How different anthropogenic environments have shaped the genome of S. cerevisiae ?

The yeast Saccharomyces cerevisiae plays an important role in food and beverage fermentations. In order to known how environmental constraints imposed by anthropogenic niches have shaped S. cerevisiae genomes and phenotypes, we sequenced the genome of 82 S. cerevisiae strains from various ecological origins. Using these genomic data, we found additional genetic elements acquired by introgression or by horizontal transfer. Here, we present two remarkable examples of divergent adaptation associated to yeast domestication for wine and milk fermentation. Firstly, we demonstrated the role of oligopeptide transporters encoded by FOT genes, which are recently acquired by wine yeasts from Torulaspora microellipsoides. These transporters with a broader specificity than S. cerevisiae dipeptides transporters, confer a strong competitive advantage during grape must fermentation and thus play a key role in the adaptation of wine yeasts to the nitrogen-limited wine fermentation environment. The genome of cheese strains, secondly, present some particular features. Genes of the GAL locus were replaced by their orthologues from a species apparently basal to the Saccharomyces clade. Allelic exchange of this locus in a wine strain enables improves growth speed in a media containing the two hexoses such as when released from the hydrolysis of lactose. In addition, a highly divergent high affinity transporter GAL2 and a specific allele of the regulator GAL80 were found. This work highlights the remarkable plasticity of yeast genomes as a mechanism of their adaptation to their environment

Evolutionary Advantage Conferred by an Eukaryote-to-Eukaryote Gene Transfer Event in Wine Yeasts

Although an increasing number of horizontal gene transfers have been reported in eukaryotes, experimental evidence for their adaptive value is lacking. Here, we report the recent transfer of a 158-kb genomic region between Torulaspora microellipsoides and Saccharomyces cerevisiae wine yeasts or closely related strains. This genomic region has undergone several rearrangements in S. cerevisiae strains, including gene loss and gene conversion between two tandemly duplicated FOT genes encoding oligopeptide transporters. We show that FOT genes confer a strong competitive advantage during grape must fermentation by increasing the number and diversity of oligopeptides that yeast can utilize as a source of nitrogen, thereby improving biomass formation, fermentation efficiency, and cell viability. Thus, the acquisition of FOT genes has favored yeast adaptation to the nitrogen-limited wine fermentation environment. This finding indicates that anthropic environments offer substantial ecological opportunity for evolutionary diversification through gene exchange between distant yeast species

A influência do teatro no turismo em Curitiba

Orientador : Sandro Campos NevesMonografia (graduação) - Universidade Federal do Paraná, Setor de Ciências Humanas, Curso de Graduação em TurismoInclui referênciasResumo : O presente trabalho analisou o atual cenário de teatro em Curitiba e a influência exercida pelo Festival de Teatro de Curitiba no turismo da cidade. Para cumprir com o objetivo central, realizou-se pesquisa exploratória e bibliográfica, que fundamentaram o referencial teórico, dividido nos seguintes tópicos: turismo e cultura; eventos e turismo; teatro e festivais; festival de teatro de Curitiba; Espaço Positivo. Em seguida, foi aplicada a técnica de estudo de caso para o público presente na 27° edição do Festival, sendo a coleta de dados realizada por meio de questionários previamente estruturados, além de um roteiro de entrevista aplicado a gestora do Teatro Positivo, para compreender melhor a oferta da cidade. A análise dos dados coletados foi realizada por análise de conteúdo, onde as informações foram apresentadas através de gráficos e quadros, que auxiliaram na interpretação dos dados. As informações obtidas possibilitaram uma melhor interpretação da cena teatral de Curitiba, com foco no Festival de Teatro de Curitiba e no Teatro Positivo, objetos de estudo desse trabalho. Foi possível identificar que o teatro como influência para atrair a visita de turistas não é satisfatória, sendo a maior parte do público presente de Curitiba e região. Em resposta, propôs-se um projeto que utiliza uma estratégia de marketing online, através de mídias sociais, que consiste na elaboração de postagens em plataformas acessadas pelo público alvo do evento, com o objetivo de melhorar a divulgação, trazendo um número maior de visitantes.Abstract : The present paper analyzed the current theater scene in Curitiba and the influence exerted by the Festival de Teatro de Curitiba in the city tourism. In order to fulfill the central objective, an exploratory and bibliographical research was carried out, which based the theoretical reference, divided in the following topics: tourism and culture; events and tourism; theater and festivals; Festival de Teatro de Curitiba; Espaço Positivo. Then, the case study technique was applied to the audience present at the 27th Festival de Teatro de Curitiba, and the data collection was carried out through previously structured questionnaires, as well as an interview script applied to the Teatro Positivo manager, to understand better the offer of the city. The analysis of the collected data was performed by content analysis, where the information was presented through graphs and tables, which helped in the interpretation of the data. The information obtained allowed a better interpretation of the theatrical scene of Curitiba, focusing on the Festival de Teatro de Curitiba and Teatro Positivo, objects of study of this paper. It was possible to identify that the theater as an influence to attract the visit of tourists is not satisfactory, being the majority of the present public of Curitiba and region. In response, a project was proposed that uses an online marketing strategy, through social media, which consists in the elaboration of postings on platforms accessed by the target audience of the event, with the aim of improving the publicity, bringing a greater number of visitors

Amplification of a Zygosaccharomyces bailii DNA Segment in Wine Yeast Genomes by Extrachromosomal Circular DNA Formation

