DNA base pairs: the effect of the aromatic ring on the strength of the Watson-Crick hydrogen bonding.

ABSTRACT: The aromatic ring in DNA bases affects the Watson-Crick binding strength. Our quantum-chemical analyses, which compare the hydrogen bonding between the DNA bases and unsaturated analogs lacking the aromatic ring, reveal that this arises not from π-resonance assistance but from the electron-withdrawing (purines) or electron-donating (pyrimidines) effect of the heteroatom-containing ring on the frontier atoms. This electron redistribution modulates the electrostatics, steric Pauli repulsion, and σ-orbital interactions upon hydrogen bonding.

SUBMITTER: Nieuwland C 

PROVIDER: S-EPMC12314737 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature