农药2,4-滴丁酯与敌敌畏降解菌株的筛选及性能研究

Identification and Degradation of a Bacterium LT1 in Degrading Pesticide 2,4-D Butyl Ester and DDVP

通过以单一农药为碳源的选择性培养基驯化,从农药厂污水处理池活性污泥中筛选出一株能够降解有机氯农药2,4-滴丁酯和有机磷农药敌敌畏的菌株,根据菌株的形态、生理生化特征、16SrRNA序列分析,确定为假单胞菌(Pseudomonas sp.LT1).研究表明,该菌株最适生长温度为30℃,最适生长pH为7.2,对2,4-滴丁酯和敌敌畏的理想降解起始质量浓度为300mg/L;在以2,4-滴丁酯和敌敌畏为唯一碳源的无机盐培养基条件下其降解率分别为93.82%和95.65%,对土壤中的2,4-滴丁酯和敌敌畏的降解率分别为96.20%和97.06%.菌株Pseudomonas sp.LT1对2,4-滴丁酯和敌敌畏的降解酶基因位于基因组上.

The sample was taken from active sludge of pesticide plant treatment tank,and a degradation strains were isolated from it with selective medium with a single pesticide as a carbon source. The degrada- tion strains has a capable of degrading 2,4-D butyl ester and DDVP efficiently. It was initially identified as Pseudomonas sp. （Named as Pseudomonas sp. LT1 ） with the colony observation,physiological and bio- chemical features and 16S rRNA sequence. The research shows that the optimum growth temperature of it was 30℃ and the optimum growth pH was 7.2, the initial concentration of 2,4-D butyl ester and DDVP was 300 mg/L respectively. Under the condition of inorganic salt medium including 2,4-D butyl ester and DDVP as the sole carbon source, The rates of the strains to degrade 2,4-D butyl ester and DDVP were 93.82%和 95.65% respectively and the degradation rates of 2,4-D butyl ester and DDVP were 93.82%和 95.65% in the soil, respectively. Then the degrading gene of strain LT1 was studied preliminarily,the re- sults showed that the degrading gene of 2,4-D butyl ester and DDVP in strain LT1 was located on its ge- nome.