Identification and Characterization of a Newly Isolated Carbendazim-degrading Bacterial Strain MBC

A novel bacterial strain,which can effectively use carbendazim as sole carbon and energy source,was isolated from long-term carbendazim administered soil by enrichment screening.Based on the analysis of physiological and biochemical characteristics,16S rDNA gene sequence homology and phylogenetic tree,the isolate was identified.Its degradation characteristics and degradation capability of the lysate were tested by HPLC.The new bacterial strain was identified as Raoultella sp.and named MBC.Results showed that this strain could utilize carbendazim as sole carbon source for growth,and could degrade 100% of carbendazim after 72 h shaking culture at 200 r·min-1,25 ℃ and pH 7.0.Its degradation rate was increased by adding exogenous carbon and nitrogen source into the medium at the later stage of culture,and the degradation of adding exogenous nitrogen source was more effective than that of carbon source.The lysate had a degrading activity of carbendazim,and the catabolic enzymes were the induced enzyme.These results provided a rationale and a material for bio-remediation of long-term carbendazim-contaminated soil.