Pleiotropy of p -fluorophenylalanine-resistant and antibiotic hypersensitive mutants of Pseudomonas aeruginosa

SUMMARY Mutants of Pseudomonas aeruginosa isolated as being resistant to p -fluorophenylalanine (FPA-r) are pleiotropic, showing patterns of phenotypic alteration of host-controlled modification, growth rate at 37 and 43 °C, ability to grow on minimal medium, response to antibiotics and ribosomal characteristics. Alterations in host-controlled modification are also found in FPA-r mutants of Escherichia coli B. The pleiotropy arising in these FPA-r mutants of P. aeruginosa appears to result from alterations in the specificity of protein synthesis. Phenotypic variations in host-controlled modification of the type found in the FPA-r mutants may provide a method for the detection of suppressor mutations which act by miscoding.