title: NMR Structure of a Triangulenium-Based Long-Lived Fluorescence Probe Bound to a G-Quadruplex.
abstract: An NMR structural study of the interaction between a small-molecule optical probe (DAOTA-M2) and a G-quadruplex from the promoter region of the c-myc oncogene revealed that they interact at 1:2 binding stoichiometry. NMR-restrained structural calculations show that binding of DAOTA-M2 occurs mainly through π-π stacking between the polyaromatic core of the ligand and guanine residues of the outer G-quartets. Interestingly, the binding affinities of DAOTA-M2 differ by a factor of two for the outer G-quartets of the unimolecular parallel G-quadruplex under study. Unrestrained MD calculations indicate that DAOTA-M2 displays significant dynamic behavior when stacked on a G-quartet plane. These studies provide molecular guidelines for the design of triangulenium derivatives that can be used as optical probes for G-quadruplexes.
authors: Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia.
authors: Anita
authors: A
authors: Kotar
authors: Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia.
authors: Baifan
authors: B
authors: Wang
authors: Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK.
authors: Arun
authors: A
authors: Shivalingam
authors: Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK.
authors: Jorge
authors: J
authors: Gonzalez-Garcia
authors: Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK.
authors: Ramon
authors: R
authors: Vilar
authors: Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia. Janez.plavec@ki.si.|EN-FIST Center of Excellence, Trg OF 13, 1000, Ljubljana, Slovenia. Janez.plavec@ki.si.|Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, Ljubljana, Slovenia. Janez.plavec@ki.si.
authors: Janez
authors: J
authors: Plavec
keywords: G-quadruplexes; NMR spectroscopy; molecular dynamics; optical probes; structure elucidation