Glycan foraging in vivo by an intestine-adapted bacterial symbiont

Science. 2005 Mar 25;307(5717):1955-9. doi: 10.1126/science.1109051.

Abstract

Germ-free mice were maintained on polysaccharide-rich or simple-sugar diets and colonized for 10 days with an organism also found in human guts, Bacteroides thetaiotaomicron, followed by whole-genome transcriptional profiling of bacteria and mass spectrometry of cecal glycans. We found that these bacteria assembled on food particles and mucus, selectively induced outer-membrane polysaccharide-binding proteins and glycoside hydrolases, prioritized the consumption of liberated hexose sugars, and revealed a capacity to turn to host mucus glycans when polysaccharides were absent from the diet. This flexible foraging behavior should contribute to ecosystem stability and functional diversity.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adaptation, Physiological
  • Animals
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Bacteroides / enzymology
  • Bacteroides / genetics
  • Bacteroides / growth & development
  • Bacteroides / metabolism*
  • Cecum / microbiology*
  • Cluster Analysis
  • Diet
  • Dietary Carbohydrates / metabolism
  • Ecosystem
  • Gene Expression Profiling
  • Gene Expression Regulation, Bacterial
  • Germ-Free Life
  • Glycoside Hydrolases / genetics
  • Glycoside Hydrolases / metabolism
  • Hexoses / metabolism
  • Intestines / microbiology
  • Male
  • Mice
  • Mucus / metabolism
  • Oligonucleotide Array Sequence Analysis
  • Operon
  • Polysaccharide-Lyases / genetics
  • Polysaccharide-Lyases / metabolism
  • Polysaccharides / metabolism*
  • Symbiosis*
  • Transcription, Genetic
  • Up-Regulation

Substances

  • Bacterial Proteins
  • Dietary Carbohydrates
  • Hexoses
  • Polysaccharides
  • Glycoside Hydrolases
  • Polysaccharide-Lyases