Lepidopteran insects like Helicoverpa armigera, more commonly known as the cotton bollworm, are economically important pests of a wide variety of crops throughout the world. The Helicoverpa armigera stunt virus (HaSV), a tetravirus with a bipartite single-stranded positive-sense RNA genome, has great potential as a biological pesticide against H. armigera. The larger genomic strand of this virus (RNA1) encodes the viral replicase, while the other (RNA2) encodes the 71 kDa capsid protein precursor (p71). 240 copies of p71 assemble into a procapsid with the concomitant encapsidation of the viral RNA. This is followed by a complex maturation event that is characterized by the autoproteolytic cleavage of p71 into the 64 kDa capsid protein (P64) and a 7 kDa peptide (p7). The rearrangements that occur during maturation results in the formation of mature HaSV capsids that can thereupon deliver RNA to other susceptible host cells. The principal objective of the research described in this study was to demonstrate that this virus could be assembled in Saccharomyces cerevisiae. S. cerevisiae expression vectors were constructed for the production of p71. This protein was detected in cell lysates from two different strains of S. cerevisiae, both containing either chromosomal or episomal copies of an expression cassette for P71. A number of factors relating to the expression of P71 (e.g. strains used, expression loci and expression rate) and the preparation of protein extracts from S. cerevisiae (e.g. the presence of various protease inhibitors and salt concentrations) were examined to attain optimal levels of soluble p71. A small fraction of the optimized soluble p71 was shown to be in the form of virus-like particles (VLPs), with a yield of ≤10⁷ VLPs from a 1.5l culture of P71⁺ cells. These particles were exclusively in the procapsid form, had a similar buoyant density to that of wild-type HaSV and could undergo maturation when the pH was reduced to 5. S. cerevisiae vectors were constructed for the episomal expression of the HaSV genomic RNAs. These vectors directed the transcription of RNA1 and RNA2 transcripts, which had similar sizes to those of the HaSV genomic RNAs. Mature HaSV particles were purified from cells, transgenic for P71, RNA1 and RNA2, by way of two different virus purification protocols that were developed during this study. RT-PCR analyses on RNA-extracts from these particles demonstrated that RNA transcripts, which were produced in trans with p71, could be encapsidated by HaSV capsids in S. cerevisiae. A droplet-feed bioassay on H. armigera larvae demonstrated that the S. cerevisiae-derived HaSV particles caused impaired larval development. This response was correlated with the detection of HaSV RNA2 in RNA extractions from larvae that were used in this bioassay. The results that were generated through the course of this study, provided proof for the concept of the non-host production of infectious HaSV particles from S. cerevisiae. This work could serve as a foundation for future research on the development of an expression system for the large-scale production of this virus as a biopesticide.

Uga3p, a member of the zinc binuclear cluster transcription factor family, is required for [gamma]-aminobutyric acid-dependent transcription of the UGA genes in Saccharomyces cerevisiae. Crystallographic data of some of the protein-DNA complexes of this family reveal that members of this family bind to CGG triplets. A conserved 19-nucleotide activation element in certain UGA gene promoter regions contains a CCG-N4-CGG everted repeat, proposed to be the binding site of Uga3p, UAS[subscript GABA]. The spacer region (N4) between the CGG triplets has been suggested to be the specificity determinant for binding to UAS[subscript GABA]. The data available from the Saccharomyces genome database indicates that there are multiple repeats of -CCG-N4-CGG- regions within the genome. These transcription factors are involved in the activation of specific pathways and the question arises as to how their specificity of binding is determined. The aim of this study was to understand the binding characteristics of Uga3p to UAS[subscript GABA] and to determine the affinity and specificity of this interaction. In this study, full-length (tagged and untagged) and truncated (1-124 a.a.) Uga3p was produced in a heterologous expression system (E. coli). The interaction of Uga3p with UAS[subscript GABA] in Saccharomyces cerevisiae was characterized in terms of binding in vitro and the transcriptional activation of lacZ reporter genes in vivo. The Uga3p was capable of binding to these sites in vitro independent of