RNA-seq data of PA3299 in Pseudomonas aeruginosa PAO1

Quorum sensing (QS) is a ubiquitous cell-to-cell communication mechanism in bacteria. Here, we demonstrate that the long-chain fatty acid-CoA ligase FadD1 functions at the top of the QS hierarchy of Pseudomonas aeruginosa, as it controls the transcriptional expression of lasR and the production of QS signals. The significance of this study is the identification of FadD1 as a global transcriptional regulator with a DNA-binding leucine zipper motif to control the expression of various target genes. Intriguingly, another long-chain fatty acid-CoA ligase, FadD2, obtained regulatory activity on the expression of lasR when it was fused with the leucine zipper motif of FadD1. Our study reveals a new list of transcriptional regulators composed of a specific class of fatty acid-CoA ligases with a leucine zipper motif that play a vital role in the physiology and pathogenesis of bacteria.