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Published on: January 8, 2014
Lysostaphin-induced, osmotically fragile Staphylococcus aureus cells
Journal of Bacteriology
|July 1, 1970
Summary
Lysostaphin treatment of Staphylococcus aureus cells causes osmotic fragility. Complete cell wall removal, requiring 20+ minutes of exposure, eliminates reversion to normal cells and antigenicity.
Area of Science:
- Microbiology
- Cell Biology
- Biochemistry
Background:
- Staphylococcus aureus possesses a complex cell wall essential for its integrity.
- Lysostaphin is a specific enzyme targeting the staphylococcal cell wall.
Purpose of the Study:
- To investigate the effects of lysostaphin on Staphylococcus aureus cell wall integrity.
- To determine the correlation between lysostaphin exposure time, cell wall composition, and cellular functions.
Main Methods:
- Exposure of Staphylococcus aureus cells to varying concentrations and durations of lysostaphin.
- Chemical analysis for cell wall hexosamine content.
- Serological testing using anti-k antiserum.
- Plating on hypertonic sucrose medium to assess cell reversion.
- Manometric studies to evaluate metabolic activity.
Main Results:
- Short lysostaphin exposure (2 min) induced osmotic fragility but retained hexosamine and reversion capability.
- Extended exposure (5-10 min) led to hexosamine loss and loss of reversion ability.
- Complete hexosamine removal and loss of antigenicity (anti-k antiserum reaction) occurred after 20+ min.
- Lysostaphin-induced L-type colonies were rare.
- Metabolic activity of lysostaphin-treated protoplasts was comparable to untreated cells.
Conclusions:
- Lysostaphin effectively degrades the Staphylococcus aureus cell wall in a time-dependent manner.
- Complete cell wall removal is necessary to abolish reversion and antigenicity.
- Metabolic functions are largely preserved even after significant cell wall modification.
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