Teichoic acids from Staphylococcus aureus

All of the ribitol teichoic acids so far examined are composed of chains of ribitol residues joined through phosphodiester groups at C-l and C-5. Each chain is terminated by a phosphomonoester residue, and the ribitol residues bear glycosyl and D-alanine ester substituents. Detailed structures have been proposed for the polymers from Bacillus aubtilis and Lactobacillus arabinosus, and from two strains of Staphylococcus aureus. The structure of the teichoic acid from Bacillus subtilis was the first to be established in detail the other polymers differ mainly in the nature of the glycosyl substituents. 

Reeder and Eckstedt389 studied the interaction of con A with teichoic acids from Staphylococcus aureus and Staphylococcus epidermidis by gel diffusion, and precipitation in a fluid system. The teichoic acid from strain Tj of S. epidermidis contains a-D-glucopyranosyl residues, and it precipitated with con A, whereas strain T2, which is /3-D-glucosylated, did not. Classical precipitin curves resulted when con A interacted with strains T2 and 412 (also a-D-glucosylated) the precipitation was specifically inhibited by D-glucose, 2-acetamido-2-deoxy-D-glucose, and methyl a- and /3-D-glucopyranosides.389... 

Particulate preparations of Staphylococcus aureus (Copenhagen) catalyze the transfer of 2-acetamido-2-deoxy-D-glucosyl residues from the uridine pyrophosphate derivative to teichoic acid from which n-alanine residues and 2-acetamido-2-deoxy-D-glucosyl residues have been removed. Intact teichoic acid is inert as a precursor. The ratio of a-n- to /3-n-linkages in the product synthesized by an unfractionated enzyme was 85 to 15. 

Studies of the effects of thermal stress on three strains of Staphylococcus aureus have indicated that the teichoic acid in the cell walls aids the survival of the cells by maintaining the accessible pool of Mg ions on the cell surface. A spore-forming Gram-negative bacterium with properties closely similar to those of Bacillus circulans, and which hydrolyses the 2-acetamido-2-deoxy-D-glucosylribitol teichoic acid from Staph, aureus, has been isolated from soil. The immunogenicities of teichoic and lipoteichoic acids from the cell walls and plasma membranes of several oral bacteria that produce lactic acid have been reported. 

The ribitol teichoic acid from the cell walls of Staphylococcus aureus in solution binds Mg + ions univalently to phosphate groups and to a counter-ion, in contrast to the cell wall where Mg + ions form bridges across phosphate groups of adjacent chains of teichoic acid. Differences in the affinities between cell walls with or without alanyl ester residues were much greater at low concentrations than they were at high concentrations of Mg + ions. Thus, at very low concentrations of Mg + ions, effective binding to the cell wall is significantly improved... 

Poly(ribitol phosphate) synthetase has been found in particulate fractions from Staphylococcus aureus H, and Lactobacillus plantatrum.lt ll-m The bulk of the activity in Lactobacillus plantarum was in crude, cell-wall preparations, and the enzyme is apparently located in the membrane, although intimate association with the wall itself has been suggested. Unlike the natural teichoic acid, the enzymically synthesized ribitol phosphate polymer was readily extracted with phenol hydrolysis by acid and by alkali gave the expected products, and oxidation with periodate indicated a chain length of 5-9 units, a value which compares well with that of 8 units for the natural polymer in the walls of this organism. 

Extracts prepared from whole cells of all such organisms contained a glyceritol phosphate polymer, even when no such polymer was present in the walls. This finding is in accordance with a previous report by Mitchell and Moyle that the cell envelope and the small particle fraction from Staphylococcus aureus contain a glyceritol phosphate. This observation could explain why Lactobacillus arabinosus contains cytidine glyceritol pyrophosphate (and not the corresponding teichoic acid) in the cell wall. 

Teichoic acids of different strains of Staphylococcus aureus differ in the relative proportion of a- and /3- forms of the 2-acetamido-2-deoxy-n-glucosyl residues. For example, these glycosyl residues are essentially all 3-D-linked in strains H and Duncan, whereas those of strain 3528 are a-D-linked. Enzyme preparations from these bacteria catalyze the formation of the linkage typical of the isolated teichoic acid of the particular strain. 

Investigation of the cell-wall composition and associated properties of strains of Staphylococcus aureus, which are resistant to methicillin, has not revealed evidence for any unusual wall polymers/ The ribitol teichoic acid isolated from Staphylococcus hyicus contains 2-acetamido-2-deoxy-D-glucosyl residues. Interaction of the teichoic acid with concanavalin A, and its susceptibility to 0C-, but not to 3-D-2-acetamido-2-deoxyglucosidase, showed that the amino-sugar is in the a-configuration. 

Plant estrogens and metabolites of these compounds that have been excreted by animals have been fractionated on dextran gel columns (Nilsson, 1962). Gel filtration has been used in an investigation of polyphenols from brewery wort (Woof, 1962). The catecholamines adrenalin and noradrenalin can be separated from plasma proteins on Sephadex (Marshall, 1963). Various constituents of Staphylococcus aureus have been separated on Sephadex, namely, teichoic acid, D-alanine, N-acetylglucos-amine, and N-acetylglucosaminylribitol (Sanderson et al., 1962). 

It is possible that some components of the lipoteichoic acid fraction are primers for the synthesis of wall teichoic acid, and are themselves constructed by rather different mechanisms from those above. There is evidence that phosphatidylglycerol in the cell membrane of Staphylococcus aureus can act as a precursor of glycerol in a form of lipoteichoic acid and that this can act as an acceptor for the construction of wall-type teichoic acid (Glaser and Lindsay, 1974). There is also good evidence to suggest that... 

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