title: X-ray absorption studies of yeast copper metallothionein.
abstract: The local structures of the metal sites in copper metallothionein from Saccharomyces cerevisiae have been investigated by x-ray absorption spectroscopy at the copper and sulfur K edges. Analysis of the EXAFS (extended x-ray absorption fine structure) data indicates that each copper is trigonally coordinated to sulfur at a distance of 2.23 A. Cu-Cu interactions at 2.7 and 3.9 A have also been tentatively identified. Sulfur K edge data are compatible with cysteinyl thiolates bridging each of the eight Cu(I) ions. The data support a model for the copper cluster in yeast metallothionein consisting of a Cu8S12 core. EXAFS data on two specifically engineered carboxyl-terminal truncated mutants reveal that the copper coordination in the mutants is similar to that observed in the wild-type protein.
authors.affiliation: Exxon Research & Engineering Company, Annandale, New Jersey 08801.
authors.forename: G N
authors.initials: GN
authors.lastname: George
authors.forename: J
authors.initials: J
authors.lastname: Byrd
authors.forename: D R
authors.initials: DR
authors.lastname: Winge
mesh_terms: D000465:Algorithms; D002352:Carrier Proteins; D004577:Electron Probe Microanalysis; D008668:Metallothionein; D012441:Saccharomyces cerevisiae / Q000032:analysis*; D014961:X-Ray Diffraction
chemical_list: C500769:CUP1-1 protein, S cerevisiae; D002352:Carrier Proteins; C007121:copper thionein; D008668:Metallothionein