Structure Determination of an Ag(I) -Mediated Cytosine-Cytosine Base Pair within DNA Duplex in Solution with (1) H/(15) N/(109) Ag NMR Spectroscopy.
Related Articles Structure Determination of an Ag(I) -Mediated Cytosine-Cytosine Base Pair within DNA Duplex in Solution with (1) H/(15) N/(109) Ag NMR Spectroscopy.
Chemistry. 2016 Aug 9;
Authors: Dairaku T, Furuita K, Sato H, Šebera J, Nakashima K, Kondo J, Yamanaka D, Kondo Y, Okamoto I, Ono A, Sychrovský V, Kojima C, Tanaka Y
Abstract
The structure of an Ag(I) -mediated cytosine-cytosine base pair, C-Ag(I) -C, was determined with NMR spectroscopy in solution. The observation of 1-bond (15) N-(109) Ag J-coupling ((1) J((15) N,(109) Ag): 83 and 84 Hz) recorded within the C-Ag(I) -C base pair evidenced the N3-Ag(I) -N3 linkage in C-Ag(I) -C. The triplet resonances of the N4 atoms in C-Ag(I) -C demonstrated that each exocyclic N4 atom exists as an amino group (-NH2 ), and any isomerization and/or N4-Ag(I) bonding can be excluded. The 3D structure of Ag(I) -DNA complex determined with NOEs was classified as a B-form conformation with a notable propeller twist of C-Ag(I) -C (-18.3±3.0°). The (109) Ag NMR chemical shift of C-Ag(I) -C was recorded for cytidine/Ag(I) complex (?((109) Ag): 442 ppm) to completed full NMR characterization of the metal linkage. The structural interpretation of NMR data with quantum mechanical calculations corroborated the structure of the C-Ag(I) -C base pair.
PMID: 27505707 [PubMed - as supplied by publisher]
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