Identification of a new gene PA5017 involved in flagella-mediated motility, chemotaxis and biofilm formation in Pseudomonas aeruginosa

University of Helsinki, Helsinki, Uusimaa, Finland
FEMS Microbiology Letters (Impact Factor: 2.12). 08/2007; 272(2):188-95. DOI: 10.1111/j.1574-6968.2007.00753.x
Source: PubMed


Flagella-mediated motility is recognized as one of the major factors contributing to virulence in Pseudomonas aeruginosa. During a screening of a mini-Mu transposon mutant library of P. aeruginosa PA68, a mutant partially deficient in swimming and swarming motility was identified in a new locus that encodes a predicted protein of unknown function annotated PA5017 in the P. aeruginosa PAO1 genome sequence. Chemotaxis plate assay indicated that inactivation of the PA5017 gene led to a decreased chemotactic response. Complementation of the PA5017 mutant with the wild-type PA5017 gene restored normal motility and chemotaxis phenotype. A promoter-lacZ reporter activity assay of the cheYZAB operon from chemotaxis gene cluster 1 showed that there was almost a twofold difference in expression levels of the wild-type PA68 and the PA5017 mutant. This suggested that the PA5017 affected expression of the cheYZAB operon negatively. Further study showed that inactivation of the PA5017 gene in PA68 led to increased biofilm formation in a static system and to the formation of a heterogeneous biofilm in a flow-chamber system. These results suggested that PA5017 possibly affected flagellum-dependent motility and in turn biofilm formation via the chemotaxis signal transduction pathway.

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Available from: Huiming Xia, Sep 02, 2014
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    • "It is known in E. coli and S. Typhimurium that c-di-GMP binds the YcgR protein and this complex interacts with the flagellar motor to reduce velocity and inhibit rotor reversal events (Ryjenkov et al., 2006; Boehm et al., 2010; Paul et al., 2010; Zorraquino et al., 2013). A P. aeruginosa pch mutant reduces swimming and swarming motility as determined by bulk, agar-based assays (Li et al., 2007; Roy et al., 2012). "
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