, Volume 22, Issue 4, pp 691–695 | Cite as

Salmochelin, the long-overlooked catecholate siderophore of Salmonella

  • Silke I. Müller
  • Marianne Valdebenito
  • Klaus HantkeEmail author


Salmochelin is a C-glucosylated enterobactin produced by Salmonella species, uropathogenic and avian pathogenic Escherichia coli strains, and certain Klebsiella strains. It was the first glucosylated siderophore described. The glucosylation has been interpreted as a bacterial evasion mechanism against the mammalian catecholate siderophore-binding protein siderocalin (NGAL-lipocalin). The synthesis, excretion, and uptake of salmochelin requires five genes, iroBCDEN, and also the enterobactin biosynthesis and utilization system. Some salmochelin-producing strains also secrete microcins, which possess a C-terminal, linear glucosyl-enterobactin moiety. These microcins recognize the catecholate siderophore receptors IroN, Cir, Fiu, and FepA, and may inhibit the growth of competitors for catecholate siderophores.


Salmochelin Iron transport Siderocalin Salmonella C-glucosylation Microcin E492 



We thank Andreas Kulik for help with the illustrations, G. Winkelmann and the group of R. D. Süßmuth group for collaborations, and V. Braun and Karen Brune (Marburg) for comments on the manuscript and editing. Financial support by the DFG is gratefully acknowledged.


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Copyright information

© Springer Science+Business Media, LLC. 2009

Authors and Affiliations

  • Silke I. Müller
    • 1
  • Marianne Valdebenito
    • 1
  • Klaus Hantke
    • 1
    Email author
  1. 1.Lehrstuhl für Mikrobiologie – Organismische InteraktionenUniversität TübingenTübingenGermany

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