Related Experiment Video
Updated: Aug 11, 2026

The Use of a β-lactamase-based Conductimetric Biosensor Assay to Detect Biomolecular Interactions
Published on: February 1, 2018
[Role of Ph-SA in enhancing bactericidal activity of beta-lactam antibiotics]
Xiao-yan Tang1, Jie Zhang, Li Guo
1Key Laboratory of Transplant Engineering and Immunology, the Ministry of Health, West China Hospital, Sichuan University, Chengdu 610041, China.
Objective:
To identify the role of Ph-SA in inhibiting beta-lactamase secretion of S. aureus and in enhancing the bactericidal activity of antibiotics against antibiotic resistant bacteria.
Methods:
To determine the effects of Ph-SA on beta-lactamase product of bacteria and on bactericidal activity of penicillin, the growth rate and lactamase activity of penicillin-resistant S. aureus cells in exponential growth were detected after treatment with 1.43 X 10(-4) micromol/mL (10 microg/mL) Ph-SA (Group 1), 2.81 x 10(-2) micromol/mL (10 microg/mL) penicillin (Group 2), 0.715 x 10(-4) micromol/mL(5 microg/mL) Ph-SA + 1.40 x 10(-2) micromol/mL (5 microg/mL) penicillin (Group 3) respectively; and a control group was detected for comparison. The same method was used to detect whether Ph-SA could enhance bactericidal activity of Cefazolin. Results It was revealed that 1.43 x 10(-4) micromol/mL (10 microg/mL) Ph-SA could inhibit beta-lactamase activity significantly, whereas no marked bactericidal activity was detected. The growth rate of bacteria cells treated with 0.715 x 10(-4) micromol/mL Ph-SA + 1.40 x 10(-2) mol/mL penicillin and that of bacteria cells treated with 0. 715 x 10(-4) micromol/mL (5 microg/mL) Ph-SA + 1.05 x 10(-2) micromol/mL (5 microg/mL) Cefazolin were the same as those treated by 2.81 x 10(-)2 micromol/mL (10 microg/mL)penicillin and 2.10 x 10(-2) micromol/mL (10 microg/mL) Cefazolin respectively, while the beta-lactamase activities of both groups were lower than control.
Conclusion:
Ph-SA may be of value in enhancing the bactericidal activity of antibiotics and in alleviating the resistance of bacteria by inhibition of beta-lactamase activity.
Related Concept Videos
Inhibitors of Gram-positive Cell Wall Synthesis
Clinical Significance of Antibiotic Resistance
Mechanism of Antibiotic Resistance in MRSA
Pharmacokinetic–Pharmacodynamic Relationship: Influence of Elimination Half-Life on Effect Duration
Lytic Cycle of Bacteriophages
Inhibitors of Bacterial Protein Synthesis
