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3,3'-diethylthiatricarbocyanine iodide: a highly sensitive chiroptical reporter of DNA helicity and sequence.

ABSTRACT: Using UV-vis absorption and circular dichroism (CD) spectroscopies, we explored the binding interactions of 3,3'-diethylthiatricarbocyanine iodide (Cy7) with polynucleotides of different sequences and helicity. CD showed to be a very diagnostic tool giving different spectroscopic chiroptical signatures for all explored DNA sequences upon Cy7 binding. Cy7 was able to spectroscopically discriminate between the right handed B-DNA of poly(dG-dC)(2) and its left handed Z-DNA counterpart induced by spermine or Co(III)hexamine via nearly opposite induced circular dichroic signal.

SUBMITTER: Choi JK

PROVIDER: S-EPMC3233455 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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3,3'-diethylthiatricarbocyanine iodide: a highly sensitive chiroptical reporter of DNA helicity and sequence.

Choi Jung Kyu JK D'Urso Alessandro A Trauernicht Mitch M Shabbir-Hussain Murtaza M Holmes Andrea E AE Balaz Milan M

International journal of molecular sciences 20111116 11

Using UV-vis absorption and circular dichroism (CD) spectroscopies, we explored the binding interactions of 3,3'-diethylthiatricarbocyanine iodide (Cy7) with polynucleotides of different sequences and helicity. CD showed to be a very diagnostic tool giving different spectroscopic chiroptical signatures for all explored DNA sequences upon Cy7 binding. Cy7 was able to spectroscopically discriminate between the right handed B-DNA of poly(dG-dC)(2) and its left handed Z-DNA counterpart induced by sp ...[more]

PMID: 22174649

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