Isolation of a buprofezin co-metabolizing strain of Pseudomonas sp. DFS35-4 and identification of the buprofezin transformation pathway

Abstract

Buprofezin is a widely used insecticide that has caused environmental pollution in many areas. However, biodegradation of buprofezin by pure cultures has not been extensively studied, and the transformation pathway of buprofezin remains unclear. In this paper, a buprofezin co-metabolizing strain of DFS35-4 was isolated from a buprofezin-polluted soil in China. Strain DFS35-4 was preliminarily identified as Pseudomonas sp. based on its morphological, physiological, and biochemical properties, as well as 16S rRNA gene analysis. In the presence of 2.0 g l(-1) sodium citrate, strain DFS35-4 degraded over 70% of 50 mg l(-1) buprofezin in 3 days. Strain DFS35-4 efficiently degraded buprofezin in the pH range of 5.0-10.0 and at temperatures between 20 and 30°C. Three metabolites, 2-imino-5-phenyl-3-(propan-2-yl)-1,3,5-thiadiazinan-4-one, 2-imino-5-phenyl-1,3,5-thiadiazinan-4-one, and methyl(phenyl) carbamic acid, were identified during the degradation of buprofezin using gas chromatography-mass spectrometry (GC-MS) and tandem mass spectrometry (MS/MS). A partial transformation pathway of buprofezin in Pseudomonas sp. DFS35-4 was proposed based on these metabolites.

Biodegradation of Buprofezin by Rhodococcus sp. Strain YL-1 Isolated from Rice Field Soil

“…On the basis of above results, we propose a transformation pathway for buprofezin in Rhodococcus sp. YL-1 (Figure ); this proposed pathway is completely different from the cometabolizing pathway in strain DFS35-4 . The benzenic ring is first removed from buprofezin to generate catechol and 2- tert -butylimino-3-isopropyl-1,3,5-thiadiazinan-4-one, and the latter is then transformed into N - tert -butyl-thioformimidic acid formylaminomethyl ester, followed by conversion into 2-isothiocyanato-2-methyl-propane; 2-isothiocyanato-2-methyl-propane is subsequently degraded into 2-isothiocyanato-propane through partial C-dealkylation.…”

“…Microbes play an important role in removing toxic substances from the environment, and microbial bioremediation is considered to be a cost-effective tool for the detoxification of xenobiotics . Previously, two bacterial strains that are able to cometabolize buprofezin have been reported. , …”

Functional Characterization and Genomic Analysis of the Chlorantraniliprole-Degrading Strain Pseudomonas Sp. GW13

“…on the basis of the morphological characteristics, physico-biochemical characteristics and 16S rRNA gene analysis. In a previous study, the genus Pseudomonas is a valuable resource for degrading pesticides in the environment, such as ethametsulfuron-methyl, imazethapyr, buprofezin, chlorothalonil, o-nitriobenzaldehyde, and phenol [23][24][25][26][27][28]. Additionally, strain RPT 52, which is capable of degrading imidacloprid, endosulfan and coragen, also belongs to the genus Pseudomonas [12].…”

Response Surface Methodology for the Optimization of Chlorpyrifos-Degrading Conditions by Pseudomonas stutzeri ZH-1

“…To explore the effect of the oscillator speed on chlorpyrifosdegrading, the oscillator speed was controlled at 0, 40, 80, 120, 160 or 200 rpm. For all experiments, cells were inoculated at 2% (v/v) into cultures of pH 7.0, then they were incubated at 37˚C on a shaker at 140 rpm for 5 days unless otherwise stated [11].…”