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Differential stabilization of adenine quartets by anions and cations.

ABSTRACT: We have investigated the structures and stabilities of four different adenine quartets with alkali and halide ions in the gas phase and in water, using dispersion-corrected density functional theory at the BLYP-D/TZ2P level. First, we examine the empty quartets and how they interact with alkali cations and halide anions with formation of adenine quartet-ion complexes. Second, we examine the interaction in a stack, in which a planar adenine quartet interacts with a cation or anion in the periphery as well as in the center of the quartet. Interestingly, for the latter situation, we find that both cations and anions can stabilize a planar adenine quartet in a stack.

SUBMITTER: van der Wijst T

PROVIDER: S-EPMC2830606 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Differential stabilization of adenine quartets by anions and cations.

van der Wijst Tushar T Lippert Bernhard B Swart Marcel M Guerra Célia Fonseca CF Bickelhaupt F Matthias FM

Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry 20091127 3

We have investigated the structures and stabilities of four different adenine quartets with alkali and halide ions in the gas phase and in water, using dispersion-corrected density functional theory at the BLYP-D/TZ2P level. First, we examine the empty quartets and how they interact with alkali cations and halide anions with formation of adenine quartet-ion complexes. Second, we examine the interaction in a stack, in which a planar adenine quartet interacts with a cation or anion in the peripher ...[more]

PMID: 19943071

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