ABSTRACT
Site-directed mutagenesis studies in BCPs during the last decade have been funda mental to our understanding the way in which the coordination chemistry of these metal sites affects their electronic structure, redox potentials, and electron transfer properties [100]. Most of the mutagenesis studies have been performed in azurin due to the success in obtaining high-yield expression levels of this protein in E. coli. Although mutations in the copper site alter its spectroscopic features, the protein tolerates such mutations and retains its overall structure.