A contribution for the identification of the azo reductase activity in intact yeast cells

Bibliographic Details
Main Author: Ramalho, Patrícia Alexandra Costa Ferreira
Publication Date: 2004
Other Authors: Paiva, Sandra, Paulo, Artur Cavaco, Casal, Margarida, Ramalho, Maria Teresa, Cardoso, M. Helena
Language: eng
Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
Download full: https://hdl.handle.net/1822/2162
Summary: Poster apresentado no International Congress on Yeasts (ICY) -Yeasts in Science and Biotechnology : The Quest for Sustainable Development", 11, Rio de Janeiro, Brasil, Agosto 2004.
id RCAP_60917b67f52f5b9fb08f13c6272dd611
oai_identifier_str oai:repositorium.sdum.uminho.pt:1822/2162
network_acronym_str RCAP
network_name_str Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
repository_id_str https://opendoar.ac.uk/repository/7160
spelling A contribution for the identification of the azo reductase activity in intact yeast cellsAzo reductaseFRE1YeastsPoster apresentado no International Congress on Yeasts (ICY) -Yeasts in Science and Biotechnology : The Quest for Sustainable Development", 11, Rio de Janeiro, Brasil, Agosto 2004.Azo dyes are synthetic organic colorants which are extensively used in textile, food and cosmetic industries. A large fraction of these dyes is released into the environment even after conventional wastewater treatments. This is a worldwide problem and particularly a problem in regions where textile industries release large quantities of coloured wastewater to water courses. In an attempt to develop a biological treatment for colour removal we isolated several ascomycete yeast strains from contaminated soil based on its capacity to decolourize soluble azo dyes. We studied the process in batch cultures and have demonstrated that the colour loss was due to a reductase activity, expressed constitutively, which could transform azo dyes into colourless amines [1]. In order to understand the process involved in this reduction we selected a Saccharomyces cerevisiae strain (BLC0276) with this capacity. This strain reduced model azo dyes in 8-16 h. We decided to further investigate which enzyme(s) could be involved in this reduction. It was found that in S. cerevisiae there is a membrane redox system with an externally directed reductase – the ferric reductase system, responsible for the extracellular reduction of ferric to ferrous iron previous to uptake, and involving the genes fre1 and fre2. Several know inhibitors of this system were investigated like excess of iron in the medium, CCCP, DPI, chloroquine and p-chloromercurybenzoic acid. Several of these compounds managed to inhibit the decolourizing activity. We also deleted the genes fre1 and fre2 in our strain and analysed the effect on decolourizing activity. Once again the process was retarded in fre1 and fre1fre2 strains. The effect of fre2 deletion was negligible. The deletion of fre1 retarded the decolourizing capability showing the involvement of this system. However the capacity was not completely removed indicating that cells have an alternative reducing system. [1] Ramalho, P.A., Scholze, H., Cardoso, M.H., Ramalho, M.T., Oliveira-Campos, A.M. 2002 Improved conditions for the aerobic reductive decolourization of azo dyes by Candida zeylanoides. Enz Microbiol Technol 31: 848-854.BIOEFTEX Project.Universidade do MinhoRamalho, Patrícia Alexandra Costa FerreiraPaiva, SandraPaulo, Artur CavacoCasal, MargaridaRamalho, Maria TeresaCardoso, M. Helena2004-082004-08-01T00:00:00Zconference posterinfo:eu-repo/semantics/publishedVersionapplication/pdfhttps://hdl.handle.net/1822/2162enginfo:eu-repo/semantics/openAccessreponame:Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)instname:FCCN, serviços digitais da FCT – Fundação para a Ciência e a Tecnologiainstacron:RCAAP2025-03-15T01:17:13Zoai:repositorium.sdum.uminho.pt:1822/2162Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireinfo@rcaap.ptopendoar:https://opendoar.ac.uk/repository/71602025-05-28T16:18:24.092029Repositórios Científicos de Acesso Aberto de Portugal (RCAAP) - FCCN, serviços digitais da FCT – Fundação para a Ciência e a Tecnologiafalse
dc.title.none.fl_str_mv A contribution for the identification of the azo reductase activity in intact yeast cells
title A contribution for the identification of the azo reductase activity in intact yeast cells
spellingShingle A contribution for the identification of the azo reductase activity in intact yeast cells
Ramalho, Patrícia Alexandra Costa Ferreira
Azo reductase
FRE1
Yeasts
title_short A contribution for the identification of the azo reductase activity in intact yeast cells
title_full A contribution for the identification of the azo reductase activity in intact yeast cells
title_fullStr A contribution for the identification of the azo reductase activity in intact yeast cells
title_full_unstemmed A contribution for the identification of the azo reductase activity in intact yeast cells
title_sort A contribution for the identification of the azo reductase activity in intact yeast cells
author Ramalho, Patrícia Alexandra Costa Ferreira
author_facet Ramalho, Patrícia Alexandra Costa Ferreira
Paiva, Sandra
Paulo, Artur Cavaco
Casal, Margarida
Ramalho, Maria Teresa
Cardoso, M. Helena
author_role author
author2 Paiva, Sandra
Paulo, Artur Cavaco
Casal, Margarida
Ramalho, Maria Teresa
Cardoso, M. Helena
author2_role author
author
author
author
author
dc.contributor.none.fl_str_mv Universidade do Minho
dc.contributor.author.fl_str_mv Ramalho, Patrícia Alexandra Costa Ferreira
Paiva, Sandra
Paulo, Artur Cavaco
Casal, Margarida
Ramalho, Maria Teresa
Cardoso, M. Helena
dc.subject.por.fl_str_mv Azo reductase
FRE1
Yeasts
topic Azo reductase
FRE1
Yeasts
description Poster apresentado no International Congress on Yeasts (ICY) -Yeasts in Science and Biotechnology : The Quest for Sustainable Development", 11, Rio de Janeiro, Brasil, Agosto 2004.
publishDate 2004
dc.date.none.fl_str_mv 2004-08
2004-08-01T00:00:00Z
dc.type.driver.fl_str_mv conference poster
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
status_str publishedVersion
dc.identifier.uri.fl_str_mv https://hdl.handle.net/1822/2162
url https://hdl.handle.net/1822/2162
dc.language.iso.fl_str_mv eng
language eng
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.source.none.fl_str_mv reponame:Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
instname:FCCN, serviços digitais da FCT – Fundação para a Ciência e a Tecnologia
instacron:RCAAP
instname_str FCCN, serviços digitais da FCT – Fundação para a Ciência e a Tecnologia
instacron_str RCAAP
institution RCAAP
reponame_str Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
collection Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
repository.name.fl_str_mv Repositórios Científicos de Acesso Aberto de Portugal (RCAAP) - FCCN, serviços digitais da FCT – Fundação para a Ciência e a Tecnologia
repository.mail.fl_str_mv info@rcaap.pt
_version_ 1833595864129470464

Similar Items