title: Bacterial protection of beetle-fungus mutualism.
abstract: Host-microbe symbioses play a critical role in the evolution of biological diversity and complexity. In a notably intricate system, southern pine beetles use symbiotic fungi to help overcome host-tree defenses and to provide nutrition for their larvae. We show that this beetle-fungal mutualism is chemically mediated by a bacterially produced polyunsaturated peroxide. The molecule's selective toxicity toward the beetle's fungal antagonist, combined with the prevalence and localization of its bacterial source, indicates an insect-microbe association that is both mutualistic and coevolved. This unexpected finding in a well-studied system indicates that mutualistic associations between insects and antibiotic-producing bacteria are more common than currently recognized and that identifying their small-molecule mediators can provide a powerful search strategy for therapeutically useful antimicrobial compounds.
authors.affiliation: Department of Bacteriology, University of Wisconsin-Madison, WI 53706, USA.
authors.forename: Jarrod J
authors.initials: JJ
authors.lastname: Scott
authors.forename: Dong-Chan
authors.initials: DC
authors.lastname: Oh
authors.forename: M Cetin
authors.initials: MC
authors.lastname: Yuceer
authors.forename: Kier D
authors.initials: KD
authors.lastname: Klepzig
authors.forename: Jon
authors.initials: J
authors.lastname: Clardy
authors.forename: Cameron R
authors.initials: CR
authors.lastname: Currie
mesh_terms: D000085:Acetates / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D039903:Actinobacteria / Q000302:isolation & purification / Q000378:metabolism*; D000364:Agaricus; D000818:Animals; D000898:Antibiosis; D000935:Antifungal Agents / Q000096:biosynthesis* / Q000737:chemistry / Q000494:pharmacology; D001203:Ascomycota / Q000502:physiology*; D001487:Basidiomycota / Q000502:physiology*; D005075:Biological Evolution; D001517:Coleoptera / Q000254:growth & development / Q000382:microbiology* / Q000502:physiology; D007814:Larva / Q000254:growth & development / Q000382:microbiology; D010545:Peroxides / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D028223:Pinus / Q000382:microbiology; D013559:Symbiosis
chemical_list: D000085:Acetates; D000935:Antifungal Agents; D010545:Peroxides; C532356:mycangimycin