... at 23 °C, and the protein concentration waskept constant at 6 lM. The excitation and emissionbandwidths were 5 and 3 nm, respectively. The excitationwavelength was set at 286 nm, and the spectra ... fromAzotobacter vinelandii were studied by fluorescence and NMR spectroscopy. The catalytic Cys230 residue of theenzyme was selectively labelled using [15N]Cys, and changesin1Hand15N NMR resonances ... Azotobacter vinelandiirhodaneseSelenium loading and ion interaction studiesSonia Melino1, Daniel O. Cicero1,2, Maria Orsale1, Fabio Forlani3, Silvia Pagani3 and Maurizio Paci1,21Dipartimento...