These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Iron(III) coordination properties of a pyoverdin siderophore produced by Pseudomonas putida ATCC 33015.
    Author: Boukhalfa H, Reilly SD, Michalczyk R, Iyer S, Neu MP.
    Journal: Inorg Chem; 2006 Jul 10; 45(14):5607-16. PubMed ID: 16813425.
    Abstract:
    The iron complexation of a fluorescent green pyoverdin siderophore produced by the environmental bacterium Pseudomonas putida was characterized by solution thermodynamic methods. Pyoverdin binds iron through three bidentate chelate groups, a catecholate, a hydroxamate, and an alpha-hydroxycarboxylic acid. The deprotonation constants of the free pyoverdin and Fe(III)-pyoverdin complex were determined through a series of potentiometric and spectrophotometric experiments. The ferric complex of pyoverdin forms at very low pH (pH < 2), but full iron coordination does not occur until neutral pH. The calculated pM value of 25.13 is slightly lower than that for pyoverdin PaA (pM = 27), which coordinates iron by a catecholate and two hydroxamate groups. The redox potential of Fe-pyoverdin was found to be very pH sensitive. At high pH (approximately pH 9-11) where pyoverdin coordinates Fe in a hexadentate mode the redox potential is -0.480 V (NHE); however, at neutral pH where full Fe coordination is incomplete, the redox potential is more positive (E(1/2) = -0.395 V). The positive shift in the redox potential and the partial dissociation of the Fe-pyoverdin complex with pH decrease provides a path toward in vivo iron release.
    [Abstract] [Full Text] [Related] [New Search]