Visão panorâmica das pesquisas sobre texto no Brasil Visão panorâmica das pesquisas sobre texto no Brasil

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Ingedore G. Villaça Koch

2008-04-01

Full Text Available 0 despertar do interesse, no Brasil, pela abordagem lingilistica do texto - literario ou nio-literario - data do final da decada de 70. Para tanto, contribuiu, de forma significativa, a traducao para o portugues de duas obras sobre o assunto: SemiOtica narrativa e textual (Chabrol et al. 1977, coletanea de trabalhos mais voltados para o escudo da narrativa, entre os quais se podem citar urn do prOprio Chabrol "Alguns problemas de gramatica narrativa e textual" e outro de van Dijk "Gramaticas textuais e estruturas narrativas", este corn urn item sobre Textual (ainda bastante calcado na Gramatica Gerativa e na Semantica LOgica; e LingUtstica e teoria de texto (Schmidt 1978, em que se desenvolve a teoria dos "jogos de atuacio comunicativa", numa perspectiva predominantemente psicossocial.

Efectos de instrumentos odontológicos sobre los marcapasos

OpenAIRE

Gómez Val, Gonzalo

2014-01-01

L’ús del marcapàs ha creat un tipus particular de precaucions postoperatòries. Alguns dels problemes no son coneguts, altres problemes s'han conegut mitjançant els problemes ocorreguts. Actualment, les instruccions dels localitzadors electrònics d’àpex i els piezoelèctrics contraindiquen la seva utilització en pacients portadors de marcapassos, però, aquesta preocupació pel que fa a efectes possibles negatius, està basada en l'especulació sobre el risc potencial de les interferències electro...

Construcionismo social e metapsicologia: um diálogo sobre o conceito de self

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Carla Guanaes

Full Text Available O conceito de self tem sido central nas teorias da psicologia clínica, sendo difícil encontrar, neste campo, estudos que prescindam desta noção. Contudo, alguns teóricos têm questionado concepções mais conhecidas de self, apontando seu caráter construído e situado. Neste artigo, apresentamos o modo como o self tem sido descrito em algumas propostas psicanalíticas e construcionistas sociais, visando a construção de algumas diferenças entre elas. Buscamos, assim, favorecer uma aproximação de estudiosos da área clínica com o construcionismo social, entendendo que esta abordagem favorece uma reflexão sobre o próprio processo de produção de conhecimento sobre o mundo e sobre o self.

As opinioes dos brasileiros sobre ciencia e tecnologia: o paradoxo da relacao entre informacao e atitudes

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Yurij Castelfranchi

2013-11-01

Full Text Available Em muitos debates sobre as relações entre ciência e sociedade, em particular quanto à aceitação das tecnologias ou à percepção de seus riscos, existe uma hipótese subjacente: a de que a ignorância gera medo, e o medo gera desconfiança ou hostilidade contra a ciência e a tecnologia. Neste artigo mostramos que essa hipótese é questionável. Com base numa recente enquete nacional, apontamos que atitudes otimistas sobre ciência e tecnologia não dependem do nível escolar ou da informação declarada ou acessada pelas pessoas sobre o tema. Indivíduos com escassa informação possuem, em geral, atitudes positivas. Pessoas com maior escolaridade e acesso à informação possuem atitudes diversificadas, otimistas sobre alguns aspectos, porém mais críticas sobre outros.

Pensando com Winnicott sobre alguns aspectos relevantes ao processo de ensino e aprendizagem

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Freller Cintia Copit

1999-01-01

Full Text Available Os mecanismos sociais e as práticas educativas produtoras das dificuldades escolares enfrentadas por crianças pobres no Brasil têm sido minuciosamente estudados nas últimas décadas. A partir de observações de cenas escolares e de entrevistas com professores notamos um crescente processo de "coisificação" do professor e do aluno. Quando estes estão destituídos do que lhes é mais pessoal e significativo como seu estilo, ritmo e valores, participam do ritual educativo de forma mecânica, repetitiva e submissa. Refletimos sobre o papel do psicólogo enquanto profissional que pode resgatar, reconhecer e valorizar o indivíduo humano, sua necessidade de se comunicar (ensinar e aprender e seu potencial para isso, participando da recriação da cultura escolar de forma inovadora e singular.

CPO e MID: alguns resultados obtidos em meninos brancos, de 8 a 12 anos DMF and RLM: some results in white children, eight to twelve years old

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José Maria Pacheco de Souza

1973-06-01

Full Text Available São apresentados alguns dados sobre CPO e MID (Índice de ataque ao 1° molar permanente inferior direito. São estudadas as distribuições do MID e do CPO /MID = 0, ajustando-se a binomial e binomial negativa, respectivamente, tendo o teste de aderência acusado bom ajuste em 10 casos, dos 12 testados.Data on DMF and right lower first permanent molar (RLM are presented. Binomial and negative binomial distributions are fitted to the data, and the goodness of fit test indicates good fitting in 10 out of 12 cases.

Skinner e Feyerabend sobre o Método e o Papel da Ciência em uma Sociedade Livre

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Rocha, César Antonio Alves da

2017-01-01

Resumo Da obra de B. F. Skinner fazem parte preocupações de ordem epistemológica, encerrando discussões sobre metodologia e critérios de verdade, e outras de ordem política e social, concernentes à relação entre ciência e sociedade. De um discurso, em alguns aspectos, coincidentes com uma forma de positivismo, Skinner passou a crítico de tendências puramente formalistas sobre o método científico, e de uma defesa do gerenciamento da sociedade por especialistas, passou a uma crítica à centraliz...

A Geografia Crítica Brasileira e o Debate Sobre Ontologia do Espaço: uma Aproximação

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Breno Viotto Pedrosa

2012-06-01

Full Text Available No presente artigo exploraremos alguns aspectos desenvolvidos acerca do tema da ontologia do espaço. Buscaremos explanar sobre os autores que na geografia brasileira se debrucaram sobre o assunto. Esse tema esta ligado a renovacao da geografia critica e ao marxismo, e inicialmente seguiu o itinerario de Armando Correa da Silva, Antonio Carlos Robert Moraes, Milton Santos e Ruy Moreira. Obviamente atualmente muitos outros pesquisadores estudaram a ontologia do espaço. Porém, buscamos tracar quais foram as circunstancias preliminares do surgimento da ideia de ontologia.

Efeitos do cádmio sobre o crescimento das leveduras Saccharomyces cerevisiae PE-2 e Saccharomyces cerevisiae IZ-1904, e a capacidade da vinhaça em atenuar a toxicidade Effect of cadmium on the growth of two Saccharomyces cerevisiae strains, and the vinasse capacity to atenuate the toxicity

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Samuel Mariano-da-Silva

2004-03-01

Full Text Available O presente trabalho teve por finalidade estudar os efeitos do cádmio sobre a levedura Saccharomyces cerevisiae, bem como avaliar a possibilidade de se utilizar a vinhaça como fornecedora de agentes ligantes, visando minimizar os efeitos deletérios do mesmo. Primeiramente montou-se um ensaio visando observar a ação tóxica de diferentes concentrações de cádmio (0; 0,05; 0,1 e 0,5mM, avaliada pelo crescimento de duas cepas da levedura S. cerevisiae (PE-2 e IZ-1904 em meio YED. O meio foi inoculado com 1mL de uma suspensão a 1% (m/v das respectivas cepas e incubado por 18 horas. Em tempos determinados durante o crescimento anaeróbio, alíquotas da suspensão de células foram retiradas e a concentração celular foi determinada. No final do ensaio, foram determinadas a viabilidade celular, a taxa de brotamento e a contaminação bacteriana. Os teores de trealose para cada tratamento, de ambas as cepas, foram dosados no início e no final do ensaio. Em uma segunda etapa, montou-se um ensaio visando avaliar a capacidade da vinhaça (0,15 e 30% do volume do meio em atenuar os efeitos tóxicos de duas doses de cádmio (0,1 e 0,5mM, empregando-se a levedura S. cerevisiae PE-2 em meio YED. O meio foi inoculado com 2mL de uma suspensão a 1% (m/v da levedura e incubado por 18 horas. Em tempos determinados durante o crescimento anaeróbio, alíquotas da suspensão de células foram retiradas e a concentração celular foi determinada. No final do ensaio, foram determinadas a viabilidade celular, a taxa de brotamento, a contaminação bacteriana e a produção de etanol. Os teores de trealose, para cada tratamento, foram dosados nas leveduras no início e no final do ensaio. O cádmio prejudicou o crescimento e a viabilidade celular das duas cepas da levedura S. cerevisiae. A vinhaça apresentou um discreto efeito tóxico, traduzido pela redução do crescimento. Porém, nos tratamentos contaminados com cádmio, apresentou um efeito protetor

El futur de l´educació superior, algunes claus

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Dolors Reig-Hernández

2010-07-01

Full Text Available L'article analitza algunes de les actuals tendències en educació. Comença introduint els canvis produïts en la societat del coneixement, especialment al voltant de les noves abundàncies informatives i formatives que genera, passant després a presentar les diferents teories, les noves abundàncies i narratives que emergeixen entorn de la confluència entre Societat-xarxa i educació. Des d'una perspectiva possibilista es presenten l'Aprenentatge connectat, Aprenentatge Social, Aprenentatge Autònom, Aprenentatge Proactiu i Aprenentatge Informal, detallant els matisos que cadascún aporta al futur de l'educació. Es proposen finalment, adaptats al tema que ens ocupa, alguns valors que poden distingir, en un futur relativament proper, oferta educativa general de difícil supervivència en el nou ecosistema d'oferta educativa excel lent i per tant amb probabilitats de sostenibilitat dins del mateix. 

LA PROTECCIÓN SOCIAL EN AMÉRICA LATINA: alguns puntos sobre los sistemas de pensiones

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Pierre Salama

2009-01-01

Full Text Available Estudio sobre el sistema de protección social en América Latina, con destaque a los sistemas de pensiones. La protección social y las reformas de la Seguridad Social son contextualizadas en el ámbito de las transformaciones productivas, con destaque al proceso de globalización y a la financerización de la economía. Se destacan la intervención masiva y directa del Estado en la economía, en la protección social y su frágil participación en la gestión de la fuerza de trabajo, considerando las particularidades del Estado en América Latina, señalando, aún, la transformación de su papel. Para fundamentación, se utiliza el enfoque “derivacionista” a partir del centro y de la periferia, para destacar los límites de la intervención del Estado para a más de la función de acumulación y legitimación. Se atribuye relieve a la separación de la ciudadanía política de la ciudadanía social, con destaque al desarrollo de la democracia y el avanzo de la pobreza y de la precarización del trabajo.En ese contexto, son inscritas las reformas de la protección social en América Latina, marcadas por la reducción de la solidaridad vertical y horizontal, con fragmentación de las medidas de protección social e ineficiencia el Estado Social, concluyendo con una problematización sobre la relación salarial directa/salarial indirecta.

QUEM PODE FALAR NO FACEBOOK? O “AUTOCONTROLE” EM UM GRUPO SOBRE O PLEBISCITO ACERCA DA DIVISÃO DO ESTADO DO PARÁ

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Ricardo Fabrino Mendonça

2012-12-01

Full Text Available O texto discute a legitimação ou contestação do direito à fala em um grupo do facebook, criado por ocasião do plebiscito sobre a divisão do Pará. Depois de contextualizar o caso, o grupo sob investigação e a metodologia empregada, o artigo analisa as falas e busca estabelecer alguns paralelos entre os argumentos sobre a legitimidade dos falantes e dois corpos de literatura: (1 a discussão sobre a tendência de formação, na internet, de comunidades like-minded; e (2 os debates atuais em torno do conceito de representação política.

L'influx de Hofstadter sobre una versió nova del compatibilisme

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Beltran Munar, Miquel A.

1993-01-01

Una de les idees principals dels llibres més venuts de Hofstadter Gödel, Escher, Bach: un Etern Or Braid és la seva concepció de l'estranya bucle. Aquest article és sobre l'ús que Michael Morden fa d'aquesta idea, tot argumentant a favor de compatibilisme (la doctrina segons la qual el lliure albir és compatible amb el determinisme) contra algunes crítiques formulades pel llibertarisme. Amb la idea de l'auto-referència com a guia, el lliure albir és vist com els símbols de la ment. En ...

Compositions and methods for modeling Saccharomyces cerevisiae metabolism

DEFF Research Database (Denmark)

2012-01-01

The invention provides an in silica model for determining a S. cerevisiae physiological function. The model includes a data structure relating a plurality of S. cerevisiae reactants to a plurality of S. cerevisiae reactions, a constraint set for the plurality of S. cerevisiae reactions, and comma...

Awareness, attitudes and perceptions on epilepsy in Southern Brazil Conhecimento, atitudes e percepções sobre epilepsia no Sul do Brasil

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Asdrubal Falavigna

2007-12-01

Full Text Available OBJECTIVE: To verify awareness and attitudes toward epilepsy in Southern Brazil. METHOD: A questionnaire about familiarity with the disease, awareness and attitudes toward epileptics was applied to 832 inhabitants of Caxias do Sul. The answers were analyzed in three different groups: G1, non-university students; G2, university students up to the second year; and G3, university students with more than two years education and university graduates. RESULTS: University students and graduates are better informed regarding causes and treatment of epilepsy. Moreover, those interviewees present less negative attitudes toward epileptics. However, a large part of that group lacks some basic information on the disease. CONCLUSION: There is lack of information on epilepsy among Brazilians. Education campaigns should be carried out in order to clarify some aspects concerning epilepsy.OBJETIVO: Verificar o conhecimento e as atitudes sobre epilepsia na população de Caxias do Sul. MÉTODO: Foi aplicado um questionário sobre familiaridade com a doença, conhecimentos e atitudes diante de um portador de epilepsia a 832 moradores da cidade. As respostas foram analisadas em três grupos distintos: G1, não-universitários; G2, universitários até o segundo ano; e G3, universitários com mais de dois anos e graduados. RESULTADOS: Os universitários e graduados possuem melhor conhecimento sobre causas e tratamento da epilepsia. Além disso, esses entrevistados apresentam menos atitudes negativas para com o portador de epilepsia. Entretanto, uma boa parte desse grupo apresenta falta de alguns conhecimentos básicos sobre a doença. CONCLUSÃO: Há falta de informação à população brasileira sobre epilepsia. Campanhas educacionais devem ser realizadas no intuito de desmistificar alguns aspectos concernentes à epilepsia.

In vitro screening of probiotic properties of Saccharomyces cerevisiae var. boulardii and food-borne Saccharomyces cerevisiae strains.

Science.gov (United States)

van der Aa Kühle, Alis; Skovgaard, Kerstin; Jespersen, Lene

2005-05-01

The probiotic potential of 18 Saccharomyces cerevisiae strains used for production of foods or beverages or isolated from such, and eight strains of Saccharomyces cerevisiae var. boulardii, was investigated. All strains included were able to withstand pH 2.5 and 0.3% Oxgall. Adhesion to the nontumorigenic porcine jejunal epithelial cell line (IPEC-J2) was investigated by incorporation of 3H-methionine into the yeast cells and use of liquid scintillation counting. Only few of the food-borne S. cerevisiae strains exhibited noteworthy adhesiveness with the strongest levels of adhesion (13.6-16.8%) recorded for two isolates from blue veined cheeses. Merely 25% of the S. cerevisiae var. boulardii strains displayed good adhesive properties (16.2-28.0%). The expression of the proinflammatory cytokine IL-1alpha decreased strikingly in IPEC-J2 cells exposed to a Shiga-like toxin 2e producing Escherichia coli strain when the cells were pre- and coincubated with S. cerevisiae var. boulardii even though this yeast strain was low adhesive (5.4%), suggesting that adhesion is not a mandatory prerequisite for such a probiotic effect. A strain of S. cerevisiae isolated from West African sorghum beer exerted similar effects hence indicating that food-borne strains of S. cerevisiae may possess probiotic properties in spite of low adhesiveness.

[Saccharomyces cerevisiae infections].

Science.gov (United States)

Souza Goebel, Cristine; de Mattos Oliveira, Flávio; Severo, Luiz Carlos

2013-01-01

Saccharomyces cerevisiae is an ubiquitous yeast widely used in industry and it is also a common colonizer of the human mucosae. However, the incidence of invasive infection by these fungi has significantly increased in the last decades. To evaluate the infection by S. cerevisiae in a hospital in southern Brazil during a period of 10 years (2000-2010). Review of medical records of patients infected by this fungus. In this period, 6 patients were found to be infected by S. cerevisiae. The age range of the patients was from 10 years to 84. Urine, blood, ascitic fluid, peritoneal dialysis fluid, and esophageal biopsy samples were analyzed. The predisposing factors were cancer, transplant, surgical procedures, renal failure, use of venous catheters, mechanical ventilation, hospitalization in Intensive Care Unit, diabetes mellitus, chemotherapy, corticosteroid use, and parenteral nutrition. Amphotericin B and fluconazole were the treatments of choice. Three of the patients died and the other 3 were discharged from hospital. We must take special precautions in emerging infections, especially when there are predisposing conditions such as immunosuppression or patients with serious illnesses. The rapid and specific diagnosis of S. cerevisiae infections is important for therapeutic decision. Furthermore, epidemiological and efficacy studies of antifungal agents are necessary for a better therapeutic approach. Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

Effects of fermentation by Saccharomyces cerevisiae and ...

African Journals Online (AJOL)

yassine

2013-02-13

Feb 13, 2013 ... Effect of Saccharomyces cerevisiae fermentation on the ... beetroot, fermentation, Saccharomyces cerevisiae, betalain compounds. ... by Saccharomyces cerevisiae strains (González et al., .... Both red and yellow pigments were influenced during S. .... in beverages such as white wine, grape fruit, and green.

In vitro screening of probiotic properties of Saccharomyces cerevisiae var. boulardii and food-borne Saccharomyces cerevisiae strains

DEFF Research Database (Denmark)

van der Aa Kuhle, Alis; Skovgaard, Kerstin; Jespersen, Lene

2005-01-01

.6-16.8%) recorded for two isolates from blue veined cheeses. Merely 25% of the S. cerevisiae var. boulardii strains displayed good adhesive properties (16.2-28.0%). The expression of the proinflammatory cytokine IL-1α decreased strikingly in IPEC-J2 cells exposed to a Shiga-like toxin 2e producing Escherichia coli...... strain when the cells were pre- and coincubated with S. cerevisiae var. boulardii even though this yeast strain was low adhesive (5.4%), suggesting that adhesion is not a mandatory prerequisite for such a probiotic effect. A strain of S. cerevisiae isolated from West African sorghum beer exerted similar......The probiotic potential of IS Saccharomyces cerevisiae strains used for production of foods or bevel-ages or isolated from such, and eight strains of Saccharomyces cerevisiae var. boulardii, was investigated. All strains included were able to withstand pH 2.5 and 0.3% Ox-all. Adhesion...

Estado e sociedade civil na teoria política: alguns paradigmas, muitas trajetórias

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Raquel Kritsch

2014-12-01

Full Text Available http://dx.doi.org/10.5007/2175-7984.2014v13n28p225 O objetivo primeiro deste artigo é discutir algumas das inúmeras definições elaboradas por pensadores políticos modernos para a noção de sociedade civil e sua particular ligação – de contiguidade ou de oposição – com a ideia de Estado. Tal reconstrução parece relevante para que possamos refletir com certo rigor analítico sobre os muitos usos de sociedade civil, ideia tão cara ao pensamento político e social, tornada hoje quase uma “entidade regulatória”, em nome da qual os mais variados tipos de agentes sociais pretendem falar e cuja vontade supõem ser capazes de interpretar, como bem ilustram os levantes populares recentes ocorridos em várias partes do mundo, inclusive, no Brasil. Para tanto, são apresentados e discutidos alguns dos modelos interpretativos mais conhecidos nas ciências sociais – Hegel, Marx, Gramsci e Habermas e Cohen e Arato – acerca do papel da sociedade civil e sua relação com o âmbito estatal. O intuito é contribuir para o enriquecimento das possibilidades analíticas relacionadas à investigação sobre a agência de atores e movimentos sociais inseridos em coletivos complexamente organizados. Destina-se, assim, principalmente, a servir de orientação teórico-metodológica para alunos de graduação que pretendem pesquisar movimentos sociais em sociedades Contemporâneas.

Sobre o transcendental prático e a dialética da sociabilidade

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Luiz Henrique Lopes dos Santos

2011-07-01

Full Text Available Ao escrever Apresentação do mundo: considerações sobre o pensamento de Ludwig Wittgenstein, as intenções de José Arthur Giannotti não eram principalmente exegéticas. Ele pretendia trilhar alguns caminhos abertos por Ludwig Wittgenstein no intuito de lidar com suas próprias obsessões filosóficas. Neste artigo, mostro por que e como algumas das linhas de pensamento de Wittgenstein ajudaram Giannotti a clarear logicamente alguns de seus próprios temas filosóficos obsessivos: o transcendental prático e a dialética da sociabilidade.In writing Presentation of the World: considerations on the thought of Ludwig Wittgenstein, Giannotti's intentions were not primarily exegetical. He aimed to follow some of Wittgenstein's conceptual pathways in order to deal with his own philosophical obsessions. In this paper, I show why and how some of Wittgenstein's lines of thought helped Giannotti to logically clarify a couple of his own obsessive philosophical themes: the practical transcendental and the dialectic of sociability.

A música no documentário: Um estudo sobre Valsa com Bashir

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Maria Ines Dieuzeide Santos Souza

2011-07-01

Full Text Available Poucos ainda são os estudos em língua portuguesa sobre o papel da música nos filmes de não-ficção. A partir de alguns conceitos de Michel Chion e Anahid Kassabian, no campo do som, dialogando com os estudos de Bill Nichols no campo do documentário, a proposta deste trabalho é refletir sobre as formas e funções da música no discurso documental, especificamente nas experiências recentes de documentários animados, a partir da análise do filme Valsa com Bashir (Ari Folman, 2008. Assim, tentaremos compreender de que maneiras a música se coloca na construção deste tipo de narrativa, e com que elementos ela contribui para as possíveis especificidades do documentário de animação.

O acesso à contracepção de emergência como um direito? Os argumentos do Consórcio Internacional sobre Contracepção de Emergência

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Luíza Lena Bastos

2014-01-01

Full Text Available O Consórcio Internacional sobre Contracepção de Emergência (ICEC tem sido um dos principais difusores da Contracepção de Emergência (CE, um medicamento estratégico para as políticas públicas que envolvem os direitos sexuais e reprodutivos. Ele se constitui em forte interlocutor político e acadêmico, fomentando o debate entre os vários continentes. Este artigo pretende refletir sobre alguns elementos discursivos apresentados pelo consórcio, em seu website, para expandir o acesso à CE.

Efeito do óleo essencial de Eucalyptus globulus sobre espécies produtoras de aflatoxinas

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Georgia Rocha Vilela

2007-01-01

Há relatos na literatura de alguns compostos naturais de plantas que são usados para preservação de alimentos e no controle do desenvolvimento de fungos e bactérias que ocorrem em plantas, grãos, cereais e derivados. O presente trabalho teve como objetivo avaliar "in vitro" o efeito do óleo essencial de Eucalyptus globulus e seu composto majoritário sobre o crescimento micelial dos fungos Aspergillus flavus e Aspergillus parasiticus e a produção de aflatoxinas. A composição química do...

A etnografia das ruas: notas sobre estudar e ser estudado

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Hecht, Tobias

2002-01-01

Full Text Available Passeando entre as notas e as lembranças de dois períodos distintos de trabalho de campo, este ensaio "impressionista" trata da dinâmica em mudança de uma relação de pesquisa com crianças de rua. Em 1992-1993, conduzi trabalho de campo para uma dissertação sobre crianças de rua no nordeste brasileiro. Retornando à região seis anos mais tarde, descobri que a maioria das crianças estudadas apenas uma fração de geração antes estavam então mortas. Estas anotações enfocam minhas conversas com um dos sobreviventes e com quem (e sobre quem estou agora escrevendo uma biografia. Esse esforço colaborativo, voltado de certo modo a reconsiderar as implicações éticas da pesquisa com crianças que levam vidas violentas e vulneráveis, levanta uma gama de novos desafios éticos, alguns dos quais inteiramente imprevistos

A história das relações de raças na América Latina: alguns comentários sobre o estado da pesquisa

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Magnus Mörner

1967-12-01

Full Text Available A notável variedade étnica da América Latina contemporânea òbviamente evoluiu durante o processo histórico que principiou em 1492. Há, talvez, tentação de interpretar tôda a história da Amé-rica Latina em têrmos de relação de raças . Ainda que acreditemos ser isto um absurdo, temos que admitir que as relações de raças influiram em alguns aspectos de sua história. Esta esfera de in-fluência é fàcilmente definida .

Apoptosis - Triggering Effects: UVB-irradiation and Saccharomyces cerevisiae.

Science.gov (United States)

Behzadi, Payam; Behzadi, Elham

2012-12-01

The pathogenic disturbance of Saccharomyces cerevisiae is known as a rare but invasive nosocomial fungal infection. This survey is focused on the evaluation of apoptosis-triggering effects of UVB-irradiation in Saccharomyces cerevisiae. The well-growth colonies of Saccharomyces cerevisiae on Sabouraud Dextrose Agar (SDA) were irradiated within an interval of 10 minutes by UVB-light (302 nm). Subsequently, the harvested DNA molecules of control and UV-exposed yeast colonies were run through the 1% agarose gel electrophoresis comprising the luminescent dye of ethidium bromide. No unusual patterns including DNA laddering bands or smears were detected. The applied procedure for UV exposure was not effective for inducing apoptosis in Saccharomyces cerevisiae. So, it needs another UV-radiation protocol for inducing apoptosis phenomenon in Saccharomyces cerevisiae.

Some epistemology ́s elements of Social Science by Karl PopperAlguns elementos da Epistemolgia da Ciências Sociais de Karl Popper

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Julio Cesar Rodrigues Pereira

2010-12-01

Full Text Available This article discusses the main elements of the epistemology of human sciences of Karl Popper. It was organized as follows. First, we positioned ourselves in the Popper-Adorno controversy. Then weestablished the parameters of discussion, particularly in regards to the idea of “scientific explanation”. Some elements of Popper’s Theory of Knowledge are then analyzed. The final part discusses thescientific parameters of Social Sciences.Este artigo discute os principais elementos da epistemologia das ciências humanas de Karl Popper. Foi organizado como segue. Em primeiro lugar, nos posionamos sobre a  polêmica Popper-Adorno. Então, nós estabelecemos os parâmetros de discussão, nomeadamente no que respeita a idéia de "explicação científica". A seguir são analisados alguns elementos da Teoria do Conhecimento de Popper. A parte final discute os parâmetros científicos de Ciências Sociais

Alguns Rodrigos: relato de viagem sobre a ficcionalização do sujeito

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Rodrigo Barbosa

2017-12-01

Full Text Available Este trabalho investiga as fronteiras e interpenetrações entre a ficção e o real (entre verdade e mentira nas narrativas de si. Observa a distinção aristotélica entre cronistas e poetas; a “literariedade condicional” de textos referenciais e a “literariedade constitutiva” de textos ficcionais, conforme Genette; a divisão de Cosson entre “império dos fatos” e “jardim da imaginação”. Analisa a quebra desta dicotomia pela recepção literária de textos autobiográficos e a provocação trazida pelo conceito de autoficção. Avalia a frequente experiência romanesca contemporânea de transitar entre realidade e invenção. Para análise de textos por este prisma, propõe a ideia de uma “linha da ficcionalidade” e discute os romances Tentativas de capturar o ar, de Flávio Izhaki; Baseado em fatos reais, de Delphine de Vigan; A resistência, de Julián Fuks. Questões sobre a ficcionalização do sujeito, em suas narrativas de vida, são abordadas: a autoficcionalização no cumprimento de seus papéis sociais; a ação do inconsciente nas escolhas narrativas; a invenção da memória. São referenciados autores como Aristóteles, Roland Barthes, Philippe Lejeune, Serge Doubrovski, Mikhail Bakhtin, Gérard Genette, Philippe Gasparini, Silviano Santiago, Eurídice Figueiredo, Evando Nascimento, Manuel Alberca, Anna Faedrich, Rildo Cosson.   --- DOI: http://dx.doi.org/10.12957/matraga.2017.30066

Reflexões sobre avaliação formativa em um curso da Universidade Aberta do Brasil

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Gonzalo Abio

2013-07-01

Full Text Available Neste trabalho queremos mostrar algumas ações avaliativas realizadas com alunos iniciantes de um curso de Pedagogia semipresencial em uma universidade do nordeste brasileiro. Estimamos que o uso de diversos tipos de avaliação e de alguns elementos de uma abordagem andragógica, mais adequada para o perfil maioritário dos alunos participantes, foram elementos favoráveis para o desenvolvimento e resultados do curso. No final, apresentamos algumas considerações gerais sobre avaliação na EaD.

Algunes qüestions clau de protecció de dades al núvol. Cap a una «regulació nebulosa»

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Lorenzo Cotino Hueso

2015-12-01

Full Text Available S'aborden algunes deficiències de la vella i superada regulació nacional i europea de protecció de dades aplicable als serveis del núvol, així com acció d'institucions de protecció de dades per corregir-les. També s'analitza l'esperat reglament europeu de protecció de dades, entre altres aspectes, la seva tendència a reforçar les obligacions del prestador de serveis de núvol, com a «encarregat» de protecció de dades. Igualment s'estudien les exigències respecte del conjunt contractual i la subcontractació de serveis de núvol. L'ús del núvol freqüentment suposa una transferència internacional de dades; sobre això s'aborden vies de flexibilització de la necessitat d'autorització prèvia (a través de les clàusules contractuals tipus i binding corporate rules. Finalment, es valora el paper de la normativa tècnica privada sobre serveis de núvol (com les normes ISO o l’autoregulació del sector i la futura normativa tècnica que haurà d'aprovar o la Comissió Europea o cada Estat, segons com es reguli finalment en el futur reglament europeu. Aquesta coregulació per normativa tècnica pública o privada acaba conformant-se com una regulació més o menys nebulosa.

Ordem e desordem nos labirintos da ficção: os bibliotecários e suas representações em alguns produtos culturais contemporâneos

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Giulia Crippa

Full Text Available Este trabalho, primeiro resultado de uma pesquisa mais ampla, propõe uma indagação sobre alguns aspectos das representações sociais de bibliotecas e bibliotecários em produções literárias e cinematográficas. Surgida com finalidades catalográficas, aos poucos essa indagação revelou elementos que estabeleciam séries diversas, em que o gênero narrativo, tanto literário como cinematográfico, não resultava relevante em relação à representação da biblioteca e do bibliotecário. A presença desses elementos aparenta evidenciar algumas expectativas e utopias em relação ao conhecimento independentemente das narrativas serem ambientadas no passado, no presente ou no futuro, estimulando uma reflexão sobre algumas tradições medievais e barrocas relativas ao universo das bibliotecas e de seus protagonistas, os bibliotecários. Os materiais utilizados foram os filmes "A máquina do tempo", "Farnheit 451", "O dia depois de amanhã", "Star Wars - A Guerra dos clones", e os romances "Martin Éden", "O homem sem qualidades", "A máquina do tempo" e "A sombra do vento".

Uma Reflexão sobre o Planejamento Estratégico

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Débora Ferreira Figueiredo

2009-01-01

Full Text Available O termo planejamento estratégico tem sido muito utilizado por administradores e gerentes de organizações há décadas. Entretanto, o conceito, abrangência e aplicação do termo permanecem ainda obscuros. Com o objetivo de aprofundar a discussão sobre o que é o planejamento estratégico, este artigo problematiza as definições de vários autores e pesquisadores do planejamento estratégico, abordando desde suas primeiras conceituações até alguns dos mais atuais estudos e pesquisas sobre o assunto. Palavras-chave: estratégia, planejamento estratégico, processo de planejamento, formulação de estratégia. Abstract: The term Strategic Planning has been widely used by business heads and managers for decades. However, the concept, scope and aplicability of the term still remain obscure. With the purpose of deepening the discussion about what strategic planning is, this article reflects upon definitions and thoughts of various authors and researchers of strategic planning, from its first concepts to some of the most recent studies and research on the field. Keywords: strategy, strategic planning, planning process, strategy formulation.

Contemplando as imagens do ciborgue: reflexões sobre como vê-las a partir das idéias de Michel Maffesoli

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Nickel, Barbara

2006-01-01

Full Text Available O texto procura apresentar algumas propostas sobre como seria possível estudar as imagens do ciborgue através de uma leitura de Michel Maffesoli. Parte de alguns exemplos para discutir a possibilidade de definição do que seja o ciborgue e, depois, articula-o tanto às noções de imaginário quanto a certas características que o sociólogo francês atribui à pós-modernidade

Gestão da Assistência Farmacêutica: Análise da situação de alguns municípios.

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Fabiola Sulpino VIEIRA

2015-02-01

Full Text Available Os objetivos deste trabalho são descrever e analisar a gestão da assistência farmacêutica em alguns municípios, produzindo mais evidências sobre problemas que podem comprometer o acesso a medicamentos no Sistema Único de Saúde – SUS. Realizou-se pesquisa exploratória, transversal, elaborando-se questionário com questões fechadas sobre a gestão da assistência farmacêutica. O tamanho da amostra foi definido em 431 municípios, selecionados por amostragem aleatória estratificada. Dos 431 municípios, apenas 36 responderam o questionário (8,4%. Destes, 44,4% (n = 16 informaram ter a assistência farmacêutica formalizada, das quais 93,4% (n = 15 contam com pelo menos um farmacêutico. Dos 36 municípios, 97% (n = 35 informaram ter lista de medicamentos para dispensação à população. O controle de estoque foi considerado adequado em 26 deles (72,2%. Estão cumprindo determinação judicial para o fornecimento de medicamentos 14 (38,9% municípios e em 13 deles (36% todas as Unidades Básicas de Saúde – UBS contam com farmacêutico. Os resultados reforçam a necessidade do SUS de avançar no fortalecimento da gestão da assistência farmacêutica a fim de garantir o acesso a medicamentos e a efetividade das ações de saúde.

Heterooligomeric phosphoribosyl diphosphate synthase of Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Hove-Jensen, Bjarne

2004-01-01

The yeast Saccharomyces cerevisiae contains five phosphoribosyl diphosphate (PRPP) synthase-homologous genes (PRS1-5), which specify PRPP synthase subunits 1-5. Expression of the five S. cerevisiae PRS genes individually in an Escherichia coli PRPP-less strain (Deltaprs) showed that a single PRS...

Fatal Saccharomyces Cerevisiae Aortic Graft Infection

Science.gov (United States)

Meyer, Michael (Technical Monitor); Smith, Davey; Metzgar, David; Wills, Christopher; Fierer, Joshua

2002-01-01

Saccharomyces cerevisiae is a yeast commonly used in baking and a frequent colonizer of human mucosal surfaces. It is considered relatively nonpathogenic in immunocompetent adults. We present a case of S. cerevisiae fungemia and aortic graft infection in an immunocompetent adult. This is the first reported case of S. cerevisiue fungemia where the identity of the pathogen was confirmed by rRNA sequencing.

Linguagem e ensino de sociologia: reflexões sobre a apropriação da linguagem sociológica

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Erika Kulessa de Souza

2016-07-01

Full Text Available http://dx.doi.org/10.5007/1806-5023.2016v13n1p141 Neste artigo proponho uma reflexão sobre o aprendizado da Sociologia no Ensino Médio, tendo a linguagem questão central. Considero alguns aspectos da dimensão linguística do ensino e procuro caracterizar a linguagem sociológica e suas relações com o desenvolvimento do olhar sociológico. Recorro às contribuições de Wittgenstein e Vigotski sobre as relações entre pensamento, linguagem e conhecimento, pois apesar de apresentarem concepções de linguagem distintas, e em alguma medida conflitantes, é possível aproximar as implicações que essas duas perspectivas têm para compreender o processo de apropriação da linguagem sociológica.

“Cara ou coroa”: uma provocação sobre educação para índios

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Maria Helena Paes Rodrigues

2003-01-01

Full Text Available O artigo apresenta-se como espaço de reflexão e algumas provocações sobre o “fazer” em educação indígena, tendo como foco de discussão a atual configuração de mundo globalizado que, com o crescente uso da tecnologia, fragiliza fronteiras entre as mais diferentes comunidades. Neste sentido, apresenta uma breve discussão sobre a compreensão de cultura, sob a perspectiva do campo dos Estudos Culturais, destacando a constituição de culturas e identidades híbridas. Localizando a escola enquanto espaço e instituição legitimada de construção e transmissão de verdades e valores simbólicos, discute a função e importância desta para as comunidades indígenas. Assim, levantam-se alguns questionamentos sobre as “verdades” e “valores” dos modelos de escola necessária propostos pelos não-índios para as comunidades indígenas.

A cultura empreendedora nos discursos sobre a juventude

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Julia Salgado

2013-06-01

Full Text Available Neste artigo apresento um exame sobre o discurso da cultura empreendedora em alguns produtos midiáticos. Tendo como pano de fundo a análise comparativa de duas séries televisivas voltadas para o público juvenil em temporalidades distintas (Confissões de Adolescente, de 1994 e Ger@l.com, de 2009/2010, busco examinar as retóricas que, nessas séries e em outros veículos, celebram o empreendedorismo juvenil como resposta às demandas por sucesso pessoal e como solução ao problema do desemprego estrutural. Antes, porém, faço uma contextualização do ambiente social que se construiu a partir da emergência de uma racionalidade neoliberal, procurando, com isso, compreender a relação da cultura empreendedora com lógicas sistêmicas, amplas e dominantes.

Influência da violência conjugal sobre a decisão de abortar

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Vera Lúcia Costa Souza

2000-09-01

Full Text Available Os estudos sobre a violência conjugal contra a mulher tem trazido importantes contribuições para o entendimento dos problemas de saúde, aos quais esta população está exposta, em especial os vinculados à atividade reprodutiva. A necessidade de investigar com mais profundidade os nexos entre a violência e o aborto provocado, têm gerado alguns questionamentos, por exemplo: Será que a decisão de abortar surge no ciclo da violência conjugal como um momento de autonomia da mulher ou estas são forçadas a praticar o aborto? Este estudo qualitativo, tem como objetivo caracterizar as manifestações de violência conjugal entre mulheres internadas em situação de aborto provocado, analisando a influência da violência sobre a decisão de abortar. Pretendendo-se com os resultados ampliar a discussão sobre a violência e o aborto dando visibilidade a estes problemas no âmbito dos serviços de saúde. Também possibilita a reflexão das mulheres sobre a situação de violência a que estão submetidas, através da discussão coletiva das suas histórias de vida que refletem vivências de ameaças, desamor, negligência, violência sexual e agressão física.

Notas sobre a contribuição do desenho industrial á arquitetura e a cidade

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Alessandro Ventura

2000-06-01

Full Text Available A principal preocupação do texto é discutir o uso de técnicas industriais pela arquitetura e refletir sobre suas repercussões na cidade. Nesta discussão procura-se estabelecer uma relação entre as técnicas de projeto do desenho industrial e da arquitetura, focalizando-a dentro de uma forma de pensamento produtivo típico da indústria. Abordamos a idéia de produção na cidade, procurando mostrar que seu desenho é fruto dos produtos que lhe são impostos e não por aqueles gerados por suas necessidades. Discorremos, assim, sobre a influência dos veículos automotores no desenho das cidades e sobre a necessidade de criar limitações a seu uso urbano. Alguns dados sobre a importância da indústria da construção são levantados, comparando-a à vitalidade e à relativa importância da indústria automobilística. Finalizamos abordando o tema da mobilidade, característica típica dos produtos industriais. Esta mobilidade construtiva pode vir a ser um elemento fundamental de inovação urbana e transformar a cidade em fruto de sua própria produção

Pórticos, letreiros, lareiras Le Corbusier e Robert Venturi, sobre simbolismo e velocidade no modernismo

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Rafael Urano Frajndlich

2010-12-01

Full Text Available Este artigo procura investigar a leitura que o arquiteto Robert Venturi faz de alguns traços da obra de Le Corbusier, para conceber suas considerações sobre arquitetura e comunicação. Para isso, foram estudadas, de modo breve, as maneiras como Le Corbusier já fazia uso, em sua obra, de algumas categorias que, posteriormente, seriam atribuídas, excelentemente, aos ditos pós-modernos: a retórica, a alusão, a memória dos centro históricos e dos interiores decorados. Tendo em vista a obra geral do arquiteto suíço, é certo que essas categorias aparecem somente nas entrelinhas de seu projeto modernista de reorganização das cidades. Entretanto, uma leitura de minúcias revela alguns temas – especificamente o interesse de Corbusier nos monumentos de Paris, seus pórticos desenhados na Ville contemporaine (1921, e a lareira com motivos surrealistas na cobertura De Beistegui (1929 que seriam objeto de pleno interesse para historiadores e arquitetos da década de 1960. Justamente, nessa recuperação de traços obscuros de Corbusier, Venturi posiciona alguns de seus temas, especificamente em suas soluções residenciais, privilegiando – e, em alguns casos, mesmo exagerando, a imagem chaminé, duplicando sua altura ou colocando-a como grande ordenadora da planta. Todo esse debate será estudado tendo, como pano de fundo, escritos recentes que realizam um balanço crítico das rupturas engendradas pela dita arquitetura pós-moderna com os modernismos. Fazendo uso de considerações de Andreas Huyssen, Paul Virilio e Beatriz Colomina, entre outros, procurou-se ora delimitar, com maior clareza, a fronteira entre essas duas correntes do século 20, ora diluir seus contornos, revelando semelhanças que, eventualmente, fazem-nas indissociáveis.

Alguns apontamentos sobre a trajetória da Psicologia social comunitária no Brasil

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Mariana Alves Gonçalves

Full Text Available Este artigo aborda a trajetória da Psicologia social comunitária no Brasil tomando como material privilegiado de análise os anais dos encontros nacionais da Associação Brasileira de Psicologia Social (ABRAPSO. O objetivo foi o de historiar os argumentos produzidos por autores da PSC em busca de uma identidade para a área. A análise buscou evidenciar a especificidade da PSC, os objetivos de suas intervenções e a noção de comunidade. Tomamos os anais dos encontros nacionais da ABRAPSO como fonte principal pela importância da associação na produção de dispositivos conceituais e de novas formas de atuação profissional dos psicólogos no Brasil. Concluímos o trabalho indicando a ênfase na diferença e na oposicão entre uma psicologia latino e norte-americana como recurso estratégico de afirmação identitária da área. Apontamos a importância do trabalho em comunidade para a renovação das práticas do psicólogo no Brasil e para a relativa carência de reflexão conceitual sobre a noção de comunidade.

Glucose repression in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Kayikci, Omur; Nielsen, Jens

2015-01-01

Glucose is the primary source of energy for the budding yeast Saccharomyces cerevisiae. Although yeast cells can utilize a wide range of carbon sources, presence of glucose suppresses molecular activities involved in the use of alternate carbon sources as well as it represses respiration and gluc......Glucose is the primary source of energy for the budding yeast Saccharomyces cerevisiae. Although yeast cells can utilize a wide range of carbon sources, presence of glucose suppresses molecular activities involved in the use of alternate carbon sources as well as it represses respiration...

Algumas reflexões teóricas sobre polidez e interação de comunidades migrantes em contexto extra nacionais

OpenAIRE

Pereira, Aguinaldo

2015-01-01

O presente trabalho busca apresentar algumas ideias preliminares da pesquisa em andamento sobre polidez linguística de brasileiros em contexto extra nacional, além de reflexões a respeito da migração brasileira para os Estados Unidos. A proposta para a pesquisa é de um trabalho empírico, no entanto aqui me delimitarei a apresentar algumas reflexões teórico-metodológicas para pesquisas dessa linha de investigação, discutindo alguns pressupostos para correntes de trabalho dessa linha da socioli...

Uma Nota Sobre o Impacto do Comércio Internacional no Crescimento de Economias em Desenvolvimento

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ALEXANDRE LOURES

Full Text Available Esta nota investiga o impacto do comércio internacional sobre o crescimento econômico de um grupo de países em desenvolvimento. Para tanto, emprega-se o modelo estrutural proposto por Anderson et al. (2014. Os resultados indicam que o crescimento é estimulado pelo comércio bilateral. Os exercícios contrafactuais sugerem que a liberalização comercial, seja ela fruto de uma redução dos custos do North American Free Trade Agreement (NAFTA, ou de um processo de hiperglobalização, possui um impacto expressivo e positivo sobre o bem-estar social para alguns dos países analisados. No caso do Brasil, a melhora no bem-estar é de 0,25% e 9,13%, respectivamente. Em geral, os resultados demonstram que o comércio internacional pode ser utilizado como instrumento para alavancar o crescimento do PIB e o bem-estar dos países.

Local isolate of Saccharomyces cerevisiae as biocompetitive agent of Aspergillus flavus

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Eni Kusumaningtyas

2006-12-01

Full Text Available Aspergillus flavus is a toxigenic fungus that contaminates feed and influences the animal health. Saccharomyces cerevisiae can be used as a biocompetitive agent to control the contamination. The ability of local isolate of S. cerevisiae as a biocompetitive agent for A. flavus was evaluated. A. flavus (30ml was swept on Sabouraud dextrose agar (SDA, while S. cerevisiae was swept on its left and right. Plates were incubated at 28oC for nine days. Lytic activity of S. cerevisiae was detected by pouring its suspension on the centre of the cross streaks of A. flavus. Plates were incubated at 28oC for five days. Growth inhibition of A. flavus by S. cerevisiae was determined by mixing the two fungi on Potato dextrose broth and incubated at 28oC for 24 hours. Total colony of A. flavus were then observed at incubation time of 2, 4, 6 and 24 hours by pour plates method on the SDA plates and incubated on 28oC for two days. Growth of hyphae of A. flavus sweep were inhibited with the swept of S. cerevisiae. The width of A. flavus colony treated with S. cerevisiae is narrower (3,02 cm than that of control ( 4,60 cm. The growth of A. flavus was also inhibited on the centre of cross streak where the S. cerevisiae poured. S. cerevisiae gradually reduced the colony number of A. flavus in the mixed culture of broth fungi ie. 14 x 103 CFU/ml while colony number of control is 80 x 103 CFU/ml. Results showed that S. cerevisiae could be used as biocompetitive agent of A. flavus.

Homicídios de adolescentes: refletindo sobre alguns fatores associados Adolescents’ homicide: thinking about some associated factors

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Sergio Kodato

2000-01-01

Full Text Available Este estudo é uma investigação de alguns fatores associados a homicídios praticados contra adolescentes, no município de Ribeirão Preto (SP, onde, no período de 1995 a 1998, foram assassinados 101 adolescentes. A coleta e a análise dos dados foram realizadas através da conjunção das seguintes técnicas: levantamento de dados sociográficos, através da análise dos processos judiciais instaurados no Ministério Público local; observação participante da instituição de internamento no município, destinada para adolescente autor de ato infracional; entrevistas com adolescentes internos pela prática de homicídio (n= 8. Como resultado, pode-se afirmar que as condições de vida que levaram à morte os adolescentes, são fruto de uma sincronização de fatores, onde, além da fragilidade institucional, observa-se como determinantes a disputa pela apropriação de bens materiais, o conflito de interesses financeiros, o tráfico de drogas, e, um modo de relacionamento interpessoal, cuja resolução de situações conflitivas se dá de forma não mediada e violenta.This research is an investigation of some factors associated to homicides committed against adolescents, at the city of Ribeirão Preto (SP, in which, during the period of 1995-1998, 101 children and adolescents were killed. The collect and analysis of data were made throughout the association of the following methods: sociographics data enrollment, analysis of taken lawsuits in the local prosecuting counsel; participant observation of the local internment institution, destined to adolescents authors of infraction acts; interview with intern adolescents for homicide acts (n=8. As a result one may state that the life conditions that ends on death of adolescents are product of a synchronization of factors, where, besides the fragility of institutions, one may observe determinants the dispute for appropriation of goods, conflict of financial interests, drug traffic and, a mode

Apontamentos sobre uma análise do discurso da crítica literária universitária

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Grenissa STAFUZZA

2011-07-01

Full Text Available No presente artigo, tecemos alguns apontamentos sobre uma análise do discurso da crítica literária universitária mostrando uma trajetória de construção do discurso crítico acadêmico especializado na literatura. Para tanto, consideramos a transformação do gênero artigo crítico literário, de autoria de professores universitários, publicados em uma revista especializada, assim como a recepção crítica do escritor James Joyce e de sua obra, ressaltando a sua legitimação na universidade.

Apontamentos sobre uma análise do discurso da crítica literária universitária

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Grenissa STAFUZZA

2013-10-01

Full Text Available No presente artigo, tecemos alguns apontamentos sobre uma análise do discurso da crítica literária universitária mostrando uma trajetória de construção do discurso crítico acadêmico especializado na literatura. Para tanto, consideramos a transformação do gênero artigo crítico literário, de autoria de professores universitários, publicados em uma revista especializada, assim como a recepção crítica do escritor James Joyce e de sua obra, ressaltando a sua legitimação na universidade.

Saccharomyces cerevisiae engineered for xylose metabolism exhibits a respiratory response

Science.gov (United States)

Yong-Su Jin; Jose M. Laplaza; Thomas W. Jeffries

2004-01-01

Native strains of Saccharomyces cerevisiae do not assimilate xylose. S. cerevisiae engineered for D-xylose utilization through the heterologous expression of genes for aldose reductase ( XYL1), xylitol dehydrogenase (XYL2), and D-xylulokinase ( XYL3 or XKS1) produce only limited amounts of ethanol in xylose medium. In recombinant S. cerevisiae expressing XYL1, XYL2,...

O ESTUDO DA LINGUAGEM: CONSIDERAÇÕES SOBRE AS PROPOSTAS DE BRUNER E SKINNER

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Cristiane Oliveira Alves Telles Nunes

2014-02-01

Full Text Available Sabendo-se da importância do desenvolvimento da linguagem para a evolução global do indivíduo e que teóricos como Jerome Bruner e Burrhus Frederic Skinner trouxeram contribuições relevantes para o estudo da linguagem, este artigo tem por objetivo contribuir para a compreensão das obras desses autores, no que diz respeito ao desenvolvimento da linguagem, apresentando possíveis pontos de divergência e de convergência entre eles. Para isso, obras clássicas de Bruner e Skinner sobre o desenvolvimento da linguagem são analisadas, assim como alguns artigos que discutem pontos importantes sobre essa temática. Pontos de divergência são encontrados nas teorias de Bruner e Skinner, tais como a diferença nos termos usados por esses autores para se referirem ao que comumente chama-se de linguagem, assim como o fato de dados de observação sistemática serem utilizados por Bruner em sua obra clássica sobre linguagem, característica não encontrada no livro clássico de Skinner sobre comportamento verbal. No entanto, nota-se, também, pontos de convergência nas obras desses autores, como por exemplo, o aspecto pragmatista da linguagem apontado por ambos, assim como a importância do adulto e da cultura para que a criança desenvolva a linguagem.

A oscilação Antártica-mecanismos físicos e a relação com características atmosféricas sobre a América do Sul/oceanos adjacentes

OpenAIRE

Fernanda Cerqueira Vasconcellos

2012-01-01

A Oscilação Antártica (AAO), também chamada de Modo Anular do Hemisfério Sul (HS), é um padrão de oscilação entre os cinturões de pressão das latitudes médias e altas no HS. Alguns autores indicam uma relação entre o clima da América do Sul (AS) e este padrão. Desta forma, este estudo visa avaliar a influência da AAO sobre a AS e incrementar a análise sobre os mecanismos físicos envolvidos. O objetivo geral desta tese foi analisar a configuração troposférica-estratosférica sobre a AS e oceano...

Effect of Temperature on the Prevalence of Saccharomyces Non cerevisiae Species against a S. cerevisiae Wine Strain in Wine Fermentation: Competition, Physiological Fitness, and Influence in Final Wine Composition

Science.gov (United States)

Alonso-del-Real, Javier; Lairón-Peris, María; Barrio, Eladio; Querol, Amparo

2017-01-01

Saccharomyces cerevisiae is the main microorganism responsible for the fermentation of wine. Nevertheless, in the last years wineries are facing new challenges due to current market demands and climate change effects on the wine quality. New yeast starters formed by non-conventional Saccharomyces species (such as S. uvarum or S. kudriavzevii) or their hybrids (S. cerevisiae x S. uvarum and S. cerevisiae x S. kudriavzevii) can contribute to solve some of these challenges. They exhibit good fermentative capabilities at low temperatures, producing wines with lower alcohol and higher glycerol amounts. However, S. cerevisiae can competitively displace other yeast species from wine fermentations, therefore the use of these new starters requires an analysis of their behavior during competition with S. cerevisiae during wine fermentation. In the present study we analyzed the survival capacity of non-cerevisiae strains in competition with S. cerevisiae during fermentation of synthetic wine must at different temperatures. First, we developed a new method, based on QPCR, to quantify the proportion of different Saccharomyces yeasts in mixed cultures. This method was used to assess the effect of competition on the growth fitness. In addition, fermentation kinetics parameters and final wine compositions were also analyzed. We observed that some cryotolerant Saccharomyces yeasts, particularly S. uvarum, seriously compromised S. cerevisiae fitness during competences at lower temperatures, which explains why S. uvarum can replace S. cerevisiae during wine fermentations in European regions with oceanic and continental climates. From an enological point of view, mixed co-cultures between S. cerevisiae and S. paradoxus or S. eubayanus, deteriorated fermentation parameters and the final product composition compared to single S. cerevisiae inoculation. However, in co-inoculated synthetic must in which S. kudriavzevii or S. uvarum coexisted with S. cerevisiae, there were fermentation

A inesperada descoberta de Otávio Ianni sobre preconceito contra descendentes de imigrantes poloneses em Curitiba

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Márcio de Oliveira

2015-12-01

Full Text Available Resumo Após a pesquisa da Unesco sobre relações raciais no Brasil, Florestan Fernandes organizou e liderou uma jovem equipe para tratar do mesmo tema. A preferência recaiu então sobre os estados da Região Sul do Brasil, que não tinham feito parte da pesquisa original. Escolhidos por Florestan Fernandes, Fernando Henrique Cardoso, Roberto Jardim Moreira e Octávio Ianni fizeram parte dessa equipe. Na distribuição dos estados, coube a Ianni o Paraná e Santa Catarina, esse último conjuntamente com Fernando Henrique. Embora o objetivo da pesquisa fosse demonstrar a existência de preconceito nas relações raciais naqueles estados, Ianni ficou surpreso em descobrir também um novo preconceito, dessa feita contra imigrantes poloneses e seus descendentes, na cidade de Curitiba, capital do Paraná. Ianni investigou inicialmente a questão e publicou alguns artigos a respeito, nos quais tentou explicar o inesperado preconceito. No intuito de dar continuidade e investigar mais a fundo o fenômeno, elaborou e publicou um projeto de pesquisa sobre o tema que, contudo, nunca veio à luz.

Pesquisa sobre mortalidade perinatal no Brasil: revisão da metodologia e dos resultados

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Fonseca Sandra Costa

2004-01-01

Full Text Available A mortalidade perinatal persiste como relevante evento em saúde pública, demandando estudos epidemiológicos, tanto para definir sua magnitude e variações temporais, como para identificar seus determinantes e apontar as intervenções adequadas. Existem ainda questões conceituais e metodológicas controversas, gerando heterogeneidade nos estudos e prováveis vieses. No Brasil, nos últimos anos, desponta uma produção crescente sobre o tema, principalmente no Sudeste e Sul. Foram revistos 24 artigos de 1996 a 2003, focalizando: definições e classificações utilizadas, fontes de dados, desenhos de estudo, formas de aferição das variáveis, modelos de análise estatística e principais resultados. A revisão mostrou a progressiva utilização de bancos de dados informatizados, principalmente o SINASC e o SIM, o pequeno número de estudos sobre natimortalidade, a incorporação ainda incipiente das classificações de causas e a discordância em relação a alguns fatores de risco.

O discurso sobre a terra italiana nas Geórgicas de Virgílio

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Thaíse Pereira Bastos Silva Pio

2017-12-01

Full Text Available As Geórgicas (37-30 a.C. constituem um poema sobre a vida rural e as diversas atividades agrícolas: o cultivo dos cereais, a arboricultura, em especial o cultivo da vinha, a criação dos rebanhos e a apicultura. Cada um dos quatro livros que compõem a obra descreve uma atividade específica, por meio do discurso eminentemente didático. Ao longo da obra, porém, notam-se diversas passagens digressivas, em que o poeta narra sobre outros temas, em geral, de cunho religioso, mitológico e filosófico. Uma destas passagens, conhecida como Laudes Italiae, versos 136 a 176 do II canto, constitui um verdadeiro hino de louvor às terras italianas. Intentamos verificar a relevância de alguns dos temas tratados nos referidos versos das Geórgicas, considerando, sobretudo, o contexto de produção da obra, e buscando compreender o seu significado dentro deste poema didático.

Uma história entre duas erudições - notas sobre algumas práticas e alguns dogmas da atual historiografia francesa

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Jean Glénisson

1977-06-01

Full Text Available (primeiro parágrafo do texto Sobre os problemas filosóficos sem dúvida isto é certo ainda que em toda parte se fale de epistemologia — mas sobre as questões de método? Nunca houve tantos congressos, colóquios, conferências, jornadas, publicações consagradas à metodologia de uma disciplina que assegura ela própria que não excita mais nenhum interesse? Poder-se-ia acreditar estar de volta aos melhores tempos da história "positivista" (somente três quartos de séculos nos separam, quando surgiram, de um e de outro lado do Reno, os Handbücher, Lehrbücher, Grundisse, Introductions e Manuels que descobriram os segre-dos, da fabricação da história triunfante — disciplina mestra de um tempo persuadido de haver descoberto a chave de todas as categorias do conhecimento.

A sericultura no Estado de São Paulo: alguns dados atuais e possibilidades futuras

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Maria Regina da Cunha Rodrigues

1968-03-01

Full Text Available Considerando que tanto no Oriente como no Ocidente, o fornecimento do fio de sêda preocupa os responsáveis por essa milenar fonte de beleza e de lucro — justifica-se que à pauta do II Simpósio Brasil-Japão, sejam trazidos alguns problemas para a reflexão em comum.

Consensos e dissensos sobre a cidade-dormitório: São Gonçalo (RJ, permanências e avanços na condição periférica

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Daniel Pereira Rosa

2017-11-01

Full Text Available Neste artigo, debatemos a urbanização brasileira no século XXI e a heterogeneidade da periferia metropolitana fluminense. Utilizando o exemplo da cidade de São Gonçalo (RJ, listamos referências bibliográficas e apontamos elementos que chamam atenção para a necessidade de entender o papel das cidades periféricas que, apesar da primazia metropolitana, apresentam maior integração com a região metropolitana, compondo uma parte do que alguns autores convencionaram como “periferia integrada”. Como periferia integrada, vemos que os indicadores de mobilidade pendular, o aumento das centralidades, a modernização do território e o índice de desenvolvimento nos obrigam a flexionar alguns consensos sobre essa cidade periférica lida ainda, como cidade-dormitório.

Um Deus com o rosto do Brasil: um estudo exploratório sobre a relação entre imagens e imaginários de Deus na cultura e na pregação evangélico-luterana

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Júlio Cézar Adam

2016-12-01

Full Text Available Este artigo pretende refletir sobre imagens e imaginários de Deus no contexto brasileiro em relação com imagens e imaginários de Deus em prédicas do contexto latino-americano, tomando como exemplo prédicas escritas por ministros/as da Igreja Evangélica de Confissão Luterana no Brasil (IECLB, publicadas no site Göttinger Predigten im Internet. Para análise destas imagens e imaginários de Deus, julgou-se importante, tratar o contexto sociocultural da IECLB – que corresponde, em grande medida, ao contexto do protestantismo histórico no Brasil – e refletir brevemente sobre imagem e imaginário em relação à religião e à teologia, não pretendendo construir uma teoria sobre imagem e imaginário. O artigo divide-se em três partes: na primeira parte apresentam-se aspectos das imagens e dos imaginários de Deus presentes na cultura e religiosidade brasileira, tomando alguns exemplos da cultura pop e do contexto teológico de alguns segmentos eclesiásticos. Na segunda parte, busca-se brevemente por conceitos de imagem, imaginário, averiguando a sua relação com a teologia. Na última parte, analisam-se imagens de Deus em prédicas da IECLB e busca-se refletir sobre o significado destas imagens para a pregação cristã, considerando-se o contexto em que a igreja está inserida. 

Ethics in research with human beings: some issues about Psychology Ética em pesquisa com seres humanos: alguns tópicos sobre a psicologia

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Sílvia Helena Koller

2008-04-01

Full Text Available This paper examines some ethical issues in research with human beings, especially addressing the area of Psychology, such as the use of ethical codes; minimum risk; informed consent; debriefing; confidentiality; and ethical committees. It suggests ways for researchers to increase understanding and the proper use of the ethical codes, to guarantee their own protection, and to avoid abuses of power. Special attention is given to methodological issues related to ethics.Este artigo examina alguns aspectos éticos em pesquisa com seres humanos, especialmente endereçando a área da Psicologia, tais como o uso de resoluções éticas; risco mínimo; consentimento livre e esclarecido; decepção; confidencialidade e atuação de comitês de ética. Sugere caminhos aos pesquisadores para incrementar o entendimento e o uso apropriado de códigos de ética, para garantir sua própria proteção e evitar abuso de poder. Atenção especial é dada a assuntos metodológicos relacionados à ética.

Um estudo sobre a relação entre género dos pais e dos filhos e práticas de estilos parentais

OpenAIRE

Albuquerque, Sandra Daniela Quental de

2016-01-01

As abordagens teóricas sobre os estilos parentais ajudam-nos a compreender tanto a forma como os pais se relacionam com os filhos como alguns dos comportamentos associados às aprendizagens escolares das crianças. A literatura de referência na área (Baumrind, 1966, 1971, 1975) identifica três principais estilos parentais: o democrático ou autoritativo, o autoritário e o permissivo. O estudo teve por objetivos; identificar estilos parentais predominantes de um grupo de pais; analisar a relaç...

[Saccharomyces cerevisiae invasive infection: The first reported case in Morocco].

Science.gov (United States)

Maleb, A; Sebbar, E; Frikh, M; Boubker, S; Moussaoui, A; El Mekkaoui, A; Khannoussi, W; Kharrasse, G; Belefquih, B; Lemnouer, A; Ismaili, Z; Elouennass, M

2017-06-01

Saccharomyces cerevisiae is a cosmopolitan yeast, widely used in agro-alimentary and pharmaceutical industry. Its impact in human pathology is rare, but maybe still underestimated compared to the real situation. This yeast is currently considered as an emerging and opportunistic pathogen. Risk factors are immunosuppression and intravascular device carrying. Fungemias are the most frequent clinical forms. We report the first case of S. cerevisiae invasive infection described in Morocco, and to propose a review of the literature cases of S. cerevisiae infections described worldwide. A 77-year-old patient, with no notable medical history, who was hospitalized for a upper gastrointestinal stenosis secondary to impassable metastatic gastric tumor. Its history was marked by the onset of septic shock, with S. cerevisiae in his urine and in his blood, with arguments for confirmation of invasion: the presence of several risk factors in the patient, positive direct microbiological examination, abundant and exclusive culture of S. cerevisiae from clinical samples. Species identification was confirmed by the study of biochemical characteristics of the isolated yeast. Confirmation of S. cerevisiae infection requires a clinical suspicion in patients with risk factors, but also a correct microbiological diagnosis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Prevalence and susceptibility of Saccharomyces cerevisiae causing vaginitis in Greek women.

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Papaemmanouil, V; Georgogiannis, N; Plega, M; Lalaki, J; Lydakis, D; Dimitriou, M; Papadimitriou, A

2011-12-01

Saccharomyces cerevisiae is an ascomycetous yeast, that is traditionally used in wine bread and beer production. Vaginitis caused by S. cerevisiae is rare. The aim of this study was to evaluate the frequency of S. cerevisiae isolation from the vagina in two groups of women and determined the in vitro susceptibility of this fungus. Vaginal samples were collected from a total of 262 (asymptomatic and symptomatic) women with vaginitis attending the centre of family planning of General hospital of Piraeus. All blastomycetes that isolated from the vaginal samples were examined for microscopic morphological tests and identified by conventional methods: By API 20 C AUX and ID 32 C (Biomerieux). Antifungal susceptibility testing for amphotericin B,fluconazole itraconazole,voriconazole, posaconazole and caspofungin was performed by E -test (Ab BIODIKS SWEDEN) against S. cerevisiae. A total of 16 isolates of S. cerevisiae derived from vaginal sample of the referred women, average 6.10%. Susceptibility of 16 isolates of S. cerevisiae to a variety of antimycotic agents were obtained. So all isolates of S. cerevisiae were resistant to fluconazole, posaconazole and intraconazole, but they were sensitive to voriconazole caspofungin and Amphotericin B which were found sensitive (except 1/16 strains). None of the 16 patients had a history of occupational domestic use of baker's yeast. Vaginitis caused by S. cerevisiae occur, is rising and cannot be ignored. Treatment of Saccharomyces vaginitis constitutes a major challenge and may require selected and often prolonged therapy. Copyright © 2011 Elsevier Ltd. All rights reserved.

O que bilíngues bimodais têm a nos dizer sobre desenvolvimento bilíngue?

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de Quadros, Ronice Müller; Lillo-Martin, Diane; Pichler, Deborah Chen

2013-01-01

O objetivo deste trabalho é apresentar o que as pesquisas que estamos desenvolvendo com crianças ouvintes, filhas de pais surdos, adquirindo Língua Brasileira de Sinais (Libras) e Português e Língua de Sinais Americana (ASL) e Inglês (Lillo-Martin et al. 2010) têm a nos dizer sobre desenvolvimento bilíngue. Os dados deste estudo fazem parte de um banco de dados de interações espontâneas coletadas longitudinalmente, alternando contextos de aquisição da Libras e do português como língua alvo, no Brasil e dados coletados longitudinalmente. nos mesmos contextos, de crianças adquirindo ASL e inglês1. Além disso, há também dados do estudo experimental com testes aplicados nos dois pares de línguas que se agregam ao presente estudo. Uma visão geral dos estudos desenvolvidos sobre a aquisição bilíngue bimodal por crianças ouvintes, filhas de pais surdos, será apresentada e, então, serão expostos alguns aspectos linguísticos deste tipo de aquisição, considerando as discussões sobre aquisição bilíngue a partir da pesquisa realizada. PMID:24431480

Jornalistas que escrevem sobre saúde conhecem a Humanização do Atendimento?

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Concília Ortona

2012-12-01

Full Text Available No Brasil, iniciativas de Humanização no atendimento em saúde são identificadas desde os anos 1990, mas ganharam vulto por meio do Programa Nacional de Humanização da Assistência Hospitalar (PNHAH, ampliado pela Política Nacional de Humanização (PNH. O objetivo deste artigo é identificar a percepção sobre Humanização por parte de alguns jornalistas que escrevem sobre Saúde em importantes publicações paulistas, e no que se constitui, na opinião deles, um atendimento humanizado. A análise do material coletado foi feita segundo referenciais teóricos da Bioética, sob o enfoque de autores como Pellegrino e Thomasma (Ética das Virtudes e Beneficência e Beauchamp e Childress (Principialismo. Resultados: Os pesquisados ainda associam a Humanização às primeiras iniciativas de Humanização, vinculadas a assistência ao parto e pré-natal, além do voluntariado, mas desconhecem a existência de uma política estruturada sobre o tema: nenhum sequer mencionou a PNH; consideram o médico como figura essencial à Humanização da assistência e que, portanto, deveria ser virtuoso; e desejam que o atendimento tenha caráter integral (holístico.

Jornalistas que escrevem sobre saúde conhecem a Humanização do Atendimento?

