Related Experiment Video
Updated: Aug 5, 2026
12:27
Quantifying the Cytotoxicity of Staphylococcus aureus Against Human Polymorphonuclear Leukocytes
Published on: January 3, 2020
Proline Potentiates Aminoglycoside Bactericidal Efficacy Against Staphylococcus aureus
Bo-Hao Li1,2, Rui-Hua Xu1,2, Zulifukeer Maituersong1,2
1Department of Immunology and Microbiology & Institute of Medical Microbiology, College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
Life (Basel, Switzerland)
|July 28, 2026
Summary
This study found that adding proline to amikacin boosts its ability to kill Staphylococcus aureus, including resistant strains. This combination offers a new approach for treating infections in aquaculture and healthcare settings.
Area of Science:
- Microbiology
- Antimicrobial Resistance
- Aquaculture Pathology
Background:
- Staphylococcus aureus is an emerging zoonotic pathogen in aquaculture, causing significant disease.
- Increasing antimicrobial resistance necessitates novel therapeutic strategies against S. aureus.
Purpose of the Study:
- To identify compounds that enhance antibiotic efficacy against S. aureus.
- To investigate the synergistic effect of proline with aminoglycoside antibiotics.
Main Methods:
- Screening of 20 amino acids for synergistic effects with amikacin against S. aureus.
- Testing the combination against methicillin-resistant S. aureus (MRSA) USA300.
- Evaluating eradication of persisters and biofilms.
- Elucidating the underlying bactericidal mechanisms.
Main Results:
- Exogenous proline significantly potentiates amikacin's bactericidal activity against S. aureus.
- The synergistic effect is observed with other aminoglycosides (neomycin, gentamicin) and against MRSA USA300.
- Proline enhances antibiotic uptake by increasing proton motive force and amplifies oxidative stress by inhibiting ROS-scavenging enzymes and activating the Fenton reaction.
Conclusions:
- Proline combined with amikacin represents a promising strategy to combat S. aureus infections.
- This approach is effective against drug-resistant strains and biofilms.
- The mechanism involves enhanced antibiotic uptake and amplified oxidative stress, leading to bacterial cell death.
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