Enhanced microbial degradation of insecticides in soil

Abstract

Laboratory experiments were conducted to investigate the enhanced degradation of isofenphos (l-methylethyl-2-[[ethoxy[(l-methylethyl)amino]phosphinothioyl]-oxy] benzoate) in soil and to elucidate the microbiology of this phenomenon. [U ring-''^C]Isofenphos was most rapidly degraded in Iowa cornfield soils that had a history of isofenphos insecticide use. Between 13 and 42^ of an applied dose of 5 ppm remained as isofenphos after 4 weeks in soil with isofenphos use history, whereas between 63 and 13% remained in comparable nonhistory soils. Soils with enhanced isofenphos degradation contained an adapted population of soil microorganisms responsible for the degradation observed. Degradation products of isofenphos detected in cultures of adapted soil microorganisms included isopropyl salicylate, ''^COg, and polar products. A bacterial strain (Pseudomonas sp.) isolated from soil with enhanced isofenphos degradation proved capable of utilizing isofenphos as a sole carbon source.

Bioprospecção de genes biossintéticos de policetídeos em DNA metagenômico de solo de Mata Atlântica.

“…Com isso, é possível a caracterização e descoberta de novos genes, enzimas, metabólitos bioativos e fármacos associados à rica diversidade de organismos ainda não-cultivados, bem como, o desenvolvimento de novas estratégias de seleção de novos produtos alvos e ensaios a partir doconhecimento da genômica e expressão gênica de organismos diversos. (Racke, 1990). Em termos de fluxo energético os micro-organismos são os principais responsáveis pela mineralização dos nutrientes, cerca de 90%, tornando-os disponíveis na solução do solo (Lavelle, 2000).…”