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Concília Ortona

Full Text Available No Brasil, iniciativas de Humanização no atendimento em saúde são identificadas desde os anos 1990, mas ganharam vulto por meio do Programa Nacional de Humanização da Assistência Hospitalar (PNHAH, ampliado pela Política Nacional de Humanização (PNH. O objetivo deste artigo é identificar a percepção sobre Humanização por parte de alguns jornalistas que escrevem sobre Saúde em importantes publicações paulistas, e no que se constitui, na opinião deles, um atendimento humanizado. A análise do material coletado foi feita segundo referenciais teóricos da Bioética, sob o enfoque de autores como Pellegrino e Thomasma (Ética das Virtudes e Beneficência e Beauchamp e Childress (Principialismo. Resultados: Os pesquisados ainda associam a Humanização às primeiras iniciativas de Humanização, vinculadas a assistência ao parto e pré-natal, além do voluntariado, mas desconhecem a existência de uma política estruturada sobre o tema: nenhum sequer mencionou a PNH; consideram o médico como figura essencial à Humanização da assistência e que, portanto, deveria ser virtuoso; e desejam que o atendimento tenha caráter integral (holístico.

[Urinary infection by Saccharomyces cerevisiae: Emerging yeast?].

Science.gov (United States)

Elkhihal, B; Elhalimi, M; Ghfir, B; Mostachi, A; Lyagoubi, M; Aoufi, S

2015-12-01

Saccharomyces cerevisiae is a commensal yeast of the digestive, respiratory and genito-urinary tract. It is widely used as a probiotic for the treatment of post-antibiotic diarrhea. It most often occurs in immunocompromised patients frequently causing fungemia. We report the case of an adult diabetic patient who had a urinary tract infection due to S. cerevisiae. The disease started with urination associated with urinary frequency burns without fever. The diagnosis was established by the presence of yeasts on direct examination and positivity of culture on Sabouraud-chloramphenicol three times. The auxanogramme gallery (Auxacolor BioRad(®)) allowed the identification of S. cerevisiae. The patient was put on fluconazole with good outcome. This observation points out that this is an opportunistic yeast in immunocompromised patients. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

John Dewey e os embates sobre a psicologia do número

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Rafaela Silva Rabelo

Full Text Available Resumo: O presente artigo teve como foco as representações de John Dewey acerca da educação matemática. Especificamente, teve como objetivo explorar as representações de Dewey sobre o ensino de aritmética e o conceito de número, com base em textos que escreveu após a publicação do manual The psychology of number (TPN, do qual foi coautor. Subsidiaram a análise duas cartas de Dewey em resposta a críticas feitas ao TPN e uma resenha. Alguns dos conceitos mobilizados foram representação, campo e lugar social/institucional, com base em Roger Chartier, Michel de Certeau e Pierre Bourdieu. Ficaram evidentes as disputas entre campos, principalmente entre psicologia e matemática, na determinação de quem possui legitimidade para arbitrar sobre o ensino de aritmética. Também transparecem representações de Dewey acerca da educação matemática, sendo que ele reiterou algumas posições presentes no TPN, como a natureza psíquica do número e a relação com os conceitos de medida e razão.

Response of Saccharomyces cerevisiae to D-limonene-induced oxidative stress.

Science.gov (United States)

Liu, Jidong; Zhu, Yibo; Du, Guocheng; Zhou, Jingwen; Chen, Jian

2013-07-01

In the present study, we investigated the mode of cell response induced by D-limonene in Saccharomyces cerevisiae. D-limonene treatment was found to be accompanied by intracellular accumulation of reactive oxygen species (ROS). Since ROS impair cell membranes, an engineered strain with enhanced membrane biosynthesis exhibited a higher tolerance to D-limonene. Subsequent addition of an ROS scavenger significantly reduced the ROS level and alleviated cell growth inhibition. Thus, D-limonene-induced ROS accumulation plays an important role in cell death in S. cerevisiae. In D-limonene-treated S. cerevisiae strains, higher levels of antioxidants, antioxidant enzymes, and nicotinamide adenine dinucleotide phosphate (NADPH) were synthesized. Quantitative real-time PCR results also verified that D-limonene treatment triggered upregulation of genes involved in the antioxidant system and the regeneration of NADPH at the transcription level in S. cerevisiae. These data indicate that D-limonene treatment results in intracellular ROS accumulation, an important factor in cell death, and several antioxidant mechanisms in S. cerevisiae were enhanced in response to D-limonene treatment.

Noite e dia e alguns monocromos psíquicos Night and day - and some psychical monochromes

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Edson Luiz André de Sousa

2006-06-01

Full Text Available O artigo apresenta uma leitura do conto de Jack London "A sombra e o brilho" mostrando o funcionamento do princípio da mímesis no processo de identificação. Propõe-se a expressão monocromos psíquicos para esses espaços mentais de indiferenciação entre o eu e o Outro. Adota-se a tese de Caillois, que afirma que o eu é permeável ao espaço. Nessa perspectiva, o tema do duplo, amplamente desenvolvido por Freud, é fundamental. Partindo-se de notas sobre o trabalho do fotógrafo cego Bavcar, procura-se mostrar alguns traços da estrutura do olhar. O artigo finaliza mostrando as conexões possíveis dessas reflexões para a prática psicanalítica.The paper presents a reading of Jack London's tale "The Shadow and the brightness", showing how the principle of mimesis works in the process of the identification. We propose to call psychical monochromes the spaces of mental indifference between the self and the other. We follow the thesis of Roger Caillois: "the self is permeable in the space". In this perspective, the subject of the double, developped by Freud is essential. We try to show the dialectic of the structure of the look based in some notes about the work of the blind photographer Bavcar. The article finish with showing the possibles connections of all these points with the clinical work.

Controle de doenças foliares e de flores e qualidade pós-colheita do morangueiro tratado com Saccharomyces cerevisiae Control of leaf and flower diseases and postharvest quality of strawberry plants treated with Saccharomyces cerevisiae

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Alfredo de Gouvea

2009-12-01

Full Text Available O efeito de diferentes preparações de Saccharomyces cerevisiae foi avaliado sobre o desenvolvimento das doenças do morangueiro, como mancha-de-micosferela (Mycosphaerella fragariae, mancha-de-dendrofoma (Dendrophoma obscurans e flor-preta (Colletotrichum acutatum além da qualidade pós-colheita dos frutos. O trabalho foi realizado entre 2004 e 2005 na Universidade Tecnológica Federal do Paraná, Campus Dois Vizinhos. Os tratamentos consistiram de pulverizações semanais de cinco diferentes preparados a partir da levedura S. cerevisiae: suspensão com fermento biológico fresco comercial, suspensão de células de levedura, suspensão autoclavada de células, filtrado de cultura em meio líquido e Agro-MOS®, produto comercial formulado a partir da levedura, além da testemunha com água destilada e do tratamento controle com fungicidas. Nenhuma das preparações apresentou efeito contra a mancha-de-micosferela; preparações com a presença de células vivas e o produto Agro-MOS® apresentaram efeito contra mancha-de-dendrofoma; preparações com suspensão do produto comercial e filtrado de cultura líquida reduziram a incidência de flor-preta em flores e frutos. Preparações de S. cerevisiae com suspensão de células, suspensão autoclavada de células e filtrado de cultura líquida promoveram aumento na produtividade dos morangueiros que variou de 589,6 a 617,8 g planta-1. Preparações de S. cerevisiae, com presença de células vivas ou não, alteraram o metabolismo do morangueiro, aumentando a atividade das enzimas quitinase e glucanase, envolvidas na resistência sistêmica adquirida. Todos os tratamentos, com exceção do tratamento com suspensão autoclavada de células, reduziram a incidência de mofo-cinzento em pós-colheita de frutos.The effect of Saccharomyces cerevisiae was evaluated on the development of strawberry diseases and postharvest quality of fruits. The research was carried out in 2004 and 2005 in Paraná State

Conflitos morais insolúveis e teorias normativas: uma abordagem preliminar sobre consistência moral

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Lauren de Lacerda Nunes

2012-04-01

Full Text Available O presente artigo aborda dois tópicos específicos em ética: o problema dos conflitos morais em filosofia e a questáo da consistência em teorias morais. A relaçáo entre conflitos morais e consistência moral estabelecida neste trabalho foi realizada graças à natureza de alguns tipos de conflitos morais, a saber: os insolúveis ou genuínos - que seráo explicados ao longo do trabalho. Conflitos desse tipo sáo capazes de causar inconsistências nas normas de certos sistemas morais, como por exemplo, os preponderantemente racionalistas. Partindo desse problema, os autores que se dispõe a trabalhar este tema demonstram opiniões divididas: alguns optam por defender a genuinidade dos conflitos morais insolúveis e consideram as eventuais inconsistências na teoria moral como secundárias, enquanto outros optam por salvaguardar a lógica do pensamento e das teorias morais, negando os conflitos morais insolúveis. Este artigo busca esboçar tal “divisáo” entre os autores, ao explorar brevemente as argumentações de ambas as partes. Por fim, fica demonstrado que uma discussáo sobre consistência e conflitos morais precisa considerar tanto a esfera metaética quanto a esfera normativa da ética.

Uma Revisão de Literatura sobre a Definição de Projeto de Vida na Adolescência

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Letícia Lovato Dellazzana-Zanon

2016-10-01

Full Text Available O objetivo deste trabalho foi realizar uma revisão de literatura de artigos sobre projetos de vida na adolescência produzidos de 2000 até 2012 a fim de investigar se pesquisadores interessados na temática apresentam ou não uma definição de projeto de vida e, em caso afirmativo, quais são essas definições. Realizou-se a busca dos artigos na Biblioteca Virtual de Saúde e no PsychNet da American Psychological Association. Consideraram-se apenas os artigos empíricos disponíveis online na íntegra. Identificaram-se 22 artigos. Os resultados indicaram que a maior parte dos estudos (63,6% não apresenta uma definição explícita de projeto de vida. Quando isto ocorre, observou-se que existe uma multiplicidade de definições. Entretanto, observaram-se alguns aspectos comuns entre as considerações sobre projetos de vida nos artigos encontrados.

Investigation of autonomous cell cycle oscillation in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Hansen, Morten Skov

2007-01-01

Autonome Oscillationer i kontinuert kultivering af Saccharomyces cerevisiae Udgangspunktet for dette Ph.d. projekt var at søge at forstå, hvad der gør det muligt at opnå multiple statiske tilstande ved kontinuert kultivering af Saccharomyces cerevisiae med glukose som begrænsende substrat...

Interactions between Lactobacillus kefiranofaciens and Saccharomyces cerevisiae in mixed culture for kefiran production.

Science.gov (United States)

Cheirsilp, Benjamas; Shoji, Hirofumi; Shimizu, Hiroshi; Shioya, Suteaki

2003-01-01

Since a positive effect on the growth and kefiran production of Lactobacillus kefiranofaciens was observed in a mixed culture with Saccharomyces cerevisiae, the elucidation of the interactions between L. kefiranofaciens and S. cerevisiae may lead to higher productivity. Hence, the microbial interaction of each strain was investigated. Apart from the positive effect of a reduction in the amount of lactic acid by S. cerevisiae, a positive effect of S. cerevisiae on the growth and kefiran production of L. kefiranofaciens in a mixed culture was observed. Various experiments were carried out to study this effect. In this study, the observed increase in capsular kefiran in a mixed culture with inactivated S. cerevisiae correlated well to that in an anaerobic mixed culture. Differences in capsular kefiran production were observed for different initial S. cerevisiae concentrations under anaerobic conditions. From these fermentation results, it was concluded that the physical contact with S. cerevisiae mainly enhanced the capsular kefiran production of L. kefiranofaciens in a mixed culture. Therefore, in an anaerobic mixed culture, this direct contact resulted in higher capsular kefiran production than that in pure culture.

Secretory Overexpression of Bacillus thermocatenulatus Lipase in Saccharomyces cerevisiae Using Combinatorial Library Strategy.

Science.gov (United States)

Kajiwara, Shota; Yamada, Ryosuke; Ogino, Hiroyasu

2018-04-10

Simple and cost-effective lipase expression host microorganisms are highly desirable. A combinatorial library strategy is used to improve the secretory expression of lipase from Bacillus thermocatenulatus (BTL2) in the culture supernatant of Saccharomyces cerevisiae. A plasmid library including expression cassettes composed of sequences encoding one of each 15 promoters, 15 secretion signals, and 15 terminators derived from yeast species, S. cerevisiae, Pichia pastoris, and Hansenula polymorpha, is constructed. The S. cerevisiae transformant YPH499/D4, comprising H. polymorpha GAP promoter, S. cerevisiae SAG1 secretion signal, and P. pastoris AOX1 terminator, is selected by high-throughput screening. This transformant expresses BTL2 extra-cellularly with a 130-fold higher than the control strain, comprising S. cerevisiae PGK1 promoter, S. cerevisiae α-factor secretion signal, and S. cerevisiae PGK1 terminator, after cultivation for 72 h. This combinatorial library strategy holds promising potential for application in the optimization of the secretory expression of proteins in yeast. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Oral administration of myostatin-specific recombinant Saccharomyces cerevisiae vaccine in rabbit.

Science.gov (United States)

Liu, Zhongtian; Zhou, Gang; Ren, Chonghua; Xu, Kun; Yan, Qiang; Li, Xinyi; Zhang, Tingting; Zhang, Zhiying

2016-04-29

Yeast is considered as a simple and cost-effective host for protein expression, and our previous studies have proved that Saccharomyces cerevisiae can deliver recombinant protein and DNA into mouse dendritic cells and can further induce immune responses as novel vaccines. In order to know whether similar immune responses can be induced in rabbit by oral administration of such recombinant S. cerevisiae vaccine, we orally fed the rabbits with heat-inactivated myostatin-recombinant S. cerevisiae for 5 weeks, and then myostatin-specific antibody in serum was detected successfully by western blotting and ELISA assay. The rabbits treated with myostatin-recombinant S. cerevisiae vaccine grew faster and their muscles were much heavier than that of the control group. As a common experimental animal and a meat livestock with great economic value, rabbit was proved to be the second animal species that have been successfully orally immunized by recombinant S. cerevisiae vaccine after mice. Copyright © 2016 Elsevier Ltd. All rights reserved.

Saccharomyces cerevisiae var. boulardii fungemia following probiotic treatment

OpenAIRE

Appel-da-Silva, Marcelo C.; Narvaez, Gabriel A.; Perez, Leandro R.R.; Drehmer, Laura; Lewgoy, Jairo

2017-01-01

Probiotics are commonly prescribed as an adjuvant in the treatment of antibiotic-associated diarrhea caused by Clostridium difficile. We report the case of an immunocompromised 73-year-old patient on chemotherapy who developed Saccharomyces cerevisiae var. boulardii fungemia in a central venous catheter during treatment of antibiotic-associated pseudomembranous colitis with the probiotic Saccharomyces cerevisiae var. boulardii. Fungemia was resolved after interruption of probiotic administrat...

Isolation, identification and characterization of regional indigenous Saccharomyces cerevisiae strains

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Hana Šuranská

2016-03-01

Full Text Available Abstract In the present work we isolated and identified various indigenous Saccharomyces cerevisiae strains and screened them for the selected oenological properties. These S. cerevisiae strains were isolated from berries and spontaneously fermented musts. The grape berries (Sauvignon blanc and Pinot noir were grown under the integrated and organic mode of farming in the South Moravia (Czech Republic wine region. Modern genotyping techniques such as PCR-fingerprinting and interdelta PCR typing were employed to differentiate among indigenous S. cerevisiae strains. This combination of the methods provides a rapid and relatively simple approach for identification of yeast of S. cerevisiae at strain level. In total, 120 isolates were identified and grouped by molecular approaches and 45 of the representative strains were tested for selected important oenological properties including ethanol, sulfur dioxide and osmotic stress tolerance, intensity of flocculation and desirable enzymatic activities. Their ability to produce and utilize acetic/malic acid was examined as well; in addition, H2S production as an undesirable property was screened. The oenological characteristics of indigenous isolates were compared to a commercially available S. cerevisiae BS6 strain, which is commonly used as the starter culture. Finally, some indigenous strains coming from organically treated grape berries were chosen for their promising oenological properties and these strains will be used as the starter culture, because application of a selected indigenous S. cerevisiae strain can enhance the regional character of the wines.

Efeitos do conflito armado sobre a vida e a saúde na Colômbia

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Saúl Franco

Full Text Available O presente trabalho trata das conseqüências do conflito armado interno (CAI que a Colômbia tem vivido durante as últimas quatro décadas. Começa identificando o contexto e o momento atual do conflito. A seguir, são descritas algumas das formas, expressões e conseqüências do conflito armado interno, com maior impacto sobre a vida, a qualidade de vida, a saúde e as doenças da população e sobre os serviços de saúde no país. Especial ênfase é dada às altas taxas de mortalidade por homicídio, ao fenômeno do deslocamento forçado pela violência, aos seqüestros e às minas antipessoais. Entre os grupos populacionais mais afetados, destacam-se homens jovens, mulheres, crianças e as minorias étnicas indígenas e afrodescendentes. Esta análise também se refere ao sério problema das contínuas infrações da Lei Internacional Humanitária e aos ataques contra a Missão Médica, assim como às conseqüências negativas do conflito sobre a prestação de serviços de saúde. Para concluir, são feitos alguns comentários gerais sobre a situação descrita e dadas algumas sugestões para o estudo do problema e possíveis ações partindo do setor saúde.

An apoptotic cell cycle mutant in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Villadsen, Ingrid

1996-01-01

The simple eukaryote Saccharomyces cerevisiae has proved to be a useful organism for elucidating the mechanisms that govern cell cycle progression in eukaryotic cells. The excellent in vivo system permits a cell cycle study using temperature sensitive mutants. In addition, it is possible to study...... many genes and gene products from higher eukaryotes in Saccharomyces cerevisiae because many genes and biological processes are homologous or similar in lower and in higher eukaryotes. The highly developed methods of genetics and molecular biology greatly facilitates studies of higher eukaryotic...... processes.Programmmed cell death with apoptosis plays a major role in development and homeostatis in most, if not all, animal cells. Apoptosis is a morphologically distinct form of death, that requires the activation of a highly regulated suicide program. Saccharomyces cerevisiae provides a new system...

Biosorption of the strontium ion by irradiated Saccharomyces cerevisiae under culture conditions.

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Qiu, Liang; Feng, Jundong; Dai, Yaodong; Chang, Shuquan

2017-06-01

As a new-emerging method for strontium disposal, biosorption has shown advantages such as high sorption capacity; low cost. In this study, we investigated the potential of Saccharomyces cerevisiae (S. cerevisiae) in strontium disposal under culture conditions and the effects of irradiation on their biosorption capabilities. We found that S. cerevisiae can survive irradiation and grow. Pre-exposure to irradiation rendered S. cerevisiae resistant to further irradiation. Surprisingly, the pre-exposure to irradiation can increase the biosorption capability of S. cerevisiae. We further investigated the factors that influenced the biosorption efficiency, which were (strongest to weakest): pH > strontium concentration > time > temperature. In our orthogonal experiment, the optimal conditions for strontium biosorption by irradiated S. cerevisiae were: pH 7, 150 mg L -1 strontium at the temperature of 32 °C with 30 h. The equilibrium of strontium biosorption was analyzed by Langmuir and Freundlich models, from which the formal model is found to provide a better fit for the experimental results. The kinetics of strontium biosorption by living irradiated S. cerevisiae was found to be comprised of three phases: dramatically increased during 0-9 h, decreased during 12-24 h, and increased during 30-50 h. These results provide a systematic understanding of the biosorption capabilities of irradiated S. cerevisiae, which can contribute to the development of remediating nuclear waste water. Copyright © 2017 Elsevier Ltd. All rights reserved.

Entre a filosofia e a sociologia: matrizes teóricas das discussões atuais sobre história e memória

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Schmidt, Benito Bisso

2006-01-01

Full Text Available O objetivo deste texto é situar as matrizes teóricas dos trabalhos de alguns autores que servem como referência para boa parte dos estudos contemporâneos sobre as relações entre história e memória: Bergson, Halbwachs, Pollak, Nora e Ricoeur. Seus estudos dialogam, de maneira direta ou indireta, com duas matrizes: a sociológica-objetivista e a fenomenológica-intuicionista. Elas se estabeleceram no âmbito da disputa entre a sociologia e a filosofia pelo direcionamento das ciências humanas nascentes no século XIX

Efficient screening of environmental isolates for Saccharomyces cerevisiae strains that are suitable for brewing.

Science.gov (United States)

Fujihara, Hidehiko; Hino, Mika; Takashita, Hideharu; Kajiwara, Yasuhiro; Okamoto, Keiko; Furukawa, Kensuke

2014-01-01

We developed an efficient screening method for Saccharomyces cerevisiae strains from environmental isolates. MultiPlex PCR was performed targeting four brewing S. cerevisiae genes (SSU1, AWA1, BIO6, and FLO1). At least three genes among the four were amplified from all S. cerevisiae strains. The use of this method allowed us to successfully obtain S. cerevisiae strains.

Revisão bibliográfica sobre espécies do genero Podophyllum

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Paulo Ivo Homem de Bittencourt Júnior

Full Text Available As espécies Podophyllum peltatu. L. (ou Podophyllum callicarpu. Rafin, nativa da America do Norte, Podophyllum emod. Wall. (ou Podophyllum hexandru. Royle, nativa de alguns pontos da Ásia e Podophyllum emod. Wall. var. Chinensi. Sprague,do Extremo Oriente, da família das Berberidacea. tem sido exaustivamente estudadas por causa dos múltiplas propriedades e ações farmacológicas importantes e intensas de raízes e rizomas das mesmas. Esses conhecimentos levaram ao uso antineoplásico, anti-reumático, imunossupressor e sobre disfunções do aparelho digestivo principalmente. A podofilina, resina extraída de tais drogas, vem sendo utilizada sob a forma de extratos fluidos, balsamos, pomadas compostas com outros fármacos e soluções aquosas de alguns glicosideos podofiloderivados. Os principais componentes ativos da podofilina detectados até então foram a podofilotoxona (encontrada em maiores proporções é responsável por grande parte dos efeitos das drogas do gênero, α- e β-peltatinas, podofilotoxona, isopicropodofilona, desox-ipodofilotoxina, desidropofilina, 4'-desmetilpodofilotoxina, 4'desmetilpodofi Zotoxona, 4'-desmetildesoxipodofilotoxina, 4'-desmetilisopicropodofilona e os respectivos a-D-glicosideos. Além disso, foi constatada a presença de alcalóides, compostos nitrogenados, flavonóides, Mg, Mb, Mn, Se e Zn. O levantamento bibliográfico enfoca os estudos relacionando as pesquisas com novos possíveis usos terapêuticos.

Produção do conhecimento sobre o processo de trabalho na enfermagem La producción de conocimiento sobre el proceso de trabajo en enfermería Knowledge production about the work process in nursing

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Flávia Regina Souza Ramos

2009-10-01

Full Text Available Trata de uma reflexão acerca da produção do conhecimento sobre o processo de trabalho, a partir de alguns questionamentos: quem e de onde se fala sobre o trabalho da enfermagem? Destaca-se neste contexto o papel das pós-graduações e da própria ABEn na produção do conhecimento sobre o processo de trabalho. Acerca do papel das pós-graduações, são identificadas as linhas de pesquisa voltadas a esta temática e faz-se uma análise desta produção a partir de estudos realizados por um grupo de pesquisa (Práxis/UFSC, que identificou suas fortalezas e fragilidades em dois estudos acerca da produção do grupo em teses e dissertações. As categorias mais abordadas foram a organização do trabalho, a saúde do trabalhador e alguns temas da relação trabalho e subjetividade; as lacunas se referem a estudos sobre os objetos e os produtos do processo de trabalho; avaliação da qualidade da assistência; necessidades dos sujeitos do cuidado; da finalidade do trabalho e sobre a própria práxis no cenário histórico-social. Finaliza-se reafirmando a importância de pesquisarmos sobre nosso próprio trabalho, em suas múltiplas possibilidades de objetos e abordagens.Esta es una reflexión sobre la producción de conocimiento sobre el proceso de trabajo, a partir de algunas preguntas: ¿quién y dónde hablar de la labor de la enfermería? Es en este contexto el papel de post-graduados y la propria ABEn en la producción de conocimientos sobre el proceso de trabajo. Acerca de la función de post-graduados, se identifican como líneas de investigación dedicados a este tema y es un análisis de la producción de los estudios realizados por un grupo de investigación (Praxis/UFSC, que identifica sus fortalezas y debilidades en dos estudios sobre la producción del grupo en tesis y disertaciones. Las categorías que se trataron fueron la organización de los trabajos, el trabajador de la salud y algunas cuestiones del trabajo y la subjetividad

Conhecimentos e atitudes de adolescentes de uma escola pública sobre a transmissão sexual do HIV

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Ana Clara Patriota Chaves

Full Text Available Os objetivos da pesquisa foram descrever conhecimentos sobre a transmissão do HIV/AIDS e analisar o comportamento sexual e atitudes frente ao uso do preservativo entre adolescentes. Pesquisa exploratória realizada, em 2009, com 234 adolescentes de uma escola em Fortaleza-CE. Utilizou-se questionário semiestruturado e escala de Likert. Os resultados mostraram que 46,6% da amostra já haviam iniciado a vida sexual; 40,7% e 29,5% não usaram preservativo na primeira nem na última relação sexual respectivamente, em decorrência de diversos motivos como não ter o preservativo no momento (27,3%; uso de pílula anticoncepcional (15,2% e confiança no(a parceiro(a (15,2%. Os adolescentes apresentaram dúvidas sobre a transmissão do HIV. As mulheres se mostraram mais favoráveis ao uso do preservativo do que os homens. Conclui-se que o início da vida sexual precoce, as dúvidas sobre a transmissão do HIV e a não utilização efetiva do preservativo são alguns dos fatores que compõem a vulnerabilidade dos jovens.

Functional expression of rat VPAC1 receptor in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Hansen, M.K.; Tams, J.W.; Fahrenkrug, Jan

1999-01-01

G protein-coupled receptor; heterologous expression; membrane protein; Saccharomyces cerevisiae, vasoactive intestinal polypeptide; yeast mating factor-pre-pro *Ga-leader peptide......G protein-coupled receptor; heterologous expression; membrane protein; Saccharomyces cerevisiae, vasoactive intestinal polypeptide; yeast mating factor-pre-pro *Ga-leader peptide...

Creation of a synthetic xylose-inducible promoter for Saccharomyces cerevisiae

Science.gov (United States)

Saccharomyces cerevisiae is currently used to produce ethanol from glucose, but it cannot utilize five-carbon sugars contained in the hemicellulose component of biomass feedstocks. S. cerevisiae strains engineered for xylose fermentation have been made using constitutive promoters to express the req...

Sucrose and Saccharomyces cerevisiae: a relationship most sweet.

Science.gov (United States)

Marques, Wesley Leoricy; Raghavendran, Vijayendran; Stambuk, Boris Ugarte; Gombert, Andreas Karoly

2016-02-01

Sucrose is an abundant, readily available and inexpensive substrate for industrial biotechnology processes and its use is demonstrated with much success in the production of fuel ethanol in Brazil. Saccharomyces cerevisiae, which naturally evolved to efficiently consume sugars such as sucrose, is one of the most important cell factories due to its robustness, stress tolerance, genetic accessibility, simple nutrient requirements and long history as an industrial workhorse. This minireview is focused on sucrose metabolism in S. cerevisiae, a rather unexplored subject in the scientific literature. An analysis of sucrose availability in nature and yeast sugar metabolism was performed, in order to understand the molecular background that makes S. cerevisiae consume this sugar efficiently. A historical overview on the use of sucrose and S. cerevisiae by humans is also presented considering sugarcane and sugarbeet as the main sources of this carbohydrate. Physiological aspects of sucrose consumption are compared with those concerning other economically relevant sugars. Also, metabolic engineering efforts to alter sucrose catabolism are presented in a chronological manner. In spite of its extensive use in yeast-based industries, a lot of basic and applied research on sucrose metabolism is imperative, mainly in fields such as genetics, physiology and metabolic engineering. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Psico-imunologia: Alguns pontos de vista psicológicos e psicopatológicos

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Teixeira, José A. Carvalho

1991-01-01

No presente artigo, o autor faz uma introdução a alguns aspectos psicológicos e psicopatológicos relacionados com a Psico-Imunologia, delimitando esta última em relação a psicologia do stress e A psicossomática. Refere sucintamente as principais correlações entre variáveis psicológicas e imunitárias e, finalmente, tenta individualizar linhas de investigação em Psico-Imunologia que podem ter interesse em Psicologia e Psicopatologia. ABSTRACT: After an introduction ab...

Revisitando alguns conceitos da teoria do apego: comportamento versus representação?

OpenAIRE

Ramires, Vera Regina Röhnelt; Schneider, Michele Scheffel

2010-01-01

Este artigo propõe uma releitura de alguns conceitos da teoria do apego, especialmente os de apego, comportamento de apego e modelo representacional interno. Visa discutir tais conceitos à luz das concepções de Bowlby e de autores contemporâneos. A dicotomia entre comportamento e representação do apego é questionada, bem como a estabilidade e unicidade do modelo representacional interno, com base na análise das contribuições dos principais teóricos desse campo, especialmente na vertente psica...

Removal of Strontium Ions by Immobilized Saccharomyces Cerevisiae in Magnetic Chitosan Microspheres

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Yanan Yin

2017-02-01

Full Text Available A novel biosorbent, immobilized Saccharomyces cerevisiae in magnetic chitosan microspheres was prepared, characterized, and used for the removal of Sr2+ from aqueous solution. The structure and morphology of immobilized S. cerevisiae before and after Sr2+adsorption were observed using scanning electron microscopy with energy dispersive X-ray spectroscopy. The experimental results showed that the Langmuir and Freundlich isotherm models could be used to describe the Sr2+ adsorption onto immobilized S. cerevisiae microspheres. The maximal adsorption capacity (qm was calculated to be 81.96 mg/g by the Langmuir model. Immobilized S. cerevisiae was an effective adsorbent for the Sr2+ removal from aqueous solution.

Habitat Predicts Levels of Genetic Admixture in Saccharomyces cerevisiae

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Viranga Tilakaratna

2017-09-01

Full Text Available Genetic admixture can provide material for populations to adapt to local environments, and this process has played a crucial role in the domestication of plants and animals. The model yeast, Saccharomyces cerevisiae, has been domesticated multiple times for the production of wine, sake, beer, and bread, but the high rate of admixture between yeast lineages has so far been treated as a complication for population genomic analysis. Here, we make use of the low recombination rate at centromeres to investigate admixture in yeast using a classic Bayesian approach and a locus-by-locus phylogenetic approach. Using both approaches, we find that S. cerevisiae from stable oak woodland habitats are less likely to show recent genetic admixture compared with those isolated from transient habitats such as fruits, wine, or human infections. When woodland yeast strains do show recent genetic admixture, the degree of admixture is lower than in strains from other habitats. Furthermore, S. cerevisiae populations from oak woodlands are genetically isolated from each other, with only occasional migration between woodlands and local fruit habitats. Application of the phylogenetic approach suggests that there is a previously undetected population in North Africa that is the closest outgroup to the European S. cerevisiae, including the domesticated Wine population. Careful testing for admixture in S. cerevisiae leads to a better understanding of the underlying population structure of the species and will be important for understanding the selective processes underlying domestication in this economically important species.

Habitat Predicts Levels of Genetic Admixture in Saccharomyces cerevisiae.

Science.gov (United States)

Tilakaratna, Viranga; Bensasson, Douda

2017-09-07

Genetic admixture can provide material for populations to adapt to local environments, and this process has played a crucial role in the domestication of plants and animals. The model yeast, Saccharomyces cerevisiae , has been domesticated multiple times for the production of wine, sake, beer, and bread, but the high rate of admixture between yeast lineages has so far been treated as a complication for population genomic analysis. Here, we make use of the low recombination rate at centromeres to investigate admixture in yeast using a classic Bayesian approach and a locus-by-locus phylogenetic approach. Using both approaches, we find that S. cerevisiae from stable oak woodland habitats are less likely to show recent genetic admixture compared with those isolated from transient habitats such as fruits, wine, or human infections. When woodland yeast strains do show recent genetic admixture, the degree of admixture is lower than in strains from other habitats. Furthermore, S. cerevisiae populations from oak woodlands are genetically isolated from each other, with only occasional migration between woodlands and local fruit habitats. Application of the phylogenetic approach suggests that there is a previously undetected population in North Africa that is the closest outgroup to the European S. cerevisiae , including the domesticated Wine population. Careful testing for admixture in S. cerevisiae leads to a better understanding of the underlying population structure of the species and will be important for understanding the selective processes underlying domestication in this economically important species. Copyright © 2017 Tilakaratna and Bensasson.

Fumaric acid production in Saccharomyces cerevisiae by in silico aided metabolic engineering.

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Guoqiang Xu

Full Text Available Fumaric acid (FA is a promising biomass-derived building-block chemical. Bio-based FA production from renewable feedstock is a promising and sustainable alternative to petroleum-based chemical synthesis. Here we report on FA production by direct fermentation using metabolically engineered Saccharomyces cerevisiae with the aid of in silico analysis of a genome-scale metabolic model. First, FUM1 was selected as the target gene on the basis of extensive literature mining. Flux balance analysis (FBA revealed that FUM1 deletion can lead to FA production and slightly lower growth of S. cerevisiae. The engineered S. cerevisiae strain obtained by deleting FUM1 can produce FA up to a concentration of 610±31 mg L(-1 without any apparent change in growth in fed-batch culture. FT-IR and (1H and (13C NMR spectra confirmed that FA was synthesized by the engineered S. cerevisiae strain. FBA identified pyruvate carboxylase as one of the factors limiting higher FA production. When the RoPYC gene was introduced, S. cerevisiae produced 1134±48 mg L(-1 FA. Furthermore, the final engineered S. cerevisiae strain was able to produce 1675±52 mg L(-1 FA in batch culture when the SFC1 gene encoding a succinate-fumarate transporter was introduced. These results demonstrate that the model shows great predictive capability for metabolic engineering. Moreover, FA production in S. cerevisiae can be efficiently developed with the aid of in silico metabolic engineering.

Skinner: sobre ciência e comportamento humano

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Angelo Augusto Silva Sampaio

Full Text Available Atualmente, não se pode pensar no estudo do comportamento humano sem considerar a abordagem científica a este objeto: o campo da Psicologia científica. Esse campo é disputado por diversos enfoques teóricos que divergem quanto ao modo como definem ciência e comportamento humano. A abordagem de B. F. Skinner foi bastante proeminente no século XX, mas ainda continua a ser mal-entendida. Partindo do desenvolvimento histórico de sua obra, o presente texto visa a iluminar alguns aspectos relacionados às noções de ciência e comportamento humano desse autor e ressaltar as transformações por que passaram. Analisam-se três tópicos da obra de Skinner: seu período inicial (de 1930 a cerca de 1938, a obra "Ciência e Comportamento Humano" de 1953, e as influências da Biologia. São enfatizados aspectos relevantes da sua teorização sobre o tema: busca por relações funcionais, ênfase nos dados empíricos, operacionismo, externalismo, multideterminação do comportamento, experimentalismo, previsão e controle, ética.

Stoichiometric network constraints on xylose metabolism by recombinant Saccharomyces cerevisiae

Science.gov (United States)

Yong-Su Jin; Thomas W. Jeffries

2004-01-01

Metabolic pathway engineering is constrained by the thermodynamic and stoichiometric feasibility of enzymatic activities of introduced genes. Engineering of xylose metabolism in Saccharomyces cerevisiae has focused on introducing genes for the initial xylose assimilation steps from Pichia stipitis, a xylose-fermenting yeast, into S. cerevisiae, a yeast raditionally...

Nos transformamos em brancos: notas sobre a cosmopolítica Mbya Guarani

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Vicente Cretton Pereira

2017-09-01

Full Text Available A partir de alguns contextos específicos de interação com os brancos (jurua procuro investigar no presente trabalho como a cosmopolítica mbya está orientada. A partir de um irônico comentário de uma xamã mbya sobre sua (e de seu grupo transformação corporal em brancos(as, busco entender as relações com o jurua como formas que os Mbya arranjam de experimentar um mundo que os ultrapassa e que, por isso mesmo, desperta seu desejo de modos diversos. Durante encontros lúdicos os Mbya estabeleciam certos laços com os brancos que podem resultar até mesmo em casamento, contudo a tensão que caracteriza a relação com o Outro algumas vezes é resolvida através da guerra ou de tentativas de familiarização.

Removal of strontium ions by immobilized saccharomyces cerevisiae in magnetic chitosan microspheres

Energy Technology Data Exchange (ETDEWEB)

Yin, Yanan; Wang, Jian Long; Yang, Xiao Yong; Li, Weihua [Collaborative Innovation Center for Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing (China)

2017-02-15

A novel biosorbent, immobilized Saccharomyces cerevisiae in magnetic chitosan microspheres was prepared, characterized, and used for the removal of Sr{sup 2+} from aqueous solution. The structure and morphology of immobilized S. cerevisiae before and after Sr{sup 2+}adsorption were observed using scanning electron microscopy with energy dispersive X-ray spectroscopy. The experimental results showed that the Langmuir and Freundlich isotherm models could be used to describe the Sr{sup 2+} adsorption onto immobilized S. cerevisiae microspheres. The maximal adsorption capacity (q{sub m}) was calculated to be 81.96 mg/g by the Langmuir model. Immobilized S. cerevisiae was an effective adsorbent for the Sr{sup 2+} removal from aqueous solution.

Influence of organic acids and organochlorinated insecticides on metabolism of Saccharomyces cerevisiae

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Pejin Dušanka J.

2005-01-01

Full Text Available Saccharomyces cerevisiae is exposed to different stress factors during the production: osmotic, temperature, oxidative. The response to these stresses is the adaptive mechanism of cells. The raw materials Saccharomyces cerevisiae is produced from, contain metabolism products of present microorganisms and protective agents used during the growth of sugar beet for example the influence of acetic and butyric acid and organochlorinated insecticides, lindan and heptachlor, on the metabolism of Saccharomyces cerevisiae was investigated and presented in this work. The mentioned compounds affect negatively the specific growth rate, yield, content of proteins, phosphorus, total ribonucleic acids. These compounds influence the increase of trechalose and glycogen content in the Saccharomyces cerevisiae cells.

The Transcriptional Response of Diverse Saccharomyces cerevisiae Strains to Simulated Microgravity

Science.gov (United States)

Neff, Lily S.; Fleury, Samantha T.; Galazka, Jonathan M.

2018-01-01

Spaceflight imposes multiple stresses on biological systems resulting in genome-scale adaptations. Understanding these adaptations and their underlying molecular mechanisms is important to clarifying and reducing the risks associated with spaceflight. One such risk is infection by microbes present in spacecraft and their associated systems and inhabitants. This risk is compounded by results suggesting that some microbes may exhibit increased virulence after exposure to spaceflight conditions. The yeast, S. cerevisiae, is a powerful microbial model system, and its response to spaceflight has been studied for decades. However, to date, these studies have utilized common lab strains. Yet studies on trait variation in S. cerevisiae demonstrate that these lab strains are not representative of wild yeast and instead respond to environmental stimuli in an atypical manner. Thus, it is not clear how transferable these results are to the wild S. cerevisiae strains likely to be encountered during spaceflight. To determine if diverse S. cerevisiae strains exhibit a conserved response to simulated microgravity, we will utilize a collection of 100 S. cerevisiae strains isolated from clinical, environmental and industrial settings. We will place selected S. cerevisiae strains in simulated microgravity using a high-aspect rotating vessel (HARV) and document their transcriptional response by RNA-sequencing and quantify similarities and differences between strains. Our research will have a strong impact on the understanding of how genetic diversity of microorganisms effects their response to spaceflight, and will serve as a platform for further studies.

Fungal genomics beyond Saccharomyces cerevisiae?

DEFF Research Database (Denmark)

Hofmann, Gerald; Mcintyre, Mhairi; Nielsen, Jens

2003-01-01

Fungi are used extensively in both fundamental research and industrial applications. Saccharomyces cerevisiae has been the model organism for fungal research for many years, particularly in functional genomics. However, considering the diversity within the fungal kingdom, it is obvious...

Construction of killer industrial yeast Saccharomyces cerevisiae HAU-1 and its fermentation performance

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Bijender K. Bajaj

2010-06-01

Full Text Available Saccharomyces cerevisiae HAU-1, a time tested industrial yeast possesses most of the desirable fermentation characteristics like fast growth and fermentation rate, osmotolerance, high ethanol tolerance, ability to ferment molasses, and to ferment at elevated temperatures etc. However, this yeast was found to be sensitive against the killer strains of Saccharomyces cerevisiae. In the present study, killer trait was introduced into Saccharomyces cerevisiae HAU-1 by protoplast fusion with Saccharomyces cerevisiae MTCC 475, a killer strain. The resultant fusants were characterized for desirable fermentation characteristics. All the technologically important characteristics of distillery yeast Saccharomyces cerevisiae HAU-1 were retained in the fusants, and in addition the killer trait was also introduced into them. Further, the killer activity was found to be stably maintained during hostile conditions of ethanol fermentations in dextrose or molasses, and even during biomass recycling.

Crianças negras na história: Fontes e discursos sobre a breve infância permitida pelo escravismo oitocentista brasileiro

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Ione da Silva Jovino

2015-08-01

a literatura de viagem, para, em seguida, buscar em alguns textos de memória. Aspectos da vida infantil, como a brincadeira e a educação, ressaltam que, mesmo de forma limitada e encolhida, foi possível demonstrar que as crianças vivenciavam a experiência da infância, bem como visibilizar suas formas de resistências às imposições dos adultos. Alguns apontamentos sobre educação precedem as notas sobre a relação entre infância e trabalho e a apresentação das percepções da escravidão das crianças de papel, colhidas de textos literários. As considerações finais partem da análise de um conto produzido já no início do século XX, mas que ainda traz resquícios da escravidão, mostrando uma criança negra escravizada, mesmo fora do escravismo formal. Também se considera, apesar da dureza da escravidão, a possibilidade de entrever uma infância-moleque, que é mediadora, brincante, desafiadora, composta de satisfação miúda entre alguns brinquedos, brincadeiras, travessuras e transgressões.

Directed Evolution towards Increased Isoprenoid Production in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Carlsen, Simon; Nielsen, Michael Lynge; Kielland-Brandt, Morten

production can easily be scaled to meet current demands and it is also an environmental benign production method compared to organic synthesis. Thus it would be attractive to engineer a microorganism to produce high amounts of IPP and other immediate prenyl precursors such as geranyl pyrophosphate, farnesyl...... for discovering new genetic perturbations, which would results in and increased production of isoprenoids by S. cerevisiae has been very limited. This project is focus on creating diversity within a lycopene producing S. cerevisiae strain by construction of gDNA-, cDNA-, and transposon-libraries. The diversified...... coloration which is the result of higher amount of lycopene is being produced and hence high amount of isoprenoid precursor being available. This will elucidate novel genetic targets for increasing isoprenoid production in S. cerevisiae...

Saccharomyces cerevisiae var. boulardii fungemia following probiotic treatment

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Marcelo C. Appel-da-Silva

2017-12-01

Full Text Available Probiotics are commonly prescribed as an adjuvant in the treatment of antibiotic-associated diarrhea caused by Clostridium difficile. We report the case of an immunocompromised 73-year-old patient on chemotherapy who developed Saccharomyces cerevisiae var. boulardii fungemia in a central venous catheter during treatment of antibiotic-associated pseudomembranous colitis with the probiotic Saccharomyces cerevisiae var. boulardii. Fungemia was resolved after interruption of probiotic administration without the need to replace the central venous line. Keywords: Saccharomyces, Probiotics, Fungemia, Critical illness, Clostridium difficile

Homo Juridicus: teorização sobre o conceito de indivíduo no âmbito do direito positivo brasileiro

OpenAIRE

Guilherme Frederico Gazineu Rafare

2010-01-01

Este trabalho objetiva a discussão acerca da possibilidade de se utilizar uma tese ontológica sobre o indivíduo no âmbito do Direito. Em primeiro lugar, é feita uma análise histórica de alguns dos conceitos e termos utilizados corriqueiramente pelo Direito e a presença de incerteza terminológica. No Capítulo 2, discute-se a necessidade de uma tese ontológica de indivíduo e a separação entre raciocínio e racionalidade. O Capítulo 3 é dedicado à análise do arcabouço teórico necessário à compree...

A educação para as relações étnico-raciais e os estudos sobre racismo no Brasil

OpenAIRE

Silva, Roberto da; Tobias, Juliano da Silva

2016-01-01

RESUMO Este artigo tem como objetivo fazer a revisão bibliográfica de alguns dos estudos clássicos sobre as relações raciais no Brasil. A revisão engloba o período do início dos anos 30 do século XX até os trabalhos mais recentes, que têm em comum o fato de caracterizarem a discriminação racial como fator importante para a manutenção das desigualdades raciais, reunindo argumentos que fundamentam as reflexões quanto à necessidade da adoção de políticas de ação afirmativa no Brasil, bem como os...

Análise da Expressão dos Genes Relacionados à Parede Celular e à Membrana Plasmática de Saccharomyces Cerevisiae em Resposta a Alta Pressão Hidrostática

OpenAIRE

SOUZA, D. T.

2012-01-01

A levedura Saccharomyces cerevisie é um conhecido microrganismo que recebe grade atenção por sua aplicação biotecnologia industrial. Entretanto, durante o processo industrial, as leveduras ficam expostas aos mais diferentes tipo de estresses. Conhecer os mecanismos de resposta aos diversos estresses é fundamental para obter maiores rendimentos no setor industrial. A alta pressão hidrotática (HHP) é um estresse que exerce um amplo efeito sobre a S. cerevisiae, interferido nas membranas celu...

Metabolic engineering of Saccharomyces cerevisiae for overproduction of triacylglycerols

DEFF Research Database (Denmark)

Ferreira, Raphael; Teixeira, Paulo Goncalves; Gossing, Michael

2018-01-01

Triacylglycerols (TAGs) are valuable versatile compounds that can be used as metabolites for nutrition and health, as well as feedstocks for biofuel production. Although Saccharomyces cerevisiae is the favored microbial cell factory for industrial production of biochemicals, it does not produce...... large amounts of lipids and TAGs comprise only ~1% of its cell dry weight. Here, we engineered S. cerevisiae to reorient its metabolism for overproduction of TAGs, by regulating lipid droplet associated-proteins involved in TAG synthesis and hydrolysis. We implemented a push-and-pull strategy...... PXA1 led to accumulation of  254 mg∙gCDW−1. The TAG levels achieved here are the highest titer reported in S. cerevisiae, reaching 27.4% of the maximum theoretical yield in minimal medium with 2% glucose. This work shows the potential of using an industrially established and robust yeast species...

SORPTION OF Au(III BY Saccharomyces cerevisiae BIOMASS

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Amaria Amaria

2010-07-01

Full Text Available Au(III sorption by S. cerevisiae biomass extracted from beer waste industry was investigated. Experimentally, the sorption was conducted in batch method. This research involved five steps: 1 identification the functional groups present in the S. cerevisiae biomass by infrared spectroscopic technique, 2 determination of optimum pH, 3 determination of the sorption capacity and energy, 4 determination of the sorption type by conducting desorption of sorbed Au(III using specific eluents having different desorption capacity such as H2O (van der Waals, KNO3 (ion exchange, HNO3 (hydrogen bond, and tiourea (coordination bond, 5 determination of effective eluents in Au(III desorption by partial desorption of sorbed Au(III using thiourea, NaCN and KI. The remaining Au(III concentrations in filtrate were analyzed using Atomic Absorption Spectrophotometer. The results showed that: 1 Functional groups of S. cerevisiae biomass that involved in the sorption processes were hydroxyl (-OH, carboxylate (-COO- and amine (-NH2, 2 maximum sorption was occurred at pH 4, equal to 98.19% of total sorption, 3 The sorption capacity of biomass was 133.33 mg/g (6.7682E-04 mol/g and was involved sorption energy 23.03 kJ mol-1, 4 Sorption type was dominated by coordination bond, 5 NaCN was effective eluent to strip Au(III close to 100%.   Keywords: sorption, desorption, S. cerevisiae biomass, Au(III

QUESTÕES SOBRE A PENA DE MORTE

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SOUSA, L.N.

2015-12-01

Full Text Available Pelo menos, desde o Código de Hamurabi as punições para atos desviantes tem sido um foco de reflexão. Este trabalho encerra essa reflexão acerca de aspectos em torno do tema pena de morte. Além de feito político contra o crime, também seria um ato com fins vingativos, fundamentado na violação da dignidade humana, o que justifica a necessidade de haver uma rigorosa análise sobre tal questão, visando os argumentos lógicos, baseados na realidade social brasileira. Alguns estudos demonstram que a percepção da classe menos favorecida é que já existe, de certa forma, uma pena de morte informal no Brasil, praticada pela polícia ou grupos de extermínio. No entanto, diversos setores defendem a pena de morte em nome dos direitos humanos. O debate sobre o referido tema não deve limitar-se às questões relacionadas ao desenvolvimento moral individual, antes deve incluir também a análise de fatores históricos, culturais, econômicos, políticos e ideológicos. Este estudo tem como objetivo coletar dados bibliográficos, bem como dados sobre as opiniões que as pessoas em Campos dos Goytacazes têm sobre a pena de morte. A pesquisa feita é de caráter exploratório. Utilizaram-se as metodologias pertinentes a uma pesquisa bibliográfica. Foi realizada com moradores da cidade de Campos dos Goytacazes/RJ, especificamente com 40 jovens e adultos, de gênero masculino e feminino, com idades entre 18 e 48 anos, sendo a maioria mulheres. A coleta de dados foi feita através de questionários fechados, do tipo likert. Cerca de 48% da amostra concorda com a sentença pena de morte. As respostas quanto a não ter opinião formada sobre o assunto foram minoria, somando 20% ao todo, restando 32% de sujeitos que declararam ser contrários. Metade dos sujeitos não concordou que a sentença seria aplicada corretamente no Brasil. A minoria concordou que a lei teria uma aplicabilidade positiva no país. Aproximadamente 43% dos sujeitos pesquisados

Increased mannoprotein content in wines produced by Saccharomyces kudriavzevii×Saccharomyces cerevisiae hybrids.

Science.gov (United States)

Pérez-Través, Laura; Querol, Amparo; Pérez-Torrado, Roberto

2016-11-21

Several wine quality aspects are influenced by yeast mannoproteins on account of aroma compounds retention, lactic-acid bacterial growth stimulation, protection against protein haze and astringency reduction. Thus selecting a yeast strain that produces high levels of mannoproteins is important for the winemaking industry. In this work, we observed increased levels of mannoproteins in S. cerevisiae×S. kudriavzevii hybrids, compared to the S. cerevisiae strain, in wine fermentations. Furthermore, the expression of a key gene related to mannoproteins biosynthesis, PMT1, increased in the S. cerevisiae×S. kudriavzevii hybrid. We showed that artificially constructed S. cerevisiae×S. kudriavzevii hybrids also increased the levels of mannoproteins. This work demonstrates that either natural or artificial S. cerevisiae×S. kudriavzevii hybrids present mannoprotein overproducing capacity under winemaking conditions, a desirable physiological feature for this industry. These results suggest that genome interaction in hybrids generates a physiological environment that enhances the release of mannoproteins. Copyright © 2016 Elsevier B.V. All rights reserved.

Metabolic Engineering of Saccharomyces cerevisiae Microbial Cell Factories for Succinic Acid Production

DEFF Research Database (Denmark)

Otero, José Manuel; Nielsen, Jens; Olsson, Lisbeth

2007-01-01

anhydride. There are several biomass platforms, all prokaryotic, for succinic acid production; however, overproduction of succinic acid in S. cerevisiae offers distinct process advantages. For example, S. cerevisiae has been awarded GRAS status for use in human consumables, grows well at low p......H significantly minimizing purification and acidification costs associated with organic acid production, and can utilize diverse carbon substrates in chemically defined medium. S. cerevisiae offers the unique advantage of being the most well characterized eukaryotic expression system. Here we describe the use...

Direct conversion of starch to ethanol using recombınant Saccharomyces cerevisiae containing glucoamylase gene

Science.gov (United States)

Purkan, P.; Baktir, A.; Puspaningsih, N. N. T.; Ni'mah, M.

2017-09-01

Saccharomyces cerevisiae is known for its high fermentative capacity, high ethanol yield and its high ethanol tolerance. The yeast is inability converting starch (relatively inexpensive substrate) into biofuel ethanol. Insertion of glucoamylase gene in yeast cell of Saccharomyces cerevisiae had been done to increase the yeast function in ethanol fermentation from starch. Transformation of yeast of S. cerevisiae with recombinant plasmid yEP-GLO1 carrying gene encoding glucoamylase (GLO1) produced the recombinant yeast which enable to degrade starch. Optimizing of bioconversion process of starch into ethanol by the yeast of recombinant Saccharomyces cerevisiae [yEP-GLO1] had been also done. Starch concentration which could be digested by recombinant yeast of S. cerevisiae [yEP-GLO1] was 10% (w/v). Bioconversion of starch having concentration 10% (b/v) using recombinant yeast of S. cerevisiae BY5207 [yEP-GLO1] could result ethanol as 20% (v/v) to alcoholmeter and 19,5% (v/v) to gas of chromatography. Otherwise, using recombinant yeast S. cerevisiae S. cerevisiae AS3324 [yEP-GLO1] resulted ethanol as 17% (v/v) to alcoholmeter and 17,5% (v/v) to gas of chromatography. The highest ethanol in starch bioconversion using both recombinant yeasts BY5207 and AS3324 could be resulted on 144 hours of fermentation time as well as in pH 5.

Zinc oxide and silver nanoparticles toxicity in the baker's yeast, Saccharomyces cerevisiae.

Science.gov (United States)

Galván Márquez, Imelda; Ghiyasvand, Mergan; Massarsky, Andrey; Babu, Mohan; Samanfar, Bahram; Omidi, Katayoun; Moon, Thomas W; Smith, Myron L; Golshani, Ashkan

2018-01-01

Engineered nanomaterials (ENMs) are increasingly incorporated into a variety of commercial applications and consumer products; however, ENMs may possess cytotoxic properties due to their small size. This study assessed the effects of two commonly used ENMs, zinc oxide nanoparticles (ZnONPs) and silver nanoparticles (AgNPs), in the model eukaryote Saccharomyces cerevisiae. A collection of ≈4600 S. cerevisiae deletion mutant strains was used to deduce the genes, whose absence makes S. cerevisiae more prone to the cytotoxic effects of ZnONPs or AgNPs. We demonstrate that S. cerevisiae strains that lack genes involved in transmembrane and membrane transport, cellular ion homeostasis, and cell wall organization or biogenesis exhibited the highest sensitivity to ZnONPs. In contrast, strains that lack genes involved in transcription and RNA processing, cellular respiration, and endocytosis and vesicular transport exhibited the highest sensitivity to AgNPs. Secondary assays confirmed that ZnONPs affected cell wall function and integrity, whereas AgNPs exposure decreased transcription, reduced endocytosis, and led to a dysfunctional electron transport system. This study supports the use of S. cerevisiae Gene Deletion Array as an effective high-throughput technique to determine cellular targets of ENM toxicity.

Alguns apontamentos teóricos sobre a cidade industrial

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Pedro Morais

2014-12-01

estruturas e a multiplicação do solo urbano – e o desenvolvimento dos meios de transportes ferroviários e rodoviários. A combinação de todos estes fatores daria origem a diversas postulações urbanísticas e arquitetônicas, dentre as quais se destacam, em extremos opostos, as cidades-jardins e as torres isoladas em meio a áreas verdes e públicas. O presente artigo parte da convicção de que a atualização das interpretações possíveis de tais acontecimentos e o entendimento de suas bases conceituais à luz das teorias contemporâneas são pontos relevantes no debate de questões que envolvem o manejo e planejamento de um futuro desejável para as metrópoles latino-americanas.

Saccharomyces cerevisiae as a model organism: a comparative study.

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Hiren Karathia

Full Text Available BACKGROUND: Model organisms are used for research because they provide a framework on which to develop and optimize methods that facilitate and standardize analysis. Such organisms should be representative of the living beings for which they are to serve as proxy. However, in practice, a model organism is often selected ad hoc, and without considering its representativeness, because a systematic and rational method to include this consideration in the selection process is still lacking. METHODOLOGY/PRINCIPAL FINDINGS: In this work we propose such a method and apply it in a pilot study of strengths and limitations of Saccharomyces cerevisiae as a model organism. The method relies on the functional classification of proteins into different biological pathways and processes and on full proteome comparisons between the putative model organism and other organisms for which we would like to extrapolate results. Here we compare S. cerevisiae to 704 other organisms from various phyla. For each organism, our results identify the pathways and processes for which S. cerevisiae is predicted to be a good model to extrapolate from. We find that animals in general and Homo sapiens in particular are some of the non-fungal organisms for which S. cerevisiae is likely to be a good model in which to study a significant fraction of common biological processes. We validate our approach by correctly predicting which organisms are phenotypically more distant from S. cerevisiae with respect to several different biological processes. CONCLUSIONS/SIGNIFICANCE: The method we propose could be used to choose appropriate substitute model organisms for the study of biological processes in other species that are harder to study. For example, one could identify appropriate models to study either pathologies in humans or specific biological processes in species with a long development time, such as plants.

Os parâmetros expressivos na execução ao cravo e suas abordagens : um estudo sobre a expressividade cravística = Expressive parameters in the harpsichord performance: a harpsichord expressiveness study

OpenAIRE

Nivia Gasparini Zumpano

2013-01-01

Resumo: O presente trabalho apresenta uma reflexão a respeito da expressividade cravística com ênfase em alguns parâmetros da execução. Para tanto, foram delimitados fatores associados à expressividade a partir da literatura especializada e, na etapa seguinte, realizou-se um estudo sobre sua influência na sonoridade do instrumento, procurando-se destacar questões relativas à possibilidade de dinâmica no cravo. Com o objetivo de verificar a maneira como a expressividade tem sido abordada no co...

Antioxidant properties and global metabolite screening of the probiotic yeast Saccharomyces cerevisiae var. boulardii.

Science.gov (United States)

Datta, Suprama; Timson, David J; Annapure, Uday S

2017-07-01

Saccharomyces cerevisiae var. boulardii is the only yeast species with probiotic properties. It is considered to have therapeutic significance in gastrointestinal disorders. In the present study, a comparative physiological study between this yeast and Saccharomyces cerevisiae (BY4742) was performed by evaluating two prominent traits of probiotic species, responses to different stress conditions and antioxidant capacity. A global metabolite profile was also developed aiming to identify which therapeutically important secondary metabolites are produced. Saccharomyces cerevisiae var. boulardii showed no significant difference in growth patterns but greater stress tolerance compared to S. cerevisiae. It also demonstrated a six- to 10-fold greater antioxidant potential (judged by the 1,1-diphenyl-2-picrylhydrazyl assay), with a 70-fold higher total phenolic content and a 20-fold higher total flavonoid content in the extracellular fraction. These features were clearly differentiated by principal component analysis and further indicated by metabolite profiling. The extracellular fraction of the S. cerevisiae var. boulardii cultures was found to be rich in polyphenolic metabolites: vanillic acid, cinnamic acid, phenyl ethyl alcohol (rose oil), erythromycin, amphetamine and vitamin B 6 , which results in the antioxidant capacity of this strain. The present study presents a new perspective for differentiating the two genetically related strains of yeast, S. cerevisiae and S. cerevisiae var. boulardii by assessing their metabolome fingerprints. In addition to the correlation of the phenotypic properties with the secretory metabolites of these two yeasts, the present study also emphasizes the potential to exploit S. cerevisiae var. boulardii in the industrial production of these metabolites. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Roman Gladiators: some aspects of the shows in the arena in the early Pricipate Gladiadores romanos: alguns aspectos dos espetáculos na arena nos primórdios do Principado

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Renata Senna Garraffoni

2002-11-01

Full Text Available This article discusses the gladiators’ fights and the participation of people from different social classes in these shows. Considering the work by Ellen Meiksins Wood about “the myth of idle mob” in Greece, it is discusses how some scholars have been studying this subject on the Roman world. It also tries to explore some other ways to understand the fights, as shows that fascinated the Romans and had great popularity on the Empire’s daily life.Este artigo consiste em uma reflexão inicial acerca do papel das lutas de gladiadores romanos e da participação das pessoas de diferentes camadas sociais em tais espetáculos. A partir de uma discussão do trabalho de Ellen Meiksins Wood sobre o “mito da plebe desocupada” na Grécia, procuramos discutir como alguns classicistas têm tratado a questão no mundo romano e a possibilidade de trilhar caminhos alternativos para o estudo das lutas, eventos de grande popularidade no cotidiano do Império.

Saccharomyces cerevisiae variety diastaticus friend or foe?-spoilage potential and brewing ability of different Saccharomyces cerevisiae variety diastaticus yeast isolates by genetic, phenotypic and physiological characterization.

Science.gov (United States)

Meier-Dörnberg, Tim; Kory, Oliver Ingo; Jacob, Fritz; Michel, Maximilian; Hutzler, Mathias

2018-06-01

Saccharomyces cerevisiae variety diastaticus is generally considered to be an obligatory spoilage microorganism and spoilage yeast in beer and beer-mixed beverages. Their super-attenuating ability causes increased carbon dioxide concentrations, beer gushing and potential bottle explosion along with changes in flavor, sedimentation and increased turbidity. This research shows clear differences in the super-attenuating properties of S. cerevisiae var. diastaticus yeast strains and their potential for industrial brewing applications. Nineteen unknown spoilage yeast cultures were obtained as isolates and characterized using a broad spectrum of genetic and phenotypic methods. Results indicated that all isolates represent genetically different S. cerevisiae var. diastaticus strains except for strain TUM PI BA 124. Yeast strains were screened for their super-attenuating ability and sporulation. Even if the STA1 gene responsible for super-attenuation by encoding for the enzyme glucoamylase could be verified by real-time polymerase chain reaction, no correlation to the spoilage potential could be demonstrated. Seven strains were further characterized focusing on brewing and sensory properties according to the yeast characterization platform developed by Meier-Dörnberg. Yeast strain TUM 3-H-2 cannot metabolize dextrin and soluble starch and showed no spoilage potential or super-attenuating ability even when the strain belongs to the species S. cerevisiae var. diastaticus. Overall, the beer produced with S. cerevisiae var. diastaticus has a dry and winey body with noticeable phenolic off-flavors desirable in German wheat beers.

Divergence in wine characteristics produced by wild and domesticated strains of Saccharomyces cerevisiae

Science.gov (United States)

Hyma, Katie E; Saerens, Sofie M; Verstrepen, Kevin J; Fay, Justin C

2011-01-01

The budding yeast Saccharomyces cerevisiae is the primary species used by wine makers to convert sugar into alcohol during wine fermentation. Saccharomyces cerevisiae is found in vineyards, but is also found in association with oak trees and other natural sources. Although wild strains of S. cerevisiae as well as other Saccharomyces species are also capable of wine fermentation, a genetically distinct group of S. cerevisiae strains is primarily used to produce wine, consistent with the idea that wine making strains have been domesticated for wine production. In this study, we demonstrate that humans can distinguish between wines produced using wine strains and wild strains of S. cerevisiae as well as its sibling species, Saccharomyces paradoxus. Wine strains produced wine with fruity and floral characteristics, whereas wild strains produced wine with earthy and sulfurous characteristics. The differences that we observe between wine and wild strains provides further evidence that wine strains have evolved phenotypes that are distinct from their wild ancestors and relevant to their use in wine production. PMID:22093681

Functional co-operation between the nuclei of Saccharomyces cerevisiae and mitochondria from other yeast species

DEFF Research Database (Denmark)

Spirek, M.; Horvath, A.; Piskur, Jure

2000-01-01

We elaborated a simple method that allows the transfer of mitochondria from collection yeasts to Saccharomyces cerevisiae. Protoplasts prepared from different yeasts were fused to the protoplasts of the ade2-1, ura3-52, kar1-1, rho (0) strain of S. cerevisiae and were selected for respiring cybrids....... italicus, S, oviformis, S. capensis and S. chevalieri) exhibited complete compatibility with S. cerevisiae nuclei. The closely related S. douglasii mitochondrial genome could also partially restore respiration-deficiency in rho (0) S. cerevisiae, whereas mitochondrial genomes from phylogenetically less...

A Construção do Caso Clínico na Prática Hospitalar: algumas Reflexões Sobre Luto e Toxicomania

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Michelle Karina Silva

2015-06-01

Full Text Available O presente trabalho tem o intuito de discorrer sobre alguns aspectos encontrados em um atendimento psicológico de orientação psicanalítica realizado em ambiente hospitalar. Neste sentido, propõe, a partir da construção do caso clínico, uma reflexão acerca do tema da toxicomania, considerando a relação estabelecida com a vivência do luto no caso da paciente atendida. Após uma caracterização do luto a partir do olhar psicanalítico, enfatiza-se o recurso da toxicomania alcoólica em sua associação com o desamparo reeditado pela perda de um objeto amado. Reflete-se, então, sobre a singularidade da solução encontrada pela paciente, pela via do recurso ao entorpecimento narcótico, na lida com o desenlace gradativo provocado por sucessivas perdas em sua história de vida. Discorre-se, neste sentido, sobre como a saída pelo desprendimento da realidade representado pela toxicomania configura-se como uma resposta possível do sujeito frente à perda de referências e ao desamparo advindos da destruição de laços sociais.

A AUTORIDADE DA IMAGEM TÉCNICA FRENTE A SUA HÍPER OU HIPOSSUFICIÊNCIA: LIMITES E POTÊNCIAS DA IMAGEM DA TECNOIMAGEM

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Prof. Dr. Heinrich Fonteles

2012-09-01

Full Text Available O objetivo deste texto é identificar alguns limites e potências das imagens técnicas para refletirmos sobre a força da imagem visual, assim identifica-se em Wolf (2004 e Aumont (2002 alguns elementos desse poder das imagens da fotografia para associar aos conceitos de imagens visuais pensados por Belting (2008, para depois aproximarmos de algumas ideias de Baitello Jr. (1999 sobre os procedimentos de autenticidade da mídia e de Pross (1972 sobre mídia terciária (TV, e demais autores sobre a imagem técnica para refletirmos sobre a descrição das mesmas nos recortes propostos em estudo. Como foco para pensarmos sobre essas potencialidades, apontaremos esses limites e potências nas intenções da TV Record (diga-se de pronto IURD, ao fazer uso do jornalismo como meio para expandir sua autenticidade via visualidade técnica.

Accumulation of gold using Baker's yeast, Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Roy, Kamalika; Lahiri, Susanta; Sinha, P.

2006-01-01

Authors have reported preconcentration of 152 Eu, a long-lived fission product, by yeast cells, Saccharomyces cerevisiae. Gold being a precious metal is used in electroplating, hydrogenation catalyst, etc. Heterogeneous composition of samples and low concentration offers renewed interest in its selective extraction of gold using various extractants. Gold can be recovered from different solutions using various chemical reagents like amines, organophosphorus compounds, and extractants containing sulphur as donor atom, etc. In the present work, two different strains of baker's yeast, Saccharomyces cerevisiae have been used to study the preconcentration of gold at various experimental conditions

Effects of Saccharomyces cerevisiae or boulardii yeasts on acute stress induced intestinal dysmotility.

Science.gov (United States)

West, Christine; Stanisz, Andrew M; Wong, Annette; Kunze, Wolfgang A

2016-12-28

To investigate the capacity of Saccharomyces cerevisiae ( S. cerevisiae ) and Saccharomyces boulardii ( S. boulardii ) yeasts to reverse or to treat acute stress-related intestinal dysmotility. Adult Swiss Webster mice were stressed for 1 h in a wire-mesh restraint to induce symptoms of intestinal dysmotility and were subsequently killed by cervical dislocation. Jejunal and colon tissue were excised and placed within a tissue perfusion bath in which S. cerevisiae , S. boulardii , or their supernatants were administered into the lumen. Video recordings of contractility and gut diameter changes were converted to spatiotemporal maps and the velocity, frequency, and amplitude of propagating contractile clusters (PCC) were measured. Motility pre- and post-treatment was compared between stressed animals and unstressed controls. S. boulardii and S. cerevisiae helped to mediate the effects of stress on the small and large intestine. Restraint stress reduced jejunal transit velocity (mm/s) from 2.635 ± 0.316 to 1.644 ± 0.238, P boulardii helped to restore jejunal and colonic velocity towards the unstressed controls; 1.833 ± 0.688 to 2.627 ± 0.664, P boulardii or S. cerevisiae supernatants also helped to restore motility to unstressed values in similar capacity. There is a potential therapeutic role for S. cerevisiae and S. boulardii yeasts and their supernatants in the treatment of acute stress-related gut dysmotility.

