Saprophytic soil Bacillus subtilis strain NC was isolated from an industrial region, at Shubra Al-Khima, north Cairo, Egypt. A progeny strain was isolated and adapted to metal bioremediation under stress of Cr6+, Hg2+and Fe3+ ions. Both parent (Pt) and progeny (Pg) were treated with separate nine heavy metals. According to their impact upon the bacterial viability, the heavy metals tested were assigned into three groups: Growth promoting elements (GPE) including Mn2+, Co2+, Zn2+ and Mg2+; growth retarding elements (GRE) including Li+, and B3+ and growth inhibiting elements (GIE) including Sr2+, V5+ and Pb2+. Fortifying these groups with traces of Cr6+ (C), Hg2+ (A), and Fe3+ ions (F), separately, resulted in a dissimilar influence on the groups. For the Pg lines, the toxic effect of GRE was antagonized and that of GPE was synergized while the inhibitory effect of GRE was prominent for Pt line. Consumption of heavy metals in the bacterial growth (%of residual control) was the highest with GPE and the least was GIE fortified with C, A and F, indicating the lyses of cells and impairment of permeability control. Pt and Pg proteinomes were subjected to SDS-PAGE analysis. Electrophoretic profile analysis indicated the presence of novel bands expression of regulons in Pg smear emerging the possibility of induction of proteins/enzymes capable of adapting the high concentrations of heavy metals.
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