exogenous GABA. Electrophoretic mobility shift assays (EMSA) of the full-length Uga3p with the wild type UAS[subscript GABA] sequences produced two distinct mobility complexes. The complexes formed in the EMSA of the full-length Uga3p were those specific to the interaction of the Uga3p to UAS[subscript GABA]. The truncated Uga3p(1-124 a.a.), which has the DNA-binding zinc cluster domain, the linker region and the putative coiled-coil domain was not functionally equivalent to the full-length protein with respect to binding in vitro because the EMSAs of the UAS[subscript GABA] with the truncated Uga3p produced indistinct complexes. EMSAs using mutant UAS[subscript GABA] sequences and heterologously-produced full-length Uga3p, demonstrated that UAS[subscript GABA] consists of two, independent Uga3p-binding sites. This work presents evidence that the two Uga3p molecules bound to UAS[subscript GABA] most likely interact with each other. Unlike other zinc cluster binding sites the Uga3p-binding site is an asymmetric site of 5’-SGCGGNWWT-3’ (S= G or C, W = A or T and N = no nucleotide or G or C). UAS[subscript GABA] is a palindrome containing the two asymmetric Uga3p-binding sites. The two-site consensus sequence required for the binding of Uga3p to the UAS[subscript GABA] is present upstream of UGA1 (region -387 to -370) and UGA4 (region -403 to -387). Furthermore, a single Uga3p-binding site was identified in the 5’ untranslated regions of UGA2 (region -219 to -211). GABA-dependent transcriptional activation by UAS[subscript GABA] in vivo could be directly correlated to a high affinity, specific interaction of two Uga3p molecules to this UAS. Binding with high affinity required the conserved sequences flanking the everted repeat. This study provided evidence that the binding pattern of Uga3p is novel compared to other zinc cluster motifs investigated, as the sequences flanking the everted repeat are important regions for recognition by Uga3p. The studies with the truncated Uga3p (1 –124 a.a.), also suggested that the regions C-terminal to the DNA-binding motif and putative coiled-coil area of this protein are important for Uga3p-specific interactions with UAS[subscript GABA]. Investigation of regions C-terminal to the zinc cluster, linker and putative coiledcoil revealed an eight-motif regulatory region similar to that in other zinc cluster proteins. This indicated that the regions C-terminal to these domains are important for the regulation and activity of these proteins. A putative seven repeat WD40-like motif was identified within this region. This putative domain has been speculated to be important for protein-protein interactions. Phosphorylation and dephosphorylation in other proteins of this class have been indicated to be important for the regulation of the activity of these proteins. The bioinformatic analysis of Uga3p revealed two possible cAMP/cGMP-dependent protein kinase phosphorylation sites, four putative protein kinase C phosphorylation motifs and four putative casein kinase II phosphorylation motifs. This study has contributed to the understanding of the nature of interactions between Uga3p and its specific UAS [subscript GABA] and how the regions flanking the everted repeat determine its specificity. The comparison of the nature of the binding of truncated and full-length Uga3p in vitro provided evidence for the role played by the full-length protein in determining this specific interaction. This evidence suggested that the in vitro binding evidence for other proteins of this family, using truncated peptides that carry the DNA-binding domain, might not reflect the true nature of interactions between the proteins of this class and their specific UASs in vivo.

Orientador: Ranulfo Monte Alegre / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-07-20T12:00:34Z (GMT). No. of bitstreams: 1 Bittar_MariaAssima_M.pdf: 2629105 bytes, checksum: 1241efa399ee2645ddb9efa0313bfb4d (MD5) Previous issue date: 1995 / Resumo: Saccharomyces lipolytica CCT 0913 foi utilizada em meio de cultura contendo emulsão de óleo solúvel de corte usada como única fonte de carbono, para produção de proteína microbiana (SCP) e redução de Demanda Química de Oxigênio. Foram utilizados dois meios de cultura, um deles contendo (NH4)2SO4 cuja concentração variou de 2,5 a 15 g/l e o outro NH4Cl, cuja concentração variou de 0,1 a 1,5 g/l. No meio contendo (NH4)2SO4 verificou-se a influência do pH inicial (5,0, 5,5 e 6,5) no crescimento celular em erlenmeyers. O melhor resultado, 1,12 g/l de massa celular seca com 31,92% de proteína foi obtido com 15 g/l de (NH4)2SO4, pH 5,5 e 5% de emulsão de óleo solúvel de