Relationship between R and FP plasmids in Pseudomonas aeruginosa

Abstract

The plasmid FP110 possessing chromosome mobilizing ability for Pseudomonas aeruginosa but carrying no determinants for antibiotic resistance, is found to be related by incompatibility, entry exclusion, and other criteria to the independently isolated R plasmids R18-1 and R56Be which carry resistance determinants for carbenicillin. The frequency of FP plasmid appearance in clinical isolates of P. aeruginosa suggests the possibility that they may be a source of R plasmids in this bacterium.