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Yeager R, Heasley L, Baker N, Shrivastava V, Woodman J, McMurray M. Wild yeast isolation by middle school students reveals features of North American oak populations of Saccharomyces cerevisiae and Kluyveromyces lactis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.27.601111. [PMID: 39005424 PMCID: PMC11244913 DOI: 10.1101/2024.06.27.601111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Features of the natural life cycle of the budding yeast Saccharomyces cerevisiae were crucial to its domestication as a laboratory experimental model, especially the ability to maintain stable haploid clones and cross them at will to combine alleles via meiosis. Stable haploidy results from mutations in HO, which encodes an endonuclease required for haploid-specific mating-type switching. Previous studies found an unexpected diversity of HO alleles among natural isolates within a small geographic area. We developed a hands-on field and laboratory activity for middle school students in Denver, Colorado, USA to isolate wild yeast from oak bark, identify species via DNA sequencing, and sequence HO from S. cerevisiae isolates. We find limited HO diversity in North American oak isolates, pointing to efficient, continuous dispersal across the continent. By contrast, we isolated the "dairy yeast", Kluyveromyces lactis, from a tree <10 m away and found that it represents a new population distinct from an oak population in an adjacent state, pointing to high genetic diversity. The outreach activity partnered middle school, high school, and university students in making scientific discoveries and can be adapted to other locations and natural yeast habitats. Indeed, a pilot sampling activity in southeast Texas yielded S. cerevisiae oak isolates with a new allele of HO and, from a nearby prickly pear cactus, a heat-tolerant isolate of Saccharomyces paradoxus.
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Affiliation(s)
- Randi Yeager
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Lydia Heasley
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Nolan Baker
- CU Science Discovery STEM Research Experience, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Vatsal Shrivastava
- CU Science Discovery STEM Research Experience, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Julie Woodman
- Department of Biology, Colorado Christian University, Lakewood, Colorado, USA
| | - Michael McMurray
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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2
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Atter A, Diaz M, Tano-Debrah K, Parry-Hanson Kunadu A, Mayer MJ, Sayavedra L, Misita C, Amoa-Awua W, Narbad A. The predominant lactic acid bacteria and yeasts involved in the spontaneous fermentation of millet during the production of the traditional porridge Hausa koko in Ghana. BMC Microbiol 2024; 24:163. [PMID: 38745280 PMCID: PMC11092135 DOI: 10.1186/s12866-024-03317-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 05/03/2024] [Indexed: 05/16/2024] Open
Abstract
Spontaneous fermentation of cereals like millet involves a diverse population of microbes from various sources, including raw materials, processing equipment, fermenting receptacles, and the environment. Here, we present data on the predominant microbial species and their succession at each stage of the Hausa koko production process from five regions of Ghana. The isolates were enumerated using selective media, purified, and phenotypically characterised. The LAB isolates were further characterised by 16S rRNA Sanger sequencing, typed using (GTG)5 repetitive-PCR, and whole genome sequencing, while 28S rRNA Sanger sequencing was performed for yeast identification. The pH of the millet grains ranged from mean values of 6.02-6.53 to 3.51-3.99 in the final product, depending on the processors. The mean LAB and yeast counts increased during fermentation then fell to final counts of log 2.77-3.95 CFU/g for LAB and log 2.10-2.98 CFU/g for yeast in Hausa koko samples. At the various processing stages, the counts of LAB and yeast revealed significant variations (p < 0.0001). The species of LAB identified in this study were Limosilactobacillus pontis, Pediococcus acidilactici, Limosilactobacillus fermentum, Limosilactobacillus reuteri, Pediococcus pentosaceus, Lacticaseibacillus paracasei, Lactiplantibacillus plantarum, Schleiferilactobacillus harbinensis, and Weissella confusa. The yeasts were Saccharomyces cf. cerevisiae/paradoxus, Saccharomyces cerevisiae, Pichia kudriavzevii, Clavispora lusitaniae and Candida tropicalis. The identification and sequencing of these novel isolates and how they change during the fermentation process will pave the way for future controlled fermentation, safer starter cultures, and identifying optimal stages for starter culture addition or nutritional interventions. These LAB and yeast species are linked to many indigenous African fermented foods, potentially acting as probiotics in some cases. This result serves as the basis for further studies into the technological and probiotic potential of these Hausa koko microorganisms.
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Affiliation(s)
- Amy Atter
- Food Microbiology and Mushroom Research Division, CSIR-Food Research Institute, Accra, Ghana.
- Department of Nutrition and Food Science, University of Ghana, Accra, Ghana.
- Food and Health Institute Strategic Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK.
| | - Maria Diaz
- Food and Health Institute Strategic Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
| | - Kwaku Tano-Debrah
- Department of Nutrition and Food Science, University of Ghana, Accra, Ghana
| | | | - Melinda J Mayer
- Gut Microbes and Health Institute Strategic Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
| | - Lizbeth Sayavedra
- Gut Microbes and Health Institute Strategic Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
| | - Collins Misita
- Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Accra, Ghana
| | - Wisdom Amoa-Awua
- Food Microbiology and Mushroom Research Division, CSIR-Food Research Institute, Accra, Ghana
- Department of Agro-Processing Technology and Food Bio-Sciences, CSIR College of Science and Technology, Accra, Ghana
| | - Arjan Narbad
- Food and Health Institute Strategic Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
- Gut Microbes and Health Institute Strategic Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
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3
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Vandermeulen MD, Cullen PJ. Ecological inducers of the yeast filamentous growth pathway reveal environment-dependent roles for pathway components. mSphere 2023; 8:e0028423. [PMID: 37732804 PMCID: PMC10597418 DOI: 10.1128/msphere.00284-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 07/31/2023] [Indexed: 09/22/2023] Open
Abstract
Signaling modules, such as mitogen-activated protein kinase (MAPK) pathways, are evolutionarily conserved drivers of cell differentiation and stress responses. In many fungal species including pathogens, MAPK pathways control filamentous growth, where cells differentiate into an elongated cell type. The convenient model budding yeast Saccharomyces cerevisiae undergoes filamentous growth by the filamentous growth (fMAPK) pathway; however, the inducers of the pathway remain unclear, perhaps because pathway activity has been mainly studied in laboratory conditions. To address this knowledge gap, an ecological framework was used, which uncovered new fMAPK pathway inducers, including pectin, a material found in plants, and the metabolic byproduct ethanol. We also show that induction by a known inducer of the pathway, the non-preferred carbon source galactose, required galactose metabolism and induced the pathway differently than glucose limitation or other non-preferred carbon sources. By exploring fMAPK pathway function in fruit, we found that induction of the pathway led to visible digestion of fruit rind through a known target, PGU1, which encodes a pectolytic enzyme. Combinations of inducers (galactose and ethanol) stimulated the pathway to near-maximal levels, which showed dispensability of several fMAPK pathway components (e.g., mucin sensor, p21-activated kinase), but not others (e.g., adaptor, MAPKKK) and required the Ras2-protein kinase A pathway. This included a difference between the transcription factor binding partners for the pathway, as Tec1p, but not Ste12p, was partly dispensable for fMAPK pathway activity. Thus, by exploring ecologically relevant stimuli, new modes of MAPK pathway signaling were uncovered, perhaps revealing how a pathway can respond differently to specific environments. IMPORTANCE Filamentous growth is a cell differentiation response and important aspect of fungal biology. In plant and animal fungal pathogens, filamentous growth contributes to virulence. One signaling pathway that regulates filamentous growth is an evolutionarily conserved MAPK pathway. The yeast Saccharomyces cerevisiae is a convenient model to study MAPK-dependent regulation of filamentous growth, although the inducers of the pathway are not clear. Here, we exposed yeast cells to ecologically relevant compounds (e.g., plant compounds), which identified new inducers of the MAPK pathway. In combination, the inducers activated the pathway to near-maximal levels but did not cause detrimental phenotypes associated with previously identified hyperactive alleles. This context allowed us to identify conditional bypass for multiple pathway components. Thus, near-maximal induction of a MAPK pathway by ecologically relevant inducers provides a powerful tool to assess cellular signaling during a fungal differentiation response.