corte. No meio contendo NH4Cl, as fermentações foram conduzidas em erlenmeyers e fermentadores de 1 e 6 litros. Em fermentador de 6 litros, a porcentagem de emulsão de óleo solúvel de corte variou de 5 a 40% (v/v) no meio de cultura. Com 20% de emulsão de óleo solúvel de corte e 1,0 g/l de NH4Cl foi possível produzir 3,19 g/l de massa celular seca e reduzir a DQO do meio de cultura de 6188 para 4596 mg/l. / Abstract: A medium containing used cutting oil emulsion as carbon source was used by Saccharomyces lipolytica CCT 0913 for microbial protein production (SCP) and Chemical Oxygen Demand (COD) removal. It was utilized two culture medium, one of them containing (NH4)2SO4 its concentration was studied in the range of 2.5 to 15 g/1. In the other, containing NH4Cl, concentration was changed in the range of 0.1 to 1.5 g/1. In the medium containing (NH4)2SO4 it was verified the initial pH influence (5.0, 5.5 e 6.5) in cellular growth in erlenmeyers flasks. The best result (1.12 g/1 of cellular dried mass with 31.92% of protein) was obtained with 15 g/1 of (NH4)2SO4, initial pH 5.5 and 5% of cutting oil emulsion. With medium containing NH4Cl the fermentations were carried out in erlenmeyers and fermentors of 1 and 6 liters. In the 6 liter fermentor the percentage of cutting oil emulsion was changed in the range of 5 to 40% (v/v) in the culture medium. With 20% of cutting oil emulsion and 1.0 g/1 of NH4Cl it was possible to produce 3.19 g/1 of cellular dried mass and to reduce the medium COD from 6188 to 4596 mg/1. / Mestrado / Mestre em Engenharia de Alimentos

Orientador : Vanderlei Perez Canhos / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-07-16T16:55:40Z (GMT). No. of bitstreams: 1 Kaji_DeniseAkiko_M.pdf: 3626927 bytes, checksum: f425ac34cd6d2ee6fd67051dd80c4baf (MD5) Previous issue date: 1989 / Resumo: O trabalha enfoca a influência da temperatura e o efeito da infecção lática sobre 3 produção de álcool e a viabilidade de duas linhagens de Saccharoswces cerevisiae (NRRL Y-2342 e FTPT 0472) cultivadas em caldo de cana enriquecido com N e P, a pH 4,5, e incubadas em um gradiente de temperatura na faixa entre 28 e 40 ºC. Determinações da concentração de leveduras (plaqueamento e microscopia), bactérias (plaqueamento), CO2 (gravimetria), massa celular seca (gravimetria), pH (potenciometria), açúcar (colorimetria) e etanol (cromatografia gasosa) foras quantificadas no substrato inicial e no fermentado. A partir desses dados, verificou-se que as temperaturas ótimas para a produção de etanol foram 38 ºC para a linhagem de NRRL Y-2342 e 34ºC para a linhagem FTPT 0472. 0 valor do coeficiente de rendimento alcoólico máximo apresentou o mesmo valor para ambas as linhagens (Yp/s = 0,47) e uma produtividade global ligeiramente maior para a linhagem NRRL Y-2342 (l1%). A reprodução das leveduras foi prejudicada a 40°C e beneficiada a temperaturas mais baixas que as indicadas para a produção máxima de etanol. A presença de Leaconostoc ou Lactobacillus no inicio das fermentações ocasionou respectivamente, a redução (5 %) ou aumento (6%) do rendimento alcoólico quando comparadas às fermentações realizadas cora culturas puras de S. cerevisiae. As produtividades obtidas com as culturas contaminadas foram superiores, exceto em algumas fermentações contaminadas com Lactobacillus. Ambos os contaminantes afetaram adversamente o brotamento da 1inhagem NRRL Y-2342 e pouco influíram no brotamento da linhagem FTPT 0472. No final das fermentações, o Leaconostoc não pode ser detectado enquanto que o nível de Lactobacillus se manteve praticamente constante. A ausência do Leaconostoc no final das fermentações pode ser atribuída à característica de crescimento do Leaconostoc e ao etanol produzido pelas leveduras, no meio utilizado / Abstract: The goal of this work is to study the influence of temperature and infection of lactic acid bacteria on alcoholic yield and viability of two strains of two Saccharomyces cerevisiae (NRRL and FTPT 0472) growing on cane sugar broth at pH 4,5 supplemented with N and P. The incubation was carried on a temperature gradient incubator between 28 and 40ºC. Determination of yeast concentration (plate count and microscopy), bacterial concentration (plate county CO2 (gravimetry), dry cell mass (gravimetry), pH (potenciometry), sugar concentration (colorimetry) and ethanol (gas chromatography) was done in the initial and final samples. The optimum temperature for ethanol product ion was found to be 38 °C for strain NRRL Y-2342 and 34 ºC for strain FTPT 0472. The maximum alcoholic yield coefficient obtained was the- same for bath strains (Yp/s = 0,47). However the productivity was slightly