title: An insect herbivore microbiome with high plant biomass-degrading capacity.
abstract: Herbivores can gain indirect access to recalcitrant carbon present in plant cell walls through symbiotic associations with lignocellulolytic microbes. A paradigmatic example is the leaf-cutter ant (Tribe: Attini), which uses fresh leaves to cultivate a fungus for food in specialized gardens. Using a combination of sugar composition analyses, metagenomics, and whole-genome sequencing, we reveal that the fungus garden microbiome of leaf-cutter ants is composed of a diverse community of bacteria with high plant biomass-degrading capacity. Comparison of this microbiome's predicted carbohydrate-degrading enzyme profile with other metagenomes shows closest similarity to the bovine rumen, indicating evolutionary convergence of plant biomass degrading potential between two important herbivorous animals. Genomic and physiological characterization of two dominant bacteria in the fungus garden microbiome provides evidence of their capacity to degrade cellulose. Given the recent interest in cellulosic biofuels, understanding how large-scale and rapid plant biomass degradation occurs in a highly evolved insect herbivore is of particular relevance for bioenergy.
authors.affiliation: Department of Energy Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America.
authors.forename: Garret
authors.initials: G
authors.lastname: Suen
authors.forename: Jarrod J
authors.initials: JJ
authors.lastname: Scott
authors.forename: Frank O
authors.initials: FO
authors.lastname: Aylward
authors.forename: Sandra M
authors.initials: SM
authors.lastname: Adams
authors.forename: Susannah G
authors.initials: SG
authors.lastname: Tringe
authors.forename: Adrián A
authors.initials: AA
authors.lastname: Pinto-Tomás
authors.forename: Clifton E
authors.initials: CE
authors.lastname: Foster
authors.forename: Markus
authors.initials: M
authors.lastname: Pauly
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Weimer
authors.forename: Kerrie W
authors.initials: KW
authors.lastname: Barry
authors.forename: Lynne A
authors.initials: LA
authors.lastname: Goodwin
authors.forename: Pascal
authors.initials: P
authors.lastname: Bouffard
authors.forename: Lewyn
authors.initials: L
authors.lastname: Li
authors.forename: Jolene
authors.initials: J
authors.lastname: Osterberger
authors.forename: Timothy T
authors.initials: TT
authors.lastname: Harkins
authors.forename: Steven C
authors.initials: SC
authors.lastname: Slater
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Donohue
authors.forename: Cameron R
authors.initials: CR
authors.lastname: Currie
mesh_terms: D000818:Animals; D001000:Ants / Q000382:microbiology*; D018533:Biomass; D001704:Biopolymers / Q000378:metabolism; D050260:Carbohydrate Metabolism / Q000235:genetics; D002417:Cattle; D016000:Cluster Analysis; D005247:Feeding Behavior / Q000502:physiology*; D005658:Fungi / Q000235:genetics*; D054892:Metagenome / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D018515:Plant Leaves / Q000378:metabolism*
chemical_list: D001704:Biopolymers