Evolutionary resurrection of flagellar motility via rewiring of the nitrogen regulation system

Research output: Contribution to journalArticle

Authors

  • Tiffany B. Taylor
  • Geraldine Mulley
  • Alexander H. Dills
  • Abdullah S. Alsohim
  • Liam J. McGuffin
  • David J. Studholme
  • Mark W. Silby
  • Michael A. Brockhurst
  • Louise J. Johnson

Colleges, School and Institutes

External organisations

  • University of Reading
  • University of Massachusetts Dartmouth
  • Qassim University
  • University of Exeter
  • University of York
  • School of Biological Sciences
  • The University of Akureyri

Abstract

A central process in evolution is the recruitment of genes to regulatory networks. We engineered immotile strains of the bacterium Pseudomonas fluorescens that lack flagella due to deletion of the regulatory gene fleQ. Under strong selection for motility, these bacteria consistently regained flagella within 96 hours via a two-step evolutionary pathway. Step 1 mutations increase intracellular levels of phosphorylated NtrC, a distant homolog of FleQ, which begins to commandeer control of the fleQ regulon at the cost of disrupting nitrogen uptake and assimilation. Step 2 is a switch-of-function mutation that redirects NtrC away from nitrogen uptake and toward its novel function as a flagellar regulator. Our results demonstrate that natural selection can rapidly rewire regulatory networks in very few, repeatable mutational steps.

Details

Original languageEnglish
Pages (from-to)1014-1017
Number of pages4
JournalScience
Volume347
Issue number6225
Publication statusPublished - 27 Feb 2015

ASJC Scopus subject areas