A novel streptococcal integrative conjugative element involved in iron acquisition
Heather, Zoe, Holden, Matthew T. G., Steward, Karen F., Parkhill, Julian, Song, Lijiang, Challis, Gregory L., Robinson, Carl, Davis-Poynter, Nicholas and Waller, Andrew S.. (2008) A novel streptococcal integrative conjugative element involved in iron acquisition. Molecular Microbiology, Vol.70 (No.5). pp. 1274-1292. ISSN 0950-382XFull text not available from this repository.
Official URL: http://dx.doi.org/10.1111/j.1365-2958.2008.06481.x
In this study, we determined the function of a novel non-ribosomal peptide synthetase (NRPS) system carried by a streptococcal integrative conjugative element (ICE), ICESe2. The NRPS shares similarity with the yersiniabactin system found in the high-pathogenicity island of Yersinia sp. and is the first of its kind to be identified in streptococci. We named the NRPS product 'equibactin' and genes of this locus eqbA-N. ICESe2, although absolutely conserved in Streptococcus equi, the causative agent of equine strangles, was absent from all strains of the closely related opportunistic pathogen Streptococcus zooepidemicus. Binding of EqbA, a DtxR-like regulator, to the eqbB promoter was increased in the presence of cations. Deletion of eqbA resulted in a small-colony phenotype. Further deletion of the irp2 homologue eqbE, or the genes eqbH, eqbI and eqbJ encoding a putative ABC transporter, or addition of the iron chelator nitrilotriacetate, reversed this phenotype, implicating iron toxicity. Quantification of Fe-55 accumulation and sensitivity to streptonigrin suggested that equibactin is secreted by S. equi and that the eqbH, eqbI and eqbJ genes are required for its associated iron import. In agreement with a structure-based model of equibactin synthesis, supplementation of chemically defined media with salicylate was required for equibactin production.
|Item Type:||Journal Article|
|Subjects:||Q Science > QD Chemistry
Q Science > QR Microbiology
|Divisions:||Faculty of Science > Chemistry|
|Library of Congress Subject Headings (LCSH):||Streptococcus, Genetic transformation, Iron -- Physiological transport, Siderophores|
|Journal or Publication Title:||Molecular Microbiology|
|Publisher:||Wiley-Blackwell Publishing Ltd.|
|Number of Pages:||19|
|Page Range:||pp. 1274-1292|
|Access rights to Published version:||Restricted or Subscription Access|
|Funder:||Horse Trust, Great Britain. Horserace Betting Levy Board (HBLB), Animal Health Trust|
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