Influence of the regulatory protein RsmA on cellular functions in Pseudomonas aeruginosa PAO1, as revealed by transcriptome analysis

• Published in: Microbiology (Society for General Microbiology) Vol. 152; no. 2; pp. 405 - 418
• Main Authors: Burrowes, Elizabeth, Baysse, Christine, Adams, Claire, O'Gara, Fergal
• Format: Journal Article
• Language: English
• Published: England Soc General Microbiol 01.02.2006
• Subjects: 4-Butyrolactone - analogs & derivatives; 4-Butyrolactone - metabolism; Gene Expression Regulation, Bacterial; Genes, Bacterial; Proteome - analysis; Pseudomonas aeruginosa; Pseudomonas aeruginosa - genetics; Pseudomonas aeruginosa - physiology; Transcription, Genetic
• ISSN: 1350-0872; 1465-2080
• DOI: 10.1099/mic.0.28324-0

BIOMERIT Research Centre, Department of Microbiology, National University of Ireland, Cork, Ireland Correspondence Fergal O'Gara f.ogara{at}ucc.ie RsmA is a posttranscriptional regulatory protein in Pseudomonas aeruginosa that works in tandem with a small non-coding regulatory RNA molecule, RsmB (RsmZ), to regulate the expression of several virulence-related genes, including the N -acyl-homoserine lactone synthase genes lasI and rhlI , and the hydrogen cyanide and rhamnolipid biosynthetic operons. Although these targets of direct RsmA regulation have been identified, the full impact of RsmA on cellular activities is not as yet understood. To address this issue the transcriptome profiles of P. aeruginosa PAO1 and an isogenic rsmA mutant were compared. Loss of RsmA altered the expression of genes involved in a variety of pathways and systems important for virulence, including iron acquisition, biosynthesis of the Pseudomonas quinolone signal (PQS), the formation of multidrug efflux pumps, and motility. Not all of these effects can be explained through the established regulatory roles of RsmA. This study thus provides both a first step towards the identification of further genes under RsmA posttranscriptional control in P. aeruginosa and a fuller understanding of the broader impact of RsmA on cellular functions. Abbreviations: AHL, N -acyl homoserine lactone; C4-HSL, N -butanoyl- L -homoserine lactone; 3-oxo-C12-HSL, N -(3-oxododecanoyl)- L -homoserine lactone; PQS, Pseudomonas quinolone signal; QS, quorum sensing Genes with a statistically significant ( P =0·05), minimum twofold change in expression in the rsmA mutant compared to P. aeruginosa PAO1 wild-type are shown in Supplementary Table S1, genes commonly altered in expression in the P. aeruginosa PAK vfr mutant and the P. aeruginosa PAO1 rsmA mutant are shown in Supplementary Table S2, and genes commonly altered in expression in the P. aeruginosa PAK retS mutant and the P. aeruginosa PAO1 rsmA mutant are shown in Supplementary Table S3, available with the online version of this paper.