FeoC from Klebsiella pneumoniae contains a [4Fe-4S] cluster

Kuang Lung Hsueh, Liang Kun Yu, Yung Han Chen, Ya Hsin Cheng, Yin Cheng Hsieh, Shyue chu Ke, Kuo Wei Hung, Chun Jung Chen, Tai Huang Huang

Research output: Contribution to journalArticle

15 Citations (Scopus)


Iron is essential for pathogen survival, virulence, and colonization. Feo is suggested to function as the ferrous iron (Fe2+) transporter. The enterobacterial Feo system is composed of 3 proteins: FeoB is the indispensable component and is a large membrane protein likely to function as a permease; FeoA is a small Src homology 3 (SH3) domain protein that interacts with FeoB; FeoC is a winged-helix protein containing 4 conserved Cys residues in a sequence suitable for harboring a putative iron-sulfur (Fe-S) cluster. The presence of an iron-sulfur cluster on FeoC has never been shown experimentally. We report that under anaerobic conditions, the recombinant Klebsiella pneumoniae FeoC (KpFeoC) exhibited hyperfine-shifted nuclear magnetic resonance (NMR) and a UV-visible (UV-Vis) absorbance spectrum characteristic of a paramagnetic center. The electron paramagnetic resonance (EPR) and extended X-ray absorption fine structure (EXAFS) results were consistent only with the [4Fe-4S] clusters. Substituting the cysteinyl sulfur with oxygen resulted in significantly reduced cluster stability, establishing the roles of these cysteines as the ligands for the Fe-S cluster. When exposed to oxygen, the [4Fe-4S] cluster degraded to [3Fe-4S] and eventually disappeared. We propose that KpFeoC may regulate the function of the Feo transporter through the oxygen- or iron-sensitive coordination of the Fe-S cluster.

Original languageEnglish
Pages (from-to)4726-4734
Number of pages9
JournalJournal of Bacteriology
Issue number20
Publication statusPublished - 2013 Oct 18

ASJC Scopus subject areas

  • Microbiology
  • Molecular Biology

Fingerprint Dive into the research topics of 'FeoC from Klebsiella pneumoniae contains a [4Fe-4S] cluster'. Together they form a unique fingerprint.

  • Cite this

    Hsueh, K. L., Yu, L. K., Chen, Y. H., Cheng, Y. H., Hsieh, Y. C., Ke, S. C., Hung, K. W., Chen, C. J., & Huang, T. H. (2013). FeoC from Klebsiella pneumoniae contains a [4Fe-4S] cluster. Journal of Bacteriology, 195(20), 4726-4734. https://doi.org/10.1128/JB.00687-13