Related Experiment Video
Updated: Aug 7, 2026

Stress-induced Antibiotic Susceptibility Testing on a Chip
Published on: January 8, 2014
Evidence for participation of autolysins in bactericidal action of oxacillin on Staphylococcus aureus
Abstract:
A comparison of the autolytic enzyme activity in Staphylococcus aureus strains that differ markedly in their rates of lysis and killing after exposure to oxacillin has been made. Log-phase cells of the clinical isolate that is tolerant to oxacillin inhibition were found to contain a level of autolytic enzyme activity comparable to that in a sensitive strain. This autolysin from log-phase cells was recovered after a single freeze-thaw cycle and assayed by using both native and penicillin (un-cross-linked) mureins. These same assays, however, revealed a significant difference in autolysin activity extractable from the two strains if the cells were inhibited by oxacillin. Under these conditions, the S. aureus strain that is susceptible to the killing and lytic effects of oxacillin had considerably more activity on penicillin murein than did the tolerant organism. These results provide evidence that hydrolytic enzymes on the cell surface are required to augment the wall damage initiated by oxacillin and other beta-lactam antibotics to produce a bactericidal effect.
More Related Videos
Related Concept Videos
Antimicrobial Effectiveness
Staphylococcal Skin Infections
Mechanism of Antibiotic Resistance in MRSA
Inhibitors of Gram-positive Cell Wall Synthesis
Inhibitors of Bacterial Protein Synthesis
Clinical Significance of Antibiotic Resistance

