Isolation and characterization of an Arthrobacter sp. strain HB-5 that transforms atrazine

A bacterial strain (HB-5) capable of utilizing atrazine as sole carbon and nitrogen source for growth was isolated from an industrial wastewater sample by enrichment culture. The isolate was identified as Arthrobacter sp. according to its phenotypic features, physiologic and biochemical characteristics, and phylogenetic analysis. The strain exhibited faster atrazine degradation rates in atrazine-containing mineral media than the well-characterized atrazine-degrading bacteria Pseudomonas sp. ADP. The broad optimum pH and temperature ranges observed for strain HB-5 indicate that it has potential for remediation of atrazine-contaminated sites. Strain HB-5 first metabolizes atrazine to yield hydroxyatrazine. Then, the bacterium metabolizes hydroxyatrazine to cyanuric acid, but could not mineralize atrazine.