一株大质粒决定的耐镉假单胞菌的鉴定与耐受性分析

Identification and tolerance analysis of a large plasmid determined cadmium resistance Pseudomonas sp.

摘要: 分离到一株耐镉菌株XZC1,结合菌落特征和16S r DNA序列对其进行鉴定,将该菌在含Cd2+液体LB培养基中进行连续培养,获得菌体生长情况,分析该菌株镉耐性是否与质粒相关,检测菌株对其他几种重金属的耐性。结果表明,该菌株是Pseudomonas sp.,在Cd2+浓度为400mg/L LB培养基中可正常生长;经过质粒消除的XZC1不具有镉耐性,说明该菌株的镉耐性基因存在于大质粒上;XZC1对Fe2+、Cu2+、Mn2+、Ni2+的耐性较强,在400mg/L以上。菌株XZC1在重金属污染防治方面有深入研究价值。

Abstract: A cadmium resistant strain,XZC1,was separated. The strain was identified by colony characteristics and 16 S r DNA sequence. XZC1 was then cultured in liquid LB medium containing Cd2 +to study its growth curve. The relationship between Cd2 +tolerance and plasmid was analyzed. The tolerance of the strain to several other heavy metals was tested. The results show that,the strain was Pseudomonas sp.,it could grow in LB with 400mg/L Cd2 +,after plasmid elimination,XZC1 had no Cd2 +tolerance,indicating that Cd2 +tolerance gene of the strain exists in large plasmid,XZC1 had high tolerance to Fe2 +,Cu2 +,Mn2 +,Ni2 +,which was above400mg/L. The strain was of significant on the research of prevention heavy metal pollution.