一株高耐镉菌株的分离、鉴定及系统发育分析

Isolation, Identification and Phylogenetic Analysis of a High Cd-resistance Bacterial Strain

采用梯度浓度驯化方法,从极度重金属污染环境的土壤中取样分离、纯化1株具有较强镉耐受性的菌株(编号为LY29-1-5)。经菌落、菌体形态观察、生理生化及系统发育分析,该菌株初步鉴定为大肠杆菌(Escherichia coli)。该菌株能耐受镉离子的最高浓度为15 mmol/L,在最低抑制浓度试验中,该菌株对铅、铜、锌也表现出了一定的耐受性。

A high Cd-resistance strain (No. LY29-1-5) was isolated and purified from extremely heavy metal contaminated soil byacclimation of concentration gradient approach. The strain was identified as Escherichia coli by morphological examination, physiologicaland biochemical characteristics as well as 16S rDNA sequence and phylogenetic analysis. The strain could endure 15 mmol/L maximumconcentration of cadmium (Cd2+). The strain was also proved to have the ability to resist Pb2+, Cu2+, Zn2+ through experiment of minimuminhibitory concentration (MIC).