Host Imprints on Bacterial Genomes--Rapid, Divergent Evolution in Individual Patients

PLoS Pathog. 2010 Aug 26;6(8):e1001078. doi: 10.1371/journal.ppat.1001078.

Abstract

Bacteria lose or gain genetic material and through selection, new variants become fixed in the population. Here we provide the first, genome-wide example of a single bacterial strain's evolution in different deliberately colonized patients and the surprising insight that hosts appear to personalize their microflora. By first obtaining the complete genome sequence of the prototype asymptomatic bacteriuria strain E. coli 83972 and then resequencing its descendants after therapeutic bladder colonization of different patients, we identified 34 mutations, which affected metabolic and virulence-related genes. Further transcriptome and proteome analysis proved that these genome changes altered bacterial gene expression resulting in unique adaptation patterns in each patient. Our results provide evidence that, in addition to stochastic events, adaptive bacterial evolution is driven by individual host environments. Ongoing loss of gene function supports the hypothesis that evolution towards commensalism rather than virulence is favored during asymptomatic bladder colonization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological / genetics*
  • Electrophoresis, Gel, Pulsed-Field
  • Electrophoretic Mobility Shift Assay
  • Escherichia coli / genetics*
  • Escherichia coli / immunology
  • Escherichia coli / pathogenicity
  • Escherichia coli Infections / genetics*
  • Escherichia coli Infections / immunology
  • Evolution, Molecular*
  • Gene Expression
  • Gene Expression Profiling
  • Genome, Bacterial / genetics*
  • Host-Pathogen Interactions / genetics*
  • Host-Pathogen Interactions / immunology
  • Humans
  • Oligonucleotide Array Sequence Analysis
  • Reverse Transcriptase Polymerase Chain Reaction
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Urinary Bladder / microbiology
  • Urinary Tract Infections / immunology
  • Urinary Tract Infections / microbiology
  • Virulence / genetics