RT Journal Article
SR Electronic
T1 The structured diversity of specialized gut symbionts of the New World army ants
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 084376
DO 10.1101/084376
A1 Piotr Łukasik
A1 Justin A. Newton
A1 Jon G. Sanders
A1 Yi Hu
A1 Corrie S. Moreau
A1 Daniel J. C. Kronauer
A1 Sean O’Donnell
A1 Ryuichi Koga
A1 Jacob A. Russell
YR 2016
UL http://biorxiv.org/content/early/2016/10/30/084376.abstract
AB Symbiotic bacteria play important roles in the biology of their arthropod hosts. Yet the microbiota of many diverse and influential groups remain understudied, resulting in a paucity of information on the fidelities and histories of these associations. Motivated by prior findings from a smaller scale, 16S rRNA-based study, we conducted a broad phylogenetic and geographical survey of microbial communities in the ecologically dominant New World army ants (Formicidae: Dorylinae). Amplicon sequencing of the 16S rRNA gene across 28 species spanning the five New World genera showed that the microbial communities of army ants consist of very few common and abundant bacterial species. The two most abundant microbes, referred to as Unclassified Firmicutes and Unclassified Entomoplasmatales, appear to be specialized army ant associates that dominate microbial communities in the gut lumen of three host genera, Eciton, Labidus and Nomamyrmex. Both are present in other army ant genera, including those from the Old World, suggesting that army ant symbioses date back to the Cretaceous. Extensive sequencing of bacterial protein-coding genes revealed multiple strains of these symbionts co-existing within colonies, but seldom within the same individual ant. Bacterial strains formed multiple host species-specific lineages on phylogenies, which often grouped strains from distant geographic locations. These patterns deviate from those seen in other social insects, and raise intriguing questions about the influence of army ant colony swarm-founding and within-colony genetic diversity on strain co-existence, and the effects of hosting a diverse suite of symbiont strains on colony ecology.