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Affiliation(s)
| | - Paul J. Cullen
- Department of Biological Sciences, University at Buffalo, Buffalo, New York, USA
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4
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El-Khatib S, Lambert MG, Reed MN, Goncalves MB, Boynton PJ. Leaf decomposing fungi influence Saccharomyces paradoxus growth across carbon environments. MICROPUBLICATION BIOLOGY 2023; 2023:10.17912/micropub.biology.000739. [PMID: 36926040 PMCID: PMC10011917 DOI: 10.17912/micropub.biology.000739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 02/20/2023] [Accepted: 02/24/2023] [Indexed: 03/18/2023]
Abstract
Saccharomyces paradoxus is a model organism in ecology and evolution. However, its metabolism in its native habitat remains mysterious: it is frequently found growing on leaf litter, a habitat with few carbon sources that S. paradoxus can metabolize. We hypothesized that leaf-decomposing fungi from the same habitat break down the cellulose in leaf litter extracellularly and release glucose, supporting S. paradoxus growth. We found that facilitation by leaf-decomposing fungi was possible on cellulose and inhibition was common on glucose, suggesting diverse interactions between S. paradoxus and other fungi that have the potential to support S. paradoxus in nature.
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Affiliation(s)
- Samer El-Khatib
- Biology, Wheaton College - Massachusetts, Norton, Massachusetts, United States
| | - Madeleine G Lambert
- Biology, Wheaton College - Massachusetts, Norton, Massachusetts, United States.,Georgetown University Medical Center, Washington D.C., Washington, D.C., United States
| | - Meghan N Reed
- Biology, Wheaton College - Massachusetts, Norton, Massachusetts, United States.,Lonza (United States), Portsmouth, New Hampshire, United States
| | - Melane Brito Goncalves
- Biology, Wheaton College - Massachusetts, Norton, Massachusetts, United States.,Rhode Island College, Providence, Rhode Island, United States
| | - Primrose J Boynton
- Biology, Wheaton College - Massachusetts, Norton, Massachusetts, United States
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5
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Mozzachiodi S, Bai FY, Baldrian P, Bell G, Boundy-Mills K, Buzzini P, Čadež N, Riffo FC, Dashko S, Dimitrov R, Fisher KJ, Gibson BR, Gouliamova D, Greig D, Heistinger L, Hittinger CT, Jecmenica M, Koufopanou V, Landry CR, Mašínová T, Naumova ES, Opulente D, Peña JJ, Petrovič U, Tsai IJ, Turchetti B, Villarreal P, Yurkov A, Liti G, Boynton P. Yeasts from temperate forests. Yeast 2022; 39:4-24. [PMID: 35146791 DOI: 10.1002/yea.3699] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Yeasts are ubiquitous in temperate forests. While this broad habitat is well-defined, the yeasts inhabiting it and their life cycles, niches, and contributions to ecosystem functioning are less understood. Yeasts are present on nearly all sampled substrates in temperate forests worldwide. They associate with soils, macroorganisms, and other habitats, and no doubt contribute to broader ecosystem-wide processes. Researchers have gathered information leading to hypotheses about yeasts' niches and their life cycles based on physiological observations in the laboratory as well as genomic analyses, but the challenge remains to test these hypotheses in the forests themselves. Here we summarize the habitat and global patterns of yeast diversity, give some information on a handful of well-studied temperate forest yeast genera, discuss the various strategies to isolate forest yeasts, and explain temperate forest yeasts' contributions to biotechnology. We close with a summary of the many future directions and outstanding questions facing researchers in temperate forest yeast ecology. Yeasts present an exciting opportunity to better understand the hidden world of microbial ecology in this threatened and global habitat.
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Affiliation(s)
| | - Feng-Yan Bai
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Petr Baldrian
- Laboratory of Environmental Microbiology, Institute of Microbiology of the Czech Academy of Sciences, Praha 4, Czech Republic
| | - Graham Bell
- Biology Department and Redpath Museum, McGill University, Québec, Canada
| | - Kyria Boundy-Mills
- Department of Food Science and Technology, University of California Davis, Davis, CA, USA
| | - Pietro Buzzini
- Department of Agriculture, Food and Environmental Sciences & Industrial Yeasts Collection DBVPG, University of Perugia, Italy
| | - Neža Čadež
- Biotechnical Faculty, Food Science and Technology Department, University of Ljubljana, Ljubljana, Slovenia
| | - Francisco Cubillos Riffo
- Universidad de Santiago de Chile, Facultad de Química y Biología, Departamento de Biología, Santiago, Chile.,Millennium Institute for Integrative Biology (iBio), Santiago, Chile
| | - Sofia Dashko
- DSM Food Specialties, Center for Food Innovation, AX, Delft, The Netherlands
| | - Roumen Dimitrov
- Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Kaitlin J Fisher
- Laboratory of Genetics, Wisconsin Energy Institute, DOE Great Lakes Bioenergy Research Center, Center for Genomic Science Innovation, J. F. Crow Institute for the Study of Evolution, University of Wisconsin-Madison, Madison, WI, USA
| | - Brian R Gibson
- Technische Universität Berlin, Institute of Food Technology and Food Chemistry, Chair of Brewing and Beverage Technology, Berlin, Germany
| | - Dilnora Gouliamova
- Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Duncan Greig
- Centre for Life's Origins and Evolution, University College London, London, UK
| | - Lina Heistinger
- ETH Zurich, Department of Biology, Institute of Biochemistry, Switzerland
| | - Chris Todd Hittinger
- Laboratory of Genetics, Wisconsin Energy Institute, DOE Great Lakes Bioenergy Research Center, Center for Genomic Science Innovation, J. F. Crow Institute for the Study of Evolution, University of Wisconsin-Madison, Madison, WI, USA
| | | | | | - Christian R Landry
- Département de Biochimie, de Microbiologie et de Bio-informatique, Faculté des Sciences et de Génie, Université Laval, Canada.,Institut de Biologie Intégrative et des Systèmes, Université Laval, Canada.,PROTEO, Le regroupement québécois de recherche sur la fonction, l'ingénierie et les applications des protéines, Université Laval, Canada.,Centre de Recherche sur les Données Massives, Université Laval, Canada.,Département de Biologie, Faculté des Sciences et de Génie, Université Laval, Canada
| | - Tereza Mašínová
- Laboratory of Environmental Microbiology, Institute of Microbiology of the Czech Academy of Sciences, Praha 4, Czech Republic
| | - Elena S Naumova
- State Research Institute of Genetics and Selection of Industrial Microorganisms of National Research Centre "Kurchatov Institute", Moscow, Russia
| | - Dana Opulente
- Department of Biology, Villanova University, Villanova, Pennsylvania, USA
| | | | - Uroš Petrovič
- Biotechnical Faculty, Department of Biology, University of Ljubljana, Ljubljana, Slovenia.,Jožef Stefan Institute, Department of Molecular and Biomedical Sciences, Ljubljana, Slovenia
| | | | - Benedetta Turchetti
- Department of Agriculture, Food and Environmental Sciences & Industrial Yeasts Collection DBVPG, University of Perugia, Italy
| | - Pablo Villarreal
- Universidad de Santiago de Chile, Facultad de Química y Biología, Departamento de Biología, Santiago, Chile.,Millennium Institute for Integrative Biology (iBio), Santiago, Chile
| | - Andrey Yurkov
- Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Gianni Liti
- Université Côte d'Azur, CNRS, INSERM, IRCAN, Nice, France
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6
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Alsammar H, Delneri D. An update on the diversity, ecology and biogeography of the Saccharomyces genus. FEMS Yeast Res 2021; 20:5810663. [PMID: 32196094 PMCID: PMC7150579 DOI: 10.1093/femsyr/foaa013] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 03/19/2020] [Indexed: 12/14/2022] Open
Abstract
Saccharomyces cerevisiae is the most extensively studied yeast and, over the last century, provided insights on the physiology, genetics, cellular biology and molecular mechanisms of eukaryotes. More recently, the increase in the discovery of wild strains, species and hybrids of the genus Saccharomyces has shifted the attention towards studies on genome evolution, ecology and biogeography, with the yeast becoming a model system for population genomic studies. The genus currently comprises eight species, some of clear industrial importance, while others are confined to natural environments, such as wild forests devoid from human domestication activities. To date, numerous studies showed that some Saccharomyces species form genetically diverged populations that are structured by geography, ecology or domestication activity and that the yeast species can also hybridize readily both in natural and domesticated environments. Much emphasis is now placed on the evolutionary process that drives phenotypic diversity between species, hybrids and populations to allow adaptation to different niches. Here, we provide an update of the biodiversity, ecology and population structure of the Saccharomyces species, and recapitulate the current knowledge on the natural history of Saccharomyces genus.