Fontes nitrogenadas e uso de Sacharomyces cerevisiae em dietas à base de cana-de-açúcar para novilhos: consumo, digestibilidade, balanço nitrogenado e parâmetros ruminais

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Pereira Elzânia Sales

2001-01-01

Full Text Available O objetivo do presente estudo foi avaliar os efeitos das fontes nitrogenadas e o uso de Sacharomyces cerevisiae em dietas à base de cana-de-açúcar sobre os consumos e as digestibilidades aparentes totais e parciais de matéria seca (MS, matéria orgânica (MO, proteína bruta (PB, extrato etéreo (EE, carboidratos totais (CHO, fibra em detergente neutro (FDN e carboidratos não-estruturais (CNE, o balanço nitrogenado e os parâmetros ruminais. Foram utilizados quatro novilhos Holandês-Zebu, fistulados no rúmen e abomaso, alimentados com quatro rações à base de cana-de-açúcar, constituídas de duas fontes nitrogenadas (uréia ou cama de frango combinadas com dois níveis de Sacharomyces cerevisiae (0 e 10 g/dia. Utilizou-se delineamento em quadrado latino 4 x 4. A fibra em detergente neutro indigestível (FDNi foi utilizada como indicador, para determinar as digestibilidades aparentes totais e parciais. Os consumos de MS, MO, EE, CT e CNE não foram influenciados pelas fontes nitrogenadas e pela utilização de Sacharomyces cerevisiae. Os consumos de PB e FDN foram maiores para as dietas suplementadas com cama de frango. Os coeficientes de digestibilidades totais de PB e EE foram maiores para as dietas constituídas de uréia. As digestibilidades aparentes totais de MS, MO, CT e FDN não foram influenciadas pelas fontes nitrogenadas e pela utilização de Sacharomyces cerevisiae. O pH do líquido ruminal decresceu linearmente para as dietas suplementadas com uréia e apresentou comportamento quadrático, quando estas dietas foram combinadas com Sacharomyces cerevisiae. As concentrações de amônia no líquido ruminal apresentaram comportamento quadrático, estimando-se valores máximos de 16,90; 26,12; 18,48; e 14,40 mg/100 mL para os tratamentos constituídos de cana-de-açúcar e uréia; cana-de-açúcar, uréia e Sacharomyces cerevisiae; cana-de-açúcar e cama de frango; e cana-de-açúcar, cama de frango e Sacharomyces cerevisiae

PRODUKSI ETANOL DARI TETES TEBU OLEH Saccharomyces cerevisiae PEMBENTUK FLOK (NRRL – Y 265 (Ethanol Production from Cane Molasses by Flocculant Saccharomyces cerevisiae (NRRL – Y 265

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Agustin Krisna Wardani

2013-08-01

Full Text Available The potential use of sugar cane molasses by flocculant Saccharomyces cerevisiae in ethanol production was investigated. In order to minimize the negative effect of calcium on yeast growth, pretreated sugar cane molasses with dilute acid was performed. The influence of process parameters such as sugar concentration and inoculum concentration were evaluated for enhancing bioethanol production. Result showed that maximum ethanol concentration of 8,792% (b/v was obtained at the best condition of inoculum concentration 10% (v/v and sugar concentration 15% (b/v. Based on the experimental data, maximum yield of ethanol production of 65% was obtained. This result demonstrated the potential of molasses as promising biomass resources for ethanol production. Keywords: Ethanol, preteated cane molasses, flocculant Saccharomyces cerevisiae, fermentation   ABSTRAK Efisiensi produksi bioetanol diperoleh melalui ketepatan pemilihan jenis mikroorganisme, bahan baku, dan kontrol proses fermentasi. Alternatif proses untuk meminimalisasi biaya produksi etanol adalah dengan mengeliminasi tahap pemisahan sentrifugasi sel dari produk karena memerlukan biaya instalasi dan biaya perawatan yang tinggi. Proses sentrifugasi merupakan tahapan penting untuk memisahkan sel mikroba dari medium fermentasi pada produksi bioetanol. Untuk meminimalisir biaya produksi akibat proses tersebut digunakan inokulum Saccharomyces cerevisiae pembentuk flok dan tetes tebu sebagai sumber gula. Penelitian ini bertujuan untuk mendapatkan konsentrasi penambahan inokulum Saccharomyces cerevisiae pembentuk flok dan konsentrasi sumber gula dalam tetes tebu yang tepat dalam produksi etanol yang maksimum. Saccharomyces cerevisiae sebanyak 5%, 10%, dan 15% (v/v diinokulasikan pada medium tetes tebu hasil pretreatment dengan kandungan gula 15%, 20%, dan 25% (b/v pada pH 5. Fermentasi dilakukan pada suhu 30°C dan agitasi 100 rpm selama 72 jam. Etanol tertinggi didapat pada kondisi konsentrasi inokulum

Apontamentos sobre a expansão da graduação tecnológica no Brasil

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José Deribaldo Gomes dos Santos

2016-12-01

Full Text Available Analisa a política de expansão da Educação superior no Brasil que, em tempos de reformas do Estado, opta pela precarização da universidade, enquanto valoriza a expansão da graduação tecnológica, objeto específico desta exposição. A opção teórico-metodológica recai sobre materialismo histórico-dialético, pois, do ponto de vista crítico, tal proposta é a que mais se aproxima da realidade, possibilitando ao investigador chegar o mais próximo possível do objeto estudado. Para efeito desta comunicação, serão recortados e submetidos a uma leitura imanente alguns documentos oficiais, bem como determinadas pesquisas que se empenham em debater o assunto.

Enhancing sesquiterpene production in Saccharomyces cerevisiae through in silico driven metabolic engineering

DEFF Research Database (Denmark)

Asadollahi, Mohammadali; Maury, Jerome; Patil, Kiran Raosaheb

2009-01-01

A genome-scale metabolic model was used to identify new target genes for enhanced biosynthesis of sesquiterpenes in the yeast Saccharomyces cerevisiae. The effect of gene deletions on the flux distributions in the metabolic model of S. cerevisiae was assessed using OptGene as the modeling framework...

Evaluation of Lactobacillus plantarum and Saccharomyces cerevisiae in the Presence of Bifenthrin.

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Đorđević, Tijana M; Đurović-Pejčev, Rada D

2016-06-01

This work describes the effect of insecticide bifenthrin on Lactobacillus plantarum and Saccharomyces cerevisiae. Growths of used microorganisms in growth media supplemented with pesticide were studied. Determination of bacterial and yeast fermentation efficiency in wheat supplemented with bifenthrin was conducted. Additionally, investigation of bifenthrin dissipation during microbiological activity was performed. Experiments applying bifenthrin in different concentrations highlighted a negligible impact of the pesticide on the growth of L. plantarum and S. cerevisiae. This insecticide overall negatively affected the yeast fermentation of wheat, while its presence in wheat had a slight negative impact on lactic acid fermentation. The results of bifenthrin dissipation during lactic acid and yeast fermentations of wheat showed that activities of L. plantarum and S. cerevisiae caused lower pesticide reductions. Average bifenthrin residue reduction within samples fermented with L. plantarum was 5.4 % (maximum ~16 %), while within samples fermented with S. cerevisiae, it was 11.6 % (maximum ~17 %).

Enhancing Fatty Acid Production of Saccharomyces cerevisiae as an Animal Feed Supplement.

Science.gov (United States)

You, Seung Kyou; Joo, Young-Chul; Kang, Dae Hee; Shin, Sang Kyu; Hyeon, Jeong Eun; Woo, Han Min; Um, Youngsoon; Park, Chulhwan; Han, Sung Ok

2017-12-20

Saccharomyces cerevisiae is used for edible purposes, such as human food or as an animal feed supplement. Fatty acids are also beneficial as feed supplements, but S. cerevisiae produces small amounts of fatty acids. In this study, we enhanced fatty acid production of S. cerevisiae by overexpressing acetyl-CoA carboxylase, thioesterase, and malic enzyme associated with fatty acid metabolism. The enhanced strain pAMT showed 2.4-fold higher fatty acids than the wild-type strain. To further increase the fatty acids, various nitrogen sources were analyzed and calcium nitrate was selected as an optimal nitrogen source for fatty acid production. By concentration optimization, 672 mg/L of fatty acids was produced, which was 4.7-fold higher than wild-type strain. These results complement the low level fatty acid production and make it possible to obtain the benefits of fatty acids as an animal feed supplement while, simultaneously, maintaining the advantages of S. cerevisiae.

DESAFIOS À EDUCAÇÃO AMBIENTAL: algumas considerações sobre a efetividade da Lei 9.795/99

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Luiz Eduardo Madeira

2013-04-01

Full Text Available Através dos desafios postos na efetivação da educação formal e não-formal a partir das perspectivas legais instituídas pela Lei 9.795/99, entram em conflito a visão tradicional e a visão critica em relação a transformação da sociedade. Nesse sentido, o presente trabalho vem a problematizar alguns elementos na legislação ambiental citada, com a finalidade de pensar algumas peculiaridades trazidas por essa política educacional de âmbito ambiental. Dessa forma, infere-se a importância de se pensar sobre as possibilidades e fragilidades contidas nessa legislação, para efetivar a educação ambiental como realidade na sociedade brasileira.

Study on biosorption of uranium by alginate immobilized saccharomyces cerevisiae

International Nuclear Information System (INIS)

Wang Baoe; Xu Weichang; Xie Shuibo; Guo Yangbin

2005-01-01

Saccharomyces cerevisiae has great capability of biosorption of uranium. The maxium uptake is 172.4 mg/g according to this study. To adapt to the application of the biomass in the field, the biosorption of uranium by cross-linked and alginate calcium immobilized Saccharomyces cerevisiae is studied. Results indicate the maxium uptake is 185.2 mg/g by formaldehyde cross-linked biomass, and it is 769.2 mg/g by alginate calcium immobilized biomass. (authors)

Conversando com uma API: um estudo exploratório sobre TV social a partir da relação entre o twitter e a programação da televisão

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Márcio Carneiro dos Santos

2013-08-01

Full Text Available Discute-se o fenômeno do uso de redes sociais em paralelo ao consumo de TV, constituindo o que alguns autores  chamam de “backchannel”, um espaço secundário da produção de conteúdo e discussão sobre os programas que estão sendo assistidos de forma síncrona à sua emissão, formando o que propomos denominar aqui de nuvem de sentido. São exploradas as técnicas de mineração de dados através da ferramenta personalizada Social Tracker, desenvolvida na linguagem de programação Python, para coletar dados sobre o problema, considerando-se que, devido à grande quantidade de informações geradas neste ambiente, é cada vez mais difícil fazer isso manualmente.

Impact of mixed Torulaspora delbrueckii-Saccharomyces cerevisiae culture on high-sugar fermentation.

Science.gov (United States)

Bely, Marina; Stoeckle, Philippe; Masneuf-Pomarède, Isabelle; Dubourdieu, Denis

2008-03-20

Conventional wine yeasts produce high concentrations of volatile acidity, mainly acetic acid, during high-sugar fermentation. This alcoholic fermentation by-product is highly detrimental to wine quality and, in some cases, levels may even exceed legal limits. In this study, a non-conventional species, Torulaspora delbrueckii, was used, in pure cultures and mixed with Saccharomyces cerevisiae yeast, to ferment botrytized musts. Fermentation rate, biomass growth, and the formation of volatile acidity, acetaldehyde, and glycerol were considered. This study demonstrated that T. delbrueckii, often described as a low acetic producer under standard conditions, retained this quality even in a high-sugar medium. Unlike S. cerevisiae, this species did not respond to the hyper-osmotic medium by increasing acetic production as soon as it is inoculated into the must. Nevertheless, this yeast produced low ethanol and biomass yields, and the fermentation was sluggish. As a result, T. delbrueckii fermentations do not reach the required ethanol content (14%vol.), although this species can survive at this concentration. A mixed culture of T. delbrueckii and S. cerevisiae was the best combination for improving the analytical profile of sweet wine, particularly volatile acidity and acetaldehyde production. A mixed T. delbrueckii/S. cerevisiae culture at a 20:1 ratio produced 53% less in volatile acidity and 60% less acetaldehyde than a pure culture of S. cerevisiae. Inoculating S. cerevisiae after 5 days' fermentation by T. delbrueckii had less effect on volatile acidity and acetaldehyde production and resulted in stuck fermentation. These results contribute to a better understanding of the behaviour of non-Saccharomyces and their potential application in wine industry.

Engineering of carbon catabolite repression in recombinant xylose fermenting Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Roca, Christophe Francois Aime; Haack, Martin Brian; Olsson, Lisbeth

2004-01-01

analysed for changes in xylose consumption rate and ethanol production rate during anaerobic batch and chemostat cultivations on a mixture of 20 g l(-1) glucose and 50 g l(-1) xylose, and their characteristics were compared to the parental strain S. cerevisiae TMB3001 (XYL1, XYL2, XKS1). Improvement...... that xylose is a repressive sugar for S. cerevisiae....

Intracellular Ca2+ Regulation in Calcium Sensitive Phenotype of Saccharomyces cerevisiae

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HERMANSYAH

2010-03-01

Full Text Available Intracellular cytosolic Ca2+ concentration accumulation plays an essential information in Saccharomyces cerevisiae i.e. to explain cellular mechanism of Ca2+ sensitive phenotype. Disruption both S. cerevisiae PPase PTP2 and MSG5 genes showed an inhibited growth in the presence of Ca2+. On the other hand, by using Luminocounter with apoaequorin system, a method based upon luminescent photoprotein aequorin, intracellular Ca2+ concentration was accumulated as a consequence of calcium sensitive phenotype of S. cerevisiae. This fact indicated that PPase ptp2Δ and msg5Δ were involved in intracellular Ca2+ transport in addition their already known pathways i.e Mitogen Activated Protein Kinase cell wall integrity pathway, high osmolarity glycerol (HOG pathway, and pheromone response FUS3 pathway.

The adsorption of Sr(II) and Cs(I) ions by irradiated Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Yiming Tan; Jundong Feng; Liang Qiu; Zhentian Zhao; Xiaohong Zhang; Haiqian Zhang

2017-01-01

Adsorption behavior and mechanism of Sr(II) and Cs(I) in single and binary solutions using irradiated Saccharomyces cerevisiae was investigated. The effects of several environmental factors on Sr(II) and Cs(I) adsorption to irradiated Saccharomyces cerevisiae was determined. The equilibrium experimental data were simulated by different kinetic models and isotherm models. The combined effect of Sr(II) and Cs(I) on Saccharomyces cerevisiae is generally antagonistic. SEM and EDS analyses indicate that crystals formed on the cell surface are precipitate of Sr(II) and Cs(I), respectively. (author)

Conhecimento sobre fatores de risco para hipertensão arterial sistêmica por discentes do curso de enfermagem

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Ayla de Araujo Beserra

2017-03-01

Full Text Available Dentre as doenças crônicas não transmissíveis, a hipertensão arterial sistêmica (HAS é o maior problema de saúde social dos países desenvolvidos e em muitos dos emergentes. Nesse sentindo, objetivou-se identificar os fatores de risco dos discentes de enfermagem para o desenvolvimento da HAS em um centro de ensino superior de saúde na cidade de Arcoverde, Pernambuco. Trata-se de um estudo de caráter descritivo e exploratório com abordagem quantitativa. A amostra foi composta por 33 discentes, que cursavam o primeiro e o sexto período do curso superior de enfermagem. As variáveis estudadas foram: identificações, socioeconômicos e comportamentais. Em relação ao gênero, dos alunos consultados, apresentaram-se em maior porcentagem os do gênero feminino, informando que fazem uso de bebida alcoólica e apresentam hábitos saudáveis de alimentação. Evidenciou-se à inatividade física, sendo o fator mais citado dos riscos modificáveis, e os antecedentes familiares e a raça, fatores estes intrínsecos não modificáveis. Quanto ao nível de conhecimento sobre a HAS, nos dois períodos, é caracterizado como insuficiente sobre a doença hipertensiva. Torna-se necessário aprofundar alguns conhecimentos sobre HAS dos estudantes e a implementação de orientações sobre a prática de atividade física como um fator preventivo para HAS.

Sobre Escravidão no Império Romano (152 documentos epigráficos

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Glória Portal

1983-06-01

Full Text Available (primeiro parágrafo do artigo É verdade que crescem dia a dia a consciência e a sensibilidade quanto às formas de ultraje à pessoa humana, entre elas a escravidão. O interesse é cada vez maior por documentos e estudos esclarecedores da trajetória do escravismo, reveladores do aprofundamento, fortalecimento e nuanças deste sistema. As províncias romanas não conheceram na mesma amplitude a difusão do sistema escravista, o que implica em diferenças essenciais entre elas quanto aos modos de exploração.  Prosseguimos agora estudos iniciados há alguns anos sobre a escravidão numa região determinada do Império Romano: a Dácia.  Nosso objetivo é o de procurar, principalmente através de toda a série documental epigráfica existente sobre escravidão na Província Dácia de Trajano (152 documentos, discernir em que medida o sistema escravista penetrou nesta província e quais os tipos de relações de produção que estão se estabeleceram. Até aqui inexistia tradução portuguesa dos documentos mencionados acima; isto é um argumento forte a nos impulsionar no presente estudo; além de outras razões.

Induction of homologous recombination in Saccharomyces cerevisiae.

Science.gov (United States)

Simon, J R; Moore, P D

1988-09-01

We have investigated the effects of UV irradiation of Saccharomyces cerevisiae in order to distinguish whether UV-induced recombination results from the induction of enzymes required for homologous recombination, or the production of substrate sites for recombination containing regions of DNA damage. We utilized split-dose experiments to investigate the induction of proteins required for survival, gene conversion, and mutation in a diploid strain of S. cerevisiae. We demonstrate that inducing doses of UV irradiation followed by a 6 h period of incubation render the cells resistant to challenge doses of UV irradiation. The effects of inducing and challenge doses of UV irradiation upon interchromosomal gene conversion and mutation are strictly additive. Using the yeast URA3 gene cloned in non-replicating single- and double-stranded plasmid vectors that integrate into chromosomal genes upon transformation, we show that UV irradiation of haploid yeast cells and homologous plasmid DNA sequences each stimulate homologous recombination approximately two-fold, and that these effects are additive. Non-specific DNA damage has little effect on the stimulation of homologous recombination, as shown by studies in which UV-irradiated heterologous DNA was included in transformation/recombination experiments. We further demonstrate that the effect of competing single- and double-stranded heterologous DNA sequences differs in UV-irradiated and unirradiated cells, suggesting an induction of recombinational machinery in UV-irradiated S. cerevisiae cells.

Engineering and Evolution of Saccharomyces cerevisiae to Produce Biofuels and Chemicals.

Science.gov (United States)

Turner, Timothy L; Kim, Heejin; Kong, In Iok; Liu, Jing-Jing; Zhang, Guo-Chang; Jin, Yong-Su

To mitigate global climate change caused partly by the use of fossil fuels, the production of fuels and chemicals from renewable biomass has been attempted. The conversion of various sugars from renewable biomass into biofuels by engineered baker's yeast (Saccharomyces cerevisiae) is one major direction which has grown dramatically in recent years. As well as shifting away from fossil fuels, the production of commodity chemicals by engineered S. cerevisiae has also increased significantly. The traditional approaches of biochemical and metabolic engineering to develop economic bioconversion processes in laboratory and industrial settings have been accelerated by rapid advancements in the areas of yeast genomics, synthetic biology, and systems biology. Together, these innovations have resulted in rapid and efficient manipulation of S. cerevisiae to expand fermentable substrates and diversify value-added products. Here, we discuss recent and major advances in rational (relying on prior experimentally-derived knowledge) and combinatorial (relying on high-throughput screening and genomics) approaches to engineer S. cerevisiae for producing ethanol, butanol, 2,3-butanediol, fatty acid ethyl esters, isoprenoids, organic acids, rare sugars, antioxidants, and sugar alcohols from glucose, xylose, cellobiose, galactose, acetate, alginate, mannitol, arabinose, and lactose.

Fatty acid metabolism in Saccharomyces cerevisiae

NARCIS (Netherlands)

van Roermund, C. W. T.; Waterham, H. R.; IJlst, L.; Wanders, R. J. A.

2003-01-01

Peroxisomes are essential subcellular organelles involved in a variety of metabolic processes. Their importance is underlined by the identification of a large group of inherited diseases in humans in which one or more of the peroxisomal functions are impaired. The yeast Saccharomyces cerevisiae has

Microbially induced separation of quartz from calcite using Saccharomyces cerevisiae.

Science.gov (United States)

Padukone, S Usha; Natarajan, K A

2011-11-01

Cells of Saccharomyces cerevisiae and their metabolites were successfully utilized to achieve selective separation of quartz and calcite through microbially induced flotation and flocculation. S. cerevisiae was adapted to calcite and quartz minerals. Adsorption studies and electrokinetic investigations were carried out to understand the changes in the surface chemistry of yeast cells and the minerals after mutual interaction. Possible mechanisms in microbially induced flotation and flocculation are outlined. Copyright © 2011 Elsevier B.V. All rights reserved.

Repair of UV-damaged incoming plasmid DNA in Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Keszenman-Pereyra, David

1990-01-01

A whole-cell transformation assay was used for the repair of UV-damaged plasma DNA in highly-transformable haploid strains of Saccharomyces cerevisiae having different repair capabilities. The experiments described demonstrate that three epistasis groups (Friedberg 1988) are involved in the repair of UV-incoming DNA and that the repair processes act less efficiently on incoming DNA than they do on chromosomal DNA. The implications of these findings for UV repair in Saccharomyces cerevisiae are discussed. (author)

A Novel Saccharomyces cerevisiae Killer Strain Secreting the X Factor Related to Killer Activity and Inhibition of S. cerevisiae K1, K2 and K28 Killer Toxins.

Science.gov (United States)

Melvydas, Vytautas; Bružauskaitė, Ieva; Gedminienė, Genovaitė; Šiekštelė, Rimantas

2016-09-01

It was determined that Kx strains secrete an X factor which can inhibit all known Saccharomyces cerevisiae killer toxins (K1, K2, K28) and some toxins of other yeast species-the phenomenon not yet described in the scientific literature. It was shown that Kx type yeast strains posess a killer phenotype producing small but clear lysis zones not only on the sensitive strain α'1 but also on the lawn of S. cerevisiae K1, K2 and K28 type killer strains at temperatures between 20 and 30 °C. The pH at which killer/antikiller effect of Kx strain reaches its maximum is about 5.0-5.2. The Kx yeast were identified as to belong to S. cerevisiae species. Another newly identified S. cerevisiae killer strain N1 has killer activity but shows no antikilller properties against standard K1, K2 and K28 killer toxins. The genetic basis for Kx killer/antikiller phenotype was associated with the presence of M-dsRNA which is bigger than M-dsRNA of standard S. cerevisiae K1, K2, K28 type killer strains. Killer and antikiller features should be encoded by dsRNA. The phenomenon of antikiller (inhibition) properties was observed against some killer toxins of other yeast species. The molecular weight of newly identified killer toxins which produces Kx type strains might be about 45 kDa.

2μ plasmid in Saccharomyces species and in Saccharomyces cerevisiae.

Science.gov (United States)

Strope, Pooja K; Kozmin, Stanislav G; Skelly, Daniel A; Magwene, Paul M; Dietrich, Fred S; McCusker, John H

2015-12-01

We determined that extrachromosomal 2μ plasmid was present in 67 of the Saccharomyces cerevisiae 100-genome strains; in addition to variation in the size and copy number of 2μ, we identified three distinct classes of 2μ. We identified 2μ presence/absence and class associations with populations, clinical origin and nuclear genotypes. We also screened genome sequences of S. paradoxus, S. kudriavzevii, S. uvarum, S. eubayanus, S. mikatae, S. arboricolus and S. bayanus strains for both integrated and extrachromosomal 2μ. Similar to S. cerevisiae, we found no integrated 2μ sequences in any S. paradoxus strains. However, we identified part of 2μ integrated into the genomes of some S. uvarum, S. kudriavzevii, S. mikatae and S. bayanus strains, which were distinct from each other and from all extrachromosomal 2μ. We identified extrachromosomal 2μ in one S. paradoxus, one S. eubayanus, two S. bayanus and 13 S. uvarum strains. The extrachromosomal 2μ in S. paradoxus, S. eubayanus and S. cerevisiae were distinct from each other. In contrast, the extrachromosomal 2μ in S. bayanus and S. uvarum strains were identical with each other and with one of the three classes of S. cerevisiae 2μ, consistent with interspecific transfer. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Systems Biology of Saccharomyces cerevisiae Physiology and its DNA Damage Response

DEFF Research Database (Denmark)

Fazio, Alessandro

The yeast Saccharomyces cerevisiae is a model organism in biology, being widely used in fundamental research, the first eukaryotic organism to be fully sequenced and the platform for the development of many genomics techniques. Therefore, it is not surprising that S. cerevisiae has also been widely...... used in the field of systems biology during the last decade. This thesis investigates S. cerevisiae growth physiology and DNA damage response by using a systems biology approach. Elucidation of the relationship between growth rate and gene expression is important to understand the mechanisms regulating...... set of growth dependent genes by using a multi-factorial experimental design. Moreover, new insights into the metabolic response and transcriptional regulation of these genes have been provided by using systems biology tools (Chapter 3). One of the prerequisite of systems biology should...

Reflexões sobre a linguagem do ambiente chat no teletandem sob a perspectiva da natureza heterogênea da escrita

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Suzi Marques Spatti Cavalari

2012-07-01

Full Text Available O objetivo deste trabalho é discutir as características da linguagem mediada pelo computador em um ambiente de ensino e aprendizagem de língua estrangeira viabilizado pelo uso de recursos de comunicação síncrona na modalidade escrita – chat. O presente estudo se fundamenta em (i princípios teóricos sobre o uso de tecnologias e o ensino/aprendizagem de línguas estrangeiras no escopo do Projeto Teletandem Brasil: línguas estrangeiras para todos (TELLES, 2005; (ii estudos sobre as características da linguagem em interações via chat; (iii diferentes perspectivas teóricas a respeito das relações entre o oral e o escrito, enfatizando a perspectiva da heterogeneidade constitutiva da escrita (CORRÊA, 1997, 1998, 2001; e (iv em alguns conceitos pertinentes à área da Fonologia Prosódica (NESPOR; VOGEL, 1986. Toma‑se como material de análise a produção escrita de uma universitária brasileira (formanda em Licenciatura em Letras que interage com um universitário estadunidense (cursando Estudos Religiosos via Windows Live Messenger. Os dados foram coletados em um período de 5 meses, durante os quais os participantes interagiram via chat, totalizando 12 interações em inglês e em português. Na análise, enfocam-se as interações em língua portuguesa, particularmente a fragmentação das mensagens, o uso (ou não de sinais de pontuação e de abreviaturas na produção da participante brasileira, a fim de se discutirem as representações que ela constrói sobre a (sua escrita, sobre seu interlocutor, sobre si mesma e sobre o processo de ensino/aprendizagem de língua estrangeira.Palavras-chave: Língua escrita. Heterogeneidade. Chat. Teletandem.

Improved bread-baking process using Saccharomyces cerevisiae displayed with engineered cyclodextrin glucanotransferase.

Science.gov (United States)

Shim, Jae-Hoon; Seo, Nam-Seok; Roh, Sun-Ah; Kim, Jung-Wan; Cha, Hyunju; Park, Kwan-Hwa

2007-06-13

A bread-baking process was developed using a potential novel enzyme, cyclodextrin glucanotransferase[3-18] (CGTase[3-18]), that had previously been engineered to have enhanced hydrolyzing activity with little cyclodextrin (CD) formation activity toward starch. CGTase[3-18] was primarily manipulated to be displayed on the cell surface of Saccharomyces cerevisiae. S. cerevisiae carrying pdeltaCGT integrated into the chromosome exhibited starch-hydrolyzing activity at the same optimal pH and temperature as the free enzyme. Volumes of the bread loaves and rice cakes prepared using S. cerevisiae/pdeltaCGT increased by 20% and 45%, respectively, with no detectable CD. Retrogradation rates of the bread and rice cakes decreased significantly during storage. In comparison to the wild type, S. cerevisiae/pdeltaCGT showed improved viability during four freeze-thaw cycles. The results indicated that CGTase[3-18] displayed on the surface of yeast hydrolyzed starch to glucose and maltose that can be used more efficiently for yeast fermentation. Therefore, display of an antistaling enzyme on the cell surface of yeast has potential for enhancing the baking process.

Erlotinib: Um caso clínico de sucesso e algumas notas sobre a toxicidade hepática

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Agostinho Costa

2008-10-01

Full Text Available Resumo: Apresenta-se o caso clínico de uma mulher com adenocarcinoma do pulmão em que se conseguiu o controlo da doença, durante quinze meses, com erlotinib em segunda linha. Cerca de cinco meses após o início do tratamento ocorreu hiperbilirrubinemia isolada de grau 3, que motivou a redução da dose para 100 mg/dia. A este propósito, fazem-se alguns comentários sobre a toxicidade hepática do erlotinib e sobre o efeito das interacções farmacológicas no seu metabolismo.Rev Port Pneumol 2008; XIV (Supl 3: S29-S34 Abstract: A case of a woman with lung adenocarcinoma in which fifteen-month disease control was achieved with second-line erlotinib treatment is presented. Five months after treatment beginning, isolated grade 3 hyperbilirubinemia occurred and daily dose was reduced to 100 mg. Comments on erlotinib hepatic toxicity and the pharmacologic interactions on erlotinib metabolism are given.Rev Port Pneumol 2008; XIV (Supl 3: S29-S34 Palavras-chave: Erlotinib, toxicidade hepática, hiperbilirrubinemia, interacções farmacológicas, Key-words: Erlotinib, hepatic toxicity, hyperbilirubinemia, pharmacologic interactions

Molecular genetic diversity of the Saccharomyces yeasts in Taiwan: Saccharomyces arboricola, Saccharomyces cerevisiae and Saccharomyces kudriavzevii.

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Naumov, Gennadi I; Lee, Ching-Fu; Naumova, Elena S

2013-01-01

Genetic hybridization, sequence and karyotypic analyses of natural Saccharomyces yeasts isolated in different regions of Taiwan revealed three biological species: Saccharomyces arboricola, Saccharomyces cerevisiae and Saccharomyces kudriavzevii. Intraspecies variability of the D1/D2 and ITS1 rDNA sequences was detected among S. cerevisiae and S. kudriavzevii isolates. According to molecular and genetic analyses, the cosmopolitan species S. cerevisiae and S. kudriavzevii contain local divergent populations in Taiwan, Malaysia and Japan. Six of the seven known Saccharomyces species are documented in East Asia: S. arboricola, S. bayanus, S. cerevisiae, S. kudriavzevii, S. mikatae, and S. paradoxus.

Sucrose fermentation by Saccharomyces cerevisiae lacking hexose transport.

Science.gov (United States)

Batista, Anderson S; Miletti, Luiz C; Stambuk, Boris U

2004-01-01

Sucrose is the major carbon source used by Saccharomyces cerevisiae during production of baker's yeast, fuel ethanol and several distilled beverages. It is generally accepted that sucrose fermentation proceeds through extracellular hydrolysis of the sugar, mediated by the periplasmic invertase, producing glucose and fructose that are transported into the cells and metabolized. In the present work we analyzed the contribution to sucrose fermentation of a poorly characterized pathway of sucrose utilization by S. cerevisiae cells, the active transport of the sugar through the plasma membrane and its intracellular hydrolysis. A yeast strain that lacks the major hexose transporters (hxt1-hxt7 and gal2) is incapable of growing on or fermenting glucose or fructose. Our results show that this hxt-null strain is still able to ferment sucrose due to direct uptake of the sugar into the cells. Deletion of the AGT1 gene, which encodes a high-affinity sucrose-H(+) symporter, rendered cells incapable of sucrose fermentation. Since sucrose is not an inducer of the permease, expression of the AGT1 must be constitutive in order to allow growth of the hxt-null strain on sucrose. The molecular characterization of active sucrose transport and fermentation by S. cerevisiae cells opens new opportunities to optimize yeasts for sugarcane-based industrial processes.

Saccharomyces cerevisiae in the Production of Fermented Beverages

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Graeme M Walker

2016-11-01

Full Text Available Alcoholic beverages are produced following the fermentation of sugars by yeasts, mainly (but not exclusively strains of the species, Saccharomyces cerevisiae. The sugary starting materials may emanate from cereal starches (which require enzymatic pre-hydrolysis in the case of beers and whiskies, sucrose-rich plants (molasses or sugar juice from sugarcane in the case of rums, or from fruits (which do not require pre-hydrolysis in the case of wines and brandies. In the presence of sugars, together with other essential nutrients such as amino acids, minerals and vitamins, S. cerevisiae will conduct fermentative metabolism to ethanol and carbon dioxide (as the primary fermentation metabolites as the cells strive to make energy and regenerate the coenzyme NAD+ under anaerobic conditions. Yeasts will also produce numerous secondary metabolites which act as important beverage flavour congeners, including higher alcohols, esters, carbonyls and sulphur compounds. These are very important in dictating the final flavour and aroma characteristics of beverages such as beer and wine, but also in distilled beverages such as whisky, rum and brandy. Therefore, yeasts are of vital importance in providing the alcohol content and the sensory profiles of such beverages. This Introductory Chapter reviews, in general, the growth, physiology and metabolism of S. cerevisiae in alcoholic beverage fermentations.

Redox balancing in recombinant strains of Saccharomyces cerevisiae

Energy Technology Data Exchange (ETDEWEB)

Anderlund, M

1998-09-01

In metabolically engineered Saccharomyces cerevisiae expressing Pichia stipitis XYL1 and XYL2 genes, encoding xylose reductase (XR) and xylitol dehydrogenase (XDH), respectively, xylitol is excreted as the major product during anaerobic xylose fermentation and only low yields of ethanol are produced. This has been interpreted as a result of the dual cofactor dependence of XR and the exclusive use of NAD{sup +} by XDH. The excretion of xylitol was completely stopped and the formation of glycerol and acetic acid were reduced in xylose utilising S. cerevisiae strains cultivated in oxygen-limited conditions by expressing lower levels of XR than of XDH. The expression level of XYL1 and XYL2 were controlled by changing the promoters and transcription directions of the genes. A new functional metabolic pathway was established when Thermus thermophilus xylA gene was expressed in S. cerevisiae. The recombinant strain was able to ferment xylose to ethanol when cultivated on a minimal medium containing xylose as only carbon source. In order to create a channeled metabolic transfer in the two first steps of the xylose metabolism, XYL1 and XYL2 were fused in-frame and expressed in S. cerevisiae. When the fusion protein, containing a linker of three amino acids, was co expressed together with native XR and XDH monomers, enzyme complexes consisting of chimeric and native subunits were formed. The total activity of these complexes exhibited 10 and 9 times higher XR and XDH activity, respectively, than the original conjugates, consisting of only chimeric subunits. This strain produced less xylitol and the xylitol yield was lower than with strains only expressing native XR and XDH monomers. In addition, more ethanol and less acetic acid were formed. A new gene encoding the cytoplasmic transhydrogenase from Azotobacter vinelandii was cloned. The enzyme showed high similarity to the family of pyridine nucleotide-disulphide oxidoreductase. To analyse the physiological effect of

Bioethanol strains of Saccharomyces cerevisiae characterised by microsatellite and stress resistance

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Vanda Renata Reis

Full Text Available Abstract Strains of Saccharomyces cerevisiae may display characteristics that are typical of rough-type colonies, made up of cells clustered in pseudohyphal structures and comprised of daughter buds that do not separate from the mother cell post-mitosis. These strains are known to occur frequently in fermentation tanks with significant lower ethanol yield when compared to fermentations carried out by smooth strains of S. cerevisiae that are composed of dispersed cells. In an attempt to delineate genetic and phenotypic differences underlying the two phenotypes, this study analysed 10 microsatellite loci of 22 S. cerevisiae strains as well as stress resistance towards high concentrations of ethanol and glucose, low pH and cell sedimentation rates. The results obtained from the phenotypic tests by Principal-Component Analysis revealed that unlike the smooth colonies, the rough colonies of S. cerevisiae exhibit an enhanced resistance to stressful conditions resulting from the presence of excessive glucose and ethanol and high sedimentation rate. The microsatellite analysis was not successful to distinguish between the colony phenotypes as phenotypic assays. The relevant industrial strain PE-2 was observed in close genetic proximity to rough-colony although it does not display this colony morphology. A unique genetic pattern specific to a particular phenotype remains elusive.

A academia e participação social no Brasil: teses e dissertações sobre movimentos sociais produzidas na Unicamp e na Usp entre 1970 e 1995

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Samira Kauchakje

2002-01-01

Full Text Available Este artigo apresenta algumas reflexões suscitadas por uma pesquisa de doutoramento que versava sobre teses e dissertações acerca de movimentos sociais produzidas na USP e UNICAMP. A partir de alguns dados deste estudo, este artigo desenvolve-se tendo como pressuposto que há ligação entre interesse acadêmico e realidade socialThis article to present some meditation to one research of graduat about thesis and dissertation about social movement to make in USP and UNICAMP. To breack some consideration in that study, this article developing to support to have a alliance between academic interest and social reality.

Schizosaccharomyces pombe and Saccharomyces cerevisiae yeasts in sequential fermentations: Effect on phenolic acids of fermented Kei-apple (Dovyalis caffra L.) juice.

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Minnaar, P P; Jolly, N P; Paulsen, V; Du Plessis, H W; Van Der Rijst, M

2017-09-18

Kei-apple (Dovyalis caffra) is an evergreen tree indigenous to Southern Africa. The fruit contains high concentrations of l-malic acid, ascorbic acid, and phenolic acids. Kei-apple juice was sequentially inoculated with Schizosaccharomyces pombe and Saccharomyces cerevisiae yeasts. A reference fermentation using only S. cerevisiae was included. The fermentation was monitored by recording mass loss. At the end of fermentation, twelve untrained judges conducted free choice aroma profiling on the fruit wines. The Kei-apple juice and wines were analysed for total titratable acidity, total soluble solids, pH, alcohol, l-malic acid, and phenolic acids. Total titratable acidity was ca. 70% lower in Kei-apple wines produced with S. pombe+S. cerevisiae than in Kei-apple juice. Kei-apple wines produced with S. pombe+S. cerevisiae showed substantially lower concentrations of l-malic acid than Kei-apple wines produced with S. cerevisiae only. Wines produced with S. cerevisiae only proved higher in phenolic acid concentrations than wines produced with S. pombe+S. cerevisiae. Chlorogenic acid was the most abundant phenolic acid measured in the Kei-apple wines, followed by protocatechuic acid. Judges described the Kei-apple wines produced with S. pombe+S. cerevisiae as having noticeable off-odours, while wines produced with S. cerevisiae were described as fresh and fruity. Kei-apple wines (S. pombe+S. cerevisiae and S. cerevisiae) were of comparable vegetative and organic character. Saccharomyces cerevisiae produced Kei-apple wine with increased caffeic, chlorogenic, protocatechuic, and sinapic acids, whereas S. pombe+S. cerevisiae produced Kei-apple wines with increased ferulic, and p-coumaric acids and low l-malic acid. Copyright © 2017 Elsevier B.V. All rights reserved.

Acetylation dynamics and stoichiometry in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Weinert, Brian Tate; Iesmantavicius, Vytautas; Moustafa, Tarek

2014-01-01

Lysine acetylation is a frequently occurring posttranslational modification; however, little is known about the origin and regulation of most sites. Here we used quantitative mass spectrometry to analyze acetylation dynamics and stoichiometry in Saccharomyces cerevisiae. We found that acetylation...

Evaluation of cytochrome P-450 concentration in Saccharomyces cerevisiae strains

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Míriam Cristina Sakuragui Matuo

2010-09-01

Full Text Available Saccharomyces cerevisiae has been widely used in mutagenicity tests due to the presence of a cytochrome P-450 system, capable of metabolizing promutagens to active mutagens. There are a large number of S. cerevisiae strains with varying abilities to produce cytochrome P-450. However, strain selection and ideal cultivation conditions are not well defined. We compared cytochrome P-450 levels in four different S. cerevisiae strains and evaluated the cultivation conditions necessary to obtain the highest levels. The amount of cytochrome P-450 produced by each strain varied, as did the incubation time needed to reach the maximum level. The highest cytochrome P-450 concentrations were found in media containing fermentable sugars. The NCYC 240 strain produced the highest level of cytochrome P-450 when grown in the presence of 20 % (w/v glucose. The addition of ethanol to the media also increased cytochrome P-450 synthesis in this strain. These results indicate cultivation conditions must be specific and well-established for the strain selected in order to assure high cytochrome P-450 levels and reliable mutagenicity results.Linhagens de Saccharomyces cerevisiae tem sido amplamente empregadas em testes de mutagenicidade devido à presença de um sistema citocromo P-450 capaz de metabolizar substâncias pró-mutagênicas à sua forma ativa. Devido à grande variedade de linhagens de S. cerevisiae com diferentes capacidades de produção de citocromo P-450, torna-se necessária a seleção de cepas, bem como a definição das condições ideais de cultivo. Neste trabalho, foram comparados os níveis de citocromo P-450 em quatro diferentes linhagens de S. cerevisiae e avaliadas as condições de cultivo necessárias para obtenção de altas concentrações deste sistema enzimático. O maior nível enzimático foi encontrado na linhagem NCYC 240 em presença de 20 % de glicose (p/v. A adição de etanol ao meio de cultura também produziu um aumento na s

Anti-Saccharomyces cerevisiae and perinuclear anti-neutrophil cytoplasmic antibodies in coeliac disease before and after gluten-free diet.

Science.gov (United States)

Granito, A; Zauli, D; Muratori, P; Muratori, L; Grassi, A; Bortolotti, R; Petrolini, N; Veronesi, L; Gionchetti, P; Bianchi, F B; Volta, U

2005-04-01

Anti-Saccharomyces cerevisiae and perinuclear anti-neutrophil cytoplasmic autoantibodies are markers of Crohn's disease and ulcerative colitis respectively. To determine the prevalence of anti-S. cerevisiae and perinuclear anti-neutrophil cytoplasmic autoantibodies in a large series of coeliac disease patients before and after gluten free diet, and to correlate anti-S. cerevisiae-positivity with intestinal mucosal damage. One hundred and five consecutive coeliac disease patients and 141 controls (22 ulcerative colitis, 24 Crohn's disease, 30 primary sclerosing cholangitis, 15 postenteritis syndrome, 50 blood donors) were tested for anti-S. cerevisiae by enzyme-linked immunosorbent assay and for perinuclear anti-neutrophil cytoplasmic autoantibodies by indirect immunofluorescence. In coeliac disease anti-S. cerevisiae (immunoglobulin G and/or immunoglobulin A) were slightly less frequent (59%) than in Crohn's disease (75%, P = 0.16) and significantly more frequent than in ulcerative colitis (27%), primary sclerosing cholangitis (30%), postenteritis syndrome (26%) and blood donors (4%) (P = 0.009, P = 0.0002, P = 0.025, P < 0.0001). No correlation was found between anti-S. cerevisiae and degree of mucosal damage. Perinuclear anti-neutrophil cytoplasmic autoantibodies were detected only in one coeliac. After gluten free diet the disappearance of anti-S. cerevisiae-immunoglobulin A (93%) was more frequent than that of immunoglobulin G (17%, P = 0.0001); perinuclear anti-neutrophil cytoplasmic autoantibodies disappeared in the only coeliac positive at diagnosis. More than half of untreated coeliacs are anti-S. cerevisiae-positive irrespective of the severity of mucosal damage. Differently from immunoglobulin A, anti-S. cerevisiae-immunoglobulin G persisted in more than 80% after gluten free diet. The high prevalence of anti-S. cerevisiae in coeliac disease suggests that they may be the effect of a non-specific immune response in course of chronic small bowel disease.

Signature pathway expression of xylose utilization in the genetically engineered industrial yeast Saccharomyces cerevisiae

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Background: The limited xylose utilizing ability of native Saccharomyces cerevisiae has been a major obstacle for efficient cellulosic ethanol production from lignocellulosic materials. Haploid laboratory strains of S. cerevisiae are commonly used for genetic engineering to enable its xylose utiliza...

Avaliação do conhecimento de médicos não radiologistas sobre aspectos relacionados à radiação ionizante em exames de imagem

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Renata Rodrigues Madrigano

2014-08-01

Full Text Available Objetivo:Avaliar o conhecimento dos médicos não radiologistas sobre a utilização da radiação ionizante em exames de imagem.Materiais e Métodos:Estudo transversal, utilizando questionário anônimo, aplicado a médicos de especialidades clínicas e cirúrgicas, dividido em duas partes: uma com questões sobre as características dos médicos, frequência de solicitação de exames e de participação em eventos de atualização profissional, e outra com questões de múltipla escolha, abordando conhecimentos gerais sobre radiação, princípios de otimização e radioproteção.Resultados:De 309 questionários distribuídos, 120 (38,8% foram respondidos, 50% por médicos de especialidades cirúrgicas e 50% clínicas; 45% e 2,5% dos médicos responderam, respectivamente, que a ressonância magnética e a ultrassonografia utilizam radiação ionizante. No geral, a média das notas foi maior nas especialidades cirúrgicas, sem diferenças significativas, exceto na questão sobre exposição em grávidas (p = 0,047. Os médicos que se atualizam profissionalmente mostraram conhecimento sobre radiação ionizante estatisticamente superior aos demais, principalmente os que frequentam reuniões clínicas (p = 0,050 e participam de atividades de ensino (p = 0,047.Conclusão:O conhecimento dos médicos não radiologistas sobre radiação ionizante é heterogêneo e em alguns pontos precisa ser melhorado. Reuniões clínicas multidisciplinares e atividades de ensino são importantes formas de disseminar informações sobre o tema.

Switching the mode of sucrose utilization by Saccharomyces cerevisiae

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Miletti Luiz C

2008-02-01

Full Text Available Abstract Background Overflow metabolism is an undesirable characteristic of aerobic cultures of Saccharomyces cerevisiae during biomass-directed processes. It results from elevated sugar consumption rates that cause a high substrate conversion to ethanol and other bi-products, severely affecting cell physiology, bioprocess performance, and biomass yields. Fed-batch culture, where sucrose consumption rates are controlled by the external addition of sugar aiming at its low concentrations in the fermentor, is the classical bioprocessing alternative to prevent sugar fermentation by yeasts. However, fed-batch fermentations present drawbacks that could be overcome by simpler batch cultures at relatively high (e.g. 20 g/L initial sugar concentrations. In this study, a S. cerevisiae strain lacking invertase activity was engineered to transport sucrose into the cells through a low-affinity and low-capacity sucrose-H+ symport activity, and the growth kinetics and biomass yields on sucrose analyzed using simple batch cultures. Results We have deleted from the genome of a S. cerevisiae strain lacking invertase the high-affinity sucrose-H+ symporter encoded by the AGT1 gene. This strain could still grow efficiently on sucrose due to a low-affinity and low-capacity sucrose-H+ symport activity mediated by the MALx1 maltose permeases, and its further intracellular hydrolysis by cytoplasmic maltases. Although sucrose consumption by this engineered yeast strain was slower than with the parental yeast strain, the cells grew efficiently on sucrose due to an increased respiration of the carbon source. Consequently, this engineered yeast strain produced less ethanol and 1.5 to 2 times more biomass when cultivated in simple batch mode using 20 g/L sucrose as the carbon source. Conclusion Higher cell densities during batch cultures on 20 g/L sucrose were achieved by using a S. cerevisiae strain engineered in the sucrose uptake system. Such result was accomplished by

Switching the mode of sucrose utilization by Saccharomyces cerevisiae.

Science.gov (United States)

Badotti, Fernanda; Dário, Marcelo G; Alves, Sergio L; Cordioli, Maria Luiza A; Miletti, Luiz C; de Araujo, Pedro S; Stambuk, Boris U

2008-02-27

Overflow metabolism is an undesirable characteristic of aerobic cultures of Saccharomyces cerevisiae during biomass-directed processes. It results from elevated sugar consumption rates that cause a high substrate conversion to ethanol and other bi-products, severely affecting cell physiology, bioprocess performance, and biomass yields. Fed-batch culture, where sucrose consumption rates are controlled by the external addition of sugar aiming at its low concentrations in the fermentor, is the classical bioprocessing alternative to prevent sugar fermentation by yeasts. However, fed-batch fermentations present drawbacks that could be overcome by simpler batch cultures at relatively high (e.g. 20 g/L) initial sugar concentrations. In this study, a S. cerevisiae strain lacking invertase activity was engineered to transport sucrose into the cells through a low-affinity and low-capacity sucrose-H+ symport activity, and the growth kinetics and biomass yields on sucrose analyzed using simple batch cultures. We have deleted from the genome of a S. cerevisiae strain lacking invertase the high-affinity sucrose-H+ symporter encoded by the AGT1 gene. This strain could still grow efficiently on sucrose due to a low-affinity and low-capacity sucrose-H+ symport activity mediated by the MALx1 maltose permeases, and its further intracellular hydrolysis by cytoplasmic maltases. Although sucrose consumption by this engineered yeast strain was slower than with the parental yeast strain, the cells grew efficiently on sucrose due to an increased respiration of the carbon source. Consequently, this engineered yeast strain produced less ethanol and 1.5 to 2 times more biomass when cultivated in simple batch mode using 20 g/L sucrose as the carbon source. Higher cell densities during batch cultures on 20 g/L sucrose were achieved by using a S. cerevisiae strain engineered in the sucrose uptake system. Such result was accomplished by effectively reducing sucrose uptake by the yeast cells

REFLETIR SOBRE O ENSINO DA ÉTICA NA GRADUAÇÃO DE ENFERMEIROS, EM PORTUGAL

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Ana Reis

2013-12-01

Full Text Available Existem em Portugal alguns estudos sobre o ensino da ética na área dos profissionais de saúde. As teorias a divulgar no curriculum relativo à Ética, Deontologia e Bioética em Enfermagem deverão estar diretamente articuladas com os filósofos, ou outros especialistas, nos quais se inspiraram. Sendo uma das principais finalidades do ensino, em Enfermagem, a preparação dos estudantes para um mundo marcado por complexos dilemas éticos, suscitados pela atividade científica e tecnológica, propomos, por um lado, um ensino em ética que siga as orientações preconizadas no documento Recomendações Relativas ao Ensino da Ética e Deontologia no Curso de Enfermagem (editado pela Ordem dos Enfermeiros e, por outro lado, o desenvolvimento da ética associado à moral, de modo a proporcionar um equilíbrio entre princípios éticos e as regras institucionais, remetendo diretamente para a deontologia.

LEITURA DIGITAL E COMPLEXIFICAÇÃO: REFLEXÕES SOBRE A CONSTITUIÇÃO DE SI

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Nize Maria Campos Pellanda

2009-08-01

Full Text Available Este artigo trata da leitura abordada com ênfase no espaço digital e sustentada nos pressupostos do paradigma da complexidade. O texto inicia com uma caracterização breve da nova cultura digital e suas possibilidades em termos de uma potencialização das condições de construção do sujeito/ construção de subjetividade. A cibercultura torna-se possível a partir de uma abordagem complexa da realidade, ou seja, da consideração de diferentes dimensões dos fenômenos de forma integrada. Nesse sentido, a leitura é considera como uma ação complexa por não separar cognição da constituição de si, no processo de ler. Alguns dados de pesquisa sobre leitura com adolescentes de classes populares são trazidos para ilustrar os elementos teóricos discutidos.

On the origins and industrial applications of Saccharomyces cerevisiae × Saccharomyces kudriavzevii hybrids.

Science.gov (United States)

Peris, David; Pérez-Torrado, Roberto; Hittinger, Chris Todd; Barrio, Eladio; Querol, Amparo

2018-01-01

Companies based on alcoholic fermentation products, such as wine, beer and biofuels, use yeasts to make their products. Each industrial process utilizes different media conditions, which differ in sugar content, the presence of inhibitors and fermentation temperature. Saccharomyces cerevisiae has traditionally been the main yeast responsible for most fermentation processes. However, the market is changing due to consumer demand and external factors such as climate change. Some processes, such as biofuel production or winemaking, require new yeasts to solve specific challenges, especially those associated with sustainability, novel flavours and altered alcohol content. One of the proposed solutions is the application of yeast hybrids. The lager beer market has been dominated by S. cerevisiae × S. eubayanus hybrids. However, several less thoroughly studied hybrids have been isolated from other diverse industrial processes. Here we focus on S. cerevisiae × S. kudriavzevii hybrids, which have been isolated from diverse industrial conditions that include wine, ale beer, cider and dietary supplements. Emerging data suggest an extended and complex story of adaptation of these hybrids to traditional industrial conditions. S. cerevisiae × S. kudriavzevii hybrids are also being explored for new industrial applications, such as biofuels. This review describes the past, present and future of S. cerevisiae × S. kudriavzevii hybrids. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Nitrogen Catabolite Repression in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Hofman-Bang, H Jacob Peider

1999-01-01

In Saccharomyces cerevisiae the expression of all known nitrogen catabolite pathways are regulated by four regulators known as Gln3, Gat1, Da180, and Deh1. This is known as nitrogen catabolite repression (NCR). They bind to motifs in the promoter region to the consensus sequence S' GATAA 3'. Gln3...

[Molecular evolution of the sulphite efflux gene SSU1 in Saccharomyces cerevisiae].

Science.gov (United States)

Peng, Li-Xin; Sun, Fei-Fei; Huang, Yan-Yan; Li, Zhen-Chong

2013-11-01

The SSU1 gene encoding a membrane sulfite pump is a main facilitator invovled in sulfite efflux. In Saccharomyce cerevisiae, various range of resistance to sulfite was observed among strains. To explore the evolution traits of SSU1 gene, the population data of S. cerevisiae were collected and analyzed. The phylogenetic analysis indicated that S. cerevisiae population can be classified into three sub-populations, and the positive selection was detected in population by McDonald-Kreitman test. The anaylsis of Ka/Ks ratios further showed that S. cerevisiae sub-population was undergoing positive selection. This finding was also supported by PAML branch model. Nine potential positive selection sites were predicted by branch-site model, and four sites exclusively belong to the sub-population under positive seletion. The data from ssulp protein structure demonstrated that three sites are substitutions between polar and hydrophobic amino acids, and only one site of substitutaion from basic amino acid to basic amino acid (345R/K). Because amino acid pKa values are crucial for sulfite pump to maintain their routine function, positive selection of these amino acid substitutions might affect sulfite efflux efficient.

Stress Tolerance Variations in Saccharomyces cerevisiae Strains from Diverse Ecological Sources and Geographical Locations.

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Yan-Lin Zheng

Full Text Available The budding yeast Saccharomyces cerevisiae is a platform organism for bioethanol production from various feedstocks and robust strains are desirable for efficient fermentation because yeast cells inevitably encounter stressors during the process. Recently, diverse S. cerevisiae lineages were identified, which provided novel resources for understanding stress tolerance variations and related shaping factors in the yeast. This study characterized the tolerance of diverse S. cerevisiae strains to the stressors of high ethanol concentrations, temperature shocks, and osmotic stress. The results showed that the isolates from human-associated environments overall presented a higher level of stress tolerance compared with those from forests spared anthropogenic influences. Statistical analyses indicated that the variations of stress tolerance were significantly correlated with both ecological sources and geographical locations of the strains. This study provides guidelines for selection of robust S. cerevisiae strains for bioethanol production from nature.

PRODUCTION, PROPERTIES AND APPLICATION OF SACCHAROMYCES CEREVISIAE VGSH-2 INULINASE

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G. P. Shuvaeva

2014-01-01

Full Text Available Summary. Experimental data on an acid and thermal inactivation of a high refined inulinase (2,1-β-D- fructanfructanohydrolase, KF 3.2.17, produced by the race of Saccharomyces cerevisiae VGSh-2 yeast are presented. The strain of S. cerevisiae VGSh-2 was produced by the method of the induced mutagenesis and deposited to the collection of pure cultures of the chair of biochemistry and biotechnology of Voronezh state university of engineering technologies. The cells of source culture (S. cerevisiae XII were affected step-by-step by the ultra-violet radiation (UFR and UFR in a complex with a chemical mutagen (etilenimine. The culture was grown up by the method of liquid-phase deep cultivation on a constant nutrient medium. Refining conditions for inulinase are sorted out. Activity of enzyme dependence on physical and chemical factors (рН and temperature is obtained and numerical values of the main kinetic constants – Km and Vmax are determined. The structure of enzyme molecule is studied by an infrared-spectroscopy method: the type and relative quantity of elements of secondary structure of protein are defined. Substrate binding groups of the active center of an inulinase are found. The comparative analysis of the ability to hydrolysis of inulin in several enzyme preparations from Jerusalem artichoke and to the subsequent their fermentation by the VGSh-2 and XI S. cerevisiae yeasts is carried out. Optimum conditions of enzyme hydrolysis of inulin are selected. Research of the fermentation process of starchcontaining raw materials by yeasts of VGSh-2 and XI races is done. It is established that the using of VGSh-2 S. cerevisiae yeast for a grain wort and the Jerusalem artichoke fermentation, allows to increase an extraction of ethyl alcohol comparing to control race, to improve its quality characteristics, and also allows to predict the using of new race in the food industry for production ethanol from grain raw materials and a fermentation of

Industrial Systems Biology of Saccharomyces cerevisiae Enables Novel Succinic Acid Cell Factory

DEFF Research Database (Denmark)

Otero, José Manuel; Cimini, Donatella; Patil, Kiran Raosaheb

2013-01-01

Saccharomyces cerevisiae is the most well characterized eukaryote, the preferred microbial cell factory for the largest industrial biotechnology product (bioethanol), and a robust commerically compatible scaffold to be exploitted for diverse chemical production. Succinic acid is a highly sought......-direction of carbon fluxes in S. cerevisiae, and hence show proof of concept that this is a potentially attractive cell factory for over-producing different platform chemicals....

Growth of non-Saccharomyces yeasts affects nutrient availability for Saccharomyces cerevisiae during wine fermentation.

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Medina, Karina; Boido, Eduardo; Dellacassa, Eduardo; Carrau, Francisco

2012-07-02

Yeast produces numerous secondary metabolites during fermentation that impact final wine quality. Although it is widely recognized that growth of diverse non-Saccharomyces (NS) yeast can positively affect flavor complexity during Saccharomyces cerevisiae wine fermentation, the inability to control spontaneous or co-fermentation processes by NS yeast has restricted their use in winemaking. We selected two NS yeasts from our Uruguayan native collection to study NS-S. cerevisiae interactions during wine fermentation. The selected strains of Hanseniaspora vineae and Metschnikowia pulcherrima had different yeast assimilable nitrogen consumption profiles and had different effects on S. cerevisiae fermentation and growth kinetics. Studies in which we varied inoculum size and using either simultaneous or sequential inoculation of NS yeast and S. cerevisiae suggested that competition for nutrients had a significant effect on fermentation kinetics. Sluggish fermentations were more pronounced when S. cerevisiae was inoculated 24h after the initial stage of fermentation with a NS strain compared to co-inoculation. Monitoring strain populations using differential WL nutrient agar medium and fermentation kinetics of mixed cultures allowed for a better understanding of strain interactions and nutrient addition effects. Limitation of nutrient availability for S. cerevisiae was shown to result in stuck fermentations as well as to reduce sensory desirability of the resulting wine. Addition of diammonium phosphate (DAP) and a vitamin mix to a defined medium allowed for a comparison of nutrient competition between strains. Addition of DAP and the vitamin mix was most effective in preventing stuck fermentations. Copyright © 2012 Elsevier B.V. All rights reserved.

Development of Efficient Xylose Fermentation in Saccharomyces cerevisiae : Xylose Isomerase as a Key Component

NARCIS (Netherlands)

Van Maris, A.J.A.; Winkler, A.A.; Kuyper, M.; De Laat, W.T.; Van Dijken, J.P.; Pronk, J.T.

2007-01-01

Metabolic engineering of Saccharomyces cerevisiae for ethanol production from d-xylose, an abundant sugar in plant biomass hydrolysates, has been pursued vigorously for the past 15 years. Whereas wild-type S. cerevisiae cannot ferment d-xylose, the ketoisomer d-xylulose can be metabolised slowly.

Invertase SUC2 Is the Key Hydrolase for Inulin Degradation in Saccharomyces cerevisiae

OpenAIRE

Wang, Shi-An; Li, Fu-Li

2013-01-01

Specific Saccharomyces cerevisiae strains were recently found to be capable of efficiently utilizing inulin, but genetic mechanisms of inulin hydrolysis in yeast remain unknown. Here we report functional characteristics of invertase SUC2 from strain JZ1C and demonstrate that SUC2 is the key enzyme responsible for inulin metabolism in S. cerevisiae.

Saccharomyces cerevisiae in the Production of Whisk(ey

Directory of Open Access Journals (Sweden)

Graeme M. Walker

2016-12-01

Full Text Available Whisk(ey is a major global distilled spirit beverage. Whiskies are produced from cereal starches that are saccharified, fermented and distilled prior to spirit maturation. The strain of Saccharomyces cerevisiae employed in whisky fermentations is crucially important not only in terms of ethanol yields, but also for production of minor yeast metabolites which collectively contribute to development of spirit flavour and aroma characteristics. Distillers must therefore pay very careful attention to the strain of yeast exploited to ensure consistency of fermentation performance and spirit congener profiles. In the Scotch whisky industry, initiatives to address sustainability issues facing the industry (for example, reduced energy and water usage have resulted in a growing awareness regarding criteria for selecting new distilling yeasts with improved efficiency. For example, there is now a desire for Scotch whisky distilling yeasts to perform under more challenging conditions such as high gravity wort fermentations. This article highlights the important roles of S. cerevisiae strains in whisky production (with particular emphasis on Scotch and describes key fermentation performance attributes sought in distiller’s yeast, such as high alcohol yields, stress tolerance and desirable congener profiles. We hope that the information herein will be useful for whisky producers and yeast suppliers in selecting new distilling strains of S. cerevisiae, and for the scientific community to stimulate further research in this area.

Ethanol production from xylose in engineered Saccharomyces cerevisiae strains. Current state and perspectives

Energy Technology Data Exchange (ETDEWEB)

Matsushika, Akinori; Inoue, Hiroyuki; Sawayama, Shigeki [National Inst. of Advanced Industrial Science and Technology (AIST), Hiroshima (JP). Biomass Technology Research Center (BTRC); Kodaki, Tsutomu [Kyoto Univ. (Japan). Inst. of Advanced Energy

2009-08-15

Bioethanol production from xylose is important for utilization of lignocellulosic biomass as raw materials. The research on yeast conversion of xylose to ethanol has been intensively studied especially for genetically engineered Saccharomyces cerevisiae during the last 20 years. S. cerevisiae, which is a very safe microorganism that plays a traditional and major role in industrial bioethanol production, has several advantages due to its high ethanol productivity, as well as its high ethanol and inhibitor tolerance. However, this yeast cannot ferment xylose, which is the dominant pentose sugar in hydrolysates of lignocellulosic biomass. A number of different strategies have been applied to engineer yeasts capable of efficiently producing ethanol from xylose, including the introduction of initial xylose metabolism and xylose transport, changing the intracellular redox balance, and overexpression of xylulokinase and pentose phosphate pathways. In this review, recent progress with regard to these studies is discussed, focusing particularly on xylose-fermenting strains of S. cerevisiae. Recent studies using several promising approaches such as host strain selection and adaptation to obtain further improved xylose-utilizing S. cerevisiae are also addressed. (orig.)

Advances in metabolic engineering of yeast Saccharomyces cerevisiae for production of chemicals

DEFF Research Database (Denmark)

Borodina, Irina; Nielsen, Jens

2014-01-01

Yeast Saccharomyces cerevisiae is an important industrial host for production of enzymes, pharmaceutical and nutraceutical ingredients and recently also commodity chemicals and biofuels. Here, we review the advances in modeling and synthetic biology tools and how these tools can speed up the deve......Yeast Saccharomyces cerevisiae is an important industrial host for production of enzymes, pharmaceutical and nutraceutical ingredients and recently also commodity chemicals and biofuels. Here, we review the advances in modeling and synthetic biology tools and how these tools can speed up...... the development of yeast cell factories. We also present an overview of metabolic engineering strategies for developing yeast strains for production of polymer monomers: lactic, succinic, and cis,cis-muconic acids. S. cerevisiae has already firmly established itself as a cell factory in industrial biotechnology...

Bioethanol strains of Saccharomyces cerevisiae characterised by microsatellite and stress resistance.

Science.gov (United States)

Reis, Vanda Renata; Antonangelo, Ana Teresa Burlamaqui Faraco; Bassi, Ana Paula Guarnieri; Colombi, Débora; Ceccato-Antonini, Sandra Regina

Strains of Saccharomyces cerevisiae may display characteristics that are typical of rough-type colonies, made up of cells clustered in pseudohyphal structures and comprised of daughter buds that do not separate from the mother cell post-mitosis. These strains are known to occur frequently in fermentation tanks with significant lower ethanol yield when compared to fermentations carried out by smooth strains of S. cerevisiae that are composed of dispersed cells. In an attempt to delineate genetic and phenotypic differences underlying the two phenotypes, this study analysed 10 microsatellite loci of 22 S. cerevisiae strains as well as stress resistance towards high concentrations of ethanol and glucose, low pH and cell sedimentation rates. The results obtained from the phenotypic tests by Principal-Component Analysis revealed that unlike the smooth colonies, the rough colonies of S. cerevisiae exhibit an enhanced resistance to stressful conditions resulting from the presence of excessive glucose and ethanol and high sedimentation rate. The microsatellite analysis was not successful to distinguish between the colony phenotypes as phenotypic assays. The relevant industrial strain PE-2 was observed in close genetic proximity to rough-colony although it does not display this colony morphology. A unique genetic pattern specific to a particular phenotype remains elusive. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Functional relevance of water and glycerol channels in Saccharomyces cerevisiae.

Science.gov (United States)

Sabir, Farzana; Loureiro-Dias, Maria C; Soveral, Graça; Prista, Catarina

2017-05-01

Our understanding of the functional relevance of orthodox aquaporins and aquaglyceroporins in Saccharomyces cerevisiae is essentially based on phenotypic variations obtained by expression/overexpression/deletion of these major intrinsic proteins in selected strains. These water/glycerol channels are considered crucial during various life-cycle phases, such as sporulation and mating and in some life processes such as rapid freeze-thaw tolerance, osmoregulation and phenomena associated with cell surface. Despite their putative functional roles not only as channels but also as sensors, their underlying mechanisms and their regulation are still poorly understood. In the present review, we summarize and discuss the physiological relevance of S. cerevisiae aquaporins (Aqy1 and Aqy2) and aquaglyceroporins (Fps1 and Yfl054c). In particular, the fact that most S. cerevisiae laboratory strains harbor genes coding for non-functional aquaporins, while wild and industrial strains possess at least one functional aquaporin, suggests that aquaporin activity is required for cell survival under more harsh conditions. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Early manifestations of replicative aging in the yeast Saccharomyces cerevisiae

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Maksim I. Sorokin

2014-01-01

Full Text Available The yeast Saccharomyces cerevisiae is successfully used as a model organism to find genes responsible for lifespan control of higher organisms. As functional decline of higher eukaryotes can start as early as one quarter of the average lifespan, we asked whether S. cerevisiae can be used to model this manifestation of aging. While the average replicative lifespan of S. cerevisiae mother cells ranges between 15 and 30 division cycles, we found that resistances to certain stresses start to decrease much earlier. Looking into the mechanism, we found that knockouts of genes responsible for mitochondriato-nucleus (retrograde signaling, RTG1 or RTG3, significantly decrease the resistance of cells that generated more than four daughters, but not of the younger ones. We also found that even young mother cells frequently contain mitochondria with heterogeneous transmembrane potential and that the percentage of such cells correlates with replicative age. Together, these facts suggest that retrograde signaling starts to malfunction in relatively young cells, leading to accumulation of heterogeneous mitochondria within one cell. The latter may further contribute to a decline in stress resistances.

