Phage-Mediated Iron Acquisition by Pseudomonas aeruginosa

Area of Science:

• Microbiology
• Bacteriology
• Virology

Background:

• Iron acquisition is essential for bacterial survival and disease development.
• The human pathogen *Pseudomonas aeruginosa* relies on efficient iron uptake mechanisms.
• Bacteriophages (phages) are viruses that infect bacteria and can influence bacterial populations.

Purpose of the Study:

• To investigate a novel mechanism of iron acquisition in *Pseudomonas aeruginosa*.
• To explore the role of bacteriophages in bacterial iron uptake and pathogenesis.
• To understand the interaction between *P. aeruginosa*, phages, and iron availability.

Main Methods:

• Induction of Pf phage under iron-deplete conditions.
• Assessment of Pf virion binding to free iron.
• Quantification of bacterial growth with and without Pf-bound iron.
• Analysis of type IV pili involvement in phage attachment and iron uptake.

Main Results:

• Pf phage is highly induced in iron-depleted environments.
• Pf virions bind and concentrate free iron, enhancing its utilization by *P. aeruginosa*.
• Type IV pili mediate Pf attachment, enabling strain-selective uptake of phage-bound iron and conferring a fitness advantage.

Conclusions:

• Filamentous phages play an unrecognized role in bacterial iron acquisition.
• A novel phage-bacterium partnership facilitates iron uptake in *P. aeruginosa*.
• This interaction involves selective kin cooperation and provides a competitive edge in polymicrobial environments.