title: Yersinia enterocolitica type III secretion depends on the proton motive force but not on the flagellar motor components MotA and MotB.
abstract: The flagellum is believed to be the common ancestor of all type III secretion systems (TTSSs). In Yersinia enterocolitica, expression of the flagellar TTSS and the Ysc (Yop secretion) TTSS are inversely regulated. We therefore hypothesized that the Ysc TTSS may adopt flagellar motor components in order to use the pathogenicity-related translocon in a drill-like manner. As a prerequisite for this hypothesis, we first tested a requirement for the proton motive force by both systems using the protonophore carbonyl cyanide m-chlorophenylhydrazone (CCCP). Motility as well as type III-dependent secretion of Yop proteins was inhibited by CCCP. We deleted motAB, which resulted in an immotile phenotype. This mutant, however, secreted amounts of Yops to the supernatant comparable to those of the wild type. Translocation of Yops into host cells was also not affected by the motAB deletion. Virulence of the mutant was comparable to that of the wild type in the mouse oral infection model. Thus, the hypothesis that the Ysc TTSS might adopt flagellar motor components was not confirmed. The finding that, in addition to consumption of ATP, Ysc TTSS requires the proton motive force is discussed.
authors.affiliation: Bakteriologie, Max von Pettenkofer-Institut, Pettenkoferstrasse 9a, D-80336 Munich, Germany. maier@m3401.mpk.med.uni-muenchen.de
authors.forename: Gottfried
authors.initials: G
authors.lastname: Wilharm
authors.forename: Verena
authors.initials: V
authors.lastname: Lehmann
authors.forename: Kristina
authors.initials: K
authors.lastname: Krauss
authors.forename: Beatrix
authors.initials: B
authors.lastname: Lehnert
authors.forename: Susanna
authors.initials: S
authors.lastname: Richter
authors.forename: Klaus
authors.initials: K
authors.lastname: Ruckdeschel
authors.forename: Jürgen
authors.initials: J
authors.lastname: Heesemann
authors.forename: Konrad
authors.initials: K
authors.lastname: Trülzsch
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism*; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone / Q000494:pharmacology; D005407:Flagella / Q000378:metabolism; D051379:Mice; D018892:Proton-Motive Force / Q000502:physiology*; D014774:Virulence / Q000235:genetics / Q000502:physiology; D015008:Yersinia enterocolitica / Q000187:drug effects / Q000378:metabolism* / Q000472:pathogenicity
chemical_list: D001426:Bacterial Proteins; C063010:MotA protein, Bacteria; C064779:MotB protein, Bacteria; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone