STUDIES ON THE ANTIGENIC STRUCTURE OF THE 80/81 COMPLEX OF STAPHYLOCOCCUS AUREUS

Study of Staphylococcus aureus teichoic acid immunodominant site by help of synthetic haptens

The beta ribitol teichoic acid was extracted and purified from Staphylococcus aureus strain Wood 46 and chemically and immunologically characterised. Rabbit antiserum was prepared against formalin killed Staphylococcus aureus cells. Liquid phase immunoprecipitation of the beta ribitol teichoic acid-anti-Staphylococcus aureus serum system was studied by laser nephelometry. Various mono- and disaccharides (N-acetyl-glucosamine-ribitol with alpha- or beta-linkage and N-acetyl-glucosamine-ribitol-phosphate with beta-linkage) were prepared by organic synthesis, reproducing part of the ribitol teichoic acid molecule. Inhibition by those mono- or disaccharides of the precipitation of the beta-ribitol teichoic acid-Staphylococcus aureus antibodies system was studied quantitatively by determining inhibitory ratio of each inhibitor. Glucose, ribitol and glucosamine were weak inhibitors whereas N-acetyl-glucosamine was a better one, stronger than disaccharide with an alpha-linkage. The beta linked disaccharide and beta-methyl-N-acetyl-glucosamine gave comparable inhibition and both compounds were effective inhibitors. The most potent inhibitor was phosphorylated beta-linked disaccharide which inhibited 25% more than the same disaccharide without phosphorus. Thus, the function of phosphorus in Staphylococcus aureus beta ribitol teichoic acid recognition by antibodies was demonstrated.

Chemical and biochemical studies for the differentiation of coagulase-positive staphylococci

The cell wall composition, the configuration of lactic acid produced from glucose under anaerobic conditions, the occurrence of fructose-1,6-diphosphate (FDP) activated L-lactate dehydrogenase (L-LDH), and the esterase pattern were determined from more than 80 strains of coagulase-positive staphylococci isolated from man and animal. Strains isolated from man, swine, bovines and hares form a rather homogeneous group. They exhibit a similar cell wall composition, produce predominantly D,L-lactate and have a characteristic and simple esterase pattern. Coagulase-positive staphylococci isolated from dogs, horses, minks and pigeons are quite distinct from typical Staphylococcus aureus strains. They exhibit a different cell wall composition, produce only L-lactate, possess an L-LDH which is specifically activated by FDP, and have a quite complex esterase pattern.

Studies on polysaccharide C of Staphylococcus epidermidis. 1. Isolation and chemical characterization

Polysaccharide C (poly C) has been isolated from two strains of S. epidermidis and characterized chemically. The results suggest that poly C is a wall N-acetylglucosaminylglycerol teichoic acid, linked through 1:3-phosphodiester linkages. One poly C preparation contained only beta-linked N-acetyglucosamine, the other traces of alpha-linked sugar in addition. The degree of substitution of sugar in the poly C preparations from the two strains was about 50 and 25 per cent.

Immunological properties of teichoic acids

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Serological activity of staphylococcal polysaccharide

The polysaccharide from cell walls of coagulase-positive staphylococci coated both latex particles and tanned red cells for agglutination by human sera and by specific staphylococcal antisera. Treatment with trypsin or autoclaving destroyed the capacity of polysaccharide to coat particles but did not affect precipitation of antibody. Periodic acid destroyed both properties. The teichoic acid portion of the staphylococcal polysaccharide displayed precipitin activity similar to polysaccharide, but it did not coat either latex particles or tanned red cells. Teichoic acid did, however, inhibit specific agglutination of polysaccharide-coated particles or cells.