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Negoro H, Ishida H. Development of sake yeast breeding and analysis of genes related to its various phenotypes. FEMS Yeast Res 2022; 22:6825454. [PMID: 36370450 DOI: 10.1093/femsyr/foac057] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/21/2022] [Accepted: 11/10/2022] [Indexed: 11/13/2022] Open
Abstract
Sake is a traditional Japanese alcoholic beverage made from rice and water, fermented by the filamentous fungi Aspergillus oryzae and the yeast Saccharomyces cerevisiae. Yeast strains, also called sake yeasts, with high alcohol yield and the ability to produce desired flavor compounds in the sake, have been isolated from the environment for more than a century. Furthermore, numerous methods to breed sake yeasts without genetic modification have been developed. The objectives of breeding include increasing the efficiency of production, improving the aroma and taste, enhancing safety, imparting functional properties, and altering the appearance of sake. With the recent development of molecular biology, the suitable sake brewing characteristics in sake yeasts, and the causes of acquisition of additional phenotypes in bred yeasts have been elucidated genetically. This mini-review summarizes the history and lineage of sake yeasts, their genetic characteristics, the major breeding methods used, and molecular biological analysis of the acquired strains. The data in this review on the metabolic mechanisms of sake yeasts and their genetic profiles will enable the development of future strains with superior phenotypes.
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Affiliation(s)
- Hiroaki Negoro
- Research Institute, Gekkeikan Sake Co. Ltd., 101 Shimotoba-koyanagi-cho, Fushimi-ku, Kyoto 612-8385, Japan
| | - Hiroki Ishida
- Research Institute, Gekkeikan Sake Co. Ltd., 101 Shimotoba-koyanagi-cho, Fushimi-ku, Kyoto 612-8385, Japan
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2
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Kumari S, Kumar M, Gaur NA, Prasad R. Multiple roles of ABC transporters in yeast. Fungal Genet Biol 2021; 150:103550. [PMID: 33675986 DOI: 10.1016/j.fgb.2021.103550] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 01/29/2021] [Accepted: 02/25/2021] [Indexed: 12/20/2022]
Abstract
The ATP binding cassette (ABC) transporters, first discovered as high-affinity nutrient importers in bacteria, rose to prominence when their ability to confer multidrug resistance (MDR) to cancer cells was realized. The most characterized human permeability glycoprotein (P-gp) is a dominant exporter of anti-cancer drugs and its overexpression is directly linked to MDR. The overexpression of drug efflux pumps belonging to the ABC superfamily is also a frequent cause of resistance to antifungals. Fungi has a battery of ABC proteins, but in variable numbers and at different subcellular locations. These proteins perform many critical functions, from serving as gatekeepers for xenobiotic cleansing to translocating various structurally unrelated cargoes, including lipids, fatty acids, ions, peptides, sterols, metabolites and toxins. Their emerging additional roles in cellular physiology and virulence call for attention to analyze and re-examine their divergent functions in yeast. In brief, this review traces the history of ABC transporters in yeast and discusses their typical physiological functions that go beyond their well-known role as antifungal drug efflux pumps.
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Affiliation(s)
- Sonam Kumari
- Yeast Biofuel Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Mohit Kumar
- Yeast Biofuel Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India; Amity Institute of Integrative Science and Health, Amity Institute of Biotechnology, Amity University Gurgaon, 122413 Haryana, India
| | - Naseem A Gaur
- Yeast Biofuel Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India.
| | - Rajendra Prasad
- Amity Institute of Integrative Science and Health, Amity Institute of Biotechnology, Amity University Gurgaon, 122413 Haryana, India.
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Peltier E, Friedrich A, Schacherer J, Marullo P. Quantitative Trait Nucleotides Impacting the Technological Performances of Industrial Saccharomyces cerevisiae Strains. Front Genet 2019; 10:683. [PMID: 31396264 PMCID: PMC6664092 DOI: 10.3389/fgene.2019.00683] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 07/01/2019] [Indexed: 11/13/2022] Open
Abstract
The budding yeast Saccharomyces cerevisiae is certainly the prime industrial microorganism and is related to many biotechnological applications including food fermentations, biofuel production, green chemistry, and drug production. A noteworthy characteristic of this species is the existence of subgroups well adapted to specific processes with some individuals showing optimal technological traits. In the last 20 years, many studies have established a link between quantitative traits and single-nucleotide polymorphisms found in hundreds of genes. These natural variations constitute a pool of QTNs (quantitative trait nucleotides) that modulate yeast traits of economic interest for industry. By selecting a subset of genes functionally validated, a total of 284 QTNs were inventoried. Their distribution across pan and core genome and their frequency within the 1,011 Saccharomyces cerevisiae genomes were analyzed. We found that 150 of the 284 QTNs have a frequency lower than 5%, meaning that these variants would be undetectable by genome-wide association studies (GWAS). This analysis also suggests that most of the functional variants are private to a subpopulation, possibly due to their adaptive role to specific industrial environment. In this review, we provide a literature survey of their phenotypic impact and discuss the opportunities and the limits of their use for industrial strain selection.
