title: The Pseudomonas aeruginosa PrrF Small RNAs Regulate Iron Homeostasis during Acute Murine Lung Infection.
abstract: Pseudomonas aeruginosais a Gram-negative opportunistic pathogen that requires iron for virulence. Iron homeostasis is maintained in part by the PrrF1 and PrrF2 small RNAs (sRNAs), which block the expression of iron-containing proteins under iron-depleted conditions. The PrrF sRNAs also promote the production of thePseudomonasquinolone signal (PQS), a quorum sensing molecule that activates the expression of several virulence genes. The tandem arrangement of theprrFgenes allows for expression of a third sRNA, PrrH, which is predicted to regulate gene expression through its unique sequence derived from theprrF1-prrF2intergenic (IG) sequence (the PrrHIGsequence). Previous studies showed that theprrFlocus is required for acute lung infection. However, the individual functions of the PrrF and PrrH sRNAs were not determined. Here, we describe a system for differentiating PrrF and PrrH functions by deleting the PrrHIGsequence [prrF(ΔHIG)]. Our analyses of this construct indicate that the PrrF sRNAs, but not PrrH, are required for acute lung infection byP. aeruginosaMoreover, we show that the virulence defect of the ΔprrF1-prrF2mutant is due to decreased bacterial burden during acute lung infection.In vivoanalysis of gene expression in lung homogenates shows that PrrF-mediated regulation of genes for iron-containing proteins is disrupted in the ΔprrF1-prrF2mutant during infection, while the expression of genes that mediate PrrF-regulated PQS production are not affected byprrFdeletionin vivoCombined, these studies demonstrate that regulation of iron utilization plays a critical role inP. aeruginosa's ability to survive during infection.
authors.affiliation: University of Maryland, 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, 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, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, USA.
authors.forename: Luke K
authors.initials: LK
authors.lastname: Brewer
authors.affiliation: West Virginia University School of Medicine, Department of Microbiology, Immunology and Cell Biology, Morgantown, West Virginia, USA.
authors.forename: Justin
authors.initials: J
authors.lastname: Bevere
authors.affiliation: University of Maryland, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, USA.
authors.forename: Jace W
authors.initials: JW
authors.lastname: Jones
authors.affiliation: University of Maryland, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, USA.
authors.forename: Maureen A
authors.initials: MA
authors.lastname: Kane
authors.affiliation: West Virginia University School of Medicine, Department of Microbiology, Immunology and Cell Biology, Morgantown, West Virginia, USA.
authors.forename: F Heath
authors.identifier: http://orcid.org/0000-0002-3140-402X
authors.initials: FH
authors.lastname: Damron
authors.affiliation: West Virginia University School of Medicine, Department of Microbiology, Immunology and Cell Biology, Morgantown, West Virginia, USA.
authors.forename: Mariette
authors.initials: M
authors.lastname: Barbier
authors.affiliation: University of Maryland, School of Medicine, Department of Microbiology and Immunology, Baltimore, Maryland, USA aoglesby@rx.umaryland.edu.|University of Maryland, School of Pharmacy, Department of Pharmaceutical Sciences, Baltimore, Maryland, USA.
authors.forename: Amanda G
authors.initials: AG
authors.lastname: Oglesby-Sherrouse
mesh_terms: D000818:Animals; D004252:DNA Mutational Analysis; D004195:Disease Models, Animal; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D006706:Homeostasis; D007501:Iron / Q000378:metabolism*; D008168:Lung / Q000382:microbiology; D051379:Mice; D050296:Microbial Viability; D018410:Pneumonia, Bacterial / Q000382:microbiology*; D011552:Pseudomonas Infections / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism*; D017384:Sequence Deletion; D014774:Virulence
chemical_list: D034741:RNA, Small Interfering; D007501:Iron
keywords: PQS; PrrF; PrrH; Pseudomonas aeruginosa; iron regulation; sRNA; small RNA