)...

Like Escherichia coli, clinical isolates of H. pylori produce high-molecular-mass (smooth-form) lipopolysaccharide (LPS) composed of an outermost saccharide moiety, divided into the O-polysaccharide or O-specific chain (O-antigen) and core oligosaccharide (OS) regions, covalently linked to lipid A (Fig. 10.1). H. pylori smooth-form LPS possesses O-polysaccharide chains of relatively constant chain length compared with those of enterobacterial LPS (Moran et al., 1992a Moran, 1999). Their length is determined by an enzymatic molecular ruler mechanism... 

Molinaro, A., De Castro, C., Lanzetta, R., Parrilli, M., Raio, A., Zoina, A. Structural elucidation of a novel core oligosaccharide backbone of the lipopolysaccharide from the new bacterial species Agrobacterium larrymoorei. Carbohydr Res 338 (2003) 2721-2730. 

Lipopolysaccharide core structures are, as mentioned, phosphorylated. The phosphate groups complicate the separation and purification and consequently the structure elucidation of core structures, and these were therefore formerly often performed on dephosphorylated material. However, with the techniques of today it is generally possible also to establish the phosphorylation pattern of the native structures, giving an additional challenge to the synthetic chemist to synthesise phosphorylated oligosaccharide structures to be used as tools in the evaluation of the biological role of the phosphate groups. 

Aspinall GO, McDonald AG, Pang H, Kurjanczyk LA, Penner JL (1994b) Lipopolysaccharides of Campylobacter jejuni serotype 0 19 Structures of core oligosaccharide regions from the serostrain and two bacterial isolates from patients with the Guillain-Barre syndrome. Biochemistry 33 241-249. 

G. O. Aspinall, and M. A. Monteiro, Lipopolysaccharides of Helicobacter pylori strains P466 and MO 19 Structures of the O antigen and core oligosaccharide regions, Biochemistry, 35 (1996) 2498-2504. 

Constit. of the outer core oligosaccharide which constitutes part of the Shigella sonnei. Shigella Jlexneri 6 and Escherichia coli C lipopolysaccharide. 

The lipopolysaccharides have been isolated from two wild-type strains of E. coli K12, two core-deficient mutants, and an SR recombinant with Salmonella typhimurium Methylation analysis of the oligosaccharides released on dephosphorylation of the lipopolysaccharides revealed differences in the extents of completion of the core structures. The non-reducing end of the complete core structure of lipopolysaccharides from the E. coli K12 wild-type strains is substituted with either 2-acetamido-2-deoxy-D-glucose or, possibly, 2-acetamido-2-deoxy-D-mannopyranosyluronic acid, whereas the complete K12 core in the SR recombinant is substituted with an S-specific oligosaccharide of S. typhimurium. These substituents are attached to 0-6 of the D-glucopyranosyl residue at the non-reducing end of the core oligosaccharide, as shown in (8). 

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