A Human Gut Commensal Ferments Cranberry Carbohydrates to Produce Formate

Authors

Ezgi Özcan, University of Massachusetts AmherstFollow
Jiadong Sun, University of Rhode Island
David C. Rowley, University of Massachusetts Medical School
David A. Sela, University of Massachusetts AmherstFollow

Publication Date

2017

Journal or Book Title

Applied and Environmental Microbiology

Abstract

Commensal bifidobacteria colonize the human gastrointestinal tract and catabolize glycans that are impervious to host digestion. Accordingly, Bifidobacterium longum typically secretes acetate and lactate as fermentative end products. This study tested the hypothesis that B. longum utilizes cranberry-derived xyloglucans in a strain-dependent manner. Interestingly, the B. longum strain that efficiently utilizes cranberry xyloglucans secretes 2.0 to 2.5 mol of acetate-lactate. The 1.5 acetate:lactate ratio theoretical yield obtained in hexose fermentations shifts during xyloglucan metabolism. Accordingly, this metabolic shift is characterized by increased acetate and formate production at the expense of lactate. α-L-Arabinofuranosidase, an arabinan endo-1,5-α-L-arabinosidase, and a β-xylosidase with a carbohydrate substrate-binding protein and carbohydrate ABC transporter membrane proteins are upregulated (>2-fold change), which suggests carbon flux through this catabolic pathway. Finally, syntrophic interactions occurred with strains that utilize carbohydrate products derived from initial degradation from heterologous bacteria.

Comments

Copyright © American Society for Microbiology, Applied and Environmental Microbiology, v.83, 2017.

DOI

10.1128/AEM.01097-17

Volume

83

Issue

17

License

UMass Amherst Open Access Policy

Recommended Citation

Özcan, Ezgi; Sun, Jiadong; Rowley, David C.; and Sela, David A., "A Human Gut Commensal Ferments Cranberry Carbohydrates to Produce Formate" (2017). Applied and Environmental Microbiology. 7.
10.1128/AEM.01097-17