Abstract
The biosynthesis of teichoic acid in cell suspensions of 2 strains of Staphylococcus aureus is partially inhibited by the same low concentrations of penicillin that inhibit mucopeptide synthesis by 90-100%. Further increase in the concentration of the antibiotic by several hundred-fold does not cause any greater inhibition of teichoic acid synthesis. Other conditions, such as amino-acid deficiency or the presence of cycloserine or 5-fluorouracil, that inhibit mucopeptide synthesis also inhibit teichoic acid formation. The degree of inhibition of teichoic acid synthesis caused by relatively high concentrations (10 [mu]g/ml) of benzylpenicillin depends critically on the age of the culture from which the cell suspensions were prepared. No significant amounts of soluble teichoic acid were found in the fluid from cells incubated in the presence of penicillin. A high proportion of the teichoic acid formed in the presence of penicillin can be removed from wall preparations at room temperature by 0-1[image]-NH2. This is not true of the teichoic acid formed in the absence of penicillin. The teichoic acid extracted with NH3 from preparations of cell walls made from cells treated with penicillin is excluded from Sephadex G-25, has a low molar ratio of glucosamine to phosphorus and contains muramic acid, alanine, glutamic acid, glycine and lysine. The implications of these results for the mechanism of action of penicillin are discussed.