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Interaction of hemin with quadruplex DNA.

ABSTRACT: A DNA enzyme with peroxidase activity is a G-quadruplex-based DNAzyme formed by hemin and G-quadruplex DNA. Activity of peroxide DNAzymes can be influenced by the structure of quadruplex DNA. In this investigation, the interaction of hemin with T30695 G-quadruplex DNA is evaluated. Molecular dynamic simulation indicates that the binding mode of hemin to G-quadruplex DNA is end-stacking, which is consistent with absorption spectroscopy. Based on fluorescence spectroscopy, hemin ejects thiazole orange from bases of four-strand DNA. Circular dichroism spectra showed that no alteration occurs in this type of DNA structure. Graphical Abstract Peroxidase DNAzyme is formed by hemin and G-quadruplex DNA.

SUBMITTER: Ghahremani Nasab M

PROVIDER: S-EPMC5323342 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Interaction of hemin with quadruplex DNA.

Ghahremani Nasab Maryam M Hassani Leila L Mohammadi Nejad Sara S Norouzi Davood D

Journal of biological physics 20161017 1

A DNA enzyme with peroxidase activity is a G-quadruplex-based DNAzyme formed by hemin and G-quadruplex DNA. Activity of peroxide DNAzymes can be influenced by the structure of quadruplex DNA. In this investigation, the interaction of hemin with T30695 G-quadruplex DNA is evaluated. Molecular dynamic simulation indicates that the binding mode of hemin to G-quadruplex DNA is end-stacking, which is consistent with absorption spectroscopy. Based on fluorescence spectroscopy, hemin ejects thiazole or ...[more]

PMID: 27752804

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