title: Absence of YbeY RNase compromises the growth and enhances the virulence plasmid gene expression of Yersinia enterocolitica O:3.
abstract: YbeY was recently recognized as an endoribonuclease playing a role in ribosome biosynthesis. In Escherichia coli it functions as a single-strand-specific RNase that processes the 3' end of the 16S rRNA and is crucial for the late-stage 70S ribosome quality control system. Here we report that YbeY is not essential in Yersinia enterocolitica serotype O:3, yet its absence strongly compromised the bacterium. The lack of YbeY resulted in misprocessing of 16S rRNA and a severe decrease of growth rate with complete growth arrest observed at elevated temperatures. Moreover, a ybeY mutation severely disturbed regulation of the Yersinia virulence plasmid (pYV) genes and affected the expression of regulatory small RNA species. Transcription of the pYV genes was upregulated in the ybeY mutant at 22 °C; the same genes were repressed in the wild-type bacterium. Furthermore, ybeY inactivation impaired many virulence-related features, such as resistance to elevated temperature and acid, and hindered utilization of different carbohydrates. In addition, the ybeY mutant strain showed decreased infectivity in a tissue culture infection model, especially at the stage of cell adhesion. Taken together, this study demonstrates the crucial role of YbeY in Y. enterocolitica O:3 physiology and pathogenicity.
authors.affiliation: Haartman Institute, Department of Bacteriology and Immunology, Research Programs Unit, Immunobiology, University of Helsinki, Finland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Leskinen
authors.affiliation: Biocentrum Helsinki, Finland: Finnish Institute of Molecular Medicine, Finland.|Institute of Biotechnology, University of Helsinki, Finland.
authors.forename: Markku
authors.initials: M
authors.lastname: Varjosalo
authors.affiliation: Helsinki University Central Hospital Laboratory Diagnostics, Helsinki, Finland.|Haartman Institute, Department of Bacteriology and Immunology, Research Programs Unit, Immunobiology, University of Helsinki, Finland.
authors.forename: Mikael
authors.initials: M
authors.lastname: Skurnik
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D010957:Plasmids / Q000235:genetics* / Q000378:metabolism; D012260:Ribonucleases / Q000191:economics* / Q000235:genetics; D014774:Virulence; D015009:Yersinia Infections / Q000382:microbiology; D015008:Yersinia enterocolitica / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development* / Q000472:pathogenicity
chemical_list: D001426:Bacterial Proteins; D012260:Ribonucleases