Arsenic (As) is a well-known toxic metalloid which has found its way to ground waters in many parts of the world, causing severe health problems. As-resistant bacteria are environment friendly tools to remediate such problems. In this study, As(V) resistant bacteria were isolated from industrial site of Kasur, Pakistan. 16S rDNA sequencing revealed the identification of isolates S1 and S5 as Bacillus sub-tilis and Bacillus cereus, respectively. Isolates B. subtilis S1, S2 and S8 were able to resist 1.0mM Zn, Co, Ni, Pb, Cu and 0.1mM Cr and Hg. Bacterial isolates S2, B. cereus S5, S7 and S8 were able to resist As(V) up to 100mM. Maximum As(V)-reduction was shown by B. cereus S5, up to 837.6^M (83.7). Maximum As(III) oxidation was exhibited by B. subtilis S1, up to 122.44^M (24.4). The bacterial isolates were also found to produce biosurfactants, and maximum emulsification index (up to 37.5) was shown by bacterial isolate B. subtilis S1. Such bacteria are potential candidates for bioremediation purposes of sites contaminated with variety of industrial effluents.
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