title: Magnesium ions in yeast: setting free the metabolism from glucose catabolite repression.
abstract: In a recent work we showed that magnesium (MgII) plays an important role in industrial ethanol production, overcoming the negative effect of the excess of minerals, particularly copper, present in sugarcane juice, with a consequent increase in ethanol yield. This cation has been reported to be involved in several steps of yeast metabolism, acting mainly as a co-factor of several enzymes of fermentation metabolism and protecting yeast cells from stressful conditions. However, despite many physiological investigations, its effect in the molecular mechanisms that control such metabolic activities remains unclear and to date no information concerning its influence on gene expression has been provided. The present work took advantage of the DNA microarray technology to analyse the global gene expression in yeast cells upon fermentation in MgII-supplemented medium. The results of the fermentation parameters confirmed the previous report on the increase in ethanol yield by MgII. Moreover, the gene expression data revealed an unexpected set of up-regulated genes currently assigned as being negatively-regulated by glucose, which belong to respiratory and energy metabolism, the stress response and the glyoxalate cycle. On the other hand, genes involved in ribosome biogenesis were down-regulated. Computational analysis provided evidence for a regulatory network commanded by key transcriptional factors that may be responsible for the biological action of MgIIin yeast cells. In this scenario, MgIIseems to act by reprogramming the yeast metabolism by releasing many genes from glucose catabolite repression with positive consequences for ethanol production and maintenance of cell viability.
authors.affiliation: Interdepartmental Research Group in Metabolic Engineering, Federal University of Pernambuco, Avenida Moraes Rego, No. 1235, Recife, PE 50760-901, Brazil.
authors.forename: Rafael
authors.initials: R
authors.lastname: Barros de Souza
authors.affiliation: Interdepartmental Research Group in Metabolic Engineering, Federal University of Pernambuco, Avenida Moraes Rego, No. 1235, Recife, PE 50760-901, Brazil.
authors.forename: Rayssa Karla
authors.initials: RK
authors.lastname: Silva
authors.affiliation: Interdepartmental Research Group in Metabolic Engineering, Federal University of Pernambuco, Avenida Moraes Rego, No. 1235, Recife, PE 50760-901, Brazil.
authors.forename: Dayvison Soares
authors.initials: DS
authors.lastname: Ferreira
authors.affiliation: Laboratory of Bioinformatics and Evolutionary Biology, Federal Rural University Pernambuco. Rua Dom Manoel de Medeiros, s/n, Recife, PE 52171-900, Brazil.
authors.forename: Sérgio
authors.initials: S
authors.lastname: de Sá Leitão Paiva Junior
authors.affiliation: Interdepartmental Research Group in Metabolic Engineering, Federal University of Pernambuco, Avenida Moraes Rego, No. 1235, Recife, PE 50760-901, Brazil and Department of Antibiotics, Federal University of Pernambuco. Avenida Moraes Rego, No. 1235, Recife, PE 50760-901, Brazil.
authors.forename: Will
authors.initials: W
authors.lastname: de Barros Pita
authors.affiliation: Interdepartmental Research Group in Metabolic Engineering, Federal University of Pernambuco, Avenida Moraes Rego, No. 1235, Recife, PE 50760-901, Brazil and Department of Genetic and Federal University of Pernambuco. Avenida Moraes Rego, No. 1235, Recife, PE 50760-901, Brazil.
authors.forename: Marcos Antonio
authors.initials: MA
authors.lastname: de Morais Junior
mesh_terms: D057465:Catabolite Repression / Q000187:drug effects*; D004734:Energy Metabolism / Q000187:drug effects; D000431:Ethanol / Q000378:metabolism; D005285:Fermentation / Q000187:drug effects; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects*; D053263:Gene Regulatory Networks; D005947:Glucose / Q000737:chemistry / Q000378:metabolism*; D008274:Magnesium / Q000494:pharmacology*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D059467:Transcriptome
chemical_list: D029701:Saccharomyces cerevisiae Proteins; D000431:Ethanol; D008274:Magnesium; D005947:Glucose