Hydrogen bonding and DNA: 66-year retrospective (briefly)

Abstract

Background: As Yu.P. Blagoi, the memory of who is dedicated to this work, once said: "The molecular structure of DNA — the famous double helix — is stabilized by water molecules and metal ions". The central, key interaction that determines both the double-helix structure of DNA and its functioning (the genetic code, replication, mutagenesis) is hydrogen-bonded interaction. Objectives: Demonstration of the diverse manifestations of the hydrogen bond in the structure and functioning of DNA. Materials and Methods: A computer simulation based on the density functional method was used. Results: This paper identifies a wide range of hydrogen-bonded interactions that determine key aspects of both DNA structures and functional features related to heredity (replication, mutagenesis). Conclusions: The preopeness of DNA base pairs with an embedded water molecule on the exterior hydrogen bond create more favorable conditions for proton transitions between bases along the central hydrogen bond. In this case, the hydrogen bonds of the bases to a lesser extent hinder the transition of the proton due to the smaller electrostatic repulsion (due to a larger distance) between them. Therefore, the preopened pairs are likely to form tautomeric forms of nucleic acid bases and to originate a probable mechanism for the formation of point mutations in DNA. At the same time, the central hydrogen bonds with the imino groups of bases in pairs remain intact.