We recently described the presence of large chromosomal segments resulting from independent horizontal gene transfer (HGT) events in the genome of Saccharomyces cerevisiae strains, mostly of wine origin. We report here evidence for the amplification of one of these segments, a 17 kb DNA segment from Zygosaccharomyces bailii, in the genome of S. cerevisiae strains. The copy number, organization and location of this region differ considerably between strains, indicating that the insertions are independent and that they are post-HGT events. We identified eight different forms in 28 S. cerevisiae strains, mostly of wine origin, with up to four different copies in a single strain. The organization of these forms and the identification of an autonomously replicating sequence functional in S. cerevisiae, strongly suggest that an extrachromosomal circular DNA (eccDNA) molecule serves as an intermediate in the amplification of the Z. bailii region in yeast genomes. We found little or no sequence similarity at the breakpoint regions, suggesting that the insertions may be mediated by nonhomologous recombination. The diversity between these regions in S. cerevisiae represents roughly one third the divergence among the genomes of wine strains, which confirms the recent origin of this event, posterior to the start of wine strain expansion. This is the first report of a circle-based mechanism for the expansion of a DNA segment, mediated by nonhomologous recombination, in natural yeast populations

Evaluating the strain effect in a model consortium of the wine yeast community

International audienceIn recent years, many synthetic communities have been designed to help understanding ecological drivers of microbial interactions. Fermented food microbial communities, such as the wine yeast community, offer a great opportunity to develop model consortia due to their reduced initial diversity compared to other environmental microbial communities. While the species included in such consortia are generally well discussed, little attention has been paid to the strain choice when constructing synthetic consortia. Here, we sought to investigate the effect of yeast strains on the fermentation of nine randomly generated consortia. Each consortium was composed of the same set of seven species representing the most commonly isolated from winemaking environments (Saccharomyces cerevisiae, Hanseniaspora uvarum, Metschnikowia pulcherrima, Pichia kudriavzevii, Starmerella bacillaris, Lachancea thermotolerans, and Torulaspora delbrueckii) but with different strain compositions (3 strains per non-Saccharomyces species). To compare the performance of the nine consortia, we assessed the fermentation kinetics, the population dynamics and the final concentrations of central carbon metabolites. Despite the initial intraspecific phenotype variability of the strains, our results suggest that strains had limited impact on the fermentation kinetics and invasion by S. cerevisiae when included in consortia. Indeed, we observed very few specific associations between a specific strain and variations of phenotypic traits in consortia. Our findings will be of great interest for microbial ecology research and conception of optimized microbial consortia

The Saccharomyces cerevisiae zinc factor protein Stb5p is required as a basal regulator of the pentose phosphate pathway

Correspondance auteur: Dequin S. E-mail: [email protected] audienceIn Saccharomyces cerevisiae, the oxidative stress-activated zinc cluster protein Stb5p activates genes involved in NADPH production and most genes of the pentose phosphate (PP) pathway. To gain insight into the role of Stb5p, we studied the behaviour of stb5 deletion mutants during aerobic and anaerobic growth on glucose. stb5 mutants were auxotrophic for methionine and pyrimidine nucleotides. The methionine auxotrophy phenotype was air dependent, suggesting an impaired aerobic NADPH status. Consistent with this, the acetate level was reduced and the alpha-ketoglutarate level was increased in the stb5 mutant. stb5 cells also required pyrimidine nucleotides for aerobic and anaerobic growth, consistent with a reduction in 5-phosphoribosyl-1-pyrophosphate production caused by a reduced flux through the PP pathway. Strains overexpressing STB5 could not grow on glucose. This growth defect was restored by overproduction of an NADPH-butanediol dehydrogenase, which reoxidizes the excess NADPH in the oxidative PP pathway. These findings suggest a major role for the transcription factor Stb5p in maintaining a basal flux through the PP pathway to meet the NADPH requirements for aerobic growth, and to provide the nucleotide precursors. Our data also demonstrate the potential use of a system based on overproduction of this transcription factor to increase flux through the PP pathwa

Horizontally acquired oligopeptide transporters favor adaptation of Saccharomyces cerevisiae wine yeast to enological environment

In the past decade, horizontal gene transfer (HGT) has emerged as a major evolutionary process that has shaped the genome of Saccharomyces cerevisiae wine yeasts. We recently showed that a large Torulaspora microelliposides genomic island carrying two oligopeptide transporters encoded by FOT genes increases the fitness of wine yeast during fermentation of grape must. However, the impact of these genes on the metabolic network of S. cerevisiae remained uncharacterized. Here we show that Fot-mediated peptide uptake substantially affects the glutamate node and the NADPH/NADP+ balance, resulting in the delayed uptake of free amino acids and altered profiles of metabolites and volatile compounds. Transcriptome analysis revealed that cells using a higher amount of oligopeptides from grape must are less stressed and display substantial variation in the expression of genes in the central pathways of carbon and nitrogen metabolism, amino acid and protein biosynthesis and the oxidative stress response. These regulations shed light on the molecular and metabolic mechanisms involved in the higher performance and fitness conferred by the HGT-acquired FOT genes, pinpointing metabolic effects that can positively affect the organoleptic balance of wines

Souches de levures recombinantes appliquées au contrôle de l'acidité en oenologie

National audienc

Diversity of oligopeptide transporters in industrial yeasts

Diversity of oligopeptide transporters in industrial yeasts. 7. Conference on Physiology of Yeast and Filamentous Fung