title: Symbiotic bacteria on the cuticle of the leaf-cutting ant Acromyrmex subterraneus subterraneus protect workers from attack by entomopathogenic fungi.
abstract: Although only discovered in 1999, the symbiotic filamentous actinobacteria present on the integument of certain species of leaf-cutting ants have been the subject of intense research. These bacteria have been shown to specifically suppress fungal garden parasites by secretion of antibiotics. However, more recently, a wider role for these bacteria has been suggested from research revealing their generalist anti-fungal activity. Here we show, for the first time, evidence for a role of these bacteria in the defence of young worker ants against a fungal entomopathogen. Experimental removal of the bacterial bio-film using an antibiotic resulted in a significant increase in susceptibility of worker ants to infection by the entomopathogenic fungus Metarhizium anisopliae. This is the first direct evidence for the advantage of maintaining a bacterial bio-film on the cuticle as a defensive strategy of the ants themselves and not exclusively for protection of the fungus garden.
authors: Department of Entomology and Plant Pathology, State University of North Fluminense, Rio de Janeiro, Brazil.
authors: Thalles C
authors: TC
authors: Mattoso
authors: Denise D O
authors: DD
authors: Moreira
authors: Richard I
authors: RI
authors: Samuels
mesh_terms: D039903:Actinobacteria / Q000502:physiology*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001000:Ants / Q000382:microbiology* / Q000502:physiology; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D001938:Brazil; D004817:Epidermis / Q000382:microbiology; D052981:Metarhizium / Q000502:physiology*; D013559:Symbiosis
chemical_list: D000900:Anti-Bacterial Agents