Effects of Intense Electric Fields on the Double Proton Transfer in the Watson-Crick Guanine-Cytosine Base Pair

Document Type

Article

Source of Publication

Journal of Physical Chemistry B

Publication Date

9-20-2018

Abstract

Copyright © 2018 American Chemical Society. The double proton transfer reaction in the guanine-cytosine (GC) base pair is studied, using density functional theory, to understand the chances of mutations under the effect of uniform electric fields in the order of 108 to 109 V m-1. On the basis of potential energy surfaces, reaction Gibbs energies, equilibrium constants, imaginary frequencies, forward and reverse barrier heights, tunneling-corrected rate constants, half-lives of the forward and reverse reactions, percent tautomerization, and Boltzmann distributions, it was found that fields ≥+3.60 × 109 V m-1 facilitate the mutation in the GC base pair and reduce the rectification of point mutations. Fields applied along the double proton transfer in the -x (defined in the C to G direction) direction favor the canonical over the rare tautomers. Tunneling-corrected rate constants of the forward reaction increase exponentially with stronger fields in the -x direction and follow a Gaussian curve for the reverse reaction.

ISSN

1520-5207

Publisher

American Chemical Society

Volume

122

Issue

37

First Page

8631

Last Page

8641

Disciplines

Physical Sciences and Mathematics

Keywords

Boltzmann equation, Density functional theory, Electric fields, Equilibrium constants, Positive ions, Potential energy, Proton transfer, Quantum chemistry, Surface reactions, Boltzmann distribution, Double proton transfer, Forward reactions, Guanine cytosines, Imaginary frequency, Reverse reactions, Tautomerizations, Uniform electric fields, Rate constants, cytosine, DNA, guanine, proton, base pairing, chemical model, chemistry, density functional theory, electricity, genetics, point mutation, thermodynamics, Base Pairing, Cytosine, Density Functional Theory, DNA, Electricity, Guanine, Models, Chemical, Point Mutation, Protons, Thermodynamics

Scopus ID

85053274738

Indexed in Scopus

yes

Open Access

no

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