We describe a method for distinguishing between minor groove binders and base intercalators that is based on measurements of the fluorescence lifetime of a donor (D) in the presence of an acceptor (A). The D-A pair is separated by a short double helix DNA with which the ligands interact. By plotting the D fluorescence lifetime as a function of the ligand-to-base pair concentration ratio we find a clear signature that distinguishes between the two binding mechanisms: minor groove binding induces an asymptotic decrease of the D fluorescence lifetime, while intercalation gives a monotonically increasing lifetime and the appearance of an additional short lifetime. We assayed Quinacrine, Hoechst and 4′-6′diamidine-2-phenyl indole, which in control experiments performed on oligodeoxyribonucleotides (oligos) lacking the A are demonstrated not to interfere with the D fluorescence. The changes in fluorescence lifetimes measured in the case of dual-labeled oligos are thus caused by structural changes in the DNA that modify the D-A distance. The appearance of the short-lived transient in the fluorescence decay of Ds attached to dual-labeled oligos upon binding of an intercalator can be interpreted as denaturation. © 2007 The Authors.
Nardo, L., Bondani, M., & Andreoni, A. (2008). DNA-ligand binding mode discrimination by characterizing fluorescence resonance energy transfer through lifetime measurements with picosecond resolution. PHOTOCHEMISTRY AND PHOTOBIOLOGY, 84(1), 101-110.
Citazione: | Nardo, L., Bondani, M., & Andreoni, A. (2008). DNA-ligand binding mode discrimination by characterizing fluorescence resonance energy transfer through lifetime measurements with picosecond resolution. PHOTOCHEMISTRY AND PHOTOBIOLOGY, 84(1), 101-110. |
Tipo: | Articolo in rivista - Articolo scientifico |
Carattere della pubblicazione: | Scientifica |
Titolo: | DNA-ligand binding mode discrimination by characterizing fluorescence resonance energy transfer through lifetime measurements with picosecond resolution |
Autori: | Nardo, L; Bondani, M; Andreoni, A |
Autori: | |
Data di pubblicazione: | 2008 |
Lingua: | English |
Rivista: | PHOTOCHEMISTRY AND PHOTOBIOLOGY |
Digital Object Identifier (DOI): | http://dx.doi.org/10.1111/j.1751-1097.2007.00204.x |
Appare nelle tipologie: | 01 - Articolo su rivista |