Characterization of Staphylococcus aureus plasmids introduced by transformation into Bacillus subtilis

Area of Science:

• Molecular Biology
• Microbiology
• Genetics

Background:

• Plasmids are extrachromosomal DNA elements crucial for bacterial adaptation.
• Understanding interspecies plasmid transfer is key to microbial genetics.

Purpose of the Study:

• To introduce and characterize Staphylococcus aureus plasmids in Bacillus subtilis.
• To investigate the replication and genetic transfer capabilities of these plasmids in a new host.

Main Methods:

• Transformation and transduction of bacterial strains.
• Plasmid DNA isolation and characterization.
• Restriction endonuclease mapping.
• Molecular weight estimation.

Main Results:

• Four Staphylococcus aureus plasmids (pUB110, pCM194, pSA2100, pSA0501) were successfully introduced into Bacillus subtilis.
• These plasmids replicated as multicopy autonomous replicons in both Rec+ and Rec- B. subtilis strains.
• High transformation frequencies (10^4-10^5 transformants/µg DNA) were achieved.
• Restriction maps were generated, and molecular weights were estimated.
• Evidence suggests pSA2100 arose from a fusion of pSA0501 and pCM194.

Conclusions:

• Staphylococcus aureus plasmids can function and replicate autonomously in Bacillus subtilis.
• The study provides detailed molecular characterization of these plasmids.
• Interspecies plasmid transfer and replication are feasible, offering tools for genetic manipulation.