Proton transfer during DNA strand separation as a source of mutagenic guanine-cytosine tautomers

Abstract

Proton transfer between DNA bases can lead to mutagenic tautomers, but as their lifetimes are thought to be much shorter than DNA separation times their role during the DNA replication cycle is often overlooked. Here, the authors model the separation of the DNA base pair guanine-cytosine using density functional theory and find increased stability of the tautomer when the DNA strands unzip as they enter a helicase enzyme, effectively trapping the tautomer population.