44 research outputs found

    Fermentation innovation through complex hybridization of wild and domesticated yeasts

    Get PDF
    The most common fermented beverage, lager beer, is produced by interspecies hybrids of the brewing yeast Saccharomyces cerevisiae and its wild relative S. eubayanus. Lager-brewing yeasts are not the only example of hybrid vigour or heterosis in yeasts, but the full breadth of interspecies hybrids associated with human fermentations has received less attention. Here we present a comprehensive genomic analysis of 122 Saccharomyces hybrids and introgressed strains. These strains arose from hybridization events between two to four species. Hybrids with S. cerevisiae contributions originated from three lineages of domesticated S. cerevisiae, including the major wine-making lineage and two distinct brewing lineages. In contrast, the undomesticated parents of these interspecies hybrids were all from wild Holarctic or European lineages. Most hybrids have inherited a mitochondrial genome from a parent other than S. cerevisiae, which recent functional studies suggest could confer adaptation to colder temperatures. A subset of hybrids associated with crisp flavour profiles, including both lineages of lager-brewing yeasts, have inherited inactivated S. cerevisiae alleles of critical phenolic off-flavour genes and/or lost functional copies from the wild parent through multiple genetic mechanisms. These complex hybrids shed light on the convergent and divergent evolutionary trajectories of interspecies hybrids and their impact on innovation in lager brewing and other diverse fermentation industries.Fil: Langdon, Quinn K.. University of Wisconsin; Estados UnidosFil: Peris, David. University of Wisconsin; Estados Unidos. Consejo Superior de Investigaciones Científicas; EspañaFil: Baker, Emily Clare. University of Wisconsin; Estados UnidosFil: Opulente, Dana A.. University of Wisconsin; Estados UnidosFil: Nguyen, Huu-Vang. Université Paris-Saclay; Francia. Institut National de la Recherche Agronomique; FranciaFil: Bond, Ursula. Trinity College; Estados UnidosFil: Gonçalves, Paula. Universidade Nova de Lisboa; PortugalFil: Sampaio, José Paulo. Universidade Nova de Lisboa; PortugalFil: Libkind Frati, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales. Universidad Nacional del Comahue. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales; ArgentinaFil: Hittinger, Chris. University of Wisconsin; Estados Unido

    Postglacial migration shaped the genomic diversity and global distribution of the wild ancestor of lager-brewing hybrids

    Get PDF
    The wild, cold-adapted parent of hybrid lager-brewing yeasts, Saccharomyces eubayanus, has a complex and understudied natural history. The exploration of this diversity can be used both to develop new brewing applications and to enlighten our understanding of the dynamics of yeast evolution in the wild. Here, we integrate whole genome sequence and phenotypic data of 200 S. eubayanus strains, the largest collection known to date. S. eubayanus has a multilayered population structure, consisting of two major populations that are further structured into six subpopulations. Four of these subpopulations are found exclusively in the Patagonian region of South America; one is found predominantly in Patagonia and sparsely in Oceania and North America; and one is specific to the Holarctic ecozone. Plant host associations differed between subpopulations and between S. eubayanus and its sister species, Saccharomyces uvarum. S. eubayanus is most abundant and genetically diverse in northern Patagonia, where some locations harbor more genetic diversity than is found outside of South America, suggesting that northern Patagonia east of the Andes was a glacial refugium for this species. All but one subpopulation shows isolation-by-distance, and gene flow between subpopulations is low. However, there are strong signals of ancient and recent outcrossing, including two admixed lineages, one that is sympatric with and one that is mostly isolated from its parental populations. Using our extensive biogeographical data, we build a robust model that predicts all known and a handful of additional regions of the globe that are climatically suitable for S. eubayanus, including Europe where host accessibility and competitive exclusion by other Saccharomyces species may explain its continued elusiveness. We conclude that this industrially relevant species has rich natural diversity with many factors contributing to its complex distribution and natural history.Fil: Langdon, Quinn K.. University of Wisconsin; Estados UnidosFil: Peris, David. University of Wisconsin; Estados Unidos. Consejo Superior de Investigaciones Científicas. Instituto de Agroquímica y Tecnología de Alimentos; EspañaFil: Eizaguirre, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales. Universidad Nacional del Comahue. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales; ArgentinaFil: Opulente, Dana A.. University of Wisconsin; Estados UnidosFil: Buh, Kelly V.. University of Wisconsin; Estados UnidosFil: Sylvester, Kayla. University of Wisconsin; Estados UnidosFil: Jarzyna, Martin. University of Wisconsin; Estados UnidosFil: Rodríguez, María Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; ArgentinaFil: Lopes, Christian Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; ArgentinaFil: Libkind Frati, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales. Universidad Nacional del Comahue. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales; ArgentinaFil: Hittinger, Chris. University of Wisconsin; Estados Unido

    Endocrine therapy in epithelial ovarian cancer

    Get PDF
    INTRODUCTION: The estrogen receptor (ER) is expressed at high levels in many epithelial ovarian cancers (EOC) and represents a potential target for endocrine therapy. Both anti-estrogens and aromatase inhibitors have been evaluated in phase II clinical trials. Areas covered: We present an overview of the phase II and phase III trials of anti-estrogens (tamoxifen and fulvestrant) and aromatase inhibitors (letrozole, anastrazole and exemestane) undertaken in epithelial ovarian cancer identified through a Pubmed search. We describe predictive biomarkers that are being investigated to identify responsive cancers. Expert commentary: The efficacy of endocrine therapy in epithelial ovarian cancer is likely to be confined to histological subtypes with the highest ER expression while low grade serous ovarian cancer appears to be one subgroup with good sensitivity to these agents. The low toxicity profile of these agents is favourable although their use is unlicensed and the optimal setting undefined. Prospective clinical trials of endocrine agents in the early relapse and maintenance settings are urgently required to establish their definitive role in the management of epithelial ovarian cancer

