Functional and Comparative Genomics of Saccharomyces and non-Saccharomyces Yeasts: Potential for Industrial and Food Biotechnology

Functional and Comparative Genomics of Saccharomyces and non-Saccharomyces Yeasts: Potential for Industrial and Food Biotechnology PDF Author: Isabel Sá-Correia
Publisher: Frontiers Media SA
ISBN: 2889635228
Category :
Languages : en
Pages : 255

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Book Description
Since 1996, when the first Saccharomyces cerevisiae genome sequence was released, a wealth of genomic data has been made available for numerous S. cerevisiae strains, its close relatives, and non-conventional yeast species isolates of diverse origins. Several annotated genomes of interspecific hybrids, both within the Saccharomyces clade and outside, are now also available. This genomic information, together with functional genomics and genome engineering tools, is providing a holistic assessment of the complex cellular responses to environmental challenges, elucidating the processes underlying evolution, speciation, hybridization, domestication, and uncovering crucial aspects of yeasts´ physiological genomics to guide their biotechnological exploitation. S. cerevisiae has been used for millennia in the production of food and beverages and research over the last century and a half has generated a great deal of knowledge of this species. Despite all this, S. cerevisiae is not the best for all uses and many non-conventional yeast species have highly desirable traits that S. cerevisiae does not have. These include tolerance to different stresses (e.g. acetic acid tolerance in Zygosaccharomyces bailii, osmotolerance in Z. rouxii, and thermotolerance in Kluyveromyces marxianus and Ogataea (Hansenula) polymorpha), the capacity of assimilation of diverse carbon sources (e.g. high native capacity to metabolyze xylose and potential for the valorization of agroforest residues by Scheffersomyces (Pichia) stipites), as well as, high protein secretion, fermentation efficiency and production of desirable flavors, capacity to favor respiration over fermentation, high lipid biosynthesis and accumulation, and efficient production of chemicals other than ethanol amongst many. Several non-Saccharomyces species have already been developed as eukaryotic hosts and cell factories. Others are highly relevant as food spoilers or for desirable flavor producers. Therefore, non-conventional yeasts are now attracting increasing attention with their diversity and complexity being tackled by basic research for biotechnological applications. The interest in the exploitation of non-conventional yeasts is very high and a number of tools, such as cloning vectors, promoters, terminators, and efficient genome editing tools, have been developed to facilitate their genetic engineering. Functional and Comparative Genomics of non-conventional yeasts is elucidating the evolution of genome functions and metabolic and ecological diversity, relating their physiology to genomic features and opening the door to the application of metabolic engineering and synthetic biology to yeasts of biotechnological potential. We are entering the era of the non-conventional yeasts, increasing the exploitation of yeast biodiversity and metabolic capabilities in science and industry. In this collection the industrial properties of S. cerevisiae, in particular uses, are explored along with its closely related species and interspecific hybrids. This is followed by comparisons between S. cerevisiae and non-conventional yeasts in specific applications and then the properties of various non-conventional yeasts and their hybrids.

Functional and Comparative Genomics of Saccharomyces and non-Saccharomyces Yeasts: Potential for Industrial and Food Biotechnology

Functional and Comparative Genomics of Saccharomyces and non-Saccharomyces Yeasts: Potential for Industrial and Food Biotechnology PDF Author: Isabel Sá-Correia
Publisher: Frontiers Media SA
ISBN: 2889635228
Category :
Languages : en
Pages : 255

