Prevention of penicillin-induced lysis of Staphylococcus aureus by cellular lipoteichoic acid.

The lysis of Staphylococcus aureus FDA 209P induced by benzylpenicillin was completely inhibited by cellular lipoteichoic acid isolated from an homologous organism. The cells prevented from penicillin-induced lysis were in static state and did not lose viability. The lipoteichoic acid inhibited either extracellular autolysin activity in culture supernatant or autolysis of whole cells in exponential phase of S. aureus. These results indicate that the prevention of penicillin-induced lysis of S. aureus by the lipoteichoic acid was brought about by the inhibition of autolytic activity of the organism.