Transcriptome analysis of Pseudomonas aeruginosa PAO1 WT, ΔpauA2 mutant, and ΔpauA2 suppressor. Pseudomonas aeruginosa PAO1

PauA2 plays an essential role in spermine catabolism and that exogenous spermine exerts a bactericidal effect on the ΔpauA2 mutant of P. aeruginosa. Not only subjected to growth inhibition by spermine, the pauA2 mutant without a functional γ-glutamylpolyamine synthetase PauA2 became more sensitive to β-lactam antibiotics in human serum. To explore PauA2 as a potential target of drug development, suppressors of the pauA2 mutant were isolated from selection plates containing spermine. These suppressors share common changes in various phenotypes. Genome resequencing of a representative suppressor revealed a unique mutation at the phoU gene, and a constitutive expression of the Pho regulon as evidenced by measurements of transcriptome analysis. Overall design: We conducted two independent microarray experiments for each of strains. P. aeruginosa PAO1 and its derivatives was grown aerobically in LB broth along with 300 rpm shaking at 37°C.