Copper import in Escherichia coli by the yersiniabactin metallophore system

Nat Chem Biol. 2017 Sep;13(9):1016-1021. doi: 10.1038/nchembio.2441. Epub 2017 Jul 24.

Abstract

Copper plays a dual role as a nutrient and a toxin during bacterial infections. While uropathogenic Escherichia coli (UPEC) strains can use the copper-binding metallophore yersiniabactin (Ybt) to resist copper toxicity, Ybt also converts bioavailable copper to Cu(II)-Ybt in low-copper conditions. Although E. coli have long been considered to lack a copper import pathway, we observed Ybt-mediated copper import in UPEC using canonical Fe(III)-Ybt transport proteins. UPEC removed copper from Cu(II)-Ybt with subsequent re-export of metal-free Ybt to the extracellular space. Copper released through this process became available to an E. coli cuproenzyme (the amine oxidase TynA), linking this import pathway to a nutrient acquisition function. Ybt-expressing E. coli thus engage in nutritional passivation, a strategy of minimizing a metal ion's toxicity while preserving its nutritional availability. Copper acquisition through this process may contribute to the marked virulence defect of Ybt-transport-deficient UPEC.

MeSH terms

  • Copper / classification*
  • Copper / metabolism
  • Copper / toxicity
  • Escherichia coli* / drug effects
  • Escherichia coli* / metabolism
  • Phenols / metabolism*
  • Thiazoles / metabolism*

Substances

  • Phenols
  • Thiazoles
  • yersiniabactin
  • Copper