Reactivation of apo liver alcohol dehydrogenase with lead, mercury and cadmium

Liver alcohol dehydrogenase is a dimer of 80,000 M sub(r) with one structural and one catalytic zinc atom per subunit. It is possible to substitute either one or both zinc atoms by different methods. Within each liver alcohol dehydrogenase molecule, there are 2 subunits, 2 active sites and 4 zinc atoms, 2 catalytic (c) and 2 structural or non catalytic (n). The native enzyme is consequently written Zn(c) sub(2)Zn(n) sub(2). Removal of metal is designated by apo. Thus apo(c) sub(2)Zn(n) sub(2) represents enzyme with the catalytic zinc atoms removed. It is often most convenient to make the "hybrid-enzyme", Me(c) sub(2)Zn(n) sub(2), from the "apohybrid", apo(c) sub(2)Zn(n) sub(2), since this is more stable than the fully depleted enzyme, apo(c) sub(2)apo(n) sub(2). The authors show that activity can be restored to dissolved apo liver alcohol dehydrogenase, apo(c) sub(2)Zn(N) sub(2), with the heavy metals cadmium, mercury and lead.