HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 282, Issue 5, 2987-2995, February 2, 2007

This Article Full Text Full Text (PDF) All Versions of this Article: 282/5/2987    most recent M609238200v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Greenwald, J. Articles by Schalk, I. J. Search for Related Content PubMed PubMed Citation Articles by Greenwald, J. Articles by Schalk, I. J. Social Bookmarking                      What's this?

Real Time Fluorescent Resonance Energy Transfer Visualization of Ferric Pyoverdine Uptake in Pseudomonas aeruginosa

A ROLE FOR FERROUS IRON^*

Jason Greenwald¹², Françoise Hoegy¹, Mirella Nader, Laure Journet², Gaëtan L. A. Mislin, Peter L. Graumann, and Isabelle J. Schalk³

From the Métaux et Microorganismes: Chimie, Biologie, et Applications, UMR 7175-LC1 Institut Gilbert-Laustriat, CNRS-Université Louis Pasteur, ESBS, Boulevard Sébastien Brant, F-67413 Illkirch, Strasbourg, France and the Institüt für Mikrobiologie, Stefan Meier Strasse 19, Albert-Ludwigs-Universität Freiburg, 79104 Freiburg, Germany

To acquire iron, Pseudomonas aeruginosa secretes a major fluorescent siderophore, pyoverdine (PvdI), that chelates iron and shuttles it into the cells via the specific outer membrane transporter, FpvAI. We took advantage of the fluorescence properties of PvdI and its metal chelates as well as the efficient FRET between donor tryptophans in FpvAI and PvdI to follow the fate of the siderophore during iron uptake. Our findings with PvdI-Ga and PvdI-Cr uptake indicate that iron reduction is required for the dissociation of PvdI-Fe, that a ligand exchange for iron occurs, and that this dissociation occurs in the periplasm. We also observed a delay between PvdI-Fe dissociation and the rebinding of PvdI to FpvAI, underlining the kinetic independence of metal release and siderophore recycling. Meanwhile, PvdI is not modified but recycled to the medium, still competent for iron chelation and transport. Finally, in vivo fluorescence microscopy revealed patches of PvdI, suggesting that uptake occurs via macromolecular assemblies on the cell surface.

Received for publication, September 29, 2006 , and in revised form, December 1, 2006.

^* This work was supported in part by the Centre National de la Recherche Scientific, the Association Vaincre la Mucoviscidose (French Association against Cystic Fibrosis), Agence Nationale de Recherche Grant ANR-05-JCJC-0181-01 (to I. S.), and the Deutsche Forschungegemeinschaft (to P. G.). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

¹ These authors contributed equally to this work.

² Supported by European Molecular Biology Organization postdoctoral fellowships.

³ To whom correspondence should be addressed: Métaux et Microorganismes: Chimie, Biologie, et Applications, UMR 7175-LC1 Institut Gilbert-Laustriat, ESBS, Blvd. Sébastien Brant, BP 10412, F-67413 Illkirch, Strasbourg, France. Tel.: 33-3-90-24-47-19; Fax: 33-3-90-24-48-29; E-mail: schalk{at}esbs.u-strasbg.fr.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				J. Greenwald, G. Zeder-Lutz, A. Hagege, H. Celia, and F. Pattus The Metal Dependence of Pyoverdine Interactions with Its Outer Membrane Receptor FpvA J. Bacteriol., October 15, 2008; 190(20): 6548 - 6558. [Abstract] [Full Text] [PDF]

				P. Cornelis Unexpected Interaction of a Siderophore with Aluminum and Its Receptor J. Bacteriol., October 15, 2008; 190(20): 6541 - 6543. [Full Text] [PDF]

				A. M. Jones, S. E. Lindow, and M. C. Wildermuth Salicylic Acid, Yersiniabactin, and Pyoverdin Production by the Model Phytopathogen Pseudomonas syringae pv. tomato DC3000: Synthesis, Regulation, and Impact on Tomato and Arabidopsis Host Plants J. Bacteriol., October 1, 2007; 189(19): 6773 - 6786. [Abstract] [Full Text] [PDF]