A lead-specific binding protein, PbrR, from the lead resistance operon, pbr, of Cupriavidus metallidurans CH34was incorporated into E. coli in conjunction with an engineered downstream RFP (red fluorescence protein), which allowed for highly sensitive and selective whole-cell detection of lead ions. The subsequent display of PbrR on the E. coli cell surface permitted selective adsorption of lead ions from media containing various heavy metal ions. The surface-engineered E. coli bacteria effectiv-ely protected Arabidopsis thaliana seed germination from the toxicity of lead ions at high concentrations. Engineering the E. coli bacteria harbouring these lead-specific elements from the pbr operon may potentially be a valuable general strategy for biode-tection and bioremediation of toxic heavy metal ions in the environment. |