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Affiliation(s)
- Haya Alsammar
- Department of Biological Sciences, Faculty of Science, Kuwait University, P. O. Box 5969, Safat 13060, Kuwait
| | - Daniela Delneri
- Manchester Institute of Biotechnology, Faculty of Biology Medicine and Health, The University of Manchester, Manchester, M1 7DN, UK
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7
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Boynton PJ, Wloch‐Salamon D, Landermann D, Stukenbrock EH. Forest Saccharomyces paradoxus are robust to seasonal biotic and abiotic changes. Ecol Evol 2021; 11:6604-6619. [PMID: 34141244 PMCID: PMC8207440 DOI: 10.1002/ece3.7515] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 02/25/2021] [Accepted: 03/16/2021] [Indexed: 01/02/2023] Open
Abstract
Microorganisms are famous for adapting quickly to new environments. However, most evidence for rapid microbial adaptation comes from laboratory experiments or domesticated environments, and it is unclear how rates of adaptation scale from human-influenced environments to the great diversity of wild microorganisms. We examined potential monthly-scale selective pressures in the model forest yeast Saccharomyces paradoxus. Contrary to expectations of seasonal adaptation, the S. paradoxus population was stable over four seasons in the face of abiotic and biotic environmental changes. While the S. paradoxus population was diverse, including 41 unique genotypes among 192 sampled isolates, there was no correlation between S. paradoxus genotypes and seasonal environments. Consistent with observations from other S. paradoxus populations, the forest population was highly clonal and inbred. This lack of recombination, paired with population stability, implies that selection is not acting on the forest S. paradoxus population on a seasonal timescale. Saccharomyces paradoxus may instead have evolved generalism or phenotypic plasticity with regard to seasonal environmental changes long ago. Similarly, while the forest population included diversity among phenotypes related to intraspecific interference competition, there was no evidence for active coevolution among these phenotypes. At least ten percent of the forest S. paradoxus individuals produced "killer toxins," which kill sensitive Saccharomyces cells, but the presence of a toxin-producing isolate did not predict resistance to the toxin among nearby isolates. How forest yeasts acclimate to changing environments remains an open question, and future studies should investigate the physiological responses that allow microbial cells to cope with environmental fluctuations in their native habitats.
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Affiliation(s)
- Primrose J. Boynton
- Biology DepartmentWheaton CollegeNortonMAUSA
- Environmental Genomics Research GroupMax‐Planck Institute for Evolutionary BiologyPlönGermany
| | - Dominika Wloch‐Salamon
- Faculty of BiologyInstitute of Environmental SciencesJagiellonian UniversityKrakówPoland
| | - Doreen Landermann
- Environmental Genomics Research GroupMax‐Planck Institute for Evolutionary BiologyPlönGermany
| | - Eva H. Stukenbrock
- Environmental Genomics Research GroupMax‐Planck Institute for Evolutionary BiologyPlönGermany
- Botanical InstituteChristian‐Albrechts UniversitätKielGermany
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8
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Chapagain P, Walker D, Leeds T, Cleveland BM, Salem M. Distinct microbial assemblages associated with genetic selection for high- and low- muscle yield in rainbow trout. BMC Genomics 2020; 21:820. [PMID: 33228584 PMCID: PMC7684950 DOI: 10.1186/s12864-020-07204-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 10/29/2020] [Indexed: 12/27/2022] Open
Abstract
Background Fish gut microbial assemblages play a crucial role in the growth rate, metabolism, and immunity of the host. We hypothesized that the gut microbiota of rainbow trout was correlated with breeding program based genetic selection for muscle yield. To test this hypothesis, fecal samples from 19 fish representing an F2 high-muscle genetic line (ARS-FY-H) and 20 fish representing an F1 low-muscle yield genetic line (ARS-FY-L) were chosen for microbiota profiling using the 16S rRNA gene. Significant differences in microbial assemblages between these two genetic lines might represent the effect of host genetic selection in structuring the gut microbiota of the host. Results Tukey’s transformed inverse Simpson indices indicated that high muscle yield genetic line (ARS-FY-H) samples have higher microbial diversity compared to those of the low muscle yield genetic line (ARS-FY-L) (LMM, χ2(1) =14.11, p < 0.05). The fecal samples showed statistically distinct structure in microbial assemblages between the genetic lines (F1,36 = 4.7, p < 0.05, R2 = 11.9%). Functional profiling of bacterial operational taxonomic units predicted characteristic functional capabilities of the microbial communities in the high (ARS-FY-H) and low (ARS-FY-L) muscle yield genetic line samples. Conclusion The significant differences of the microbial assemblages between high (ARS-FY-H) and low (ARS-FY-L) muscle yield genetic lines indicate a possible effect of genetic selection on the microbial diversity of the host. The functional composition of taxa demonstrates a correlation between bacteria and improving the muscle accretion in the host, probably, by producing various metabolites and enzymes that might aid in digestion. Further research is required to elucidate the mechanisms involved in shaping the microbial community through host genetic selection. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-020-07204-7.
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Affiliation(s)
- Pratima Chapagain
- Department of Biology and Molecular Biosciences Program, Middle Tennessee State University, Murfreesboro, TN, 37132, USA
| | - Donald Walker
- Department of Biology and Molecular Biosciences Program, Middle Tennessee State University, Murfreesboro, TN, 37132, USA
| | - Tim Leeds
- National Center for Cool and Cold-Water Aquaculture, ARS-USDA, Kearneysville, WV, 25430, USA
| | - Beth M Cleveland
- National Center for Cool and Cold-Water Aquaculture, ARS-USDA, Kearneysville, WV, 25430, USA
| | - Mohamed Salem
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD, 20742-231, USA.
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9
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Walker DM, Hill AJ, Albecker MA, McCoy MW, Grisnik M, Romer A, Grajal-Puche A, Camp C, Kelehear C, Wooten J, Rheubert J, Graham SP. Variation in the Slimy Salamander (Plethodon spp.) Skin and Gut-Microbial Assemblages Is Explained by Geographic Distance and Host Affinity. MICROBIAL ECOLOGY 2020; 79:985-997. [PMID: 31802185 DOI: 10.1007/s00248-019-01456-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 10/23/2019] [Indexed: 06/10/2023]
Abstract
A multicellular host and its microbial communities are recognized as a metaorganism-a composite unit of evolution. Microbial communities have a variety of positive and negative effects on the host life history, ecology, and evolution. This study used high-throughput amplicon sequencing to characterize the complete skin and gut microbial communities, including both bacteria and fungi, of a terrestrial salamander, Plethodon glutinosus (Family Plethodontidae). We assessed salamander populations, representing nine mitochondrial haplotypes ('clades'), for differences in microbial assemblages across 13 geographic locations in the Southeastern United States. We hypothesized that microbial assemblages were structured by both host factors and geographic distance. We found a strong correlation between all microbial assemblages at close geographic distances, whereas, as spatial distance increases, the patterns became increasingly discriminate. Network analyses revealed that gut-bacterial communities have the highest degree of connectedness across geographic space. Host salamander clade was explanatory of skin-bacterial and gut-fungal assemblages but not gut-bacterial assemblages, unless the latter were analyzed within a phylogenetic context. We also inferred the function of gut-fungal assemblages to understand how an understudied component of the gut microbiome may influence salamander life history. We concluded that dispersal limitation may in part describe patterns in microbial assemblages across space and also that the salamander host may select for skin and gut communities that are maintained over time in closely related salamander populations.