higher (11%) for the strain NRRL Y-2342. The reproduction of yeasts was adversely affected above 40ºC but was enhanced at 1ower temperatures (28 to 32 °C) .There was a decrease in the alcoholic, yield of 5% in the presence of Leaconostoc and an increase of 6% in the presence of Lactobacillus. The productivity obtained with contaminated cultures was higher, with the exception of some experiments contaminated with Lactobacillus. Both bacterial contaminants affected adversely the budding of strain NRRL Y-2342 but did not affect the budding of strain FTPT 0472. At the end of fermentation the level of the Lactobacillus contamination remained constant, whereas viable cells of Leaconostoc could not be detected. This was due to the sensitivity of Leaconostoc against the ethanol produced during the alcoholic fermentation, and the growth characteristics of Leaconostoc in the medium tested / Mestrado / Mestre em Ciência de Alimentos

Orientador : Aldo Focesi Junior / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-18T11:26:09Z (GMT). No. of bitstreams: 1 Amazonas_MariaAngelaLopesdeAlmeida_D.pdf: 8072162 bytes, checksum: 306d833807fef1df9778d78273e59d2b (MD5) Previous issue date: 1993 / Resumo: Piruvato descarboxilase (PDC, EC 4.1.1.1) é uma enzima chave no metabolismo do carbono de levedura, direcionando o ácido pirúvico para a produção de etanol. Embora esteja bem estabelecido que a enzima é um tetrâmero de aproximadamente 240 KD, a estrutura das suas subunidades monoméricas é ainda uma questão controvertida. Tanto um como dois tipos de subunidades têm sido descritos, tendo sido identificados até o momento três genes estruturais -- PDC 1, PDC 5 e PDC 6. Esta tese se propôs a contribuir para a elucidação da questão. Experimentos preliminares foram executados visandoestabelecer as condições adequadas à produção e à estabilidade da enzima durante sua purificação e estocagem.Três formas de PDC, separáveis por cromatografia de troca iônica, foram isoladas e as seguintes hipóteses foram levantadas para explicar suas origens: 1. dissociação dímerotetrâmero/holoenzima-apoenzima; 2. fosforilação reversível;3. proteólise; e 4. diferentes subunidades/isoenzimas / Abstract: Pyruvate decarboxylase (PDC, EC 4.1.1.1) is a key enzyme in the yeast carbon metabolism, driving pyruvic acid towards ethanol production. Although it is well established that the enzyme is a tetramer of about 240 KD, its monomeric subunit structure is still a matter of controversy. Either one or two subunit types have been described and three structural genes -- PDC 1, PDC 5 and PDC 6 -- identified so faro This thesis had the aim of contributing for the elucidation of the questiono preliminary experiments were developed to establish the adequate conditions to the enzyme production and stability during its purification and storage. Three types of PDC,separable by ion exchange chromatography, were isolated and the following hypotheses to explain their origin were brought foward: 1.dimer-tetramer/holoenzyme-apoenzyme dissociation;2. reversible phosphorylation; 3.proteolysis;and 4. different subunits/isoenzymes / Doutorado / Doutor em Ciências Biológicas

Orientador : Antonio Claudio Herrera Braga / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-07-19T09:30:50Z (GMT). No. of bitstreams: 1 Harris_MariaInesNogueiradeCamargo_D.pdf: 11436749 bytes, checksum: fb0f1fe7d6fffecdf4143c5eb9a062d0 (MD5) Previous issue date: 1994 / Doutorado

Orientador: Ranulfo Monte Alegre / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-07-20T05:21:24Z (GMT). No. of bitstreams: 1 Sampaio_RomildoMartins_M.pdf: 3460804 bytes, checksum: e7b9b08730b456faf3979edcf9c103dc (MD5) Previous issue date: 1995 / Resumo: Grande número de leveduras, bactérias e fungos, são conhecidos pela capacidade que possuem em consumir diversos tipos de hidrocarbonetos, produzindo biomassa de rica composição proteica. Neste tipo de fermentação, esses microrganismos são também responsáveis pela biodegradação do substrato utilizado, através da produção de um bioemulsificante extracelular no meio de fermentação . Esse mecanismo é importante na limpeza e remoção de poluentes de petróleo de ecossistemas contaminados. A biodegradação é acompanhada pela emulsificação do substrato no meio de crescimento, devido à produção de lipoproteínas e lipopolissacarídeos que atuam reduzindo a tensão interfacial e aumentando a área interfacial do substrato no meio. No presente trabalho, a levedura Saccharomyces lipolytica CCT 0913 (NCYC 825), foi cultivada em meios de cultura contendo óleo-diesel comercial como principal fonte de carbono. A influência de três meios de diferentes composições, três