title: The prrF-encoded small regulatory RNAs are required for iron homeostasis and virulence of Pseudomonas aeruginosa.
abstract: Pseudomonas aeruginosa is an opportunistic pathogen that requires iron to cause infection, but it also must regulate the uptake of iron to avoid iron toxicity. The iron-responsive PrrF1 and PrrF2 small regulatory RNAs (sRNAs) are part of P. aeruginosa's iron regulatory network and affect the expression of at least 50 genes encoding iron-containing proteins. The genes encoding the PrrF1 and PrrF2 sRNAs are encoded in tandem in P. aeruginosa, allowing for the expression of a distinct, heme-responsive sRNA named PrrH that appears to regulate genes involved in heme metabolism. Using a combination of growth, mass spectrometry, and gene expression analysis, we showed that the ΔprrF1,2 mutant, which lacks expression of the PrrF and PrrH sRNAs, is defective for both iron and heme homeostasis. We also identified phuS, encoding a heme binding protein involved in heme acquisition, and vreR, encoding a previously identified regulator of P. aeruginosa virulence genes, as novel targets of prrF-mediated heme regulation. Finally, we showed that the prrF locus encoding the PrrF and PrrH sRNAs is required for P. aeruginosa virulence in a murine model of acute lung infection. Moreover, we showed that inoculation with a ΔprrF1,2 deletion mutant protects against future challenge with wild-type P. aeruginosa. Combined, these data demonstrate that the prrF-encoded sRNAs are critical regulators of P. aeruginosa virulence.
authors.affiliation: University of Maryland, Baltimore, School of Medicine, Department of Microbiology and Immunology, Baltimore, Maryland, USA.
authors.forename: Alexandria A
authors.initials: AA
authors.lastname: Reinhart
authors.affiliation: University of Maryland, Baltimore, School of Dentistry, Department of Microbial Pathogenesis, Baltimore, Maryland, USA.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Powell
authors.affiliation: University of Maryland, Baltimore, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, USA.
authors.forename: Angela T
authors.initials: AT
authors.lastname: Nguyen
authors.affiliation: University of Maryland, Baltimore, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, USA.
authors.forename: Maura
authors.initials: M
authors.lastname: O'Neill
authors.affiliation: University of Maryland, Baltimore, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, USA.
authors.forename: Louise
authors.initials: L
authors.lastname: Djapgne
authors.affiliation: University of Maryland, Baltimore, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, USA.
authors.forename: Angela
authors.initials: A
authors.lastname: Wilks
authors.affiliation: University of Maryland, Baltimore, School of Medicine, Department of Microbiology and Immunology, Baltimore, Maryland, USA University of Maryland, Baltimore, School of Dentistry, Department of Microbial Pathogenesis, Baltimore, Maryland, USA.
authors.forename: Robert K
authors.initials: RK
authors.lastname: Ernst
authors.affiliation: University of Maryland, Baltimore, School of Medicine, Department of Microbiology and Immunology, Baltimore, Maryland, USA University of Maryland, Baltimore, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, USA aoglesby@rx.umaryland.edu.
authors.forename: Amanda G
authors.initials: AG
authors.lastname: Oglesby-Sherrouse
mesh_terms: D000208:Acute Disease; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D006418:Heme / Q000378:metabolism; D000081062:Heme-Binding Proteins; D006420:Hemeproteins / Q000235:genetics / Q000378:metabolism; D006706:Homeostasis; D006801:Humans; D007114:Immunization; D007501:Iron / Q000378:metabolism*; D008168:Lung / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008969:Molecular Sequence Data; D011552:Pseudomonas Infections / Q000276:immunology / Q000382:microbiology / Q000473:pathology / Q000517:prevention & control*; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000276:immunology / Q000378:metabolism / Q000472:pathogenicity; D022661:RNA, Untranslated / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D017384:Sequence Deletion; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D000081062:Heme-Binding Proteins; D006420:Hemeproteins; D022661:RNA, Untranslated; D006418:Heme; D007501:Iron