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Affiliation(s)
- Donald M Walker
- Department of Biology, Middle Tennessee State University, PO Box 60, Murfreesboro, TN, 37132, USA.
| | - Aubree J Hill
- Department of Biology, Tennessee Technological University, 1100 N. Dixie Ave, Cookeville, TN, 38505, USA
| | - Molly A Albecker
- Department of Biology, East Carolina University, Greenville, NC, 27858, USA
| | - Michael W McCoy
- Department of Biology, East Carolina University, Greenville, NC, 27858, USA
| | - Matthew Grisnik
- Department of Biology, Middle Tennessee State University, PO Box 60, Murfreesboro, TN, 37132, USA
| | - Alexander Romer
- Department of Biology, Middle Tennessee State University, PO Box 60, Murfreesboro, TN, 37132, USA
| | - Alejandro Grajal-Puche
- Department of Biology, Middle Tennessee State University, PO Box 60, Murfreesboro, TN, 37132, USA
| | - Carlos Camp
- Department of Biology, Piedmont College, 1021 Central Avenue, Demorest, GA, 30535, USA
| | - Crystal Kelehear
- Smithsonian Tropical Research Institute, Apartado, 0843-03092, Balboa, Ancon, Panama, Republic of Panama
- Department of Biology, Geology and Physical Sciences, Sul Ross State University, Alpine, TX, 79832, USA
| | - Jessica Wooten
- Department of Biology, Piedmont College, 1021 Central Avenue, Demorest, GA, 30535, USA
| | - Justin Rheubert
- Department of Natural Sciences, The University of Findlay, 1000 N. Main St, Findlay, OH, 45840, USA
| | - Sean P Graham
- Department of Biology, Geology and Physical Sciences, Sul Ross State University, Alpine, TX, 79832, USA
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10
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Competition experiments in a soil microcosm reveal the impact of genetic and biotic factors on natural yeast populations. ISME JOURNAL 2020; 14:1410-1421. [PMID: 32080356 DOI: 10.1038/s41396-020-0612-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 02/03/2020] [Accepted: 02/07/2020] [Indexed: 02/06/2023]
Abstract
The ability to measure microbial fitness directly in natural conditions and in interaction with other microbes is a challenge that needs to be overcome if we want to gain a better understanding of microbial fitness determinants in nature. Here we investigate the influence of the natural microbial community on the relative fitness of the North American populations SpB, SpC and SpC* of the wild yeast Saccharomyces paradoxus using DNA barcodes and a soil microcosm derived from soil associated with oak trees. We find that variation in fitness among these genetically distinct groups is influenced by the microbial community. Altering the microbial community load and diversity with an irradiation treatment significantly diminishes the magnitude of fitness differences among populations. Our findings suggest that microbial interactions could affect the evolution of yeast lineages in nature by modulating variation in fitness.
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11
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mSphere of Influence: the Wild Genetic Diversity of Our Closest Yeast Companions. mSphere 2019; 4:4/5/e00650-19. [PMID: 31554728 PMCID: PMC6763774 DOI: 10.1128/msphere.00650-19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Douda Bensasson uses the population genomics of model yeast species to understand how wild yeast colonize new environments, such as humans or their food. In this mSphere of Influence article, she reflects on how the discovery of “Surprisingly diverged populations of Saccharomyces cerevisiae in natural environments remote from human activity” (Q.-M. Wang, W.-Q. Liu, G. Liti, S.-A. Wang, and F.-Y. Douda Bensasson uses the population genomics of model yeast species to understand how wild yeast colonize new environments, such as humans or their food. In this mSphere of Influence article, she reflects on how the discovery of “Surprisingly diverged populations of Saccharomyces cerevisiae in natural environments remote from human activity” (Q.-M. Wang, W.-Q. Liu, G. Liti, S.-A. Wang, and F.-Y. Bai, Mol Ecol 21:5404–5417, 2012, https://doi.org/10.1111/j.1365-294X.2012.05732.x) showed that a field survey and population genetic analysis of old growth forests could “unveil the hidden part of the iceberg” of natural variation in S. cerevisiae that went unnoticed for over a hundred years of yeast research.
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12
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Boynton PJ, Kowallik V, Landermann D, Stukenbrock EH. Quantifying the efficiency and biases of forest Saccharomyces sampling strategies. Yeast 2019; 36:657-668. [PMID: 31348543 DOI: 10.1002/yea.3435] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 07/18/2019] [Accepted: 07/19/2019] [Indexed: 12/12/2022] Open
Abstract
Saccharomyces yeasts are emerging as model organisms for ecology and evolution, and researchers need environmental Saccharomyces isolates to test ecological and evolutionary hypotheses. However, methods for isolating Saccharomyces from nature have not been standardized, and isolation methods may influence the genotypes and phenotypes of studied strains. We compared the effectiveness and potential biases of an established enrichment culturing method against a newly developed direct plating method for isolating forest floor Saccharomyces spp. In a European forest, enrichment culturing was both less successful at isolating Saccharomyces paradoxus per sample collected and less labour intensive per isolated S. paradoxus colony than direct isolation. The two methods sampled similar S. paradoxus diversity: The number of unique genotypes sampled (i.e., genotypic diversity) per S. paradoxus isolate and average growth rates of S. paradoxus isolates did not differ between the two methods, and growth rate variances (i.e., phenotypic diversity) only differed in one of three tested environments. However, enrichment culturing did detect rare Saccharomyces cerevisiae in the forest habitat and also found two S. paradoxus isolates with outlier phenotypes. Our results validate the historically common method of using enrichment culturing to isolate representative collections of environmental Saccharomyces. We recommend that researchers choose a Saccharomyces sampling method based on resources available for sampling and isolate screening. Researchers interested in discovering new Saccharomyces phenotypes or rare Saccharomyces species from natural environments may also have more success using enrichment culturing. We include step-by-step sampling protocols in the supplemental materials.
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Affiliation(s)
- Primrose J Boynton
- Environmental Genomics Research Group, Max-Planck Institute for Evolutionary Biology, Plön, Germany
| | - Vienna Kowallik
- Ecology and Evolution Unit, Okinawa Institute of Science and Technology, Okinawa, Japan
| | - Doreen Landermann
- Environmental Genomics Research Group, Max-Planck Institute for Evolutionary Biology, Plön, Germany
| | - Eva H Stukenbrock
- Environmental Genomics Research Group, Max-Planck Institute for Evolutionary Biology, Plön, Germany.,Botanisches Institut, Christian-Albrechts Universität, Botanisches Institut, Kiel, Germany
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13
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Legras JL, Galeote V, Bigey F, Camarasa C, Marsit S, Nidelet T, Sanchez I, Couloux A, Guy J, Franco-Duarte R, Marcet-Houben M, Gabaldon T, Schuller D, Sampaio JP, Dequin S. Adaptation of S. cerevisiae to Fermented Food Environments Reveals Remarkable Genome Plasticity and the Footprints of Domestication. Mol Biol Evol 2019; 35:1712-1727. [PMID: 29746697 PMCID: PMC5995190 DOI: 10.1093/molbev/msy066] [Citation(s) in RCA: 139] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The budding yeast Saccharomyces cerevisiae can be found in the wild and is also frequently associated with human activities. Despite recent insights into the phylogeny of this species, much is still unknown about how evolutionary processes related to anthropogenic niches have shaped the genomes and phenotypes of S. cerevisiae. To address this question, we performed population-level sequencing of 82 S. cerevisiae strains from wine, flor, rum, dairy products, bakeries, and the natural environment (oak trees). These genomic data enabled us to delineate specific genetic groups corresponding to the different ecological niches and revealed high genome content variation across the groups. Most of these strains, compared with the reference genome, possessed additional genetic elements acquired by introgression or horizontal transfer, several of which were population-specific. In addition, several genomic regions in each population showed evidence of nonneutral evolution, as shown by high differentiation, or of selective sweeps including genes with key functions in these environments (e.g., amino acid transport for wine yeast). Linking genetics to lifestyle differences and metabolite traits has enabled us to elucidate the genetic basis of several niche-specific population traits, such as growth on galactose for cheese strains. These data indicate that yeast has been subjected to various divergent selective pressures depending on its niche, requiring the development of customized genomes for better survival in these environments. These striking genome dynamics associated with local adaptation and domestication reveal the remarkable plasticity of the S. cerevisiae genome, revealing this species to be an amazing complex of specialized populations.
