Spectroscopic characterization of the copper(I)-thiolate cluster in the DNA-binding domain of yeast ACE1 transcription factor.
A polypeptide containing the amino-terminal region of ACE1 (residues 1-122; 122*), the activator of yeast Cu-metallothionein gene transcription, shows charge-transfer and metal-centered UV absorption bands, and orange luminescence which are characteristic of Cu-cysteinyl thiolate cluster structures. These spectral features are abolished by the Cu(I) complexing agents CN- and diethyldithiocarbamate or exposure to acid, but not by the Cu(II) chelator, EDTA. Binding of the polypeptide to its specific DNA recognition site, but not to calf-thymus double-stranded DNA, induces quenching of its Tyr and Cu-S cluster luminescence emission. The CD spectrum is characteristic of a tightly folded structure that may be organized around the Cu cluster.
Casas-Finet
J R
JR
Department of Chemistry and Biochemistry, Univesity of Maryland Baltimore County 21228.
Hu
S
S
Hamer
D
D
Karpel
R L
RL
D000595:Amino Acid Sequence; D003300:Copper / Q000032:analysis*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005800:Genes, Fungal; D049449:Luminescence; D008668:Metallothionein / Q000235:genetics; D008969:Molecular Sequence Data; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013438:Sulfhydryl Compounds / Q000032:analysis; D014157:Transcription Factors / Q000378:metabolism*
C060256:CUP2 protein, S cerevisiae; D004268:DNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; D013438:Sulfhydryl Compounds; D014157:Transcription Factors; D003300:Copper; D008668:Metallothionein