Site of action of metals on the aminolevulinic acid dehydratase of human erythrocytes.

The site of action of four metals (copper, lead, nickel and zinc) on the aminolevulinic acid dehydratase of human erythrocytes was studied. Data obtained after denaturation of allosteric sites with heat treatment and after simultaneous incubation with two metals suggest the following conclusions: copper acts on the catalytic site, whereas lead, nickel and zinc act on the allosteric sites; zinc and nickel act on the same allosteric (metallic) site; zinc and lead only partially act on the same metallic site; nickel and lead act on different allosteric sites.