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Book Description
Since 1996, when the first Saccharomyces cerevisiae genome sequence was released, a wealth of genomic data has been made available for numerous S. cerevisiae strains, its close relatives, and non-conventional yeast species isolates of diverse origins. Several annotated genomes of interspecific hybrids, both within the Saccharomyces clade and outside, are now also available. This genomic information, together with functional genomics and genome engineering tools, is providing a holistic assessment of the complex cellular responses to environmental challenges, elucidating the processes underlying evolution, speciation, hybridization, domestication, and uncovering crucial aspects of yeasts´ physiological genomics to guide their biotechnological exploitation. S. cerevisiae has been used for millennia in the production of food and beverages and research over the last century and a half has generated a great deal of knowledge of this species. Despite all this, S. cerevisiae is not the best for all uses and many non-conventional yeast species have highly desirable traits that S. cerevisiae does not have. These include tolerance to different stresses (e.g. acetic acid tolerance in Zygosaccharomyces bailii, osmotolerance in Z. rouxii, and thermotolerance in Kluyveromyces marxianus and Ogataea (Hansenula) polymorpha), the capacity of assimilation of diverse carbon sources (e.g. high native capacity to metabolyze xylose and potential for the valorization of agroforest residues by Scheffersomyces (Pichia) stipites), as well as, high protein secretion, fermentation efficiency and production of desirable flavors, capacity to favor respiration over fermentation, high lipid biosynthesis and accumulation, and efficient production of chemicals other than ethanol amongst many. Several non-Saccharomyces species have already been developed as eukaryotic hosts and cell factories. Others are highly relevant as food spoilers or for desirable flavor producers. Therefore, non-conventional yeasts are now attracting increasing attention with their diversity and complexity being tackled by basic research for biotechnological applications. The interest in the exploitation of non-conventional yeasts is very high and a number of tools, such as cloning vectors, promoters, terminators, and efficient genome editing tools, have been developed to facilitate their genetic engineering. Functional and Comparative Genomics of non-conventional yeasts is elucidating the evolution of genome functions and metabolic and ecological diversity, relating their physiology to genomic features and opening the door to the application of metabolic engineering and synthetic biology to yeasts of biotechnological potential. We are entering the era of the non-conventional yeasts, increasing the exploitation of yeast biodiversity and metabolic capabilities in science and industry. In this collection the industrial properties of S. cerevisiae, in particular uses, are explored along with its closely related species and interspecific hybrids. This is followed by comparisons between S. cerevisiae and non-conventional yeasts in specific applications and then the properties of various non-conventional yeasts and their hybrids.

High Throughput Methods for Functional Genomics in Saccharomyces Cerevisiae

High Throughput Methods for Functional Genomics in Saccharomyces Cerevisiae PDF Author: Sarah Elizabeth Pierce
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
The Saccharomyces cerevisiae deletion collection has revolutionized yeast genetics by allowing genome-wide deletion screens to be performed in pooled cultures. The inclusion of unique, 20-bp DNA sequences known as "tags" or "barcodes" in each strain allows all ~6000 yeast deletion mutants to be analyzed in a single culture by using a microarray to detect changes in tag abundance. Here we discuss improvements and extensions made to the pooled-yeast-deletion assay. This includes a redesign of the barcode array that is used for detecting the tags included in the deletion collection. Our analysis of this barcode array examines whether it is better to use available microarray surface area on a single feature for each probe, or to instead include multiple smaller features. It also covers aspects of data analysis such as the correction of hybridization defects and array saturation, tag-sequence repairs, and estimation of background hybridization. In addition to these microarray changes, we also examine the impact of experimental design on the quality of pooled growth data. Each step in both the experimental protocol and the data-analysis pipeline is examined for possible improvement. Finally, we discuss preliminary experiments testing the application of pooled fitness profiling to the study of epistasis. Data are shown that demonstrate the feasibility of a pooled-double-mutant fitness assay that is compatible with existing barcode array technology. This assay has the potential to become a valuable functional-genomics tool that may provide an improved understanding of pathway relationships in yeast.

Using Comparative Genomics in Saccharomyces Cerevisiae to Engineer Lignocellulosic Hydrolysate Tolerance

Using Comparative Genomics in Saccharomyces Cerevisiae to Engineer Lignocellulosic Hydrolysate Tolerance PDF Author: Maria Isabel Sardi
Publisher:
ISBN:
Category :
Languages : en
Pages : 372

