甲苯降解菌JB-1的分离、鉴定与降解特性

Isolation,Identification and Characteristics of a Toluene-degrading Bacterium JB-1

从南京石化废水处理池的活性污泥中分离到1株能以甲苯为唯一碳源生长的细菌,命名为JB-1.根据其生理生化特征和16SrDNA(GenBank Accession No. EU869278)序列相似性分析,将该菌株鉴定为假单胞菌属(Pseudomonas sp.).该菌株在18h内能完全降解346.4mg/L的甲苯.降解甲苯的最适温度为30℃,pH为7.0,降解速率与初始接种量呈正相关.甲苯降解途径是通过甲苯双加氧酶形成顺甲苯二氢二醇,再经邻苯二酚2,3双加氧酶开环降解.

A bacterial strain JB-1 capable of utilizing toluene as sole carbon source was isolated from active sludge collected from Nanjing Petro-chemical Co.,Ltd.It was preliminarily identified as Pseudomonas sp.according to its physiological and biochemical properties and the similarity analysis of its 16S rRNA gene sequence（GenBank Accession No.EF869278）.Strain JB-1 could degrade 346.4 mg/L toluene within 18 h.The optimal pH and temperature for the degradation were 7.0 and 30 ℃,respectively.The degrading rate showed a positive correlation with the initial inoculum size.The biodegradation pathway of toluene has formed cis-toluene dihydrodiol by toluene dioxygenase.