Related Experiment Video
Updated: Aug 17, 2026

A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
Published on: February 19, 2019
[Impact of Ph-SA on the expression of delta-toxin in Staphylococcus aureus]
Li Guo1, Jie Zhang, Xiao-yan Tang
1Laboratory of Transplant Engineering and Immunology, West China Hospital, Sichuan University, Chengdu 610041, China.
Objective:
We carried out this pilot study in an attempt to observe the effect of Ph-SA on the secretion of delta-toxin in S. aureus ATCC29213.
Methods:
When A595 reaching about 0. 2, the bacteria were divided into three groups and were treated by PBS, penicillin and Ph-SA respectively. The amount of delta-toxin from different groups and growth phases was analyzed by high performance liquid chromatography.
Results:
It was observed that the secretion of delta-toxin in Ph-SA group was less than that in the other two groups at the same time (P < 0.05).
Conclusion:
We postulate that Ph-SA has the negative effect on the activity of agr system, acting as a pseudo-ligand.
Related Concept Videos
Clinical Significance of Antibiotic Resistance
Staphylococcal Skin Infections
Regulation of Bacterial Virulence
Mechanism of Antibiotic Resistance in MRSA
Bacterial Toxins
Other Stress Responses in Bacteria

