Bacteria expressing metallothionein gene into the periplasmic space, and

Abstract

A gene coding for the expression of metallothionein is incorporated into an xpression vehicle for expressing the metallothionein gene into the periplasmic space of a bacterium including the expression vehicle. It may also be possible to incorporate multiple copies of the metallothionein gene within a single bacterium. One typical expression vehicle is a p-MalP plasmid constructed to include the metallothionein gene. Using this expression vehicle, one can induce bacteria, such as transformed E. coli, to express metallothionein into the periplasmic space as a fusion product with, for example, the maltose-binding protein. Killed cell that have expressed metallothionein into the periplasmic space may then be attached to a solid support. The resulting device may be used to remove heavy metals from aqueous media.