Nem só de debates epistemológicos vive o pesquisador em administração: alguns apontamentos sobre disputas entre paradigmas e campo científico

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Milka Alves Correia Barbosa

Full Text Available A discussão sobre abordagens paradigmáticas no campo da Administração pode ser profícua quando provoca os pesquisadores a refletir sobre premissas, práticas e valores compartilhados por uma comunidade científica. Entretanto, ao extremo, torna-se uma disputa que impede a busca de outras abordagens para lidar com a complexidade dos fenômenos sociais. Nesse sentido, importa compreender que, na produção do conhecimento científico, os pesquisadores não se deparam somente com escolhas acerca de epistemologia, de lógica ou de teoria linguística, mas, também, com problemas de política. Este ensaio objetiva contribuir com reflexões sobre o pesquisador e os desafios epistemológicos e políticos com os quais se depara no fazer pesquisa, argumentando que não se trata somente de uma escolha entre positivismos e interpretativismos, mas igualmente envolve disputas de poder dentro de um campo científico. Para tanto, foram selecionados intencionalmente textos com conceitos-chave, como paradigmas e campo científico. Em resposta ao objetivo geral deste ensaio, consideramos que o fazer ciência constitui uma atividade humana que possui vínculo indissociável com espaço e tempo e imbrica-se com jogos de poder. Entendemos, ainda, que o campo científico da Administração no Brasil é um espaço de competitividade e lutas políticas do qual fazemos parte, quer seja como opressores ou privilegiados, mas nunca como meros expectadores. Nessa arena, nem só de debates epistemológicos vive o pesquisador em Administração.

Physiological impact and context dependency of transcriptional responses : A chemostat study in Saccharomyces cerevisiae

NARCIS (Netherlands)

Tai, S.L.

2007-01-01

This thesis is a compilation of a four-year PhD project on bakers' yeast (Saccharomyces cerevisiae). Since the entire S. cerevisiae genome sequence became available in 1996, DNA-microarray analysis has become a popular high-information-density tool for analyzing gene expression in this important

Performance evaluation of Pichia kluyveri, Kluyveromyces marxianus and Saccharomyces cerevisiae in industrial tequila fermentation.

Science.gov (United States)

Amaya-Delgado, L; Herrera-López, E J; Arrizon, Javier; Arellano-Plaza, M; Gschaedler, A

2013-05-01

Traditionally, industrial tequila production has used spontaneous fermentation or Saccharomyces cerevisiae yeast strains. Despite the potential of non-Saccharomyces strains for alcoholic fermentation, few studies have been performed at industrial level with these yeasts. Therefore, in this work, Agave tequilana juice was fermented at an industrial level using two non-Saccharomyces yeasts (Pichia kluyveri and Kluyveromyces marxianus) with fermentation efficiency higher than 85 %. Pichia kluyveri (GRO3) was more efficient for alcohol and ethyl lactate production than S. cerevisiae (AR5), while Kluyveromyces marxianus (GRO6) produced more isobutanol and ethyl-acetate than S. cerevisiae (AR5). The level of volatile compounds at the end of fermentation was compared with the tequila standard regulation. All volatile compounds were within the allowed range except for methanol, which was higher for S. cerevisiae (AR5) and K. marxianus (GRO6). The variations in methanol may have been caused by the Agave tequilana used for the tests, since this compound is not synthesized by these yeasts.

Efeito do manejo pré-abate sobre alguns parâmetros fisiológicos em fêmeas suínas pesadas Effect of pre-slaughter management on physiological parameters of heavy-weight female pigs

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Osmar Antonio Dalla Costa

2009-06-01

Full Text Available O objetivo neste trabalho foi avaliar o efeito do período de descanso (3, 5, 7 e 9 horas dos suínos no frigorífico (PDF e da localização dos suínos na carroceria do caminhão (PBO, quando transportados, no inverno ou verão, sobre alguns parâmetros fisiológicos avaliados em 64 fêmeas, com peso médio de 130kg para abate, durante o manejo pré-abate. Para a análise estatística, foram considerados, no modelo de análise da variância, os efeitos de bloco, PDF, PBO e da interação (bloco x PDF, entre outros. O PDF influenciou, significativamente, as concentrações de lactato no sangue e cortisol na saliva. Suínos que descansaram 5 e 7 horas apresentaram maior concentração de lactato em relação aos animais que descansaram 3 e 9 horas. No transporte, a freqüência cardíaca foi muito maior em relação aos demais locais avaliados. Concluiu-se que o incremento do PDF não promove mudanças na freqüência cardíaca, nas concentrações de glicose e CPK no sangue e cortisol na saliva, mas interfere na concentração de lactato no sangue dos suínos.The aim of the research was to evaluate the effect of pig lairage time (PDF=3, 5, 7 and 9 hours and evaluate the effect of pig position into the truck (PBO during transportation to slaughterhouse, in winter or summer conditions, on some physiologic parameters evaluated on 64 heavyweight females with mean liveweight of 130kg during pre-slaughter events. The following effects were considered in the statistical analysis of variance model: block (BL=summer farm or winter farm, PDF, PBO and interaction (Block x PDF, under other factors. The PDF influenced significativelly blood lactate and saliva cortisol levels. Pig submitted to 5 and 7 hours of lairage had higher levels of lactate when compared to pigs submitted to 3 and 9 hours of lairage. During transport the heart rate were higher than in other pre-slaughter events. It is concluded that increasing PDF above 3 hours had no effects on heart

A DIALÉTICA PROUDHONIANA: ALGUNS DIÁLOGOS CONTEMPORÂNEOS

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Renata Monteiro

2015-02-01

Full Text Available Renata Monteiro, Gustavo Pereira DOI: 10.12957/periferia.2013.15328Este estudo se baseia em breve análise bibliográfica, tendo como referencial o conceito de dialética de Pierre Joseph Proudhon no contexto histórico do século XIX. De início, identifica-se que a existência da gestão política e social significa uma intervenção opressora sobre o povo, exercendo poder sobre a vida social, o que provoca respostas de iniciativas geridas por lógicas autossustentáveis de emancipação. Assim, articula sua contribuição em diálogo com a Sociologia das Ausências, de Boaventura de Sousa Santos, a fim de pensar a dilatação do momento presente como alternativa contra-hegemônica. A dialética proudhoniana, entendida como embates dos opostos estabelecidos em uma realidade plural, evidencia outras lógicas, como as iniciativas autogestionárias, que são, em si, parte de um processo revolucionário.

Comparison of heterologous xylose transporters in recombinant Saccharomyces cerevisiae

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Hahn-Hägerdal Bärbel

2010-03-01

Full Text Available Abstract Background Baker's yeast (Saccharomyces cerevisiae has been engineered for xylose utilization to enable production of fuel ethanol from lignocellulose raw material. One unresolved challenge is that S. cerevisiae lacks a dedicated transport system for pentose sugars, which means that xylose is transported by non-specific Hxt transporters with comparatively low transport rate and affinity for xylose. Results In this study, we compared three heterologous xylose transporters that have recently been shown to improve xylose uptake under different experimental conditions. The transporters Gxf1, Sut1 and At5g59250 from Candida intermedia, Pichia stipitis and Arabidopsis thaliana, respectively, were expressed in isogenic strains of S. cerevisiae and the transport kinetics and utilization of xylose was evaluated. Expression of the Gxf1 and Sut1 transporters led to significantly increased affinity and transport rates of xylose. In batch cultivation at 4 g/L xylose concentration, improved transport kinetics led to a corresponding increase in xylose utilization, whereas no correlation could be demonstrated at xylose concentrations greater than 15 g/L. The relative contribution of native sugar transporters to the overall xylose transport capacity was also estimated during growth on glucose and xylose. Conclusions Kinetic characterization and aerobic batch cultivation of strains expressing the Gxf1, Sut1 and At5g59250 transporters showed a direct relationship between transport kinetics and xylose growth. The Gxf1 transporter had the highest transport capacity and the highest xylose growth rate, followed by the Sut1 transporter. The range in which transport controlled the growth rate was determined to between 0 and 15 g/L xylose. The role of catabolite repression in regulation of native transporters was also confirmed by the observation that xylose transport by native S. cerevisiae transporters increased significantly during cultivation in xylose and

Cellular responses of Saccharomyces cerevisiae to DNA damage

International Nuclear Information System (INIS)

Ciesla, Z.; Sledziewska-Gojska, E.; Nowicka, A.; Mieczkowski, P.; Fikus, M.U.; Koprowski, P.

1998-01-01

Full text. Several experimental strategies have been used to study responses of S. cerevisiae cells to DNA damage. One approach was based on the isolation of novel genes, the expression of which is induced by lesions in DNA. One of these genes, DIN7, was cloned and partially characterized previously. The product of DIN7 belongs to a large family of proteins involved in DNA repair and mutagenesis. This family includes Rad2, Rad27 and ExoI proteins of S. cerevisiae and their respective human homologues, all of which are endowed with DNA nuclease activity. To study cellular function of Din7 we constructed the pPK3 plasmid carrying DIN7 fused to the GAL1 promoter. Effects of DIN7 overproduction on the phenotypes of wild-type cells and of rad27 and exoI mutants were examined. Overproduction of Din7 does not seem to affect the proficiency of wild-type S. cerevisiae cells in recombination and mutagenesis. Also, overexpression of DIN7 does not suppress the deficiency of the EXOI gene product, the closest homologue of Din7, both in recombination and in controlling the fidelity of DNA replication. Unexpectedly, we found that elevated levels of Din7 result in a very high frequency of mitochondrial rho - mutants. A high frequency of production of rho - mutants wa s also observed in strains defective in the functioning of the Dun1 protein kinase involved in signal transmission in cells exposed to DNA damaging agents. Interestingly, deficiency of Dun1 results also in a significant derepression of the DIN7 gene. Experiments are under way to distinguish whether a high cellular level of Din7 specifically decreases stability of mitochondrial DNA or affects stability of chromosomal DNA as well. Analysis of previously constructed S. cerevisiae strains carrying random geno mic fusions with reporter lacZ gene, allowed us to identify the reading frame YBR173c, on chromosome II as a novel damage inducible gene - DIN8. We have shown that DIN8-lacZ fusion is induced in yeast cells treated

Glucose-free fructose production from Jerusalem artichoke using a recombinant inulinase-secreting Saccharomyces cerevisiae strain.

Science.gov (United States)

Yu, Jing; Jiang, Jiaxi; Ji, Wangming; Li, Yuyang; Liu, Jianping

2011-01-01

Using inulin (polyfructose) obtained from Jerusalen artichokes, we have produced fructose free of residual glucose using a recombinant inulinase-secreting strain of Saccharomyces cerevisiae in a one-step fermentation of Jerusalem artichoke tubers. For producing fructose from inulin, a recombinant inulinase-producing Saccharomyce cerevisiae strain was constructed with a deficiency in fructose uptake by disruption of two hexokinase genes hxk1 and hxk2. The inulinase gene introduced into S. cerevisiae was cloned from Kluyveromyces cicerisporus. Extracellular inulinase activity of the recombinant hxk-mutated S. cerevisiae strain reached 31 U ml(-1) after 96 h growth. When grown in a medium containing Jerusalem artichoke tubers as the sole component without any additives, the recombinant yeast accumulated fructose up to 9.2% (w/v) in the fermentation broth with only 0.1% (w/v) glucose left after 24 h.

Processamento visual da forma: análise de sistema linear e alguns paradigmas psicofísicos Visual processing of form: linear system analysis and some psychophysical paradigms

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Natanael Antonio dos Santos

2002-01-01

Full Text Available O objetivo deste trabalho é discutir alguns aspectos conceituais básicos da análise de Fourier enquanto ferramenta que fundamenta a perspectiva de filtros ou canais múltiplos de freqüências espaciais no estudo do processamento visual da forma. Serão também discutidos alguns dos principais paradigmas psicofísicos utilizados para caracterizar a resposta do sistema visual humano para filtros de freqüências espaciais de banda estreita. A análise de sistema linear e alguns paradigmas psicofísicos têm contribuído para o desenvolvimento teórico da percepção e do processamento visual da forma.The goal of this work is to discuss some basic aspects of Fourier analysis as a tool to be used in the approach of multiple channels of spatial frequencies on the study of visual processing of form. Some of the psychophysical paradigms more frequently used to characterize response of the human visual system to spatial frequency filter of narrow-band. The linear system analysis and some psychophysical paradigms have contributed to theoretical development of perception and of the visual processing of form.

Removal of lead, mercury and nickel using the yeast Saccharomyces cerevisiae

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Cherlys Infante J.

2014-06-01

Full Text Available Objective. In this study the biomass of the yeast Saccharomyces cerevisiae was used to remove lead, mercury and nickel in the form of ions dissolved in water. Materials and methods. Synthetic solutions were prepared containing the three heavy metals, which were put in contact with viable microorganisms at different conditions of pH, temperature, aeration and agitation. Results. Both individual variables and the interaction effects influenced the biosorption process. Throughout the experimental framework it was observed that the biomass of Saccharomyces cerevisiae removed a higher percentage of lead (86.4% as compared to mercury and nickel (69.7 and 47.8% respectively. When the pH was set at a value of 5 the effect was positive for all three metals. Conclusions. pH was the variable that had a greater influence on the biosorption of lead on the biomass of Saccharomyces cerevisiae. The affinity of the heavy metals for the biomass followed the order Pb>Hg>Ni.

Proteome-wide analysis of lysine acetylation suggests its broad regulatory scope in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Henriksen, Peter; Wagner, Sebastian Alexander; Weinert, Brian Tate

2012-01-01

Post-translational modification of proteins by lysine acetylation plays important regulatory roles in living cells. The budding yeast Saccharomyces cerevisiae is a widely used unicellular eukaryotic model organism in biomedical research. S. cerevisiae contains several evolutionary conserved lysine...... acetyltransferases and deacetylases. However, only a few dozen acetylation sites in S. cerevisiae are known, presenting a major obstacle for further understanding the regulatory roles of acetylation in this organism. Here we use high resolution mass spectrometry to identify about 4000 lysine acetylation sites in S....... cerevisiae. Acetylated proteins are implicated in the regulation of diverse cytoplasmic and nuclear processes including chromatin organization, mitochondrial metabolism, and protein synthesis. Bioinformatic analysis of yeast acetylation sites shows that acetylated lysines are significantly more conserved...

Prevenção e psicanálise : contribuição ao debate a partir da clínica institucional com crianças desnutridas

OpenAIRE

Neves, Beatriz Sernache de Castro

2015-01-01

O presente trabalho tem como objetivo pesquisar e problematizar a noção de prevenção em Psicanálise. As políticas públicas que contemplam a primeira infância focam muito na ideia de prevenção e promoção de saúde. Essa noção também existe nas práticas de saúde mental, tornando-se interessante analisar como a Psicanálise pode contribuir nesse contexto. Uma busca sobre esse tema nos principais autores da Psicanálise revelou alguns posicionamentos sobre o assunto. Juntaram-se a esses alguns conce...

L'Amor com aventura pedagògica

OpenAIRE

Sande Navarro, Jessica de

2016-01-01

Aquest treball analitza les tesis i concepcions sobre l’amor que Plató va exposar en algunes de les seves obres, principalment: Lisis, El Banquet i Fedre. L’estudi analitza el que Plató entén per amor, com elabora la seva pròpia eròtica i els elements que la separen de l’eròtica tradicional i també pretén comprovar si existeix una continuïtat sobre el concepte d’eros o amor platònic. Per portar a terme aquesta tasca s’acosta a les interpretacions d’alguns autors, com ara la que Michel Foucaul...

Torulaspora delbrueckii contribution in mixed brewing fermentations with different Saccharomyces cerevisiae strains.

Science.gov (United States)

Canonico, Laura; Comitini, Francesca; Ciani, Maurizio

2017-10-16

In recent years, there has been growing demand for distinctive high quality beer. Fermentation management has a fundamental role in beer quality and the levels of aroma compounds. Use of non-conventional yeast has been proposed to enhance beer bioflavor. In the present work we investigated mixed fermentations using three commercial Saccharomyces cerevisiae strains, without and with addition of a selected Torulaspora delbrueckii strain evaluating their interactions, as well as the aroma profiles. At the S. cerevisiae/T. delbrueckii co-inoculation ratio of 1:20, viable cell counts indicated that T. delbrueckii dominated all of the three combinations. In the mixed fermentations, T. delbrueckii provided higher levels of higher alcohols (excepting of β-phenyl ethanol), in contrast to data obtained in winemaking, where higher alcohols had lower levels. Moreover, mixed fermentations showed significantly higher ethyl acetate (from 5 to 16mg/L) and isoamyl acetate (from 0.019 to 0.128mg/L), and were generally lower in ethyl hexanoate and ethyl octanoate. Therefore, irrespective of S. cerevisiae strain, T. delbrueckii influenced on all mixed fermentations. On the other hand, the mixed fermentations were also affected by each of the three S. cerevisiae strains, which resulted in beers with distinctive flavors. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of fermentation by Saccharomyces cerevisiae and ...

African Journals Online (AJOL)

yassine

2013-02-13

Feb 13, 2013 ... Full Length Research Paper. Effect of Saccharomyces cerevisiae fermentation on the ... 2003). Besides, several alcoholic beverages such as wine or liqueurs are obtained from fruit juices fermented by Saccharomyces ..... (2003). Kinetics of pigment release from hairy root cultures of Beta vulgaris under the ...

Characterisation of Saccharomyces cerevisiae hybrids selected for ...

African Journals Online (AJOL)

Wine yeasts (Saccharomyces cerevisiae) vary in their ability to develop the full aroma potential of Sauvignon blanc wine due to an inability to release volatile thiols. Subsequently, the use of 'thiolreleasing' wine yeasts (TRWY) has increased in popularity. However, anecdotal evidence suggests that some commercially ...

Hybridization of Palm Wine Yeasts ( Saccharomyces Cerevisiae ...

African Journals Online (AJOL)

Haploid auxotrophic strains of Saccharomyces cerevisiae were selected from palm wine and propagated by protoplast fusion with Brewers yeast. Fusion resulted in an increase in both ethanol production and tolerance against exogenous ethanol. Mean fusion frequencies obtained for a mating types ranged between 8 x ...

Sporulation in the Budding Yeast Saccharomyces cerevisiae

Science.gov (United States)

Neiman, Aaron M.

2011-01-01

In response to nitrogen starvation in the presence of a poor carbon source, diploid cells of the yeast Saccharomyces cerevisiae undergo meiosis and package the haploid nuclei produced in meiosis into spores. The formation of spores requires an unusual cell division event in which daughter cells are formed within the cytoplasm of the mother cell. This process involves the de novo generation of two different cellular structures: novel membrane compartments within the cell cytoplasm that give rise to the spore plasma membrane and an extensive spore wall that protects the spore from environmental insults. This article summarizes what is known about the molecular mechanisms controlling spore assembly with particular attention to how constitutive cellular functions are modified to create novel behaviors during this developmental process. Key regulatory points on the sporulation pathway are also discussed as well as the possible role of sporulation in the natural ecology of S. cerevisiae. PMID:22084423

Incorporating Protein Biosynthesis into the Saccharomyces cerevisiae Genome-scale Metabolic Model

DEFF Research Database (Denmark)

Olivares Hernandez, Roberto

Based on stoichiometric biochemical equations that occur into the cell, the genome-scale metabolic models can quantify the metabolic fluxes, which are regarded as the final representation of the physiological state of the cell. For Saccharomyces Cerevisiae the genome scale model has been construc......Based on stoichiometric biochemical equations that occur into the cell, the genome-scale metabolic models can quantify the metabolic fluxes, which are regarded as the final representation of the physiological state of the cell. For Saccharomyces Cerevisiae the genome scale model has been...

Regulation of Lactobacillus plantarum contamination on the carbohydrate and energy related metabolisms of Saccharomyces cerevisiae during bioethanol fermentation.

Science.gov (United States)

Dong, Shi-Jun; Lin, Xiang-Hua; Li, Hao

2015-11-01

During the industrial bioethanol fermentation, Saccharomyces cerevisiae cells are often stressed by bacterial contaminants, especially lactic acid bacteria. Generally, lactic acid bacteria contamination can inhibit S. cerevisiae cell growth through secreting lactic acid and competing with yeast cells for micronutrients and living space. However, whether are there still any other influences of lactic acid bacteria on yeast or not? In this study, Lactobacillus plantarum ATCC 8014 was co-cultivated with S. cerevisiae S288c to mimic the L. plantarum contamination in industrial bioethanol fermentation. The contaminative L. plantarum-associated expression changes of genes involved in carbohydrate and energy related metabolisms in S. cerevisiae cells were determined by quantitative real-time polymerase chain reaction to evaluate the influence of L. plantarum on carbon source utilization and energy related metabolism in yeast cells during bioethanol fermentation. Contaminative L. plantarum influenced the expression of most of genes which are responsible for encoding key enzymes involved in glucose related metabolisms in S. cerevisiae. Specific for, contaminated L. plantarum inhibited EMP pathway but promoted TCA cycle, glyoxylate cycle, HMP, glycerol synthesis pathway, and redox pathway in S. cerevisiae cells. In the presence of L. plantarum, the carbon flux in S. cerevisiae cells was redistributed from fermentation to respiratory and more reducing power was produced to deal with the excess NADH. Moreover, L. plantarum contamination might confer higher ethanol tolerance to yeast cells through promoting accumulation of glycerol. These results also highlighted our knowledge about relationship between contaminative lactic acid bacteria and S. cerevisiae during bioethanol fermentation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Obtención de un aditivo microbiano producto de la fermentación de los desechos del pastificio por Aspergillus niger y Saccharomyces cerevisiae y su evaluación nutricional en pollos de engorde

OpenAIRE

Domínguez, Gabriela; Bertsch, Annalisse; Mazzani, Claudio; Luzón, Odalis; De Basilio, Vasco

2011-01-01

En el presente trabajo se obtuvo un aditivo microbiano por fermentación de los residuos del pastificio compuesto por almidón (79,96%) y proteínas (11,96%) utilizando Aspergillus niger y Saccharomyces cerevisiae en cocultivo y se evaluó el efecto de inclusión en la dieta de pollos de engorde sobre los parámetros productivos. El aditivo se incluyó a (30 (T1); 300 (T2) y 3.000 (T3) mg / kg) respecto a un control sin la adición del aditivo (T0), utilizando un diseño completam...

Ocorrência de Vibrio vulnificus em alguns alimentos de origem marinha

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Maria Luz Garcia Moreno

1997-08-01

Full Text Available Vibrio vulnificus é uma bactéria Gram-negativa que habita águas marinhas. É patogênica para o homem e a doença está associada ao consumo de frutos do mar, com aproximadamente 60% dos casos sendo fatais em pacientes imunocomprometidos. O objetivo desta pesquisa foi estudar a ocorrência de V. vulnificus em amostras de alguns alimentos de origem marinha. As amostras de ostras, mariscos e camarões foram coletadas nos períodos de abril-agosto de 1993, maio-setembro de 1994 e fevereiro de 1995. De 55 amostras de ostras, 36 (65% foram positivas para V. vulnificus; das 19 amostras de mariscos, 8 (42,1% foram positivas e das 7 amostras de camarão, 1 (4,3% foi positiva para esta bactéria. Os resultados permitiram-nos concluir que a bactéria foi recuperada durante todos os meses de análise, demonstrando que estes alimentos, principalmente quando consumidos crus, são potencialmente perigosos para os seres humanos na faixa de risco.

Saccharomyces cerevisiae metabolism in ecological context

OpenAIRE

Jouhten, Paula; Ponomarova, Olga; González García, Ramón; Patil, Kiran R.

2016-01-01

The architecture and regulation of Saccharomyces cerevisiae metabolic network are among the best studied owing to its widespread use in both basic research and industry. Yet, several recent studies have revealed notable limitations in explaining genotype?metabolic phenotype relations in this yeast, especially when concerning multiple genetic/environmental perturbations. Apparently unexpected genotype?phenotype relations may originate in the evolutionarily shaped cellular operating principles ...

Energetic and metabolic transient response of Saccharomyces cerevisiae to benzoic acid.

Science.gov (United States)

Kresnowati, M T A P; van Winden, W A; van Gulik, W M; Heijnen, J J

2008-11-01

Saccharomyces cerevisiae is known to be able to adapt to the presence of the commonly used food preservative benzoic acid with a large energy expenditure. Some mechanisms for the adaptation process have been suggested, but its quantitative energetic and metabolic aspects have rarely been discussed. This study discusses use of the stimulus response approach to quantitatively study the energetic and metabolic aspects of the transient adaptation of S. cerevisiae to a shift in benzoic acid concentration, from 0 to 0.8 mM. The information obtained also serves as the basis for further utilization of benzoic acid as a tool for targeted perturbation of the energy system, which is important in studying the kinetics and regulation of central carbon metabolism in S. cerevisiae. Using this experimental set-up, we found significant fast-transient (< 3000 s) increases in O(2) consumption and CO(2) production rates, of approximately 50%, which reflect a high energy requirement for the adaptation process. We also found that with a longer exposure time to benzoic acid, S. cerevisiae decreases the cell membrane permeability for this weak acid by a factor of 10 and decreases the cell size to approximately 80% of the initial value. The intracellular metabolite profile in the new steady-state indicates increases in the glycolytic and tricarboxylic acid cycle fluxes, which are in agreement with the observed increases in specific glucose and O(2) uptake rates.

Expression of a Dianthus flavonoid glucosyltransferase in Saccharomyces cerevisiae for whole-cell biocatalysis.

Science.gov (United States)

Werner, Sean R; Morgan, John A

2009-07-15

Glycosyltransferases are promising biocatalysts for the synthesis of small molecule glycosides. In this study, Saccharomyces cerevisiae expressing a flavonoid glucosyltransferase (GT) from Dianthus caryophyllus (carnation) was investigated as a whole-cell biocatalyst. Two yeast expression systems were compared using the flavonoid naringenin as a model substrate. Under in vitro conditions, naringenin-7-O-glucoside was formed and a higher specific glucosyl transfer activity was found using a galactose inducible expression system compared to a constitutive expression system. However, S. cerevisiae expressing the GT constitutively was significantly more productive than the galactose inducible system under in vivo conditions. Interestingly, the glycosides were recovered directly from the culture broth and did not accumulate intracellularly. A previously uncharacterized naringenin glycoside formed using the D. caryophyllus GT was identified as naringenin-4'-O-glucoside. It was found that S. cerevisiae cells hydrolyze naringenin-7-O-glucoside during whole-cell biocatalysis, resulting in a low final glycoside titer. When phloretin was added as a substrate to the yeast strain expressing the GT constitutively, the natural product phlorizin was formed. This study demonstrates S. cerevisiae is a promising whole-cell biocatalyst host for the production of valuable glycosides.

Genomic reconstruction to improve bioethanol and ergosterol production of industrial yeast Saccharomyces cerevisiae.

Science.gov (United States)

Zhang, Ke; Tong, Mengmeng; Gao, Kehui; Di, Yanan; Wang, Pinmei; Zhang, Chunfang; Wu, Xuechang; Zheng, Daoqiong

2015-02-01

Baker's yeast (Saccharomyces cerevisiae) is the common yeast used in the fields of bread making, brewing, and bioethanol production. Growth rate, stress tolerance, ethanol titer, and byproducts yields are some of the most important agronomic traits of S. cerevisiae for industrial applications. Here, we developed a novel method of constructing S. cerevisiae strains for co-producing bioethanol and ergosterol. The genome of an industrial S. cerevisiae strain, ZTW1, was first reconstructed through treatment with an antimitotic drug followed by sporulation and hybridization. A total of 140 mutants were selected for ethanol fermentation testing, and a significant positive correlation between ergosterol content and ethanol production was observed. The highest performing mutant, ZG27, produced 7.9 % more ethanol and 43.2 % more ergosterol than ZTW1 at the end of fermentation. Chromosomal karyotyping and proteome analysis of ZG27 and ZTW1 suggested that this breeding strategy caused large-scale genome structural variations and global gene expression diversities in the mutants. Genetic manipulation further demonstrated that the altered expression activity of some genes (such as ERG1, ERG9, and ERG11) involved in ergosterol synthesis partly explained the trait improvement in ZG27.

Sobre a vulnerabilidade socioeconômica e civil: Estados Unidos, França e Brasil

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Kowarick Lúcio

2003-01-01

Full Text Available O artigo analisa a evolução do debate acerca da vulnerabilidade socioeconômica nos Estados Unidos e na França, com comentários finais sobre a atualidade brasileira. No caso norte-americano, a discussão é abertamente política-ideológica - culpar ou não as vítimas por sua situação de marginalização e anomia - e centra-se em torno do conceito de underclass, o que leva alguns autores a responsabilizar os programas de bem-estar no fomento da ociosidade e desorganização familiar. No caso francês, ao contrário, seguindo a tradição republicana, os diagnósticos e as propostas enfatizam a necessidade de uma forte presença estatal, que deve fornecer os meios de (re inserção dos grupos marginalizados. A polêmica se dá em torno dos conceitos de exclusão social e desafiliação. O ensaio não visa realizar um balanço crítico da literatura, mas, a partir de obras seminais, mostrar os parâmetros que essa problemática teórica e empírica adquire em função das especificidades de cada ambiente político nacional; daí as observações finais sobre a sociedade brasileira.

Probiotic Activity of Saccharomyces cerevisiae var. boulardii Against Human Pathogens

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Katarzyna Rajkowska

2012-01-01

Full Text Available Infectious diarrhoea is associated with a modification of the intestinal microflora and colonization of pathogenic bacteria. Tests were performed for seven probiotic yeast strains of Saccharomyces cerevisiae var. boulardii, designated for the prevention and treatment of diarrhoea. To check their possible effectiveness against diarrhoea of different etiologies, the activity against a variety of human pathogenic or opportunistic bacteria was investigated in vitro. In mixed cultures with S. cerevisiae var. boulardii, a statistically significant reduction was observed in the number of cells of Listeria monocytogenes, Pseudomonas aeruginosa and Staphylococcus aureus, by even 55.9 % in the case of L. monocytogenes compared with bacterial monocultures. The influence of yeasts was mostly associated with the shortening of the bacterial lag phase duration, more rapid achievement of the maximum growth rates, and a decrease by 4.4–57.1 % (L. monocytogenes, P. aeruginosa, or an increase by 1.4–70.6 % (Escherichia coli, Enterococcus faecalis, Salmonella Typhimurium in the exponential growth rates. Another issue included in the research was the ability of S. cerevisiae var. boulardii to bind pathogenic bacteria to its cell surface. Yeasts have shown binding capacity of E. coli, S. Typhimurium and additionally of S. aureus, Campylobacter jejuni and E. faecalis. However, no adhesion of L. monocytogenes and P. aeruginosa to the yeast cell wall was noted. The probiotic activity of S. cerevisiae var. boulardii against human pathogens is related to a decrease in the number of viable and active cells of bacteria and the binding capacity of yeasts. These processes may limit bacterial invasiveness and prevent bacterial adherence and translocation in the human intestines.

Peran Direct Fed Microbials (DFM Saccharomyces cerevisiae dan Aspergillus oryzae terhadap Produktivitas Ternak Ruminansia : Review

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H. Suryani

2015-02-01

Full Text Available Mikroorganisme yang biasa digunakan dalam pakan ternak ruminansia biasanya berupa probiotik. Probiotik memiliki makna yang bersepadanan dengan Direct Fed Microbials (DFM. Penambahan DFM jenis Saccharomyces cerevisiae dan Aspergillus oryzae pada pakan ternak ruminansia mampu memanipulasi rumen dengan meningkatkan populasi bakteri pemecah serat sehingga dapat meningkatkan kecernaan dan meningkatkan bobot badan. Mekanisme kerja S. cerevisiae dan A. oryzae yang masuk kedalam tubuh ternak dan mempengaruhi pencernaan atau penyerapan, ada yang sudah diketahui secara jelas tetapi ada juga yang masih berupa hipotesa. Pemanfaatan DFM jenis S. cerevisiae dan A. oryzae secara tunggal maupun kombinasi sebagian telah diamati dan memberikan respon positif.

O jornalismo e a construção do verdadeiro no campo econômico: uma análise à luz das reflexões bakhtiana e foucaultiana sobre discursos

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Hérica Lene

2011-01-01

Full Text Available

O objetivo deste artigo é articular a construção do verdadeiro no campo econômico e os discursos produzidos pelo jornalismo sobre esta área. A questão que nos instiga é: como as notícias ajudam a construir uma “realidade” sobre o campo econômico? Partimos da premissa de que o noticiário de economia se pauta, principalmente, pelos prognósticos e não apenas pelos relatos de acontecimentos do presente. Com isso, muitas vezes, antecipam situações e provocam mudanças no mercado. O corpus de análise é constituído de edições dos dois principais jornais do país – O Globo e Folha de S. Paulo – de julho de 1994, mês de lançamento do Plano Real. Partindo das reflexões sobre a questão da comunicação e do discurso de Mikhail Bakhtin e de Michel Foucault, e de outros aportes teóricos, são analisados alguns aspectos da cobertura jornalística de economia.

Trilhas metodológicas sobre saúde e mídias sociais: uma aproximação da produção científica sobre o tema.

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Aedê Gomes CADAXA

2014-12-01

Full Text Available A apropriação pela Saúde das Tecnologias de Informação e Comunicação (TICs, cada vez mais populares, resulta em usos pessoais, acadêmicos e institucionais o mais diversos, quando tratamos do compartilhamento de informações e experiências sobre saúde. Nesse contexto, interessa-nos o mapeamento das investigações que se referem à saúde e os populares sites de “redes sociais”, como Facebook e o Twitter, uma das maiores expressões dessa sociabilidade media pela internet. Como primeira aproximação do campo, buscou-se identificar estudos brasileiros que tivessem por objeto apresentar o estado da arte ou revisar a produção científica relacionadas à saúde e as TICs, em especial as mídias sociais. Bem como estudos e literatura de outras áreas e também nacionalidades que auxiliem na identificação de alguns caminhos metodológicos a trilhar, em um campo ainda em consolidação como o da pesquisa envolvendo a internet e a saúde.

O darwinismo e o sagrado na segunda metade do século XIX: alguns aspectos ideológicos e metafísicos do debate Darwinism and "the sacred" during the second half of the 19 th century: some ideological and metaphysical features of the debate

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Juanma Sánchez Arteaga

2008-01-01

Full Text Available O artigo analisa alguns aspectos ideológicos e metafísicos da transformação do imaginário ocidental sobre a origem da espécie humana - a velha questão, "quem somos?", respondida de formas diversas pelo cristianismo e pela biologia evolutiva - na segunda metade do século XIX. Nesse período passa-se do predomínio da antropogênese cristã ao das explicações evolucionistas. Analisa-se a confrontação histórica que teve lugar, nesse período, entre alguns dos principais defensores científicos do evolucionismo materialista - Haeckel, Clémence Royer e Huxley - e os defensores de uma antropologia anti-evolucionista e cristã. Analisam-se brevemente os pontos principais da crítica de Darwin à religião e algumas similitudes e discrepâncias de sua crítica ao pensamento religioso com relação à realizada por Marx no mesmo período. Determinados aspectos ideológico-metafísicos foram componentes essenciais do discurso darwinista na sua luta para se impor às narrativas do cristianismo sobre a origem do ser humano.This paper analyzes some of the ideological and metaphysical features of the historical transformation of Western imaginary on human origins, during the second half of 19th Century. In this period, predominance of the Christian Natural Theology accounts about anthropogenesis gave place to a new paradigm, based on evolutionary biological explanations. We thus analyze the historical confrontation that took place between prominent materialistic scientists - Haeckel, Royer, Huxley - defending evolutionary theories, on one hand, and advocates of a non-evolutionist anthropology linked to Christian believe in Creation, on the other. This paper analyzes the main features of Darwin's criticism of religious thought, based on naturalistic basis, and presents some similarities and differences with the critique of religion made by Marx in the same period. Darwinism included some metaphysical and ideological elements as essential parts of

Genome-wide screening of Saccharomyces cerevisiae genes regulated by vanillin.

Science.gov (United States)

Park, Eun-Hee; Kim, Myoung-Dong

2015-01-01

During pretreatment of lignocellulosic biomass, a variety of fermentation inhibitors, including acetic acid and vanillin, are released. Using DNA microarray analysis, this study explored genes of the budding yeast Saccharomyces cerevisiae that respond to vanillin-induced stress. The expression of 273 genes was upregulated and that of 205 genes was downregulated under vanillin stress. Significantly induced genes included MCH2, SNG1, GPH1, and TMA10, whereas NOP2, UTP18, FUR1, and SPR1 were down regulated. Sequence analysis of the 5'-flanking region of upregulated genes suggested that vanillin might regulate gene expression in a stress response element (STRE)-dependent manner, in addition to a pathway that involved the transcription factor Yap1p. Retardation in the cell growth of mutant strains indicated that MCH2, SNG1, and GPH1 are intimately involved in vanillin stress response. Deletion of the genes whose expression levels were decreased under vanillin stress did not result in a notable change in S. cerevisiae growth under vanillin stress. This study will provide the basis for a better understanding of the stress response of the yeast S. cerevisiae to fermentation inhibitors.

Irradiation effects on the alcohol fermentation ability of saccharomyces cerevisiae

International Nuclear Information System (INIS)

Sadi, Suharni

1987-01-01

Irradiation effects on the alcohol fermentation ability of saccharomyces cerevisiae. S. cerevisiae suspensions of 1.5x10 8 clls/ml were exposed to single and fractionated doses of gamma irradiation, i.e. 0; 0.30; 0.60; 0.90; and 1.20 kGy in aerobic condition at dose rate of 1.63 kGy/hour. The fractionated doses were given with time interval of 15, 30 and 45 minutes. The fermentation was held at 30 0 C for 40 hours. It is seen that an increase of alcohol production was obtained when cells were irradiated at 0.60 kGy, although the result has no significant difference statistically with control. At the dose of 1.20 kGy the alcohol fermentation ability of S. cerevisiae decreased drastically as compared to control. Irradiation using single or fractionated doses with time interval of 15-45 minutes did not influence the alcohol production. Comparing the time interval of 45 minutes at 0.60 kGy and at 1.20 kGy, it appeared that the yield of alcohol was different. (author). 17 refs.; 4 figs

Saccharomyces cerevisiae Boulardii Reduces the Deoxynivalenol-Induced Alteration of the Intestinal Transcriptome

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Imourana Alassane-Kpembi

2018-05-01

Full Text Available Type B trichothecene mycotoxin deoxynivalenol (DON is one of the most frequently occurring food contaminants. By inducing trans-activation of a number of pro-inflammatory cytokines and increasing the stability of their mRNA, trichothecene can impair intestinal health. Several yeast products, especially Saccharomyces cerevisiae, have the potential for improving the enteric health of piglets, but little is known about the mechanisms by which the administration of yeast counteracts the DON-induced intestinal alterations. Using a pig jejunum explant model, a whole-transcriptome analysis was performed to decipher the early response of the small intestine to the deleterious effects of DON after administration of S. cerevisiae boulardii strain CNCM I-1079. Compared to the control condition, no differentially expressed gene (DE was observed after treatment by yeast only. By contrast, 3619 probes—corresponding to 2771 genes—were differentially expressed following exposure to DON, and 32 signaling pathways were identified from the IPA software functional analysis of the set of DE genes. When the intestinal explants were treated with S. cerevisiae boulardii prior to DON exposure, the number of DE genes decreased by half (1718 probes corresponding to 1384 genes. Prototypical inflammation signaling pathways triggered by DON, including NF-κB and p38 MAPK, were reversed, although the yeast demonstrated limited efficacy toward some other pathways. S. cerevisiae boulardii also restored the lipid metabolism signaling pathway, and reversed the down-regulation of the antioxidant action of vitamin C signaling pathway. The latter effect could reduce the burden of DON-induced oxidative stress. Altogether, the results show that S. cerevisiae boulardii reduces the DON-induced alteration of intestinal transcriptome, and point to new mechanisms for the healing of tissue injury by yeast.

Saccharomyces cerevisiae Boulardii Reduces the Deoxynivalenol-Induced Alteration of the Intestinal Transcriptome.

Science.gov (United States)

Alassane-Kpembi, Imourana; Pinton, Philippe; Hupé, Jean-François; Neves, Manon; Lippi, Yannick; Combes, Sylvie; Castex, Mathieu; Oswald, Isabelle P

2018-05-15

Type B trichothecene mycotoxin deoxynivalenol (DON) is one of the most frequently occurring food contaminants. By inducing trans-activation of a number of pro-inflammatory cytokines and increasing the stability of their mRNA, trichothecene can impair intestinal health. Several yeast products, especially Saccharomyces cerevisiae , have the potential for improving the enteric health of piglets, but little is known about the mechanisms by which the administration of yeast counteracts the DON-induced intestinal alterations. Using a pig jejunum explant model, a whole-transcriptome analysis was performed to decipher the early response of the small intestine to the deleterious effects of DON after administration of S. cerevisiae boulardii strain CNCM I-1079. Compared to the control condition, no differentially expressed gene (DE) was observed after treatment by yeast only. By contrast, 3619 probes-corresponding to 2771 genes-were differentially expressed following exposure to DON, and 32 signaling pathways were identified from the IPA software functional analysis of the set of DE genes. When the intestinal explants were treated with S. cerevisiae boulardii prior to DON exposure, the number of DE genes decreased by half (1718 probes corresponding to 1384 genes). Prototypical inflammation signaling pathways triggered by DON, including NF-κB and p38 MAPK, were reversed, although the yeast demonstrated limited efficacy toward some other pathways. S. cerevisiae boulardii also restored the lipid metabolism signaling pathway, and reversed the down-regulation of the antioxidant action of vitamin C signaling pathway. The latter effect could reduce the burden of DON-induced oxidative stress. Altogether, the results show that S. cerevisiae boulardii reduces the DON-induced alteration of intestinal transcriptome, and point to new mechanisms for the healing of tissue injury by yeast.

Characterization of the Viable but Nonculturable (VBNC State in Saccharomyces cerevisiae.

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Mohammad Salma

Full Text Available The Viable But Non Culturable (VBNC state has been thoroughly studied in bacteria. In contrast, it has received much less attention in other microorganisms. However, it has been suggested that various yeast species occurring in wine may enter in VBNC following sulfite stress.In order to provide conclusive evidences for the existence of a VBNC state in yeast, the ability of Saccharomyces cerevisiae to enter into a VBNC state by applying sulfite stress was investigated. Viable populations were monitored by flow cytometry while culturable populations were followed by plating on culture medium. Twenty-four hours after the application of the stress, the comparison between the culturable population and the viable population demonstrated the presence of viable cells that were non culturable. In addition, removal of the stress by increasing the pH of the medium at different time intervals into the VBNC state allowed the VBNC S. cerevisiae cells to "resuscitate". The similarity between the cell cycle profiles of VBNC cells and cells exiting the VBNC state together with the generation rate of cells exiting VBNC state demonstrated the absence of cellular multiplication during the exit from the VBNC state. This provides evidence of a true VBNC state. To get further insight into the molecular mechanism pertaining to the VBNC state, we studied the involvement of the SSU1 gene, encoding a sulfite pump in S. cerevisiae. The physiological behavior of wild-type S. cerevisiae was compared to those of a recombinant strain overexpressing SSU1 and null Δssu1 mutant. Our results demonstrated that the SSU1 gene is only implicated in the first stages of sulfite resistance but not per se in the VBNC phenotype. Our study clearly demonstrated the existence of an SO2-induced VBNC state in S. cerevisiae and that the stress removal allows the "resuscitation" of VBNC cells during the VBNC state.

Adaption of Saccharomyces cerevisiae expressing a heterologous protein

DEFF Research Database (Denmark)

Krogh, Astrid Mørkeberg; Beck, Vibe; Højlund Christensen, Lars

2008-01-01

Production of the heterologous protein, bovine aprotinin, in Saccharomyces cerevisiae was shown to affect the metabolism of the host cell to various extent depending on the strain genotype. Strains with different genotypes, industrial and laboroatory, respectively, were investigated. The maximal...

Effect of Saccharomyces cerevisiae fermentation on the colorants of ...

African Journals Online (AJOL)

Effect of Saccharomyces cerevisiae fermentation on the colorants of heated red beetroot extracts. Hayet Ben Haj Koubaier, Ismahen Essaidi, Ahmed Snoussi, Slim Zgoulli, Mohamed Moncef Chaabouni, Phillipe Thonart, Nabiha Bouzouita ...

Improved ethanol tolerance of Saccharomyces cerevisiae in mixed cultures with Kluyveromyces lactis on high-sugar fermentation.

Science.gov (United States)

Yamaoka, Chizuru; Kurita, Osamu; Kubo, Tomoko

2014-12-01

The influence of non-Saccharomyces yeast, Kluyveromyces lactis, on metabolite formation and the ethanol tolerance of Saccharomyces cerevisiae in mixed cultures was examined on synthetic minimal medium containing 20% glucose. In the late stage of fermentation after the complete death of K. lactis, S. cerevisiae in mixed cultures was more ethanol-tolerant than that in pure culture. The chronological life span of S. cerevisiae was shorter in pure culture than mixed cultures. The yeast cells of the late stationary phase both in pure and mixed cultures had a low buoyant density with no significant difference in the non-quiescence state between both cultures. In mixed cultures, the glycerol contents increased and the alanine contents decreased when compared with the pure culture of S. cerevisiae. The distinctive intracellular amino acid pool concerning its amino acid concentrations and its amino acid composition was observed in yeast cells with different ethanol tolerance in the death phase. Co-cultivation of K. lactis seems to prompt S. cerevisiae to be ethanol tolerant by forming opportune metabolites such as glycerol and alanine and/or changing the intracellular amino acid pool. Copyright © 2014 Elsevier GmbH. All rights reserved.

Microbial cells as biosorbents for heavy metals: accumulation of Uranium by Saccharomyces cerevisiae and Pseudomonas aeruginosa

International Nuclear Information System (INIS)

Strandberg, G.W.; Shumate, S.E. II; Parrott, J.R. Jr.

1981-01-01

Uranium accumulated extracellularly on the surfaces of Saccharomyces cerevisiae cells. The rate and extent of accumulation were subject to environmental parameters, such as pH, temperature, and interference by certain anions and cations. Uranium accumulation by Pseudomonas aeruginosa occurred intracellularly and was extremely rapid (<10 s), and no response to environmental parameters could be detected. Metabolism was not required for metal uptake by either organism. Cell-bound uranium reached a concentration of 10 to 15% of the dry cell weight, but only 32% of the S. cerevisiae cells and 44% of the P. aeruginosa cells within a given population possessed visible uranium deposits when examined by electron microscopy. Rates of uranium uptake by S. cerevisiae were increased by chemical pretreatment of the cells. Uranium could be removed chemically from S. cerevisiae cells, and the cells could then be reused as a biosorbent

Impact of Commercial Strain Use on Saccharomyces cerevisiae Population Structure and Dynamics in Pinot Noir Vineyards and Spontaneous Fermentations of a Canadian Winery.

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Jonathan T Martiniuk

Full Text Available Wine is produced by one of two methods: inoculated fermentation, where a commercially-produced, single Saccharomyces cerevisiae (S. cerevisiae yeast strain is used; or the traditional spontaneous fermentation, where yeast present on grape and winery surfaces carry out the fermentative process. Spontaneous fermentations are characterized by a diverse succession of yeast, ending with one or multiple strains of S. cerevisiae dominating the fermentation. In wineries using both fermentation methods, commercial strains may dominate spontaneous fermentations. We elucidate the impact of the winery environment and commercial strain use on S. cerevisiae population structure in spontaneous fermentations over two vintages by comparing S. cerevisiae populations in aseptically fermented grapes from a Canadian Pinot Noir vineyard to S. cerevisiae populations in winery-conducted fermentations of grapes from the same vineyard. We also characterize the vineyard-associated S. cerevisiae populations in two other geographically separate Pinot Noir vineyards farmed by the same winery. Winery fermentations were not dominated by commercial strains, but by a diverse number of strains with genotypes similar to commercial strains, suggesting that a population of S. cerevisiae derived from commercial strains is resident in the winery. Commercial and commercial-related yeast were also identified in the three vineyards examined, although at a lower frequency. There is low genetic differentiation and S. cerevisiae population structure between vineyards and between the vineyard and winery that persisted over both vintages, indicating commercial yeast are a driver of S. cerevisiae population structure. We also have evidence of distinct and persistent populations of winery and vineyard-associated S. cerevisiae populations unrelated to commercial strains. This study is the first to characterize S. cerevisiae populations in Canadian vineyards.

Impact of Commercial Strain Use on Saccharomyces cerevisiae Population Structure and Dynamics in Pinot Noir Vineyards and Spontaneous Fermentations of a Canadian Winery.

Science.gov (United States)

Martiniuk, Jonathan T; Pacheco, Braydon; Russell, Gordon; Tong, Stephanie; Backstrom, Ian; Measday, Vivien

2016-01-01

Wine is produced by one of two methods: inoculated fermentation, where a commercially-produced, single Saccharomyces cerevisiae (S. cerevisiae) yeast strain is used; or the traditional spontaneous fermentation, where yeast present on grape and winery surfaces carry out the fermentative process. Spontaneous fermentations are characterized by a diverse succession of yeast, ending with one or multiple strains of S. cerevisiae dominating the fermentation. In wineries using both fermentation methods, commercial strains may dominate spontaneous fermentations. We elucidate the impact of the winery environment and commercial strain use on S. cerevisiae population structure in spontaneous fermentations over two vintages by comparing S. cerevisiae populations in aseptically fermented grapes from a Canadian Pinot Noir vineyard to S. cerevisiae populations in winery-conducted fermentations of grapes from the same vineyard. We also characterize the vineyard-associated S. cerevisiae populations in two other geographically separate Pinot Noir vineyards farmed by the same winery. Winery fermentations were not dominated by commercial strains, but by a diverse number of strains with genotypes similar to commercial strains, suggesting that a population of S. cerevisiae derived from commercial strains is resident in the winery. Commercial and commercial-related yeast were also identified in the three vineyards examined, although at a lower frequency. There is low genetic differentiation and S. cerevisiae population structure between vineyards and between the vineyard and winery that persisted over both vintages, indicating commercial yeast are a driver of S. cerevisiae population structure. We also have evidence of distinct and persistent populations of winery and vineyard-associated S. cerevisiae populations unrelated to commercial strains. This study is the first to characterize S. cerevisiae populations in Canadian vineyards.

Excessive by-product formation : A key contributor to low isobutanol yields of engineered Saccharomyces cerevisiae strains

NARCIS (Netherlands)

Milne, N.S.W.; Wahl, S.A.; Van Maris, A.J.A.; Pronk, J.T.; Daran, J.M.

2016-01-01

It is theoretically possible to engineer Saccharomyces cerevisiae strains in which isobutanol is the predominant catabolic product and high-yielding isobutanol-producing strains are already reported by industry. Conversely, isobutanol yields of engineered S. cerevisiae strains reported in the

De novo production of the flavonoid naringenin in engineered Saccharomyces cerevisiae

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Koopman Frank

2012-12-01

Full Text Available Abstract Background Flavonoids comprise a large family of secondary plant metabolic intermediates that exhibit a wide variety of antioxidant and human health-related properties. Plant production of flavonoids is limited by the low productivity and the complexity of the recovered flavonoids. Thus to overcome these limitations, metabolic engineering of specific pathway in microbial systems have been envisaged to produce high quantity of a single molecules. Result Saccharomyces cerevisiae was engineered to produce the key intermediate flavonoid, naringenin, solely from glucose. For this, specific naringenin biosynthesis genes from Arabidopsis thaliana were selected by comparative expression profiling and introduced in S. cerevisiae. The sole expression of these A. thaliana genes yielded low extracellular naringenin concentrations ( Conclusion The results reported in this study demonstrate that S. cerevisiae is capable of de novo production of naringenin by coexpressing the naringenin production genes from A. thaliana and optimization of the flux towards the naringenin pathway. The engineered yeast naringenin production host provides a metabolic chassis for production of a wide range of flavonoids and exploration of their biological functions.

Anti-oxidant effects of pomegranate juice on Saccharomyces cerevisiae cell growth.

Science.gov (United States)

Aslan, Abdullah; Can, Muhammed İsmail; Boydak, Didem

2014-01-01

Pomegranate juice has a number of positive effects on both human and animal subjects. Four groups were used in this study. i: Control group, ii: H2O2 group, iii: Pomegranate juice (PJ) group and iv: PJ + H2O2 group. Following the sterilization method for pomegranate juice (10%) and H2O2 (6% v/v), Saccharomyces cerevisiae cultures were added and the cultivation incubated at 35°C for 72 hours. Fatty acids and vitamin concentrations were measured using HPLC and GC and the total protein bands profile were determined by SDS-PAGE. According to our results statistically significant differences have been determined among the study groups in terms of fatty acids and vitamin (pPomegranate juice increased vitamins, fatty acids and total protein expression in Saccharomyces cerevisiae in comparison with the control. Pomegranate juice has a positive effect on fatty acid, vitamin and protein synthesis by Saccharomyces cerevisiae. Accordingly, we believe that it has significantly decreased oxidative damage thereby making a positive impact on yeast development.

Screening of Non- Saccharomyces cerevisiae Strains for Tolerance to Formic Acid in Bioethanol Fermentation.

Science.gov (United States)

Oshoma, Cyprian E; Greetham, Darren; Louis, Edward J; Smart, Katherine A; Phister, Trevor G; Powell, Chris; Du, Chenyu

2015-01-01

Formic acid is one of the major inhibitory compounds present in hydrolysates derived from lignocellulosic materials, the presence of which can significantly hamper the efficiency of converting available sugars into bioethanol. This study investigated the potential for screening formic acid tolerance in non-Saccharomyces cerevisiae yeast strains, which could be used for the development of advanced generation bioethanol processes. Spot plate and phenotypic microarray methods were used to screen the formic acid tolerance of 7 non-Saccharomyces cerevisiae yeasts. S. kudriavzeii IFO1802 and S. arboricolus 2.3319 displayed a higher formic acid tolerance when compared to other strains in the study. Strain S. arboricolus 2.3319 was selected for further investigation due to its genetic variability among the Saccharomyces species as related to Saccharomyces cerevisiae and availability of two sibling strains: S. arboricolus 2.3317 and 2.3318 in the lab. The tolerance of S. arboricolus strains (2.3317, 2.3318 and 2.3319) to formic acid was further investigated by lab-scale fermentation analysis, and compared with S. cerevisiae NCYC2592. S. arboricolus 2.3319 demonstrated improved formic acid tolerance and a similar bioethanol synthesis capacity to S. cerevisiae NCYC2592, while S. arboricolus 2.3317 and 2.3318 exhibited an overall inferior performance. Metabolite analysis indicated that S. arboricolus strain 2.3319 accumulated comparatively high concentrations of glycerol and glycogen, which may have contributed to its ability to tolerate high levels of formic acid.

Ferrofluid modified Saccharomyces cerevisiae cells for biocatalysis

Czech Academy of Sciences Publication Activity Database

Šafaříková, Miroslava; Maděrová, Zdeňka; Šafařík, Ivo

2009-01-01

Roč. 42, - (2009), s. 521-524 ISSN 0963-9969 R&D Projects: GA MPO 2A-1TP1/094; GA MŠk(CZ) OC 157 Institutional research plan: CEZ:AV0Z60870520 Keywords : Saccharomyces cerevisiae * magnetic fluid * hydrogen peroxide Subject RIV: EI - Biotechnology ; Bionics Impact factor: 2.414, year: 2009

Substrate Channelling and Energetics of Saccharomyces cerevisiae ...

African Journals Online (AJOL)

Data collected during the high-cell-density cultivation of Saccharomyces cerevisiae DSM 2155 on glucose in a simulated five-phase feeding strategy of fed-batch process, executed on the Universal BIoprocess CONtrol (UBICON) system using 150L bioreactor over a period of 24h have been analysed. The consistency of the ...

Transcriptomic analysis of Saccharomyces cerevisiae x Saccharomyces kudriavzevii hybrids during low temperature winemaking [version 3; referees: 2 approved

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Jordi Tronchoni

2017-09-01

Full Text Available Background: Although Saccharomyces cerevisiae is the most frequently isolated species in wine fermentation, and the most studied species, other species and interspecific hybrids have greatly attracted the interest of researchers in this field in the last few years, given their potential to solve new winemaking industry challenges. S. cerevisiae x S. kudriavzevii hybrids exhibit good fermentative capabilities at low temperatures, and produce wines with smaller alcohol quantities and larger glycerol quantities, which can be very useful to solve challenges in the winemaking industry such as the necessity to enhance the aroma profile. Methods: In this study, we performed a transcriptomic study of S. cerevisiae x S. kudriavzevii hybrids in low temperature winemaking conditions. Results: The results revealed that the hybrids have acquired both fermentative abilities and cold adaptation abilities, attributed to S. cerevisiae and S. kudriavzevii parental species, respectively, showcasing their industrially relevant characteristics. For several key genes, we also studied the contribution to gene expression of each of the alleles of S. cerevisiae and S. kudriavzevii in the S. cerevisiae x S. kudriavzevii hybrids. From the results, it is not clear how important the differential expression of the specific parental alleles is to the phenotype of the hybrids. Conclusions: This study shows that the fermentative abilities of S. cerevisiae x S. kudriavzevii hybrids at low temperatures do not seem to result from differential expression of specific parental alleles of the key genes involved in this phenotype.

Expression of an Aspergillus niger Phytase Gene (phyA) in Saccharomyces cerevisiae

OpenAIRE

Han, Yanming; Wilson, David B.; Lei, Xin gen

1999-01-01

Phytase improves the bioavailability of phytate phosphorus in plant foods to humans and animals and reduces phosphorus pollution of animal waste. Our objectives were to express an Aspergillus niger phytase gene (phyA) in Saccharomyces cerevisiae and to determine the effects of glycosylation on the phytase’s activity and thermostability. A 1.4-kb DNA fragment containing the coding region of the phyA gene was inserted into the expression vector pYES2 and was expressed in S. cerevisiae as an act...

Saccharomyces cerevisiae UE-ME3 is a good strain for isoproturon biorremediation?

OpenAIRE

Candeias, M; Alves-Pereira, I; Ferreira, R

2010-01-01

Isoproturon, an herbicide of pre- and pos-emergence of Autumn-Winter crops, persists occasionally in soil, groundwater and biological systems at levels above those established by European Directives. Saccharomyces cerevisiae UE-ME3 exposed in stationary phase to 50 and 100 mM isoproturon exhibit growth rates higher than control or exposed cells to 5 and 25 mM of this phenylurea. However, in S.cerevisiae UE-ME3 grown in the presence of 5 mM isoproturon, were observed a decrease of ...

Política na hora do chá: ética e identidade no debate online sobre uma bebida

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Luis Mauro Sá Martino

2012-06-01

Full Text Available Este trabalho analisa como um debate online sobre a mudança de sabor de chá da fábrica inglesa Twinings tornou-se parte de um discurso político sobre nação e identidade cultural. A alteração foi notícia em alguns dos principais diários britânicos, repercutiu nas redes sociais e ganhou cores políticas. Foram analisados 389 comentários às matérias publicadas no The Times, The Daily Telegraph e The Mail, além de uma página no Facebook, buscando compreender as principais linhas argumentativas a partir de critérios da ética do discurso de Habermas, em sua aplicação à discussão no ambiente online. A análise apontou três aspectos: (a o uso do chá para a politização de questões cotidianas que têm relevância moral e coletiva, implicando a reafirmação de uma identidade cultural britânica (b a crítica ao caráter “estrangeiro” da marca – a fábrica foi para a Polônia em 2010 por razões comerciais; (c a influência na decisão da empresa de retomar o antigo sabor.

Influência ambiental sobre a incapacidade física: uma revisão sistemática da literatura

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Filipe Athayde

Full Text Available Resumo Indivíduos com incapacidades físicas podem, em interação com facilitadores e barreiras, modificar a sua participação em sociedade. O ambiente, no panorama da Classificação Internacional de Funcionalidade, Incapacidade e Saúde (CIF, apresenta-se com relevante papel na saúde e na expressão da funcionalidade. Dessa forma, o objetivo deste estudo foi investigar a influência de fatores ambientais sobre a incapacidade física, pautado no referencial teórico da CIF. Foi realizada uma revisão sistemática da literatura, norteada por recomendações dos documentos Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA e Strengthening the Reporting of Observational Studies in Epidemiology Statement (STROBE. Os estudos selecionados puderam reforçar os preceitos teóricos da CIF. O ambiente físico e social, de modo geral, pôde ter sua interferência atribuída a diferentes condições clínicas, especialmente em neurologia, tanto em estudos quantitativos quanto qualitativos. Limitações metodológicas foram observadas e podem ser entraves à consolidação de alguns direcionamentos, o que deve incentivar novas pesquisas sobre o tema com métodos criteriosos, instrumentos validados e amostras cuidadosamente selecionadas.

Sobre a dor e a delícia da atuação Psicológica no SUAS

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Alexandre Franca Barreto

Full Text Available Este artigo traz reflexões sobre o trabalho do psicólogo no Sistema Único de Assistência Social, com base em uma experiência de seis anos de atuação no campo e em pesquisa em serviços de execução de medidas socioeducativas e educação social de rua, nos Municípios de Olinda e Recife, PE. Após breve histórico de minha trajetória no SUAS, procuro contextualizar minha identidade no atual cenário éticopolítico da profissão, envolvido pelas transformações no contexto da formação e pelas tendências atuais nos cenários da prática psicológica em políticas públicas. Proponho alguns elementos norteadores do exercício profissional na lógica do pêndulo: o cuidar e ser cuidado, a agressividade e a passividade, escutar o Outro e falar de si, como polos por onde devemos transitar para desenvolver uma prática qualificada e criativa. Por fim, são apontados questionamentos sobre a dinâmica do psicólogo nos serviços de assistência social, com algumas recomendações para o suporte e a qualificação do trabalho.

Mudando o debate sobre o tráfico de mulheres Shifting the debate on the traffic of women

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Kamala Kempadoo

2005-12-01

Full Text Available Neste texto apresento perspectivas e abordagens importantes no debate internacional sobre o tráfico de pessoas, e sublinho alguns dos principais pontos de crítica sobre o referencial contemporâneo hegemônico, pontos esses articulados através de projetos de pesquisa-ação e de intervenções contra o tráfico nas bases da sociedade. Argumento que, a despeito de mudanças substanciais no entendimento global sobre o tráfico, fortemente influenciadas por dois discursos feministas claramente diferentes (feminismo radical e feminismo transnacional, muito do que se busca hoje em nome de uma guerra ao tráfico tem conseqüências problemáticas para comunidades pobres ao redor do mundo, e tem implicações em termos de raça e gênero. As políticas norte-americanas são aqui trazidas ao debate para ilustrar algumas dessas tendências.In this text I present central perspectives and approaches in the international debate about the trafficking of persons, and highlight some of the main points of critique about the contemporary hegemonic framework that are articulated through action-research projects and grassroots anti-trafficking interventions. I argue that despite substantial shifts in global understandings about trafficking, which are heavily influenced by two distinctly different feminist discourses (radical feminism and transnational feminism, today much of what is pursued in the name of a war on trafficking has troubling consequences for poor communities around the world, and has gendered and racialized implications. US anti-trafficking policies are drawn upon here to illustrate some of these tendencies.

Saccharomyces cerevisiae show low levels of traversal across human endothelial barrier in vitro [version 2; referees: 2 approved

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Roberto Pérez-Torrado

2017-09-01

Full Text Available Background:  Saccharomyces cerevisiae is generally considered safe, and is involved in the production of many types of foods and dietary supplements. However, some isolates, which are genetically related to strains used in brewing and baking, have shown virulent traits, being able to produce infections in humans, mainly in immunodeficient patients. This can lead to systemic infections in humans. Methods: In this work, we studied S. cerevisiae isolates in an in vitro human endothelial barrier model, comparing their behaviour with that of several strains of the related pathogens Candida glabrata and Candida albicans. Results: The results showed that this food related yeast is able to cross the endothelial barrier in vitro. However, in contrast to C. glabrata and C. albicans, S. cerevisiae showed very low levels of traversal. Conclusions: We conclude that using an in vitro human endothelial barrier model with S. cerevisiae can be useful to evaluate the safety of S. cerevisiae strains isolated from foods.

Bioconversion of lignocellulose-derived sugars to ethanol by engineered Saccharomyces cerevisiae.

Science.gov (United States)

Madhavan, Anjali; Srivastava, Aradhana; Kondo, Akihiko; Bisaria, Virendra S

2012-03-01

Lignocellulosic biomass from agricultural and agro-industrial residues represents one of the most important renewable resources that can be utilized for the biological production of ethanol. The yeast Saccharomyces cerevisiae is widely used for the commercial production of bioethanol from sucrose or starch-derived glucose. While glucose and other hexose sugars like galactose and mannose can be fermented to ethanol by S. cerevisiae, the major pentose sugars D-xylose and L-arabinose remain unutilized. Nevertheless, D-xylulose, the keto isomer of xylose, can be fermented slowly by the yeast and thus, the incorporation of functional routes for the conversion of xylose and arabinose to xylulose or xylulose-5-phosphate in Saccharomyces cerevisiae can help to improve the ethanol productivity and make the fermentation process more cost-effective. Other crucial bottlenecks in pentose fermentation include low activity of the pentose phosphate pathway enzymes and competitive inhibition of xylose and arabinose transport into the cell cytoplasm by glucose and other hexose sugars. Along with a brief introduction of the pretreatment of lignocellulose and detoxification of the hydrolysate, this review provides an updated overview of (a) the key steps involved in the uptake and metabolism of the hexose sugars: glucose, galactose, and mannose, together with the pentose sugars: xylose and arabinose, (b) various factors that play a major role in the efficient fermentation of pentose sugars along with hexose sugars, and (c) the approaches used to overcome the metabolic constraints in the production of bioethanol from lignocellulose-derived sugars by developing recombinant S. cerevisiae strains.

Engineered Production of Short-Chain Acyl-Coenzyme A Esters in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Krink-Koutsoubelis, Nicolas; Loechner, Anne C.; Lechner, Anna

2018-01-01

Short-chain acyl-coenzyme A esters serve as intermediate compounds in fatty acid biosynthesis, and the production of polyketides, biopolymers and other value-added chemicals. S. cerevisiae is a model organism that has been utilized for the biosynthesis of such biologically and economically valuable...... compounds. However, its limited repertoire of short-chain acyl-CoAs effectively prevents its application as a production host for a plethora of natural products. Therefore, we introduced biosynthetic metabolic pathways to five different acyl-CoA esters into S. cerevisiae. Our engineered strains provide......-CoA at 0.5 μM; and isovaleryl-CoA, n-butyryl-CoA, and n-hexanoyl-CoA at 6 μM each. The acyl-CoAs produced in this study are common building blocks of secondary metabolites and will enable the engineered production of a variety of natural products in S. cerevisiae. By providing this toolbox of acyl...

Characterization of vacuolar amino acid transporter from Fusarium oxysporum in Saccharomyces cerevisiae.

Science.gov (United States)

Lunprom, Siriporn; Pongcharoen, Pongsanat; Sekito, Takayuki; Kawano-Kawada, Miyuki; Kakinuma, Yoshimi; Akiyama, Koichi

2015-01-01

Fusarium oxysporum causes wilt disease in many plant families, and many genes are involved in its development or growth in host plants. A recent study revealed that vacuolar amino acid transporters play an important role in spore formation in Schizosaccharomyces pombe and Saccharomyces cerevisiae. To investigate the role of vacuolar amino acid transporters of this phytopathogenic fungus, the FOXG_11334 (FoAVT3) gene from F. oxysporum was isolated and its function was characterized. Transcription of FoAVT3 was upregulated after rapamycin treatment. A green fluorescent protein fusion of FoAvt3p was localized to vacuolar membranes in both S. cerevisiae and F. oxysporum. Analysis of the amino acid content of the vacuolar fraction and amino acid transport activities using vacuolar membrane vesicles from S. cerevisiae cells heterologously expressing FoAVT3 revealed that FoAvt3p functions as a vacuolar amino acid transporter, exporting neutral amino acids. We conclude that the FoAVT3 gene encodes a vacuolar neutral amino acid transporter.

