Please use this identifier to cite or link to this item: http://hdl.handle.net/1822/2587

TitleAzo reductase activity of intact Saccharomyces cerevisiae cells is dependent on the Fre1p component of plasma membrane ferric reductase
Author(s)Ramalho, Patrícia A.
Paiva, Sandra
Paulo, Artur Cavaco
Casal, Margarida
Cardoso, M. Helena
Ramalho, Maria Teresa
KeywordsAzo dyes
Yeasts
Ferric reductase
Plasma membrane redox systems
Issue dateJul-2005
PublisherAmerican Society for Microbiology (ASM)
JournalApplied and Environmental Microbiology
Citation"Applied and environmental microbiology". 71:7 (2005) 3882-3888.
Abstract(s)Unspecific bacterial reduction of azo dyes is a process widely studied in correlation with the biological treatment of coloured wastewaters, but the enzyme system associated with this bacterial capability has never been positively identified. Several ascomycete yeast strains display similar decolourising behaviours. The yeast-mediated process requires an alternative carbon and energy source and is independent of previous exposure to the dyes. When substrate dyes are polar, their reduction is extracellular, strongly suggesting the involvement of an externally directed plasma membrane redox system. The present work demonstrates that, in Saccharomyces cerevisiae, the ferric reductase system participates in the extracellular reduction of azo dyes. The S. cerevisiae deltafre1 and deltafre1deltafre2 mutant strains, but not the deltafre2 strain, showed a much-reduced decolourising capabilities. The FRE1 gene complemented the phenotype of S. cerevisiae deltafre1 cells, restoring the ability to grow without externally added iron and to decolorize the dye, following a pattern similar to the one observed in the wild-type strain. These results suggest that under the conditions tested, Fre1p is a major component of the azo reductase activity.
TypeArticle
URIhttp://hdl.handle.net/1822/2587
DOI10.1128/AEM.71.7.3882-3888.2005
ISSN0099-2240
Peer-Reviewedyes
AccessOpen access
Appears in Collections:CDQuim - Artigos (Papers)

Files in This Item:
File Description SizeFormat 
Article FRE for submission.pdf351,74 kBAdobe PDFView/Open

Partilhe no FacebookPartilhe no TwitterPartilhe no DeliciousPartilhe no LinkedInPartilhe no DiggAdicionar ao Google BookmarksPartilhe no MySpacePartilhe no Orkut
Exporte no formato BibTex mendeley Exporte no formato Endnote Adicione ao seu ORCID