[Ru(bpy)2(dppz)](2+) (bpy = 2,2'-bipyridine, dppz = dipyrido- [3,2-a:2',3'-c]phenazine) (RuBD), a long-lifetime metalligand complex, displays favorable photophysical properties. These include long lifetime, polarized emission, but no significant fluorescence from the complex that is not bound to DNA. To show the usefulness of this luminophore (RuBD) for probing the bending and torsional dynamics of nucleic acids, its intensity and anisotropy decays when intercalated into supercoiled and relaxed pTZ18U plasmids were examined using frequency-domain fluorometry with a blue light-emitting diode (LED) as the modulated light source.
View Article and Find Full Text PDFWe have studied the binding of hemoglobin to the red cell membrane by centrifugation and fluorescence methods. The intact red cell was labeled with eosin-5-maleimide (EM), which specifically reacts with lysine 430 of band 3. Even though this residue is not part of the cytoplasmic domain of band 3 (cdb3) associated with hemoglobin binding, fluorescence quenching was observed when hemoglobin bound to inside-out vesicles (IOVs).
View Article and Find Full Text PDFThe metal-ligand complex, [Ru(bpy)2(dppz)]2+ (bpy = 2,2'-bipyridine, dppz = dipyrido[3,2-a:2',3'-c]phenazine) (Ru-BD), was used as a spectroscopic probe for studying nucleic acid dynamics. The Ru-BD complex displays a long lifetime of over 100 ns and a molecular light switch property upon DNA binding due to shielding of its dppz ligand from water. To further show the usefulness of this luminophore (Ru-BD) for probing DNA dynamics, we examined its intensity and anisotropy decays when intercalated into supercoiled and linear pTZ18U plasmids using frequency-domain fluorometry with a light-emitting diode (LED) as the modulated light source.
View Article and Find Full Text PDFThe structural properties and the conformational dynamics of antarctic fish Notothenia coriiceps and mouse metallothioneins were studied by Fourier-transform infrared and fluorescence spectroscopy. Infrared data revealed that the secondary structure of the two metallothioneins is similar to that of other metallothioneins, most of which lack periodical secondary structure elements such as alpha-helices and beta-sheets. However, the infrared spectra of the N.
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