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Affiliation(s)
- Jean-Luc Legras
- SPO, Univ Montpellier, INRA, Montpellier SupAgro, Montpellier, France
| | - Virginie Galeote
- SPO, Univ Montpellier, INRA, Montpellier SupAgro, Montpellier, France
| | - Frédéric Bigey
- SPO, Univ Montpellier, INRA, Montpellier SupAgro, Montpellier, France
| | - Carole Camarasa
- SPO, Univ Montpellier, INRA, Montpellier SupAgro, Montpellier, France
| | - Souhir Marsit
- SPO, Univ Montpellier, INRA, Montpellier SupAgro, Montpellier, France
| | - Thibault Nidelet
- SPO, Univ Montpellier, INRA, Montpellier SupAgro, Montpellier, France
| | | | - Arnaud Couloux
- Centre National de Séquençage, Institut de Genomique, Genoscope, Evry Cedex, France
| | - Julie Guy
- Centre National de Séquençage, Institut de Genomique, Genoscope, Evry Cedex, France
| | - Ricardo Franco-Duarte
- CBMA, Department of Biology, Universidade do Minho, Campus de Gualtar, Braga, Portugal
| | - Marina Marcet-Houben
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Toni Gabaldon
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain.,ICREA, Pg. Lluís Companys 23, Barcelona, Spain
| | - Dorit Schuller
- CBMA, Department of Biology, Universidade do Minho, Campus de Gualtar, Braga, Portugal
| | - José Paulo Sampaio
- UCIBIO-REQUIMTE, Departamento de Ciencias da Vida, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal
| | - Sylvie Dequin
- SPO, Univ Montpellier, INRA, Montpellier SupAgro, Montpellier, France
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14
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Alsammar HF, Naseeb S, Brancia LB, Gilman RT, Wang P, Delneri D. Targeted metagenomics approach to capture the biodiversity of Saccharomyces genus in wild environments. ENVIRONMENTAL MICROBIOLOGY REPORTS 2019; 11:206-214. [PMID: 30507071 PMCID: PMC6767435 DOI: 10.1111/1758-2229.12724] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 11/15/2018] [Accepted: 11/15/2018] [Indexed: 06/09/2023]
Abstract
The species of the genus Saccharomyces are commonly inhabiting tree bark and the surrounding soil, but their abundance have likely been underestimated due to biases in culturing methods. Metagenomic studies have so far been unable to detect Saccharomyces species in wild environments. Here, we sequenced the mycobiome of soils surrounding different trees at various altitudes in the Italian Alps. To survey for yeasts species belonging to Saccharomyces genus rather than other fungal species, we performed a selectivity step involving the isolation of the internal transcribed spacer (ITS) region that is specific to this yeast group. Reads mapping to Saccharomyces species were detected in all soil samples, including reads for S. mikatae and for S. eubayanus. ITS1 alignment of the S. cerevisiae, S. paradoxus and S. kudriavzevii sequences showed up to three base pair polymorphisms with other known strains, indicating possible new lineages. Basidiomycetous fungi were still the dominant species, compared to the Ascomycota, but the selectivity step allowed for the first time the detection and study of the biodiversity of the Saccharomyces species in their natural environment.
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Affiliation(s)
- Haya F. Alsammar
- Manchester Institute of Biotechnology, Faculty of Biology Medicine and HealthThe University of ManchesterManchesterM1 7DNUK
| | - Samina Naseeb
- Manchester Institute of Biotechnology, Faculty of Biology Medicine and HealthThe University of ManchesterManchesterM1 7DNUK
| | | | - R. Tucker Gilman
- School of Earth and Environmental Sciences, Faculty of Science and EngineeringThe University of ManchesterManchesterM13 9PLUK
| | - Ping Wang
- Genomic Core Facility, Faculty of Biology Medicine and HealthThe University of ManchesterManchesterM13 9PLUK
| | - Daniela Delneri
- Manchester Institute of Biotechnology, Faculty of Biology Medicine and HealthThe University of ManchesterManchesterM1 7DNUK
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15
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Bensasson D, Dicks J, Ludwig JM, Bond CJ, Elliston A, Roberts IN, James SA. Diverse Lineages of Candida albicans Live on Old Oaks. Genetics 2019; 211:277-288. [PMID: 30463870 PMCID: PMC6325710 DOI: 10.1534/genetics.118.301482] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 11/05/2018] [Indexed: 12/26/2022] Open
Abstract
The human pathogen Candida albicans is considered an obligate commensal of animals, yet it is occasionally isolated from trees, shrubs, and grass. We generated genome sequence data for three strains of C. albicans that we isolated from oak trees in an ancient wood pasture, and compared these to the genomes of over 200 clinical strains. C. albicans strains from oak are similar to clinical C. albicans in that they are predominantly diploid and can become homozygous at the mating locus through whole-chromosome loss of heterozygosity. Oak strains differed from clinical strains in showing slightly higher levels of heterozygosity genome-wide. Using phylogenomic analyses and in silico chromosome painting, we show that each oak strain is more closely related to strains from humans and other animals than to strains from other oaks. The high genetic diversity of C. albicans from old oaks shows that they can live in this environment for extended periods of time.
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Affiliation(s)
- Douda Bensasson
- Department of Plant Biology, University of Georgia, Athens, Georgia 30602
- Institute of Bioinformatics, University of Georgia, Athens, Georgia 30602
| | - Jo Dicks
- National Collection of Yeast Cultures, Quadram Institute Bioscience, Norwich NR4 7UA, UK
| | - John M Ludwig
- Institute of Bioinformatics, University of Georgia, Athens, Georgia 30602
| | - Christopher J Bond
- National Collection of Yeast Cultures, Quadram Institute Bioscience, Norwich NR4 7UA, UK
| | - Adam Elliston
- National Collection of Yeast Cultures, Quadram Institute Bioscience, Norwich NR4 7UA, UK
| | - Ian N Roberts
- National Collection of Yeast Cultures, Quadram Institute Bioscience, Norwich NR4 7UA, UK
| | - Stephen A James
- National Collection of Yeast Cultures, Quadram Institute Bioscience, Norwich NR4 7UA, UK
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16
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Bleuven C, Dubé AK, Nguyen GQ, Gagnon‐Arsenault I, Martin H, Landry CR. A collection of barcoded natural isolates of Saccharomyces paradoxus to study microbial evolutionary ecology. Microbiologyopen 2018; 8:e00773. [PMID: 30569485 PMCID: PMC6612553 DOI: 10.1002/mbo3.773] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 11/05/2018] [Accepted: 11/06/2018] [Indexed: 01/24/2023] Open
Abstract
While the use of barcoded collections of laboratory microorganisms and the development of barcode-based cell tracking are rapidly developing in genetics and genomics research, tools to track natural populations are still lacking. The yeast Saccharomyces paradoxus is an emergent microbial model in ecology and evolution. More than five allopatric and sympatric lineages have been identified and hundreds of strains have been isolated for this species, allowing to assess the impact of natural diversity on complex traits. We constructed a collection of 550 barcoded and traceable strains of S. paradoxus, including all three North American lineages SpB, SpC, and SpC*. These strains are diploid, many have their genome fully sequenced and are barcoded with a unique 20 bp sequence that allows their identification and quantification. This yeast collection is functional for competitive experiments in pools as the barcodes allow to measure each lineage's and individual strains' fitness in common conditions. We used this tool to demonstrate that in the tested conditions, there are extensive genotype-by-environment interactions for fitness among S. paradoxus strains, which reveals complex evolutionary potential in variable environments. This barcoded collection provides a valuable resource for ecological genomics studies that will allow gaining a better understanding of S. paradoxus evolution and fitness-related traits.
