Genetic mapping and characterization of Pseudomonas aeruginosa mutants that hyperproduce exoproteins

Abstract

We isolated two mutants of Pseudomonas aeruginosa PAO with defective iron uptake. In contrast to the wild-type strain, the mutants produced extracellular protease actity in media containing high concentrations of salts or iron and hyperproduced elastase, staphylolytic enzyme, and exotoxin A in ordinary media (Xch mutants). The mutations were located in the 55' region of the chromosome, between the markers met-9011 and pyrD.

Proteinases of psychrotrophic bacteria: their production, properties, effects and control

“…They suggested that previous reports of inhibition by ammonium ions represented a non-specific effect, most likely related to the high ionic strength of the medium. Recent work supports their conclusions (Fairbairn, 1984;Bjorklind et al 1985).…”