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Structures of 2-acetylaminofluorene modified DNA revisited: insight into conformational heterogeneity.

ABSTRACT: Despite the extensive data on dG-AAF, the major DNA adduct derived from the model carcinogen 2-acetylaminofluorene, little is known with respect to its solution structures. Here, we provide NMR/CD evidence for three conformers of dG-AAF in duplex DNA: major groove B-type (B), base-displaced stacked (S), and minor groove wedge (W). The S/B/W-conformational heterogeneities were found to be sensitive to the nature of the flanking DNA sequence contexts and pH.

SUBMITTER: Patnaik S

PROVIDER: S-EPMC2981646 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Structures of 2-acetylaminofluorene modified DNA revisited: insight into conformational heterogeneity.

Patnaik Satyakam S Cho Bongsup P BP

Chemical research in toxicology 20101018 11

Despite the extensive data on dG-AAF, the major DNA adduct derived from the model carcinogen 2-acetylaminofluorene, little is known with respect to its solution structures. Here, we provide NMR/CD evidence for three conformers of dG-AAF in duplex DNA: major groove B-type (B), base-displaced stacked (S), and minor groove wedge (W). The S/B/W-conformational heterogeneities were found to be sensitive to the nature of the flanking DNA sequence contexts and pH. ...[more]

PMID: 20954689

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