title: Regulation of Motility and Phenazine Pigment Production by FliA Is Cyclic-di-GMP Dependent in Pseudomonas aeruginosa PAO1.
abstract: The transcription factor FliA, also called sigma 28, is a major regulator of bacterial flagellar biosynthesis genes. Growing evidence suggest that in addition to motility, FliA is involved in controlling numerous bacterial behaviors, even though the underlying regulatory mechanism remains unclear. By using a transcriptional fusion to gfp that responds to cyclic (c)-di-GMP, this study revealed a higher c-di-GMP concentration in the fliA deletion mutant of Pseudomonas aeruginosa than in its wild-type strain PAO1. A comparative analysis of transcriptome profiles of P. aeruginosa PAO1 and its fliA deletion mutant revealed an altered expression of several c-di-GMP-modulating enzyme-encoding genes in the fliA deletion mutant. Moreover, the downregulation of PA4367 (bifA), a Glu-Ala-Leu motif-containing phosphodiesterase, in the fliA deletion mutant was confirmed using the β-glucuronidase reporter gene assay. FliA also altered pyocyanin and pyorubin production by modulating the c-di-GMP concentration. Complementing the fliA mutant strain with bifA restored the motility defect and pigment overproduction of the fliA mutant. Our results indicate that in addition to regulating flagellar gene transcription, FliA can modulate the c-di-GMP concentration to regulate the swarming motility and phenazine pigment production in P. aeruginosa.
authors.affiliation: Institute of Molecular Medicine, National Tsing Hua University, Hsin Chu, Taiwan.
authors.forename: Yi-Ling
authors.initials: YL
authors.lastname: Lo
authors.affiliation: Institute of Molecular Medicine, National Tsing Hua University, Hsin Chu, Taiwan.
authors.forename: Lunda
authors.initials: L
authors.lastname: Shen
authors.affiliation: Institute of Molecular Medicine, National Tsing Hua University, Hsin Chu, Taiwan.
authors.forename: Chih-Hsuan
authors.initials: CH
authors.lastname: Chang
authors.affiliation: Institute of Molecular Medicine, National Tsing Hua University, Hsin Chu, Taiwan.
authors.forename: Manish
authors.initials: M
authors.lastname: Bhuwan
authors.affiliation: Molecular Infectious Disease Research Center, Division of Pediatric Infectious Diseases, Department of Pediatrics, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Cheng-Hsun
authors.initials: CH
authors.lastname: Chiu
authors.affiliation: Institute of Molecular Medicine, National Tsing Hua University, Hsin Chu, Taiwan.
authors.forename: Hwan-You
authors.initials: HY
authors.lastname: Chang
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D001483:Base Sequence; D019295:Computational Biology / Q000379:methods; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000378:metabolism; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D017930:Genes, Reporter; D009154:Mutation; D010619:Phenazines / Q000378:metabolism*; D010860:Pigments, Biological / Q000096:biosynthesis*; D011401:Promoter Regions, Genetic; D011550:Pseudomonas aeruginosa / Q000502:physiology*; D012808:Sigma Factor / Q000235:genetics* / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; C064971:FliA protein, Bacteria; D010619:Phenazines; D010860:Pigments, Biological; D012808:Sigma Factor; C062025:bis(3',5')-cyclic diguanylic acid; D006152:Cyclic GMP