Abstract
Many bacteria, including numerous human pathogens, synthesize small molecules known as siderophores to scavenge iron. Enterobactin, a siderophore produced by enteric bacteria, is surprisingly ineffective as an iron-scavenging agent for bacteria growing in animals because of its hydrophobicity and its sequestration by the mammalian protein siderocalin, a component of the innate immune system. However, pathogenic strains of Escherichia coli and Salmonella use enzymes encoded by the iroA gene cluster to tailor enterobactin by glycosylation and linearization. The resulting modified forms of enterobactin, known as salmochelins, can evade siderocalin and are less hydrophobic than enterobactin, restoring this siderophore's iron-scavenging ability in mammals.
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Acknowledgements
Research in the authors' laboratories is supported by National Institutes of Health grants AI042738 (to C.T.W.) and GM065400 (to D.R.L.), and by the Howard Hughes Medical Institute (D.R.L.). M.A.F. is supported by a predoctoral fellowship from the Hertz Foundation, and H.L. is supported by a postdoctoral fellowship from the Jane Coffin Childs Memorial Fund. We are grateful to K. Hantke (Universität Tübingen) for helpful discussions.
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Fischbach, M., Lin, H., Liu, D. et al. How pathogenic bacteria evade mammalian sabotage in the battle for iron. Nat Chem Biol 2, 132–138 (2006). https://doi.org/10.1038/nchembio771
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DOI: https://doi.org/10.1038/nchembio771
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