Related Experiment Videos
Changes in phage-sensitivity of Shigella flexneri strains. II. The F-like character of Ms2-sensitive variants
Abstract:
Variants sensitive to male specific phage Ms2 appeared among Ms2 non-sensitive Shigella flexneri cultures in the course of liquid medium passages. Sensitivity to Ms2 was lost on acridine orange treatment and was transferable into Ms2 non-sensitive variants. The Ms2 sensitive variants had fimbrial antigen. Electron microscopy showed that Ms2 phages were adsorbed on the F-like fimbriae of these variants. It was assumed that F-like plasmids determining F-like fimbrial antigen were carried by these variants.
Insights
Shigella flexneri variants sensitive to male-specific phage MS2 emerged during passage. This MS2 phage sensitivity was linked to F-like fimbriae and transferable, suggesting plasmid involvement in phage interaction.
Area of Science:
- Microbiology
- Bacteriology
- Virology
Background:
- Shigella flexneri is a bacterial pathogen.
- Bacteriophages are viruses that infect bacteria.
- Phage-host interactions are crucial in microbial evolution.
Purpose of the Study:
- To investigate the emergence of phage sensitivity in Shigella flexneri.
- To understand the mechanism behind MS2 phage sensitivity.
- To explore the role of fimbriae and plasmids in phage susceptibility.
Main Methods:
- Serial passage of Shigella flexneri in liquid medium.
- Acridine orange treatment to assess curing of sensitivity.
- Electron microscopy to visualize phage-bacterial interactions.
- Characterization of fimbrial antigens.
Main Results:
- MS2-sensitive variants of Shigella flexneri appeared after serial passage.
- Sensitivity to MS2 phage was lost after acridine orange treatment.
- Sensitivity was transferable to MS2 non-sensitive variants.
- MS2-sensitive variants possessed F-like fimbriae, with MS2 phages adsorbing to them.
Conclusions:
- The emergence of MS2 sensitivity in Shigella flexneri is associated with F-like fimbriae.
- Acridine orange treatment suggests a plasmid-mediated mechanism for MS2 sensitivity.
- F-like plasmids likely determine the F-like fimbrial antigen and MS2 phage adsorption.