O-Antigenic chains

Figure 1 represents the general structure of Salmonella lipopolysaccharides. They contain an external polysaccharide, the O-antigenic chain, and an innermost component, termed lipid A. O-chain and lipid A are linked to each other by an oligosaccharide referred to as the core. O-Specific Chains. As indicated in Figure 1, O chains are in general made up of repeating units of di-, tri-, or higher oligosaccharides. In rare cases the O-chain is a homopolysaccharide. The structure of the O-chain is unique to each bacterial serotype great diversity is encountered in the structures of O-chains.

Larue, K., Kimber, M.S., Ford, R., Whitfield, C. Biochemical and structural analysis of bacterial O-antigen chain length regulator proteins reveals a conserved quaternary structure. J Biol Chem 284 (2009) 7395-7403. 

Delgado, M., Mouslim, C., Groisman, E. The PmrA/PmrB and RcsC/YojN/RcsB systems control expression of the Salmonella O-antigen chain length determinant. Mol Microbiol 60 (2006) 39-50. 

Morona, R., van den Bosch, L., Manning, P. Molecular, genetic, and topological characterization of O-antigen chain length regulation in Shigella flexneri. J Bacteriol 177 (1995) 1059-1068. 

The O Antigen Chain Lengths is Important for the Full Virulence... 

Franco, V.A., Liu, D., Reeves, P.R. The Wzz (Cld) protein in Escherichia coli amino acid sequence variation determines O antigen chain length specificity. J Bacteriol 180 (1998) 2670-2675. 

Reeves, P.R., Cunneen, M.M. Biosynthesis of O-antigen chains and assembly. In Moran, A., Brennan, P., Holst, O., Itzstein, M.v. (eds), Microbial Glycobiology Structures, Relevance and Applications, Academic, New York, NY (2009). 

G. O. Aspinall, M. A. Monteiro, H. Pang, E. J. Walsh, and A. P. Moran, Lipopolysaccharide of the Helicobacter pylori type strain NCTC 11637 (ATCC 43504) Structure of the O antigen chain and core oligosaccharide regions, Biochemistry, 35 (1996) 2489-2497. 

G. O. Aspinall, A. G. McDonald, and H. Pang, Lipopolysaccharides of Campylobacter jejuni serotype 0 19 Structures of O antigen chains from the serostrain and two bacterial isolates from patients with the Guillain-Barre syndrome, Biochemistry, 33 (1994) 250-255. 

Figure 8 Proposed pathway for pilin O-glycosylation in Pseudomonas aeruginosa 1244. WbpL, UDP-FucNAc Und-P FucNAc-1-P transferase Wzx, flippase Wzy, O antigen poiymerase Wzz, O antigen chain iength reguiator. 5NbOHC47NFmPse, 5-N-b-hydroxybutyryi-7-A/-formyi-pseudaminic acid.

O-antigen chain is transferred from imdecaprenol diphosphate onto the lipopolysaccharide core. This apparently occurs on the periplasmic surface of the plasma membrane. If so, the core lipid domain must be flipped across the plasma membrane before the... 

O-antigen chain is attached. Less is knovm about the transport of the completed lipopolysaccharide across the periplasmic space and into the outer membrane. 

C7H14O7 210.183 Component of O antigen chains in lipopolysaccharides from Campylobacter jejuni serotypes 023 and 036. 

In neuroinvasive E. coli K1 and meningitidis, functions as a neurotropic determinant facilitates invasion of the blood-brain barrier and colonization of the meninges of neonatal brains Polyanionic shield that masks the somatic O-antigen chains of lipopolysaccharide and renders cell resistant to immune detection and phagocytosis Receptor for binding K1-specific bacteriophages... 

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