Prioritization of polysaccharide utilization and control of regulator activation in Bacteroides thetaiotaomicron

Nathan D. Schwalm, Guy E. Townsend, Eduardo A. Groisman

Research output: Contribution to journalArticlepeer-review

14 Scopus citations

Abstract

Bacteroides thetaiotaomicron is a human gut symbiotic bacterium that utilizes a myriad of host dietary and mucosal polysaccharides. The proteins responsible for the uptake and breakdown of many of these polysaccharides are transcriptionally regulated by hybrid two-component systems (HTCSs). These systems consist of a single polypeptide harboring the domains of sensor kinases and response regulators, and thus, are thought to autophosphorylate in response to specific signals. We now report that the HTCS BT0366 is phosphorylated in vivo when B. thetaiotaomicron experiences the BT0366 inducer arabinan but not when grown in the presence of glucose. BT0366 phosphorylation and transcription of BT0366-activated genes requires the conserved predicted sites of phosphorylation in BT0366. When chondroitin sulfate is added to arabinan-containing cultures, BT0366 phosphorylation and transcription of BT0366-activated genes are inhibited and the bacterium exhibits diauxic growth. Whereas 20 additional combinations of polysaccharides also give rise to diauxic growth, other combinations result in synergistic or unaltered growth relative to bacteria experiencing a single polysaccharide. The different strategies employed by B. thetaiotaomicron when faced with multiple polysaccharides may aid its competitiveness in the mammalian gut.

Original languageEnglish (US)
Pages (from-to)32-45
Number of pages14
JournalMolecular Microbiology
Volume104
Issue number1
DOIs
StatePublished - Apr 1 2017

All Science Journal Classification (ASJC) codes

  • Microbiology
  • Molecular Biology

Fingerprint Dive into the research topics of 'Prioritization of polysaccharide utilization and control of regulator activation in Bacteroides thetaiotaomicron'. Together they form a unique fingerprint.

Cite this