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Affiliation(s)
- Emilien Peltier
- Department Sciences du vivant et de la sante, Université de Bordeaux, UR Œnologie EA 4577, Bordeaux, France
- Biolaffort, Bordeaux, France
| | - Anne Friedrich
- Department Micro-organismes, Génomes, Environnement, Université de Strasbourg, CNRS, GMGM UMR 7156, Strasbourg, France
| | - Joseph Schacherer
- Department Micro-organismes, Génomes, Environnement, Université de Strasbourg, CNRS, GMGM UMR 7156, Strasbourg, France
| | - Philippe Marullo
- Department Sciences du vivant et de la sante, Université de Bordeaux, UR Œnologie EA 4577, Bordeaux, France
- Biolaffort, Bordeaux, France
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Yang Y, Xia Y, Lin X, Wang G, Zhang H, Xiong Z, Yu H, Yu J, Ai L. Improvement of flavor profiles in Chinese rice wine by creating fermenting yeast with superior ethanol tolerance and fermentation activity. Food Res Int 2018; 108:83-92. [PMID: 29735105 DOI: 10.1016/j.foodres.2018.03.036] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 03/09/2018] [Accepted: 03/11/2018] [Indexed: 01/18/2023]
Abstract
Producing alcoholic beverages with novel flavor are desirable for winemakers. We created fermenting yeast with superior ethanol tolerance and fermentation activity to improve the flavor profiles of Chinese rice wine. Strategies of ethanol domestication, ultraviolet mutagenesis (UV) and protoplast fusion were conducted to create yeast hybrids with excellent oenological characteristic. The obtained diploid hybrid F23 showed a cell viability of 6.2% under 25% ethanol, whereas its diploid parental strains could not survive under 20% ethanol. During Chinese rice wine-making, compared to diploid parents, F23 produced 7.07%-12.44% higher yield of ethanol. Flavor analysis indicated that the total content of flavor compounds in F23 wine was 19.99-26.55% higher than that of parent wines. Specifically, F23 exhibited higher capacity in producing 2-phenylethanol, short-chain and long-chain fatty-acid ethyl-ester than diploid parents. Compared to diploid parents, F23 introduced more flavor contributors with odor activity values (OAVs) above one to Chinese rice wine, and those contributors were found with higher OAVs. Based on principal component analysis (PCA), the flavor characteristic of F23 wine was similar to each of parent wine. Additionally, sensory evaluation showed that F23 wine was highly assessed for its intensive levels in fruit-aroma, alcohol-aroma and mouthfeel. Hybrid F23 not only displayed superior flavor production and oenological performance in making Chinese rice wine, but also could act as potential "mixed-like" starter to enrich wine style and differentiation.
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Affiliation(s)
- Yijin Yang
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Yongjun Xia
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Xiangna Lin
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Guangqiang Wang
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Hui Zhang
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Zhiqiang Xiong
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, PR China
| | - Haiyan Yu
- School of Perfume and Aroma Technology, Shanghai Institute of Technology, Shanghai, 200235, PR China
| | - Jianshen Yu
- Shanghai Jinfeng Wine Co., Ltd., Shanghai, 200120, PR China
| | - Lianzhong Ai
- Shanghai Engineering Research Center of Food Microbiology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, PR China.
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Martí-Raga M, Peltier E, Mas A, Beltran G, Marullo P. Genetic Causes of Phenotypic Adaptation to the Second Fermentation of Sparkling Wines in Saccharomyces cerevisiae. G3 (BETHESDA, MD.) 2017; 7:399-412. [PMID: 27903630 PMCID: PMC5295589 DOI: 10.1534/g3.116.037283] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 11/14/2016] [Indexed: 01/12/2023]
Abstract
Hybridization is known to improve complex traits due to heterosis and phenotypic robustness. However, these phenomena have been rarely explained at the molecular level. Here, the genetic determinism of Saccharomyces cerevisiae fermentation performance was investigated using a QTL mapping approach on an F1-progeny population. Three main QTL were detected, with positive alleles coming from both parental strains. The heterosis effect found in the hybrid was partially explained by three loci showing pseudooverdominance and dominance effects. The molecular dissection of those QTL revealed that the adaptation to second fermentation is related to pH, lipid, or osmotic regulation. Our results suggest that the stressful conditions of second fermentation have driven the selection of rare genetic variants adapted to maintain yeast cell homeostasis and, in particular, to low pH conditions.
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Affiliation(s)
- Maria Martí-Raga
- Departament de Bioquímica i Biotecnologia, Facultat d'Enologia, Universitat Rovira i Virgili, 43007 Tarragona, Spain
- Unité de recherche OEnologie, EA 4577, ISVV, Université Bordeaux, 33882 Villenave d'Ornon, France
| | - Emilien Peltier
- Unité de recherche OEnologie, EA 4577, ISVV, Université Bordeaux, 33882 Villenave d'Ornon, France
- Biolaffort, 33100 Bordeaux, France
| | - Albert Mas
- Departament de Bioquímica i Biotecnologia, Facultat d'Enologia, Universitat Rovira i Virgili, 43007 Tarragona, Spain
| | - Gemma Beltran
- Departament de Bioquímica i Biotecnologia, Facultat d'Enologia, Universitat Rovira i Virgili, 43007 Tarragona, Spain
| | - Philippe Marullo
- Unité de recherche OEnologie, EA 4577, ISVV, Université Bordeaux, 33882 Villenave d'Ornon, France
- Biolaffort, 33100 Bordeaux, France
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Ma K, He M, You H, Pan L, Hu G, Cui Y, Maeda T. Enhanced fuel ethanol production from rice straw hydrolysate by an inhibitor-tolerant mutant strain of Scheffersomyces stipitis. RSC Adv 2017. [DOI: 10.1039/c7ra04049k] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A novel process for bioethanol production from lignocellulosic biomass using an inhibitor-tolerant mutant strain of Scheffersomyces stipitis and cell-recycling continuous fermentation.
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Affiliation(s)
- Kedong Ma
- College of Environmental and Chemical Engineering
- Dalian University
- Dalian 116622
- PR China
- Key Laboratory of Development and Application of Rural Renewable Energy
| | - Mingxiong He
- Key Laboratory of Development and Application of Rural Renewable Energy
- Ministry of Agriculture
- Biomass Energy Technology Research Centre
- Biogas Institute of Ministry of Agriculture
- Chengdu 610041
| | - Huiyan You
- College of Environmental and Chemical Engineering
- Dalian University
- Dalian 116622
- PR China
| | - Liwei Pan
- College of Environmental and Chemical Engineering
- Dalian University
- Dalian 116622
- PR China
| | - Guoquan Hu
- Key Laboratory of Development and Application of Rural Renewable Energy
- Ministry of Agriculture
- Biomass Energy Technology Research Centre
- Biogas Institute of Ministry of Agriculture
- Chengdu 610041
| | - Yubo Cui
- Department of Environmental Science and Technology
- Dalian Nationalities University
- Dalian 116600
- PR China
| | - Toshinari Maeda
- Department of Biological Functions Engineering
- Graduate School of Life Science and Systems Engineering
- Kyushu Institute of Technology
- Kitakyushu 808-0196
- Japan
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Ling H, Pratomo Juwono NK, Teo WS, Liu R, Leong SSJ, Chang MW. Engineering transcription factors to improve tolerance against alkane biofuels in Saccharomyces cerevisiae. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:231. [PMID: 26719765 PMCID: PMC4696261 DOI: 10.1186/s13068-015-0411-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 12/04/2015] [Indexed: 05/22/2023]
Abstract
BACKGROUND Biologically produced alkanes can be used as 'drop in' to existing transportation infrastructure as alkanes are important components of gasoline and jet fuels. Despite the reported microbial production of alkanes, the toxicity of alkanes to microbial hosts could pose a bottleneck for high productivity. In this study, we aimed to improve the tolerance of Saccharomyces cerevisiae, a model eukaryotic host of industrial significance, to alkane biofuels. RESULTS To increase alkane tolerance in S. cerevisiae, we sought to exploit the pleiotropic drug resistance (Pdr) transcription factors Pdr1p and Pdr3p, which are master regulators of genes with pleiotropic drug resistance elements (PDREs)-containing upstream sequences. Wild-type and site-mutated Pdr1p and Pdr3p were expressed in S. cerevisiae BY4741 pdr1Δ pdr3Δ (BYL13). The point mutations of PDR1 (F815S) and PDR3 (Y276H) in BYL13 resulted in the highest tolerance to C10 alkane, and the expression of wild-type PDR3 in BYL13 led to the highest tolerance to C11 alkane. To identify and verify the correlation between the Pdr transcription factors and tolerance improvement, we analyzed the expression patterns of genes regulated by the Pdr