Characterization of arsenic-resistant endophytic bacteria associated with plant grown on mine tailings

摘要

The As resistant plants may harbor microbial communities able to detoxify As. Until now, there is no report about the diversity and As transforming ability of the endophytic bacteria in Mexico. Thirty As resistant bacteria were isolated from the roots of P. laevigata and S. angustifolia grown on the mine tailings in Villa de la Paz, SLP,Mexico. These isolates were identified into eight genera within three phyla (mainly Firmicutes and Actinobacteria). These bacteria showed a high resistance to As: 100 mM to As~(5+) and 50 mM to As~(3+).Some of them presented PGP characteristics. Twenty-one strains were able to transform As on CDM. Therefore, the two sampled plants harbored endophytic bacteria with high As resistance, which could transform As and produced siderophore at the presence of As~(3+) and/or As~(5+). These bacteria have potential in the remediation of the As contaminated sites and worthy for further study.