Expression of an endoglucanase from Tribolium castaneum (TcEG1) in Saccharomyces cerevisiae.

Science.gov (United States)

Shirley, Derek; Oppert, Cris; Reynolds, Todd B; Miracle, Bethany; Oppert, Brenda; Klingeman, William E; Jurat-Fuentes, Juan Luis

2014-10-01

Insects are a largely unexploited resource in prospecting for novel cellulolytic enzymes to improve the production of ethanol fuel from lignocellulosic biomass. The cost of lignocellulosic ethanol production is expected to decrease by the combination of cellulose degradation (saccharification) and fermentation of the resulting glucose to ethanol in a single process, catalyzed by the yeast Saccharomyces cerevisiae transformed to express efficient cellulases. While S. cerevisiae is an established heterologous expression system, there are no available data on the functional expression of insect cellulolytic enzymes for this species. To address this knowledge gap, S. cerevisiae was transformed to express the full-length cDNA encoding an endoglucanase from the red flour beetle, Tribolium castaneum (TcEG1), and evaluated the activity of the transgenic product (rTcEG1). Expression of the TcEG1 cDNA in S. cerevisiae was under control of the strong glyceraldehyde-3 phosphate dehydrogenase promoter. Cultured transformed yeast secreted rTcEG1 protein as a functional β-1,4-endoglucanase, which allowed transformants to survive on selective media containing cellulose as the only available carbon source. Evaluation of substrate specificity for secreted rTcEG1 demonstrated endoglucanase activity, although some activity was also detected against complex cellulose substrates. Potentially relevant to uses in biofuel production rTcEG1 activity increased with pH conditions, with the highest activity detected at pH 12. Our results demonstrate the potential for functional production of an insect cellulase in S. cerevisiae and confirm the stability of rTcEG1 activity in strong alkaline environments. © 2013 Institute of Zoology, Chinese Academy of Sciences.

Kinetics of phosphomevalonate kinase from Saccharomyces cerevisiae.

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David E Garcia

Full Text Available The mevalonate-based isoprenoid biosynthetic pathway is responsible for producing cholesterol in humans and is used commercially to produce drugs, chemicals, and fuels. Heterologous expression of this pathway in Escherichia coli has enabled high-level production of the antimalarial drug artemisinin and the proposed biofuel bisabolane. Understanding the kinetics of the enzymes in the biosynthetic pathway is critical to optimize the pathway for high flux. We have characterized the kinetic parameters of phosphomevalonate kinase (PMK, EC 2.7.4.2 from Saccharomyces cerevisiae, a previously unstudied enzyme. An E. coli codon-optimized version of the S. cerevisiae gene was cloned into pET-52b+, then the C-terminal 6X His-tagged protein was expressed in E. coli BL21(DE3 and purified on a Ni²⁺ column. The KM of the ATP binding site was determined to be 98.3 µM at 30°C, the optimal growth temperature for S. cerevisiae, and 74.3 µM at 37°C, the optimal growth temperature for E. coli. The K(M of the mevalonate-5-phosphate binding site was determined to be 885 µM at 30°C and 880 µM at 37°C. The V(max was determined to be 4.51 µmol/min/mg enzyme at 30°C and 5.33 µmol/min/mg enzyme at 37°C. PMK is Mg²⁺ dependent, with maximal activity achieved at concentrations of 10 mM or greater. Maximum activity was observed at pH = 7.2. PMK was not found to be substrate inhibited, nor feedback inhibited by FPP at concentrations up to 10 µM FPP.

High level secretion of cellobiohydrolases by Saccharomyces cerevisiae

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Ahlgren Simon

2011-09-01

Full Text Available Abstract Background The main technological impediment to widespread utilization of lignocellulose for the production of fuels and chemicals is the lack of low-cost technologies to overcome its recalcitrance. Organisms that hydrolyze lignocellulose and produce a valuable product such as ethanol at a high rate and titer could significantly reduce the costs of biomass conversion technologies, and will allow separate conversion steps to be combined in a consolidated bioprocess (CBP. Development of Saccharomyces cerevisiae for CBP requires the high level secretion of cellulases, particularly cellobiohydrolases. Results We expressed various cellobiohydrolases to identify enzymes that were efficiently secreted by S. cerevisiae. For enhanced cellulose hydrolysis, we engineered bimodular derivatives of a well secreted enzyme that naturally lacks the carbohydrate-binding module, and constructed strains expressing combinations of cbh1 and cbh2 genes. Though there was significant variability in the enzyme levels produced, up to approximately 0.3 g/L CBH1 and approximately 1 g/L CBH2 could be produced in high cell density fermentations. Furthermore, we could show activation of the unfolded protein response as a result of cellobiohydrolase production. Finally, we report fermentation of microcrystalline cellulose (Avicel™ to ethanol by CBH-producing S. cerevisiae strains with the addition of beta-glucosidase. Conclusions Gene or protein specific features and compatibility with the host are important for efficient cellobiohydrolase secretion in yeast. The present work demonstrated that production of both CBH1 and CBH2 could be improved to levels where the barrier to CBH sufficiency in the hydrolysis of cellulose was overcome.

Excision repair and mutagenesis in Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Kilbey, Brian

1987-01-01

This and succeeding letters discuss the James and Kilbey (1977 and 1978) model for the initiation of u.v. mutagenesis in Saccharomyces cerevisiae and its application to include a number of chemical mutagens. The Baranowska et al (1987) results indicating the role of DNA replication, the differing mechanisms in Escherichia coli, are all discussed. (UK)

Improvement of Lead Tolerance of Saccharomyces cerevisiae by Random Mutagenesis of Transcription Regulator SPT3.

Science.gov (United States)

Zhu, Liying; Gao, Shan; Zhang, Hongman; Huang, He; Jiang, Ling

2018-01-01

Bioremediation of heavy metal pollution with biomaterials such as bacteria and fungi usually suffer from limitations because of microbial sensitivity to high concentration of heavy metals. Herein, we adopted a novel random mutagenesis technique called RAISE to manipulate the transcription regulator SPT3 of Saccharomyces cerevisiae to improve cell lead tolerance. The best strain Mutant VI was selected from the random mutagenesis libraries on account of the growth performance, with higher specific growth rate than the control strain (0.068 vs. 0.040 h -1 ) at lead concentration as high as 1.8 g/L. Combined with the transcriptome analysis of S. cerevisiae, expressing the SPT3 protein was performed to make better sense of the global regulatory effects of SPT3. The data analysis revealed that 57 of S. cerevisiae genes were induced and 113 genes were suppressed, ranging from those for trehalose synthesis, carbon metabolism, and nucleotide synthesis to lead resistance. Especially, the accumulation of intracellular trehalose in S. cerevisiae under certain conditions of stress is considered important to lead resistance. The above results represented that SPT3 was acted as global transcription regulator in the exponential phase of strain and accordingly improved heavy metal tolerance in the heterologous host S. cerevisiae. The present study provides a route to complex phenotypes that are not readily accessible by traditional methods.

Modelling of Ethanol Production from Red Beet Juice by Saccharomyces cerevisiae under Thermal and Acid Stress Conditions

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Donaji Jiménez-Islas

2014-01-01

Full Text Available In this work the effects of pH and temperature on ethanol production from red beet juice by the strains Saccharomyces cerevisiae ITD00196 and S. cerevisiae ATCC 9763 are studied. Logistic, Pirt, and Luedeking-Piret equations were used to describe quantitatively the microbial growth, substrate consumption, and ethanol production, respectively. The two S. cerevisiae strains used in this study were able to produce ethanol with high yield and volumetric productivity under acid and thermal stress conditions. The equations used to model the fermentation kinetics fit very well with the experimental data, thus establishing that ethanol production was growth associated under the evaluated conditions. The yeast S. cerevisiae ITD00196 had the best fermentative capacity and could be considered as an interesting option to develop bioprocesses for ethanol production.

Increasing NADH oxidation reduces overflow metabolism in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Vemuri, Goutham; Eiteman, M.A; McEwen, J.E

2007-01-01

effect is due to limited respiratory capacity or is caused by glucose-mediated repression of respiration. When respiration in S. cerevisiae was increased by introducing a heterologous alternative oxidase, we observed reduced aerobic ethanol formation. In contrast, increasing nonrespiratory NADH oxidation...... Crabtree effect.’’ The yeast Saccharomyces cerevisiae has served as an important model organism for studying the Crabtree effect. When subjected to increasing glycolytic fluxes under aerobic conditions, there is a threshold value of the glucose uptake rate at which the metabolism shifts from purely...... respiratory to mixed respiratory and fermentative. It is well known that glucose repression of respiratory pathways occurs at high glycolytic fluxes, resulting in a decrease in respiratory capacity. Despite many years of detailed studies on this subject, it is not known whether the onset of the Crabtree...

Potential application of Saccharomyces cerevisiae strains for the ...

African Journals Online (AJOL)

This paper aimed at evaluating the fermentation behavior of selected Saccharomyces cerevisiae strains in banana pulp and they were compared with commercial yeast (baker's yeast) for subsequent production of distilled spirits. Five types of microorganisms were used: Four yeast strains obtained from accredited ...

Brava gente brasileira e o "Brasil 500": o espetáculo do descobrimento

OpenAIRE

Bezerra, Kátia da Costa

2011-01-01

Tendo por base os estudos de Diana Taylor, Anthony Pagden e Jean Starobinski, este ensaio analisa a forma como o fi lme Brava gente brasileira dramatiza alguns dos confl itos presentes na reencenação da descoberta durante os festejos do “Brasil 500”. O propósito é refl etir sobre alguns dos intertextos envolvidos no processo de construção de um sentido de brasilidade.

Genome-scale reconstruction of the Saccharomyces cerevisiae metabolic network

DEFF Research Database (Denmark)

Förster, Jochen; Famili, I.; Fu, P.

2003-01-01

The metabolic network in the yeast Saccharomyces cerevisiae was reconstructed using currently available genomic, biochemical, and physiological information. The metabolic reactions were compartmentalized between the cytosol and the mitochondria, and transport steps between the compartments...

Dual utilization of NADPH and NADH cofactors enhances xylitol production in engineered Saccharomyces cerevisiae.

Science.gov (United States)

Jo, Jung-Hyun; Oh, Sun-Young; Lee, Hyeun-Soo; Park, Yong-Cheol; Seo, Jin-Ho

2015-12-01

Xylitol, a natural sweetener, can be produced by hydrogenation of xylose in hemicelluloses. In microbial processes, utilization of only NADPH cofactor limited commercialization of xylitol biosynthesis. To overcome this drawback, Saccharomyces cerevisiae D452-2 was engineered to express two types of xylose reductase (XR) with either NADPH-dependence or NADH-preference. Engineered S. cerevisiae DWM expressing both the XRs exhibited higher xylitol productivity than the yeast strain expressing NADPH-dependent XR only (DWW) in both batch and glucose-limited fed-batch cultures. Furthermore, the coexpression of S. cerevisiae ZWF1 and ACS1 genes in the DWM strain increased intracellular concentrations of NADPH and NADH and improved maximum xylitol productivity by 17%, relative to that for the DWM strain. Finally, the optimized fed-batch fermentation of S. cerevisiae DWM-ZWF1-ACS1 resulted in 196.2 g/L xylitol concentration, 4.27 g/L h productivity and almost the theoretical yield. Expression of the two types of XR utilizing both NADPH and NADH is a promising strategy to meet the industrial demands for microbial xylitol production. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improving flavor metabolism of Saccharomyces cerevisiae by mixed culture with Bacillus licheniformis for Chinese Maotai-flavor liquor making.

Science.gov (United States)

Meng, Xing; Wu, Qun; Wang, Li; Wang, Diqiang; Chen, Liangqiang; Xu, Yan

2015-12-01

Microbial interactions could impact the metabolic behavior of microbes involved in food fermentation, and therefore they are important for improving food quality. This study investigated the effect of Bacillus licheniformis, the dominant bacteria in the fermentation process of Chinese Maotai-flavor liquor, on the metabolic activity of Saccharomyces cerevisiae. Results indicated that S. cerevisiae inhibited the growth of B. licheniformis in all mixed culture systems and final viable cell count was lower than 20 cfu/mL. Although growth of S. cerevisiae was barely influenced by B. licheniformis, its metabolism was changed as initial inoculation ratio varied. The maximum ethanol productions were observed in S. cerevisiae and B. licheniformis at 10(6):10(7) and 10(6):10(8) ratios and have increased by 16.8 % compared with single culture of S. cerevisiae. According to flavor compounds, the culture ratio 10(6):10(6) showed the highest level of total concentrations of all different kinds of flavor compounds. Correlation analyses showed that 12 flavor compounds, including 4 fatty acids and their 2 corresponding esters, 1 terpene, and 5 aromatic compounds, that could only be produced by S. cerevisiae were significantly correlated with the initial inoculation amount of B. licheniformis. These metabolic changes in S. cerevisiae were not only a benefit for liquor aroma, but may also be related to its inhibition effect in mixed culture. This study could help to reveal the microbial interactions in Chinese liquor fermentation and provide guidance for optimal arrangement of mixed culture fermentation systems.

Uranium removal from acidic aqueous solutions by Saccharomyces cerevisiae, Debaryomyces hansenii, Kluyveromyces marxianus and Candida colliculosa

International Nuclear Information System (INIS)

Sarri, S.; Misaelides, P.; Papanikolaou, M.; Zamboulis, D.

2009-01-01

The sorption of uranium from acidic aqueous solutions (pH 4.5, C init = 10 to 1000 mg U/L) by Saccharomyces cerevisiae, Debaryomyces hansenii, Kluyveromyces marxianus and Candida colliculosa was investigated using a batch technique. The U-sorption onto Saccharomyces cerevisiae and Debaryomyces hansenii followed a Langmuir, while that onto Kluyveromyces marxianus and Candida colliculosa a Freundlich isotherm. The results demonstrated that all investigated biomasses could effectively remove uranium from acidic aqueous solutions. From all sorbents, Saccharomyces cerevisiae appeared to be the most effective with a maximum sorption capacity of 127.7 mg U/g dry biomass. (author)

Osmo-, thermo- and ethanol- tolerances of Saccharomyces cerevisiae S1

Directory of Open Access Journals (Sweden)

Sandrasegarampillai Balakumar

2012-03-01

Full Text Available Saccharomyces cerevisiae S1, which is a locally isolated and improved strain showed viability at 40, 45 and 50ºC and produced ethanol at 40, 43 and 45ºC. When the cells were given heat shock at 45ºC for 30min and grown at 40ºC, 100% viability was observed for 60h, and addition of 200gl-1 ethanol has led to complete cell death at 30h. Heat shock given at 45ºC (for 30min has improved the tolerance to temperature induced ethanol shock leading to 37% viability at 30h. when the cells were subjected to ethanol (200gl-1 for 30 min and osmotic shock (sorbitol 300gl-1, trehalose contents in the cells were increased. The heat shocked cells showed better viability in presence of added ethanol. Soy flour supplementation has improved the viability of S. cerevisiae S1 to 80% in presence of 100gl-1 added ethanol and to 60% in presence of 300gl-1 sorbitol. In presence of sorbitol (200gl-1 and ethanol (50gl-1 at 40ºC, 46% viability was retained by S. cerevisiae S1 at 48h and it was improved to 80% by soy flour supplementation.

Integrative proteomics and biochemical analyses define Ptc6p as the Saccharomyces cerevisiae pyruvate dehydrogenase phosphatase.

Science.gov (United States)

Guo, Xiao; Niemi, Natalie M; Coon, Joshua J; Pagliarini, David J

2017-07-14

The pyruvate dehydrogenase complex (PDC) is the primary metabolic checkpoint connecting glycolysis and mitochondrial oxidative phosphorylation and is important for maintaining cellular and organismal glucose homeostasis. Phosphorylation of the PDC E1 subunit was identified as a key inhibitory modification in bovine tissue ∼50 years ago, and this regulatory process is now known to be conserved throughout evolution. Although Saccharomyces cerevisiae is a pervasive model organism for investigating cellular metabolism and its regulation by signaling processes, the phosphatase(s) responsible for activating the PDC in S. cerevisiae has not been conclusively defined. Here, using comparative mitochondrial phosphoproteomics, analyses of protein-protein interactions by affinity enrichment-mass spectrometry, and in vitro biochemistry, we define Ptc6p as the primary PDC phosphatase in S. cerevisiae Our analyses further suggest additional substrates for related S. cerevisiae phosphatases and describe the overall phosphoproteomic changes that accompany mitochondrial respiratory dysfunction. In summary, our quantitative proteomics and biochemical analyses have identified Ptc6p as the primary-and likely sole- S. cerevisiae PDC phosphatase, closing a key knowledge gap about the regulation of yeast mitochondrial metabolism. Our findings highlight the power of integrative omics and biochemical analyses for annotating the functions of poorly characterized signaling proteins. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Representações ideológicas no Twitter sobre a profissão-perigo professor: uma análise sob a perspectiva da ACD.

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Silvia Adelia Henrique Guimarães

2011-07-01

Full Text Available Objetivamos, neste trabalho, analisar alguns discursos sobre o professor no Twitter, perguntando, especificamente, como esta profissão é representada pelo prisma das situações práticas não idealizadas. A partir de uma notícia difundida na mídia sobre a agressão a uma professora em Porto Alegre, selecionamos noventa e um tweets para a investigação, buscando apoio teórico na Análise Crítica do Discurso (FAIRCLOUGH, 2003. Nesta microanálise, concentramo-nos no significado representacional, que corresponde aos modos de interação entre discurso e prática social (VAN LEEUWEN, 1997; THOMPSON, 2009. Os resultados gerais sugerem a uma naturalização e reprodução do discurso do professor como refém dos valores ideológicos que circulam na sociedade; b a ênfase dada ao aluno-agressor, que apesar de bastante criticado, parece receber autorização para suas ações. Desvelam uma cristalização da violência contra o professor, visto que a indignação implicada nos comentários não se seguiu de sugestões para mudanças, nem práticas, nem discursivas, contra este tipo de violência. Por fomentar reflexões sobre as representações ideológicas socialmente difundidas sobre a profissão professor, esta pesquisa pode revelar-se um apoio significativo para pesquisas em Linguística Aplicada, e também para outras áreas das Ciências Sociais, gerando avanço e sistematização dos achados.

Resgatando Processos geométricos da história da matemática para uma discussão sobre resolução de equações quadráticas

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Francisco Peregrino Rodrigues Neto

2001-06-01

Full Text Available O presente trabalho discute sobre álgebra, particularmente sobre equações quadráticas, fazendo uso da História da Matemática como recurso didático para ensinar os próprios conceitos de matemática. Objetivamente o trabalho resgata da História da Matemática alguns processos algébrico-geométricos, como auxílio didático para promover o ensino-aprendizagem dessa matéria através de atividades estruturadas com essa finalidade. O desenvolvimento da parte matemática se inicia com a resolução de casos particulares de equações do 2o grau e se completa com a dedução algébrica da conhecida fórmula de Bhãskara, usando-se recursos geométricos. O trabalho é dirigido para professores de matemática que atuam na 8o série do 1o grau e/ou no ensino médio.

Improving the Performance of the Granulosis Virus of Codling Moth (Lepidoptera: Tortricidae) by Adding the Yeast Saccharomyces cerevisiae with Sugar.

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Knight, Alan L; Basoalto, Esteban; Witzgall, Peter

2015-04-01

Studies were conducted with the codling moth granulosis virus (CpGV) to evaluate whether adding the yeast Saccharomyces cerevisiae Meyen ex E. C. Hansen with brown cane sugar could improve larval control of Cydia pomonella (L.). Larval mortalities in dipped-apple bioassays with S. cerevisiae or sugar alone were not significantly different from the water control. The addition of S. cerevisiae but not sugar with CpGV significantly increased larval mortality compared with CpGV alone. The combination of S. cerevisiae and sugar with CpGV significantly increased larval mortality compared with CpGV plus either additive alone. The addition of S. cerevisiae improved the efficacy of CpGV similarly to the use of the yeast Metschnikowia pulcherrima (isolated from field-collected larvae). The proportion of uninjured fruit in field trials was significantly increased with the addition of S. cerevisiae and sugar to CpGV compared with CpGV alone only in year 1, and from the controls in both years. In comparison, larval mortality was significantly increased in both years with the addition of S. cerevisiae and sugar with CpGV compared with CpGV alone or from the controls. The numbers of overwintering larvae on trees was significantly reduced from the control following a seasonal program of CpGV plus S. cerevisiae and sugar. The addition of a microencapsulated formulation of pear ester did not improve the performance of CpGV or CpGV plus S. cerevisiae and sugar. These data suggest that yeasts can enhance the effectiveness of the biological control agent CpGV, in managing and maintaining codling moth at low densities. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

Progress in terpene synthesis strategies through engineering of Saccharomyces cerevisiae.

Science.gov (United States)

Paramasivan, Kalaivani; Mutturi, Sarma

2017-12-01

Terpenes are natural products with a remarkable diversity in their chemical structures and they hold a significant market share commercially owing to their distinct applications. These potential molecules are usually derived from terrestrial plants, marine and microbial sources. In vitro production of terpenes using plant tissue culture and plant metabolic engineering, although receiving some success, the complexity in downstream processing because of the interference of phenolics and product commercialization due to regulations that are significant concerns. Industrial workhorses' viz., Escherichia coli and Saccharomyces cerevisiae have become microorganisms to produce non-native terpenes in order to address critical issues such as demand-supply imbalance, sustainability and commercial viability. S. cerevisiae enjoys several advantages for synthesizing non-native terpenes with the most significant being the compatibility for expressing cytochrome P450 enzymes from plant origin. Moreover, achievement of high titers such as 40 g/l of amorphadiene, a sesquiterpene, boosts commercial interest and encourages the researchers to envisage both molecular and process strategies for developing yeast cell factories to produce these compounds. This review contains a brief consideration of existing strategies to engineer S. cerevisiae toward the synthesis of terpene molecules. Some of the common targets for synthesis of terpenes in S. cerevisiae are as follows: overexpression of tHMG1, ERG20, upc2-1 in case of all classes of terpenes; repression of ERG9 by replacement of the native promoter with a repressive methionine promoter in case of mono-, di- and sesquiterpenes; overexpression of BTS1 in case of di- and tetraterpenes. Site-directed mutagenesis such as Upc2p (G888A) in case of all classes of terpenes, ERG20p (K197G) in case of monoterpenes, HMG2p (K6R) in case of mono-, di- and sesquiterpenes could be some generic targets. Efforts are made to consolidate various studies

Saccharomyces cerevisiae and non-Saccharomyces yeasts in grape varieties of the São Francisco Valley

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Camila M.P.B.S. de Ponzzes-Gomes

2014-06-01

Full Text Available The aims of this work was to characterise indigenous Saccharomyces cerevisiae strains in the naturally fermented juice of grape varieties Cabernet Sauvignon, Grenache, Tempranillo, Sauvignon Blanc and Verdejo used in the São Francisco River Valley, northeastern Brazil. In this study, 155 S. cerevisiae and 60 non-Saccharomyces yeasts were isolated and identified using physiological tests and sequencing of the D1/D2 domains of the large subunit of the rRNA gene. Among the non-Saccharomyces species, Rhodotorula mucilaginosa was the most common species, followed by Pichia kudriavzevii, Candida parapsilosis, Meyerozyma guilliermondii, Wickerhamomyces anomalus, Kloeckera apis, P. manshurica, C. orthopsilosis and C. zemplinina. The population counts of these yeasts ranged among 1.0 to 19 x 10(5 cfu/mL. A total of 155 isolates of S. cerevisiae were compared by mitochondrial DNA restriction analysis, and five molecular mitochondrial DNA restriction profiles were detected. Indigenous strains of S. cerevisiae isolated from grapes of the São Francisco Valley can be further tested as potential starters for wine production.

Adsorption and Interfacial Electron Transfer of Saccharomyces Cerevisiae

DEFF Research Database (Denmark)

Hansen, Allan Glargaard; Boisen, Anja; Nielsen, Jens Ulrik

2003-01-01

We have studied the adsorption and electron-transfer dynamics of Saccharomyces cerevisiae (yeast) iso-l-cytochrome c adsorbed on Au(lll) electrodes in aqueous phosphate buffer media. This cytochrome possesses a thiol group dos e to the protein surface (Cysl02) suitable for linking the protein...

Viabilidade celular de Saccharomyces cerevisiae cultivada em associação com bactérias contaminantes da fermentação alcoólica Cellular viability of Saccharomyces cerevisiae cultivated in association with contaminant bacteria of alcoholic fermentation

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Thais de Paula Nobre

2007-03-01

Full Text Available O objetivo deste trabalho foi estudar a influência de bactérias dos gêneros Bacillus e Lactobacillus, bem como de seus produtos metabólicos, na redução da viabilidade celular de leveduras Saccharomyces cerevisiae. As bactérias Bacillus subtilis, Bacillus coagulans, Bacillus stearothermophilus, Lactobacillus fermentum e Lactobacillus plantarum foram cultivadas em associação com a levedura S. cerevisiae (cepa Y-904 por 72 horas a 32 °C, sob agitação. A viabilidade celular, a taxa de brotamento e a população de células de S. cerevisiae e a acidez total, a acidez volátil e o pH dos meios de cultivos foram determinados às 0, 24, 48 e 72 horas do cultivo misto. As culturas de bactérias foram tratadas através do calor, de agente antimicrobiano e de irradiação. Os resultados mostraram que apenas os meios de cultivo mais acidificados, contaminados com as bactérias ativas L. fermentum e B. subtilis, provocaram redução na viabilidade celular de S. cerevisiae. Excetuando a bactéria B. subtilis tratada com radiação gama, as demais bactérias tratadas pelos diferentes processos (calor, irradiação e antimicrobiano não causaram diminuição da viabilidade celular e da população de S. cerevisiae, indicando que a presença isolada dos metabólitos celulares dessas bactérias não foi suficiente para reduzir a porcentagem de células vivas de S. cerevisiae.The aim of this project was to study the influence of the bacteria Bacillus and Lactobacillus, as well as their metabolic products to decrease the cellular viability of the yeast Saccharomyces cerevisiae. The bacteria Bacillus subtilis, Bacillus coagulans, Bacillus stearothermophilus, Lactobacillus fermentum and Lactobacillus plantarum were cultivated in association with yeast S. cerevisiae (strain Y-904 for 72 hours at 32 ºC under agitation. The cellular viability, budding rate and population of S. Cerevisiae and the total acidity, volatile acidity and pH of culture medium were

Division of labour in the yeast: Saccharomyces cerevisiae.

Science.gov (United States)

Wloch-Salamon, Dominika M; Fisher, Roberta M; Regenberg, Birgitte

2017-10-01

Division of labour between different specialized cell types is a central part of how we describe complexity in multicellular organisms. However, it is increasingly being recognized that division of labour also plays an important role in the lives of predominantly unicellular organisms. Saccharomyces cerevisiae displays several phenotypes that could be considered a division of labour, including quiescence, apoptosis and biofilm formation, but they have not been explicitly treated as such. We discuss each of these examples, using a definition of division of labour that involves phenotypic variation between cells within a population, cooperation between cells performing different tasks and maximization of the inclusive fitness of all cells involved. We then propose future research directions and possible experimental tests using S. cerevisiae as a model organism for understanding the genetic mechanisms and selective pressures that can lead to the evolution of the very first stages of a division of labour. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Energy-dependent effects of resveratrol in Saccharomyces cerevisiae.

Science.gov (United States)

Madrigal-Perez, Luis Alberto; Canizal-Garcia, Melina; González-Hernández, Juan Carlos; Reynoso-Camacho, Rosalia; Nava, Gerardo M; Ramos-Gomez, Minerva

2016-06-01

The metabolic effects induced by resveratrol have been associated mainly with the consumption of high-calorie diets; however, its effects with standard or low-calorie diets remain unclear. To better understand the interactions between resveratrol and cellular energy levels, we used Saccharomyces cerevisiae as a model. Herein it is shown that resveratrol: (a) decreased cell viability in an energy-dependent manner; (b) lessening of cell viability occurred specifically when cells were under cellular respiration; and (c) inhibition of oxygen consumption in state 4 occurred at low and standard energy levels, whereas at high energy levels oxygen consumption was promoted. These findings indicate that the effects of resveratrol are dependent on the cellular energy status and linked to metabolic respiration. Importantly, our study also revealed that S. cerevisiae is a suitable and useful model to elucidate the molecular targets of resveratrol under different nutritional statuses. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Selected non-Saccharomyces wine yeasts in controlled multistarter fermentations with Saccharomyces cerevisiae on alcoholic fermentation behaviour and wine aroma of cherry wines.

Science.gov (United States)

Sun, Shu Yang; Gong, Han Sheng; Jiang, Xiao Man; Zhao, Yu Ping

2014-12-01

This study examined the effect of mixed fermentation of non-Saccharomyces (Torulaspora delbrueckii ZYMAFLORE Alpha(TD n. Sacch) and Metschnikowia pulcherrima JS22) and Saccharomyces cerevisiae yeasts (D254 and EC1118) on the production of cherry wines, in comparison with commonly used mono-culture. Results obtained during AF demonstrated that negligible inhibitory effect was observed in S. cerevisiae/Alpha pair, whereas a strong antagonistic effect was detected between MJS22 and S. cerevisiae strain, resulting in an early death of MJS22. For volatile components determined, S. cerevisiae/MJS22 couple was found to significantly boost the production of most detected compounds, more particularly in higher alcohols, esters, acids and terpenes; while the characteristic of S. cerevisiae/Alpha pair is an increase in fruity esters, higher alcohols and decrease in acid production. Sensory evaluation revealed that S. cerevisiae/MJS22 pair reinforced sweet, green and fatty notes to the cherry wines, and S. cerevisiae/Alpha trial enhanced the fruity odour and reduced green note. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Mitochondria inheritance in yeast saccharomyces cerevisiae].

Science.gov (United States)

Fizikova, A Iu

2011-01-01

The review is devoted to the main mechanisms of mitochondria inheritance in yeast Saccharonmyces cerevisiae. The genetic mechanisms of functionally active mitochondria inheritance in eukaryotic cells is one of the most relevant in modem researches. A great number of genetic diseases are associated with mitochondria dysfunction. Plasticity of eukaryotic cell metabolism according to the environmental changes is ensured by adequate mitochondria functioning by means of ATP synthesis coordination, reactive oxygen species accumulation, apoptosis regulation and is an important factor of cell adaptation to stress. Mitochondria participation in important for cell vitality processes masters the presence of accurate mechanisms of mitochondria functions regulation according to environment fluctuations. The mechanisms of mitochondria division and distribution are highly conserved. Baker yeast S. cerevisiae is an ideal model object for mitochondria researches due to energetic metabolism lability, ability to switch over respiration to fermentation, and petite-positive phenotype. Correction of metabolism according to the environmental changes is necessary for cell vitality. The influence of respiratory, carbon, amino acid and phosphate metabolism on mitochondria functions was shown. As far as the mechanisms that stabilize functions of mitochondria and mtDNA are highly conserve, we can project yeast regularities on higher eukaryotes systems. This makes it possible to approximate understanding the etiology and pathogenesis of a great number of human diseases.

Functional expression of a heterologous nickel-dependent, ATP-independent urease in Saccharomyces cerevisiae.

Science.gov (United States)

Milne, N; Luttik, M A H; Cueto Rojas, H F; Wahl, A; van Maris, A J A; Pronk, J T; Daran, J M

2015-07-01

In microbial processes for production of proteins, biomass and nitrogen-containing commodity chemicals, ATP requirements for nitrogen assimilation affect product yields on the energy producing substrate. In Saccharomyces cerevisiae, a current host for heterologous protein production and potential platform for production of nitrogen-containing chemicals, uptake and assimilation of ammonium requires 1 ATP per incorporated NH3. Urea assimilation by this yeast is more energy efficient but still requires 0.5 ATP per NH3 produced. To decrease ATP costs for nitrogen assimilation, the S. cerevisiae gene encoding ATP-dependent urease (DUR1,2) was replaced by a Schizosaccharomyces pombe gene encoding ATP-independent urease (ure2), along with its accessory genes ureD, ureF and ureG. Since S. pombe ure2 is a Ni(2+)-dependent enzyme and Saccharomyces cerevisiae does not express native Ni(2+)-dependent enzymes, the S. pombe high-affinity nickel-transporter gene (nic1) was also expressed. Expression of the S. pombe genes into dur1,2Δ S. cerevisiae yielded an in vitro ATP-independent urease activity of 0.44±0.01 µmol min(-1) mg protein(-1) and restored growth on urea as sole nitrogen source. Functional expression of the Nic1 transporter was essential for growth on urea at low Ni(2+) concentrations. The maximum specific growth rates of the engineered strain on urea and ammonium were lower than those of a DUR1,2 reference strain. In glucose-limited chemostat cultures with urea as nitrogen source, the engineered strain exhibited an increased release of ammonia and reduced nitrogen content of the biomass. Our results indicate a new strategy for improving yeast-based production of nitrogen-containing chemicals and demonstrate that Ni(2+)-dependent enzymes can be functionally expressed in S. cerevisiae. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

COCOA (Theobroma cacao) Polyphenol-Rich Extract Increases the Chronological Lifespan of Saccharomyces cerevisiae.

Science.gov (United States)

Baiges, I; Arola, L

2016-01-01

BACKGROUND: Saccharomyces cerevisiae is a model organism with conserved aging pathways. Yeast chronological lifespan experiments mimic the processes involved in human non-dividing tissues, such as the nervous system or skeletal muscle, and can speed up the search for biomolecules with potential anti-aging effects before proceeding to animal studies. OBJECTIVE: To test the effectiveness of a cocoa polyphenol-rich extract (CPE) in expanding the S. cerevisiae chronological lifespan in two conditions: in the stationary phase reached after glucose depletion and under severe caloric restriction. MEASUREMENTS: Using a high-throughput method, wild-type S. cerevisiae and its mitochondrial manganese-dependent superoxide dismutase null mutant (sod2Δ) were cultured in synthetic complete dextrose medium. After 2 days, 0, 5 and 20 mg/ml of CPE were added, and viability was measured throughout the stationary phase. The effects of the major components of CPE were also evaluated. To determine yeast lifespan under severe caloric restriction conditions, cultures were washed with water 24 h after the addition of 0 and 20 mg/ml of CPE, and viability was followed over time. RESULTS : CPE increased the chronological lifespan of S. cerevisiae during the stationary phase in a dose-dependent manner. A similar increase was also observed in (sod2Δ). None of the major CPE components (theobromine, caffeine, maltodextrin, (-)-epicatechin, (+)-catechin and procyanidin B2) was able to increase the yeast lifespan. CPE further increased the yeast lifespan under severe caloric restriction. CONCLUSION: CPE increases the chronological lifespan of S. cerevisiae through a SOD2-independent mechanism. The extract also extends yeast lifespan under severe caloric restriction conditions. The high-throughput assay used makes it possible to simply and rapidly test the efficacy of a large number of compounds on yeast aging, requiring only small amounts, and is thus a convenient screening assay to accelerate

Comparative study of bio-ethanol production from mahula (Madhuca latifolia L.) flowers by Saccharomyces cerevisiae and Zymomonas mobilis

Energy Technology Data Exchange (ETDEWEB)

Behera, Shuvashish; Mohanty, Rama Chandra [Department of Botany, Utkal University, Vanivihar, Bhubaneswar 751004, Orissa (India); Ray, Ramesh Chandra [Microbiology Laboratory, Central Tuber Crops Research Institute (Regional Centre), Bhubaneswar 751019, Orissa (India)

2010-07-15

Mahula (Madhuca latifolia L.) flower is a suitable alternative cheaper carbohydrate source for production of bio-ethanol. Recent production of bio-ethanol by microbial fermentation as an alternative energy source has renewed research interest because of the increase in the fuel price. Saccharomyces cerevisiae (yeast) and Zymomonas mobilis (bacteria) are two most widely used microorganisms for ethanol production. In this study, experiments were carried out to compare the potential of the yeast S. cerevisiae (CTCRI strain) with the bacterium Z. mobilis (MTCC 92) for ethanol fermentation from mahula flowers. The ethanol production after 96 h fermentation was 149 and 122.9 g kg{sup -1} flowers using free cells of S. cerevisiae and Z. mobilis, respectively. The S. cerevisiae strain showed 21.2% more final ethanol production in comparison to Z. mobilis. Ethanol yield (Yx/s), volumetric product productivity (Qp), sugar to ethanol conversion rate (%) and microbial biomass concentration (X) obtained by S. cerevisiae were found to be 5.2%, 21.1%, 5.27% and 134% higher than Z. mobilis, respectively after 96 h of fermentation. (author)

Comparative study of bio-ethanol production from mahula (Madhuca latifolia L.) flowers by Saccharomyces cerevisiae and Zymomonas mobilis

International Nuclear Information System (INIS)

Behera, Shuvashish; Mohanty, Rama Chandra; Ray, Ramesh Chandra

2010-01-01

Mahula (Madhuca latifolia L.) flower is a suitable alternative cheaper carbohydrate source for production of bio-ethanol. Recent production of bio-ethanol by microbial fermentation as an alternative energy source has renewed research interest because of the increase in the fuel price. Saccharomyces cerevisiae (yeast) and Zymomonas mobilis (bacteria) are two most widely used microorganisms for ethanol production. In this study, experiments were carried out to compare the potential of the yeast S. cerevisiae (CTCRI strain) with the bacterium Z. mobilis (MTCC 92) for ethanol fermentation from mahula flowers. The ethanol production after 96 h fermentation was 149 and 122.9 g kg -1 flowers using free cells of S. cerevisiae and Z. mobilis, respectively. The S. cerevisiae strain showed 21.2% more final ethanol production in comparison to Z. mobilis. Ethanol yield (Yx/s), volumetric product productivity (Qp), sugar to ethanol conversion rate (%) and microbial biomass concentration (X) obtained by S. cerevisiae were found to be 5.2%, 21.1%, 5.27% and 134% higher than Z. mobilis, respectively after 96 h of fermentation. (author)

Horizontal and vertical growth of S. cerevisiae metabolic network.

KAUST Repository

Grassi, Luigi

2011-10-14

BACKGROUND: The growth and development of a biological organism is reflected by its metabolic network, the evolution of which relies on the essential gene duplication mechanism. There are two current views about the evolution of metabolic networks. The retrograde model hypothesizes that a pathway evolves by recruiting novel enzymes in a direction opposite to the metabolic flow. The patchwork model is instead based on the assumption that the evolution is based on the exploitation of broad-specificity enzymes capable of catalysing a variety of metabolic reactions. RESULTS: We analysed a well-studied unicellular eukaryotic organism, S. cerevisiae, and studied the effect of the removal of paralogous gene products on its metabolic network. Our results, obtained using different paralog and network definitions, show that, after an initial period when gene duplication was indeed instrumental in expanding the metabolic space, the latter reached an equilibrium and subsequent gene duplications were used as a source of more specialized enzymes rather than as a source of novel reactions. We also show that the switch between the two evolutionary strategies in S. cerevisiae can be dated to about 350 million years ago. CONCLUSIONS: Our data, obtained through a novel analysis methodology, strongly supports the hypothesis that the patchwork model better explains the more recent evolution of the S. cerevisiae metabolic network. Interestingly, the effects of a patchwork strategy acting before the Euascomycete-Hemiascomycete divergence are still detectable today.

Metabolic engineering of Saccharomyces cerevisiae for the production of n-butanol

Energy Technology Data Exchange (ETDEWEB)

Steen, EricJ.; Chan, Rossana; Prasad, Nilu; Myers, Samuel; Petzold, Christopher; Redding, Alyssa; Ouellet, Mario; Keasling, JayD.

2008-11-25

BackgroundIncreasing energy costs and environmental concerns have motivated engineering microbes for the production of ?second generation? biofuels that have better properties than ethanol.Results& ConclusionsSaccharomyces cerevisiae was engineered with an n-butanol biosynthetic pathway, in which isozymes from a number of different organisms (S. cerevisiae, Escherichia coli, Clostridium beijerinckii, and Ralstonia eutropha) were substituted for the Clostridial enzymes and their effect on n-butanol production was compared. By choosing the appropriate isozymes, we were able to improve production of n-butanol ten-fold to 2.5 mg/L. The most productive strains harbored the C. beijerinckii 3-hydroxybutyryl-CoA dehydrogenase, which uses NADH as a co-factor, rather than the R. eutropha isozyme, which uses NADPH, and the acetoacetyl-CoA transferase from S. cerevisiae or E. coli rather than that from R. eutropha. Surprisingly, expression of the genes encoding the butyryl-CoA dehydrogenase from C. beijerinckii (bcd and etfAB) did not improve butanol production significantly as previously reported in E. coli. Using metabolite analysis, we were able to determine which steps in the n-butanol biosynthetic pathway were the most problematic and ripe for future improvement.

Saccharomyces cerevisiae KNU5377 stress response during high-temperature ethanol fermentation.

Science.gov (United States)

Kim, Il-Sup; Kim, Young-Saeng; Kim, Hyun; Jin, Ingnyol; Yoon, Ho-Sung

2013-03-01

Fuel ethanol production is far more costly to produce than fossil fuels. There are a number of approaches to cost-effective fuel ethanol production from biomass. We characterized stress response of thermotolerant Saccharomyces cerevisiae KNU5377 during glucose-based batch fermentation at high temperature (40°C). S. cerevisiae KNU5377 (KNU5377) transcription factors (Hsf1, Msn2/4, and Yap1), metabolic enzymes (hexokinase, glyceraldehyde-3-phosphate dehydrogenase, glucose-6-phosphate dehydrogenase, isocitrate dehydrogenase, and alcohol dehydrogenase), antioxidant enzymes (thioredoxin 3, thioredoxin reductase, and porin), and molecular chaperones and its cofactors (Hsp104, Hsp82, Hsp60, Hsp42, Hsp30, Hsp26, Cpr1, Sti1, and Zpr1) are upregulated during fermentation, in comparison to S. cerevisiae S288C (S288C). Expression of glyceraldehyde-3-phosphate dehydrogenase increased significantly in KNU5377 cells. In addition, cellular hydroperoxide and protein oxidation, particularly lipid peroxidation of triosephosphate isomerase, was lower in KNU5377 than in S288C. Thus, KNU5377 activates various cell rescue proteins through transcription activators, improving tolerance and increasing alcohol yield by rapidly responding to fermentation stress through redox homeostasis and proteostasis.

Ecological interactions among Saccharomyces cerevisiae strains: insight into the dominance phenomenon.

Science.gov (United States)

Pérez-Torrado, Roberto; Rantsiou, Kalliopi; Perrone, Benedeta; Navarro-Tapia, Elisabeth; Querol, Amparo; Cocolin, Luca

2017-03-07

This study investigates the behaviour of Saccharomyces cerevisiae strains, in order to obtain insight into the intraspecies competition taking place in mixed populations of this species. Two strains of S. cerevisiae, one dominant and one non-dominant, were labelled and mixed, and individual fermentations were set up to study the transcriptomes of the strains by means of RNA-seq. The results obtained suggest that cell-to-cell contact and aggregation, which are driven by the expression of genes that are associated with the cell surface, are indispensable conditions for the achievement of dominance. Observations on mixed aggregates, made up of cells of both strains, which were detected by means of flow cytometry, have confirmed the transcriptomic data. Furthermore, overexpression of the SSU1 gene, which encodes for a transporter that confers resistance to sulphites, provides an ecological advantage to the dominant strain. A mechanistic model is proposed that sheds light on the dominance phenomenon between different strains of the S. cerevisiae species. The collected data suggest that cell-to-cell contact, together with differential sulphite production and resistance is important in determining the dominance of one strain over another.

The Response to Heat Shock and Oxidative Stress in Saccharomyces cerevisiae

Science.gov (United States)

Morano, Kevin A.; Grant, Chris M.; Moye-Rowley, W. Scott

2012-01-01

A common need for microbial cells is the ability to respond to potentially toxic environmental insults. Here we review the progress in understanding the response of the yeast Saccharomyces cerevisiae to two important environmental stresses: heat shock and oxidative stress. Both of these stresses are fundamental challenges that microbes of all types will experience. The study of these environmental stress responses in S. cerevisiae has illuminated many of the features now viewed as central to our understanding of eukaryotic cell biology. Transcriptional activation plays an important role in driving the multifaceted reaction to elevated temperature and levels of reactive oxygen species. Advances provided by the development of whole genome analyses have led to an appreciation of the global reorganization of gene expression and its integration between different stress regimens. While the precise nature of the signal eliciting the heat shock response remains elusive, recent progress in the understanding of induction of the oxidative stress response is summarized here. Although these stress conditions represent ancient challenges to S. cerevisiae and other microbes, much remains to be learned about the mechanisms dedicated to dealing with these environmental parameters. PMID:22209905

Perspectivas atuais sobre a sobrecarga do cuidador em saúde mental

Directory of Open Access Journals (Sweden)

Lucilene Cardoso

2012-04-01

Full Text Available Foi realizada uma revisão sistemática da literatura sobre sobrecarga de cuidadores em saúde mental. Os trabalhos foram selecionados na Biblioteca Virtual de Saúde (BVS, utilizando-se as palavras-chaves: sobrecarga do cuidador (caregiver burden. Os principais critérios para este estudo foram: artigos completos, publicados entre 2000 e 2010, nos idiomas português, inglês ou espanhol; indexados nas bases da BVS, que investigam a sobrecarga do cuidador em saúde mental, tendo cuidadores como assunto principal. Para análise foi considerado: o título, ano de publicação, objetivos, abordagem metodológica, instrumentos e principais resultados. A análise de 114 artigos na íntegra apontou como objetivos predominantes a sobrecarga entre os cuidadores informais e a validação de escalas psicométricas, destacando-se a Escala de Zarit. Alguns estudos apresentaram associação entre altos níveis de sobrecarga, ocorrência de sentimentos de culpa e sintomas depressivos. Em contrapartida indicaram intervenções psico-educacionais como positivas. Trata-se de uma temática com crescente interesse cientifico e necessidade de aprofundamento relacionado ao cuidador formal.

Yeast ratio is a critical factor for sequential fermentation of papaya wine by Williopsis saturnus and Saccharomyces cerevisiae.

Science.gov (United States)

Lee, Pin-Rou; Kho, Stephanie Hui Chern; Yu, Bin; Curran, Philip; Liu, Shao-Quan

2013-07-01

The growth kinetics and fermentation performance of Williopsis saturnus and Saccharomyces cerevisiae at ratios of 10:1, 1:1 and 1:10 (W.:S.) were studied in papaya juice with initial 7-day fermentation by W.saturnus, followed by S. cerevisiae. The growth kinetics of W. saturnus were similar at all ratios, but its maximum cell count decreased as the proportion of S. cerevisiae was increased. Conversely, there was an early death of S. cerevisiae at the ratio of 10:1. Williopsis saturnus was the dominant yeast at 10:1 ratio that produced papaya wine with elevated concentrations of acetate esters. On the other hand, 1:1 and 1:10 ratios allowed the coexistence of both yeasts which enabled the flavour-enhancing potential of W.saturnus as well as the ethyl ester and alcohol-producing abilities of S. cerevisiae. In particular, 1:1 and 1:10 ratios resulted in production of more ethyl esters, alcohols and 2-phenylethyl acetate. However, the persistence of both yeasts at 1:1 and 1:10 ratios led to formation of high levels of acetic acid. The findings suggest that yeast ratio is a critical factor for sequential fermentation of papaya wine by W.saturnus and S. cerevisiae as a strategy to modulate papaya wine flavour. © 2012 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Purification of Arp2/3 complex from Saccharomyces cerevisiae

Science.gov (United States)

Doolittle, Lynda K.; Rosen, Michael K.; Padrick, Shae B.

2014-01-01

Summary Much of cellular control over actin dynamics comes through regulation of actin filament initiation. At the molecular level, this is accomplished through a collection of cellular protein machines, called actin nucleation factors, which position actin monomers to initiate a new actin filament. The Arp2/3 complex is a principal actin nucleation factor used throughout the eukaryotic family tree. The budding yeast Saccharomyces cerevisiae has proven to be not only an excellent genetic platform for the study of the Arp2/3 complex, but also an excellent source for the purification of endogenous Arp2/3 complex. Here we describe a protocol for the preparation of endogenous Arp2/3 complex from wild type Saccharomyces cerevisiae. This protocol produces material suitable for biochemical study, and yields milligram quantities of purified Arp2/3 complex. PMID:23868593

The effect of medium structure complexity on the growth of Saccharomyces cerevisiae in gelatin-dextran systems.

Science.gov (United States)

Boons, Kathleen; Noriega, Estefanía; Verherstraeten, Niels; David, Charlotte C; Hofkens, Johan; Van Impe, Jan F

2015-04-16

As most food systems are (semi-)solid, the effect of food structure on bacterial growth has been widely acknowledged. However, studies on the growth dynamics of yeasts have neglected the effect of food structure. In this paper, the growth dynamics of the spoilage yeast Saccharomyces cerevisiae was investigated at 23.5 °C in broth, singular, homogeneous biopolymer systems and binary biopolymer systems with a heterogeneous microstructure. The biopolymers gelatin and dextran were used to introduce the different levels of structure. The metabolizing ability of gelatin and dextran by S. cerevisiae was examined. To study microbial behavior in the binary systems at the micro level, mixtures were imaged with confocal laser scanning microscopy (CLSM). Growth dynamics and microscopic images of S. cerevisiae were compared with those obtained for Escherichia coli in the same model system (Boons et al., 2014). Different phase-separated, heterogeneous microstructures were obtained by changing the amount of added gelatin and dextran. Regardless of the microstructure, S. cerevisiae was preferentially located in the dextran phase. Metabolizing ability-tests indicated that gelatin could be consumed by S. cerevisiae but in the presence of glucose, no change in gelatin concentration was observed. No indication of dextran metabolizing ability was observed. When supplementing broth with gelatin or dextran alone, an enhanced growth rate and maximum cell density were observed. This enhancement was further increased by adding a second biopolymer, introducing a heterogeneous microstructure and hence increasing the medium structure complexity. The results obtained indicate that food structure complexity plays a significant role in the growth dynamics of S. cerevisiae, an important food spoiler. Copyright © 2014. Published by Elsevier B.V.

Genomic structural variation contributes to phenotypic change of industrial bioethanol yeast Saccharomyces cerevisiae.

Science.gov (United States)

Zhang, Ke; Zhang, Li-Jie; Fang, Ya-Hong; Jin, Xin-Na; Qi, Lei; Wu, Xue-Chang; Zheng, Dao-Qiong

2016-03-01

Genomic structural variation (GSV) is a ubiquitous phenomenon observed in the genomes of Saccharomyces cerevisiae strains with different genetic backgrounds; however, the physiological and phenotypic effects of GSV are not well understood. Here, we first revealed the genetic characteristics of a widely used industrial S. cerevisiae strain, ZTW1, by whole genome sequencing. ZTW1 was identified as an aneuploidy strain and a large-scale GSV was observed in the ZTW1 genome compared with the genome of a diploid strain YJS329. These GSV events led to copy number variations (CNVs) in many chromosomal segments as well as one whole chromosome in the ZTW1 genome. Changes in the DNA dosage of certain functional genes directly affected their expression levels and the resultant ZTW1 phenotypes. Moreover, CNVs of large chromosomal regions triggered an aneuploidy stress in ZTW1. This stress decreased the proliferation ability and tolerance of ZTW1 to various stresses, while aneuploidy response stress may also provide some benefits to the fermentation performance of the yeast, including increased fermentation rates and decreased byproduct generation. This work reveals genomic characters of the bioethanol S. cerevisiae strain ZTW1 and suggests that GSV is an important kind of mutation that changes the traits of industrial S. cerevisiae strains. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Organization of Replication of Ribosomal DNA in Saccharomyces cerevisiae

NARCIS (Netherlands)

Linskens, Maarten H.K.; Huberman, Joel A.

1988-01-01

Using recently developed replicon mapping techniques, we have analyzed the replication of the ribosomal DNA in Saccharomyces cerevisiae. The results show that (i) the functional origin of replication colocalizes with an autonomously replicating sequence element previously mapped to the

Revisão técnica de livros sobre diagnósticos de enfermagem: percepções de enfermeiras do sul do Brasil

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Miriam de Abreu Almeida

2002-12-01

Full Text Available A temática desenvolvida no presente estudo aborda o relato de experiência de enfermeiras do sul do Brasil como revisoras técnicas de livros sobre diagnóstico de enfermagem. Busca-se contribuir com colegas que venham realizar tarefa semelhante lançando alguns aspectos para discussão. É situado o desenvolvimento do diagnóstico de enfermagem no Brasil. São identificadas as principais etapas de produção de livros traduzidos e citadas as atribuições de revisores técnicos. Comentam-se os pontos positivos e as dificuldades encontradas na atividade de revisão técnica. Sugerem-se alternativas para manter a qualidade final da obra e ampliar a oferta de textos especializados o mais fiel possível aos seus originais.

Uma revisão sobre instrumentos de rastreamento de violência doméstica contra o idoso

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Carlos Montes Paixão Jr.

Full Text Available Os dados sobre violência contra o idoso são escassos no Brasil. Para estudos adequados sobre a magnitude, fatores de risco e cuidados às vítimas, é necessária documentação sistemática e acurada. Este artigo revisou os instrumentos de rastreamento e avaliação de violência no idoso visando examinar o progresso no contexto internacional e brasileiro. Utilizando as bases de dados MEDLINE, PsycINFO, LILACS, CANE, OVIDs citations e livros de referência, realizou-se uma revisão sistemática da literatura para a seleção dos instrumentos. Fez-se, também, um escrutínio dos estudos de psicometria e utilização dos instrumentos, aplicando-se critérios para avaliar a qualidade dos estudos. Dos dezessete instrumentos encontrados, somente a Conflicts Tactics Scale foi adaptada para o Brasil, ainda que para uso em um grupo etário mais jovem. Alguns outros com boas características psicométricas também foram encontrados, como o Caregiver Abuse Screen, Elder Abuse Assessment Tool, Hwalek Sengstok Abuse Screening Test, Indicators of Abuse Screen, Qualcare scale e Vulnerability to Abuse Screening Scale. Ainda assim, de forma geral, há lacunas importantes nos processos de concepção, validação e adaptação desses instrumentos no Brasil e no exterior.

Bacterial xylose isomerases from the mammal gut Bacteroidetes cluster function in Saccharomyces cerevisiae for effective xylose fermentation.

Science.gov (United States)

Peng, Bingyin; Huang, Shuangcheng; Liu, Tingting; Geng, Anli

2015-05-17

Xylose isomerase (XI) catalyzes the conversion of xylose to xylulose, which is the key step for anaerobic ethanolic fermentation of xylose. Very few bacterial XIs can function actively in Saccharomyces cerevisiae. Here, we illustrate a group of XIs that would function for xylose fermentation in S. cerevisiae through phylogenetic analysis, recombinant yeast strain construction, and xylose fermentation. Phylogenetic analysis of deposited XI sequences showed that XI evolutionary relationship was highly consistent with the bacterial taxonomic orders and quite a few functional XIs in S. cerevisiae were clustered with XIs from mammal gut Bacteroidetes group. An XI from Bacteroides valgutus in this cluster was actively expressed in S. cerevisiae with an activity comparable to the fungal XI from Piromyces sp. Two XI genes were isolated from the environmental metagenome and they were clustered with XIs from environmental Bacteroidetes group. These two XIs could not be expressed in yeast with activity. With the XI from B. valgutus expressed in S. cerevisiae, background yeast strains were optimized by pentose metabolizing pathway enhancement and adaptive evolution in xylose medium. Afterwards, more XIs from the mammal gut Bacteroidetes group, including those from B. vulgatus, Tannerella sp. 6_1_58FAA_CT1, Paraprevotella xylaniphila and Alistipes sp. HGB5, were individually transformed into S. cerevisiae. The known functional XI from Orpinomyces sp. ukk1, a mammal gut fungus, was used as the control. All the resulting recombinant yeast strains were able to ferment xylose. The respiration-deficient strains harboring B. vulgatus and Alistipes sp. HGB5 XI genes respectively obtained specific xylose consumption rate of 0.662 and 0.704 g xylose gcdw(-1) h(-1), and ethanol specific productivity of 0.277 and 0.283 g ethanol gcdw(-1) h(-1), much comparable to those obtained by the control strain carrying Orpinomyces sp. ukk1 XI gene. This study demonstrated that XIs clustered in the

Glycerol positive promoters for tailored metabolic engineering of the yeast Saccharomyces cerevisiae.

Science.gov (United States)

Ho, Ping-Wei; Klein, Mathias; Futschik, Matthias; Nevoigt, Elke

2018-05-01

Glycerol offers several advantages as a substrate for biotechnological applications. An important step toward using the popular production host Saccharomyces cerevisiae for glycerol-based bioprocesses has been the fact that in recent studies commonly used S. cerevisiae strains were engineered to grow in synthetic medium containing glycerol as the sole carbon source. For metabolic engineering projects of S. cerevisiae growing on glycerol, characterized promoters are missing. In the current study, we used transcriptome analysis and a yECitrine-based fluorescence reporter assay to select and characterize 25 useful promoters. The promoters of the genes ALD4 and ADH2 showed 4.2-fold and 3-fold higher activities compared to the well-known strong TEF1 promoter. Moreover, the collection contains promoters with graded activities in synthetic glycerol medium and different degrees of glucose repression. To demonstrate the general applicability of the promoter collection, we successfully used a subset of the characterized promoters with graded activities in order to optimize growth on glycerol in an engineered derivative of CEN.PK, in which glycerol catabolism exclusively occurs via a non-native DHA pathway.

Growth-rate dependency of de novo resveratrol production in chemostat cultures of an engineered Saccharomyces cerevisiae strain

NARCIS (Netherlands)

Vos, T.; De la Torre Cortes, P.; Van Gulik, W.M.; Pronk, J.T.; Daran-Lapujade, P.A.S.

2015-01-01

Introduction: Saccharomyces cerevisiae has become a popular host for production of non-native compounds. The metabolic pathways involved generally require a net input of energy. To maximize the ATP yield on sugar in S. cerevisiae, industrial cultivation is typically performed in aerobic,

Sobre palavras e atos no consumo sustentável no Brasil: os ‘aparentes paradoxos’ de uma pesquisa qualitativa

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Rita de Cassia Monteiro Afonso

2013-07-01

Full Text Available Este artigo - recorte de uma pesquisa mais ampla denominada Choices Project: Leveraging Buying Power for Development – Ethical Consumption and Sustainable Procurement in Chile and Brazil - tem por objetivo “iluminar” alguns “aparentes paradoxos” encontrados nos discursos de entrevistados brasileiros em uma pesquisa qualitativa e analisar contradições no que se refere à discurso e prática sobre consumo sustentável. Por isso, o artigo apresenta o contexto político institucional brasileiro para o desenvolvimento sustentável com foco no consumo, as aparentes contradições encontradas na pesquisa e sua análise e conclui com os desafios que nos indicam aspectos para reflexão no estabelecimento de uma política de consumo consciente com parte de uma política mais ampla de desenvolvimento sustentável capaz de redesenhar o tecido urbano e assegurar prosperidade e qualidade de vida a todos.

Loss of lager specific genes and subtelomeric regions define two different Saccharomyces cerevisiae lineages for Saccharomyces pastorianus Group I and II strains.

Science.gov (United States)

Monerawela, Chandre; James, Tharappel C; Wolfe, Kenneth H; Bond, Ursula

2015-03-01

Lager yeasts, Saccharomyces pastorianus, are interspecies hybrids between S. cerevisiae and S. eubayanus and are classified into Group I and Group II clades. The genome of the Group II strain, Weihenstephan 34/70, contains eight so-called 'lager-specific' genes that are located in subtelomeric regions. We evaluated the origins of these genes through bioinformatic and PCR analyses of Saccharomyces genomes. We determined that four are of cerevisiae origin while four originate from S. eubayanus. The Group I yeasts contain all four S. eubayanus genes but individual strains contain only a subset of the cerevisiae genes. We identified S. cerevisiae strains that contain all four cerevisiae 'lager-specific' genes, and distinct patterns of loss of these genes in other strains. Analysis of the subtelomeric regions uncovered patterns of loss in different S. cerevisiae strains. We identify two classes of S. cerevisiae strains: ale yeasts (Foster O) and stout yeasts with patterns of 'lager-specific' genes and subtelomeric regions identical to Group I and II S. pastorianus yeasts, respectively. These findings lead us to propose that Group I and II S. pastorianus strains originate from separate hybridization events involving different S. cerevisiae lineages. Using the combined bioinformatic and PCR data, we describe a potential classification map for industrial yeasts. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.

Effects of dietary L-threonine and Saccharomyces cerevisiae on ...

African Journals Online (AJOL)

threonine (0, 2.5, 5 and 7.5 g/kg) with or without Saccharomyces cerevisiae (SC) on performance, carcass characteristics, intestinal morphology and immune system of broiler chickens. A total of 360 1-d-old male broiler chicks were randomly ...

Production of Saccharomyces cerevisiae biomass in papaya extract ...

African Journals Online (AJOL)

Extracts of papaya fruit were used as substrate for single cell protein (SCP) production using Saccharomyces cerevisiae. A 500 g of papaya fruit was extracted with different volumes of sterile distilled water. Extraction with 200 mL of sterile distilled water sustained highest cell growth. Biochemical analysis of dry biomass ...

Improved xylose and arabinose utilization by an industrial recombinant Saccharomyces cerevisiae strain using evolutionary engineering

DEFF Research Database (Denmark)

Sanchez, R.G.; Karhumaa, Kaisa; Fonseca, C.

2010-01-01

Background: Cost-effective fermentation of lignocellulosic hydrolysate to ethanol by Saccharomyces cerevisiae requires efficient mixed sugar utilization. Notably, the rate and yield of xylose and arabinose co-fermentation to ethanol must be enhanced. Results: Evolutionary engineering was used...... to improve the simultaneous conversion of xylose and arabinose to ethanol in a recombinant industrial Saccharomyces cerevisiae strain carrying the heterologous genes for xylose and arabinose utilization pathways integrated in the genome. The evolved strain TMB3130 displayed an increased consumption rate...... of our knowledge, this is the first report that characterizes the molecular mechanisms for improved mixed-pentose utilization obtained by evolutionary engineering of a recombinant S. cerevisiae strain. Increased transport of pentoses and increased activities of xylose converting enzymes contributed...

Behavior of Lactobacillus plantarum and Saccharomyces cerevisiae in fresh and thermally processed orange juice.

Science.gov (United States)

Alwazeer, Duried; Cachon, Remy; Divies, Charles

2002-10-01

Lactobacillus plantarum and Saccharomyces cerevisiae are acid-tolerant microorganisms that are able to spoil citrus juices before and after pasteurization. The growth of these microorganisms in orange juice with and without pasteurization was investigated. Two samples of orange juice were inoculated with ca. 10(5) CFU/ml of each microorganism. Others were inoculated with ca. 10(7) CFU/ml of each microorganism and then thermally treated. L. plantarum populations were reduced by 2.5 and 6 and 2 log10 CFU/ml, respectively. Samples of heated and nonheated juice were incubated at 15 degrees C for 20 days. Injured populations of L. plantarum decreased by ca. 2 log10 CFU/ml during the first 70 h of storage, but those of S. cerevisiae did not decrease. The length of the lag phase after pasteurization increased 6.2-fold for L. plantarum and 1.9-fold for S. cerevisiae, and generation times increased by 41 and 86%, respectively. The results of this study demonstrate the differences in the capabilities of intact and injured cells of spoilage microorganisms to spoil citrus juice and the different thermal resistance levels of cells. While L. plantarum was more resistant to heat treatment than S. cerevisiae was, growth recovery after pasteurization was faster for the latter microorganism.

Dos mares do Japão às Terras Brasileiras: Algumas considerações sobre o Brasil, a imigração japonesa e sua influência na agricultura

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Gil Vicente Nagai Lourenção

2015-07-01

Full Text Available Este artigo trata da presença japonesa na agricultura brasileirae oferece uma síntese da imigração japonesa e alguns númerosa respeito. Ele traz o contexto de inicio da imigração e interessesvinculados do ponto de vista brasileiro. Em segundo, apresentafatos notórios em relação a imigração. Em terceiro, traz informações sobre ascolônias pioneiras relacionando os locais e principais produções e, por fim, os projetos conjuntos desenvolvidos no Brasil com apoio do Japão. Em suma, trata-se de um pequenoresumo das principais colaborações e projetos realizados pelo Japão em território Brasileiro.

Globalização, desemprego e (nova pobreza: Estudo sobre impactes nas sociedades portuguesa e brasileira

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Cristina Albuquerque

2012-11-01

Full Text Available O presente artigo constitui‑se como um contributo para uma reflexão sobre possíveis conexões entre os processos de globalização económica, as mudanças no mercado de trabalho e os novos perfis da pobreza. O debate, enquadrado em dois contextos económicos distintos, o português (com ritmos de crescimento lentos e deficitários, com uma grave crise social e dificuldades de afirmação económica e política no contexto europeu e mundial e o brasileiro (com uma economia emergente e dinâmica, com fortes taxas de crescimento e uma tendência de redução nos índices de miséria e de pobreza, permite‑nos posicionar alguns dos impactes, económicos e sociais, decorrentes das pressões globais para a competitividade económica e potenciadores da emergência de novas formas de pobreza e de precarização social e laboral nas duas sociedades.

Expression of monellin in a food-grade delivery system in Saccharomyces cerevisiae.

Science.gov (United States)

Liu, Jun; Yan, Da-zhong; Zhao, Sheng-jun

2015-10-01

Genetically modified (GM) foods have caused much controversy. Construction of a food-grade delivery system is a desirable technique with presumptive impact on industrial applications from the perspective of bio-safety. The aim of this study was to construct a food-grade delivery system for Saccharomyces cerevisiae and to study the expression of monellin from the berries of the West African forest plant Dioscoreophyllum cumminsii in this system. A food-grade system for S. cerevisiae was constructed based on ribosomal DNA (rDNA)-mediated homologous recombination to enable high-copy-number integration of the expression cassette inserted into the rDNA locus. A copper resistance gene (CUP1) was used as the selection marker for yeast transformation. Because variants of transformants containing different copy numbers at the CUP1 locus can be readily selected after growth in the presence of elevated copper levels, we suggest that this system would prove useful in the generation of tandemly iterated gene clusters. Using this food-grade system, a single-chain monellin gene was heterologously expressed. The yield of monellin reached a maximum of 675 mg L(-1) . This system harbors exclusively S. cerevisiae DNA with no antibiotic resistance genes, and it should therefore be appropriate for safe use in the food industry. Monellin was shown to be expressed in this food-grade delivery system. To our knowledge, this is the first report so far on expression of monellin in a food-grade expression system in S. cerevisiae. © 2014 Society of Chemical Industry.

Transcriptome-Based Characterization of Interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus in Lactose-Grown Chemostat Cocultures

NARCIS (Netherlands)

Mendes, F.; Sieuwerts, S.; De Hulster, E.; Almering, M.J.; Luttik, M.A.; Pronk, J.T.; Smid, E.J.; Bron, P.A.; Daran-Lapujade, P.

2013-01-01

Mixed populations of Saccharomyces cerevisiae yeasts and lactic acid bacteria occur in many dairy, food, and beverage fermentations, but knowledge about their interactions is incomplete. In the present study, interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp.

Transcriptome-based characterization of interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus in lactose-grown chemostat cocultures

NARCIS (Netherlands)

Mendes, F.; Sieuwerts, S.; Hulster, de E.; Almering, M.J.; Luttik, M.A.H.; Pronk, J.T.; Smid, E.J.; Baron, P.A.; Daran-Lapujade, P.

2013-01-01

Mixed populations of Saccharomyces cerevisiae yeasts and lactic acid bacteria occur in many dairy, food, and beverage fermentations, but knowledge about their interactions is incomplete. In the present study, interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp.

