title: The RNA Chaperone Hfq Is Essential for Virulence and Modulates the Expression of Four Adhesins in Yersinia enterocolitica.
abstract: In Enterobacteriaceae, the RNA chaperone Hfq mediates the interaction of small RNAs with target mRNAs, thereby modulating transcript stability and translation. This post-transcriptional control helps bacteria adapt quickly to changing environmental conditions. Our previous mutational analysis showed that Hfq is involved in metabolism and stress survival in the enteropathogen Yersinia enterocolitica. In this study we demonstrate that Hfq is essential for virulence in mice and influences production of surface pathogenicity factors, in particular lipopolysaccharide and adhesins mediating interaction with host tissue. Hfq inhibited the production of Ail, the Ail-like protein OmpX and the MyfA pilin post-transcriptionally. In contrast Hfq promoted production of two major autotransporter adhesins YadA and InvA. While protein secretion in vitro was not affected, hfq mutants exhibited decreased protein translocation by the type III secretion system into host cells, consistent with decreased production of YadA and InvA. The influence of Hfq on YadA resulted from a complex interplay of transcriptional, post-transcriptional and likely post-translational effects. Hfq regulated invA by modulating the expression of the transcriptional regulators rovA, phoP and ompR. Therefore, Hfq is a global coordinator of surface virulence determinants in Y. enterocolitica suggesting that it constitutes an attractive target for developing new antimicrobial strategies.
authors.affiliation: Max von Pettenkofer Institute for Hygiene and Medical Microbiology, Ludwig Maximilians University, Pettenkoferstrasse 9a, 80336 Munich, Germany.
authors.forename: Tamara Katharina
authors.initials: TK
authors.lastname: Kakoschke
authors.affiliation: Max von Pettenkofer Institute for Hygiene and Medical Microbiology, Ludwig Maximilians University, Pettenkoferstrasse 9a, 80336 Munich, Germany.
authors.forename: Sara Carina
authors.initials: SC
authors.lastname: Kakoschke
authors.affiliation: Max von Pettenkofer Institute for Hygiene and Medical Microbiology, Ludwig Maximilians University, Pettenkoferstrasse 9a, 80336 Munich, Germany.
authors.forename: Catharina
authors.initials: C
authors.lastname: Zeuzem
authors.affiliation: Max von Pettenkofer Institute for Hygiene and Medical Microbiology, Ludwig Maximilians University, Pettenkoferstrasse 9a, 80336 Munich, Germany.
authors.forename: Hicham
authors.initials: H
authors.lastname: Bouabe
authors.affiliation: Max von Pettenkofer Institute for Hygiene and Medical Microbiology, Ludwig Maximilians University, Pettenkoferstrasse 9a, 80336 Munich, Germany.
authors.forename: Kristin
authors.initials: K
authors.lastname: Adler
authors.affiliation: Max von Pettenkofer Institute for Hygiene and Medical Microbiology, Ludwig Maximilians University, Pettenkoferstrasse 9a, 80336 Munich, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Heesemann
authors.affiliation: Max von Pettenkofer Institute for Hygiene and Medical Microbiology, Ludwig Maximilians University, Pettenkoferstrasse 9a, 80336 Munich, Germany.
authors.forename: Ombeline
authors.initials: O
authors.lastname: Rossier
mesh_terms: D018829:Adhesins, Bacterial / Q000378:metabolism*; D000818:Animals; D004195:Disease Models, Animal; D015964:Gene Expression Regulation, Bacterial; D035001:Host Factor 1 Protein / Q000378:metabolism*; D051379:Mice; D014774:Virulence; D037521:Virulence Factors / Q000378:metabolism*; D015009:Yersinia Infections / Q000382:microbiology / Q000473:pathology; D015008:Yersinia enterocolitica / Q000378:metabolism / Q000472:pathogenicity*
chemical_list: D018829:Adhesins, Bacterial; D035001:Host Factor 1 Protein; D037521:Virulence Factors