Archives of Microbiology

, Volume 180, Issue 5, pp 374–379 | Cite as

Transcriptome analysis of the Pseudomonas aeruginosa response to iron

  • Marco Palma
  • Stefan Worgall
  • Luis E. N. QuadriEmail author
Short Communication


To successfully infect humans, Pseudomonas aeruginosa (Pa) must overcome the low iron availability in host tissues. A transcriptome comparison was carried out between iron-starved cells of Pa treated with iron and untreated controls. The present study is the first global analysis of the early transcriptional response of exponentially growing Pa to iron. Approximately 1.3% of the Pa genes displayed ≥5.0-fold changes in mRNA levels in iron-treated cells. Treatment affected the mRNA levels of many genes required for iron acquisition as well as several genes with relevance to virulence previously known to be regulated by iron. More importantly, the analysis permitted identification of 107 Pa genes whose mRNA levels were not previously known to be affected by iron. These genes are good candidates for mutagenesis studies aimed at identifying novel functions relevant to iron metabolism in Pa. Some of these genes encode predicted siderophore receptors, iron transport systems, TonB-dependent receptors, regulatory proteins, and proteins relevant to virulence. Notably, 49 genes encode hypothetical or conserved hypothetical proteins of unknown function, suggesting that they are involved directly or indirectly in iron metabolism or metabolic adaptation to different iron-availability conditions.


Pseudomonas Microarray Gene expression Iron Transcriptome Virulence Genomics 



This work was supported by Cystic Fibrosis Foundation grant QUADRI00V0 and the Niarchos Foundation. We also acknowledge the support of the William Randolph Hearst Foundation. We thank Dr. Sung Um for technical assistance.

Supplementary material

supp.pdf (163 kb)
Supplementary material (PDF 163 KB)


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Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Marco Palma
    • 1
  • Stefan Worgall
    • 2
  • Luis E. N. Quadri
    • 1
    Email author
  1. 1.Department of Microbiology and ImmunologyWeill Medical College of Cornell UniversityNew YorkUSA
  2. 2.Department of Genetic MedicineWeill Medical College of Cornell UniversityNew YorkUSA

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