The gut microbiota of insecticide-resistant insects houses insecticide-degrading bacteria: A potential source for biotechnological exploitation

• Published in: PloS one Vol. 12; no. 3; p. e0174754
• Main Authors: Almeida, Luis Gustavo de, Moraes, Luiz Alberto Beraldo de, Trigo, José Roberto, Omoto, Celso, Cônsoli, Fernando Luis
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 30-03-2017; Public Library of Science (PLoS)
• Subjects: Agrochemicals; Animals; Bacteria; Bacteria - drug effects; Benzamides - pharmacology; Biodegradation; Biology and Life Sciences; Bioremediation; Biotechnology; Chlorpyrifos; Degradation; Deltamethrin; Drug Combinations; Ecology; Evolution; Exploitation; Gas Chromatography-Mass Spectrometry; Gastrointestinal Microbiome - physiology; Host-parasite interactions; Housing; Insecticide resistance; Insecticides; Insecticides - pharmacology; Insects; Instars; Intestinal microflora; Laboratories; Larvae; Macrolides - pharmacology; Medicine and Health Sciences; Microbiota (Symbiotic organisms); Microorganisms; Nitriles - pharmacology; Pest control; Pesticide resistance; Pesticides; Pyrethrins - pharmacology; Research and Analysis Methods; Residential areas; Selective media; Spodoptera - microbiology; Spodoptera frugiperda; Tandem Mass Spectrometry; Trends
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0174754

The exploration of new niches for microorganisms capable of degrading recalcitrant molecules is still required. We hypothesized the gut microbiota associated with insect-resistant lines carry pesticide degrading bacteria, and predicted they carry bacteria selected to degrade pesticides they were resistant to. We isolated and accessed the pesticide-degrading capacity of gut bacteria from the gut of fifth instars of Spodoptera frugiperda strains resistant to lambda-cyhalothrin, deltamethrin, chlorpyrifos ethyl, spinosad and lufenuron, using insecticide-selective media. Sixteen isolates belonging to 10 phylotypes were obtained, from which four were also associated with the susceptible strain. However, growth of gut bacteria associated with larvae from the susceptible strain was not obtained in any of the insecticide-based selective media tested. Growth of isolates was affected by the concentration of insecticides in the media, and all grew well up to 40 μg/ml. The insecticide-degrading capacity of selected isolates was assessed by GC or LC-MS/MS analyses. In conclusion, resistant strains of S. frugiperda are an excellent reservoir of insecticide-degrading bacteria with bioremediation potential. Moreover, gut-associated bacteria are subjected to the selection pressure imposed by insecticides on their hosts and may influence the metabolization of pesticides in insects.