Characterization of arsenic-resistant endophytic Priestia megaterium R2.5.2 isolated from ferns in an arsenic-contaminated multi-metal mine in Vietnam

Bioremediation is a biological process to remove or neutralize environmental pollutants. This study was carried out investing at the efficacy of arsenic resistant endophytic bacteria isolated from Pteris vittata, Pityrogramma calomelanos, Blenchum orientale, and Nephrolepis exaltata, which grow in highly (As) contamination mining site Vietnam. Their segmented roots, stems, leaves were homogenized separately inoculated on LB agar plates containing 5mM As(III) As(V). A total 31 strains selected, strain R2.5.2 root P. calomelanos had highest capability. Strain tolerated up 320 mM 160 arsenate arsenite, respectively. The developed well media 0.1 5% NaCl, 20-40ºC pH 5 9, actively utilized most sugar sources. It high IAA biosynthesis capacity with an average concentration 19.14 mg/L, 0.5-16 Ag+, Hg2+, Co2+, Ni2+, Cu2+, Cr4+, reduced Based 16s rDNA, identified as Priestia megaterium. ars C gene coding for reductase catalyzing reduction As(V) successfully amplified megaterium R2.5.2. selected may have potential use bioremediation practice.