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Staphylococcus aureus cell surface: capsule as a barrier to bacteriophage adsorption
Infection and Immunity
|February 1, 1979
Summary
Bacterial capsules hinder phage binding. Encapsulated Staphylococcus aureus showed reduced phage adsorption compared to unencapsulated strains, suggesting capsules act as a barrier and impact phage typing efficacy.
Area of Science:
- Microbiology
- Bacteriology
- Virology
Background:
- Staphylococcus aureus is a significant human pathogen.
- Bacteriophages are viruses that infect bacteria and are used in phage typing for bacterial identification.
- Bacterial capsules can influence host-pathogen interactions and susceptibility to antimicrobial agents.
Purpose of the Study:
- To investigate the effect of encapsulation on bacteriophage binding to Staphylococcus aureus.
- To determine if bacterial capsules act as a barrier to phage adsorption.
- To explore the implications of reduced phage binding for Staphylococcus aureus phage typing.
Main Methods:
- Comparison of phage adsorption efficiency between encapsulated and unencapsulated Staphylococcus aureus strains (M and Smith variants).
- Utilized specific bacteriophages (84 and 52A) for adsorption assays.
- Proposed mechanism involving capsule acting as a physical barrier to phage receptors.
Main Results:
- Encapsulated Staphylococcus aureus strains (M and Smith) exhibited significantly less efficient binding of phages 84 and 52A compared to their unencapsulated counterparts (M variant and Smith compact).
- The bacterial capsule appears to impede phage access to cell wall receptors (peptidoglycan and teichoic acid).
Conclusions:
- The bacterial capsule of Staphylococcus aureus functions as a barrier, reducing phage adsorption efficiency.
- Inefficient phage adsorption by encapsulated strains may contribute to difficulties in accurate phage typing of these bacteria.
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