Cell fusion between L-forms and protoplasts of Staphylococcus aureus

Area of Science:

• Microbiology
• Bacterial genetics
• Cell fusion

Background:

• Staphylococcus aureus exhibits resistance to multiple antibiotics, posing a significant challenge in clinical settings.
• Bacterial cell fusion techniques are crucial for genetic manipulation and understanding resistance mechanisms.

Purpose of the Study:

• To investigate the development of doubly drug-resistant fusion products (fusants) between Lysostaphin protoplasts and stable L-forms of Staphylococcus aureus.
• To determine the efficiency and characteristics of fusion products generated using polyethylene glycol (PEG) treatment.

Main Methods:

• Protoplasts and L-forms of Staphylococcus aureus with distinct drug resistance markers were treated with PEG.
• Two methods involving different enrichment and culturing strategies (using NaCl-BHI broth and reversion medium) were employed to recover doubly resistant fusants.
• Analysis of fusant colonial morphology (L-form, coccal, or mixed) was performed on various assay media.

Main Results:

• Doubly resistant fusants were successfully generated, primarily exhibiting L-form morphology when plasmid-mediated resistance was involved.
• The method utilizing enrichment on reversion medium (R medium) influenced the resulting fusant morphology, yielding coccal-type cells.
• Fusion between protoplasts and L-forms primarily resulted in the transfer of plasmid-controlled drug resistance, unlike fusions between protoplasts or L-forms alone.

Conclusions:

• Polyethylene glycol (PEG)-induced cell fusion is an effective method for generating drug-resistant Staphylococcus aureus fusants.
• The study highlights the successful transfer of plasmid-mediated drug resistance during protoplast-L-form fusion.
• The choice of recovery and culturing methods significantly impacts the morphology of the resulting fusants.