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Book Description
The increased interest in alternative fuels is driving the development of more efficient and economical production of biofuels. This requires the use of non-food based plant biomass to produce advanced biofuels such as butanol and isobutanol. A major challenge of implementing this new energy source is that the chemically treated plant material, known as lignocellulosic hydrolysate, contains a variety of toxic compounds that affect fermenting microbes, decreasing the economic efficiency of lignocellulosic biofuel production. In addition, butanol and isobutanol are toxic even at small concentrations, making end product toxicity a significant limiting factor. In this thesis, we report the use of multiple genomic strategies to identify mechanisms of toxicity and tolerance that can be then use to engineer tolerance into industrially relevant microbes. First, by comparing and contrasting the transcriptional responses of tolerant and sensitive Saccharomyces cerevisiae strains exposed to these stresses, we identified primary toxin targets and their effects on cellular physiology. Second, we explored genetic differences among strains to performed a genome wide association study that identified genetic variants correlated with tolerance to plant hydrolysate. By applying multiple genomic methods and integrating the results, we identified strategies for improving tolerance to the stresses found in the production of advanced biofuels from plant hydrolysate and identified large effects of genetic background on phenotypic outcome, which highlights challenges in predicting the most beneficial engineering strategies for each specific strain.

Studies on the Evolution of Silencing in Budding Yeasts Using Comparative Genomics

Studies on the Evolution of Silencing in Budding Yeasts Using Comparative Genomics PDF Author: Aisha Ellahi
Publisher:
ISBN:
Category :
Languages : en
Pages : 127

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Book Description
Regional promoter-independent gene silencing is critical in the establishment of cellular identity in Saccharomyces. Domains of transcriptionally silent regions in the genome are associated with certain heritable modifications made to chromatin, such as histone hypoacetylation and methylation. In Saccharomyces cerevisiae, this type of gene repression occurs through the activity of the four Silent Information Regulator, or SIR genes (SIR1-4). From an evolutionary perspective, the SIR genes are unique: except for SIR2, all are specific to budding yeasts. Many other organisms, from Schizosaccharomyces pombe to human, utilize the RNA interference (RNAi) pathway, whereas most budding yeasts lack this pathway entirely. Interestingly, SIR1, SIR3, and SIR4 are also rapidly evolving among Saccharomyces yeasts, providing a model by which to examine the essential principles governing successful silencing across various species and the relationship between rapid sequence evolution and evolution of function. To examine the relationship between gene duplication, extreme sequence divergence, and functional evolution, I studied the SIR1 gene in S. cerevisiae and its most ancestral paralog, KOS3, in the pre-whole-genome-duplication budding yeast, Torulaspora delbrueckii. T. delbrueckii also possesses genes for RNAi, AGO1 and DCR1, allowing us the possibility of exploring how the evolutionary divergence of RNAi and SIR silencing occurred. In the process, I developed genetic tools for T. delbrueckii. To fully characterize SIR1 function in S. cerevisiae and SIR gene function in T. delbrueckii, I utilized chromatin immunoprecipitation followed by deep-sequencing (ChIP-Seq) of tagged Sir proteins in both species. This strategy allowed for the discovery of potential novel functions, as well, revealing functions that may have been gained or lost throughout SIR1's evolution. To identify loci that were directly repressed by Sir proteins, I also generated whole-transcriptome data by performing mRNA-Seq on wild-type and sir mutants in both species. Collectively, these data revealed that though SIR1 in both species is still involved in silencing, its role in that process has dramatically shifted. Previous data suggested that SIR1 is primarily associated with the establishment or nucleation phase of silencing and not involved in telomeric silencing. The Sir1 ChIP data in S. cerevisiae corroborated this assessment. In T. delbrueckii, however, KOS3 was essential for silencing, and was also found at telomeres. Thus, Sir1 in its early evolution had a more essential role in silencing; this role may have changed due to the duplication and diversification of the other Sir complex members. This diversification may be contributing to the continual change in interactions between Sir1 and other Sir complex members across budding yeasts, leading to different mutant phenotypes in each species. Assays of silencer function in T. delbrueckii answered critical questions about when in the phylogeny important shifts in transcription factor binding sites took place. My work showed that the arrival of the Rap1, ORC, and Abf1 binding sites in the silencers of budding yeasts took place prior to the whole-genome duplication event. Analysis of silencer structure also revealed the diversity of chromatin architecture in budding yeasts: S. cerevisiae silent mating type loci have two silencers on either side of each locus, whereas in T. delbrueckii, there appears to be a single silencer on one side of each mating type locus. Transcriptome analysis of RNAi mutants revealed that this pathway in T. delbrueckii does not function in heterochromatic gene silencing, suggesting that this pathway has already been repurposed for some other biological process. The examination of whole-transcriptome data in S. cerevisiae in conjunction with the enrichment patterns of the Sir proteins at telomeres allowed us to evaluate widely accepted models regarding the molecular architecture of heterochromatin and expression at S. cerevisiae telomeres. I established that repression of gene expression at native telomeres is not as widespread as previously thought, and that many genes in proximity to regions of Sir protein enrichment were, in fact, expressed just as equally in wild type as they were in sir mutant genetic backgrounds. However, twenty-one genes were convincingly repressed by Sir proteins, highlighting the complex and individual nature of native telomeres and subtelomeric genes. The sensitivity of RNA-Seq also uncovered a previously under-appreciated class of haploid-regulated genes: genes that were not fully repressed or de-repressed in the diploid a/[alpha]-cell type, but rather weakly repressed or de-repressed. Thus, my work has expanded the set of known a/[alpha]-regulated genes in S. cerevisiae. In conclusion, this dissertation has broadened our understanding of the functional constraints dictating silencing gene evolution across species that diverged prior to and after the whole-genome-duplication event. My data speaks to the actual chromatin architecture and expression state of native S. cerevisiae telomeres, leading to the refinement of existing models and an appreciation for how heterogeneous these regions of the genome can be.

