Disruption of Heme Uptake and PrrF sRNA Expression in the Pseudomonas aeruginosa PhuS H209A Variant Induces a Metabolic Stress-Response

ABSTRACT: The Pseudomonas aeruginosa heme-binding protein PhuS plays a central role in coordinating heme utilization with iron homeostasis through the PrrF small RNAs. Proteomic and metabolomic analyses of the phuSH209A allelic strain demonstrated that the previously characterized in vitro disruption of PhuS function results in widespread regulatory and metabolic perturbations, through its influence on the differential expression of the PrrF small RNAs. Although intracellular iron levels remain unchanged relative to PAO1, the phuSH209A allelic strain exhibits decreased expression of pyochelin (PCH) biosynthetic proteins and increased abundance of iron uptake receptors. This perceived iron dysregulation is consistent with disruption of the PrrF-dependent iron-sparing response, suggesting that PhuS functions beyond heme trafficking as a modulator of iron-dependent post-transcriptional regulation. Specifically, the differential expression of PrrF1 and PrrF2 under heme conditions indicates that PhuS impacts the balance and activity of these sRNAs, which govern iron-responsive metabolic pathways. This includes decreased conservation of anthranilate for quorum sensing (QS) signaling molecules, contributing to reduced Pseudomonas quinolone signal (PQS) production and downstream effects on phenazine and siderophore biosynthesis.

INSTRUMENT(S):

ORGANISM(S): Pseudomonas Aeruginosa Pa103

SUBMITTER: Mehari Weldemariam  

LAB HEAD: Maureen A Kane

PROVIDER: PXD079786 | Pride | 2026-09-28

REPOSITORIES: Pride