    Genome-wide analysis of allelic imbalance in prostate cancer using the Affymetrix 50K SNP mapping array

    Get PDF
    Prostate cancer (PCa) is the most commonly diagnosed non-cutaneous cancer in male subjects in Western countries. The widespread use of prostate-specific antigen (PSA) has increased the detection of this cancer form in earlier stages. Moreover, it has increased the need for new diagnostic procedures to be developed for patient stratification based on risk of progression. We analysed laser-microdissected prostate tumour tissue from 43 patients with histologically verified PCa, using the new high-resolution Affymetrix Mapping 50K single-nucleotide polymorphism array. The results showed six major loss of heterozygosity regions at chromosomes 6q14–16, 8p23–11, 10q23, 13q13–21 and 16q21–24 and a novel region at chromosome 21q22.2, all of which reveal concomitant copy number loss. Tumour development was further characterised by numerous novel genomic regions almost exclusively showing copy number loss. However, tumour progression towards a metastatic stage, as well as poor differentiation, was identified by specific patterns of copy number gains of genomic regions located at chromosomes 8q, 1q, 3q and 7q. Androgen ablation therapy was further characterised by copy gain at chromosomes 2p and 10q. In conclusion, patterns of allelic imbalance were discovered in PCa, consisting allelic loss as an early event in tumour development, and distinct patterns of allelic amplification related to tumour progression and poor differentiation

    Expression of glycolytic enzymes in ovarian cancers and evaluation of the glycolytic pathway as a strategy for ovarian cancer treatment

    Get PDF
    Table S2. Spearman correlation of the expression of four glycolytic enzymes in a cohort of 380 ovarian cancers. Spearman rho correlation values (top value) along with the respective adjusted P value (bottom value) of statistically significant correlations thresholded at FDR P < 0.01 are summarised. (DOCX 21 kb

    Macroevolutionary diversity of traits and genomes in the model yeast genus Saccharomyces

    Get PDF
    Species is the fundamental unit to quantify biodiversity. In recent years, the model yeast Saccharomyces cerevisiae has seen an increased number of studies related to its geographical distribution, population structure, and phenotypic diversity. However, seven additional species from the same genus have been less thoroughly studied, which has limited our understanding of the macroevolutionary events leading to the diversification of this genus over the last 20 million years. Here, we show the geographies, hosts, substrates, and phylogenetic relationships for approximately 1,800 Saccharomyces strains, covering the complete genus with unprecedented breadth and depth. We generated and analyzed complete genome sequences of 163 strains and phenotyped 128 phylogenetically diverse strains. This dataset provides insights about genetic and phenotypic diversity within and between species and populations, quantifies reticulation and incomplete lineage sorting, and demonstrates how gene flow and selection have affected traits, such as galactose metabolism. These findings elevate the genus Saccharomyces as a model to understand biodiversity and evolution in microbial eukaryotes.Some computations were performed on Tirant III of the Spanish Supercomputing Network (“Servei d’Informàtica de la Universitat de València”) under the project BCV-2021-1-0001 granted to DP, while others were performed at the Wisconsin Energy Institute and the Center for High-Throughput Computing of the University of Wisconsin–Madison. During a portion of this project, DP was a researcher funded by the European Union’s Horizon 2020 research and innovation program Marie Sklodowska-Curie, grant agreement No. 747775, the Research Council of Norway (RCN) grant Nos. RCN 324253 and 274337, and the Generalitat Valenciana plan GenT grant No. CIDEGENT/2021/039. D.P. is a recipient of an Illumina Grant for Illumina Sequencing Saccharomyces strains in this study. Q.K.L. was supported by the National Science Foundation under Grant No. DGE-1256259 (Graduate Research Fellowship) and the Predoctoral Training Program in Genetics, funded by the National Institutes of Health (5T32GM007133). This material is based upon work supported in part by the Great Lakes Bioenergy Research Center, Office of Science, Office of Biological and Environmental Research under Award Numbers DE-SC0018409 and DE-FC02-07ER64494; the National Science Foundation under Grant Nos. DEB-1253634, DEB−1442148, and DEB-2110403; and the USDA National Institute of Food and Agriculture Hatch Project Number 1020204. C.T.H. is an H. I. Romnes Faculty Fellow, supported by the Office of the Vice Chancellor for Research and Graduate Education with funding from the Wisconsin Alumni Research Foundation. QMW was supported by the National Natural Science Foundation of China (NSFC) under Grant Nos. 31770018 and 31961133020. C.R.L. holds the Canada Research Chair in Cellular Systems and Synthetic Biology, and his research on wild yeast is supported by an NSERC Discovery Grant.Peer reviewe

    Hybridization and adaptive evolution of diverse Saccharomyces species for cellulosic biofuel production

    Get PDF
    Additional file 15. Summary of whole genome sequencing statistics

    Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

    Get PDF

    Lawson criterion for ignition exceeded in an inertial fusion experiment

    Get PDF
    For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion
    corecore