transcription factors in the most tolerant strains against C10 and C11 alkanes. Quantitative PCR results showed that the Pdr transcription factors differentially regulated genes associated with multi-drug resistance, stress responses, and membrane modifications, suggesting different extents of intracellular alkane levels, reactive oxygen species (ROS) production and membrane integrity. We further showed that (i) the expression of Pdr1mt1 + Pdr3mt reduced intracellular C10 alkane by 67 % and ROS by 53 %, and significantly alleviated membrane damage; and (ii) the expression of the Pdr3wt reduced intracellular C11 alkane by 72 % and ROS by 21 %. Alkane transport assays also revealed that the reduction of alkane accumulation was due to higher export (C10 and C11 alkanes) and lower import (C11 alkane). CONCLUSIONS We improved yeast's tolerance to alkane biofuels by modulating the expression of the wild-type and site-mutated Pdr1p and Pdr3p, and extensively identified the correlation between Pdr transcription factors and tolerance improvement by analyzing gene patterns, alkane transport, ROS, and membrane integrity. These findings provide valuable insights into manipulating transcription factors in yeast for improved alkane tolerance and productivity.
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Affiliation(s)
- Hua Ling
- />Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, 117597 Singapore, Singapore
- />NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), Life Sciences Institute, National University of Singapore, 28 Medical Drive, 117456 Singapore, Singapore
| | - Nina Kurniasih Pratomo Juwono
- />Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, 117597 Singapore, Singapore
- />NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), Life Sciences Institute, National University of Singapore, 28 Medical Drive, 117456 Singapore, Singapore
| | - Wei Suong Teo
- />Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, 117597 Singapore, Singapore
- />NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), Life Sciences Institute, National University of Singapore, 28 Medical Drive, 117456 Singapore, Singapore
| | - Ruirui Liu
- />Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, 117597 Singapore, Singapore
- />NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), Life Sciences Institute, National University of Singapore, 28 Medical Drive, 117456 Singapore, Singapore
| | - Susanna Su Jan Leong
- />Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, 117597 Singapore, Singapore
- />NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), Life Sciences Institute, National University of Singapore, 28 Medical Drive, 117456 Singapore, Singapore
- />Singapore Institute of Technology, 10 Dover Drive, 138683 Singapore, Singapore
| | - Matthew Wook Chang
- />Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, 117597 Singapore, Singapore
- />NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), Life Sciences Institute, National University of Singapore, 28 Medical Drive, 117456 Singapore, Singapore
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Kitagaki H, Kitamoto K. Breeding Research on Sake Yeasts in Japan: History, Recent Technological Advances, and Future Perspectives. Annu Rev Food Sci Technol 2013; 4:215-35. [DOI: 10.1146/annurev-food-030212-182545] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Hiroshi Kitagaki
- Department of Environmental Sciences, Faculty of Agriculture, Saga University, Saga 840-8502, Japan;
- Department of Biochemistry and Applied Biosciences, United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima 890-8580, Japan
| | - Katsuhiko Kitamoto
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-8657, Japan;
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Functional roles of YPT31 and YPT32 in clotrimazole resistance of Saccharomyces cerevisiae through effects on vacuoles and ATP-binding cassette transporter(s). J Biosci Bioeng 2013; 115:4-11. [DOI: 10.1016/j.jbiosc.2012.08.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 08/14/2012] [Accepted: 08/16/2012] [Indexed: 12/29/2022]
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Sanglard D, Coste A, Ferrari S. Antifungal drug resistance mechanisms in fungal pathogens from the perspective of transcriptional gene regulation. FEMS Yeast Res 2009; 9:1029-50. [PMID: 19799636 DOI: 10.1111/j.1567-1364.2009.00578.x] [Citation(s) in RCA: 179] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Fungi are primitive eukaryotes and have adapted to a variety of niches during evolution. Some fungal species may interact with other life forms (plants, insects, mammals), but are considered as pathogens when they cause mild to severe diseases. Chemical control strategies have emerged with the development of several drugs with antifungal activity against pathogenic fungi. Antifungal agents have demonstrated their efficacy by improving patient health in medicine. However, fungi have counteracted antifungal agents in several cases by developing resistance mechanisms. These mechanisms rely on drug resistance genes including multidrug transporters and drug targets. Their regulation is crucial for the development of antifungal drug resistance and therefore transcriptional factors critical for their regulation are being characterized. Recent genome-wide studies have revealed complex regulatory circuits involving these genetic and transcriptional regulators. Here, we review the current understanding of the transcriptional regulation of drug resistance genes from several fungal pathogens including Candida and Aspergillus species.
