Study of thermal and acid denaturation of DNA by means of voltammetry at graphite electrodes

✍ Scribed by Viktor Brabec

• Publisher: Wiley (John Wiley & Sons)
• Year: 1979
• Tongue: English
• Weight: 497 KB
• Volume: 18
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.1979.360181003

✦ Synopsis

Abstract

Conformational changes in guanine–cytosine (G·C) and adenine–thymine (A·T) pairs in DNA were investigated by means of differential pulse voltammetry at a pyrolytic graphite electrode (PGE). As a monitor of these conformational changes, two separated voltammetric peaks, G and A, which correspond to electrochemical oxidation at the PGE of guanine and adenine residues, respectively, were used. It was found that peak A was first increased in the course of thermal denaturation of DNA. This indicates that, on heating a native DNA sample, regions rich in A·T pairs melt first. In the course of acid denaturation of a native DNA sample, the height of peak A was changed just before the denaturation. It is suggested that protonation of adenine residues in DNA regions rich in A·T pairs was responsible for these changes.