title: Modifications of laccase activities of copper efflux oxidase, CueO by synergistic mutations in the first and second coordination spheres of the type I copper center.
abstract: The redox potential of type I copper in the Escherichia coli multicopper oxidase CueO was shifted in the positive or negative direction as a result of the single, double, and triple mutations in the first and second coordination spheres: the formation of the NH···S(-)(Cys500 ligand) hydrogen bond, the breakdown of the NH(His443 ligand)···O(-)(Asp439) hydrogen bond, and the substitution of the Met510 ligand for the non-coordinating Leu or coordinating Gln. Laccase activities of CueO were maximally enhanced 140-fold by virtue of the synergistic effect of mild mutations at and at around the ligand groups to type I copper.
authors: Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan.
authors: Kunishige
authors: K
authors: Kataoka
authors: Hiroki
authors: H
authors: Kogi
authors: Seiya
authors: S
authors: Tsujimura
authors: Takeshi
authors: T
authors: Sakurai
mesh_terms: D000595:Amino Acid Sequence; D003300:Copper / Q000737:chemistry*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics*; D042845:Laccase / Q000737:chemistry* / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation; D010088:Oxidoreductases / Q000737:chemistry* / Q000235:genetics*
chemical_list: D029968:Escherichia coli Proteins; D003300:Copper; D010088:Oxidoreductases; C499679:cueO protein, E coli; D042845:Laccase