Modification of Spectroscopic Properties and Catalytic Activity of <i>Escherichia coli</i> CueO by Mutations of Methionine 510, the Axial Ligand to the Type I Cu

Abstract

Abstract Replacement of Met510, the axial ligand to the type I Cu in a cuprous oxidase CueO, with Leu afforded the three-coordinated type I Cu, while Gln, Ala, and Thr mutations led to the replacement of the thioether ligand with oxygen ligands (amide carbonyl group and water), and characteristic properties of absorption, circular dichroism, and electron paramagnetic resonance spectra of a variety of Met510 mutants were correlated with the changes in redox potential and enzyme activities.