Salmonella O-Antigen Polysaccharides

V Shibaev Biosynthesis of salmonella O-antigenic polysaccharide specificity of glycosyl transferases... 

Bock K, Meldal M, Bundle DR, Iversen T, Garegg PJ, Norbeig T, Lindberg AA, Svenson SB (1984) The conformation of Salmonella O-antigenic polysaccharide chains of serogroup A, B and D1 predicted by semi-empirical hard-sphere (HSEA) calculations. Carbohydr Res 130 23-34... 

L.V. (1981). Synthesis of the O-antigenic polysaccharide of Salmonella newington and of its analogue differing in configuration at the only glycosidic centre. Tetrahedron 37 Suppl. 1 19-156 Lehmann, V. (1977). Isolation, purification, and properties of an... 

Figure 3. Structures of the O-antigenic polysaccharide chain in Salmonella bacteria of serogroups C2 and C3 and a synthetic disaccharide glycoconjugate (O-antigen 8-specific). Results of immunofluorescence studies (IFL) of these structures.

The structure of the O-antigenic polysaccharide chain in Salmonella serogroup Cl (0 antigens 6, 7) has not been established in detail (22). Hence, it has not been possible to identify the structural elements representing the determinant of serogroup 0-antigen 07. 

Figure 4. Structures of the O-antigenic polysaccharide chains in Salmonella bacteria ofserogroup E and a synthetic trisaccharide gly coconjugate (O-antigen 3-specific). Results of ELISA and immunofluorescence (IFL) studies. Key m, S. anatum (03, 10) , S. senftenburg (01, 3, 19) , BSA a, S. typhimurium (04, 5,...

TABLE I. Salmonella typhimurium Infection in Calves Delayed Skin Reactivity with Specificity for O-Antigenic Polysaccharide Chain... 

B. A. Dmitriev, A. V. Nikolaev, A. S. Shashkov, and N. K. Kochetkov, Block-synthesis of higher oligosaccharides Synthesis of hexa- and nona-saccharide fragments of the O-antigenic polysaccharide of Salmonella newington, Carbohydr. Res., 100 (1982) 195-206. 

FIGURE 14.3 Structure of LPS with the core structure from Escherichia coli and the Salmonella species. Gal, galactose Glc, glucose Hep, L-glycero-D-manno-heptose O-PS, O-antigen polysaccharide. 

Constit. of the O-antigenic polysaccharide attached to the cell wall of Salmonella bacteria serogroup E2. 

C18H32O16 504.441 Constituent of the main chain of O-antigenic polysaccharide of Salmonella serological groups C2 and C3. 

The O-antigen polysaccharides of Salmonella serogroups A, B, and D are closely related chemically and immunochemically and consist of a branched tetrasaccharide of the following structure [189] ... 

Biosynthesis of the Salmonella O-Antigen Outer Capsular Polysaccharide... 

An interesting aspect of the biosynthesis of the O-antigen polysaccharide is that different nucleotide triphosphates are the activating agents for each of the monosaccharide residues in the repeating unit. The reaction of UDP-Gal with bactoprenol phosphate is the first reaction in the process, followed by reactions with TDP-Rha, GDP-Man, and CDP-Abe as shown for the biosynthesis of Salmonella typhimurium O-antigen polysaccharide summarized in Fig. 10.12A. 

Figure 10.12. Biosynthetic reactions for the formation of (A) Salmonella typhimurlum O-antigen polysaccharide, and (B) mechanism for the biosynthesis of glycerol teichoic acid. Bpr, bactoprenol.

V. Salmonella O-antigen synthase elongates the 0-antigen polysaccharide by transferring a tetrasaccharide from bactoprenol pyrophosphate tetrasaccharide... 

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.

In 1967, two possible general mechanisms for the biosynthesis of linear polysaccharides were proposed.86 The first was the primer mechanism already discussed, and the second was the sequential addition of monomer units to the reducing end by the insertion between a carrier and the growing polysaccharide chain. This latter mechanism had been shown for Salmonella sp. O-antigenic polysaccharide87 then in 1973, it was shown for the bacterial cell-wall polysaccharide murein88 in which the carrier was a polyisoprenoid pyrophosphate. 

The descriptive phase of biology is an essential prerequisite for the healthy growth of biochemistry, and the serological classification of the Salmonellas and related Enterobacteria has allowed a comprehensive and reproducible series of analyses to be made where otherwise a chaotic situation could have arisen. The Kauffmann-White Schema embraces more than the specificities due to polysaccharides of the O antigens. The H antigens, for example, are specificities due to the protein components of the flagella, and these are probably beyond the scope of chemical methods available at this time. 

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