Co-utilization of L-arabinose and D-xylose by laboratory and industrial Saccharomyces cerevisiae strains

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Boles Eckhard

2006-04-01

Full Text Available Abstract Background Fermentation of lignocellulosic biomass is an attractive alternative for the production of bioethanol. Traditionally, the yeast Saccharomyces cerevisiae is used in industrial ethanol fermentations. However, S. cerevisiae is naturally not able to ferment the pentose sugars D-xylose and L-arabinose, which are present in high amounts in lignocellulosic raw materials. Results We describe the engineering of laboratory and industrial S. cerevisiae strains to co-ferment the pentose sugars D-xylose and L-arabinose. Introduction of a fungal xylose and a bacterial arabinose pathway resulted in strains able to grow on both pentose sugars. Introduction of a xylose pathway into an arabinose-fermenting laboratory strain resulted in nearly complete conversion of arabinose into arabitol due to the L-arabinose reductase activity of the xylose reductase. The industrial strain displayed lower arabitol yield and increased ethanol yield from xylose and arabinose. Conclusion Our work demonstrates simultaneous co-utilization of xylose and arabinose in recombinant strains of S. cerevisiae. In addition, the co-utilization of arabinose together with xylose significantly reduced formation of the by-product xylitol, which contributed to improved ethanol production.

Aspergillus oryzae–Saccharomyces cerevisiae Consortium Allows Bio-Hybrid Fuel Cell to Run on Complex Carbohydrates

Science.gov (United States)

Jahnke, Justin P.; Hoyt, Thomas; LeFors, Hannah M.; Sumner, James J.; Mackie, David M.

2016-01-01

Consortia of Aspergillus oryzae and Saccharomyces cerevisiae are examined for their abilities to turn complex carbohydrates into ethanol. To understand the interactions between microorganisms in consortia, Fourier-transform infrared spectroscopy is used to follow the concentrations of various metabolites such as sugars (e.g., glucose, maltose), longer chain carbohydrates, and ethanol to optimize consortia conditions for the production of ethanol. It is shown that with proper design A. oryzae can digest food waste simulants into soluble sugars that S. cerevisiae can ferment into ethanol. Depending on the substrate and conditions used, concentrations of 13% ethanol were achieved in 10 days. It is further shown that a direct alcohol fuel cell (FC) can be coupled with these A. oryzae-enabled S. cerevisiae fermentations using a reverse osmosis membrane. This “bio-hybrid FC” continually extracted ethanol from an ongoing consortium, enhancing ethanol production and allowing the bio-hybrid FC to run for at least one week. Obtained bio-hybrid FC currents were comparable to those from pure ethanol—water mixtures, using the same FC. The A. oryzae–S. cerevisiae consortium, coupled to a bio-hybrid FC, converted food waste simulants into electricity without any pre- or post-processing. PMID:27681904

Improved ethanol production from whey Saccharomyces cerevisiae using permeabilized cells of Kluyveromyces marxianus

Energy Technology Data Exchange (ETDEWEB)

Rosenberg, M [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology; Tomaska, M [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology; Kanuch, J [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology; Sturdik, E [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology

1996-12-31

Permeabilized cells of Kluyveromyces marxianus CCY eSY2 were tested as the source of lactase in the ethanol fermentation of concentrated deproteinized whey (65-70 g/l lactose) by Saccharomyces cerevisiae CCY 10-13-14. Rapid lactose hydrolysis by small amounts of permeabilized cells following the fermentation of released glucose and galactose by S. cerevisiae resulted in a twofold enhancement of the overall volumetric productivity (1.03 g/lxh), compared to the fermentation in which the lactose was directly fermented by K. marxianus. (orig.)

Horizontal and vertical growth of S. cerevisiae metabolic network.

KAUST Repository

Grassi, Luigi; Tramontano, Anna

2011-01-01

of more specialized enzymes rather than as a source of novel reactions. We also show that the switch between the two evolutionary strategies in S. cerevisiae can be dated to about 350 million years ago. CONCLUSIONS: Our data, obtained through a novel

Reducing the genetic complexity of glycolysis in Saccharomyces cerevisiae

NARCIS (Netherlands)

Solis Escalante, D.

2015-01-01

Glycolysis, a biochemical pathway that oxidizes glucose to pyruvate, is at the core of sugar metabolism in Saccharomyces cerevisiae (bakers’ yeast). Glycolysis is not only a catabolic route involved in energy conservation, but also provides building blocks for anabolism. From an applied perspective,

Novel feeding strategies for Saccharomyces cerevisiae DS2155 ...

African Journals Online (AJOL)

The dual behavior of Saccharomyces cerevisiae on glucose feed as function of the dilution rate near the critical specific growth rate (ì=0.25) is a bottleneck in industrial production, hence the need for more efficient feeding strategies. In this work novel feeding strategies have been generated and evaluated. For each feeding ...

Evaluation of Saccharomyces cerevisiae as an antiaflatoxicogenic agent in broiler feedstuffs.

Science.gov (United States)

Pizzolitto, R P; Armando, M R; Salvano, M A; Dalcero, A M; Rosa, C A

2013-06-01

Aflatoxins (AF) are the most important mycotoxins produced by toxigenic strains of various Aspergillus spp. Biological decontamination of mycotoxins using microorganisms is a well-known strategy for the management of mycotoxins in feeds. Saccharomyces cerevisiae strains have been reported to bind aflatoxin B1 (AFB1). The aim of this study was to evaluate the ability of S. cerevisiae CECT 1891 in counteracting the deleterious effects of AFB1 in broiler chicks. Experimental aflatoxicosis was induced in 6-d-old broilers by feeding them 1.2 mg of AFB1/kg of feed for 3 wk, and the yeast strain was administrated in feed (10(10) cells/kg), in the drinking water (5 × 10(9) cells/L), or a combination of both treatments. A total of 160 chicks were randomly divided into 8 treatments (4 repetitions per treatment). Growth performance was measured weekly from d 7 to 28, and serum biochemical parameters, weights, and histopathological examination of livers were determined at d 28. The AFB1 significantly decreased the BW gain, feed intake, and impaired feed conversion rate. Moreover, AFB1 treatment decreased serum protein concentration and increased liver damage. The addition of S. cerevisiae strain to drinking water, to diets contaminated with AFB1, showed a positive protection effect on the relative weight of the liver, histopathology, and biochemical parameters. Furthermore, dietary addition of the yeast strain to drinking water alleviated the negative effects of AFB1 on growth performance parameters. In conclusion, this study suggests that in feed contaminated with AFB1, the use of S. cerevisiae is an alternative method to reduce the adverse effects of aflatoxicosis. Thus, apart from its excellent nutritional value, yeast can also be used as a mycotoxin adsorbent.

Estado e segurança alimentar: alcances e limitações de políticas públicas no Brasil

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Hirai, Wanda Griep

2007-01-01

Full Text Available Este texto reúne alguns elementos para ampliar a compreensão em relação às recentes discussões sobre a temática da segurança alimentar, que se tornou um desafio mundial desde a Declaração de Roma, em 1996. Procura-se apresentar breves aspectos conceituais e históricos, bem como a construção do conceito que se amplia ao incorporar elementos, além da noção de abastecimento que lhe deu origem. Por fim, apresentam-se alguns dados da última PNAD (2004 sobre segurança alimentar no Brasil, os quais apontam o impacto da insegurança alimentar, cuja expressão mais severa é a fome.

Saccharomyces cerevisiae: a sexy yeast with a prion problem.

Science.gov (United States)

Kelly, Amy C; Wickner, Reed B

2013-01-01

Yeast prions are infectious proteins that spread exclusively by mating. The frequency of prions in the wild therefore largely reflects the rate of spread by mating counterbalanced by prion growth slowing effects in the host. We recently showed that the frequency of outcross mating is about 1% of mitotic doublings with 23-46% of total matings being outcrosses. These findings imply that even the mildest forms of the [PSI+], [URE3] and [PIN+] prions impart > 1% growth/survival detriment on their hosts. Our estimate of outcrossing suggests that Saccharomyces cerevisiae is far more sexual than previously thought and would therefore be more responsive to the adaptive effects of natural selection compared with a strictly asexual yeast. Further, given its large effective population size, a growth/survival detriment of > 1% for yeast prions should strongly select against prion-infected strains in wild populations of Saccharomyces cerevisiae.

Therapeutic activity of a Saccharomyces cerevisiae-based probiotic and inactivated whole yeast on vaginal candidiasis.

Science.gov (United States)

Pericolini, Eva; Gabrielli, Elena; Ballet, Nathalie; Sabbatini, Samuele; Roselletti, Elena; Cayzeele Decherf, Amélie; Pélerin, Fanny; Luciano, Eugenio; Perito, Stefano; Jüsten, Peter; Vecchiarelli, Anna

2017-01-02

Vulvovaginal candidiasis is the most prevalent vaginal infection worldwide and Candida albicans is its major agent. Vulvovaginal candidiasis is characterized by disruption of the vaginal microbiota composition, as happens following large spectrum antibiotic usage. Recent studies support the effectiveness of oral and local probiotic treatment for prevention of recurrent vulvovaginal candidiasis. Saccharomyces cerevisiae is a safe yeast used as, or for, the production of ingredients for human nutrition and health. Here, we demonstrate that vaginal administration of probiotic Saccharomyces cerevisiae live yeast (GI) and, in part, inactivated whole yeast Saccharomyces cerevisiae (IY), used as post-challenge therapeutics, was able to positively influence the course of vaginal candidiasis by accelerating the clearance of the fungus. This effect was likely due to multiple interactions of Saccharomyces cerevisiae with Candida albicans. Both live and inactivated yeasts induced coaggregation of Candida and consequently inhibited its adherence to epithelial cells. However, only the probiotic yeast was able to suppress some major virulence factors of Candida albicans such as the ability to switch from yeast to mycelial form and the capacity to express several aspartyl proteases. The effectiveness of live yeast was higher than that of inactivated whole yeast suggesting that the synergy between mechanical effects and biological effects were dominant over purely mechanical effects. The protection of epithelial cells to Candida-induced damage was also observed. Overall, our data show for the first time that Saccharomyces cerevisiae-based ingredients, particularly the living cells, can exert beneficial therapeutic effects on a widespread vaginal mucosal infection.

An internal deletion in MTH1 enables growth on glucose of pyruvate-decarboxylase negative, non-fermentative Saccharomyces cerevisiae

NARCIS (Netherlands)

Oud, B.; Flores, C.L.; Gancedo, C.; Zhang, X.; Trueheart, J.; Daran, J.M.; Pronk, J.T.; Van Maris, A.J.A.

2012-01-01

Background Pyruvate-decarboxylase negative (Pdc-) strains of Saccharomyces cerevisiae combine the robustness and high glycolytic capacity of this yeast with the absence of alcoholic fermentation. This makes Pdc-S. cerevisiae an interesting platform for efficient conversion of glucose towards

Rekayasa Glukosa Dari Tandan Kosong Kelapa Sawit Melalui Proses Fermentasi Dengan Saccharomyces cerevisiae Menjadi Bioetanol

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Nasruddin Nasruddin

2013-06-01

Full Text Available This research aims to study the performance of Saccharomyces cerevisiae in glucose engineering into bioethanol. Glucose comes from palm oil empty fruit bunches that had been pretreated by delignification and fermentation. Glucose solution result from hydrolysis for each treatment of 500 ml was fermented with Saccharomyces cerevisiae (2, 4, 6 and 8 g, fermentation time (4, 6, 8 and 10 days. Result of fermentation was distilled at 75°C ± 5°C for 60 minutes. Bioethanol produced were tested including: specific gravity by using picnometer and acidity was tested by volumetric methods. The analysis showed that the best bioethanol produced in this experiment, followed by laboratory tests obtained from the interaction between treatments for time of hydrolysis by Aspergillus niger for 6 days, with 4 grams of Saccharomyces cerevisiae fermentation for 6 days. Based on the test results of bioethanol obtained density 0.9873 g/cm3, percentage of bioethanol 9.2889% (v/v and acid number value 1.820 mg/L.ABSTRAKPenelitian ini bertujuan untuk mempelajarai kinerja Saccharomyces cerevisiae  merekayasa glukosa menjadi bioetanol. Glukosa berasal dari tandan kosong kelapa sawit yang telah dilakukan pretreatment dengan cara delignifikasi dan fermentasi. Larutan glukosa hasil hidrolisis untuk masing-masing perlakuan sebanyak 500 mL difermentasi dengan S. cerevisiae (2; 4; 6 dan 8 g, waktu fermentasi (4; 6; 8 dan 10 hari. Hasil fermentasi didestilasi pada suhu 75oC ± 5oC selama 60 menit. Bioetanol yang dihasilkan diuji yang meliputi : berat jenis dengan mengunakan piknometer dan keasaman diuji dengan metode volumetri. Hasil analisis menunjukkan bioetanol yang terbaik berdasarkan hasil percobaan yang dilanjutkan dengan uji laboratorium didapatkan dari interaksi antar perlakuan untuk waktu hidrolisis dengan Aspergilus niger selama 6 hari, fermentasi dengan 4 gram Saccharomyces cerevisiae selama 6 hari. Berdasarkan hasil uji bioetanol untuk berat jenis 0,9873 g/cm3

Smart contracts sobre Bitcoin

OpenAIRE

Andreu Alemany, Josep Miquel

2016-01-01

El present treball final de màster realitza una introducció als smart contracts. El treball introdueix el concepte de contracte intel·ligent, els seus usos i alguns exemples existents. Seguidament proporciona les nocions necessàries de les transaccions del protocol Bitcoin per poder implementar un contracte intel·ligent, usant la blockchain que ofereix el protocol. Per últim, s'explica la implementació d'un contracte intel·ligent usant bitcoin: un canal de micropagaments. El presente traba...

Functional expression and evaluation of heterologous phosphoketolases in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Bergman, Alexandra; Siewers, Verena; Nielsen, Jens

2016-01-01

Phosphoketolases catalyze an energy-and redox-independent cleavage of certain sugar phosphates. Hereby, the two-carbon (C2) compound acetyl-phosphate is formed, which enzymatically can be converted into acetyl-CoA-a key precursor in central carbon metabolism. Saccharomyces cerevisiae does...... not demonstrate efficient phosphoketolase activity naturally. In this study, we aimed to compare and identify efficient heterologous phosphoketolase enzyme candidates that in yeast have the potential to reduce carbon loss compared to the native acetyl-CoA producing pathway by redirecting carbon flux directly from...... C5 and C6 sugars towards C2-synthesis. Nine phosphoketolase candidates were expressed in S. cerevisiae of which seven produced significant amounts of acetyl-phosphate after provision of sugar phosphate substrates in vitro. The candidates showed differing substrate specificities, and some...

Terminal acidic shock inhibits sour beer bottle conditioning by Saccharomyces cerevisiae.

Science.gov (United States)

Rogers, Cody M; Veatch, Devon; Covey, Adam; Staton, Caleb; Bochman, Matthew L

2016-08-01

During beer fermentation, the brewer's yeast Saccharomyces cerevisiae experiences a variety of shifting growth conditions, culminating in a low-oxygen, low-nutrient, high-ethanol, acidic environment. In beers that are bottle conditioned (i.e., carbonated in the bottle by supplying yeast with a small amount of sugar to metabolize into CO2), the S. cerevisiae cells must overcome these stressors to perform the ultimate act in beer production. However, medium shock caused by any of these variables can slow, stall, or even kill the yeast, resulting in production delays and economic losses. Here, we describe a medium shock caused by high lactic acid levels in an American sour beer, which we refer to as "terminal acidic shock". Yeast exposed to this shock failed to bottle condition the beer, though they remained viable. The effects of low pH/high [lactic acid] conditions on the growth of six different brewing strains of S. cerevisiae were characterized, and we developed a method to adapt the yeast to growth in acidic beer, enabling proper bottle conditioning. Our findings will aid in the production of sour-style beers, a trending category in the American craft beer scene. Copyright © 2016 Elsevier Ltd. All rights reserved.

Phenotypic evaluation and characterization of 21 industrial Saccharomyces cerevisiae yeast strains.

Science.gov (United States)

Kong, In Iok; Turner, Timothy Lee; Kim, Heejin; Kim, Soo Rin; Jin, Yong-Su

2018-02-01

Microorganisms have been studied and used extensively to produce value-added fuels and chemicals. Yeasts, specifically Saccharomyces cerevisiae, receive industrial attention because of their well-known ability to ferment glucose and produce ethanol. Thousands of natural or genetically modified S. cerevisiae have been found in industrial environments for various purposes. These industrial strains are isolated from industrial fermentation sites, and they are considered as potential host strains for superior fermentation processes. In many cases, industrial yeast strains have higher thermotolerance, increased resistances towards fermentation inhibitors and increased glucose fermentation rates under anaerobic conditions when compared with laboratory yeast strains. Despite the advantages of industrial strains, they are often not well characterized. Through screening and phenotypic characterization of commercially available industrial yeast strains, industrial fermentation processes requiring specific environmental conditions may be able to select an ideal starting yeast strain to be further engineered. Here, we have characterized and compared 21 industrial S. cerevisiae strains under multiple conditions, including their tolerance to varying pH conditions, resistance to fermentation inhibitors, sporulation efficiency and ability to ferment lignocellulosic sugars. These data may be useful for the selection of a parental strain for specific biotechnological applications of engineered yeast. © FEMS 2018. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Mead features fermented by Saccharomyces cerevisiae (lalvin k1 ...

African Journals Online (AJOL)

Eduardo Morales

Full Length Research Paper. Mead features fermented by Saccharomyces cerevisiae. (lalvin k1-1116). Eduardo Marin MORALES1*, Valmir Eduardo ALCARDE2 and Dejanira de Franceschi de. ANGELIS1. 1Department of Biochemistry and Microbiology, Institute of Biosciences, UNESP - Univ Estadual Paulista, Av. 24-A,.

Genetic Basis for Saccharomyces cerevisiae Biofilm in Liquid Medium

DEFF Research Database (Denmark)

Andersen, Kaj Scherz; Bojsen, Rasmus Kenneth; Gro Rejkjær Sørensen, Laura

2014-01-01

than free-living cells. We investigated the genetic basis for yeast, Saccharomyces cerevisiae, biofilm on solid surfaces in liquid medium by screening a comprehensive deletion mutant collection in the S1278b background and found 71 genes that were essential for biofilm development. Quantitative...

Parameter Optimization for Enhancement of Ethanol Yield by Atmospheric Pressure DBD-Treated Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Dong Xiaoyu; Yuan Yulian; Tang Qian; Dou Shaohua; Di Lanbo; Zhang Xiuling

2014-01-01

In this study, Saccharomyces cerevisiae (S. cerevisiae) was exposed to dielectric barrier discharge plasma (DBD) to improve its ethanol production capacity during fermentation. Response surface methodology (RSM) was used to optimize the discharge-associated parameters of DBD for the purpose of maximizing the ethanol yield achieved by DBD-treated S. cerevisiae. According to single factor experiments, a mathematical model was established using Box-Behnken central composite experiment design, with plasma exposure time, power supply voltage, and exposed-sample volume as impact factors and ethanol yield as the response. This was followed by response surface analysis. Optimal experimental parameters for plasma discharge-induced enhancement in ethanol yield were plasma exposure time of 1 min, power voltage of 26 V, and an exposed sample volume of 9 mL. Under these conditions, the resulting yield of ethanol was 0.48 g/g, representing an increase of 33% over control. (plasma technology)

Novel strategy to improve vanillin tolerance and ethanol fermentation performances of Saccharomycere cerevisiae strains.

Science.gov (United States)

Zheng, Dao-Qiong; Jin, Xin-Na; Zhang, Ke; Fang, Ya-Hong; Wu, Xue-Chang

2017-05-01

The aim of this work was to develop a novel strategy for improving the vanillin tolerance and ethanol fermentation performances of Saccharomyces cerevisiae strains. Isogeneic diploid, triploid, and tetraploid S. cerevisiae strains were generated by genome duplication of haploid strain CEN.PK2-1C. Ploidy increments improved vanillin tolerance and diminished proliferation capability. Antimitotic drug methyl benzimidazol-2-ylcarbamate (MBC) was used to introduce chromosomal aberrations into the tetraploid S. cerevisiae strain. Interestingly, aneuploid mutants with DNA contents between triploid and tetraploid were more resistant to vanillin and showed faster ethanol fermentation rates than all euploid strains. The physiological characteristics of these mutants suggest that higher bioconversion capacities of vanillin and ergosterol contents might contribute to improved vanillin tolerance. This study demonstrates that genome duplication and MBC treatment is a powerful strategy to improve the vanillin tolerance of yeast strains. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluation of Ethanol Production Activity by Engineered Saccharomyces cerevisiae Fermenting Cellobiose through the Phosphorolytic Pathway in Simultaneous Saccharification and Fermentation of Cellulose.

Science.gov (United States)

Lee, Won-Heong; Jin, Yong-Su

2017-09-28

In simultaneous saccharification and fermentation (SSF) for production of cellulosic biofuels, engineered Saccharomyces cerevisiae capable of fermenting cellobiose has provided several benefits, such as lower enzyme costs and faster fermentation rate compared with wild-type S. cerevisiae fermenting glucose. In this study, the effects of an alternative intracellular cellobiose utilization pathway-a phosphorolytic pathway based on a mutant cellodextrin transporter (CDT-1 (F213L)) and cellobiose phosphorylase (SdCBP)-was investigated by comparing with a hydrolytic pathway based on the same transporter and an intracellular β-glucosidase (GH1-1) for their SSF performances under various conditions. Whereas the phosphorolytic and hydrolytic cellobiose-fermenting S. cerevisiae strains performed similarly under the anoxic SSF conditions, the hydrolytic S. cerevisiae performed slightly better than the phosphorolytic S. cerevisiae under the microaerobic SSF conditions. Nonetheless, the phosphorolytic S. cerevisiae expressing the mutant CDT-1 showed better ethanol production than the glucose-fermenting S. cerevisiae with an extracellular β-glucosidase, regardless of SSF conditions. These results clearly prove that introduction of the intracellular cellobiose metabolic pathway into yeast can be effective on cellulosic ethanol production in SSF. They also demonstrate that enhancement of cellobiose transport activity in engineered yeast is the most important factor affecting the efficiency of SSF of cellulose.

Reflexões sobre uma nova historiografia literária na América LatinaDOI:10.5007/2175-8026.2010n59p113

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Eduardo Faria Coutinho

2010-03-01

Full Text Available Com a contribuição de correntes do pensamento como a Desconstrução, a Nova História e os chamados Estudos Culturais e Pós-Coloniais, a Historiografia Literária vem sofrendo, nas últimas décadas, considerável transformação, que se faz sentir pelo questionamento de alguns de seus pilares tradicionais, como as noções de “progressão linear”, “nação”, “idioma” e “literariedade”. Na América Latina, onde a historiografia literária sempre tomou por base os modelos europeus, e deixou de lado a produção de grande parte da população, como os indígenas e africanos, a questão vem inquietando diversos estudiosos, e já deu margem à criação de Histórias Literárias de alto teor inovativo, que dão voz a esses grupos, até então silenciados. Este trabalho consiste numa reflexão sobre esta nova historiografia literária na América Latina, e sobre o papel que ela vem desempenhando no campo dos estudos latino-americanos e de Literatura Comparada de maneira geral.

Directed evolution of pyruvate decarboxylase-negative Saccharomyces cerevisiae, yielding a C2-independent, glucose-tolerant, and pyruvate-hyperproducing yeast

NARCIS (Netherlands)

A.J. van Maris; J.M. Geertman; A. Vermeulen; M.K. Groothuizen; A.A. Winkler; M.D. Piper; J.P. van Dijken; J.T. Pronk

2004-01-01

textabstractThe absence of alcoholic fermentation makes pyruvate decarboxylase-negative (Pdc(-)) strains of Saccharomyces cerevisiae an interesting platform for further metabolic engineering of central metabolism. However, Pdc(-) S. cerevisiae strains have two growth defects:

Uma análise sobre transmasculinidades presentes numa série da mídia televisiva

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Thais Geraldo Oliveira de Aguiar

2018-02-01

Full Text Available Neste trabalho temos como objetivo analisar alguns significados sobre transmasculinidades presentes em dois episódios da série Liberdade de Gênero, exibida no canal de televisão brasileiro por assinatura GNT. Entendemos esta série como um potente artefato cultural para reflexão acerca das identidades trans, nela são apresentadas algumas histórias de pessoas que não se identificam com o gênero designado para elas ao nascerem, negando qualquer determinismo biológico. O preconceito, a exclusão social, a pressão religiosa e familiar que esses sujeitos vivenciam, no caso dos entrevistados, não venceram o desejo de ser quem sentiam ser. Nossos estudos têm como base os Estudos Culturais, na sua vertente pós-estruturalista, destacando o efeito das mídias na produção dos corpos e das sexualidades e também como produtora de saberes e conhecimentos, entendendo que os discursos veiculados pela mídia acionam efeitos de verdade e que essa proliferação de discursos vem atuando na produção dos sujeitos. A metodologia da pesquisa consiste na análise cultural, entendendo que esse tipo de análise é potente para pensar o quanto as pedagogias exercidas por estes artefatos são produtivas na constituição dos sujeitos e como vêm produzindo e reproduzindo significados acerca da transgeneridade, em específico sobre os homens trans.

Lycopene overproduction in Saccharomyces cerevisiae through combining pathway engineering with host engineering.

Science.gov (United States)

Chen, Yan; Xiao, Wenhai; Wang, Ying; Liu, Hong; Li, Xia; Yuan, Yingjin

2016-06-21

Microbial production of lycopene, a commercially and medically important compound, has received increasing concern in recent years. Saccharomyces cerevisiae is regarded as a safer host for lycopene production than Escherichia coli. However, to date, the lycopene yield (mg/g DCW) in S. cerevisiae was lower than that in E. coli and did not facilitate downstream extraction process, which might be attributed to the incompatibility between host cell and heterologous pathway. Therefore, to achieve lycopene overproduction in S. cerevisiae, both host cell and heterologous pathway should be delicately engineered. In this study, lycopene biosynthesis pathway was constructed by integration of CrtE, CrtB and CrtI in S. cerevisiae CEN.PK2. When YPL062W, a distant genetic locus, was deleted, little acetate was accumulated and approximately 100 % increase in cytosolic acetyl-CoA pool was achieved relative to that in parental strain. Through screening CrtE, CrtB and CrtI from diverse species, an optimal carotenogenic enzyme combination was obtained, and CrtI from Blakeslea trispora (BtCrtI) was found to have excellent performance on lycopene production as well as lycopene proportion in carotenoid. Then, the expression level of BtCrtI was fine-tuned and the effect of cell mating types was also evaluated. Finally, potential distant genetic targets (YJL064W, ROX1, and DOS2) were deleted and a stress-responsive transcription factor INO2 was also up-regulated. Through the above modifications between host cell and carotenogenic pathway, lycopene yield was increased by approximately 22-fold (from 2.43 to 54.63 mg/g DCW). Eventually, in fed-batch fermentation, lycopene production reached 55.56 mg/g DCW, which is the highest reported yield in yeasts. Saccharomyces cerevisiae was engineered to produce lycopene in this study. Through combining host engineering (distant genetic loci and cell mating types) with pathway engineering (enzyme screening and gene fine-tuning), lycopene yield was

Engineering of aromatic amino acid metabolism in Saccharomyces cerevisiae

NARCIS (Netherlands)

Vuralhan, Z.

2006-01-01

Saccharomyces cerevisiae is a popular industrial microorganism. It has since long been used in bread, beer and wine making. More recently it is also being applied for heterologous protein production and as a target organism for metabolic engineering. The work presented in this thesis describes how

Notas críticas sobre O Capital no século XXI de Thomas Piketty

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ROSA MARIA MARQUES

Full Text Available RESUMO Este artigo tem como objetivo analisar alguns aspectos do último livro de Thomas Piketty, O Capital no século XXI, do ponto de vista Marxista. São abordadas as relações que fundamentam sua análise de longo prazo da desigualdade na distribuição de renda e riqueza, seus conceitos de capital e de longo prazo, bem como sua interpretação do pensamento de Marx. Também são levantados alguns problemas existentes em sua base de dados. A análise tem como ponto de partida a crítica realizada por alguns autores Marxistas de renome, tais como Michel Husson, David Harvey e Yanis Varoufakis, bem como Robert Boyer. entre as conclusões do artigo, destaca-se o fato de o estudo de Piketty estar fracamente fundamentado teoricamente.

A apresentação de informações sobre o tráfego e a utilização de painéis de mensagem variável

Directory of Open Access Journals (Sweden)

Claudia Mont´Alvão

2010-04-01

Full Text Available

O presente artigo objetiva discutir alguns aspectos relacionados com a apresentação de informação sobre o tráfego, com a utilização de dispositivos utilizados pelas tecnologias de Sistemas Inteligentes de Transporte, como os painéis de mensagem variável. O foco da discussão está centrado nos aspectos de segurança do motorista durante a tarefa de dirigir. A utilização de disciplinas afins, como a Ergonomia, e as pesquisas realizadas nesta área são de grande valia, uma vez que nestas são discutidas as relações entre a informação necessária ao motorista e sua forma de apresentação, quando da sua utilização em sistemas como os painéis de mensagem. Finalmente, apontam-se áreas onde a pesquisa sobre os painéis pode ser continuada, uma vez que a qualidade da informação apresentada pode influir na tomada de informação por parte do usuário.

Engineering the fatty acid metabolic pathway in Saccharomyces cerevisiae for advanced biofuel production

Directory of Open Access Journals (Sweden)

Xiaoling Tang

2015-12-01

Full Text Available Fatty acid-derived fuels and chemicals have attracted a great deal of attention in recent decades, due to their following properties of high compatibility to gasoline-based fuels and existing infrastructure for their direct utilization, storage and distribution. The yeast Saccharomyces cerevisiae is the ideal biofuel producing candidate, based on the wealth of available genetic information and versatile tools designed to manipulate its metabolic pathways. Engineering the fatty acid metabolic pathways in S. cerevisiae is an effective strategy to increase its fatty acid biosynthesis and provide more pathway precursors for production of targeted products. This review summarizes the recent progress in metabolic engineering of yeast cells for fatty acids and fatty acid derivatives production, including the regulation of acetyl-CoA biosynthesis, NADPH production, fatty acid elongation, and the accumulation of activated precursors of fatty acids for converting enzymes. By introducing specific enzymes in the engineered strains, a powerful platform with a scalable, controllable and economic route for advanced biofuel production has been established. Keywords: Metabolic engineering, Fatty acid biosynthesis, Fatty acid derivatives, Saccharomyces cerevisiae

Influência de Alguns Fatores de Ambiente sobre os Escores de Conformação, Precocidade e Musculatura à Desmama em um Rebanho da Raça Nelore

Directory of Open Access Journals (Sweden)

Jorge Júnior João

2001-01-01

Full Text Available Dados de 23.251 animais da raça Nelore desmamados no período de 1994 a 1997, pertencentes à Agropecuária Jacarezinho Ltda., foram analisados para se avaliar os efeitos ambientais da idade da vaca, data de nascimento e idade à desmama sobre os escores visuais de conformação (C, precocidade (P e musculatura (M. Todos os efeitos estudados influenciaram significativamente os escores visuais. As análises indicaram que as vacas que pariram aos sete, oito e nove anos, obtiveram os melhores resultados para os escores visuais de C, P e M, assim como os animais que nasceram mais cedo dentro da estação de parição. Para a idade à desmama foi constatado que, quanto mais tarde o animal for desmamado, melhores serão seus escores. Os animais que desmamaram com 220 dias tiveram os melhores escores, enquanto os piores escores foram daqueles que desmamaram com 140 dias. Portanto, para se ter maior precisão na avaliação genética dos indivíduos jovens, fatores de correção para idade da vaca, data juliana de nascimento e idade à desmama devem ser utilizados sobre os escores de conformação, precocidade e musculatura.

Increasing cocoa butter-like lipid production of Saccharomyces cerevisiae by expression of selected cocoa genes

DEFF Research Database (Denmark)

Wei, Yongjun; Gossing, Michael; Bergenholm, David

2017-01-01

for CB biosynthesis from the cocoa genome using a phylogenetic analysis approach. By expressing the selected cocoa genes in S. cerevisiae, we successfully increased total fatty acid production, TAG production and CBL production in some S. cerevisiae strains. The relative CBL content in three yeast...... higher level of CBL compared with the control strain. In summary, CBL production by S. cerevisiae were increased through expressing selected cocoa genes potentially involved in CB biosynthesis.......Cocoa butter (CB) extracted from cocoa beans mainly consists of three different kinds of triacylglycerols (TAGs), 1,3-dipalmitoyl-2-oleoyl-glycerol (POP, C16:0-C18:1-C16:0), 1-palmitoyl-3-stearoyl-2-oleoyl-glycerol(POS,C16:0C18:1-C18:0) and 1,3-distearoyl-2-oleoyl-glycerol (SOS, C18:0-C18:1-C18...

Fermentation performance of engineered and evolved xylose-fermenting Saccharomyces cerevisiae strains

DEFF Research Database (Denmark)

Sonderegger, M.; Jeppsson, M.; Larsson, C.

2004-01-01

Lignocellulose hydrolysate is an abundant substrate for bioethanol production. The ideal microorganism for such a fermentation process should combine rapid and efficient conversion of the available carbon sources to ethanol with high tolerance to ethanol and to inhibitory components in the hydrol......Lignocellulose hydrolysate is an abundant substrate for bioethanol production. The ideal microorganism for such a fermentation process should combine rapid and efficient conversion of the available carbon sources to ethanol with high tolerance to ethanol and to inhibitory components...... in the hydrolysate. A particular biological problem are the pentoses, which are not naturally metabolized by the main industrial ethanol producer Saccharomyces cerevisiae. Several recombinant, mutated, and evolved xylose fermenting S. cerevisiae strains have been developed recently. We compare here the fermentation...

Response of Saccharomyces cerevisiae to cadmium stress

International Nuclear Information System (INIS)

Moreira, Luciana Mara Costa; Ribeiro, Frederico Haddad; Neves, Maria Jose; Porto, Barbara Abranches Araujo; Amaral, Angela M.; Menezes, Maria Angela B.C.; Rosa, Carlos Augusto

2009-01-01

The intensification of industrial activity has been greatly contributing with the increase of heavy metals in the environment. Among these heavy metals, cadmium becomes a serious pervasive environmental pollutant. The cadmium is a heavy metal with no biological function, very toxic and carcinogenic at low concentrations. The toxicity of cadmium and several other metals can be mainly attributed to the multiplicity of coordination complexes and clusters that they can form. Some aspects of the cellular response to cadmium were extensively investigated in the yeast Saccharomyces cerevisiae. The primary site of interaction between many toxic metals and microbial cells is the plasma membrane. Plasma-membrane permeabilisation has been reported in a variety of microorganisms following cadmium exposure, and is considered one mechanism of cadmium toxicity in the yeast. In this work, using the yeast strain S. cerevisiae W303-WT, we have investigated the relationships between Cd uptake and release of cellular metal ions (K + and Na + ) using neutron activation technique. The neutron activation was an easy, rapid and suitable technique for doing these metal determinations on yeast cells; was observed the change in morphology of the strains during the process of Cd accumulation, these alterations were observed by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) during incorporation of cadmium. (author)

Response of Saccharomyces cerevisiae to cadmium stress

Energy Technology Data Exchange (ETDEWEB)

Moreira, Luciana Mara Costa; Ribeiro, Frederico Haddad; Neves, Maria Jose [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Lab. de Radiobiologia], e-mail: luamatu@uol.com.br; Porto, Barbara Abranches Araujo; Amaral, Angela M.; Menezes, Maria Angela B.C. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Lab. de Ativacao Neutronica], e-mail: menezes@cdtn.br; Rosa, Carlos Augusto [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Microbiologia], e-mail: carlrosa@icb.ufmg

2009-07-01

The intensification of industrial activity has been greatly contributing with the increase of heavy metals in the environment. Among these heavy metals, cadmium becomes a serious pervasive environmental pollutant. The cadmium is a heavy metal with no biological function, very toxic and carcinogenic at low concentrations. The toxicity of cadmium and several other metals can be mainly attributed to the multiplicity of coordination complexes and clusters that they can form. Some aspects of the cellular response to cadmium were extensively investigated in the yeast Saccharomyces cerevisiae. The primary site of interaction between many toxic metals and microbial cells is the plasma membrane. Plasma-membrane permeabilisation has been reported in a variety of microorganisms following cadmium exposure, and is considered one mechanism of cadmium toxicity in the yeast. In this work, using the yeast strain S. cerevisiae W303-WT, we have investigated the relationships between Cd uptake and release of cellular metal ions (K{sup +} and Na{sup +}) using neutron activation technique. The neutron activation was an easy, rapid and suitable technique for doing these metal determinations on yeast cells; was observed the change in morphology of the strains during the process of Cd accumulation, these alterations were observed by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) during incorporation of cadmium. (author)

Propostas de Redução da Maioridade Penal: a Juventude Brasileira no Fio da Navalha?

OpenAIRE

Vavassori, Mariana Barreto; Toneli, Maria Juracy Filgueiras

2015-01-01

Resumo Este trabalho propõe uma reflexão teórica sobre o fenômeno da judicialização da vida, mais especificamente aquele que incide sobre os “adolescentes em conflito com a lei”, a partir das contribuições de Foucault e Derrida. O objetivo é dar visibilidade a alguns dos regimes de verdade sobre “adolescentes em conflito com a lei”, que emergem das/nas propostas de emendas constitucionais (PECs) sobre rebaixamento da idade penal, e seus efeitos de subjetivação. Utilizamos como operador metodo...

Festa de santo na cidade: notas sobre uma pesquisa etnográfica na periferia de Belém, Pará, Brasil

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Antonio Maurício Dias da Costa

Full Text Available O artigo faz alguns paralelos entre estudos que tratam da dimensão lúdica da religiosidade popular na Amazônia e os resultados de uma pesquisa etnográfica sobre uma festa de santo padroeiro em uma feira de bairro na Belém contemporânea. São observados elementos externos ao ritual religioso, como divulgação propagandística, trocas econômicas e usos políticos, que atuam como transformadores do sentido da devoção religiosa. Demonstra-se, com isso, a dinamicidade da reprodução da religiosidade popular, considerando a diversidade de manifestações festivas em diferentes realidades socioespaciais amazônicas. Devoção religiosa e 'razão prática' estão imbricadas no processo de modificação do evento pesquisado. Isto se revela pela complexidade das trocas sociais exercidas em uma festa de santo padroeiro na escala de uma grande cidade.

Real time, in situ observation of the photocatalytic inactivation of Saccharomyces cerevisiae cells

Energy Technology Data Exchange (ETDEWEB)

Zhang, Jingtao [School of Food and Bioengineering, Zhengzhou University of Light Industry, Zhengzhou 450002 (China); Environment Functional Materials Division, Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Wang, Xiaoxin [Environment Functional Materials Division, Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Li, Qi, E-mail: qili@imr.ac.cn [Environment Functional Materials Division, Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Shang, Jian Ku [Environment Functional Materials Division, Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

2015-04-01

An in situ microscopy technique was developed to observe in real time the photocatalytic inactivation process of Saccharomyces cerevisiae (S. cerevisiae) cells by palladium-modified nitrogen-doped titanium oxide (TiON/PdO) under visible light illumination. The technique was based on building a photocatalytic micro-reactor on the sample stage of a fluorescence/phase contrast microscopy capable of simultaneously providing the optical excitation to activate the photocatalyst in the micro-reactor and the illumination to acquire phase contrast images of the cells undergoing the photocatalytic inactivation process. Using TiON/PdO as an example, the technique revealed for the first time the vacuolar activities inside S. cerevisiae cells subjected to a visible light photocatalytic inactivation. The vacuoles responded to the photocatalytic attack by the first expansion of the vacuolar volume and then contraction, before the vacuole disappeared and the cell structure collapsed. Consistent with the aggregate behavior observed from the cell culture experiments, the transition in the vacuolar volume provided clear evidence that photocatalytic disinfection of S. cerevisiae cells started with an initiation period in which cells struggled to offset the photocatalytic damage and moved rapidly after the photocatalytic damage overwhelmed the defense mechanisms of the cells against oxidative attack. - Highlights: • Palladium-modified nitrogen-doped titanium oxidephotocatalyst (TiON/PdO) • Effective visible-light photocatalytic disinfection of yeast cells by TiON/PdO • Real time, in situ observation technique was developed for photocatalytic disinfection. • The fluorescence/phase contrast microscope with a photocatalytic micro-reactor • Yeast cell disinfection happened before the cell structure collapsed.

Reversão de ansiedade à matemática: alguns dados da literatura

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João dos Santos Carmo

2012-06-01

Full Text Available A ansiedade em relação à matemática é um fenômeno que compreende reações emocionais negativas diante de situações que requisitam o uso de conhecimentos matemáticos. É particularmente identificada no contexto escolar e está diretamente relacionada a experiências inadequadas de ensino dessa disciplina. O objetivo do presente artigo é fornecer um panorama atualizado da literatura que trata especificamente de um fenômeno chamado de ansiedade em relação à matemática. Inicialmente serão expostos a definição e os conceitos principais relacionados ao fenômeno em foco e, em seguida, alguns estudos acerca da reversão da ansiedade em relação à matemática. Por fim, serão apontadas algumas implicações para a pesquisa e para o desenvolvimento de programas brasileiros que visam ajudar indivíduos que apresentem ansiedade em relação à matemática.

Uma investigação sobre o ator consumidor na rede de pirataria e uma proposta de alternativa de estratégia de combate

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Ernesto Michelangelo Giglio

2009-08-01

Full Text Available O objetivo deste artigo é investigar as percepções e representações sociais do consumidor na rede de pirataria e propor uma alternativa de princípio estratégico de combate a esse comércio ilegal a partir de um modelo de rede que inclui o ator consumidor. A afirmativa básica é que a pirataria se organiza no formato de rede, onde o consumidor é um ator importante, que mantém a rede em razão de suas específicas percepções e representações sociais sobre o governo, sobre as empresas fabricantes, sobre os camelôs e sobre si próprio, percepções essas que abrangem mais do que o preço, que é o fator mais pesquisado no tema de pirataria. A base teórica de apoio é o conceito de rede social que existe como pano de fundo nas redes de negócios, com seus fatores de interdependência, comprometimento, expectativas e representações sociais, bem como o conceito de nó, que é a unidade de estudo das redes. Realizou-se uma pesquisa com grupos de adolescentes e adultos, e os dados mostraram a presença de representações sociais positivas sobre a ponta da pirataria, que é o camelô, e representações sociais negativas sobre o governo e as empresas que combatem a ilegalidade. Nas conclusões, mostra-se que há um ganho de compreensão quando se inclui o ator consumidor na rede, tanto no que se refere à manutenção do comércio pirata quanto às estratégias de combate. Como conclusão secundária importante, considerando os resultados abaixo do esperado por parte do governo no combate à pirataria, sugere-se um princípio estratégico a partir das redes sociais. A premissa da proposta é que só se combate uma rede a partir de outra rede, conforme atestam alguns exemplos de organizações sociais e comerciais.

Genome duplication and mutations in ACE2 cause multicellular, fast-sedimenting phenotypes in evolved Saccharomyces cerevisiae.

Science.gov (United States)

Oud, Bart; Guadalupe-Medina, Victor; Nijkamp, Jurgen F; de Ridder, Dick; Pronk, Jack T; van Maris, Antonius J A; Daran, Jean-Marc

2013-11-05

Laboratory evolution of the yeast Saccharomyces cerevisiae in bioreactor batch cultures yielded variants that grow as multicellular, fast-sedimenting clusters. Knowledge of the molecular basis of this phenomenon may contribute to the understanding of natural evolution of multicellularity and to manipulating cell sedimentation in laboratory and industrial applications of S. cerevisiae. Multicellular, fast-sedimenting lineages obtained from a haploid S. cerevisiae strain in two independent evolution experiments were analyzed by whole genome resequencing. The two evolved cell lines showed different frameshift mutations in a stretch of eight adenosines in ACE2, which encodes a transcriptional regulator involved in cell cycle control and mother-daughter cell separation. Introduction of the two ace2 mutant alleles into the haploid parental strain led to slow-sedimenting cell clusters that consisted of just a few cells, thus representing only a partial reconstruction of the evolved phenotype. In addition to single-nucleotide mutations, a whole-genome duplication event had occurred in both evolved multicellular strains. Construction of a diploid reference strain with two mutant ace2 alleles led to complete reconstruction of the multicellular-fast sedimenting phenotype. This study shows that whole-genome duplication and a frameshift mutation in ACE2 are sufficient to generate a fast-sedimenting, multicellular phenotype in S. cerevisiae. The nature of the ace2 mutations and their occurrence in two independent evolution experiments encompassing fewer than 500 generations of selective growth suggest that switching between unicellular and multicellular phenotypes may be relevant for competitiveness of S. cerevisiae in natural environments.

Lei Maria da Penha: novas abordagens sobre velhas propostas. Onde avançamos? = The Maria da Penha Law: new approaches on old propositions. Where did we move on?

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Pasinato, Wânia

2010-01-01

Full Text Available O objetivo deste artigo é refletir sobre os obstáculos e os problemas que têm sido enfrentados para a aplicação integral da Lei 11. 340/2006, a Lei Maria da Penha. As reflexões apresentadas utilizam os dados empíricos obtidos durante a realização da pesquisa sobre “Acesso à Justiça para Mulheres em Situação de Violência. Estudo Comparativo sobre as Delegacias da Mulher na América Latina (Brasil, Equador, Peru e Nicarágua”. A pesquisa foi realizada entre 2007 e 2009, em Belo Horizonte, e teve como núcleo de investigação entrevistas em profundidade com 15 mulheres que sofreram violência nas relações conjugais e procuraram a Delegacia da Mulher para registrar a ocorrência policial. Do conjunto de resultados obtidos, foram selecionados alguns dados e algumas reflexões que ajudam a ilustrar o cotidiano da aplicação da lei naquele município. Neste texto foram tomados para análise aspectos relacionados com o papel da polícia, do judiciário e da rede de serviços especializados no atendimento a mulheres em situação de violência. O objetivo é oferecer elementos para o debate em torno da aplicação da Lei Maria da Penha e contribuir para sua implementação integral

Capturing of the monoterpene olefin limonene produced in Saccharomyces cerevisiae

NARCIS (Netherlands)

Jongedijk, E.J.; Cankar, K.; Ranzijn, J.; Krol, van der A.R.; Bouwmeester, H.J.; Beekwilder, M.J.

2015-01-01

Monoterpene olefins such as limonene are plant compounds with applications as flavouring and fragrance agents, as solvents and potentially also in polymer and fuel chemistry. We engineered baker's yeast Saccharomyces cerevisiae to express a (-)-limonene synthase from Perilla frutescens and a

Dominance of Saccharomyces cerevisiae in alcoholic fermentation processes

DEFF Research Database (Denmark)

Albergaria, Helena; Arneborg, Nils

2016-01-01

Winemaking, brewing and baking are some of the oldest biotechnological processes. In all of them, alcoholic fermentation is the main biotransformation and Saccharomyces cerevisiae the primary microorganism. Although a wide variety of microbial species may participate in alcoholic fermentation and...

Evolutionary engineering of Saccharomyces cerevisiae for efficient aerobic xylose consumption

DEFF Research Database (Denmark)

Scalcinati, Gionata; Otero, José Manuel; Van Vleet, Jennifer R. H.

2012-01-01

Industrial biotechnology aims to develop robust microbial cell factories, such as Saccharomyces cerevisiae, to produce an array of added value chemicals presently dominated by petrochemical processes. Xylose is the second most abundant monosaccharide after glucose and the most prevalent pentose s...

Optimizing anaerobic growth rate and fermentation kinetics in Saccharomyces cerevisiae strains expressing Calvin-cycle enzymes for improved ethanol yield

NARCIS (Netherlands)

Papapetridis, I.; Goudriaan, M.; De Keijzer, Nikita A.; van den Broek, M.A.; van Maris, A.J.A.; Pronk, J.T.

2018-01-01

Background: Reduction or elimination of by-product formation is of immediate economic relevance in fermentation processes for industrial bioethanol production with the yeast Saccharomyces cerevisiae. Anaerobic cultures of wild-type S. cerevisiae require formation of glycerol to maintain the

The effects of Saccharomyces cerevisiae on the morphological and biomechanical characteristics of the tibiotarsus in broiler chickens

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B. Suzer

2017-12-01

Full Text Available The aim of this study is to examine the effects of different levels of the feed supplement Saccharomyces cerevisiae, a yeast metabolite, on broiler tibiotarsus traits and to reduce leg problems by identifying the pathological changes in leg skeletal system. Thus, reducing leg disorders due to the skeletal system, the cause of significant economic losses in our country (Turkey, was investigated by the supplementation of Saccharomyces cerevisiae in broiler feed. In the study, 300 male day-old, Ross 308 broiler chicks were used. Experiment groups were designed as follows: control; 0.1 % Saccharomyces cerevisiae; 0.2 % Saccharomyces cerevisiae; 0.4 % Saccharomyces cerevisiae. The experimental diets were chemically analyzed according to the methods of the Association of Official Analytical Chemists. Twelve groups were obtained, including three replicates for each experimental group. Each replicated group was comprised of 25 chicks, and thus 75 chicks were placed in each experimental group. After 42 days, broiler chickens were slaughtered. Tibiotarsi were weighed with a digital scale, and the lengths were measured with a digital caliper after the drying process. Cortical areas were measured with the ImageJ Image Processing and Analysis Program. A UTEST Model-7014 tension and compression machine and a Maxtest software were used to determine the bone strength of the tibiotarsus. The severity of the tibial dyschondroplasia lesion was evaluated as 0, +1, +2 and +3. Crude ash, calcium and phosphorus analyses were performed to determine the inorganic matter of tibiotarsi. For radiographic evaluations of epiphyseal growth plates, tibiotarsi from the right legs were photographed in lateral and craniocaudal positions and examined. Statistical analyses were performed with the SPSS statistics program. It was observed that the use of Saccharomyces cerevisiae as a feed supplement led to an increase in the bone traits of broiler chickens. Optimum

Comprehensive structural and substrate specificity classification of the Saccharomyces cerevisiae methyltransferome.

Science.gov (United States)

Wlodarski, Tomasz; Kutner, Jan; Towpik, Joanna; Knizewski, Lukasz; Rychlewski, Leszek; Kudlicki, Andrzej; Rowicka, Maga; Dziembowski, Andrzej; Ginalski, Krzysztof

2011-01-01

Methylation is one of the most common chemical modifications of biologically active molecules and it occurs in all life forms. Its functional role is very diverse and involves many essential cellular processes, such as signal transduction, transcriptional control, biosynthesis, and metabolism. Here, we provide further insight into the enzymatic methylation in S. cerevisiae by conducting a comprehensive structural and functional survey of all the methyltransferases encoded in its genome. Using distant homology detection and fold recognition, we found that the S. cerevisiae methyltransferome comprises 86 MTases (53 well-known and 33 putative with unknown substrate specificity). Structural classification of their catalytic domains shows that these enzymes may adopt nine different folds, the most common being the Rossmann-like. We also analyzed the domain architecture of these proteins and identified several new domain contexts. Interestingly, we found that the majority of MTase genes are periodically expressed during yeast metabolic cycle. This finding, together with calculated isoelectric point, fold assignment and cellular localization, was used to develop a novel approach for predicting substrate specificity. Using this approach, we predicted the general substrates for 24 of 33 putative MTases and confirmed these predictions experimentally in both cases tested. Finally, we show that, in S. cerevisiae, methylation is carried out by 34 RNA MTases, 32 protein MTases, eight small molecule MTases, three lipid MTases, and nine MTases with still unknown substrate specificity.

Comprehensive structural and substrate specificity classification of the Saccharomyces cerevisiae methyltransferome.

Directory of Open Access Journals (Sweden)

Tomasz Wlodarski

Full Text Available Methylation is one of the most common chemical modifications of biologically active molecules and it occurs in all life forms. Its functional role is very diverse and involves many essential cellular processes, such as signal transduction, transcriptional control, biosynthesis, and metabolism. Here, we provide further insight into the enzymatic methylation in S. cerevisiae by conducting a comprehensive structural and functional survey of all the methyltransferases encoded in its genome. Using distant homology detection and fold recognition, we found that the S. cerevisiae methyltransferome comprises 86 MTases (53 well-known and 33 putative with unknown substrate specificity. Structural classification of their catalytic domains shows that these enzymes may adopt nine different folds, the most common being the Rossmann-like. We also analyzed the domain architecture of these proteins and identified several new domain contexts. Interestingly, we found that the majority of MTase genes are periodically expressed during yeast metabolic cycle. This finding, together with calculated isoelectric point, fold assignment and cellular localization, was used to develop a novel approach for predicting substrate specificity. Using this approach, we predicted the general substrates for 24 of 33 putative MTases and confirmed these predictions experimentally in both cases tested. Finally, we show that, in S. cerevisiae, methylation is carried out by 34 RNA MTases, 32 protein MTases, eight small molecule MTases, three lipid MTases, and nine MTases with still unknown substrate specificity.

Switching the mode of sucrose utilization by Saccharomyces cerevisiae

OpenAIRE

Badotti, Fernanda; Dário, Marcelo G; Alves, Sergio L; Cordioli, Maria Luiza A; Miletti, Luiz C; de Araujo, Pedro S; Stambuk, Boris U

2008-01-01

Abstract Background Overflow metabolism is an undesirable characteristic of aerobic cultures of Saccharomyces cerevisiae during biomass-directed processes. It results from elevated sugar consumption rates that cause a high substrate conversion to ethanol and other bi-products, severely affecting cell physiology, bioprocess performance, and biomass yields. Fed-batch culture, where sucro...

Interactions between Drosophila and its natural yeast symbionts-Is Saccharomyces cerevisiae a good model for studying the fly-yeast relationship?

Science.gov (United States)

Hoang, Don; Kopp, Artyom; Chandler, James Angus

2015-01-01

Yeasts play an important role in the biology of the fruit fly, Drosophila melanogaster. In addition to being a valuable source of nutrition, yeasts affect D. melanogaster behavior and interact with the host immune system. Most experiments investigating the role of yeasts in D. melanogaster biology use the baker's yeast, Saccharomyces cerevisiae. However, S. cerevisiae is rarely found with natural populations of D. melanogaster or other Drosophila species. Moreover, the strain of S. cerevisiae used most often in D. melanogaster experiments is a commercially and industrially important strain that, to the best of our knowledge, was not isolated from flies. Since disrupting natural host-microbe interactions can have profound effects on host biology, the results from D. melanogaster-S. cerevisiae laboratory experiments may not be fully representative of host-microbe interactions in nature. In this study, we explore the D. melanogaster-yeast relationship using five different strains of yeast that were isolated from wild Drosophila populations. Ingested live yeasts have variable persistence in the D. melanogaster gastrointestinal tract. For example, Hanseniaspora occidentalis persists relative to S. cerevisiae, while Brettanomyces naardenensis is removed. Despite these differences in persistence relative to S. cerevisiae, we find that all yeasts decrease in total abundance over time. Reactive oxygen species (ROS) are an important component of the D. melanogaster anti-microbial response and can inhibit S. cerevisiae growth in the intestine. To determine if sensitivity to ROS explains the differences in yeast persistence, we measured yeast growth in the presence and absence of hydrogen peroxide. We find that B. naardenesis is completely inhibited by hydrogen peroxide, while H. occidentalis is not, which is consistent with yeast sensitivity to ROS affecting persistence within the D. melanogaster gastrointestinal tract. We also compared the feeding preference of D

Improving monoterpene geraniol production through geranyl diphosphate synthesis regulation in Saccharomyces cerevisiae.

Science.gov (United States)

Zhao, Jianzhi; Bao, Xiaoming; Li, Chen; Shen, Yu; Hou, Jin

2016-05-01

Monoterpenes have wide applications in the food, cosmetics, and medicine industries and have recently received increased attention as advanced biofuels. However, compared with sesquiterpenes, monoterpene production is still lagging in Saccharomyces cerevisiae. In this study, geraniol, a valuable acyclic monoterpene alcohol, was synthesized in S. cerevisiae. We evaluated three geraniol synthases in S. cerevisiae, and the geraniol synthase Valeriana officinalis (tVoGES), which lacked a plastid-targeting peptide, yielded the highest geraniol production. To improve geraniol production, synthesis of the precursor geranyl diphosphate (GPP) was regulated by comparing three specific GPP synthase genes derived from different plants and the endogenous farnesyl diphosphate synthase gene variants ERG20 (G) (ERG20 (K197G) ) and ERG20 (WW) (ERG20 (F96W-N127W) ), and controlling endogenous ERG20 expression, coupled with increasing the expression of the mevalonate pathway by co-overexpressing IDI1, tHMG1, and UPC2-1. The results showed that overexpressing ERG20 (WW) and strengthening the mevalonate pathway significantly improved geraniol production, while expressing heterologous GPP synthase genes or down-regulating endogenous ERG20 expression did not show positive effect. In addition, we constructed an Erg20p(F96W-N127W)-tVoGES fusion protein, and geraniol production reached 66.2 mg/L after optimizing the amino acid linker and the order of the proteins. The best strain yielded 293 mg/L geraniol in a fed-batch cultivation, a sevenfold improvement over the highest titer previously reported in an engineered S. cerevisiae strain. Finally, we showed that the toxicity of geraniol limited its production. The platform developed here can be readily used to synthesize other monoterpenes.

Bioprospecting and evolving alternative xylose and arabinose pathway enzymes for use in Saccharomyces cerevisiae.

Science.gov (United States)

Lee, Sun-Mi; Jellison, Taylor; Alper, Hal S

2016-03-01

Bioprospecting is an effective way to find novel enzymes from strains with desirable phenotypes. Such bioprospecting has enabled organisms such as Saccharomyces cerevisiae to utilize nonnative pentose sugars. Yet, the efficiency of this pentose catabolism (especially for the case of arabinose) remains suboptimal. Thus, further pathway optimization or identification of novel, optimal pathways is needed. Previously, we identified a novel set of xylan catabolic pathway enzymes from a superior pentose-utilizing strain of Ustilago bevomyces. These enzymes were used to successfully engineer a xylan-utilizing S. cerevisiae through a blended approach of bioprospecting and evolutionary engineering. Here, we expanded this approach to xylose and arabinose catabolic pathway engineering and demonstrated that bioprospected xylose and arabinose catabolic pathways from U. bevomyces offer alternative choices for enabling efficient pentose catabolism in S. cerevisiae. By introducing a novel set of xylose catabolic genes from U. bevomyces, growth rates were improved up to 85 % over a set of traditional Scheffersomyces stipitis pathway genes. In addition, we suggested an alternative arabinose catabolic pathway which, after directed evolution and pathway engineering, enabled S. cerevisiae to grow on arabinose as a sole carbon source in minimal medium with growth rates upwards of 0.05 h(-1). This pathway represents the most efficient growth of yeast on pure arabinose minimal medium. These pathways provide great starting points for further strain development and demonstrate the utility of bioprospecting from U. bevomyces.

Identification of novel GAPDH-derived antimicrobial peptides secreted by Saccharomyces cerevisiae and involved in wine microbial interactions

DEFF Research Database (Denmark)

Branco, Patrícia; Francisco, Diana; Chambon, Christophe

2014-01-01

Saccharomyces cerevisiae plays a primordial role in alcoholic fermentation and has a vast worldwide application in the production of fuel-ethanol, food and beverages. The dominance of S. cerevisiae over other microbial species during alcoholic fermentations has been traditionally ascribed to its ...

Improved Xylose Metabolism by a CYC8 Mutant of Saccharomyces cerevisiae.

Science.gov (United States)

Nijland, Jeroen G; Shin, Hyun Yong; Boender, Leonie G M; de Waal, Paul P; Klaassen, Paul; Driessen, Arnold J M

2017-06-01

Engineering Saccharomyces cerevisiae for the utilization of pentose sugars is an important goal for the production of second-generation bioethanol and biochemicals. However, S. cerevisiae lacks specific pentose transporters, and in the presence of glucose, pentoses enter the cell inefficiently via endogenous hexose transporters (HXTs). By means of in vivo engineering, we have developed a quadruple hexokinase deletion mutant of S. cerevisiae that evolved into a strain that efficiently utilizes d-xylose in the presence of high d-glucose concentrations. A genome sequence analysis revealed a mutation (Y353C) in the general corepressor CYC8 , or SSN6 , which was found to be responsible for the phenotype when introduced individually in the nonevolved strain. A transcriptome analysis revealed altered expression of 95 genes in total, including genes involved in (i) hexose transport, (ii) maltose metabolism, (iii) cell wall function (mannoprotein family), and (iv) unknown functions (seripauperin multigene family). Of the 18 known HXTs, genes for 9 were upregulated, especially the low or nonexpressed HXT10 , HXT13 , HXT15 , and HXT16 Mutant cells showed increased uptake rates of d-xylose in the presence of d-glucose, as well as elevated maximum rates of metabolism ( V max ) for both d-glucose and d-xylose transport. The data suggest that the increased expression of multiple hexose transporters renders d-xylose metabolism less sensitive to d-glucose inhibition due to an elevated transport rate of d-xylose into the cell. IMPORTANCE The yeast Saccharomyces cerevisiae is used for second-generation bioethanol formation. However, growth on xylose is limited by pentose transport through the endogenous hexose transporters (HXTs), as uptake is outcompeted by the preferred substrate, glucose. Mutant strains were obtained with improved growth characteristics on xylose in the presence of glucose, and the mutations mapped to the regulator Cyc8. The inactivation of Cyc8 caused increased

Advances in metabolic engineering of yeast Saccharomyces cerevisiae for production of chemicals.

Science.gov (United States)

Borodina, Irina; Nielsen, Jens

2014-05-01

Yeast Saccharomyces cerevisiae is an important industrial host for production of enzymes, pharmaceutical and nutraceutical ingredients and recently also commodity chemicals and biofuels. Here, we review the advances in modeling and synthetic biology tools and how these tools can speed up the development of yeast cell factories. We also present an overview of metabolic engineering strategies for developing yeast strains for production of polymer monomers: lactic, succinic, and cis,cis-muconic acids. S. cerevisiae has already firmly established itself as a cell factory in industrial biotechnology and the advances in yeast strain engineering will stimulate development of novel yeast-based processes for chemicals production. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Evidence against a photoprotective component of photoreactivation in Saccharomyces cerevisiae

International Nuclear Information System (INIS)

MacQuillan, A.M.; Green, G.; Perry, W.G.

1981-01-01

Photoreactivation-deficient (phr - ) mutants of Saccharomyces cerevisiae were shown to lack in vitro DNA-photolyase activity. A phr - mutant was then compared with a phr + strain for near-UV induced photoprotection from far-UV irradiation. Neither strain exhibited a photoprotective effect. (author)

The Plasma Membrane of Saccharomyces cerevisiae : Structure, Function, and Biogenesis

NARCIS (Netherlands)

VANDERREST, ME; KAMMINGA, AH; NAKANO, A; ANRAKU, Y; POOLMAN, B; KONINGS, WN

The composition of phospholipids, sphingolipids, and sterols in the plasma membrane has a strong influence on the activity of the proteins associated or embedded in the lipid bilayer. Since most lipid-synthesizing enzymes in Saccharomyces cerevisiae are located in intracellular organelles, an

Evaluation of Dose: Comparative Effect of Fast Neutrons and other Types of Radiation on the Survival of E. Coli and S. Cerevisiae; Evaluation de la Dose Delivree et Actions Comparees des Neutrons Rapides et d'Autres Radiations sur la Survie de E. Coli et S. Cerevisiae; Otsenka dozy i sravnitel'noe vliyanie bystrykh nejtronov i drugikh vidov izlucheniya na vyzhivaemost' E. Coli i S. Cerevisiae; Evaluacion de la Dosis Suministrada y Comparacion de la Accion de los Neutrones Rapidos sobre la Supervivencia del E. Coli y del S. Cerevisiae con la de Otras Radiaciones

Energy Technology Data Exchange (ETDEWEB)

Arnaud, Y.; Bocquet, C. [Centre d' Etudes Nucleaires de Saclay (France)

1964-05-15

diverses radiations dependent de l'organisme vivant etudie, du critere biologique choisi, mais aussi de la dose d'irradiation avec laquelle on fait la comparaison. L'efficacite biologique relative apparait dans ces experiences comme etant egalement une fonction de la dose. L'action des neutrons rapides et des rayons X releve souvent de processus radiobiologique differents. Il est arbitraire de relier entre elles les doses de ces diverses radiations par des relations lineaires. (author) [Spanish] Junto al reactor EL3 se encuentra un convertidor de uranio que permite obtener neutrones rapidos. Con una bateria de camaras de fision se mide el flujo y la distribucion espectral de los neutrones rapidos. Estos micro- detectores estan colocados en diversos puntos del volumen que se ha de irradiar y permiten evaluar experimentalmente la dosis absorbida en los tejidos. Gracias a este dispositivo y a este sistema de dosimetria, los autores han podido comparar la accion de los neutrones rapidos con las de otras radiaciones ionizantes (rayos X, rayos y) sobre organismos unicelulares. En este trabajo, estudian el porcentaje de supervivencia y la frecuencia de una mutacion morfologica en el Saccharomyces cerevisiae. Tambien han trazado la curva de supervivencia del Escherichia coli, expuesto a rayos X y a neutrones. La observacion de los resultados indica que los efectos biologicos relativos de estas diversas radiaciones dependen del organismo vivo estudiado, del criterio biologico elegido y, ademas, de la dosis de irradiacion con que se realiza la comparacion. Tambien se deduce de estos experimentos que la eficacia biologica relativa es funcion de la dosis. A menudo, la accion de los neutrones rapidos y de los rayos X depende de diferentes procesos radiobiologicos. Seria arbitrario establecer relaciones lineales entre las dosis de dichas radiaciones. (author) [Russian] Na reaktore EL-3 imeetsja uranovyj preobrazovatel, pozvoljajushhij poluchat' bystrye nejtrony. Batareja kamer delenija

Sensitivity to Lovastatin of Saccharomyces cerevisiae Strains Deleted for Pleiotropic Drug Resistance (PDR) Genes

DEFF Research Database (Denmark)

Formenti, Luca Riccardo; Kielland-Brandt, Morten

2011-01-01

The use of statins is well established in human therapy, and model organisms such as Saccharomyces cerevisiae are commonly used in studies of drug action at molecular and cellular levels. The investigation of the resistance mechanisms towards statins may suggest new approaches to improve therapy...... based on the use of statins. We investigated the susceptibility to lovastatin of S. cerevisiae strains deleted for PDR genes, responsible for exporting hydrophobic and amphi-philic drugs, such as lovastatin. Strains deleted for the genes tested, PDR1, PDR3, PDR5 and SNQ2, exhibited remarkably different...

Heat shock response improves heterologous protein secretion in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Hou, Jin; Österlund, Tobias; Liu, Zihe

2013-01-01

The yeast Saccharomyces cerevisiae is a widely used platform for the production of heterologous proteins of medical or industrial interest. However, heterologous protein productivity is often low due to limitations of the host strain. Heat shock response (HSR) is an inducible, global, cellular...... stress response, which facilitates the cell recovery from many forms of stress, e.g., heat stress. In S. cerevisiae, HSR is regulated mainly by the transcription factor heat shock factor (Hsf1p) and many of its targets are genes coding for molecular chaperones that promote protein folding and prevent...... the accumulation of mis-folded or aggregated proteins. In this work, we over-expressed a mutant HSF1 gene HSF1-R206S which can constitutively activate HSR, so the heat shock response was induced at different levels, and we studied the impact of HSR on heterologous protein secretion. We found that moderate and high...

Biosynthesis and engineering of kaempferol in Saccharomyces cerevisiae.

