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Denaturation of dsDNA Induced by Specific Major Groove Binding of Cadmium Ion to Thymine.

ABSTRACT: The toxicity of cadmium causes varying degrees of risk to organisms. The underlying mechanism has been conventionally attributed to Cd2+-ion-induced oxidative stress. Here, we propose that the Cd2+ ion directly and stably binds with the thymine specifically in the major groove and causes denaturation of dsDNA. Using molecular dynamics simulations, it was found that the Cd2+ ion preferred to bind to the thymine exposed in the major groove. This then destroyed the hydrogen bonds between adenine and thymine, resulting in a mismatched structure of dsDNA. Our findings are expected to promote the understanding of cadmium-induced direct destruction of genomic stability and may also be helpful for the facilitation of the experimental detection of the binding sites.

SUBMITTER: Gao H

PROVIDER: S-EPMC6044676 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Denaturation of dsDNA Induced by Specific Major Groove Binding of Cadmium Ion to Thymine.

Gao Haiyang H Zhu Zhi Z Jiang Xiankai X Guo Jun J Song Bo B Zhang Feng F

ACS omega 20171101 11

The toxicity of cadmium causes varying degrees of risk to organisms. The underlying mechanism has been conventionally attributed to Cd2+-ion-induced oxidative stress. Here, we propose that the Cd2+ ion directly and stably binds with the thymine specifically in the major groove and causes denaturation of dsDNA. Using molecular dynamics simulations, it was found that the Cd2+ ion preferred to bind to the thymine exposed in the major groove. This then destroyed the ...[more]

PMID: 30023584

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