Newcastle University

Cell, Volume 141, Issue 7, 1241-1252, 25 June 2010  |  Copyright 2010 Elsevier Inc. All rights reserved.  |  10.1016/j.cell.2010.05.005

Specificity of Polysaccharide Use in Intestinal Bacteroides Species Determines Diet-Induced Microbiota Alterations

Erica D.Sonnenburg, Hongjun Zheng, Payal Joglekar, steven K. Higginbottom, Susan J. Firbank, David N. Bolam*, Justin L. Sonnenburg*

Highlights

• B. theta's fructan utilization locus encodes proteins with β2-6-linkage specificity
• B. theta's hybrid-two component sensor binds fructose which induces locus expression
• Genome sequence predicts fructan specificity (β2-1 versus β2-6) in Bacteroides species
• Bacteroides species fructan specificity dictates success in β2-1 fructan fed mice

Summary

The intestinal microbiota impacts many facets of human health and is associated with human diseases. Diet impacts microbiota composition, yet mechanisms that link dietary changes to microbiota alterations remain ill-defined. Here we elucidate the basis of Bacteroides proliferation in response to fructans, a class of fructose-based dietary polysaccharides. Structural and genetic analysis disclosed a fructose-binding, hybrid two-component signaling sensor that controls the fructan utilization locus in Bacteroides thetaiotaomicron. Gene content of this locus differs among Bacteroides species and dictates the specificity and breadth of utilizable fructans. BT1760, an extracellular β2-6 endo-fructanase, distinguishes B. thetaiotaomicron genetically and functionally, and enables the use of the β2-6-linked fructan levan. The genetic and functional differences between Bacteroides species are predictive of in vivo competitiveness in the presence of dietary fructans. Gene sequences that distinguish species' metabolic capacity serve as potential biomarkers in microbiomic datasets to enable rational manipulation of the microbiota via diet.

* corresponding authors 

CELL article and link to pdf

David Bolam staff profile

Susan Firbank staff profile