Isolation, identification and characterization of arsenic transforming exogenous endophytic sp. RPT from roots of .

The aim of the present study was to assess the arsenic (As) transformation potential of endophytic bacteria isolated from roots of plant. The endophytic bacterium was tested for minimal inhibitory concentration (MIC) against As. The endophytic strain RPT exhibited the highest resistance to As(V) (400 mg/l). Phylogenetic analysis of the 16S rRNA sequence suggested that strain RPT was a member of genus . The As transformation assay revealed As(III) oxidation and As(V) reduction potential of sp. RPT. The As resistance mechanism was further confirmed by amplification of and genes. The growth kinetics of strain RPT was altered slightly in the presence of different concentration (100-400 mg/l) of As stress. Temperature and pH influenced the As removal rate. The maximum As removal was observed at pH 7.0 (74%) and 37 °C (70.9%). The results suggest that strain RPT can survive under the As stress and has been identified as a potential candidate for application in bioremediation of As in contaminated environments.