Isolation and Molecular Characterization of Arsenic Resistant Bacteria from Brahmaputra River Basin of Assam, India

From the earliest detection of arsenic in the Brahmaputra basin back in 2004, several districts of Assam especially in the flood plains have joined the list of arsenic contamination. Lakhimpur district in Assam India, has been recorded with arsenic concentration several folds higher than the WHO and BIS recommendations. Scientific reports emphasize how native microorganisms can modulate the biogeochemical cycle of arsenic and their possible application in bioremediation. With the aim, this study was designed to isolate and carry out taxonomic characterization of arsenic resistant bacteria from potable water sources of the district. Based on the minimum inhibitory concentration test, two isolates LB6 and NB14 showing the highest resistance were characterized both by biochemical and molecular methods. Morphogenetic characterization identified the strains like Escherichia coli -LB6 and Acinetobacter baumannii -NB14. Taxonomic identification was further validated by fatty acid methyl ester analysis. This data of the entire study can conclude that two potential strains E.coli-LB6 and Acinetobacter baumannii-NB14 can resistant arsenic As V (100 to 200mM) and As III (10 to 50mM) concentration in the medium. The results further suggest that strains, LB6, and NB14 can survive under the arsenic stress and has been identified as a potential candidate for application in bioremediation field.