Pseudomonas has a plasmid containing the mer operon which includes the gene for mercuric reductase. This enzyme catalyzes the reduction of the mercuric ion hg2+ to the uncharged form of the mercury,hg0. Hg2+ is quite toxic to cells;Hg0 is not.
A) What do you suppose is the inducer for this operon?
B) The proteins encoded by one of the mer genes binds Hg2+ in the periplasm and brings it into the cell. Why would a cell bring in a toxin?
C) What is the value of the mer operon to pseudomonas?