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Affiliation(s)
- Clara Bleuven
- Département de BiologieUniversité LavalQuébecQuébecCanada,Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQuébecCanada,Big Data Research CenterUniversité LavalQuébecQuébecCanada,PROTEO, The Quebec Network for Research on Protein Function, Engineering, and ApplicationsQuébecQuébecCanada
| | - Alexandre K. Dubé
- Département de BiologieUniversité LavalQuébecQuébecCanada,Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQuébecCanada,Big Data Research CenterUniversité LavalQuébecQuébecCanada,PROTEO, The Quebec Network for Research on Protein Function, Engineering, and ApplicationsQuébecQuébecCanada,Département de Biochimiede Microbiologie et de Bio‐informatique, Université LavalQuébecQuébecCanada
| | - Guillaume Q. Nguyen
- Département de BiologieUniversité LavalQuébecQuébecCanada,Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQuébecCanada,Big Data Research CenterUniversité LavalQuébecQuébecCanada,PROTEO, The Quebec Network for Research on Protein Function, Engineering, and ApplicationsQuébecQuébecCanada,Département des Sciences des aliments, Institut sur la nutrition et les aliments fonctionnels (INAF)Université LavalQuébecQuébecCanada
| | - Isabelle Gagnon‐Arsenault
- Département de BiologieUniversité LavalQuébecQuébecCanada,Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQuébecCanada,Big Data Research CenterUniversité LavalQuébecQuébecCanada,PROTEO, The Quebec Network for Research on Protein Function, Engineering, and ApplicationsQuébecQuébecCanada,Département de Biochimiede Microbiologie et de Bio‐informatique, Université LavalQuébecQuébecCanada
| | - Hélène Martin
- Département de BiologieUniversité LavalQuébecQuébecCanada,Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQuébecCanada,Big Data Research CenterUniversité LavalQuébecQuébecCanada,PROTEO, The Quebec Network for Research on Protein Function, Engineering, and ApplicationsQuébecQuébecCanada,Département de Biochimiede Microbiologie et de Bio‐informatique, Université LavalQuébecQuébecCanada
| | - Christian R. Landry
- Département de BiologieUniversité LavalQuébecQuébecCanada,Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQuébecCanada,Big Data Research CenterUniversité LavalQuébecQuébecCanada,PROTEO, The Quebec Network for Research on Protein Function, Engineering, and ApplicationsQuébecQuébecCanada,Département de Biochimiede Microbiologie et de Bio‐informatique, Université LavalQuébecQuébecCanada
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17
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Kayikci Ö, Magwene PM. Divergent Roles for cAMP-PKA Signaling in the Regulation of Filamentous Growth in Saccharomyces cerevisiae and Saccharomyces bayanus. G3 (BETHESDA, MD.) 2018; 8:3529-3538. [PMID: 30213866 PMCID: PMC6222581 DOI: 10.1534/g3.118.200413] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 08/27/2018] [Indexed: 01/18/2023]
Abstract
The cyclic AMP - Protein Kinase A (cAMP-PKA) pathway is an evolutionarily conserved eukaryotic signaling network that is essential for growth and development. In the fungi, cAMP-PKA signaling plays a critical role in regulating cellular physiology and morphological switches in response to nutrient availability. We undertook a comparative investigation of the role that cAMP-PKA signaling plays in the regulation of filamentous growth in two closely related budding yeast species, Saccharomyces cerevisiae and Saccharomyces bayanus Using chemical and genetic perturbations of this pathway and its downstream targets we discovered divergent roles for cAMP-PKA signaling in the regulation of filamentous growth. While cAMP-PKA signaling is required for the filamentous growth response in both species, increasing or decreasing the activity of this pathway leads to drastically different phenotypic outcomes. In S. cerevisiae, cAMP-PKA inhibition ameliorates the filamentous growth response while hyper-activation of the pathway leads to increased filamentous growth; the same perturbations in S. bayanus result in the obverse. Divergence in the regulation of filamentous growth between S. cerevisiae and S. bayanus extends to downstream targets of PKA, including several kinases, transcription factors, and effector proteins. Our findings highlight the potential for significant evolutionary divergence in gene network function, even when the constituent parts of such networks are well conserved.
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Affiliation(s)
- Ömur Kayikci
- Department of Biology, Duke University, Durham, North Carolina
| | - Paul M Magwene
- Department of Biology, Duke University, Durham, North Carolina
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18
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Walker DM, Murray CM, Talbert D, Tinker P, Graham SP, Crowther TW. A salamander's top down effect on fungal communities in a detritivore ecosystem. FEMS Microbiol Ecol 2018; 94:5104376. [DOI: 10.1093/femsec/fiy168] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 08/17/2018] [Indexed: 12/17/2022] Open
Affiliation(s)
- Donald M Walker
- Middle Tennessee State University, Toxicology and Disease Group, Biology Department, PO Box 60, Murfreesboro, TN, USA
| | | | - Doug Talbert
- Tennessee Technological University, Department of Computer Science, Cookeville, TN, USA
| | - Paul Tinker
- Tennessee Technological University, Department of Computer Science, Cookeville, TN, USA
| | - Sean P Graham
- Sul Ross University, Department of Biology, Alpine, TX, USA
| | - Thomas W Crowther
- Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zurich, Univeritätstrasse 16, 8092 Zürich, Switzerland
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19
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Charron G, Landry CR. No evidence for extrinsic post-zygotic isolation in a wild Saccharomyces yeast system. Biol Lett 2017; 13:rsbl.2017.0197. [PMID: 28592521 DOI: 10.1098/rsbl.2017.0197] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 05/12/2017] [Indexed: 12/12/2022] Open
Abstract
Although microorganisms account for the largest fraction of Earth's biodiversity, we know little about how their reproductive barriers evolve. Sexual microorganisms such as Saccharomyces yeasts rapidly develop strong intrinsic post-zygotic isolation, but the role of extrinsic isolation in the early speciation process remains to be investigated. We measured the growth of F1 hybrids between two incipient species of Saccharomyces paradoxus to assess the presence of extrinsic post-zygotic isolation across 32 environments. More than 80% of hybrids showed either partial dominance of the best parent or over-dominance for growth, revealing no fitness defects in F1 hybrids. Extrinsic reproductive isolation therefore likely plays little role in limiting gene flow between incipient yeast species and is not a requirement for speciation.
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Affiliation(s)
- Guillaume Charron
- Institut de Biologie Intégrative et des Systèmes, Département de Biologie, PROTEO, Pavillon Charles-Eugène-Marchand, 1030 avenue de la Médecine - Université Laval, Québec, Canada G1 V 0A6
| | - Christian R Landry
- Institut de Biologie Intégrative et des Systèmes, Département de Biologie, PROTEO, Pavillon Charles-Eugène-Marchand, 1030 avenue de la Médecine - Université Laval, Québec, Canada G1 V 0A6
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20
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Marsit S, Leducq JB, Durand É, Marchant A, Filteau M, Landry CR. Evolutionary biology through the lens of budding yeast comparative genomics. Nat Rev Genet 2017; 18:581-598. [DOI: 10.1038/nrg.2017.49] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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21
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Brysch-Herzberg M, Seidel M. Distribution patterns of Saccharomyces species in cultural landscapes of Germany. FEMS Yeast Res 2017; 17:3829890. [DOI: 10.1093/femsyr/fox033] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 05/16/2017] [Indexed: 12/30/2022] Open
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22
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Filteau M, Charron G, Landry CR. Identification of the fitness determinants of budding yeast on a natural substrate. THE ISME JOURNAL 2017; 11:959-971. [PMID: 27935595 PMCID: PMC5364353 DOI: 10.1038/ismej.2016.170] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 09/15/2016] [Accepted: 10/20/2016] [Indexed: 12/21/2022]
Abstract
The budding yeasts are prime models in genomics and cell biology, but the ecological factors that determine their success in non-human-associated habitats is poorly understood. In North America Saccharomyces yeasts are present on the bark of deciduous trees, where they feed on bark and sap exudates. In the North East, Saccharomyces paradoxus is found on maples, which makes maple sap a natural substrate for this species. We measured growth rates of S. paradoxus natural isolates on maple sap and found variation along a geographical gradient not explained by the inherent variation observed under optimal laboratory conditions. We used a functional genomic screen to reveal the ecologically relevant genes and conditions required for optimal growth in this substrate. We found that the allantoin degradation pathway is required for optimal growth in maple sap, in particular genes necessary for allantoate utilization, which we demonstrate is the major nitrogen source available to yeast in this environment. Growth with allantoin or allantoate as the sole nitrogen source recapitulated the variation in growth rates in maple sap among strains. We also show that two lineages of S. paradoxus display different life-history traits on allantoin and allantoate media, highlighting the ecological relevance of this pathway.
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Affiliation(s)
- Marie Filteau
- Département de Biologie, PROTEO, Big Data Research Center and Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
- Département des Sciences des aliments, Institut sur la nutrition et les aliments fonctionnels (INAF), Université Laval, Québec, Québec, Canada
| | - Guillaume Charron
- Département de Biologie, PROTEO, Big Data Research Center and Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
| | - Christian R Landry
- Département de Biologie, PROTEO, Big Data Research Center and Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
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23
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Xia W, Nielly-Thibault L, Charron G, Landry CR, Kasimer D, Anderson JB, Kohn LM. Population genomics reveals structure at the individual, host-tree scale and persistence of genotypic variants of the undomesticated yeast Saccharomyces paradoxus in a natural woodland. Mol Ecol 2017; 26:995-1007. [PMID: 27988980 DOI: 10.1111/mec.13954] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 11/28/2016] [Indexed: 12/23/2022]
Abstract
Genetic diversity in experimental, domesticated and wild populations of the related yeasts, Saccharomyces cerevisiae and Saccharomyces paradoxus, has been well described at the global scale. We investigated the population genomics of a local population on a small spatial scale to address two main questions. First, is there genomic variation in a S. paradoxus population at a spatial scale spanning centimetres (microsites) to tens of metres? Second, does the distribution of genomic variants persist over time? Our sample consisted of 42 S. paradoxus strains from 2014 and 43 strains from 2015 collected from the same 72 microsites around four host trees (Quercus rubra and Quercus alba) within 1 km2 in a mixed hardwood forest in southern Ontario. Six additional S. paradoxus strains recovered from adjacent maple and beech trees in 2015 are also included in the sample. Whole-genome sequencing and genomic SNP analysis revealed five differentiated groups (clades) within the sampled area. The signal of persistence of genotypes in their microsites from 2014 to 2015 was highly significant. Isolates from the same tree tended to be more related than strains from different trees, with limited evidence of dispersal between trees. In growth assays, one genotype had a significantly longer lag phase than the other strains. Our results indicate that different clades coexist at fine spatial scale and that population structure persists over at least a one-year interval in these wild yeasts, suggesting the efficacy of yearly sampling to follow longer term genetic dynamics in future studies.
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Affiliation(s)
- Wenjing Xia
- Departments of Ecology and Evolutionary Biology and Cell and Systems Biology, University of Toronto Mississauga, 3359 Mississauga Rd, Mississauga, ON, L5L 1C6, Canada
| | - Lou Nielly-Thibault
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes, PROTEO, Pavillon Charles-Eugène-Marchand, Université Laval, 1030 avenue de la Médecine, Québec, QC, G1V 0A6, Canada
| | - Guillaume Charron
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes, PROTEO, Pavillon Charles-Eugène-Marchand, Université Laval, 1030 avenue de la Médecine, Québec, QC, G1V 0A6, Canada
| | - Christian R Landry
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes, PROTEO, Pavillon Charles-Eugène-Marchand, Université Laval, 1030 avenue de la Médecine, Québec, QC, G1V 0A6, Canada
| | - Dahlia Kasimer
- Departments of Ecology and Evolutionary Biology and Cell and Systems Biology, University of Toronto Mississauga, 3359 Mississauga Rd, Mississauga, ON, L5L 1C6, Canada
| | - James B Anderson
- Departments of Ecology and Evolutionary Biology and Cell and Systems Biology, University of Toronto Mississauga, 3359 Mississauga Rd, Mississauga, ON, L5L 1C6, Canada
| | - Linda M Kohn
- Departments of Ecology and Evolutionary Biology and Cell and Systems Biology, University of Toronto Mississauga, 3359 Mississauga Rd, Mississauga, ON, L5L 1C6, Canada
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Kowallik V, Greig D. A systematic forest survey showing an association of Saccharomyces paradoxus with oak leaf litter. ENVIRONMENTAL MICROBIOLOGY REPORTS 2016; 8:833-841. [PMID: 27481438 DOI: 10.1111/1758-2229.12446] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 07/19/2016] [Indexed: 06/06/2023]
Abstract
Although we understand the genetics of the laboratory model yeast Saccharomyces cerevisiae very well, we know little about the natural ecology and environment that shaped its genome. Most isolates of Saccharomyces paradoxus, the wild relative of S. cerevisiae, come from oak trees, but it is not known whether this is because oak is their primary habitat. We surveyed leaf litter in a forest in Northern Germany and found a strong correlation between isolation success of wild Saccharomyces and the proximity of the nearest oak. We compared the four most common tree genera and found Saccharomyces most frequently in oak litter. Interestingly, we show that Saccharomyces is much more abundant in oak leaf litter than on oak bark, suggesting that it grows in litter or soil rather than on the surfaces of oaks themselves. The distribution and abundance of Saccharomyces over the course of a year shows that oak leaf litter provides a stable habitat for the yeast, although there was significant tree-to-tree variation. Taken together, our results suggest that leaf litter rather than tree surfaces provide the better habitat for wild Saccharomyces, with oak being the preferred tree genus. 99.5% of all strains (633/636) isolated were S. paradoxus.
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Affiliation(s)
- Vienna Kowallik
- Experimental Evolution Group, Max Planck Institute for Evolutionary Biology, 24306 Plön, Germany
| | - Duncan Greig
- Experimental Evolution Group, Max Planck Institute for Evolutionary Biology, 24306 Plön, Germany
- Department of Genetics, Evolution, and Environment, University College London, Gower Street, London, WC1E 6BT, UK
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Boynton PJ, Stelkens R, Kowallik V, Greig D. Measuring microbial fitness in a field reciprocal transplant experiment. Mol Ecol Resour 2016; 17:370-380. [PMID: 27333260 DOI: 10.1111/1755-0998.12562] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 05/17/2016] [Accepted: 05/30/2016] [Indexed: 11/27/2022]
Abstract
Microbial fitness is easy to measure in the laboratory, but difficult to measure in the field. Laboratory fitness assays make use of controlled conditions and genetically modified organisms, neither of which are available in the field. Among other applications, fitness assays can help researchers detect adaptation to different habitats or locations. We designed a competitive fitness assay to detect adaptation of Saccharomyces paradoxus isolates to the habitat they were isolated from (oak or larch leaf litter). The assay accurately measures relative fitness by tracking genotype frequency changes in the field using digital droplet PCR (DDPCR). We expected locally adapted S. paradoxus strains to increase in frequency over time when growing on the leaf litter type from which they were isolated. The DDPCR assay successfully detected fitness differences among S. paradoxus strains, but did not find a tendency for strains to be adapted to the habitat they were isolated from. Instead, we found that the natural alleles of the hexose transport gene we used to distinguish S. paradoxus strains had significant effects on fitness. The origin of a strain also affected its fitness: strains isolated from oak litter were generally fitter than strains from larch litter. Our results suggest that dispersal limitation and genetic drift shape S. paradoxus populations in the forest more than local selection does, although further research is needed to confirm this. Tracking genotype frequency changes using DDPCR is a practical and accurate microbial fitness assay for natural environments.