Science.gov (United States)

Duan, Lijin; Ding, Wentao; Liu, Xiaonan; Cheng, Xiaozhi; Cai, Jing; Hua, Erbing; Jiang, Huifeng

2017-09-26

Kaempferol is a flavonol with broad bioactivity of anti-oxidant, anti-cancer, anti-diabetic, anti-microbial, cardio-protective and anti-asthma. Microbial synthesis of kaempferol is a promising strategy because of the low content in primary plant source. In this study, the biosynthesis pathway of kaempferol was constructed in the budding yeast Saccharomyces cerevisiae to produce kaempferol de novo, and several biological measures were taken for high production. Firstly, a high efficient flavonol synthases (FLS) from Populus deltoides was introduced into the biosynthetic pathway of kaempferol. Secondly, a S. cerevisiae recombinant was constructed for de novo synthesis of kaempferol, which generated about 6.97 mg/L kaempferol from glucose. To further promote kaempferol production, the acetyl-CoA biosynthetic pathway was overexpressed and p-coumarate was supplied as substrate, which improved kaempferol titer by about 23 and 120%, respectively. Finally, a fed-batch process was developed for better kaempferol fermentation performance, and the production reached 66.29 mg/L in 40 h. The titer of kaempferol in our engineered yeast is 2.5 times of the highest reported titer. Our study provides a possible strategy to produce kaempferol using microbial cell factory.

Thermotolerant Kluyveromyces marxianus and Saccharomyces cerevisiae strains representing potentials for bioethanol production from Jerusalem artichoke by consolidated bioprocessing.

Science.gov (United States)

Hu, Nan; Yuan, Bo; Sun, Juan; Wang, Shi-An; Li, Fu-Li

2012-09-01

Thermotolerant inulin-utilizing yeast strains are desirable for ethanol production from Jerusalem artichoke tubers by consolidated bioprocessing (CBP). To obtain such strains, 21 naturally occurring yeast strains isolated by using an enrichment method and 65 previously isolated Saccharomyces cerevisiae strains were investigated in inulin utilization, extracellular inulinase activity, and ethanol fermentation from inulin and Jerusalem artichoke tuber flour at 40 °C. The strains Kluyveromyces marxianus PT-1 (CGMCC AS2.4515) and S. cerevisiae JZ1C (CGMCC AS2.3878) presented the highest extracellular inulinase activity and ethanol yield in this study. The highest ethanol concentration in Jerusalem artichoke tuber flour fermentation (200 g L(-1)) at 40 °C achieved by K. marxianus PT-1 and S. cerevisiae JZ1C was 73.6 and 65.2 g L(-1), which corresponded to the theoretical ethanol yield of 90.0 and 79.7 %, respectively. In the range of 30 to 40 °C, temperature did not have a significant effect on ethanol production for both strains. This study displayed the distinctive superiority of K. marxianus PT-1 and S. cerevisiae JZ1C in the thermotolerance and utilization of inulin-type oligosaccharides reserved in Jerusalem artichoke tubers. It is proposed that both K. marxianus and S. cerevisiae have considerable potential in ethanol production from Jerusalem artichoke tubers by a high temperature CBP.

Thermotolerant Kluyveromyces marxianus and Saccharomyces cerevisiae strains representing potentials for bioethanol production from Jerusalem artichoke by consolidated bioprocessing

Energy Technology Data Exchange (ETDEWEB)

Hu, Nan [Agricultural Univ., Qingdao, SD (China). College of Animal Science and Technology; Chinese Academy of Sciences, Qingdao, SD (China). Key Lab. of Biofuels; Yuan, Bo; Wang, Shi-An; Li, Fu-Li [Chinese Academy of Sciences, Qingdao, SD (China). Key Lab. of Biofuels; Sun, Juan [Agricultural Univ., Qingdao, SD (China). College of Animal Science and Technology

2012-09-15

Thermotolerant inulin-utilizing yeast strains are desirable for ethanol production from Jerusalem artichoke tubers by consolidated bioprocessing (CBP). To obtain such strains, 21 naturally occurring yeast strains isolated by using an enrichment method and 65 previously isolated Saccharomyces cerevisiae strains were investigated in inulin utilization, extracellular inulinase activity, and ethanol fermentation from inulin and Jerusalem artichoke tuber flour at 40 C. The strains Kluyveromyces marxianus PT-1 (CGMCC AS2.4515) and S. cerevisiae JZ1C (CGMCC AS2.3878) presented the highest extracellular inulinase activity and ethanol yield in this study. The highest ethanol concentration in Jerusalem artichoke tuber flour fermentation (200 g L{sup -1}) at 40 C achieved by K. marxianus PT-1 and S. cerevisiae JZ1C was 73.6 and 65.2 g L{sup -1}, which corresponded to the theoretical ethanol yield of 90.0 and 79.7 %, respectively. In the range of 30 to 40 C, temperature did not have a significant effect on ethanol production for both strains. This study displayed the distinctive superiority of K. marxianus PT-1 and S. cerevisiae JZ1C in the thermotolerance and utilization of inulin-type oligosaccharides reserved in Jerusalem artichoke tubers. It is proposed that both K. marxianus and S. cerevisiae have considerable potential in ethanol production from Jerusalem artichoke tubers by a high temperature CBP. (orig.)

Identification and characterization of antifungal compounds using a Saccharomyces cerevisiae reporter bioassay.

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Brad Tebbets

Full Text Available New antifungal drugs are urgently needed due to the currently limited selection, the emergence of drug resistance, and the toxicity of several commonly used drugs. To identify drug leads, we screened small molecules using a Saccharomyces cerevisiae reporter bioassay in which S. cerevisiae heterologously expresses Hik1, a group III hybrid histidine kinase (HHK from Magnaporthe grisea. Group III HHKs are integral in fungal cell physiology, and highly conserved throughout this kingdom; they are absent in mammals, making them an attractive drug target. Our screen identified compounds 13 and 33, which showed robust activity against numerous fungal genera including Candida spp., Cryptococcus spp. and molds such as Aspergillus fumigatus and Rhizopus oryzae. Drug-resistant Candida albicans from patients were also highly susceptible to compounds 13 and 33. While the compounds do not act directly on HHKs, microarray analysis showed that compound 13 induced transcripts associated with oxidative stress, and compound 33, transcripts linked with heavy metal stress. Both compounds were highly active against C. albicans biofilm, in vitro and in vivo, and exerted synergy with fluconazole, which was inactive alone. Thus, we identified potent, broad-spectrum antifungal drug leads from a small molecule screen using a high-throughput, S. cerevisiae reporter bioassay.

Comparative proteomics analysis of engineered Saccharomyces cerevisiae with enhanced biofuel precursor production.

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Xiaoling Tang

Full Text Available The yeast Saccharomyces cerevisiae was metabolically modified for enhanced biofuel precursor production by knocking out genes encoding mitochondrial isocitrate dehydrogenase and over-expression of a heterologous ATP-citrate lyase. A comparative iTRAQ-coupled 2D LC-MS/MS analysis was performed to obtain a global overview of ubiquitous protein expression changes in S. cerevisiae engineered strains. More than 300 proteins were identified. Among these proteins, 37 were found differentially expressed in engineered strains and they were classified into specific categories based on their enzyme functions. Most of the proteins involved in glycolytic and pyruvate branch-point pathways were found to be up-regulated and the proteins involved in respiration and glyoxylate pathway were however found to be down-regulated in engineered strains. Moreover, the metabolic modification of S. cerevisiae cells resulted in a number of up-regulated proteins involved in stress response and differentially expressed proteins involved in amino acid metabolism and protein biosynthesis pathways. These LC-MS/MS based proteomics analysis results not only offered extensive information in identifying potential protein-protein interactions, signal pathways and ubiquitous cellular changes elicited by the engineered pathways, but also provided a meaningful biological information platform serving further modification of yeast cells for enhanced biofuel production.

Role of hexose transport in control of glycolytic flux in Saccharomyces cerevisiae.

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Elbing, Karin; Larsson, Christer; Bill, Roslyn M; Albers, Eva; Snoep, Jacky L; Boles, Eckhard; Hohmann, Stefan; Gustafsson, Lena

2004-09-01

The yeast Saccharomyces cerevisiae predominantly ferments glucose to ethanol at high external glucose concentrations, irrespective of the presence of oxygen. In contrast, at low external glucose concentrations and in the presence of oxygen, as in a glucose-limited chemostat, no ethanol is produced. The importance of the external glucose concentration suggests a central role for the affinity and maximal transport rates of yeast's glucose transporters in the control of ethanol production. Here we present a series of strains producing functional chimeras between the hexose transporters Hxt1 and Hxt7, each of which has distinct glucose transport characteristics. The strains display a range of decreasing glycolytic rates resulting in a proportional decrease in ethanol production. Using these strains, we show for the first time that at high glucose levels, the glucose uptake capacity of wild-type S. cerevisiae does not control glycolytic flux during exponential batch growth. In contrast, our chimeric Hxt transporters control the rate of glycolysis to a high degree. Strains whose glucose uptake is mediated by these chimeric transporters will undoubtedly provide a powerful tool with which to examine in detail the mechanism underlying the switch between fermentation and respiration in S. cerevisiae and will provide new tools for the control of industrial fermentations.

Protein expression of saccharomyces cerevisiae in response to uranium exposure

International Nuclear Information System (INIS)

Sakamoto, Fuminori; Nankawa, Takuya; Kozai, Naofumi; Ohnuki, Toshihiko; Fujii, Tsutomu; Iefuji, Haruyuki; Francis, A.J.

2007-01-01

Protein expression of Saccharomyces cerevisiae grown in the medium containing 238 U (VI) and 233 U (VI) was examined by two-dimensional gel electrophoresis. Saccharomyces cerevisiae of BY4743 was grown in yeast nitrogen base medium containing glucose and glycerol 2-phosphate and 238 U of 0, 2.0, and 5.0 x 10 -4 M or 233 U of 2.5 x 10 -6 M (radioactivity was higher by 350 times than 2.0 x 10 -4 M 238 U) and 5.0 x 10 -6 M for 112 h at 30 degC. The growth of Saccharomyces cerevisiae was monitored by measuring OD 600 at 112 h after the inoculation. Uranium concentrations in the media also were measured by radiometry using a liquid scintillation counter. The growths of the yeast grown in the above media were in the following order: control>2.5 x 10 -6 M 233 U>2.0 x 10 -4 M 238 U>5.0 x 10 -6 M 233 U>5.0 x 10 -4 M 238 U. This result indicated that not only radiological but also chemical effect of U reduced the growth of the yeast. The concentrations of U in the medium containing 238 U or 233 U decreased, suggesting U accumulation by the yeast cells. The 2-D gel electrophoresis analysis showed the appearance of several spots after exposure to 238 U or to 233 U but not in the control containing no uranium. These results show that the yeast cells exposed to U express several specific proteins. (author)

Removal of Pyrimethanil and Fenhexamid from Saccharomyces cerevisiae Liquid Cultures

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Etjen Bizaj

2011-01-01

Full Text Available The capacity for the removal of pyrimethanil and fenhexamid, two fungicides commonly used for the control of Botrytis cinerea in vineyards, has been evaluated during an alcoholic fermentation process in batch system. Commercial and wild strains of Saccharomyces cerevisiae were used. Batch fermentations were carried out in yeast extract-malt extract medium (YM with 18.0 % (by mass glucose, and the fungicides were added separately at three concentrations: 0.1, 1.0 and 10.0 mg/L. The removal capacity of yeast strains was also examined in stationary phase cultures of Saccharomyces cerevisiae. Stationary assays were performed with yeast biomass harvested from the stationary phase of an anaerobic fermentation process, with separate additions of 0.1, 1.0 and 10.0 mg/L of both fungicides. Removal studies with stationary phase cells were performed with viable and non-viable cells inactivated with sodium azide. This study clearly shows that both Saccharomyces cerevisiae strains were able to remove fenhexamid and pyrimethanil in stationary and fermentative assays. The removal potential is shown to be strain dependent in stationary but not in fermentative assays. However, the removal potential is dependent on the type of fungicide in both stationary and fermentative assays. In stationary phase cultures no significant difference in fungicide removal potential between viable and non-viable cells was observed, indicating that both pesticides were not degraded by metabolically active cells. However, the presence of both pesticides influenced fermentation kinetics and only pyrimethanil at 10.0 mg/L increased the production of volatile acidity of both strains.

Bakery by-products based feeds borne-Saccharomyces cerevisiae strains with probiotic and antimycotoxin effects plus antibiotic resistance properties for use in animal production.

Science.gov (United States)

Poloni, Valeria; Salvato, Lauranne; Pereyra, Carina; Oliveira, Aguida; Rosa, Carlos; Cavaglieri, Lilia; Keller, Kelly Moura

2017-09-01

The aim of this study was to select S. cerevisiae strains able to exert probiotic and antimycotoxin effects plus antibiotics resistance properties for use in animal production. S. cerevisiae LL74 and S. cerevisiae LL83 were isolated from bakery by-products intended for use in animal feed and examined for phenotypic characteristics and nutritional profile. Resistance to antibiotic, tolerance to gastrointestinal conditions, autoaggregation and coaggregation assay, antagonism to animal pathogens and aflatoxin B 1 binding were studied. S. cerevisiae LL74 and S. cerevisiae LL83 showed resistance to all the antibiotics assayed (ampicillin, streptomycin, neomycin, norfloxacin, penicillin G, sulfonamide and trimethoprim). The analysis showed that exposure time to acid pH had a significant impact onto the viable cell counts onto both yeast strains. Presence of bile 0.5% increased significantly the growth of the both yeast strains. Moreover, they were able to tolerate the simulated gastrointestinal conditions assayed. In general, the coaggregation was positive whereas the autoaggregation capacity was not observed. Both strains were able to adsorb AFB 1 . In conclusion, selected S. cerevisiae LL74 and S. cerevisiae LL83 have potential application to be used as a biological method in animal feed as antibiotic therapy replacement in, reducing the adverse effects of AFB 1 and giving probiotic properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dynamics of Storage Carbohydrates Metabolism in Saccharomyces cerevisiae

OpenAIRE

Suarez-Mendez, C.A.

2015-01-01

Production of chemicals via biotechnological routes are becoming rapidly an alternative to oil-based processes. Several microorganisms including yeast, bacteria, fungi and algae can transform feedstocks into high-value molecules at industrial scale. Improvement of the bioprocess performance is a key factor for making this technology economically feasible. Despite the vast knowledge on microbial metabolism, some gaps still remain open. In Saccharomyces cerevisiae, metabolism of storage carbohy...

Genome-wide transcription survey on flavour production in Saccharomyces cerevisiae

NARCIS (Netherlands)

Schoondermark-Stolk, Sung A.; Jansen, Michael; Verkleij, Arie J.; Verrips, C. Theo; Euverink, Gert-Jan W.; Dijkhuizen, Lubbert; Boonstra, Johannes

2006-01-01

The yeast Saccharomyces cerevisiae is widely used as aroma producer in the preparation of fermented foods and beverages. During food fermentations, secondary metabolites like 3-methyl-1-butanol, 4-methyl-2-oxopentanoate, 3-methyl-2-oxobutanoate and 3-methylbutyrate emerge. These four compounds have

Reconstitution of an efficient thymidine salvage pathway in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Vernis, L.; Piskur, Jure; Diffley, J.F.X.

2003-01-01

The budding yeast Saccharomyces cerevisiae is unable to incorporate exogenous nucleosides into DNA. We have made a number of improvements to existing strategies to reconstitute an efficient thymidine salvage pathway in yeast. We have constructed strains that express both a nucleoside kinase as well...

Study On Ethanol Production From Sugar Cane Molasses By Using Irradiated Saccharomyces Cerevisiae

International Nuclear Information System (INIS)

Botros, H.W.; Armed, A.S.; Farag, S.S.; Hassan, L.A.

2012-01-01

In commercial ethanol production procedures often use sugar cane molasses as a raw material due to- their abundance and low costs. The most employed microorganisms used for fermentation is Saccharomyces cerevisiae yeasts due to their ability to hydrolyze sucrose from sugar cane molasses into glucose and fructose; two easily assimilable hexoses. The aim of this study was to evaluate the effect of gamma irradiation on the activity of S. cerevisiae in the ethanol production yeast cells exposed to different doses of gamma rays (0.05, 0.1, 0.2, 0.4, 0.6, 0.8 and 1.0 KGy. The sugar cane substrate was optimized after maintaining deferent levels of sugar concentrations (12-21%), medium ph (4.0-5.5), incubation temperature (25-40 degree C) and rate of fermentation (24-168 h). The data showed that the rate of ethanol production reached its maximum by using the irradiated S. cerevisiae cells at 0.1 kGy dose at fermentation conditions as 15% sugar concentration, ph 4.5, incubation temperature 30 degree C, fermentation time 96 h at a fermentation medium volume 250 ml found in 500 ml Erlenmeyer flasks.

The expression of glycerol facilitators from various yeast species improves growth on glycerol of Saccharomyces cerevisiae

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Mathias Klein

2016-12-01

Full Text Available Glycerol is an abundant by-product during biodiesel production and additionally has several assets compared to sugars when used as a carbon source for growing microorganisms in the context of biotechnological applications. However, most strains of the platform production organism Saccharomyces cerevisiae grow poorly in synthetic glycerol medium. It has been hypothesized that the uptake of glycerol could be a major bottleneck for the utilization of glycerol in S. cerevisiae. This species exclusively relies on an active transport system for glycerol uptake. This work demonstrates that the expression of predicted glycerol facilitators (Fps1 homologues from superior glycerol-utilizing yeast species such as Pachysolen tannophilus, Komagataella pastoris, Yarrowia lipolytica and Cyberlindnera jadinii significantly improves the growth performance on glycerol of the previously selected glycerol-consuming S. cerevisiae wild-type strain (CBS 6412-13A. The maximum specific growth rate increased from 0.13 up to 0.18 h−1 and a biomass yield coefficient of 0.56 gDW/gglycerol was observed. These results pave the way for exploiting the assets of glycerol in the production of fuels, chemicals and pharmaceuticals based on baker's yeast. Keywords: Yeast, Saccharomyces cerevisiae, Glycerol, Transport, Glycerol facilitator, Fps1, Stl1

On cycles in the transcription network of Saccharomyces cerevisiae

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Berman Piotr

2008-01-01

Full Text Available Abstract Background We investigate the cycles in the transcription network of Saccharomyces cerevisiae. Unlike a similar network of Escherichia coli, it contains many cycles. We characterize properties of these cycles and their place in the regulatory mechanism of the cell. Results Almost all cycles in the transcription network of Saccharomyces cerevisiae are contained in a single strongly connected component, which we call LSCC (L for "largest", except for a single cycle of two transcription factors. The fact that LSCC includes almost all cycles is well explained by the properties of a random graph with the same in- and out-degrees of the nodes. Among different physiological conditions, cell cycle has the most significant relationship with LSCC, as the set of 64 transcription interactions that are active in all phases of the cell cycle has overlap of 27 with the interactions of LSCC (of which there are 49. Conversely, if we remove the interactions that are active in all phases of the cell cycle (25% of interactions to transcription factors, the LSCC would have only three nodes and 5 edges, many fewer than expected. This subgraph of the transcription network consists mostly of interactions that are active only in the stress response subnetwork. We also characterize the role of LSCC in the topology of the network. We show that LSCC can be used to define a natural hierarchy in the network and that in every physiological subnetwork LSCC plays a pivotal role. Conclusion Apart from those well-defined conditions, the transcription network of Saccharomyces cerevisiae is devoid of cycles. It was observed that two conditions that were studied and that have no cycles of their own are exogenous: diauxic shift and DNA repair, while cell cycle and sporulation are endogenous. We claim that in a certain sense (slow recovery stress response is endogenous as well.

Enhanced isoprenoid production from xylose by engineered Saccharomyces cerevisiae.

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Kwak, Suryang; Kim, Soo Rin; Xu, Haiqing; Zhang, Guo-Chang; Lane, Stephan; Kim, Heejin; Jin, Yong-Su

2017-11-01

Saccharomyces cerevisiae has limited capabilities for producing fuels and chemicals derived from acetyl-CoA, such as isoprenoids, due to a rigid flux partition toward ethanol during glucose metabolism. Despite numerous efforts, xylose fermentation by engineered yeast harboring heterologous xylose metabolic pathways was not as efficient as glucose fermentation for producing ethanol. Therefore, we hypothesized that xylose metabolism by engineered yeast might be a better fit for producing non-ethanol metabolites. We indeed found that engineered S. cerevisiae on xylose showed higher expression levels of the enzymes involved in ethanol assimilation and cytosolic acetyl-CoA synthesis than on glucose. When genetic perturbations necessary for overproducing squalene and amorphadiene were introduced into engineered S. cerevisiae capable of fermenting xylose, we observed higher titers and yields of isoprenoids under xylose than glucose conditions. Specifically, co-overexpression of a truncated HMG1 (tHMG1) and ERG10 led to substantially higher squalene accumulation under xylose than glucose conditions. In contrast to glucose utilization producing massive amounts of ethanol regardless of aeration, xylose utilization allowed much less amounts of ethanol accumulation, indicating ethanol is simultaneously re-assimilated with xylose consumption and utilized for the biosynthesis of cytosolic acetyl-CoA. In addition, xylose utilization by engineered yeast with overexpression of tHMG1, ERG10, and ADS coding for amorphadiene synthase, and the down-regulation of ERG9 resulted in enhanced amorphadiene production as compared to glucose utilization. These results suggest that the problem of the rigid flux partition toward ethanol production in yeast during the production of isoprenoids and other acetyl-CoA derived chemicals can be bypassed by using xylose instead of glucose as a carbon source. Biotechnol. Bioeng. 2017;114: 2581-2591. © 2017 Wiley Periodicals, Inc. © 2017 Wiley

Els escriptors finiseculars a la llar hispana i els fluents llindars d'un model d'interliterarietat

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Juan M. Ribera Llopis

2014-03-01

espectre fins a un cas concret —el de Caterina Albert i Paradís, Víctor Català, i el seu «vedat»—, exercici que pot ajudar a indagar sobre algun dels seus dobles vessants. En particular, s’interroga sobre l’abast de la combinatòria possible entre identitat i correspondències intel·lectuals i artístiques.

Increase of fruity aroma during mixed T. delbrueckii/S. cerevisiae wine fermentation is linked to specific esters enhancement.

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Renault, Philippe; Coulon, Joana; de Revel, Gilles; Barbe, Jean-Christophe; Bely, Marina

2015-08-17

The aim of this work was to study ester formation and the aromatic impact of Torulaspora delbrueckii when used in association with Saccharomyces cerevisiae during the alcoholic fermentation of must. In order to evaluate the influence of the inoculation procedure, sequential and simultaneous mixed cultures were carried out and compared to pure cultures of T. delbrueckii and S. cerevisiae. Our results showed that mixed inoculations allowed the increase, in comparison to S. cerevisiae pure culture, of some esters specifically produced by T. delbrueckii and significantly correlated to the maximal T. delbrueckii population reached in mixed cultures. Thus, ethyl propanoate, ethyl isobutanoate and ethyl dihydrocinnamate were considered as activity markers of T. delbrueckii. On the other hand, isobutyl acetate and isoamyl acetate concentrations were systematically increased during mixed inoculations although not correlated with the development of either species but were rather due to positive interactions between these species. Favoring T. delbrueckii development when performing sequential inoculation enhanced the concentration of esters linked to T. delbrueckii activity. On the contrary, simultaneous inoculation restricted the growth of T. delbrueckii, limiting the production of its activity markers, but involved a very important production of numerous esters due to more important positive interactions between species. These results suggest that the ester concentrations enhancement via interactions during mixed modalities was due to S. cerevisiae production in response to the presence of T. delbrueckii. Finally, sensory analyses showed that mixed inoculations between T. delbrueckii and S. cerevisiae allowed to enhance the complexity and fruity notes of wine in comparison to S. cerevisiae pure culture. Furthermore, the higher levels of ethyl propanoate, ethyl isobutanoate, ethyl dihydrocinnamate and isobutyl acetate in mixed wines were found responsible for the increase of

Chromosome VIII disomy influences the nonsense suppression efficiency and transition metal tolerance of the yeast Saccharomyces cerevisiae.

Science.gov (United States)

Zadorsky, S P; Sopova, Y V; Andreichuk, D Y; Startsev, V A; Medvedeva, V P; Inge-Vechtomov, S G

2015-06-01

The SUP35 gene of the yeast Saccharomyces cerevisiae encodes the translation termination factor eRF3. Mutations in this gene lead to the suppression of nonsense mutations and a number of other pleiotropic phenotypes, one of which is impaired chromosome segregation during cell division. Similar effects result from replacing the S. cerevisiae SUP35 gene with its orthologues. A number of genetic and epigenetic changes that occur in the sup35 background result in partial compensation for this suppressor effect. In this study we showed that in S. cerevisiae strains in which the SUP35 orthologue from the yeast Pichia methanolica replaces the S. cerevisiae SUP35 gene, chromosome VIII disomy results in decreased efficiency of nonsense suppression. This antisuppressor effect is not associated with decreased stop codon read-through. We identified SBP1, a gene that localizes to chromosome VIII, as a dosage-dependent antisuppressor that strongly contributes to the overall antisuppressor effect of chromosome VIII disomy. Disomy of chromosome VIII also leads to a change in the yeast strains' tolerance of a number of transition metal salts. Copyright © 2015 John Wiley & Sons, Ltd.

The evolution of gene expression QTL in Saccharomyces cerevisiae.

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James Ronald

2007-08-01

Full Text Available Understanding the evolutionary forces that influence patterns of gene expression variation will provide insights into the mechanisms of evolutionary change and the molecular basis of phenotypic diversity. To date, studies of gene expression evolution have primarily been made by analyzing how gene expression levels vary within and between species. However, the fundamental unit of heritable variation in transcript abundance is the underlying regulatory allele, and as a result it is necessary to understand gene expression evolution at the level of DNA sequence variation. Here we describe the evolutionary forces shaping patterns of genetic variation for 1206 cis-regulatory QTL identified in a cross between two divergent strains of Saccharomyces cerevisiae. We demonstrate that purifying selection against mildly deleterious alleles is the dominant force governing cis-regulatory evolution in S. cerevisiae and estimate the strength of selection. We also find that essential genes and genes with larger codon bias are subject to slightly stronger cis-regulatory constraint and that positive selection has played a role in the evolution of major trans-acting QTL.

Production of 3-hydroxypropionic acid from glucose and xylose by metabolically engineered Saccharomyces cerevisiae

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Kanchana R. Kildegaard

2015-12-01

Full Text Available Biomass, the most abundant carbon source on the planet, may in the future become the primary feedstock for production of fuels and chemicals, replacing fossil feedstocks. This will, however, require development of cell factories that can convert both C6 and C5 sugars present in lignocellulosic biomass into the products of interest. We engineered Saccharomyces cerevisiae for production of 3-hydroxypropionic acid (3HP, a potential building block for acrylates, from glucose and xylose. We introduced the 3HP biosynthetic pathways via malonyl-CoA or β-alanine intermediates into a xylose-consuming yeast. Using controlled fed-batch cultivation, we obtained 7.37±0.17 g 3HP L−1 in 120 hours with an overall yield of 29±1% Cmol 3HP Cmol−1 xylose. This study is the first demonstration of the potential of using S. cerevisiae for production of 3HP from the biomass sugar xylose. Keywords: Metabolic engineering, Biorefineries, 3-hydroxypropionic acid, Saccharomyces cerevisiae, Xylose utilization

Increased ethanol production by deletion of HAP4 in recombinant xylose-assimilating Saccharomyces cerevisiae.

Science.gov (United States)

Matsushika, Akinori; Hoshino, Tamotsu

2015-12-01

The Saccharomyces cerevisiae HAP4 gene encodes a transcription activator that plays a key role in controlling the expression of genes involved in mitochondrial respiration and reductive pathways. This work examines the effect of knockout of the HAP4 gene on aerobic ethanol production in a xylose-utilizing S. cerevisiae strain. A hap4-deleted recombinant yeast strain (B42-DHAP4) showed increased maximum concentration, production rate, and yield of ethanol compared with the reference strain MA-B42, irrespective of cultivation medium (glucose, xylose, or glucose/xylose mixtures). Notably, B42-DHAP4 was capable of producing ethanol from xylose as the sole carbon source under aerobic conditions, whereas no ethanol was produced by MA-B42. Moreover, the rate of ethanol production and ethanol yield (0.44 g/g) from the detoxified hydrolysate of wood chips was markedly improved in B42-DHAP4 compared to MA-B42. Thus, the results of this study support the view that deleting HAP4 in xylose-utilizing S. cerevisiae strains represents a useful strategy in ethanol production processes.

Crystallization and preliminary X-ray diffraction analysis of motif N from Saccharomyces cerevisiae Dbf4

International Nuclear Information System (INIS)

Matthews, Lindsay A.; Duong, Andrew; Prasad, Ajai A.; Duncker, Bernard P.; Guarné, Alba

2009-01-01

To understand the role of the Cdc7–Dbf4 complex in checkpoint responses, a fragment of Saccharomyces cerevisiae Dbf4 encompassing motif N was isolated, overproduced and crystallized. The Cdc7–Dbf4 complex plays an instrumental role in the initiation of DNA replication and is a target of replication-checkpoint responses in Saccharomyces cerevisiae. Cdc7 is a conserved serine/threonine kinase whose activity depends on association with its regulatory subunit, Dbf4. A conserved sequence near the N-terminus of Dbf4 (motif N) is necessary for the interaction of Cdc7–Dbf4 with the checkpoint kinase Rad53. To understand the role of the Cdc7–Dbf4 complex in checkpoint responses, a fragment of Saccharomyces cerevisiae Dbf4 encompassing motif N was isolated, overproduced and crystallized. A complete native data set was collected at 100 K from crystals that diffracted X-rays to 2.75 Å resolution and structure determination is currently under way

Air-liquid biofilm formation is dependent on ammonium depletion in a Saccharomyces cerevisiae flor strain.

Science.gov (United States)

Zara, Giacomo; Budroni, Marilena; Mannazzu, Ilaria; Zara, Severino

2011-12-01

Air-liquid biofilm formation appears to be an adaptive mechanism that promotes foraging of Saccharomyces cerevisiae flor strains in response to nutrient starvation. The FLO11 gene plays a central role in this phenotype as its expression allows yeast cells to rise to the liquid surface. Here, we investigated the role of ammonium depletion in air-liquid biofilm formation and FLO11 expression in a S. cerevisiae flor strain. The data obtained show that increasing ammonium concentrations from 0 to 450 m m reduce air-liquid biofilm in terms of biomass and velum formation and correlate with a reduction of FLO11 expression. Rapamycin inhibition of the TOR pathway and deletion of RAS2 gene significantly reduced biofilm formation and FLO11 expression. Taken together, these data suggest that ammonium depletion is a key factor in the induction of air-liquid biofilm formation and FLO11 expression in S. cerevisiae flor strains. Copyright © 2011 John Wiley & Sons, Ltd.

Starmerella bombicola influences the metabolism of Saccharomyces cerevisiae at pyruvate decarboxylase and alcohol dehydrogenase level during mixed wine fermentation

Science.gov (United States)

2012-01-01

Background The use of a multistarter fermentation process with Saccharomyces cerevisiae and non-Saccharomyces wine yeasts has been proposed to simulate natural must fermentation and to confer greater complexity and specificity to wine. In this context, the combined use of S. cerevisiae and immobilized Starmerella bombicola cells (formerly Candida stellata) was assayed to enhance glycerol concentration, reduce ethanol content and to improve the analytical composition of wine. In order to investigate yeast metabolic interaction during controlled mixed fermentation and to evaluate the influence of S. bombicola on S. cerevisiae, the gene expression and enzymatic activity of two key enzymes of the alcoholic fermentation pathway such as pyruvate decarboxylase (Pdc1) and alcohol dehydrogenase (Adh1) were studied. Results The presence of S. bombicola immobilized cells in a mixed fermentation trial confirmed an increase in fermentation rate, a combined consumption of glucose and fructose, an increase in glycerol and a reduction in the production of ethanol as well as a modification in the fermentation of by products. The alcoholic fermentation of S. cerevisiae was also influenced by S. bombicola immobilized cells. Indeed, Pdc1 activity in mixed fermentation was lower than that exhibited in pure culture while Adh1 activity showed an opposite behavior. The expression of both PDC1 and ADH1 genes was highly induced at the initial phase of fermentation. The expression level of PDC1 at the end of fermentation was much higher in pure culture while ADH1 level was similar in both pure and mixed fermentations. Conclusion In mixed fermentation, S. bombicola immobilized cells greatly affected the fermentation behavior of S. cerevisiae and the analytical composition of wine. The influence of S. bombicola on S. cerevisiae was not limited to a simple additive contribution. Indeed, its presence caused metabolic modifications during S. cerevisiae fermentation causing variation in the gene

Starmerella bombicola influences the metabolism of Saccharomyces cerevisiae at pyruvate decarboxylase and alcohol dehydrogenase level during mixed wine fermentation

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Milanovic Vesna

2012-02-01

Full Text Available Abstract Background The use of a multistarter fermentation process with Saccharomyces cerevisiae and non-Saccharomyces wine yeasts has been proposed to simulate natural must fermentation and to confer greater complexity and specificity to wine. In this context, the combined use of S. cerevisiae and immobilized Starmerella bombicola cells (formerly Candida stellata was assayed to enhance glycerol concentration, reduce ethanol content and to improve the analytical composition of wine. In order to investigate yeast metabolic interaction during controlled mixed fermentation and to evaluate the influence of S. bombicola on S. cerevisiae, the gene expression and enzymatic activity of two key enzymes of the alcoholic fermentation pathway such as pyruvate decarboxylase (Pdc1 and alcohol dehydrogenase (Adh1 were studied. Results The presence of S. bombicola immobilized cells in a mixed fermentation trial confirmed an increase in fermentation rate, a combined consumption of glucose and fructose, an increase in glycerol and a reduction in the production of ethanol as well as a modification in the fermentation of by products. The alcoholic fermentation of S. cerevisiae was also influenced by S. bombicola immobilized cells. Indeed, Pdc1 activity in mixed fermentation was lower than that exhibited in pure culture while Adh1 activity showed an opposite behavior. The expression of both PDC1 and ADH1 genes was highly induced at the initial phase of fermentation. The expression level of PDC1 at the end of fermentation was much higher in pure culture while ADH1 level was similar in both pure and mixed fermentations. Conclusion In mixed fermentation, S. bombicola immobilized cells greatly affected the fermentation behavior of S. cerevisiae and the analytical composition of wine. The influence of S. bombicola on S. cerevisiae was not limited to a simple additive contribution. Indeed, its presence caused metabolic modifications during S. cerevisiae fermentation

Integrated phospholipidomics and transcriptomics analysis of Saccharomyces cerevisiae with enhanced tolerance to a mixture of acetic acid, furfural, and phenol

Science.gov (United States)

A mixture of acetic acid, furfural and phenol (AFP), three representative lignocellulose derived inhibitors, significantly inhibited the growth and bioethanol production of Saccharomyces cerevisiae. In order to uncover mechanisms behind the enhanced tolerance of an inhibitor-tolerant S.cerevisiae s...

Quality and Composition of Airén Wines Fermented by Sequential Inoculation of Lachancea thermotolerans and Saccharomyces cerevisiae

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Ángel Benito

2016-01-01

Full Text Available This study evaluates the influence of Lachancea thermotolerans on low-acidity Airén grape must from the south of Spain. For this purpose, combined fermentations with Lachancea thermotolerans and Saccharomyces cerevisiae were compared to a single fermentation by S. cerevisiae. Results of all developed analyses showed significant differences in several parameters including acidity, population growth kinetics, concentration of amino acids, volatile and non-volatile compounds, and sensorial parameters. The Airén wine quality increased mainly due to the acidification by L. thermotolerans. The acidification process caused a lactic acid increment of 3.18 g/L and a reduction of 0.22 in pH compared to the control fermentation, performed by S. cerevisiae.

Música Popular Brasileira no contexto das tecnologias digitais: a produção independente e a emergência de novas estratégias e representações sobre as identidades musicais

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Thiago Pires Galletta

2011-07-01

Full Text Available

O presente artigo tem como objetivo refletir sobre as novas condições de formação e estabelecimento das identidades musicais no campo da música popular brasileira, emergentes a partir do avanço das tecnologias digitais de produção e distribuição musical, durante a última década. Considerando a contínua expansão e sedimentação da produção independente, verificada neste contexto, busca-se discutir e problematizar alguns dos marcos tradicionais de análise que tem referenciado parte importante dos estudos deste campo até aqui, como é o caso da relação entre grande Indústria Fonográfica e produção musical.   

Transformações recentes na gestão de desenvolvimento urbano: alguns exemplos internacionais

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Claudete de Castro SILVA

1998-12-01

Full Text Available Este trabalho objetiva apresentar o "estado da arte" da literatura sobre as recentes transformações na gestão urbana ocorridas nos países onde a globalização e os processos de descentralização têm sido notáveis. Cada estudo de caso mostra uma faceta que permite compor uma interpretação sobre as transformações da gestão urbana. São analisados os casos da França, dos EUA, Japão e Alemanha, cujas transformações são referências para pensar futuros estudos de casos brasileiros

Bioaccumulation of uranium from waste water using different strains of Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Tykva, R.; Novak, J.; Podracka, E.; Popa, K.

2009-01-01

Five different strains of Saccharomyces cerevisiae were tested for their abilities to accumulate uranium from waste water containing competitive ions. Samples of water passing out from a previous uranium mill were used. The strains tested possess different abilities to accumulate uranium. The kinetics of bioaccumulation, the leaching degree, the influence of cell density and their origin were investigated. Under the applied experimental conditions, more than a half of the total activity (uranium and the decay products) could be accumulated after 60 min contact time of 1 mL (S. cerevisiae) suspension and 5 mL of water. The other cations present in solution effectively competed for the uranium accumulation. 226 Ra and its decay products were completely retained using all tested strains. (authors)

Toxicological effects of multi-walled carbon nanotubes on Saccharomyces cerevisiae: The uptake kinetics and mechanisms and the toxic responses

Energy Technology Data Exchange (ETDEWEB)

Zhu, Song; Zhu, Bin; Huang, Aiguo [College of Animal Science and Technology, Northwest A& F University, Yangling 712100 (China); Hu, Yang [College of Science, Northwest A& F University, Yangling 712100 (China); Wang, Gaoxue, E-mail: wanggaoxue@126.com [College of Animal Science and Technology, Northwest A& F University, Yangling 712100 (China); Ling, Fei, E-mail: feiling@nwsuaf.edu.cn [College of Animal Science and Technology, Northwest A& F University, Yangling 712100 (China)

2016-11-15

Highlights: • MWCNTs (<100 mg/L) were not toxic to S. cerevisiae. • MWCNTs were internalized in S. cerevisiae cells by three pathways. • The uptake kinetics and the subcellular distribution of MWCNTs in S. cerevisiae cells were shown. • S. cerevisiae cells were undergoing apoptosis by mitochondrial impairment pathway. - Abstract: Using Saccharomyces cerevisiae as an experimental model, the potential toxicological effects of oxidized multi-walled carbon nanotubes (MWCNTs) were investigated following exposure to 0–600 mg/L for 24 h. Results indicated that MWCNTs (>100 mg/L) had adverse effects on the cell proliferation. MWCNTs were clearly visible in lysosome, vacuole, endosome, mitochondria, multivesicular body and localization in the perinuclear region. The uptake kinetics data demonstrated that the maximum MWCNTs content (209.61 mg/g) was reached at 3 h, and a steady state was reached after 18 h. Based on the combined results of transmission electron microscope, endocytosis inhibition experiments and endocytosis-related genes (END3, END6, Sla2 and Rsp5) expression analysis, we elucidated MWCNTs uptake mechanism: (i) via a direct penetration of single MWCNTs; (ii) via endocytosis of single MWCNTs; and (iii) via endocytosis of MWCNTs aggregates. The percentage of apoptosis was significant increased at 600 mg/L. The decrease of mitochondrial transmembrane potential and the leakage of cytochrome c shown dose-dependent manners. Interestingly, there was no significant increase of reactive oxygen species (ROS). The apoptosis-related genes (SOD1, SOD2, Yca1, Nma111 and Nuc1) were significant changed. These results obtained in our study demonstrated that oxidized MWCNTs induce Saccharomyces cerevisiae apoptosis via mitochondrial impairment pathway.

Properties of promoters cloned randomly from the Saccharomyces cerevisiae genome.

Science.gov (United States)

Santangelo, G M; Tornow, J; McLaughlin, C S; Moldave, K

1988-01-01

Promoters were isolated at random from the genome of Saccharomyces cerevisiae by using a plasmid that contains a divergently arrayed pair of promoterless reporter genes. A comprehensive library was constructed by inserting random (DNase I-generated) fragments into the intergenic region upstream from the reporter genes. Simple in vivo assays for either reporter gene product (alcohol dehydrogenase or beta-galactosidase) allowed the rapid identification of promoters from among these random fragments. Poly(dA-dT) homopolymer tracts were present in three of five randomly cloned promoters. With two exceptions, each RNA start site detected was 40 to 100 base pairs downstream from a TATA element. All of the randomly cloned promoters were capable of activating reporter gene transcription bidirectionally. Interestingly, one of the promoter fragments originated in a region of the S. cerevisiae rDNA spacer; regulated divergent transcription (presumably by RNA polymerase II) initiated in the same region. Images PMID:2847031

Silver Uptake and Reuse of Biomass by Saccharomyces cerevisiae ...

African Journals Online (AJOL)

Studies were carried out on the recovery of bound silver and reuse of Chlorella emersonii and Saccharomyces cerevisiae biomass for further silver uptake after they were placed in contact with 20mg/l silver for 30 minutes to allow for maximum binding. It was found that 0.16M nitric acid gave the best recovery rates of silver.

Hydrogen peroxide removal with magnetically responsive Saccharomyces cerevisiae cells

Czech Academy of Sciences Publication Activity Database

Šafařík, Ivo; Maděrová, Zdeňka; Šafaříková, Miroslava

2008-01-01

Roč. 56, - (2008), s. 7925-7928 ISSN 0021-8561 R&D Projects: GA MPO 2A-1TP1/094; GA MŠk OC 157 Institutional research plan: CEZ:AV0Z60870520 Keywords : magnetic alginate beads * catalase * magnetic separation * Saccharomyces cerevisiae cells * hydrogen peroxide Subject RIV: GM - Food Processing Impact factor: 2.562, year: 2008

Kinetics of formation of induced mutants of Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Chepurnoj, A.I.; Levkovich, N.V.; Mikhova-Tsenova, N.; Mel'nikova, L.A.

1990-01-01

UV and γ-radiation mutagenic effect an various strains of Saccharomyces cerevisiae was studied by analyzing formation kinetics of induced mutants at the period of postirradiation incubation. Mechanisms of induced reverse formation was suggested. The presented analysis is considered to be differential taking account of more subtle aspects of induced mutagenesis. 8 refs.; 10 figs.; 3 tabs

Glucose repression in Saccharomyces cerevisiae.

Science.gov (United States)

Kayikci, Ömur; Nielsen, Jens

2015-09-01

Glucose is the primary source of energy for the budding yeast Saccharomyces cerevisiae. Although yeast cells can utilize a wide range of carbon sources, presence of glucose suppresses molecular activities involved in the use of alternate carbon sources as well as it represses respiration and gluconeogenesis. This dominant effect of glucose on yeast carbon metabolism is coordinated by several signaling and metabolic interactions that mainly regulate transcriptional activity but are also effective at post-transcriptional and post-translational levels. This review describes effects of glucose repression on yeast carbon metabolism with a focus on roles of the Snf3/Rgt2 glucose-sensing pathway and Snf1 signal transduction in establishment and relief of glucose repression. © FEMS 2015.

Efetividade de uma técnica educativa na aquisição de conhecimentos por pais sobre uso racional do flúor = Effectiveness of an educative techinique on knowledge acquisition on ratinal use of fluorine by parents

Directory of Open Access Journals (Sweden)

Martins, Carolina de Castro

2006-01-01

Full Text Available O objetivo do presente estudo foi testar o conhecimento sobre uso racional de flúor adquirido através de grupo de discussão (GD. Um grupo de 47 pais de crianças pré-escolares constituiu a amostra após a assinatura de um termo de consentimento livre e esclarecido. Este estudo foi aprovado por um Comitê de ética em Pesquisa. Para averiguação do nível de conhecimento inicial sobre o tema proposto, os participantes responderam a um questionário com 14 perguntas abertas e fechadas. Seis meses após esta etapa, foi realizado um GD sobre o uso racional de flúor. O GD proposto abordou a metodologia pedagógica problematizadora e contou com a participação ativa dos pais e de três cirurgiões dentistas. Neste momento foram apresentadas afirmações sobre a utilização do flúor pela população, a partir das quais a discussão era deflagrada. Alguns dias após, os pais responderam novamente o questionário inicial. Os dados foram submetidos aos testes estatístico Qui-quadrado e exato de Fisher através do programa SPSS. Houve diferença estatisticamente significante entre praticamente todas as respostas no primeiro e segundo questionários (p < 0,005, sendo que no segundo, houve um maior número de respostas corretas. A técnica educativa avaliada mostrou-se efetiva na incorporação de novos conhecimentos sobre o uso racional de flúor pelos pais, evidenciando a eficácia da metodologia empregada

Toxicidade residual de alguns agrotóxicos recomendado na agricultura sobre Neoseiulus californicus (McGregor (Acari: Phytoseiidae Residual toxicity of some pesticides recommended for citrus orchards on the predaceous mite Neoseiulus californicus (McGregor (Acari: phytoseiidae

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Marcos Zatti da Silva

2007-04-01

Full Text Available O objetivo do trabalho foi avaliar a toxicidade residual de alguns agrotóxicos utilizados em citros sobre Neoseiulus californicus (McGregor em condições de laboratório. O método de bioensaio adotado foi o de contato residual. Folhas de citros da variedade Pêra, acondicionadas em arenas, foram pulverizadas em torre de Potter. A toxicidade residual dos produtos foi avaliada duas horas e 1; 3; 5; 7; 10; 14 e 21 dias após a aplicação. Em cada arena, foram transferidas dez fêmeas adultas de N. californicus, juntamente com uma quantidade suficiente de Tetranychus urticae, como fonte de alimento. As avaliações de mortalidade foram realizadas 72 horas após a transferência dos ácaros para as arenas. Os agrotóxicos acrinathrin, deltamethrin, dinocap, enxofre, fenpropathrin, óxido de fenbutatin e propargite não causaram mortalidades significativas em adultos de N. californicus. Foram registradas mortalidades de 29,8; 24,0 e 34,1% para ácaros N. californicus expostos a resíduos de duas horas de idade de abamectim, azocyclotin e cyhexatin, respectivamente. Dicofol, pyridaben e chlorfenapyr causaram 100% de mortalidade aos ácaros predadores expostos aos resíduos tóxicos dos acaricidas, com duas horas de idade. Abamectin provocou mortalidade significativa por um período inferior a um dia. Resíduos dos acaricidas azocyclotin, cyhexatin, dicofol, pyridaben e chlorfenapyr provocaram mortalidades significativas por períodos de 1; 1; 10; 10 e 21dias, respectivamente. Os resultados obtidos no presente experimento servem de subsídio para a escolha adequada dos agrotóxicos a serem utilizados em pomares de citros nos quais N. californicus esteja presente ou naqueles em que o predador venha a ser liberado. Esses resultados também servem para a escolha do momento mais favorável para a liberação dos ácaros predadores dessa espécie no campo, após a aplicação de agrotóxicos nos pomares. Estudos conduzidos em condições de campo ainda s

RESISTÊNCIA À FLEXÃO ESTÁTICA DE ALGUNS PAINÉIS AGLOMERADOS COMERCIALIZADOS NO RIO GRANDE DO SUL

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Clovis Roberto Haselein

2000-12-01

Full Text Available Foram testados em flexão estática sete tipos de painéis aglomerados comercializados no RS. De cada tipo, foram retirados ao acaso cinco painéis e de cada um destes cortados três corpos de prova para os ensaios de flexão segundo a norma ASTM D1037-93 (1995. Os resultados indicam que os painéis enquadram-se nos critérios das normas norte-americanas de padronização. Para alguns tipos de painéis foi possível estabelecer modelos matemáticos relacionando módulos de elasticidade e de ruptura à massa específica.

Ontem, hoje e amanhã: sobre a web e as ferramentas colaborativas emergentes para o professor de língua estrangeira

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Alan Ricardo Costa

2016-12-01

Full Text Available Considerando que “[...] só é possível prever o futuro quando se olha para o passado” (LEFFA, 2012, p.404, se faz necessário investigar o passado e o presente da web, das Tecnologias de Informação e Comunicação (TIC e das tecnologias educacionais para o ensino e a aprendizagem de Línguas Estrangeira (LE, para especular sobre o futuro, por mais incerto que este seja. Assim, o objetivo deste trabalho é apresentar e discutir as mudanças nas TIC e ferramentas educacionais, do passado para o presente, para apontar perspectivas emergentes ao alcance do professor de LE. Os resultados - que partem de observações sobre alguns recursos e ferramentas digitais disponíveis no Repositório Acción E/LE (Espanhol como Língua Estrangeira - indicam que: (1 recursos online e TIC em geral não tendem a negar o antigo, mas sim incorporá-lo ao novo, fazendo com que tais recursos estejam em contínua evolução; (2 esta evolução, consequentemente, acontece de forma gradual e complexa: nem todas as TIC e tecnologias educacionais mudam ao mesmo tempo ou na mesma medida; (3 a tendência mais visível e emergente é, possivelmente, a colaboração em massa subjacente às ferramentas e seus usos, o que explica o surgimento dos Recursos Educacionais Abertos (REA, por exemplo.

De perto e de dentro: notas para uma etnografia urbana

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Magnani José Guilherme Cantor

2002-01-01

Full Text Available O texto busca pôr em relação duas linhas de análise, uma sobre cidade e outra sobre etnografia. O objetivo é discutir as possibilidades que este enfoque, próprio da antropologia, abre para o estudo da dinâmica urbana. Tomando como ponto de partida a apresentação de alguns quadros analíticos sobre o fenômeno urbano contemporâneo, caracterizados como um "olhar de fora e de longe", é desenvolvida a perspectiva da etnografia, chamada, por contraste, de um "olhar de perto e de dentro". Explicitados os pressupostos teóricos que sustentam essa posição, é apresentada uma estratégia de pesquisa com base nessa argumentação para, finalmente, mostrar seu uso em alguns exemplos etnográficos mais recentes. O argumento termina sinalizando que um olhar "distanciado" amplia e complementa a perspectiva proposta, possibilitando a articulação do recorte etnográfico, bem delimitado, com planos e modelos mais gerais de análise.

Bulk segregant analysis by high-throughput sequencing reveals a novel xylose utilization gene from Saccharomyces cerevisiae.

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Jared W Wenger

2010-05-01

Full Text Available Fermentation of xylose is a fundamental requirement for the efficient production of ethanol from lignocellulosic biomass sources. Although they aggressively ferment hexoses, it has long been thought that native Saccharomyces cerevisiae strains cannot grow fermentatively or non-fermentatively on xylose. Population surveys have uncovered a few naturally occurring strains that are weakly xylose-positive, and some S. cerevisiae have been genetically engineered to ferment xylose, but no strain, either natural or engineered, has yet been reported to ferment xylose as efficiently as glucose. Here, we used a medium-throughput screen to identify Saccharomyces strains that can increase in optical density when xylose is presented as the sole carbon source. We identified 38 strains that have this xylose utilization phenotype, including strains of S. cerevisiae, other sensu stricto members, and hybrids between them. All the S. cerevisiae xylose-utilizing strains we identified are wine yeasts, and for those that could produce meiotic progeny, the xylose phenotype segregates as a single gene trait. We mapped this gene by Bulk Segregant Analysis (BSA using tiling microarrays and high-throughput sequencing. The gene is a putative xylitol dehydrogenase, which we name XDH1, and is located in the subtelomeric region of the right end of chromosome XV in a region not present in the S288c reference genome. We further characterized the xylose phenotype by performing gene expression microarrays and by genetically dissecting the endogenous Saccharomyces xylose pathway. We have demonstrated that natural S. cerevisiae yeasts are capable of utilizing xylose as the sole carbon source, characterized the genetic basis for this trait as well as the endogenous xylose utilization pathway, and demonstrated the feasibility of BSA using high-throughput sequencing.

Optimization of ordered plasmid assembly by gap repair in Saccharomyces cerevisiae

DEFF Research Database (Denmark)

Eckert-Boulet, Nadine Valerie; Pedersen, Mette Louise; Krogh, Berit Olsen

2012-01-01

Combinatorial genetic libraries are powerful tools for diversifying and optimizing biomolecules. The process of library assembly is a major limiting factor for library complexity and quality. Gap repair by homologous recombination in Saccharomyces cerevisiae can facilitate in vivo assembly of DNA...

The use of genetically modified Saccharomyces cerevisiae strains in the wine industry.

Science.gov (United States)

Schuller, Dorit; Casal, Margarida

2005-08-01

In recent decades, science and food technology have contributed at an accelerated rate to the introduction of new products to satisfy nutritional, socio-economic and quality requirements. With the emergence of modern molecular genetics, the industrial importance of Saccharomyces cerevisiae, is continuously extended. The demand for suitable genetically modified (GM) S. cerevisiae strains for the biofuel, bakery and beverage industries or for the production of biotechnological products (e.g. enzymes, pharmaceutical products) will continuously grow in the future. Numerous specialised S. cerevisiae wine strains were obtained in recent years, possessing a wide range of optimised or novel oenological properties, capable of satisfying the demanding nature of modern winemaking practise. The unlocking of transcriptome, proteome and metabolome complexities will contribute decisively to the knowledge about the genetic make-up of commercial yeast strains and will influence wine strain improvement via genetic engineering. The most relevant advances regarding the importance and implications of the use of GM yeast strains in the wine industry are discussed in this mini-review. In this work, various aspects are considered including the strategies used for the construction of strains with respect to current legislation requirements, the environmental risk evaluations concerning the deliberate release of genetically modified yeast strains, the methods for detection of recombinant DNA and protein that are currently under evaluation, and the reasons behind the critical public perception towards the application of such strains.

Enhanced kefiran production by mixed culture of Lactobacillus kefiranofaciens and Saccharomyces cerevisiae.

Science.gov (United States)

Cheirsilp, Benjamas; Shimizu, Hiroshi; Shioya, Suteaki

2003-01-09

In a batch mixed culture of Lactobacillus kefiranofaciens and Saccharomyces cerevisiae, which could assimilate lactic acid, cell growth and kefiran production rates of L. kefiranofaciens significantly increased, compared with those in pure cultures. The kefiran production rate was 36 mg l(-1) h(-1) in the mixed culture under the anaerobic condition, which was greater than that in the pure culture (24 mg l(-1) h(-1)). Under the aerobic condition, a more intensive interaction between these two strains was observed and higher kefiran production rate (44 mg l(-1) h(-1)) was obtained compared with that under the anaerobic condition. Kefiran production was further enhanced by an addition of fresh medium in the fed-batch mixed culture. In the fed-batch mixed culture, a final kefiran concentration of 5.41 g l(-1) was achieved at 87 h, thereby attaining the highest productivity at 62 mg l(-1) h(-1). Simulation study considered the reduction of lactic acid in pure culture was performed to estimate the additional effect of coculture with S. cerevisiae. Slightly higher cell growth and kefiran production rates in the mixed culture than those expected from pure culture by simulation were observed. These results suggest that coculture of L. kefiranofaciens and S. cerevisiae not only reduces the lactic acid concentration by consumption but also stimulates cell growth and kefiran production of L. kefiranofaciens.

Intracellular Signal Triggered by Cholera Toxin in Saccharomyces boulardii and Saccharomyces cerevisiae

Science.gov (United States)

Brandão, Rogelio L.; Castro, Ieso M.; Bambirra, Eduardo A.; Amaral, Sheila C.; Fietto, Luciano G.; Tropia, Maria José M.; Neves, Maria José; Dos Santos, Raquel G.; Gomes, Newton C. M.; Nicoli, Jacques R.

1998-01-01

As is the case for Saccharomyces boulardii, Saccharomyces cerevisiae W303 protects Fisher rats against cholera toxin (CT). The addition of glucose or dinitrophenol to cells of S. boulardii grown on a nonfermentable carbon source activated trehalase in a manner similar to that observed for S. cerevisiae. The addition of CT to the same cells also resulted in trehalase activation. Experiments performed separately on the A and B subunits of CT showed that both are necessary for activation. Similarly, the addition of CT but not of its separate subunits led to a cyclic AMP (cAMP) signal in both S. boulardii and S. cerevisiae. These data suggest that trehalase stimulation by CT probably occurred through the cAMP-mediated protein phosphorylation cascade. The requirement of CT subunit B for both the cAMP signal and trehalase activation indicates the presence of a specific receptor on the yeasts able to bind to the toxin, a situation similar to that observed for mammalian cells. This hypothesis was reinforced by experiments with 125I-labeled CT showing specific binding of the toxin to yeast cells. The adhesion of CT to a receptor on the yeast surface through the B subunit and internalization of the A subunit (necessary for the cAMP signal and trehalase activation) could be one more mechanism explaining protection against the toxin observed for rats treated with yeasts. PMID:9464394

Expression of an Aspergillus niger Phytase Gene (phyA) in Saccharomyces cerevisiae

Science.gov (United States)

Han, Yanming; Wilson, David B.; Lei, Xin gen

1999-01-01

Phytase improves the bioavailability of phytate phosphorus in plant foods to humans and animals and reduces phosphorus pollution of animal waste. Our objectives were to express an Aspergillus niger phytase gene (phyA) in Saccharomyces cerevisiae and to determine the effects of glycosylation on the phytase’s activity and thermostability. A 1.4-kb DNA fragment containing the coding region of the phyA gene was inserted into the expression vector pYES2 and was expressed in S. cerevisiae as an active, extracellular phytase. The yield of total extracellular phytase activity was affected by the signal peptide and the medium composition. The expressed phytase had two pH optima (2 to 2.5 and 5 to 5.5) and a temperature optimum between 55 and 60°C, and it cross-reacted with a rabbit polyclonal antibody against the wild-type enzyme. Due to the heavy glycosylation, the expressed phytase had a molecular size of approximately 120 kDa and appeared to be more thermostable than the commercial enzyme. Deglycosylation of the phytase resulted in losses of 9% of its activity and 40% of its thermostability. The recombinant phytase was effective in hydrolyzing phytate phosphorus from corn or soybean meal in vitro. In conclusion, the phyA gene was expressed as an active, extracellular phytase in S. cerevisiae, and its thermostability was affected by glycosylation. PMID:10223979

Saccharomyces cerevisiae GTPase complex: Gtr1p-Gtr2p regulates cell-proliferation through Saccharomyces cerevisiae Ran-binding protein, Yrb2p

International Nuclear Information System (INIS)

Wang Yonggang; Nakashima, Nobutaka; Sekiguchi, Takeshi; Nishimoto, Takeharu

2005-01-01

A Gtr1p GTPase, the GDP mutant of which suppresses both temperature-sensitive mutants of Saccharomyces cerevisiae RanGEF/Prp20p and RanGAP/Rna1p, was presently found to interact with Yrb2p, the S. cerevisiae homologue of mammalian Ran-binding protein 3. Gtr1p bound the Ran-binding domain of Yrb2p. In contrast, Gtr2p, a partner of Gtr1p, did not bind Yrb2p, although it bound Gtr1p. A triple mutant: yrb2Δ gtr1Δ gtr2Δ was lethal, while a double mutant: gtr1Δ gtr2Δ survived well, indicating that Yrb2p protected cells from the killing effect of gtr1Δ gtr2Δ. Recombinant Gtr1p and Gtr2p were purified as a complex from Escherichia coli. The resulting Gtr1p-Gtr2p complex was comprised of an equal amount of Gtr1p and Gtr2p, which inhibited the Rna1p/Yrb2 dependent RanGAP activity. Thus, the Gtr1p-Gtr2p cycle was suggested to regulate the Ran cycle through Yrb2p

Apuntes sobre esporotricosis

OpenAIRE

Londoño, Fabio

2011-01-01

Se hace una breve reseña histórica de las primeras comunicaciones sobre esporotricosis. Se destaca la amplia difusión de la enfermedad en nuestro país. 3. Se hace notar la no existencia de datos bibliográficos sobre formas extracutáneas. 4. Se llama la atención sobre la eficaz ayuda de la intradermo-reacción con esporotriquina en el diagnóstico de la enfermedad. 5- Se comunica un caso de esporotricosis verrugosa tratado con anfotericin B, con excelentes resultados

Apuntes sobre esporotricosis

Directory of Open Access Journals (Sweden)

Fabio Londoño

1960-01-01

Full Text Available Se hace una breve reseña histórica de las primeras comunicaciones sobre esporotricosis. Se destaca la amplia difusión de la enfermedad en nuestro país. 3. Se hace notar la no existencia de datos bibliográficos sobre formas extracutáneas. 4. Se llama la atención sobre la eficaz ayuda de la intradermo-reacción con esporotriquina en el diagnóstico de la enfermedad. 5- Se comunica un caso de esporotricosis verrugosa tratado con anfotericin B, con excelentes resultados

Huysmans e Gonzaga Duque: transposições de arte em textos franceses e brasileiros do Simbolismo

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André Soares Vieira

2013-12-01

Full Text Available Este ensaio pretende refletir sobre alguns processos de tradução de obras picturais transpostas para textos críticos e literários. O processo de transposição escrita da pintura será examinado segundo uma análise do discurso sobre arte produzido pelo escritor e crítico brasileiro Gonzaga Duque (1863-1911 e pelo romancista e também crítico de arte francês Joris-Karl Huysmans (1848- 1907. O objetivo é o de mapear, através de obras dos pintores Matthias Grünewald (1470-1528 e Félicien Rops (1833-1898, alguns modos de transferência entre a arte pictórica e os textos críticos e literários, tomando-se por base, sobretudo, os estudos de Françoise Lucbert.

SOBRE OS FUNDAMENTOS DA ARQUITETURA DA INFORMAÇÃO

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Alfram Roberto Rodrigues de Albuquerque

2011-10-01

Full Text Available Expõe-se o estado atual da disciplina Arquitetura da Informação quanto a problemática terminológica da definição do campo de estudo, apresentando-se argumentos para uma definição de Arquitetura da Informação de uma forma ampla na qual os usos correntes dessa expressão sejam vistos como especializações. Defende-se uma definição com a utilização de um conjunto de propriedades mínimas cujas interações levam a uma terminologia formal e cuja abstração leva a uma definição formal do conceito que emprega a linguagem de morfismos da Teoria das Categorias. Trata-se de um recorte de alguns dos resultados obtidos na tese de doutoramento de um dos autores, defendida em setembro de 2010. O contexto da pesquisa é exposto e alguns dos resultados obtidos são delineados.

Industrial systems biology of Saccharomyces cerevisiae enables novel succinic acid cell factory.

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José Manuel Otero

Full Text Available Saccharomyces cerevisiae is the most well characterized eukaryote, the preferred microbial cell factory for the largest industrial biotechnology product (bioethanol, and a robust commerically compatible scaffold to be exploitted for diverse chemical production. Succinic acid is a highly sought after added-value chemical for which there is no native pre-disposition for production and accmulation in S. cerevisiae. The genome-scale metabolic network reconstruction of S. cerevisiae enabled in silico gene deletion predictions using an evolutionary programming method to couple biomass and succinate production. Glycine and serine, both essential amino acids required for biomass formation, are formed from both glycolytic and TCA cycle intermediates. Succinate formation results from the isocitrate lyase catalyzed conversion of isocitrate, and from the α-keto-glutarate dehydrogenase catalyzed conversion of α-keto-glutarate. Succinate is subsequently depleted by the succinate dehydrogenase complex. The metabolic engineering strategy identified included deletion of the primary succinate consuming reaction, Sdh3p, and interruption of glycolysis derived serine by deletion of 3-phosphoglycerate dehydrogenase, Ser3p/Ser33p. Pursuing these targets, a multi-gene deletion strain was constructed, and directed evolution with selection used to identify a succinate producing mutant. Physiological characterization coupled with integrated data analysis of transcriptome data in the metabolically engineered strain were used to identify 2(nd-round metabolic engineering targets. The resulting strain represents a 30-fold improvement in succinate titer, and a 43-fold improvement in succinate yield on biomass, with only a 2.8-fold decrease in the specific growth rate compared to the reference strain. Intuitive genetic targets for either over-expression or interruption of succinate producing or consuming pathways, respectively, do not lead to increased succinate. Rather, we

Recycling carbon dioxide during xylose fermentation by engineered Saccharomyces cerevisiae

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In this study, we introduced the ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and phosphoribulokinase (PRK) into an engineered S. cerevisiae (SR8) harboring the XR/XDH pathway and up-regulated PPP 10, to enable CO2 recycling through a synthetic rPPP during xylose fermentation (Fig. 1). ...

Anethole induces apoptotic cell death accompanied by reactive oxygen species production and DNA fragmentation in Aspergillus fumigatus and Saccharomyces cerevisiae.

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Fujita, Ken-Ichi; Tatsumi, Miki; Ogita, Akira; Kubo, Isao; Tanaka, Toshio

2014-02-01

trans-Anethole (anethole), a major component of anise oil, has a broad antimicrobial spectrum, and antimicrobial activity that is weaker than that of other antibiotics on the market. When combined with polygodial, nagilactone E, and n-dodecanol, anethole has been shown to possess significant synergistic antifungal activity against a budding yeast, Saccharomyces cerevisiae, and a human opportunistic pathogenic yeast, Candida albicans. However, the antifungal mechanism of anethole has not been completely determined. We found that anethole stimulated cell death of a human opportunistic pathogenic fungus, Aspergillus fumigatus, in addition to S. cerevisiae. The anethole-induced cell death was accompanied by reactive oxygen species production, metacaspase activation, and DNA fragmentation. Several mutants of S. cerevisiae, in which genes related to the apoptosis-initiating execution signals from mitochondria were deleted, were resistant to anethole. These results suggest that anethole-induced cell death could be explained by oxidative stress-dependent apoptosis via typical mitochondrial death cascades in fungi, including A. fumigatus and S. cerevisiae. © 2014 FEBS.

Tenossinovite e sinovite do primeiro compartimento extensor do punho: o que o ultrassonografista precisa saber

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Carlos Frederico Arend

2012-08-01

Full Text Available A tenossinovite do primeiro compartimento extensor é uma enfermidade frequente, cercada por mitos. O objetivo deste artigo é revisar cientificamente alguns dos aspectos mais pertinentes ao ultrassonografista sobre sua terminologia, fisiopatogenia, diagnóstico e acompanhamento.

Elimination of Glycerol Production in Anaerobic Cultures of a Saccharomyces cerevisiae Strain Engineered To Use Acetic Acid as an Electron Acceptor

NARCIS (Netherlands)

Medina, V.G.; Almering, M.J.H.; Van Maris, A.J.A.; Pronk, J.T.

2009-01-01

In anaerobic cultures of wild-type Saccharomyces cerevisiae, glycerol production is essential to reoxidize NADH produced in biosynthetic processes. Consequently, glycerol is a major by-product during anaerobic production of ethanol by S. cerevisiae, the single largest fermentation process in

H. guilliermondii impacts growth kinetics and metabolic activity of S. cerevisiae: the role of initial nitrogen concentration.

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Lage, Patrícia; Barbosa, Catarina; Mateus, Beatriz; Vasconcelos, Isabel; Mendes-Faia, Arlete; Mendes-Ferreira, Ana

2014-02-17

Non-Saccharomyces yeasts include different species which comprise an ecologically and biochemically diverse group capable of altering fermentation dynamics and wine composition and flavour. In this study, single- and mixed-culture of Hanseniaspora guilliermondii and Saccharomyces cerevisiae were used to ferment natural grape-juice, under two nitrogen regimes. In single-culture the strain H. guilliermondii failed to complete total sugar breakdown even though the nitrogen available has not been a limiting factor of its growth or fermentative activity. In mixed-culture, that strain negatively interfered with the growth and fermentative performance of S. cerevisiae, resulting in lower fermentation rate and longer fermentation length, irrespective of the initial nitrogen concentration. The impact of co-inoculation on the volatile compounds profile was more evident in the wines obtained from DAP-supplemented musts, characterised by increased levels of ethyl and acetate esters, associated with fruity and floral character of wines. Moreover, the levels of fatty acids and sulphur compounds which are responsible for unpleasant odours that depreciate wine sensory quality were significantly lower. Accordingly, data obtained suggests that the strain H. guilliermondii has potential to be used as adjunct of S. cerevisiae in wine industry, although possible interactions with S. cerevisiae still need to be elucidated. Copyright © 2013 Elsevier B.V. All rights reserved.

