Publication – Schwalbe, Heckel, Wachtveitl

Photoresponsive Formation of an Intermolecular Minimal G-Quadruplex Motif.

Thevarpadam J, Bessi I, Binas O, Gonçalves DP, Slavov C, Jonker HR, Richter C, Wachtveitl J, Schwalbe H, Heckel A. Angew Chem Int Ed Engl. 2016 Feb 18. Abstract or full publication here.

The ability of three different bifunctional azobenzene linkers to enable the photoreversible formation of a defined intermolecular two-tetrad G-quadruplex upon UV/Vis irradiation was investigated. Circular dichroism and NMR spectroscopic data showed the formation of G-quadruplexes with K+ ions at room temperature in all three cases with the corresponding azobenzene linker in an E conformation. However, only the parapara-substituted azobenzene derivative enables photoswitching between a nonpolymorphic, stacked, tetramolecular G-quadruplex and an unstructured state after EZ isomerization.