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Inverse Temperature Dependence of Nuclear Quantum Effects in DNA Base Pairs.

ABSTRACT: Despite the inherently quantum mechanical nature of hydrogen bonding, it is unclear how nuclear quantum effects (NQEs) alter the strengths of hydrogen bonds. With this in mind, we use ab initio path integral molecular dynamics to determine the absolute contribution of NQEs to the binding in DNA base pair complexes, arguably the most important hydrogen-bonded systems of all. We find that depending on the temperature, NQEs can either strengthen or weaken the binding within the hydrogen-bonded complexes. As a somewhat counterintuitive consequence, NQEs can have a smaller impact on hydrogen bond strengths at cryogenic temperatures than at room temperature. We rationalize this in terms of a competition of NQEs between low-frequency and high-frequency vibrational modes. Extending this idea, we also propose a simple model to predict the temperature dependence of NQEs on hydrogen bond strengths in general.

SUBMITTER: Fang W

PROVIDER: S-EPMC4933496 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Inverse Temperature Dependence of Nuclear Quantum Effects in DNA Base Pairs.

Fang Wei W Chen Ji J Rossi Mariana M Feng Yexin Y Li Xin-Zheng XZ Michaelides Angelos A

The journal of physical chemistry letters 20160524 11

Despite the inherently quantum mechanical nature of hydrogen bonding, it is unclear how nuclear quantum effects (NQEs) alter the strengths of hydrogen bonds. With this in mind, we use ab initio path integral molecular dynamics to determine the absolute contribution of NQEs to the binding in DNA base pair complexes, arguably the most important hydrogen-bonded systems of all. We find that depending on the temperature, NQEs can either strengthen or weaken the binding within the hydrogen-bonded comp ...[more]

PMID: 27195654

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