title: The Enterobacterium Trabulsiella odontotermitis Presents Novel Adaptations Related to Its Association with Fungus-Growing Termites.
abstract: Fungus-growing termites rely on symbiotic microorganisms to help break down plant material and to obtain nutrients. Their fungal cultivar, Termitomyces, is the main plant degrader and food source for the termites, while gut bacteria complement Termitomyces in the degradation of foodstuffs, fixation of nitrogen, and metabolism of amino acids and sugars. Due to the community complexity and because these typically anaerobic bacteria can rarely be cultured, little is known about the physiological capabilities of individual bacterial members of the gut communities and their associations with the termite host. The bacterium Trabulsiella odontotermitis is associated with fungus-growing termites, but this genus is generally understudied, with only two described species. Taking diverse approaches, we obtained a solid phylogenetic placement of T. odontotermitis among the Enterobacteriaceae, investigated the physiology and enzymatic profiles of T. odontotermitis isolates, determined the localization of the bacterium in the termite gut, compared draft genomes of two T. odontotermitis isolates to those of their close relatives, and examined the expression of genes relevant to host colonization and putative symbiont functions. Our findings support the hypothesis that T. odontotermitis is a facultative symbiont mainly located in the paunch compartment of the gut, with possible roles in carbohydrate metabolism and aflatoxin degradation, while displaying adaptations to association with the termite host, such as expressing genes for a type VI secretion system which has been demonstrated to assist bacterial competition, colonization, and survival within hosts.
authors.affiliation: Centre for Social Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark Sapountzis@bio.ku.dk.
authors.forename: Panagiotis
authors.identifier: http://orcid.org/0000-0001-6286-3918
authors.initials: P
authors.lastname: Sapountzis
authors.affiliation: Centre for Social Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark Utrecht University, Faculty of Beta-Sciences, Department of Biology, Fungal Physiology Group, Utrecht, The Netherlands.
authors.forename: Thijs
authors.initials: T
authors.lastname: Gruntjes
authors.affiliation: Centre for Social Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Saria
authors.initials: S
authors.lastname: Otani
authors.affiliation: Centre for Social Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark Department of Biology, University of Puget Sound, Tacoma, Washington, USA.
authors.forename: James
authors.initials: J
authors.lastname: Estevez
authors.affiliation: Centre for Social Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Rafael R
authors.initials: RR
authors.lastname: da Costa
authors.affiliation: Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin, USA.
authors.forename: Guy
authors.initials: G
authors.lastname: Plunkett
authors.affiliation: Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin, USA.
authors.forename: Nicole T
authors.initials: NT
authors.lastname: Perna
authors.affiliation: Centre for Social Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Michael
authors.initials: M
authors.lastname: Poulsen
mesh_terms: D000818:Animals; D004755:Enterobacteriaceae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D000069196:Gastrointestinal Microbiome; D016681:Genome, Fungal; D020049:Isoptera / Q000382:microbiology* / Q000502:physiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D013559:Symbiosis; D055434:Termitomyces / Q000145:classification / Q000235:genetics / Q000254:growth & development* / Q000502:physiology