多环芳烃降解菌ZL5分离鉴定及其降解质粒

ISOLATION AND IDENTIFICATION OF PAHS-DEGRADING STRAIN ZL5 AND ITS DEGRADATIVE PLASMID

通过选择性富集培养 ,从辽河油田石油污染土壤中分离到一株多环芳烃 (PAHs)降解菌ZL5 .它能以菲和芘为唯一碳源生长 ,但是不能利用萘 .16SrDNA核苷酸序列分析结果表明 ,ZL5属于变形细菌α亚类中的鞘氨醇单胞菌属 .该菌株含有一个大小约为 6 0kb的质粒 .丝裂霉素C消除实验表明 ,随着质粒的丢失 ,菌株利用菲和芘的能力也丧失 .用电转化和氯化铷转化法分别将菌株ZL5的质粒导入大肠杆菌JM10 9和DH5α中 ,随着质粒的获得 ,这些转化子获得了降解菲和芘的能力 .本研究结果表明 ,鞘氨醇单胞菌ZL5降解PAHs的功能和质粒有关 .图 4参

Through selective enrichment culture, a PAHs- degrading bacterial strain ZL5 was isolated from oil-contaminated soil in Liaohe Oil Field. The strain was able to use phenanthrene and pyrene as the sole carbon source for growth, but could not utilize naphthalene. The sequence analysis of 16S rDNA showed that ZL5 belongs to Proteobacteria alfa subdivision; Sphingomonas. A plasmid , approximately 60 kb in size, was detected from strain ZL5. The strain lost the ability to degrade phenanthrene and pyrene when its plasmid was eliminated by mitomycin C. The transformants obtained the ability to degrade phenanthrene and pyrene when the plasmid of strain ZL5 was transformed to Escherichia coli JM109 through electroporation and Rbcl transformation. This work indicates that the plasmid of strain ZL5 could be responsible for the degradation of PAHs. Fig 4 , Ref 16