Modulation of the Directionality of Hole Transfer between the Base and the Sugar-Phosphate Backbone in DNA with the Number of Sulfur Atoms in the Phosphate Group.

ABSTRACT: This work shows that S atom substitution in phosphate controls the directionality of hole transfer processes between the base and sugar-phosphate backbone in DNA systems. The investigation combines synthesis, electron spin resonance (ESR) studies in supercooled homogeneous solution, pulse radiolysis in aqueous solution at ambient temperature, and density functional theory (DFT) calculations of in-house synthesized model compound dimethylphosphorothioate (DMTP(O^-)═S) and nucleotide (5'-O-methoxyphosphorothioyl-2'-deoxyguanosine (G-P(O^-)═S)). ESR investigations show that DMTP(O^-)═S reacts with Cl₂^•- to form the σ²σ*¹ adduct radical -P-S[Formula: see text]Cl, which subsequently reacts with DMTP(O^-)═

SUBMITTER: Denisov SA 

PROVIDER: S-EPMC8776618 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature