The Pseudomonas aeruginosa PsrA responds to long-chain fatty acid signals to regulate the fadBA5 β-oxidation operon

• DOI: 10.1099/mic.0.2008/018135-0
• Publication Date: 2008-06-04T22:11:12Z
• Authors: Yun Kang; David T. Nguyen; Mike S. Son; Tung T. Hoang
• Keywords: Transposon mutagenesis; Insertional mutagenesis

β-Oxidative enzymes for fatty acid degradation (Fad) of long-chain acids (LCFAs) are induced in vivo during lung infection cystic fibrosis patients, and this may contribute to nutrient acquisition pathogenesis Pseudomonas aeruginosa. The promoter region one P. aeruginosa β-oxidation operon, fadBA5 (PA3014 PA3013), was mapped. Focusing on the transposon mutagenesis strain PAO1 carrying P fadBA5–lacZ fusion, a regulator operon identified be PsrA (PA3006). Transcriptome analysis ΔpsrA mutant indicated its importance regulating β-oxidative enzymes. These microarray data were confirmed by real-time RT-PCR analyses fadB5 lipA (encoding lipase) genes. Induction demonstrated respond novel LCFA signals, induction required presence PsrA, suggesting that LCFAs bind derepress fadBA5. Electrophoretic mobility shift assays indicate specific binding region. This is disrupted (C18 : 1 Δ9, C16 0, C14 0 and, lesser extent, C12 0), but not other medium- or short-chain first intermediate β-oxidation, acyl-CoA. It shown here binds responds signals