Yeasts in Food and Beverages

Yeasts in Food and Beverages PDF Author: Amparo Querol
Publisher: Springer Science & Business Media
ISBN: 3540283986
Category : Science
Languages : en
Pages : 457

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Book Description
As a group of microorganisms, yeasts have an enormous impact on food and bev- age production. Scientific and technological understanding of their roles in this p- duction began to emerge in the mid-1800s, starting with the pioneering studies of Pasteur in France and Hansen in Denmark on the microbiology of beer and wine fermentations. Since that time, researchers throughout the world have been engaged in a fascinating journey of discovery and development – learning about the great diversity of food and beverage commodities that are produced or impacted by yeast activity, about the diversity of yeast species associated with these activities, and about the diversity of biochemical, physiological and molecular mechanisms that underpin the many roles of yeasts in food and beverage production. Many excellent books have now been published on yeasts in food and beverage production, and it is reasonable to ask the question – why another book? There are two different approaches to describe and understand the role of yeasts in food and beverage production. One approach is to focus on the commodity and the technology of its processing (e. g. wine fermentation, fermentation of bakery products), and this is the direction that most books on food and beverage yeasts have taken, to date. A second approach is to focus on the yeasts, themselves, and their bi- ogy in the context of food and beverage habitats.

Non-conventional Yeasts: from Basic Research to Application

Non-conventional Yeasts: from Basic Research to Application PDF Author: Andriy Sibirny
Publisher: Springer
ISBN: 303021110X
Category : Science
Languages : en
Pages : 568

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Book Description
This volume scopes several aspects of non-conventional yeast research prepared by the leading specialists in the field. An introduction on taxonomy and systematics enhances the reader’s knowledge on yeasts beyond established ones such as Saccharomyces cerevisiae. Biotechnological approaches that involve fungal utilization of unusual substrates, production of biofuels and useful chemicals as citric acid, glutathione or erythritol are discussed. Further, strategies for metabolic engineering based on knowledge on regulation of gene expression as well as sensing and signaling pathways are presented. The book targets researchers and advanced students working in Microbiology, Microbial Biotechnology and Biochemistry.

Enzymes in Food Biotechnology

Enzymes in Food Biotechnology PDF Author: Mohammed Kuddus
Publisher: Academic Press
ISBN: 0128132817
Category : Technology & Engineering
Languages : en
Pages : 912

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Book Description
Enzymes in Food Biotechnology: Production, Applications, and Future Prospects presents a comprehensive review of enzyme research and the potential impact of enzymes on the food sector. This valuable reference brings together novel sources and technologies regarding enzymes in food production, food processing, food preservation, food engineering and food biotechnology that are useful for researchers, professionals and students. Discussions include the process of immobilization, thermal and operational stability, increased product specificity and specific activity, enzyme engineering, implementation of high-throughput techniques, screening to relatively unexplored environments, and the development of more efficient enzymes. Explores recent scientific research to innovate novel, global ideas for new foods and enzyme engineering Provides fundamental and advanced information on enzyme research for use in food biotechnology, including microbial, plant and animal enzymes Includes recent cutting-edge research on the pharmaceutical uses of enzymes in the food industry