Applied systems biology - vanillin production in Saccharomyces cerevisiae

OpenAIRE

Strucko, Tomas; Eriksen, Jens Christian; Nielsen, J.; Mortensen, Uffe Hasbro

2012-01-01

Vanillin is the most important aroma compound based on market value, and natural vanillin is extracted from the cured seed pods of the Vanilla orchid. Most of the world’s vanillin, however, is obtained by chemical synthesis from petrochemicals or wood pulp lignins. As an alternative, de novo biosynthesis of vanillin in baker’s yeast Saccharomyces cerevisiae was recently demonstrated by successfully introducing the metabolic pathway for vanillin production in yeast. Nevertheless, the amount of...

Biosynthesis and engineering of kaempferol in Saccharomyces cerevisiae

OpenAIRE

Duan, Lijin; Ding, Wentao; Liu, Xiaonan; Cheng, Xiaozhi; Cai, Jing; Hua, Erbing; Jiang, Huifeng

2017-01-01

Background Kaempferol is a flavonol with broad bioactivity of anti-oxidant, anti-cancer, anti-diabetic, anti-microbial, cardio-protective and anti-asthma. Microbial synthesis of kaempferol is a promising strategy because of the low content in primary plant source. Methods In this study, the biosynthesis pathway of kaempferol was constructed in the budding yeast Saccharomyces cerevisiae to produce kaempferol de novo, and several biological measures were taken for high production. Results First...

Hurdle technology applied to prickly pear beverages for inhibiting Saccharomyces cerevisiae and Escherichia coli.

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García-García, R; Escobedo-Avellaneda, Z; Tejada-Ortigoza, V; Martín-Belloso, O; Valdez-Fragoso, A; Welti-Chanes, J

2015-06-01

The effect of pH reduction (from 6·30-6·45 to 4·22-4·46) and the addition of antimicrobial compounds (sodium benzoate and potassium sorbate) on the inhibition of Saccharomyces cerevisiae and Escherichia coli in prickly pear beverages formulated with the pulp and peel of Villanueva (V, Opuntia albicarpa) and Rojo Vigor (RV, Opuntia ficus-indica) varieties during 14 days of storage at 25°C, was evaluated. RV variety presented the highest microbial inhibition. By combining pH reduction and preservatives, reductions of 6·2-log10 and 2·3-log10 for E. coli and S. cerevisiae were achieved respectively. Due to the low reduction of S. cerevisiae, pulsed electric fields (PEF) (11-15 μs/25-50 Hz/27-36 kV cm(-1)) was applied as another preservation factor. The combination of preservatives, pH reduction and PEF at 13-15 μs/25-50 Hz for V variety, and 11 μs/50 Hz, 13-15 μs/25-50 Hz for RV, had a synergistic effect on S. cerevisiae inhibition, achieving at least 3·4-log10 of microbial reduction immediately after processing, and more than 5-log10 at fourth day of storage at 25°C maintained this reduction during 21 days of storage (P > 0·05). Hurdle technology using PEF in combination with other factors is adequate to maintain stable prickly pear beverages during 21 days/25°C. Significance and impact of the study: Prickly pear is a fruit with functional value, with high content of nutraceuticals and antioxidant activity. Functional beverages formulated with the pulp and peel of this fruit represent an alternative for its consumption. Escherichia coli and Saccharomyces cerevisiae are micro-organisms that typically affect fruit beverage quality and safety. The food industry is looking for processing technologies that maintain quality without compromising safety. Hurdle technology, including pulsed electric fields (PEF) could be an option to achieve this. The combination of PEF, pH reduction and preservatives is an alternative to obtain safe and minimally processed

O ambiente macroeconômico e o bem-estar social: uma revisão bibliográfica sobre relações e controvérsias

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Ricardo Agostini Martini

2013-08-01

Full Text Available De acordo com estudos recentes, sabe-se que os choques nas variáveis agregadas implicam em impactos diferenciados sobre o sistema econômico, afetando mais alguns setores ou agentes do que outros de acordo com suas as características. Teoricamente, os mecanismos que diferenciam os efeitos dos choques entre os agentes e os setores da economia são as variações de preços relativos dos diferentes produtos e fatores de produção, a variação da demanda por mão de obra, as características dos trabalhadores e o direcionamento das políticas públicas vigentes. Nesse sentido, mediante uma revisão bibliográfica teórica e empírica sobre a relação entre o desempenho macroeconômico dos países e o bem-estar social, o objetivo do presente artigo é procurar respostas para três questões. Primeira: quais são os agentes econômicos que mais sofrem as recessões? Segunda: quais são os agentes que mais se beneficiam do crescimento econômico? Terceira: quais são as políticas relacionadas com a administração macroeconômica dos problemas sociais?

Isolation of beta-glucan from the cell wall of Saccharomyces cerevisiae.

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Shokri, Hojjatollah; Asadi, Farzad; Khosravi, Ali Reza

2008-03-20

Beta-glucan, one of the major cell wall components of Saccharomyces cerevisiae (S. cerevisiae), has been found to enhance immune functions. At present study, we developed an optimal procedure to extract and purify beta-glucan. At first, yeast cells were grown in sabouraud dextrose agar and then cultured in yeast extract-peptone-glucose (YPG) broth. After incubation, cells were harvested, washed and disrupted by means of sonication method. The obtained cell walls were used to prepare alkali-soluble beta-glucan (glucan-S1). In this regard, 2% sodium hydroxide (NaOH) and 3% acetic acid were used in alkaline-acid extraction, respectively. This preparation contained 2.4% protein. In the next step, DEAE sephacel chromatography was used to remove remaining proteins (glucan-S2). Subsequently this preparation was applied into concanavalin-A sepharose column to remove manann. Finally, beta-glucan free of mannoprotein complexes was prepared (glucan-S3).

Os docentes de Biblioteconomia, Documentação e Ciência da Informação no Brasil: alguns resultados de estudo exploratório sobre as representações da profissão bibliotecária

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Maria Tereza Machado Teles Walter

2009-10-01

Full Text Available http://dx.doi.org/10.5007/1518-2924.2009v14n28p01 As representações da profissão bibliotecária são analisadas sob a perspectiva dos docentes, em estudo exploratório. Os dados parciais apresentados refletem a opinião dos entrevistados acerca de sua percepção dos alunos, do curso, da profissão e dos organismos representativos dos bibliotecários. De modo geral, os professores manifestaram que os alunos não entram nos cursos por vocação, são originários de classes socioeconômicas menos favorecidas, possuem formação básica frágil e não estão interessados na carreira, mas somente no diploma. Apontaram problemas decorrentes da forma como são conduzidos os cursos, do modo como alguns professores atuam e de como trabalham para que os alunos adquiram conhecimentos e mudem suas atitudes.

Algumas considerações sobre o desenvolvimento da atividade de leitura e a constituição do leitor surdo/Some aspects on the development of the activity of reading and the constitution of the deaf reader

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Heloísa Andréia Vicente de Matos

2006-01-01

Full Text Available Este trabalho aponta alguns aspectos teóricos sobre a questão da leitura e seus desdobramentos e, por conseguinte, sobre os aspectos relacionados à constituição do leitor também nas condições da surdez. Do mesmo modo, destaca questões do letramento e as implicações desse processo na constituição do leitor Surdo, também através de narrativas de sujeitos adultos (com pouca influência da oralização e relativa proficiência na leitura do Português, no presente sobre seus movimentos de formação, configurados na noção de espaço e tempo construídos pela memória dos mesmos. This paper points some theoretical aspects on the question of the reading and its unfoldings and, therefore, on the aspects related to the constitution of the reader also in the conditions of the deafness. In a similar way, it detaches questions of the literacy and the implications of this process in the constitution of the Deaf reader, also through narratives of adult deaf people (with little influence of the oralism and relative proficiency in the reading of the Portuguese, at the current moment on its movements of formation, configured in the notion of space and time constructed by the memory of the same ones.

O consultor e o manejo de clima grupal

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Edela Lanzer Pereira de Souza

Full Text Available O trabalho aborda o manejo de clima como atividade deliberada, passível de treinamento. Requer capacitação conceitual, técnica e humana. Inicialmente é feita uma resenha bibliográfica sobre as abordagens de clima. Depois são analisados alguns momentos críticos, a saber: os contatos iniciais, a manutenção do clima, depressões e conflitos, brincadeiras e risos. Finalmente são tratados alguns estereótipos profissionais que dificultam a empatia entre consultor e clientes.

Evaluation of Brachypodium distachyon L-Tyrosine Decarboxylase Using L-Tyrosine Over-Producing Saccharomyces cerevisiae.

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Shuhei Noda

Full Text Available To demonstrate that herbaceous biomass is a versatile gene resource, we focused on the model plant Brachypodium distachyon, and screened the B. distachyon for homologs of tyrosine decarboxylase (TDC, which is involved in the modification of aromatic compounds. A total of 5 candidate genes were identified in cDNA libraries of B. distachyon and were introduced into Saccharomyces cerevisiae to evaluate TDC expression and tyramine production. It is suggested that two TDCs encoded in the transcripts Bradi2g51120.1 and Bradi2g51170.1 have L-tyrosine decarboxylation activity. Bradi2g51170.1 was introduced into the L-tyrosine over-producing strain of S. cerevisiae that was constructed by the introduction of mutant genes that promote deregulated feedback inhibition. The amount of tyramine produced by the resulting transformant was 6.6-fold higher (approximately 200 mg/L than the control strain, indicating that B. distachyon TDC effectively converts L-tyrosine to tyramine. Our results suggest that B. distachyon possesses enzymes that are capable of modifying aromatic residues, and that S. cerevisiae is a suitable host for the production of L-tyrosine derivatives.

Gains and Losses of Transcription Factor Binding Sites in Saccharomyces cerevisiae and Saccharomyces paradoxus

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Schaefke, Bernhard; Wang, Tzi-Yuan; Wang, Chuen-Yi; Li, Wen-Hsiung

2015-01-01

Gene expression evolution occurs through changes in cis- or trans-regulatory elements or both. Interactions between transcription factors (TFs) and their binding sites (TFBSs) constitute one of the most important points where these two regulatory components intersect. In this study, we investigated the evolution of TFBSs in the promoter regions of different Saccharomyces strains and species. We divided the promoter of a gene into the proximal region and the distal region, which are defined, respectively, as the 200-bp region upstream of the transcription starting site and as the 200-bp region upstream of the proximal region. We found that the predicted TFBSs in the proximal promoter regions tend to be evolutionarily more conserved than those in the distal promoter regions. Additionally, Saccharomyces cerevisiae strains used in the fermentation of alcoholic drinks have experienced more TFBS losses than gains compared with strains from other environments (wild strains, laboratory strains, and clinical strains). We also showed that differences in TFBSs correlate with the cis component of gene expression evolution between species (comparing S. cerevisiae and its sister species Saccharomyces paradoxus) and within species (comparing two closely related S. cerevisiae strains). PMID:26220934

Transcriptome-based characterization of interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus in lactose-grown chemostat cocultures.

Science.gov (United States)

Mendes, Filipa; Sieuwerts, Sander; de Hulster, Erik; Almering, Marinka J H; Luttik, Marijke A H; Pronk, Jack T; Smid, Eddy J; Bron, Peter A; Daran-Lapujade, Pascale

2013-10-01

Mixed populations of Saccharomyces cerevisiae yeasts and lactic acid bacteria occur in many dairy, food, and beverage fermentations, but knowledge about their interactions is incomplete. In the present study, interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus, two microorganisms that co-occur in kefir fermentations, were studied during anaerobic growth on lactose. By combining physiological and transcriptome analysis of the two strains in the cocultures, five mechanisms of interaction were identified. (i) Lb. delbrueckii subsp. bulgaricus hydrolyzes lactose, which cannot be metabolized by S. cerevisiae, to galactose and glucose. Subsequently, galactose, which cannot be metabolized by Lb. delbrueckii subsp. bulgaricus, is excreted and provides a carbon source for yeast. (ii) In pure cultures, Lb. delbrueckii subsp. bulgaricus grows only in the presence of increased CO2 concentrations. In anaerobic mixed cultures, the yeast provides this CO2 via alcoholic fermentation. (iii) Analysis of amino acid consumption from the defined medium indicated that S. cerevisiae supplied alanine to the bacterium. (iv) A mild but significant low-iron response in the yeast transcriptome, identified by DNA microarray analysis, was consistent with the chelation of iron by the lactate produced by Lb. delbrueckii subsp. bulgaricus. (v) Transcriptome analysis of Lb. delbrueckii subsp. bulgaricus in mixed cultures showed an overrepresentation of transcripts involved in lipid metabolism, suggesting either a competition of the two microorganisms for fatty acids or a response to the ethanol produced by S. cerevisiae. This study demonstrates that chemostat-based transcriptome analysis is a powerful tool to investigate microbial interactions in mixed populations.

Analysis of the RNA Content of the Yeast "Saccharomyces Cerevisiae"

Science.gov (United States)

Deutch, Charles E.; Marshall, Pamela A.

2008-01-01

In this article, the authors describe an interconnected set of relatively simple laboratory experiments in which students determine the RNA content of yeast cells and use agarose gel electrophoresis to separate and analyze the major species of cellular RNA. This set of experiments focuses on RNAs from the yeast "Saccharomyces cerevisiae", a…

Data on dynamic study of cytoophidia in Saccharomyces cerevisiae

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Hui Li

2016-09-01

Full Text Available The data in this paper are related to the research article entitled “Filamentation of metabolic enzymes in Saccharomyces cerevisiae” Q.J. Shen et al. (2016 [1]. Cytoophidia are filamentous structures discovered in fruit flies (doi:10.1016/S1673-8527(0960046-1 J.L. Liu (2010 [2], bacteria (doi:10.1038/ncb2087 M. Ingerson-Mahar et al. (2010 [3], yeast (doi:10.1083/jcb.201003001; doi:10.1242/bio.20149613 C. Noree et al. (2010 and J. Zhang, L. Hulme, J.L. Liu (2014 [4,5] and human cells (doi:10.1371/journal.pone.0029690; doi:10.1016/j.jgg.2011.08.004 K. Chen et al. (2011 and W.C. Carcamo et al. (2011 ( [6,7]. However, there is little research on the motility of the cytoophidia. Here we selected cytoophidia formed by 6 filament-forming proteins in the budding yeast S. cerevisiae, and performed living-cell imaging of cells expressing the proteins fused with GFP. The dynamic features of the six types of cytoophidia were analyzed. In the data, both raw movies and analysed results of the dynamics of cytoophidia are presented. Keywords: Saccharomyces cerevisiae, CTP synthase, Cytoophidium, Metabolism, Filamentation

Omics analysis of acetic acid tolerance in Saccharomyces cerevisiae.

Science.gov (United States)

Geng, Peng; Zhang, Liang; Shi, Gui Yang

2017-05-01

Acetic acid is an inhibitor in industrial processes such as wine making and bioethanol production from cellulosic hydrolysate. It causes energy depletion, inhibition of metabolic enzyme activity, growth arrest and ethanol productivity losses in Saccharomyces cerevisiae. Therefore, understanding the mechanisms of the yeast responses to acetic acid stress is essential for improving acetic acid tolerance and ethanol production. Although 329 genes associated with acetic acid tolerance have been identified in the Saccharomyces genome and included in the database ( http://www.yeastgenome.org/observable/resistance_to_acetic_acid/overview ), the cellular mechanistic responses to acetic acid remain unclear in this organism. Post-genomic approaches such as transcriptomics, proteomics, metabolomics and chemogenomics are being applied to yeast and are providing insight into the mechanisms and interactions of genes, proteins and other components that together determine complex quantitative phenotypic traits such as acetic acid tolerance. This review focuses on these omics approaches in the response to acetic acid in S. cerevisiae. Additionally, several novel strains with improved acetic acid tolerance have been engineered by modifying key genes, and the application of these strains and recently acquired knowledge to industrial processes is also discussed.

Estudio de nuevas levaduras Killer "Saccharomyces cerevisiae" y "Torulaspora delbrueckii" para elaborar vinos tranquilos y espumosos

OpenAIRE

Velázquez Molinero, Rocío

2016-01-01

Se analizan dos nuevos tipos de levaduras vínicas killer de amplio espectro antifúngico: Sacharomyces cerevisiae Klus y Torulaspora delbrueckii Kbarr. Ambas matan a todos los tipos de levaduras S. cerevisiae conocidos, killer y sensibles, además de muchas otras especies de levaduras no-Saccharomyces. El receptor de la pared celular de las levaduras sensibles a ambas toxinas parece ser el beta-glucano. El fenotipo killer de estas levaduras está codificado en virus de dsRNA de tamaño mediano, M...

Investigation of the effect of water exposed to nonequilibrium contact plasma onto saccharomyces cerevisiae yeast

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S. Mykolenko

2015-05-01

Full Text Available Introduction. Additional treatment of water by nonequilibrium contact plasma allows improving consumer characteristics of bakery goods considerably. Determination of the effect of plasma-chemically activated water on morphological, cultural and physiological properties of Saccharomyces cerevisiae yeast is important from the technological point of view. Materials and Methods. Experimental investigations were carried out in the conditions of bacteriological laboratory by seeding the culture of yeasts of ТМ “Lvivski” and “Kryvorizki” on Sabouraud dense liquid nutrient media. The quantity of viable cells of microorganisms was determined by the method of Gould sector seeds. Morphology of the yeast was investigated by phase-contrast microscopy. Biotechnological properties of yeasts were determined on Giss media. Results. The paper establishes the effect of water exposed to nonequilibrium contact plasma on the sensitivity of Saccharomyces cerevisiae and shows absence of suppressive action of treated water with regard to cultural properties of microorganisms. The experiments prove that with the use of plasma-chemically activated water morphological characteristics and biochemical properties of bakery yeasts produced by Lviv and Kryvyi Rig yeast plants are preserved. Culturing of Saccharomyces cerevisiae yeast on the nutrient media prepared with the use of water exposed to nonequilibrium contact plasm resulted in 6,5–15 times’ increase in quantity of viable microorganisms compared with the control on the mains drinking water. Conclusions. Physiological properties of Saccharomyces cerevisiae yeast improved owing to use water exposed to nonequilibrium contact plasma. Results of investigations are recommended for using in yeast production and bread making.

Metabolic alterations during ascosporogenesis of Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Carvalho, Sandra; Nadkarni, G.B.

1977-01-01

Sporulation of S. cerevisiae has been shown to alter the profiles of enzymes involved in gluconeogenesis and glycolysis. The enhancement in the levels of total cellular carbohydrates could be correlated with the enhancement in fructose 1,6-diphosphatase and trehalose-phosphate synthetase. The latter activity could account for the 15-fold increase in trehalose levels in sporulating cells. Glucose-6-phosphatase, pyruvate kinase and phosphofructokinase showed continuous decline during ascosporogenesis. The relative incorporation of radioactivity from possible precursors of gluconeogenesis indicated that acetate-2- 14 C alone could contribute to carbohydrate synthesis. (author)

Heterologous expression of a rice metallothionein isoform (OsMTI-1b in Saccharomyces cerevisiae enhances cadmium, hydrogen peroxide and ethanol tolerance

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Zahra Ansarypour

Full Text Available Abstract Metallothioneins are a superfamily of low-molecular-weight, cysteine (Cys-rich proteins that are believed to play important roles in protection against metal toxicity and oxidative stress. The main purpose of this study was to investigate the effect of heterologous expression of a rice metallothionein isoform (OsMTI-1b on the tolerance of Saccharomyces cerevisiae to Cd2+, H2O2 and ethanol stress. The gene encoding OsMTI-1b was cloned into p426GPD as a yeast expression vector. The new construct was transformed to competent cells of S. cerevisiae. After verification of heterologous expression of OsMTI-1b, the new strain and control were grown under stress conditions. In comparison to control strain, the transformed S. cerevisiae cells expressing OsMTI-1b showed more tolerance to Cd2+ and accumulated more Cd2+ ions when they were grown in the medium containing CdCl2. In addition, the heterologous expression of GST-OsMTI-1b conferred H2O2 and ethanol tolerance to S. cerevisiae cells. The results indicate that heterologous expression of plant MT isoforms can enhance the tolerance of S. cerevisiae to multiple stresses.

REFLEXÕES SOBRE AS IDENTIDADES-CONSUMO NA AMÉRICA LATINA SOBRE A ÓTICA DA ATIVIDADE TURÍSTICA

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Denio Santos Azevedo

2014-06-01

Full Text Available A atividade turística relaciona-se, diante da sua complexidade, com elementos midiáticos que estimulam o consumo de determinados destinos e culturas. Os planejadores turísticos transformaram e continuam transformando cidades, a história, a memória e o patrimônio cultural material e imaterial de grupos sociais específicos, entendidos como elementos representativos das identidades, em atrativos turísticos, ou seja, em objetos de consumo. Tal fabricação possui como base de sustentação o planejamento turístico e a sua difusão se dá a partir das diferentes mídias utilizadas na promoção turística. Consumir as identidades-consumo é consumir simbolicamente o “outro” e tal prática gera “distinção” entre os grupos sociais, constrói imaginários e alimenta a “concorrência “inter-cidades” no mercado latino dos deslocamentos programados para fins turísticos. Neste sentido, os planejadores turísticos motivam os deslocamentos temporários por meio da possibilidade destes viajantes terem contato com outras culturas e conhecimentos, por meio do consumo simbólico dos elementos identitários do “outro”. É por meio do consumo simbólicos das representações identitárias de grupos sociais específicos que o turista ou visitante passa a identificar cidades e/ou países na promoção turística dos destinos. Considerando tais aspectos o presente estudo visa desenvolver reflexões sobre a relação entre o turismo, o turista e as identidades-consumo a partir de algumas observações sobre a promoção turística de algumas cidades latinas em sites de turismo aqui pesquisados. Observou-se, nos sites promocionais verificados, a representação de elementos considerados típicos de certos destinos turísticos como o Mariachi no México, a presença das comunidades guaranis na argentina, a exposição da gastronomia típica através dos Chivitos uruguaios, o Chorizo argentino, o Ceviche peruano, as Cachapas e as Arepas

Exploring the Saccharomyces cerevisiae Volatile Metabolome: Indigenous versus Commercial Strains

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Alves, Zélia; Melo, André; Figueiredo, Ana Raquel; Coimbra, Manuel A.; Gomes, Ana C.; Rocha, Sílvia M.

2015-01-01

Winemaking is a highly industrialized process and a number of commercial Saccharomyces cerevisiae strains are used around the world, neglecting the diversity of native yeast strains that are responsible for the production of wines peculiar flavours. The aim of this study was to in-depth establish the S. cerevisiae volatile metabolome and to assess inter-strains variability. To fulfill this objective, two indigenous strains (BT2652 and BT2453 isolated from spontaneous fermentation of grapes collected in Bairrada Appellation, Portugal) and two commercial strains (CSc1 and CSc2) S. cerevisiae were analysed using a methodology based on advanced multidimensional gas chromatography (HS-SPME/GC×GC-ToFMS) tandem with multivariate analysis. A total of 257 volatile metabolites were identified, distributed over the chemical families of acetals, acids, alcohols, aldehydes, ketones, terpenic compounds, esters, ethers, furan-type compounds, hydrocarbons, pyrans, pyrazines and S-compounds. Some of these families are related with metabolic pathways of amino acid, carbohydrate and fatty acid metabolism as well as mono and sesquiterpenic biosynthesis. Principal Component Analysis (PCA) was used with a dataset comprising all variables (257 volatile components), and a distinction was observed between commercial and indigenous strains, which suggests inter-strains variability. In a second step, a subset containing esters and terpenic compounds (C10 and C15), metabolites of particular relevance to wine aroma, was also analysed using PCA. The terpenic and ester profiles express the strains variability and their potential contribution to the wine aromas, specially the BT2453, which produced the higher terpenic content. This research contributes to understand the metabolic diversity of indigenous wine microflora versus commercial strains and achieved knowledge that may be further exploited to produce wines with peculiar aroma properties. PMID:26600152

Filosofia e interdisciplinaridade

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Márcio José Silveira Lima

Full Text Available Resumo Este texto pretende discutir alguns aspectos da interdisciplinaridade, tendo como fio condutor duas ideias centrais: primeiro, a importância do tema para os debates em torno da construção e da transmissão do conhecimento; segundo, a delimitação do campo de reflexão em que a contraposição à especialização ganha especial destaque. A intenção é questionar se a crítica à especialização não é contemporânea da própria consolidação do trabalho disciplinar e dos especialistas; e se essa crítica não teria aberto o caminho para os debates sobre a interdisciplinaridade. Nesse caso, escolheram-se três filósofos que parecem corroborar esse ponto de vista: Ortega y Gasset, Nietzsche e Adorno. Nos três casos, pode-se perceber a defesa da necessidade de abertura para um conhecimento mais amplo. Por fim, esboçam-se alguns pontos relevantes sobre a filosofia como uma disciplina e sobre o lugar que a crítica à especialização ocupa em sua reflexão, e conjectura-se sobre a abertura para o trabalho interdisciplinar.

Repurposing the Saccharomyces cerevisiae peroxisome for compartmentalizing multi-enzyme pathways

Energy Technology Data Exchange (ETDEWEB)

DeLoache, William [Univ. of California, Berkeley, CA (United States); Russ, Zachary [Univ. of California, Berkeley, CA (United States); Samson, Jennifer [Univ. of California, Berkeley, CA (United States); Dueber, John [Univ. of California, Berkeley, CA (United States)

2017-09-25

The peroxisome of Saccharomyces cerevisiae was targeted for repurposing in order to create a synthetic organelle that provides a generalizable compartment for engineered metabolic pathways. Compartmentalization of enzymes into organelles is a promising strategy for limiting metabolic crosstalk, improving pathway efficiency, and ultimately modifying the chemical environment to be distinct from that of the cytoplasm. We focused on the Saccharomyces cerevisiae peroxisome, as this organelle is not required for viability when grown on conventional media. We identified an enhanced peroxisomal targeting signal type 1 (PTS1) for rapidly importing non-native cargo proteins. Additionally, we performed the first systematic in vivo measurements of nonspecific metabolite permeability across the peroxisomal membrane using a polymer exclusion assay and characterized the size dependency of metabolite trafficking. Finally, we applied these new insights to compartmentalize a two-enzyme pathway in the peroxisome and characterize the expression regimes where compartmentalization leads to improved product titer. This work builds a foundation for using the peroxisome as a synthetic organelle, highlighting both promise and future challenges on the way to realizing this goal.

Calorie restriction hysteretically primes aging Saccharomyces cerevisiae toward more effective oxidative metabolism.

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Erich B Tahara

Full Text Available Calorie restriction (CR is an intervention known to extend the lifespan of a wide variety of organisms. In S. cerevisiae, chronological lifespan is prolonged by decreasing glucose availability in the culture media, a model for CR. The mechanism has been proposed to involve an increase in the oxidative (versus fermentative metabolism of glucose. Here, we measured wild-type and respiratory incompetent (ρ(0 S. cerevisiae biomass formation, pH, oxygen and glucose consumption, and the evolution of ethanol, glycerol, acetate, pyruvate and succinate levels during the course of 28 days of chronological aging, aiming to identify metabolic changes responsible for the effects of CR. The concomitant and quantitative measurements allowed for calculations of conversion factors between different pairs of substrates and products, maximum specific substrate consumption and product formation rates and maximum specific growth rates. Interestingly, we found that the limitation of glucose availability in CR S. cerevisiae cultures hysteretically increases oxygen consumption rates many hours after the complete exhaustion of glucose from the media. Surprisingly, glucose-to-ethanol conversion and cellular growth supported by glucose were not quantitatively altered by CR. Instead, we found that CR primed the cells for earlier, faster and more efficient metabolism of respiratory substrates, especially ethanol. Since lifespan-enhancing effects of CR are absent in respiratory incompetent ρ(0 cells, we propose that the hysteretic effect of glucose limitation on oxidative metabolism is central toward chronological lifespan extension by CR in this yeast.

Anti-Saccharomyces cerevisiae autoantibodies in autoimmune diseases: from bread baking to autoimmunity.

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Rinaldi, Maurizio; Perricone, Roberto; Blank, Miri; Perricone, Carlo; Shoenfeld, Yehuda

2013-10-01

Saccharomyces cerevisiae is best known as the baker's and brewer's yeast, but its residual traces are also frequent excipients in some vaccines. Although anti-S. cerevisiae autoantibodies (ASCAs) are considered specific for Crohn's disease, a growing number of studies have detected high levels of ASCAs in patients affected with autoimmune diseases as compared with healthy controls, including antiphospholipid syndrome, systemic lupus erythematosus, type 1 diabetes mellitus, and rheumatoid arthritis. Commensal microorganisms such as Saccharomyces are required for nutrition, proper development of Peyer's aggregated lymphoid tissue, and tissue healing. However, even the commensal nonclassically pathogenic microbiota can trigger autoimmunity when fine regulation of immune tolerance does not work properly. For our purposes, the protein database of the National Center for Biotechnology Information (NCBI) was consulted, comparing Saccharomyces mannan to several molecules with a pathogenetic role in autoimmune diseases. Thanks to the NCBI bioinformation technology tool, several overlaps in molecular structures (50-100 %) were identified when yeast mannan, and the most common autoantigens were compared. The autoantigen U2 snRNP B″ was found to conserve a superfamily protein domain that shares 83 % of the S. cerevisiae mannan sequence. Furthermore, ASCAs may be present years before the diagnosis of some associated autoimmune diseases as they were retrospectively found in the preserved blood samples of soldiers who became affected by Crohn's disease years later. Our results strongly suggest that ASCAs' role in clinical practice should be better addressed in order to evaluate their predictive or prognostic relevance.

The cellular response of Saccharomyces cerevisiae to multi-walled carbon nanotubes (MWCNTs

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Chantelle L. Phillips

2015-03-01

Full Text Available Nanoparticles (NPs especially those of carbon nanotubes (CNTs have remarkable properties that are very desirable in various biological and biomedical applications. This has necessitated the rapid study of CNT toxicities, to augment their safe use, particularly, in yeast cells. The yeast cell; Saccharomyces cerevisiae is a widely used industrial and biological organism with very limited data regarding their cellular behaviour in NPs. The current study examines the cellular response of S. cerevisiae to MWCNTs. The CNTs were produced by the swirled floating catalytic chemical vapour deposition (SFCCVD method and covalently functionalised using 1,3-dipolar cycloaddition. The CNT properties such as size, surface area, quality and surface vibrations were characterized using TEM, SEM, BET, TGA and Raman spectroscopy, respectively. The cellular uptake was confirmed with a FITC functionalised MWCNTs using 1H NMR, SEM and TEM. The CNT concentrations of 2–40 μg/ml were used to determine the cellular response through cell growth phases and cell viability characteristics. The TEM and SEM analyses showed the production of MWCNTs with an average diameter of 53 ± 12 nm and a length of 2.5 ± 0.5 μm. The cellular uptake of FITC-MWCNTs showed 100% internalisation in the yeast cells. The growth curve responses to the MWCNT doses showed no significant differences at P > 0.05 on the growth rate and viability of the S. cerevisiae cells.

DE PASSADOS POSSÍVEIS: REFLEXÕES SOBRE DISCURSO(S E PATRIMÔNIO(S

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Martha Helena Loeblein Becker Morales

2013-02-01

Full Text Available Este artigo procura refletir acerca do passado como categoria discursiva, ancorado na contribuição teórica de Michel Foucault. Por meio de levantamento e discussão bibliográfica que contempla, em especial, os campos da História, da Arqueologia e do Patrimônio, objetiva-se ponderar sobre a construção conceitual em torno do estudo do passado, conforme desenvolvimentos teóricos recentes. Parte inicial de um trabalho mais amplo, este é um texto que convida o leitor a conhecer e situar alguns debates centrais para questões tão atuais quanto problemáticas como a gestão pública do patrimônio cultural. Palavras-chave: passado, discurso, patrimônio   ABSTRACT This article reflects upon the past as a discursive analytical category, based on Michel Foucault’s theoretical contributions. Through a bibliographical survey and analysis regarding especially the fields of History, Archaeology and Heritage, the purpose is to shed light on the conceptual framework construction of the study of the past, considering recent theoretical developments. As part of a bigger project, this is a text that invites its reader to know and to place some of the key debates surrounding issues as current and problematic as the public management of cultural heritage. Key-words: past, discourse, heritage

Biocatalytic production of adipic acid from glucose using engineered Saccharomyces cerevisiae

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Kaushik Raj

2018-06-01

Full Text Available Adipic acid is an important industrial chemical used in the synthesis of nylon-6,6. The commercial synthesis of adipic acid uses petroleum-derived benzene and releases significant quantities of greenhouse gases. Biocatalytic production of adipic acid from renewable feedstocks could potentially reduce the environmental damage and eliminate the need for fossil fuel precursors. Recently, we have demonstrated the first enzymatic hydrogenation of muconic acid to adipic acid using microbial enoate reductases (ERs - complex iron-sulfur and flavin containing enzymes. In this work, we successfully expressed the Bacillus coagulans ER in a Saccharomyces cerevisiae strain producing muconic acid and developed a three-stage fermentation process enabling the synthesis of adipic acid from glucose. The ability to express active ERs and significant acid tolerance of S. cerevisiae highlight the applicability of the developed yeast strain for the biocatalytic production of adipic acid from renewable feedstocks. Keywords: Biosynthesis, Renewable resources, Yeast, Adipic acid, Synthetic biology

Enhanced pathway efficiency of Saccharomyces cerevisiae by introducing thermo-tolerant devices.

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Liu, Yueqin; Zhang, Genli; Sun, Huan; Sun, Xiangying; Jiang, Nisi; Rasool, Aamir; Lin, Zhanglin; Li, Chun

2014-10-01

In this study, thermo-tolerant devices consisting of heat shock genes from thermophiles were designed and introduced into Saccharomyces cerevisiae for improving its thermo-tolerance. Among ten engineered thermo-tolerant yeasts, T.te-TTE2469, T.te-GroS2 and T.te-IbpA displayed over 25% increased cell density and 1.5-4-fold cell viability compared with the control. Physiological characteristics of thermo-tolerant strains revealed that better cell wall integrity, higher trehalose content and enhanced metabolic energy were preserved by thermo-tolerant devices. Engineered thermo-tolerant strain was used to investigate the impact of thermo-tolerant device on pathway efficiency by introducing β-amyrin synthesis pathway, showed 28.1% increased β-amyrin titer, 28-35°C broadened growth temperature range and 72h shortened fermentation period. The results indicated that implanting heat shock proteins from thermophiles to S. cerevisiae would be an efficient approach to improve its thermo-tolerance. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of NADH-preferring xylose reductase expression on ethanol production from xylose in xylose-metabolizing recombinant Saccharomyces cerevisiae.

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Lee, Sung-Haeng; Kodaki, Tsutomu; Park, Yong-Cheol; Seo, Jin-Ho

2012-04-30

Efficient conversion of xylose to ethanol is an essential factor for commercialization of lignocellulosic ethanol. To minimize production of xylitol, a major by-product in xylose metabolism and concomitantly improve ethanol production, Saccharomyces cerevisiae D452-2 was engineered to overexpress NADH-preferable xylose reductase mutant (XR(MUT)) and NAD⁺-dependent xylitol dehydrogenase (XDH) from Pichia stipitis and endogenous xylulokinase (XK). In vitro enzyme assay confirmed the functional expression of XR(MUT), XDH and XK in recombinant S. cerevisiae strains. The change of wild type XR to XR(MUT) along with XK overexpression led to reduction of xylitol accumulation in microaerobic culture. More modulation of the xylose metabolism including overexpression of XR(MUT) and transaldolase, and disruption of the chromosomal ALD6 gene encoding aldehyde dehydrogenase (SX6(MUT)) improved the performance of ethanol production from xylose remarkably. Finally, oxygen-limited fermentation of S. cerevisiae SX6(MUT) resulted in 0.64 g l⁻¹ h⁻¹ xylose consumption rate, 0.25 g l⁻¹ h⁻¹ ethanol productivity and 39% ethanol yield based on the xylose consumed, which were 1.8, 4.2 and 2.2 times higher than the corresponding values of recombinant S. cerevisiae expressing XR(MUT), XDH and XK only. Copyright © 2011 Elsevier B.V. All rights reserved.

Verificação de requisitos de segurança de tratores agrícolas em alguns municípios do estado de São Paulo

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Ila Maria Corrêa

Full Text Available Um levantamento de informações foi realizado com o objetivo de avaliar as condições de segurança de tratores agrícolas novos e usados em alguns municípios do estado de São Paulo. Foram avaliados 487 tratores em uso em 270 propriedades agrícolas do estado de São Paulo e 31 tratores novos disponíveis em revendas e em exposição em feiras agrícolas, sendo inspecionados alguns requisitos de segurança relativos a posto de operação, acesso, comandos, proteção de partes móveis, disponibilização de avisos contra riscos de acidentes e requisitos necessários para tráfego em rodovias, previstos em documentos normativos nacionais e/ou internacionais. Verificou-se que os tratores em uso no campo não favorecem a segurança e o conforto do operador, enquanto que os tratores novos mostram tendência de atendimento aos requisitos de segurança e conforto, principalmente aqueles relacionados ao posto de operação e à proteção de partes ativas.

Breeding of lager yeast with Saccharomyces cerevisiae improves stress resistance and fermentation performance.

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Garcia Sanchez, Rosa; Solodovnikova, Natalia; Wendland, Jürgen

2012-08-01

Lager beer brewing relies on strains collectively known as Saccharomyces carlsbergensis, which are hybrids between S. cerevisiae and S. eubayanus-like strains. Lager yeasts are particularly adapted to low-temperature fermentations. Selection of new yeast strains for improved traits or fermentation performance is laborious, due to the allotetraploid nature of lager yeasts. Initially, we have generated new F1 hybrids by classical genetics, using spore clones of lager yeast and S. cerevisiae and complementation of auxotrophies of the single strains upon mating. These hybrids were improved on several parameters, including growth at elevated temperature and resistance against high osmolarity or high ethanol concentrations. Due to the uncertainty of chromosomal make-up of lager yeast spore clones, we introduced molecular markers to analyse mating-type composition by PCR. Based on these results, new hybrids between a lager and an ale yeast strain were isolated by micromanipulation. These hybrids were not subject to genetic modification. We generated and verified 13 hybrid strains. All of these hybrid strains showed improved stress resistance as seen in the ale parent, including improved survival at the end of fermentation. Importantly, some of the strains showed improved fermentation rates using 18° Plato at 18-25°C. Uniparental mitochondrial DNA inheritance was observed mostly from the S. cerevisiae parent. Copyright © 2012 John Wiley & Sons, Ltd.

Transcriptome response to alkane biofuels in Saccharomyces cerevisiae: identification of efflux pumps involved in alkane tolerance

Science.gov (United States)

2013-01-01

Background Hydrocarbon alkanes have been recently considered as important next-generation biofuels because microbial production of alkane biofuels was demonstrated. However, the toxicity of alkanes to microbial hosts can possibly be a bottleneck for high productivity of alkane biofuels. To tackle this toxicity issue, it is essential to understand molecular mechanisms of interactions between alkanes and microbial hosts, and to harness these mechanisms to develop microbial host strains with improved tolerance against alkanes. In this study, we aimed to improve the tolerance of Saccharomyces cerevisiae, a model eukaryotic host of industrial significance, to alkane biofuels by exploiting cellular mechanisms underlying alkane response. Results To this end, we first confirmed that nonane (C9), decane (C10), and undecane (C11) were significantly toxic and accumulated in S. cerevisiae. Transcriptome analyses suggested that C9 and C10 induced a range of cellular mechanisms such as efflux pumps, membrane modification, radical detoxification, and energy supply. Since efflux pumps could possibly aid in alkane secretion, thereby reducing the cytotoxicity, we formed the hypothesis that those induced efflux pumps could contribute to alkane export and tolerance. In support of this hypothesis, we demonstrated the roles of the efflux pumps Snq2p and Pdr5p in reducing intracellular levels of C10 and C11, as well as enhancing tolerance levels against C10 and C11. This result provided the evidence that Snq2p and Pdr5p were associated with alkane export and tolerance in S. cerevisiae. Conclusions Here, we investigated the cellular mechanisms of S. cerevisiae response to alkane biofuels at a systems level through transcriptome analyses. Based on these mechanisms, we identified efflux pumps involved in alkane export and tolerance in S. cerevisiae. We believe that the results here provide valuable insights into designing microbial engineering strategies to improve cellular tolerance for

Sentimento de gratidão na infância: algumas considerações teóricas

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Rava, Paula Grazziotin Silveira

2014-01-01

O objetivo deste estudo é apresentar uma discussão teórica sobre o tema da gratidão. Inicialmente, define-se como se entende a gratidão neste trabalho. Prossegue-se versando sobre o que se sabe sobre a gratidão na infância. Por último, tem-se uma revisão de alguns resultados de estudos recentes, enfocando especialmente aqueles que versam sobre a distinção entre gratidão e obrigação. A gratidão tem sido estudada pelos psicólogos, mas as pesquisas empíricas enfocando o desenvolvimento desse sen...

Improving L-arabinose utilization of pentose fermenting Saccharomyces cerevisiae cells by heterologous expression of L-arabinose transporting sugar transporters

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Boles Eckhard

2011-10-01

Full Text Available Abstract Background Hydrolysates of plant biomass used for the production of lignocellulosic biofuels typically contain sugar mixtures consisting mainly of D-glucose and D-xylose, and minor amounts of L-arabinose. The yeast Saccharomyces cerevisiae is the preferred microorganism for the fermentative production of ethanol but is not able to ferment pentose sugars. Although D-xylose and L-arabinose fermenting S. cerevisiae strains have been constructed recently, pentose uptake is still a limiting step in mixed sugar fermentations. Results Here we described the cloning and characterization of two sugar transporters, AraT from the yeast Scheffersomyces stipitis and Stp2 from the plant Arabidopsis thaliana, which mediate the uptake of L-arabinose but not of D-glucose into S. cerevisiae cells. A yeast strain lacking all of its endogenous hexose transporter genes and expressing a bacterial L-arabinose utilization pathway could no longer take up and grow with L-arabinose as the only carbon source. Expression of the heterologous transporters supported uptake and utilization of L-arabinose especially at low L-arabinose concentrations but did not, or only very weakly, support D-glucose uptake and utilization. In contrast, the S. cerevisiae D-galactose transporter, Gal2, mediated uptake of both L-arabinose and D-glucose, especially at high concentrations. Conclusions Using a newly developed screening system we have identified two heterologous sugar transporters from a yeast and a plant which can support uptake and utilization of L-arabinose in L-arabinose fermenting S. cerevisiae cells, especially at low L-arabinose concentrations.

Pichia pastoris versus Saccharomyces cerevisiae: a case study on the recombinant production of human granulocyte-macrophage colony-stimulating factor.

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Tran, Anh-Minh; Nguyen, Thanh-Thao; Nguyen, Cong-Thuan; Huynh-Thi, Xuan-Mai; Nguyen, Cao-Tri; Trinh, Minh-Thuong; Tran, Linh-Thuoc; Cartwright, Stephanie P; Bill, Roslyn M; Tran-Van, Hieu

2017-04-04

Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) is a glycoprotein that has been approved by the FDA for the treatment of neutropenia and leukemia in combination with chemotherapies. Recombinant hGM-CSF is produced industrially using the baker's yeast, Saccharomyces cerevisiae, by large-scale fermentation. The methylotrophic yeast, Pichia pastoris, has emerged as an alternative host cell system due to its shorter and less immunogenic glycosylation pattern together with higher cell density growth and higher secreted protein yield than S. cerevisiae. In this study, we compared the pipeline from gene to recombinant protein in these two yeasts. Codon optimization in silico for both yeast species showed no difference in frequent codon usage. However, rhGM-CSF expressed from S. cerevisiae BY4742 showed a significant discrepancy in molecular weight from those of P. pastoris X33. Analysis showed purified rhGM-CSF species with molecular weights ranging from 30 to more than 60 kDa. Fed-batch fermentation over 72 h showed that rhGM-CSF was more highly secreted from P. pastoris than S. cerevisiae (285 and 64 mg total secreted protein/L, respectively). Ion exchange chromatography gave higher purity and recovery than hydrophobic interaction chromatography. Purified rhGM-CSF from P. pastoris was 327 times more potent than rhGM-CSF from S. cerevisiae in terms of proliferative stimulating capacity on the hGM-CSF-dependent cell line, TF-1. Our data support a view that the methylotrophic yeast P. pastoris is an effective recombinant host for heterologous rhGM-CSF production.

Engineering a functional 1-deoxy-D-xylulose 5-phosphate (DXP) pathway in Saccharomyces cerevisiae

Energy Technology Data Exchange (ETDEWEB)

Kirby, James [Univ. of California, Berkeley, CA (United States). California Institute of Quantitative Biosciences (QB3); Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Dietzel, Kevin L. [Amyris, inc., Emeryville, CA (United States); Wichmann, Gale [Amyris, inc., Emeryville, CA (United States); Chan, Rossana [Univ. of California, Berkeley, CA (United States). California Institute of Quantitative Biosciences (QB3); Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Antipov, Eugene [Amyris, inc., Emeryville, CA (United States); Moss, Nathan [Amyris, inc., Emeryville, CA (United States); Baidoo, Edward E. K. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Jackson, Peter [Amyris, inc., Emeryville, CA (United States); Gaucher, Sara P. [Amyris, inc., Emeryville, CA (United States); Gottlieb, Shayin [Amyris, inc., Emeryville, CA (United States); LaBarge, Jeremy [Amyris, inc., Emeryville, CA (United States); Mahatdejkul, Tina [Amyris, inc., Emeryville, CA (United States); Hawkins, Kristy M. [Amyris, inc., Emeryville, CA (United States); Muley, Sheela [Amyris, inc., Emeryville, CA (United States); Newman, Jack D. [Amyris, inc., Emeryville, CA (United States); Liu, Pinghua [Boston Univ., MA (United States). Dept. of Chemistry; Keasling, Jay D. [Univ. of California, Berkeley, CA (United States). California Institute of Quantitative Biosciences (QB3); Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Univ. of California, Berkeley, CA (United States). Depts. of Chemical & Biomolecular Engineering and Bioengineering; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Systems & Engineering Div.; Technical Univ. of Denmark, Hoesholm (Denmark). Novo Nodisk Foundation Center for Biosustainability; Zhao, Lishan [Amyris, inc., Emeryville, CA (United States)

2016-10-27

Isoprenoids are made by all free-living organisms and range from essential metabolites like sterols and quinones to more complex compounds like pinene and rubber. They are used in many commercial applications and much work has gone into engineering microbial hosts for their production. Isoprenoids are produced either from acetyl-CoA via the mevalonate pathway or from pyruvate and glyceraldehyde 3-phosphate via the 1-deoxy-D-xylulose 5-phosphate (DXP) pathway. Saccharomyces cerevisiae exclusively utilizes the mevalonate pathway to synthesize native isoprenoids and in fact the alternative DXP pathway has never been found or successfully reconstructed in the eukaryotic cytosol. There are, however, several advantages to isoprenoid synthesis via the DXP pathway, such as a higher theoretical yield, and it has long been a goal to transplant the pathway into yeast. In this work, we investigate and address barriers to DXP pathway functionality in S. cerevisiae using a combination of synthetic biology, biochemistry and metabolomics. We report, for the first time, functional expression of the DXP pathway in S. cerevisiae. Under low aeration conditions, an engineered strain relying solely on the DXP pathway for isoprenoid biosynthesis achieved an endpoint biomass 80% of that of the same strain using the mevalonate pathway.

Gains and Losses of Transcription Factor Binding Sites in Saccharomyces cerevisiae and Saccharomyces paradoxus.

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Schaefke, Bernhard; Wang, Tzi-Yuan; Wang, Chuen-Yi; Li, Wen-Hsiung

2015-07-27

Gene expression evolution occurs through changes in cis- or trans-regulatory elements or both. Interactions between transcription factors (TFs) and their binding sites (TFBSs) constitute one of the most important points where these two regulatory components intersect. In this study, we investigated the evolution of TFBSs in the promoter regions of different Saccharomyces strains and species. We divided the promoter of a gene into the proximal region and the distal region, which are defined, respectively, as the 200-bp region upstream of the transcription starting site and as the 200-bp region upstream of the proximal region. We found that the predicted TFBSs in the proximal promoter regions tend to be evolutionarily more conserved than those in the distal promoter regions. Additionally, Saccharomyces cerevisiae strains used in the fermentation of alcoholic drinks have experienced more TFBS losses than gains compared with strains from other environments (wild strains, laboratory strains, and clinical strains). We also showed that differences in TFBSs correlate with the cis component of gene expression evolution between species (comparing S. cerevisiae and its sister species Saccharomyces paradoxus) and within species (comparing two closely related S. cerevisiae strains). © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

O mito das Olimpíadas: Hesíodo, Bacon, Hobbes e a infindável luta dos titãs

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Luiz Carlos Santos da Silva

2016-08-01

Full Text Available O presente artigo tem por objetivo apresentar alguns dos aspectos mitológicos que fundamentam a realização das olimpíadas desde a antiguidade grega, particularmente a “corrida de tochas acessas” que atualmente inaugura a abertura dos jogos. Para tanto, buscamos apresentar alguns relatos que narram a realização dos jogos olímpicos como uma espécie memória aos mitos fundadores da cultura grega. Nesse registro, consideramos alguns aspectos das narrativas de Hesíodo sobre o mito de Prometeu, bem como algumas observações de filósofos modernos como Francis Bacon e Thomas Hobbes sobre como essa fábula narra a interpretação de uma condição humana fundada em uma competição análoga à uma interminável luta de titãs. Condição humana essa oriunda da desobediência às vontades dos deuses do Olimpo, cristalizada na expressão de uma cultura da competição que visa não apenas agradar a esses deuses, detentores do poder no Olimpo, mas também igualar certos homens a eles.

Increased ethanol accumulation from glucose via reduction of ATP level in a recombinant strain of Saccharomyces cerevisiae overexpressing alkaline phosphatase.

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Semkiv, Marta V; Dmytruk, Kostyantyn V; Abbas, Charles A; Sibirny, Andriy A

2014-05-15

The production of ethyl alcohol by fermentation represents the largest scale application of Saccharomyces cerevisiae in industrial biotechnology. Increased worldwide demand for fuel bioethanol is anticipated over the next decade and will exceed 200 billion liters from further expansions. Our working hypothesis was that the drop in ATP level in S. cerevisiae cells during alcoholic fermentation should lead to an increase in ethanol production (yield and productivity) with a greater amount of the utilized glucose converted to ethanol. Our approach to achieve this goal is to decrease the intracellular ATP level via increasing the unspecific alkaline phosphatase activity. Intact and truncated versions of the S. cerevisiae PHO8 gene coding for vacuolar or cytosolic forms of alkaline phosphatase were fused with the alcohol dehydrogenase gene (ADH1) promoter. The constructed expression cassettes used for transformation vectors also contained the dominant selective marker kanMX4 and S. cerevisiae δ-sequence to facilitate multicopy integration to the genome. Laboratory and industrial ethanol producing strains BY4742 and AS400 overexpressing vacuolar form of alkaline phosphatase were characterized by a slightly lowered intracellular ATP level and biomass accumulation and by an increase in ethanol productivity (13% and 7%) when compared to the parental strains. The strains expressing truncated cytosolic form of alkaline phosphatase showed a prolonged lag-phase, reduced biomass accumulation and a strong defect in ethanol production. Overexpression of vacuolar alkaline phosphatase leads to an increased ethanol yield in S. cerevisiae.

¹³C-based metabolic flux analysis of Saccharomyces cerevisiae with a reduced Crabtree effect.

Science.gov (United States)

Kajihata, Shuichi; Matsuda, Fumio; Yoshimi, Mika; Hayakawa, Kenshi; Furusawa, Chikara; Kanda, Akihisa; Shimizu, Hiroshi

2015-08-01

Saccharomyces cerevisiae shows a Crabtree effect that produces ethanol in a high glucose concentration even under fully aerobic condition. For efficient production of cake yeast or compressed yeast for baking, ethanol by-production is not desired since glucose limited chemostat or fed-batch cultivations are performed to suppress the Crabtree effect. In this study, the (13)C-based metabolic flux analysis ((13)C-MFA) was performed for the S288C derived S. cerevisiae strain to characterize a metabolic state under the reduced Crabtree effect. S. cerevisiae cells were cultured at a low dilution rate (0.1 h(-1)) under the glucose-limited chemostat condition. The estimated metabolic flux distribution showed that the acetyl-CoA in mitochondria was mainly produced from pyruvate by pyruvate dehydrogenase (PDH) reaction and that the level of the metabolic flux through the pentose phosphate pathway was much higher than that of the Embden-Meyerhof-Parnas pathway, which contributes to high biomass yield at low dilution rate by supplying NADPH required for cell growth. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

L-histidine inhibits biofilm formation and FLO11-associated phenotypes in Saccharomyces cerevisiae flor yeasts.

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Bou Zeidan, Marc; Zara, Giacomo; Viti, Carlo; Decorosi, Francesca; Mannazzu, Ilaria; Budroni, Marilena; Giovannetti, Luciana; Zara, Severino

2014-01-01

Flor yeasts of Saccharomyces cerevisiae have an innate diversity of Flo11p which codes for a highly hydrophobic and anionic cell-wall glycoprotein with a fundamental role in biofilm formation. In this study, 380 nitrogen compounds were administered to three S. cerevisiae flor strains handling Flo11p alleles with different expression levels. S. cerevisiae strain S288c was used as the reference strain as it cannot produce Flo11p. The flor strains generally metabolized amino acids and dipeptides as the sole nitrogen source, although with some exceptions regarding L-histidine and histidine containing dipeptides. L-histidine completely inhibited growth and its effect on viability was inversely related to Flo11p expression. Accordingly, L-histidine did not affect the viability of the Δflo11 and S288c strains. Also, L-histidine dramatically decreased air-liquid biofilm formation and adhesion to polystyrene of the flor yeasts with no effect on the transcription level of the Flo11p gene. Moreover, L-histidine modified the chitin and glycans content on the cell-wall of flor yeasts. These findings reveal a novel biological activity of L-histidine in controlling the multicellular behavior of yeasts [corrected].

Heterologous expression of MlcE in Saccharomyces cerevisiae provides resistance to natural and semi-synthetic statins

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Ana Ley

2015-12-01

Full Text Available Statins are inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase, the key enzyme in cholesterol biosynthesis. Their extensive use in treatment and prevention of cardiovascular diseases placed statins among the best selling drugs. Construction of Saccharomyces cerevisiae cell factory for the production of high concentrations of natural statins will require establishment of a non-destructive self-resistance mechanism to overcome the undesirable growth inhibition effects of statins. To establish active export of statins from yeast, and thereby detoxification, we integrated a putative efflux pump-encoding gene mlcE from the mevastatin-producing Penicillium citrinum into the S. cerevisiae genome. The resulting strain showed increased resistance to both natural statins (mevastatin and lovastatin and semi-synthetic statin (simvastatin when compared to the wild type strain. Expression of RFP-tagged mlcE showed that MlcE is localized to the yeast plasma and vacuolar membranes. We provide a possible engineering strategy for improvement of future yeast based production of natural and semi-synthetic statins. Keywords: Polyketide, Statins, Saccharomyces cerevisiae, Transport, Cell factory, Resistance

Atomic force microscopic study of the influence of physical stresses on Saccharomyces cerevisiae and Schizosaccharomyces pombe.

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Adya, Ashok K; Canetta, Elisabetta; Walker, Graeme M

2006-01-01

Morphological changes in the cell surfaces of the budding yeast Saccharomyces cerevisiae (strain NCYC 1681), and the fission yeast Schizosaccharomyces pombe (strain DVPB 1354), in response to thermal and osmotic stresses, were investigated using an atomic force microscope. With this microscope imaging, together with measurements of culture viability and cell size, it was possible to relate topological changes of the cell surface at nanoscale with cellular stress physiology. As expected, when the yeasts were exposed to thermostress or osmostress, their viability together with the mean cell volume decreased in conjunction with the increase in thermal or osmotic shock. Nevertheless, the viability of cells stressed for up to 1 h remained relatively high. For example, viabilities were >50% and >90% for the thermostressed, and >60% and >70% for the osmostressed S. cerevisiae and Schiz. pombe, respectively. Mean cell volume measurements, and bearing and roughness analyses of atomic force microscope images of stressed yeasts indicate that Schiz. pombe may be more resistant to physical stresses than S. cerevisiae. Overall, this study has highlighted the usefulness of atomic force microscope in studies of yeast stress physiology.

Inhibitor tolerance of a recombinant flocculating industrial Saccharomyces cerevisiae strain during glucose and xylose co-fermentation

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Yun-Cheng Li

Full Text Available ABSTRACT Lignocellulose-derived inhibitors have negative effects on the ethanol fermentation capacity of Saccharomyces cerevisiae. In this study, the effects of eight typical inhibitors, including weak acids, furans, and phenols, on glucose and xylose co-fermentation of the recombinant xylose-fermenting flocculating industrial S. cerevisiae strain NAPX37 were evaluated by batch fermentation. Inhibition on glucose fermentation, not that on xylose fermentation, correlated with delayed cell growth. The weak acids and the phenols showed additive effects. The effect of inhibitors on glucose fermentation was as follows (from strongest to weakest: vanillin > phenol > syringaldehyde > 5-HMF > furfural > levulinic acid > acetic acid > formic acid. The effect of inhibitors on xylose fermentation was as follows (from strongest to weakest: phenol > vanillin > syringaldehyde > furfural > 5-HMF > formic acid > levulinic acid > acetic acid. The NAPX37 strain showed substantial tolerance to typical inhibitors and showed good fermentation characteristics, when a medium with inhibitor cocktail or rape straw hydrolysate was used. This research provides important clues for inhibitors tolerance of recombinant industrial xylose-fermenting S. cerevisiae.

Genetic Approaches to Study Meiosis and Meiosis-Specific Gene Expression in Saccharomyces cerevisiae.

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Kassir, Yona; Stuart, David T

2017-01-01

The budding yeast Saccharomyces cerevisiae has a long history as a model organism for studies of meiosis and the cell cycle. The popularity of this yeast as a model is in large part due to the variety of genetic and cytological approaches that can be effectively performed with the cells. Cultures of the cells can be induced to synchronously progress through meiosis and sporulation allowing large-scale gene expression and biochemical studies to be performed. Additionally, the spore tetrads resulting from meiosis make it possible to characterize the haploid products of meiosis allowing investigation of meiotic recombination and chromosome segregation. Here we describe genetic methods for analysis progression of S. cerevisiae through meiosis and sporulation with an emphasis on strategies for the genetic analysis of regulators of meiosis-specific genes.

Saccharomyces cerevisiae biofilm tolerance towards systemic antifungals depends on growth phase

DEFF Research Database (Denmark)

Bojsen, Rasmus Kenneth; Regenberg, Birgitte; Folkesson, Sven Anders

2014-01-01

Background : Biofilm-forming Candida species cause infections that can be difficult to eradicate, possibly because of antifungal drug tolerance mechanisms specific to biofilms. In spite of decades of research, the connection between biofilm and drug tolerance is not fully understood. Results : We...... used Saccharomyces cerevisiae as a model for drug susceptibility of yeast biofilms. Confocal laser scanning microscopy showed that S. cerevisiae and C. glabrata form similarly structured biofilms and that the viable cell numbers were significantly reduced by treatment of mature biofilms...... with amphotericin B but not voriconazole, flucytosine, or caspofungin. We showed that metabolic activity in yeast biofilm cells decreased with time, as visualized by FUN-1 staining, and mature, 48-hour biofilms contained cells with slow metabolism and limited growth. Time-kill studies showed that in exponentially...

Prácticas de sí e contra-conducta de usuarios de marihuana: elementos para pensar una educación sobre drogas

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Tiago Magalhães Ribeiro

2014-02-01

Full Text Available O artigo apresenta uma reflexão acerca dos modos pelos quais usuários de maconha têm desenvolvido coletivamente novas formas de subjetividade. Tais modos entendem-se como um processo de produção de uma contraconduta, que é descrito e problematizado no sentido de se pensarem alguns elementos para propor uma educação sobre drogas. A partir de ferramentas foucaultiana ?como as noções de “ética”, “práticas de si” e “contraconduta”? e de material empírico coletado em um fórum da internet, trata-se de um mapeamento dos modos pelos quais usuários de maconha vêm elaborando formas de relação consigo mesmos que recusam a sua identificação como criminosos e/ou doentes e buscam a integração na ordem política e social a partir da constituição de si como sujeitos trabalhadores e responsáveis.

Estudio comparativo entre aislados clínicos y no clínicos de S. cerevisiae y su papel como patógeno emergente.

OpenAIRE

Llanos Frutos, Rosa de

2007-01-01

RESUMEN La levadura Saccharomyces cerevisiae es la especie más utilizada desde un punto de vista biotecnológico. En la industria agroalimentaria interviene en la elaboración de pan y bebidas alcohólicas como el vino y la cerveza, además se emplea como suplemento dietético y como agente probiótico bajo el nombre de S. cerevisiae var. boulardii. A pesar de sus propiedades beneficiosas, S. cerevisiae se considera actualmente una levadura patógena oportunista emergente de baja virulencia, capa...

Engineering of Saccharomyces cerevisiae for Efficient Anaerobic Alcoholic Fermentation of L-Arabinose

NARCIS (Netherlands)

Wisselink, H.W.; Toirkens, M.J.; Del Rosario Franco Berriel, M.; Winkler, A.A.; Van Dijken, J.P.; Pronk, J.T.; Van Maris, A.J.A.

2007-01-01

For cost-effective and efficient ethanol production from lignocellulosic fractions of plant biomass, the conversion of not only major constituents, such as glucose and xylose, but also less predominant sugars, such as L-arabinose, is required. Wild-type strains of Saccharomyces cerevisiae, the

Prokaryotic diversity of the Saccharomyces cerevisiae Atx1p-mediated copper pathway.

NARCIS (Netherlands)

Bakel, H. van; Huynen, M.A.; Wijmenga, C.

2004-01-01

MOTIVATION: Several genes involved in the cellular import of copper and its subsequent incorporation into the high-affinity iron transport complex in Saccharomyces cerevisiae are known to be conserved between eukaryotes and prokaryotes. However, the degree to which these genes share their functional

Blog literário: alguns comentários

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Alamir Aquino Corrêa

2015-07-01

Full Text Available http://dx.doi.org/10.5007/1807-9288.2015v11n1p420 Se o conceito de literatura é marcado por discussões e reformulações ao longo da história, parece-nos importante partir da ideia que “as escritas de si” presentes na pós-modernidade apontam para a revisão de algumas noções a respeito do ficcional e da literariedade presentes em textos que são veiculados na internet, especificamente o blog. A escrita de autoria feminina, tradicional espaço de expressão subjetiva recolhida muitas vezes apenas em diários íntimos, encontrou na internet um meio para fazer ecoar vozes antes silenciadas devido à condição da mulher na sociedade e, portanto, também terá destaque dentre os assuntos aqui discutidos, ao lado de reflexões sobre a canonicidade de textos e da configuração do blog como espaço de autorreferencialidade e de publicidade da escrita literária.

Immobilized Saccharomyces cerevisiae as a potential aflatoxin decontaminating agent in pistachio nuts

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S. Rahaie

2010-03-01

Full Text Available In this study, we investigated the binding ability of Saccharomayces cerevisiae to aflatoxin in pistachio nuts. The obtained results indicate that S. cerevisiae has an aflatoxin surface binding ability of 40% and 70% (with initial aflatoxin concentrations of 10 and 20 ppb in the exponential phase. Acid treatments increase this ability to approximately 60% and 73% for the two concentrations of aflatoxin, respectively. Heat treatments also enhance surface binding to 55% and 75%, respectively. Binding appears to be a physical phenomenon that saturates within the first 2-3 hours of the process. The obtained results indicate that yeast immobilization for toxin reduction on aflatoxin-contaminated pistachios had no effect on qualitative characteristics, such as color, texture, and peroxide value. Yeast cells, viable or nonviable, are effective for aflatoxin binding, and this property could lead to a promising solution to aflatoxin contamination in high-risk foods.

Reflexões sobre adaptação cinematográfica de uma obra literária

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Thais Maria Gonçalves da Silva

2012-11-01

Full Text Available O cinema e a literatura mantém uma relação quase tão antiga quanto o próprio cinema. Quando a 7º arte percebeu todo seu potencial narrativo, procurou se apoiar em um modo já consagrado de contar história, a literatura. Por outro lado, a literatura ao se deparar com essa nova arte do movimento, não apenas incorporou muito dela em si mesma, como também percebeu que finalmente poderia se libertar a tarefa de narrar, pois o cinema ocupava agora esse lugar, e se aventurar no campo da experimentação. Este artigo tem como objetivo, mediante as ideias de alguns críticos – desde Jean Epstein, em 1921 até Arlindo Machado, em 2007 –, colocar o leitor diante da questão de literatura e cinema através do tempo, vendo como essas duas artes se embatem e se influenciam e lançar certa luz sobre o problema de adaptação da obra literária para uma obra cinematográfica, assunto que despertar grande interessa ao estudioso de literatura, uma vez que é grande o número de filmes que usam um texto literário como fonte.

Sobre a condenação do magnetismo animal: revisitando a história da psicologia

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Maurício da Silva Neubern

Full Text Available O presente trabalho procura desenvolver uma reflexão crítica sobre o processo de condenação do magnetismo animal. Partindo de uma crítica às versões lineares e progressistas da história da Psicologia, nas quais o magnetismo é excluído ou pouco explorado, o artigo busca atingir dois objetivos. Primeiramente, questionar alguns dos pressupostos típicos das versões históricas dominantes, como a idéia de que o magnetismo não teria resistido às exigências da metodologia científica. Em segundo lugar, oferecer uma alternativa de compreensão deste processo calcada na idéia de que a rejeição ao magnetismo animal ocorreu, em parte, devido à oposição de princípios epistemológicos existente entre este e o projeto moderno de ciência. O artigo é concluído destacando o caráter acidental do nascimento do espaço psicológico a partir desta condenação, a diversidade de razões nela presentes e questiona a noção de progresso típico ao projeto moderno de ciência que inspirou o nascimento da Psicologia.

PATRONES DE TURING SOBRE ESFERAS CON CRECIMIENTO CONTINUO PADRÕES DE TURING SOBRE ESFERAS COM CRESCIMENTO CONTÍNUO TURING PATTERNS ON SPHERES WITH CONTINUOUS GROWTH

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Diego A. Garzón

2012-06-01

Full Text Available En este artículo se desarrollan varios ejemplos numéricos sobre ecuaciones de reacción-difusión con dominio creciente, empleando el modelo de reacción de Schnakenberg, con parámetros en el espacio de Turing. Por tanto, se realizan ensayos numéricos sobre la aparición de los patrones de Turing en superficies esféricas. Para la solución de las ecuaciones de reacción-difusión se presenta un método de solución en superficies en tres dimensiones mediante el método de los elementos finitos con el uso de la formulación lagrangiana total. Los resultados muestran que la formación de los patrones de Turing depende de la velocidad de crecimiento de la superficie, el tipo de número de onda predicho en la teoría de dominios cuadrados y su tiempo de estabilización. Estos resultados pueden esclarecer algunos fenómenos de cambio de patrón en la superficie de la piel de los animales que exhiben manchas características.Neste artigo desenvolvem-se vários exemplos numéricos sobre equações de reação-difusão com domínio crescente, empregando o modelo de reação de Schnakenberg, com parâmetros no espaço de Turing. Por tanto, realizam-se ensaios numéricos sobre o aparecimento dos padrões de Turing em superfícies esféricas. Para a solução das equações de reação-difusão apresenta-se um método de solução em superfícies em três dimensões mediante o método dos elementos finitos baixo o uso da formulação lagrangiana total. Os resultados mostram que a formação dos padrões de Turing depende da velocidade de crescimento da superfície, o tipo de número de onda predito na teoria de domínios quadrados e seu tempo de estabilização. Estes resultados podem esclarecer alguns fenômenos de mudança de padrão na superfície da pele dos animais que exibem manchas características.We have developed several numerical examples of reaction-diffusion equations with growth surface domain. In this research we use the Schnakenberg