níveis de pH (4,00, 4,50 e 5,00) e duas diferentes concentrações de substrato (3 e 5% de óleo-diesel) na produção do bioemulsificante e no rendimento celular, foram estudados. As fermentações foram primeiramente conduzidas em frascos agitados, e depois, já com as melhores condições operacionais selecionadas, em um fermentador de bancada. Nos frascos agitados, o bioemulsificante produzido apresentou uma maior atividade quando se utilizou pH 5,00 e concentração de substrato de 3%. Para essas condições, os valores de rendimento celular foram de 4,7 g/l, 5,7 g/l e 6,3 g/l para os diferentes meios utilizados. O teor de proteína variou de 39,1% a 39,8% em base seca. Os meios de cultura que continham cloreto de amônio como fonte nitrogenada, mostraram maior eficiência que o meio que continha sulfato de amônio.No fermentador de bancada, as condições operacionais foram pH 5,00, com e sem controle ao longo da fermentação, concentração de substrato de 3% e 5%. Obteve-se uma melhora acentuada na produção de biomassa e do bioemulsificante, e uma redução no tempo total de fermentação. O melhor rendimento celular (8,1 g/l), foi conseguido com pH 5,00 controlado e concentração de substrato de 3%. Por sua vez, as maiores atividades do bioemulsificante foram obtidas com pH 5,00 sem controle, e concentração de substrato de 5% / Abstract: Many yeasts, bacteria and fungi are known for their capacity of assimilating hydrocarbons producing Single Cell Protein (SCP) of rich protein composition. In this type of fermentation these microrganisms are also capable of emulsifying these hydrocarbons due to the production of extracellular bioemulsifier in the fermentation medium. This mechanism is important in the cleaning and removal of petrolleum pollutants of contaminated areas. Biodegradation is due the production of lipoproteins and lipopolyssacharides which reduce the interfacial tension and increase the interfacial area of the substrate in the medium. In the present work, the yeast Saccharomyces lipolytica CCT 0913 (NCYC 825) was cultured in a medium containing comercial diesel-oil as the main carbon source. The influence of three different compositions of the fermentation medium (medium 1,2 and 3), three levels of pH (4.00, 4.50 and 5.00) and two different substrate concentrations (3 and 5% of diesel-oil) in the production of the bioemulsifier and cellular yield were studied. The fermentations were first conducted in shake flasks. With the best conditions obtained in this system, a run was made in a 6 liters fermentation unit. The bioemulsifier produced in the shake flasks showed the higher activity when medium 2 with pH 5.00 and substrate concentration of 3% was utilized. Values for cellular yields under these conditions were 4.7 g/1, 5.3 g/1 and 6.3 g/1 for medium 1, 2 and 3 respectively. Culture medium containing ammonium chloride were more efficient than medium containing ammonium sulphate. Protein yield was 39,1% to 39,8 % (dry basis). Operational conditions in the 6 liters fermentor were pH 5.00 (controlled and not controlled during the fermentation), substrate concentration 3 and 5% and culture medium 2. The best results in the cellular production and the bioemulsifier and also a reduction in the fermentation total time was achieved. The best cellular yield (8.1 g/1) was obtained with the maintenance of pH 5.00 during fermentation and substrate concentration of 3%. The higher bioemulsifier activity were obtained with pH 5.00, not controlled during fermentation, and substrate concentration of 5% / Mestrado / Mestre em Engenharia de Alimentos

Submitted by Fernanda Rodrigues de Lima (fernanda.rlima@ufpe.br) on 2018-10-09T21:10:29Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Dayvison Soares Ferreira.pdf: 1198693 bytes, checksum: 380d0a706f7aa1cc0632a0069ea59a3a (MD5) / Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-11-21T19:33:23Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Dayvison Soares Ferreira.pdf: 1198693 bytes, checksum: 380d0a706f7aa1cc0632a0069ea59a3a (MD5) / Made available in DSpace on 2018-11-21T19:33:23Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Dayvison Soares Ferreira.pdf: 1198693 bytes, checksum: 380d0a706f7aa1cc0632a0069ea59a3a (MD5) Previous issue date: 2015-03-31 / CAPES / A fermentação alcóolica é um processo amplamente usado no setor sucroalcooleiro brasileiro que usa a cana de açúcar como a principal matéria prima e a levedura da espécie Saccharomyces cerevisiae como agente fermentativo. Muito se conhece sobre o funcionamento da fermentação e as diversas variáveis físicas, químicas e biológicas a que ela está sujeita. No entanto, dentre essas variáveis, o