Most information on yeasts derives from experiments with the conventional yeasts Saccaromyces cerevisiae and Schizossaccharomyces pombe, the complete nuclear and mitochondrial genome of which has also been sequenced. For all other non-conventional yeasts, investigations are in progress and the rapid development of molecular techniques has allowed an insight also into a variety of non-conventional yeasts. In this bench manual, over 70 practical protocols using 15 different non-conventional yeast species and in addition several protocols of general use are described in detail. All of these experiments on the genetics, biochemistry and biotechnology of yeasts have been contributed by renowned laboratories and have been reproduced many times. The reliable protocols are thus ideally suited also for undergraduate and graduate practical courses.

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.

Most information on yeasts derives from experiments with the conventional yeasts Saccaromyces cerevisiae and Schizossaccharomyces pombe, the complete nuclear and mitochondrial genome of which has also been sequenced. For all other non-conventional yeasts, investigations are in progress and the rapid development of molecular techniques has allowed an insight also into a variety of non-conventional yeasts. In this bench manual, over 70 practical protocols using 15 different non-conventional yeast species and in addition several protocols of general use are described in detail. All of these experiments on the genetics, biochemistry and biotechnology of yeasts have been contributed by renowned laboratories and have been reproduced many times. The reliable protocols are thus ideally suited also for undergraduate and graduate practical courses.

I belie ve that the book would provide an overview of the recent developments in the domain of yeast research with some new ideas, which could serve as an inspiration and challenge for researchers in this field. Ne w Delhi Prof. Asis Datta Dec. 24, 2007 F ormer Vice-chancellor, JNU Director, NCPGR (New Delhi) Pr eface Yeasts are eukaryotic unicellular microfungi that are widely distributed in the natural environments. Although yeasts are not as ubiquitous as bacteria in the na- ral environments, they have been isolated from terrestrial, aquatic and atmospheric environments. Yeast communities have been found in association with plants, a- mals and insects. Several species of yeasts have also been isolated from specialized or extreme environments like those with low water potential (e. g. high sugar/salt concentrations), low temperature (e. g. yeasts isolated from Antarctica), and low oxygen availability (e. g. intestinal tracts of animals). Around 1500 species of yeasts belonging to over 100 genera have been described so far. It is estimated that only 1% of the extant yeasts on earth have been described till date. Therefore, global efforts are underway to recover new yeast species from a variety of normal and extreme environments. Yeasts play an important role in food chains, and carbon, nitrogen and sulphur cycles. Yeasts can be genetically manipulated by hybridization, mutation, rare m- ing, cytoduction, spheroplast fusion, single chromosomal transfer and transfor- tion using recombinant technology. Yeasts (e. g.

This book brings together and updates the latest information on the diversity of yeasts, their molecular features and their applications in the welfare of mankind. Yeasts are eukaryotic microfungi widely found in natural environments, including those with extreme conditions such as low temperatures, low oxygen levels and low water availability. To date, approximately 2,000 of the estimated 30,000 to 45,000 species of yeast on Earth, belonging to around 200 genera have been described. Although there are a few that are opportunistic human and animal pathogens, the vast majority of yeasts are beneficial, playing an important role in the food chain and in the carbon, nitrogen and sulphur cycles. In addition, yeasts such as Saccharomyces cerevisiae, Hansenula polymorpha and Pichia pastoris are used in expressing foreign genes to produce proteins of pharmaceutical interest. A landmark in biotechnology was reached in 1996 with the completion of sequencing of the entire S. cerevisiae genome, and it has now become a central player in the development of an entirely new approach to biological research and synthetic biology. The sequencing of genomes of several yeasts including Schizosaccharomyces pombe, Candida albicans and Cryptococcus neofromans has also recently been completed. candida albicans="" and="" p/pp

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.