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arXiv · 1803.07958

Sub-picosecond proton tunnelling in deformed DNA hydrogen bonds under an asymmetric double-oscillator model

Jingxi Luo
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Abstract

We present a model of proton tunnelling across DNA hydrogen bonds, compute the characteristic tunnelling time (CTT) from donor to acceptor and discuss its biological implications. The model is a double oscillator characterised by three geometry parameters describing planar deformations of the H bond, and a symmetry parameter representing the energy ratio between ground states in the individual oscillators. If the symmetry parameter takes its maximum value of 1, then we recover a known model which produced CTTs too large to be biologically relevant; but this is reduced by up to 40 orders of magnitude as the symmetry parameter is decreased. We discover that unless the symmetry parameter is close to 1 or 0, the proton's CTT under any planar deformation is guaranteed to be below one picosecond, which is a biologically relevant time-scale. This supports theories of links between proton tunnelling and biological processes such as spontaneous mutation.

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Jingxi Luo. 2018-03-21. Sub-picosecond proton tunnelling in deformed DNA hydrogen bonds under an asymmetric double-oscillator model. https://doi.org/10.1140/epje%2Fi2018-11690-y

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