Related Experiment Video
Updated: Aug 16, 2025
Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
Published on: May 8, 2013
Isolation, characterization, and antibacterial activity of lytic bacteriophage against methicillin-resistant
Zeinab Rezaei1, Ameneh Elikaei1, Seyed Mahmoud Barzi2
1Department of Microbiology, Faculty of Biological Sciences, Alzahra University, Tehran, Iran.
Background And Objectives:
Phage therapy has gained interest as an alternative treatment for methicillin-resistant Staphylococcus aureus (MRSA) infections. The purpose of this study was to isolate and characterize an effective bacteriophage against isolates of MRSA.
Materials And Methods:
Bacteriophage was isolated from hospital sewage. Lytic activity and the titers of phage lysates were measured using spot test and double-layer plaque assay. The phage characterization was determined through transmission electron microscopy. Adsorption rate, host range and stability tests were investigated. The latent period and burst size were estimated from a one-step growth curve. The effect of bacteriophage against MRSA biofilms was determined and Real-time PCR was used to assess the effects of the bacteriophage on the expression of the biofilm-associated genes.
Results:
TEM results showed that the phage resembled the Cystoviridae family. Its latent period was 30 min, corresponding to about 71/43 phage particles per infected cell. The phage had a broad host range and it was most stable at 37°C and pH 7. It was sensitive to NaCl concentrations. The expressions of the biofilm-associated genes were significantly reduced in the presence of the phage.
Conclusion:
The isolated phage was effective against MRSA strains and it can be an optional strategy of controlling biofilm development.
Insights
A novel bacteriophage effectively targets methicillin-resistant Staphylococcus aureus (MRSA) and reduces biofilm formation. This phage therapy offers a promising alternative for combating challenging MRSA infections and biofilms.
Area of Science:
- Microbiology
- Molecular Biology
- Infectious Diseases
Background:
- Phage therapy is an emerging alternative for treating infections caused by antibiotic-resistant bacteria.
- Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant public health threat due to its resistance to conventional antibiotics.
Purpose of the Study:
- To isolate and characterize a bacteriophage with potent lytic activity against MRSA.
- To evaluate the efficacy of the isolated bacteriophage in controlling MRSA biofilms.
Main Methods:
- Bacteriophage isolation from hospital sewage.
- Characterization using transmission electron microscopy (TEM), host range, stability, and growth curve analyses.
- Assessment of anti-biofilm activity and impact on biofilm-associated gene expression via Real-time PCR.
Main Results:
- The isolated phage, resembling the Cystoviridae family, exhibited a broad host range and optimal stability at 37°C and pH 7.
- A short latent period (30 min) and significant reduction in biofilm-associated gene expression were observed.
- The phage demonstrated effectiveness against MRSA strains and inhibited MRSA biofilm development.
Conclusions:
- The characterized bacteriophage is effective against MRSA.
- This phage represents a potential therapeutic strategy for managing MRSA infections and controlling biofilm formation.
Related Concept Videos
01:30Lytic Cycle of Bacteriophages
01:31Defense Against Bacterial Pathogens
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...