title: The Lon protease regulates swarming motility and virulence gene expression in Proteus mirabilis.
abstract: A mini-Tn5lacZ1 transposon insertion in a gene encoding an orthologue of the Lon protease conferred a hyper-swarming phenotype on Proteus mirabilis. The lon mutation increased the accumulation of mRNA for representative class 1 (flhDC), class 2 (fliA) and class 3 (flaA) genes during swarmer cell differentiation. In addition, the stability of the FlhD protein was fourfold higher in the lon : mini-Tn5lacZ1 background. Expression of a single-copy lon : lacZ fusion increased during the swarming cycle and reached peak levels of expression at a point just after swarmer cell differentiation had initiated. In liquid media, a condition normally non-permissive for swarming, the lon : : mini-Tn5lacZ1 insertion resulted in motile, highly elongated cells that overexpressed flagellin. Finally, the lon : : mini-Tn5lacZ1 mutation was shown to result in increased expression of the hpmBA and zapA virulence genes during swarmer cell differentiation.
authors.affiliation: Research Service, Veterans Affairs Medical Center, Decatur, GA, USA.
authors.forename: Katy M
authors.initials: KM
authors.lastname: Clemmer
authors.affiliation: Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, USA.|Research Service, Veterans Affairs Medical Center, Decatur, GA, USA.
authors.forename: Philip N
authors.initials: PN
authors.lastname: Rather
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D015152:Blotting, Northern; D002465:Cell Movement; D003001:Cloning, Molecular; D017931:DNA Primers; D004251:DNA Transposable Elements; D005407:Flagella / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial; D009154:Mutation; D010641:Phenotype; D016133:Polymerase Chain Reaction; D049070:Protease La / Q000235:genetics / Q000378:metabolism*; D011513:Proteus mirabilis / Q000201:enzymology* / Q000235:genetics* / Q000472:pathogenicity / Q000502:physiology; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D017931:DNA Primers; D004251:DNA Transposable Elements; D049070:Protease La