Isolation and characterization of a cryptic plasmid from mesophilic aeromonads: potential as a cloning vector

Area of Science:

• Microbiology
• Molecular Biology
• Genetics

Background:

• Aeromonas species are opportunistic pathogens.
• Plasmids are extrachromosomal DNA elements that can carry beneficial genes.
• Characterizing plasmids is crucial for understanding bacterial adaptation and for biotechnological applications.

Purpose of the Study:

• To isolate and characterize a plasmid from clinical and environmental Aeromonas sobria and Aeromonas hydrophila isolates.
• To determine if the isolated plasmid confers antimicrobial resistance.
• To evaluate the plasmid's potential as a molecular cloning vector.

Main Methods:

• Isolation of covalently closed circular plasmid DNA.
• Plasmid size determination (2.6 kb).
• Assessment of antimicrobial resistance gene carriage.
• Estimation of plasmid copy number (20-25 copies per chromosome equivalent).
• Identification of unique restriction sites.

Main Results:

• A 2.6 kb plasmid was successfully isolated from Aeromonas isolates.
• The plasmid does not carry genetic determinants for antimicrobial resistance.
• The plasmid exhibits high stability and a moderate copy number.
• Unique restriction sites were identified on the plasmid.

Conclusions:

• The isolated 2.6 kb plasmid from Aeromonas species lacks antimicrobial resistance genes.
• Its stability, small size, and unique restriction sites make it a promising candidate for development as a cloning vector.
• This plasmid could serve as a valuable tool in molecular biology for gene cloning and manipulation in Aeromonas or related bacteria.