ERIC-PCR:一种快速鉴别环境细菌菌株的方法

ERIC PCR AS A NEW TOOL FOR QUICK IDENTIFICATION OF ENVIRONMENTAL BACTERIA

以 Ｅ Ｒ Ｉ Ｃ（ 肠杆菌基因间共有重多序列） 序列设计的特异引物对３ 株大肠杆菌、３ 株软腐欧氏杆菌、２ 株草生欧氏杆菌、１ 株梨火疫欧氏杆菌、１ 株催娩克氏菌、１ 株阴沟肠杆菌和９ 株具有降酚能力的细菌等２０ 种细菌的基因组 Ｄ Ｎ Ａ 进行 Ｐ Ｃ Ｒ 分析．每种菌株均存在数目不等的各自独特的带型，能够区分同一种类中极为相近的菌株．经多次重复，各特异性扩增的主要带型能重复稳定出现．聚类分析的结果表明，供试菌株多数按照分类地位归到相应的组中．９ 种具有降酚能力的细菌中，２ 种分离自处理焦化废水池活性污泥，７ 种来自土壤样品． Ｅ Ｒ Ｉ Ｃ Ｐ Ｃ Ｒ 指纹图显示，前２ 种属于一类，都有一条大小约１ ．１ ｋｂ 的主带，其它７ 种土壤中分离出来的细菌除其中１ 种有１ 条约１ ．２ ｋｂ 大小的主带外，其余６ 种都有１ 条大小约１ ．４ ｋｂ 的带．聚类分析将从土壤中分离出来的细菌归为３ 种不同的类型． Ｅ Ｒ Ｉ Ｃ Ｐ Ｃ Ｒ 可以从分子水平对细菌基因组进行快速指纹图分析。

ERIC (Enterobacterial Repetitive Intergenic Consensus) sequence is a kind of dispersed repetitive DNA sequence found in the genome of eubacteria. Genomic DNA of 20 different bacterial strains including 3 Escherichia coli , 3 Erwinia carotovora , 2 E. herbicola , 1 E. amylovora , 1 Klebs oxytoca , 1 Enterobacter cloacae and 9 phenol degrading bacteria were amplified and analyzed by PCR with primers specific for ERIC sequence. Each strain showed different profile of band patterns when PCR products were analyzed in agarose gel electrophoresis. The strains of the same species were resolved by unique bands specific for each strain. Distinctive band patterns of the strains were repeatable among different batches of experiments. Two of the 9 phenol degrading bacteria were isolated from activated sludge for treating the wastewater from coke industry, while the rest from soil samples. The 2 strains from a coke plant showed one major band of 1.1 kb in ERIC PCR. One of the 7 soil strains had one 1.2 kb band and the other 6 soil strains gave one common band of 1.4 kb long as main band. Based on ERIC PCR patterns, the 7 soil isolates were classified into 3 groups by cluster analysis. The analysis of genomic DNA by ERIC PCR is thus a practical method for fingerprinting of genomic DNA, which can be used for quick identification and classification of the bacteria from different environmental samples.