Linking E. coli to fibrosis in Crohn's disease.

Intestinal fibrosis associated with Crohn's disease is a serious yet poorly understood clinical complication. In this issue of Cell Host & Microbe, Ahn and colleagues provide evidence that the adherent intestinal E. coli produced the metallophore yersiniabactin, which sequesters zinc to drive intestinal fibrosis in a HIF-1α-dependent manner.