Characterization, genome functional analysis, and detoxification of atrazine by Arthrobacter sp. C2

Residual injury of atrazine to the succeeding crops has been frequently reported. It is necessary to find a solution for the detoxification of atrazine contaminated soil. A high-efficient bacterial strain Arthrobacter sp. C2 for atrazine degradation was isolated in this study. The genomic information of the isolate C2, and its degradation characteristics and potential application in detoxification of atrazine contaminated soil were investigated. The results indicated that the isolate C2 genome contained 4,305,216 bp nucleotides, three plasmids, and 4705 coding genes. The degradation rates of atrazine at levels of 1, 10, 100 mg/L by the isolate C2 were 0.34, 1.94, 18.64 mg/L/d, respectively. The optimum temperature and pH for the isolate C2 to degrade atrazine were 30 degrees C and 7.0-9.0. Based on the metabolites detected by UPLC-TOF-MS/MS and genome annotation of the isolate C2, a common metabolic pathway of atrazine was proposed as that atrazine is firstly dechlorinated into hydroxyatrazine, and subsequently to N-isopropylammelide via dealkylation, and ultimately deaminated to cyanuric acid. Introduction of the isolate C2 into soil can enhance degradation of atrazine and thus eliminate the toxic effect of this herbicide on wheat growth. Our results indicate that the strain C2 could be a potential bioresource for bioremediation of atrazine contaminated soil. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The bacterial strain Arthrobacter sp. C2 was isolated for atrazine degradation, showing degradation rates of 0.34, 1.94, and 18.64 mg/L/d at different concentrations. The optimal conditions for degradation were at 30°C and pH 7.0-9.0, and a metabolic pathway for atrazine degradation was proposed. The introduction of strain C2 into soil can enhance atrazine degradation and eliminate its toxic effects on wheat growth.