A novel copper-binding protein with characteristics of a metallothionein from a clinical isolate of Candida albicans
Autor: | Takahide Watanabe, Hideaki Matsuoka, Ki-Bong Oh |
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Rok vydání: | 1999 |
Předmět: |
Molecular Sequence Data
Biology Microbiology Candida albicans Metalloprotein Humans Metallothionein Amino Acid Sequence chemistry.chemical_classification Molecular mass Binding protein Candidiasis biology.organism_classification Molecular biology Corpus albicans Biochemistry chemistry biology.protein Electrophoresis Polyacrylamide Gel Protein G Apoproteins Carrier Proteins Copper Cysteine |
Zdroj: | Microbiology. 145:2423-2429 |
ISSN: | 1465-2080 1350-0872 |
DOI: | 10.1099/00221287-145-9-2423 |
Popis: | It is known that clinical isolates of Candida albicans exhibit a high level of resistance to copper salts, although the molecular basis of this resistance is not clear. To investigate this, a novel copper-binding protein was purified from a clinical isolate of C. albicans. The protein was extracted from yeast cells after an induction period of 10 h in a copper-containing suspension medium. It was further purified by size-exclusion chromatography, ultrafiltration and reverse-phase HPLC. All protein fractions were analysed for their protein and copper contents. The copper/protein ratio increased steadily throughout the purification process; the most highly purified fraction showed a 210-fold increase compared to the whole-cell extract, with a recovery of 0.03%. The molecular mass of the protein was 10,000 Da and a reconstitution study using the purified apoprotein suggested that the equivalent extent of Cu(I) binding was approximately 14 mol eq. The amino-terminal segment of the copper-binding protein revealed three Cys-Xaa-Cys motifs, which is typical of a metallothionein (MT), and showed significant homology with mammalian MTs with respect to the positions of the cysteine residues. This is the first report of the isolation of a copper-binding protein from C. albicans. |
Databáze: | OpenAIRE |
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