Nature Reviews Microbiology 11, 277-284 (April 2013) | doi:10.1038/nrmicro2989

Opinion'Blooming' in the gut: how dysbiosis might contribute to pathogen evolution

Bärbel Stecher1, Lisa Maier2 & Wolf-Dietrich Hardt2  About the authors


Hundreds of bacterial species make up the mammalian intestinal microbiota. Following perturbations by antibiotics, diet, immune deficiency or infection, this ecosystem can shift to a state of dysbiosis. This can involve overgrowth (blooming) of otherwise under-represented or potentially harmful bacteria (for example, pathobionts). Here, we present evidence suggesting that dysbiosis fuels horizontal gene transfer between members of this ecosystem, facilitating the transfer of virulence and antibiotic resistance genes and thereby promoting pathogen evolution.

Author affiliations

  1. Bärbel Stecher is at the German Centre for Infection Research and the Max von Pettenkofer-Institut, Ludwig-Maximilians-Universität München, Pettenkoferstrasse 9, 80336 Munich, Germany.
  2. Lisa Maier and Wolf-Dietrich Hardt are at the Institute of Microbiology, ETH Zürich, Wolfgang-Pauli-Strasse 10, 8093 Zurich, Switzerland.

Correspondence to: Wolf-Dietrich Hardt2 Email:

Published online 11 March 2013