White Wine Technology

White Wine Technology PDF Author: Antonio Morata
Publisher: Academic Press
ISBN: 0128236558
Category : Technology & Engineering
Languages : en
Pages : 431

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Book Description
White Wine Technology addresses the challenges surrounding white wine production. The book explores emerging trends in modern enology, including molecular tools for wine quality and analysis of modern approaches to maceration extraction, alternative microorganisms for alcoholic fermentation, and malolactic fermentation. The book focuses on the technology and biotechnology of white wines, providing a quick reference of novel ways to increase and improve overall wine production and innovation. Its reviews of recent studies and technological advancements to improve grape maturity and production and ways to control PH level make this book essential to wine producers, researchers, practitioners, technologists and students. Covers trends in in both traditional and modern enology technologies, including extraction, processing, stabilization and ageing technologies Examines the potential impacts of climate change on wine quality Provides an overview of biotechnologies to improve wine freshness in warm areas and to manage maturity in cold climates Includes detailed information on hot topics such as the use of GMOs in wine production, spoilage bacteria, the management of oxidation, and the production of dealcoholized wines

From Traditional to Modern: Progress of Molds and Yeasts in Fermented-food Production, Volume II

From Traditional to Modern: Progress of Molds and Yeasts in Fermented-food Production, Volume II PDF Author: Wanping Chen
Publisher: Frontiers Media SA
ISBN: 2832508162
Category : Science
Languages : en
Pages : 148

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Book Description


Microbiota of Grapes: Positive and Negative Role on Wine Quality

Microbiota of Grapes: Positive and Negative Role on Wine Quality PDF Author: Giuseppe Spano
Publisher: Frontiers Media SA
ISBN: 2889451216
Category :
Languages : en
Pages : 233

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Book Description
During spontaneous food/beverage fermentations, the microbiota associated with the raw material has a considerable importance: this microbial consortium evolves in reason of the nutrient content and of the physical, chemical, and biological determinants present in the food matrix, shaping fermentation dynamics with significant impacts on the ‘qualities’ of final productions. The selection from the indigenous micro-biodiversity of ‘virtuous’ ecotypes that coupled pro-technological and biotechnological aptitudes provide the basis for the formulation of ‘tailored’ starter cultures. In the fermenting food and beverage arena, the wine sector is generally characterized by the generation of a high added value. Together with a pronounced seasonality, this feature strongly contributes to the selection of a large group of starter cultures. In the last years, several studies contributed to describe the complexity of grapevine-associated microbiota using both culture-dependent and culture-independent approaches. The grape-associated microbial communities continuously change during the wine-making process, with different dominances that correspond to the main biotechnological steps that take place in wine. In order to simplify, following a time trend, four major dominances can be mainly considered: non-Saccharomyces, Saccharomyces, lactic acid bacteria (LAB), and spoilage microbes. The first two dominances come in succession during the alcoholic fermentation: the impact of Saccharomyces (that are responsible of key enological step of ethanol production) can be complemented/integrated by the contributions of compatible non-Saccharomyces strains. Lactic acid bacteria constitute the malolactic consortium responsible of malolactic fermentation, a microbial bioconversion often desired in wine (especially in red wine production). Finally, the fourth dominance, the undesired microbiota, represents a panel of microorganisms that, coupling spoilage potential to the resistance to the harsh conditions typical of wine environment, can cause important economic losses. In each of these four dominances a complex microbial biodiversity has been described. The studies on the enological significance of the micro-biodiversity connected with each of the four dominances highlighted the presence of a dichotomy: in each consortia there are species/strains that, in reason of their metabolisms, are able to improve wine ‘qualities’ (resource of interest in starter cultures design), and species/strains that with their metabolism are responsible of depreciation of wine. Articles describing new oenological impacts of yeasts and bacteria belonging to the four main categories above mentioned (non-Saccharomyces, Saccharomycetes, lactic acid bacteria, and spoilage microbes) are welcome. Moreover, in this Research Topic, we encourage mini-review submissions on topics of immediate interest in wine microbiology that link microbial biodiversity with positive/negative effects in wine.