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

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.