Enigmatic behavior of bacillus licheniformis das-2 in mitigating the arsenic (as) contaminated region of Eastern India

Bihar state (Part of eastern India) is a part of Bengal Delta located at 85º 32’ E and 25º 11’ N latitude of the earth. This region is less industrialized and 70% of the people are dependent for their livelihood on agriculture. The major source of irrigation is contaminated underground water, so form of Arsenic passes through food chain to human beings. This is through both primary and secondary production. Chakraborti et. al., 2004 had reported adverse effect of Arsenic in the form of skin lesion and neurological disorder from the people of Simaria ojha-patti(a village) of Bihar state. B.licheniformis DAS-2 also degrades the different types of waste product and shows both reductase as well as keratinolytic activity. The above enigmatic property of this rhizospheric bacteria is that it converts more toxic form of pentavalent Arsenic (AsV) such as arsenate to less toxic form of trivalent Arsenic (AsIII) called as arsenite because it secretes an enzyme arsenate reductase. Although this bacterial strain also shows keratinolytic properties. It degrades the the keratin containing animal waste product such as feather, hairs, hoofs, Nails etc. Since keratin protein is essential for the making cosmetics, leather industry. Feather waste is a major animal food stuff polluted the environment that is degraded by B.licheniformis DAS-2. Eventhough it is mesophilic, gram positive, nonpathogenic, rhizospheric in nature but it shows above unique properties. So this is the novel characteristics of this bacterial strain. Soil with long term exposure of As (V) and As (III) may result in this evolution of diverse arsenic resistant strains. Relative abundance of different form (III and V) in the soil is influenced by microbial transformations. Transformation of arsenic in different chemical species might be the best survival strategy of soil bacteria in arsenic contaminated environment. So it may concluded that this bacterial strain involved in enigma of toxic environment.