title: Pleiotropic effects of a Yersinia enterocolitica ompR mutation on adherent-invasive abilities and biofilm formation.
abstract: The OmpR regulator positively influences flagella synthesis and negatively regulates invasin expression in Yersinia enterocolitica. To determine the physiological consequences of this inverse regulation, we analyzed the effect of the ompR mutation on the ability of Y. enterocolitica Ye9 (serotype O9, biotype 2) to adhere to and invade human epithelial HEp-2 cells and to form biofilms. Cell culture assays with ompR, flhDC and inv mutant strains, which vary in their motility and invasin expression, confirmed the important contribution of flagella to the adherent-invasive abilities of Y. enterocolitica Ye9. However, the loss of motility in the ompR strain was apparently not responsible for its low adhesion ability. When the nonmotile phenotype of the ompR mutant was artificially eliminated, an elevated level of invasion, exceeding that of the wild-type strain, was observed. Confocal laser microscopy demonstrated a decrease in the biofilm formation ability of the ompR strain that was only partially correlated with its loss of motility. These data provide evidence that OmpR promotes biofilm formation in this particular strain of Y. enterocolitica, although additional OmpR-dependent factors are also required. In addition, our findings suggest that OmpR-dependent regulation of biofilm formation could be an additional aspect of OmpR regulatory function.
authors.affiliation: Department of Applied Microbiology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Poland.
authors.forename: Adrianna
authors.initials: A
authors.lastname: Raczkowska
authors.forename: Karolina
authors.initials: K
authors.lastname: Skorek
authors.forename: Marta
authors.initials: M
authors.lastname: Brzóstkowska
authors.forename: Anna
authors.initials: A
authors.lastname: Lasińska
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Brzostek
mesh_terms: D001422:Bacterial Adhesion / Q000235:genetics; D001426:Bacterial Proteins / Q000378:metabolism*; D018441:Biofilms; D002460:Cell Line; D005798:Genes, Bacterial / Q000235:genetics; D006801:Humans; D009154:Mutation / Q000235:genetics*; D015534:Trans-Activators / Q000378:metabolism*; D015008:Yersinia enterocolitica / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; D015534:Trans-Activators; C112177:osmolarity response regulator proteins