Construction and characterization of Escherichia coli genetically engineered for bioremediation of Hg(2+)-contaminated environments.

Escherichia coli strains were genetically engineered to express an Hg2+ transport system and metallothionein. Overexpression of a glutathione S-transferase fusion protein of Saccharomyces cerevisiae or pea metallothionein significantly increased the bioaccumulation of Hg2+ transported by MerT and MerP and protected the cells from the accumulated Hg2+. The recombinant strains have excellent properties for bioremediation of Hg(2+)-contaminated environments.