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A metal-mediated base pair that discriminates between the canonical pyrimidine nucleobases.

ABSTRACT: A nucleoside analogue comprising the ligand 1H-imidazo[4,5-f][1,10]phenanthroline (P) was applied to develop a molecular beacon capable of discriminating the canonical nucleobases cytosine and thymine. The beacon is based on the formation of a stable Ag+-mediated base pair between P and cytosine, whereas the presence of Ag+ strongly destabilizes nucleic acids comprising an artificial base pair between P and thymine. Metal-mediated base pair formation was investigated by temperature-dependent UV spectroscopy and CD spectroscopy and complemented by extensive DFT calculations. The molecular beacon significantly extends the application spectrum of nucleic acids with metal-mediated base pairs. It is of potential use in the detection of single-nucleotide polymorphisms.

SUBMITTER: Jash B

PROVIDER: S-EPMC5360170 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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A metal-mediated base pair that discriminates between the canonical pyrimidine nucleobases.

Jash Biswarup B Scharf Philipp P Sandmann Nikolas N Fonseca Guerra Célia C Megger Dominik A DA Müller Jens J

Chemical science 20161012 2

A nucleoside analogue comprising the ligand 1H-imidazo[4,5-f][1,10]phenanthroline (P) was applied to develop a molecular beacon capable of discriminating the canonical nucleobases cytosine and thymine. The beacon is based on the formation of a stable Ag+-mediated base pair between P and cytosine, whereas the presence of Ag+ strongly destabilizes nucleic acids comprising an artificial base pair between P and thymine. Metal-mediated base pai ...[more]

PMID: 28451274

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