papel da suplementação mineral ainda não foi bem esclarecido, fato que se deve as variações na composição química das matérias-primas decorrentes do tipo de solo, variedade da cana de açúcar e suas condições de cultivo. Sabe-se que o uso inadequado da suplementação mineral pode diminuir o rendimento fermentativo, além de causar toxicidade celular nas células de levedura do processo. Por isso, o objetivo desse estudo foi avaliar o efeito do magnésio e do cobre no metabolismo de S. cerevisiae, íons esses comumente usados nas suplementações minerais. As amostras de caldo de cana e melaço utilizadas no estudo foram coletadas em destilarias localizadas na Paraíba e em Pernambuco, respectivamente. Estes meios foram fracionados em duas amostras, uma para a análise da composição mineral de Cu⁺⁺ e Mg⁺⁺ no Instituto de Tecnologia de Pernambuco e a outra para a análise do crescimento celular e realização dos ensaios fermentativos para avaliação dos metabólitos produzidos, como glicerol, ácidos e álcool a partir dos açúcares presentes nos meios. Todos os ensaios foram realizados com a linhagem industrial JP1 da S.cerevisiae por ela ser utilizada com maior frequência em fermentações industriais da região Nordeste. Após os ensaios, constatou-se que o magnésio tem um papel importante no direcionamento metabólico de S.cerevisiae, estimulando a rota fermentativa da levedura e inibindo a produção de biomassa pela célula. Ao se analisar o ensaio fermentativo, verificou-se que os nas amostras de caldo de cana suplementados apresentaram um maior rendimento fermentativo, porém nas amostras de melaço suplementadas, houve uma redução no rendimento fermentativo. Quanto à toxicidade mineral para a levedura, nenhum dos dois minerais testados afetou a viabilidade e o brotamento celular, estas permanecendo com valores > 95% e >5%, respectivamente 20 horas após o término da fermentação. Ao compararmos o efeito do magnésio em diferentes meios de cultura e com diferentes minerais (cálcio e manganês) além do cobre, concluímos que a concentração do magnésio possui uma grande influência no direcionamento metabólico de S. cerevisiae, mais do que a própria concentração mineral no meio. / The alcoholic fermentation is a widely used process in the Brazilian sugar and ethanol industry that uses sugarcane as the main raw material and the yeast Saccharomyces cerevisiae species as fermentation agent. Much is known about the functioning of fermentation and the several variables physical, chemical and biological to which it is subject. However, among these variables, the role of mineral supplementation is not yet well understood, a fact that is due to the variations in the chemical composition of raw materials resulting from soil type, variety of sugarcane and your cultivation. It is known that misuse of mineral supplementation can reduce the fermentative yield and cause cell toxicity in the process the yeast cells. Therefore, the aim of this study was to evaluate the effect of magnesium and copper in the metabolism of S. cerevisiae, these ions commonly used in the mineral supplementation. Samples of sugarcane juice and molasses used in the study were collected in distilleries located in Paraíba and Pernambuco, respectively. These medium were fractionated into two samples, one for analyzing the mineral Cu ++ and Mg ++ composition in Instituto de Tecnologia de Pernambuco and another for analysis of cell growth and carrying out fermentation test for evaluating the produced metabolites such as glycerol, acids and alcohol from the sugars present in the medium. All assays were performed with the JP1 industrial strain of S. cerevisiae because it is used more frequently in industrial fermentations in the Northeast. After the tests, it was found that magnesium has an important role in the metabolic targeting of S. cerevisiae, stimulating the fermentation route and inhibiting yeast biomass production by the cell. When analyzing the fermentation test, it was found that the sugarcane juice supplemented samples exhibited an increased fermentation yield, but in molasses supplemented samples, there was a reduction in fermentation yield. As the mineral toxicity to yeast, neither tested mineral affected cell viability and budding, these remaining values with> 95% and> 5%, respectively, 20 hours after fermentation. Comparing the effect of Mg in different culture media with different mineral (calcium and manganese) in addition to copper, we conclude that the concentration magnesium has a great influence on the metabolic S. cerevisiae targeting more than the actual mineral concentration medium.

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