Mechanism of the Reaction of Polynucleotides and HgII

Abstract

THE reversible reaction of deoxyribonucleic acid (DNA) and HgII has been known for some nine years1during which it has been studied by a wide variety of techniques1–5. All the studies concur in demonstrating that the binding is quite strong but can nevertheless be completely reversed by a variety of common chemical reagents which complex HgII. After reversal the DNA is both structurally and functionally intact despite the large changes in physical properties which accompany and characterize the reaction. Initially thought to be a reaction which occurred primarily with phosphoryl groups1 it was later convincingly suggested by Thomas2 that the reaction occurred primarily at the bases. A few years later this observation was confirmed and extended to a greater variety of polydeoxyribonucleotides3,5 and most recently to the polyribonucleotide of tobacco mosaic virus6.