三唑磷降解菌的筛选及其降解途径研究

从三唑磷生产厂周围的土壤中用土壤富集的方法筛选分离出一株三唑磷降解菌Klebsiella sp.，它能以三唑磷为唯一碳源、唯一氮源、唯一磷源生长同时实现对三唑磷的降解，三唑磷作为唯一氮源时的降解速度最快，是实现三唑磷降解的最佳营养方案。在三唑磷为唯一氮源时，1000 mg/L的三唑磷浓度对菌体降解无抑制作用。此降解菌首先通过水解作用实现对TAP 的降解，之后把水解产物进一步降解为无毒的无机物质。降解菌的这些降解特性表明了它用于生物降解消除三唑磷污染的巨大潜力。

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 1000mg/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.