Skip to Main content Skip to Navigation
Journal articles

Functional Diversity of Carbohydrate-Active Enzymes Enabling a Bacterium to Ferment Plant Biomass

Abstract : Microbial metabolism of plant polysaccharides is an important part of environmental carbon cycling, human nutrition, and industrial processes based on cellulosic bioconversion. Here we demonstrate a broadly applicable method to analyze how microbes catabolize plant polysaccharides that integrates carbohydrate-active enzyme (CAZyme) assays, RNA sequencing (RNA-seq), and anaerobic growth screening. We apply this method to study how the bacterium Clostridium phytofermentans ferments plant biomass components including glucans, mannans, xylans, galactans, pectins, and arabinans. These polysaccharides are fermented with variable efficiencies, and diauxies prioritize metabolism of preferred substrates. Strand-specific RNA-seq reveals how this bacterium responds to polysaccharides by up-regulating specific groups of CAZymes, transporters, and enzymes to metabolize the constituent sugars. Fifty-six up-regulated CAZymes were purified, and their activities show most polysaccharides are degraded by multiple enzymes, often from the same family, but with divergent rates, specificities, and cellular localizations. CAZymes were then tested in combination to identify synergies between enzymes acting on the same substrate with different catalytic mechanisms. We discuss how these results advance our understanding of how microbes degrade and metabolize plant biomass.
Document type :
Journal articles
Complete list of metadatas

Cited literature [63 references]  Display  Hide  Download

https://hal-cea.archives-ouvertes.fr/cea-01138771
Contributor : Bruno Savelli <>
Submitted on : Thursday, April 2, 2015 - 4:05:57 PM
Last modification on : Wednesday, June 17, 2020 - 3:42:03 PM
Long-term archiving on: : Friday, July 3, 2015 - 10:41:30 AM

Files

journal.pgen.1004773 (1).pdf
Publisher files allowed on an open archive

Identifiers

Citation

Magali Boutard, Tristan Cerisy, Pierre-Yves Nogue, Adriana Alberti, Jean Weissenbach, et al.. Functional Diversity of Carbohydrate-Active Enzymes Enabling a Bacterium to Ferment Plant Biomass . PLoS Genetics, Public Library of Science, 2014, pp.1004773. ⟨10.1371/journal.pgen.1004773⟩. ⟨cea-01138771⟩

Share

Metrics