[Conjugative R plasmids isolated from hospital strains of Pseudomonas aeruginosa]

Area of Science:

• Microbiology
• Molecular Biology
• Genetics

Background:

• Pseudomonas aeruginosa is a significant nosocomial pathogen.
• Antibiotic resistance in hospital-acquired infections is a growing concern.
• R plasmids are key vectors for the spread of antibiotic resistance.

Purpose of the Study:

• To investigate the presence and characteristics of R plasmids in Pseudomonas aeruginosa hospital strains.
• To determine the antibiotic resistance profiles conferred by these plasmids.
• To analyze the molecular features of identified R plasmids.

Main Methods:

• Isolation and characterization of Pseudomonas aeruginosa strains from patients and the hospital environment.
• Plasmid DNA isolation and analysis.
• Restriction enzyme digestion to map plasmid DNA.
• Determination of plasmid incompatibility groups.

Main Results:

• Conjugative R plasmids, designated pM15 and pM19, were identified in Pseudomonas aeruginosa strains.
• Plasmid pM15 conferred resistance to carbenicillin, kanamycin, and tetracycline.
• Plasmid pM19 conferred resistance to carbenicillin, kanamycin, tetracycline, chloramphenicol, gentamicin, and streptomycin.
• Plasmid pM15 has a molecular weight of 45.8 MD and belongs to the Inc-P1 incompatibility group.

Conclusions:

• Pseudomonas aeruginosa hospital strains harbor conjugative R plasmids.
• These plasmids contribute to multidrug resistance in this opportunistic pathogen.
• The characterization of these plasmids provides insights into their genetic makeup and spread mechanisms.