The Influence of Iron on Pseudomonas aeruginosa Physiology: A regulatory link between iron and quorum sensing

ECU Author/Contributor (non-ECU co-authors, if there are any, appear on document)

John M. III Farrow (Creator)

E. P. Greenberg (Creator)

Joon-Hee Lee (Creator)

Amanda G. Oglesby (Creator)

Everett C. Pesci (Creator)

Andrew P. Tomaras (Creator)

Michael L. Vasil (Creator)

Institution

East Carolina University (ECU )

Web Site: http://www.ecu.edu/lib/

Abstract: In iron-replete environments the Pseudomonas aeruginosa Fur (ferric uptake regulator) protein represses expression of two small regulatory RNAs encoded by prrF1 and prrF2. Here we describe the effects of iron and PrrF regulation on P. aeruginosa physiology. We show that PrrF represses genes encoding enzymes for the degradation of anthranilate (i.e. antABC) a precursor of the Pseudomonas quinolone signal (PQS). Under ironlimiting conditions PQS production was greatly decreased in a ∆ prrF1 2 mutant as compared with wild type. The addition of anthranilate to the growth medium restored PQS production to the ∆ prrF1 2 mutant indicating that its defect in PQS production is a consequence of anthranilate degradation. PA2511 was shown to encode an anthranilate-dependent activator of the ant genes and was subsequently renamed antR. AntR was not required for regulation of antA by PrrF but was required for optimal iron activation of antA. Furthermore iron was capable of activating both antA and antR in a ∆ prrF1 2 mutant indicating the presence of two distinct yet overlapping pathways for iron activation of antA (AntR-dependent and PrrF-dependent). Additionally several quorum-sensing regulators including PqsR influenced antA expression demonstrating that regulation of anthranilate metabolism is intimately woven into the quorum-sensing network of P. aeruginosa. Overall our data illustrate the extensive control that both iron regulation and quorum sensing exercise in basic cellular physiology underlining how intermediary metabolism can affect the regulation of virulence factors in P. aeruginosa. Originally published Journal of Biological Chemistry vol. 283 No. 23 June 2008

Additional Information

Publication

Other

The Journal of Biological Chemistry. 283:23(June 2008) p. 15558-15567.

Language: English

Date: 2011

Keywords

Pseudomonas aeruginosa, anthranilate, quorum sensing, iron environment

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