University Of Tasmania

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Pseudomonas aeruginosa uses multiple pathways to acquire iron during chronic infection in cystic fibrosis lungs

journal contribution
posted on 2023-05-17, 18:20 authored by Konings, AF, Martin, LW, Sharples, MJ, Louise RoddamLouise Roddam, Roger Latham, Reid, DW, Lamont, IL
Pseudomonas aeruginosa chronically infects the lungs of more than 80% of adult patients with cystic fibrosis (CF) and is a major contributor to progression of disease pathology. P. aeruginosa requires iron for growth and has multiple iron uptake systems that have been studied in bacteria grown in laboratory culture. The purpose of this research was to determine which of these are active during infection in CF. RNA was extracted from 149 sputum samples obtained from 23 CF patients. Reverse transcription-quantitative real time PCR (RT-qPCR) was used to measure expression of P. aeruginosa genes encoding transport systems for the siderophores pyoverdine and pyochelin, for heme, and for ferrous ions. Expression of P. aeruginosa genes could be quantified in 89% of the sputum samples. Expression of genes associated with siderophore-mediated iron uptake was detected in most samples but was at low levels in some samples, indicating that other iron uptake mechanisms are active. Expression of genes encoding heme transport systems was also detected in most samples indicating that heme uptake occurs during infection in CF. Expression of feoB was detected in all sputum samples, implying an important role for ferrous ion uptake by P. aeruginosa in CF. Our data show that multiple P. aeruginosa iron uptake mechanisms are active in chronic CF infection and that RT-qPCR of RNA extracted from sputum provides a powerful tool for investigating bacterial physiology during infection in CF.


National Health & Medical Research Council


Publication title

Infection and Immunity










Tasmanian School of Medicine


Amer Soc Microbiology

Place of publication

1752 N St Nw, Washington, USA, Dc, 20036-2904

Rights statement

Copyright 2013 American Society for Microbiology

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  • Restricted

Socio-economic Objectives

Clinical health not elsewhere classified

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