Cloning and characterization of a DNA fragment that complements the nfxB mutation in Pseudomonas aeruginosa PAO

The 2.2-kilobase DNA fragment that can complement the nfxB mutation in Pseudomonas aeruginosa PAO was cloned from chromosomal DNA of P. aeruginosa PAO1. The nfxB mutants show an increase in resistance to quinolones and hypersusceptibility to beta-lactam and aminoglycoside antibiotics. In the mutants, a 54 kDa outer membrane protein newly appeared. The phenotype was restored to the wild-type by transformation with plasmid carrying the 2.2-kb DNA fragment.