[Screening of a triazophos-degrading strain and pathway of its degradation]

A Triazophos-degrading strain, Klebsiella sp. E6, was identified by soil enrichment technology from the soil sampled from the vicinity of a factory manufacturing Triazophos (TAP). The nutrient requirement of the strain is simple. It can use TAP as the sole sources of carbon, nitrogen and phosphorus. Comparison of the degradation rates revealed that the strain degraded TAP most effectively when TAP was used as a sole nitrogen source. No inhibition effect occurred when TAP concentration was high as 1000 mg/L in the case of TAP was used as the sole nitrogen source. Analysis of the intermediates of TAP metabolism indicated that TAP is firstly hydrolyzed into 1-phenyl-3-hydroxy-1,2,4-triazole and O,O-diethyl phosphorothioic acid. 1-phenyl-3-hydroxy-1,2,4-triazole was further mineralized into inorganic compounds. A degradation pathway of TAP was proposed. The experiment results demonstrated that the strain has potential in biodegradation of TAP pollutions.