Metal-specific synthesis of two metallothioneins and gamma-glutamyl peptides in Candida glabrata.
AUTOR(ES)
Mehra, R K
RESUMO
Cellular resistance to heavy metal cytotoxicity in most species is mediated by the binding of metal ions either to a cysteine-rich polypeptide in the metallothionein family or to short cysteine-containing gamma-glutamyl peptides. One of these metal binding systems has been found in most organisms studied. However, the yeast Candida (Torulopsis) glabrata expresses both metallothionein and the gamma-glutamyl peptides for metal detoxification, and each system is regulated in a metal-specific manner. Exposure of C. glabrata to copper salts stimulates formation of two metallothionein-like polypeptides with a cysteine content of 30 mol% and the repeated sequence Cys-Xaa-Cys. The cells synthesize gamma-glutamyl peptides upon exposure to cadmium salts. Penta- and tetrapeptides that form a cadmium-thiolate cluster in a peptide oligomer containing labile sulfur are synthesized.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=282597Documentos Relacionados
- Transport of gamma-glutamyl amino acids: role of glutathione and gamma-glutamyl transpeptidase.
- Inhibition of gamma-glutamyl transpeptidase and induction of glutathionuria by gamma-glutamyl amino acids.
- Involvement of gamma-glutamyl peptides in osmoadaptation of Escherichia coli.
- Identification of a human gamma-glutamyl cleaving enzyme related to, but distinct from, gamma-glutamyl transpeptidase.
- Affinity labeling of gamma-glutamyl transpeptidase and location of the gamma-glutamyl binding site on the light subunit.