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Affiliation(s)
- Primrose J Boynton
- Max Planck Institute for Evolutionary Biology, August-Thienemann-Str. 2, 24306, Plön, Germany
| | - Rike Stelkens
- Max Planck Institute for Evolutionary Biology, August-Thienemann-Str. 2, 24306, Plön, Germany
| | - Vienna Kowallik
- Max Planck Institute for Evolutionary Biology, August-Thienemann-Str. 2, 24306, Plön, Germany
| | - Duncan Greig
- Max Planck Institute for Evolutionary Biology, August-Thienemann-Str. 2, 24306, Plön, Germany.,The Galton Laboratory, Department of Genetics, Evolution, and Environment, University College London, London, WC1E 6BT, UK
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Dashko S, Liu P, Volk H, Butinar L, Piškur J, Fay JC. Changes in the Relative Abundance of Two Saccharomyces Species from Oak Forests to Wine Fermentations. Front Microbiol 2016; 7:215. [PMID: 26941733 PMCID: PMC4764737 DOI: 10.3389/fmicb.2016.00215] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 02/09/2016] [Indexed: 11/23/2022] Open
Abstract
Saccharomyces cerevisiae and its sibling species Saccharomyces paradoxus are known to inhabit temperate arboreal habitats across the globe. Despite their sympatric distribution in the wild, S. cerevisiae is predominantly associated with human fermentations. The apparent ecological differentiation of these species is particularly striking in Europe where S. paradoxus is abundant in forests and S. cerevisiae is abundant in vineyards. However, ecological differences may be confounded with geographic differences in species abundance. To compare the distribution and abundance of these two species we isolated Saccharomyces strains from over 1200 samples taken from vineyard and forest habitats in Slovenia. We isolated numerous strains of S. cerevisiae and S. paradoxus, as well as a small number of Saccharomyces kudriavzevii strains, from both vineyard and forest environments. We find S. cerevisiae less abundant than S. paradoxus on oak trees both within and outside the vineyard, but more abundant on grapevines and associated substrates. Analysis of the uncultured microbiome shows, that both S. cerevisiae and S. paradoxus are rare species in soil and bark samples, but can be much more common in grape must. In contrast to S. paradoxus, European strains of S. cerevisiae have acquired multiple traits thought to be important for life in the vineyard and dominance of wine fermentations. We conclude, that S. cerevisiae and S. paradoxus currently share both vineyard and non-vineyard habitats in Slovenia and we discuss factors relevant to their global distribution and relative abundance.
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Affiliation(s)
- Sofia Dashko
- Wine Research Center, University of Nova GoricaVipava, Slovenia; Department of Biology, Lund UniversityLund, Sweden
| | - Ping Liu
- Department of Genetics and Center for Genome Sciences and System Biology, Washington University St. Louis, MO, USA
| | - Helena Volk
- Wine Research Center, University of Nova Gorica Vipava, Slovenia
| | - Lorena Butinar
- Wine Research Center, University of Nova Gorica Vipava, Slovenia
| | - Jure Piškur
- Wine Research Center, University of Nova GoricaVipava, Slovenia; Department of Biology, Lund UniversityLund, Sweden
| | - Justin C Fay
- Department of Genetics and Center for Genome Sciences and System Biology, Washington University St. Louis, MO, USA
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27
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Stelkens RB, Miller EL, Greig D. Asynchronous spore germination in isogenic natural isolates ofSaccharomyces paradoxus. FEMS Yeast Res 2016; 16:fow012. [DOI: 10.1093/femsyr/fow012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/10/2016] [Indexed: 12/18/2022] Open
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Robinson HA, Pinharanda A, Bensasson D. Summer temperature can predict the distribution of wild yeast populations. Ecol Evol 2016; 6:1236-50. [PMID: 26941949 PMCID: PMC4761769 DOI: 10.1002/ece3.1919] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 11/30/2015] [Accepted: 12/01/2015] [Indexed: 12/23/2022] Open
Abstract
The wine yeast, Saccharomyces cerevisiae, is the best understood microbial eukaryote at the molecular and cellular level, yet its natural geographic distribution is unknown. Here we report the results of a field survey for S. cerevisiae,S. paradoxus and other budding yeast on oak trees in Europe. We show that yeast species differ in their geographic distributions, and investigated which ecological variables can predict the isolation rate of S. paradoxus, the most abundant species. We find a positive association between trunk girth and S. paradoxus abundance suggesting that older trees harbor more yeast. S. paradoxus isolation frequency is also associated with summer temperature, showing highest isolation rates at intermediate temperatures. Using our statistical model, we estimated a range of summer temperatures at which we expect high S. paradoxus isolation rates, and show that the geographic distribution predicted by this optimum temperature range is consistent with the worldwide distribution of sites where S. paradoxus has been isolated. Using laboratory estimates of optimal growth temperatures for S. cerevisiae relative to S. paradoxus, we also estimated an optimum range of summer temperatures for S. cerevisiae. The geographic distribution of these optimum temperatures is consistent with the locations where wild S. cerevisiae have been reported, and can explain why only human-associated S. cerevisiae strains are isolated at northernmost latitudes. Our results provide a starting point for targeted isolation of S. cerevisiae from natural habitats, which could lead to a better understanding of climate associations and natural history in this important model microbe.
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Affiliation(s)
| | - Ana Pinharanda
- Faculty of Life Sciences University of Manchester Manchester M13 9PT UK
| | - Douda Bensasson
- Faculty of Life Sciences University of Manchester Manchester M13 9PT UK
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Marques WL, Raghavendran V, Stambuk BU, Gombert AK. Sucrose and Saccharomyces cerevisiae: a relationship most sweet. FEMS Yeast Res 2015; 16:fov107. [PMID: 26658003 DOI: 10.1093/femsyr/fov107] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/06/2015] [Indexed: 12/16/2022] Open
Abstract
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.
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Affiliation(s)
- Wesley Leoricy Marques
- Department of Chemical Engineering, University of São Paulo, São Paulo-SP, 05424-970, Brazil School of Food Engineering, University of Campinas, Campinas-SP, 13083-862, Brazil
| | | | - Boris Ugarte Stambuk
- Department of Biochemistry, Federal University of Santa Catarina, Florianópolis-SC, 88040-900, Brazil
| | - Andreas Karoly Gombert
- Department of Chemical Engineering, University of São Paulo, São Paulo-SP, 05424-970, Brazil School of Food Engineering, University of Campinas, Campinas-SP, 13083-862, Brazil
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Goddard MR, Greig D. Saccharomyces cerevisiae: a nomadic yeast with no niche? FEMS Yeast Res 2015; 15:fov009. [PMID: 25725024 PMCID: PMC4444983 DOI: 10.1093/femsyr/fov009] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/21/2015] [Indexed: 01/15/2023] Open
Abstract
Different species are usually thought to have specific adaptations, which allow them to occupy different ecological niches. But recent neutral ecology theory suggests that species diversity can simply be the result of random sampling, due to finite population sizes and limited dispersal. Neutral models predict that species are not necessarily adapted to specific niches, but are functionally equivalent across a range of habitats. Here, we evaluate the ecology of Saccharomyces cerevisiae, one of the most important microbial species in human history. The artificial collection, concentration and fermentation of large volumes of fruit for alcohol production produce an environment in which S. cerevisiae thrives, and therefore it is assumed that fruit is the ecological niche that S. cerevisiae inhabits and has adapted to. We find very little direct evidence that S. cerevisiae is adapted to fruit, or indeed to any other specific niche. We propose instead a neutral nomad model for S. cerevisiae, which we believe should be used as the starting hypothesis in attempting to unravel the ecology of this important microbe. It is assumed that Saccharomyces cerevisiae is adapted to inhabit fruits; however, we find very little evidence for adaptation to any niche. Instead, we propose a neutral nomad model for S. cerevisiae.
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Affiliation(s)
- Matthew R Goddard
- The School of Biological Sciences, the University of Auckland, Auckland 1142, New Zealand The School of Life Sciences, the University of Lincoln, Lincoln LN6 7DL, UK
| | - Duncan Greig
- Max Planck Institute for Evolutionary Biology, Plön 24306, Germany Department of Genetics, Evolution, and Environment, University College London, London WC1E 6BT, UK
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