RT Journal Article
SR Electronic
T1 Heme dependent transcriptional regulation of the <em>Pseudomonas aeruginosa</em> tandem sRNA <em>prrF1,F2</em> locus by the cytoplasmic heme binding protein PhuS
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.11.18.388926
DO 10.1101/2020.11.18.388926
A1 Tyree Wilson
A1 Susana Mouriño
A1 Angela Wilks
YR 2020
UL http://biorxiv.org/content/early/2020/11/19/2020.11.18.388926.abstract
AB Pseudomonas aeruginosa is an opportunistic pathogen requiring iron for its survival and virulence. P. aeruginosa can acquire iron from heme via the heme assimilation system (Has) and Pseudomonas heme uptake (Phu) systems. The Has and Phu systems have non-redundant roles in heme sensing and transport, respectively. However, despite their respective roles heme taken up by either the Has or Phu system is regulated at the metabolic level by the cytoplasmic heme binding protein PhuS, which controls heme flux through the iron-regulated heme oxygenase HemO. Herein, through a combination of CHIP-PCR, EMSA and fluorescence anisotropy we show PhuS binds upstream of the tandem iron-responsive sRNAs prrF1,F2. Furthermore, qPCR analysis of the PAO1 WT and ΔphuS allelic strain shows loss of PhuS abrogates the heme dependent regulation of PrrH. Taken together our data shows PhuS, in addition to its role in regulating extracellular heme metabolism also functions as a transcriptional regulator of the heme-dependent sRNA, PrrH. This dual function of PhuS is central to integrating extracellular heme utilization into the PrrF/PrrH sRNA regulatory network critical for P. aeruginosa adaptation and virulence within the host.PAO1Pseudomonas aeruginosa O1PrrFPseudomonasRNAresponsive to ironPrrHPseudomonasRNAresponsive to hemeHasHeme assimilation systemPhuPseudomonas heme uptakeBVIXbiliverdinECFextra cytoplasmic functionABC-transport systemATP-dependent binding cassette transport systemFAFluorescence anisotropy