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Affiliation(s)
- Dominique Sanglard
- Institute of Microbiology, University of Lausanne and University Hospital Center, 1011 Lausanne, Switzerland.
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Coste A, Selmecki A, Forche A, Diogo D, Bougnoux ME, d'Enfert C, Berman J, Sanglard D. Genotypic evolution of azole resistance mechanisms in sequential Candida albicans isolates. EUKARYOTIC CELL 2007; 6:1889-904. [PMID: 17693596 PMCID: PMC2043391 DOI: 10.1128/ec.00151-07] [Citation(s) in RCA: 218] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
TAC1 (for transcriptional activator of CDR genes) is critical for the upregulation of the ABC transporters CDR1 and CDR2, which mediate azole resistance in Candida albicans. While a wild-type TAC1 allele drives high expression of CDR1/2 in response to inducers, we showed previously that TAC1 can be hyperactive by a gain-of-function (GOF) point mutation responsible for constitutive high expression of CDR1/2. High azole resistance levels are achieved when C. albicans carries hyperactive alleles only as a consequence of loss of heterozygosity (LOH) at the TAC1 locus on chromosome 5 (Chr 5), which is linked to the mating-type-like (MTL) locus. Both are located on the Chr 5 left arm along with ERG11 (target of azoles). In this work, five groups of related isolates containing azole-susceptible and -resistant strains were analyzed for the TAC1 and ERG11 alleles and for Chr 5 alterations. While recovered ERG11 alleles contained known mutations, 17 new TAC1 alleles were isolated, including 7 hyperactive alleles with five separate new GOF mutations. Single-nucleotide-polymorphism analysis of Chr 5 revealed that azole-resistant strains acquired TAC1 hyperactive alleles and, in most cases, ERG11 mutant alleles by LOH events not systematically including the MTL locus. TAC1 LOH resulted from mitotic recombination of the left arm of Chr 5, gene conversion within the TAC1 locus, or the loss and reduplication of the entire Chr 5. In one case, two independent TAC1 hyperactive alleles were acquired. Comparative genome hybridization and karyotype analysis revealed the presence of isochromosome 5L [i(5L)] in two azole-resistant strains. i(5L) leads to increased copy numbers of azole resistance genes present on the left arm of Chr 5, among them TAC1 and ERG11. Our work shows that azole resistance was due not only to the presence of specific mutations in azole resistance genes (at least ERG11 and TAC1) but also to their increase in copy number by LOH and to the addition of extra Chr 5 copies. With the combination of these different modifications, sophisticated genotypes were obtained. The development of azole resistance in C. albicans is therefore a powerful instrument for generating genetic diversity.
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Affiliation(s)
- Alix Coste
- Institute of Microbiology, University of Lausanne and University Hospital Center, Rue du Bugnon 48, CH-1011, Lausanne, Switzerland
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Dunn B, Levine RP, Sherlock G. Microarray karyotyping of commercial wine yeast strains reveals shared, as well as unique, genomic signatures. BMC Genomics 2005; 6:53. [PMID: 15833139 PMCID: PMC1097725 DOI: 10.1186/1471-2164-6-53] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Accepted: 04/16/2005] [Indexed: 11/10/2022] Open
Abstract
Background Genetic differences between yeast strains used in wine-making may account for some of the variation seen in their fermentation properties and may also produce differing sensory characteristics in the final wine product itself. To investigate this, we have determined genomic differences among several Saccharomyces cerevisiae wine strains by using a "microarray karyotyping" (also known as "array-CGH" or "aCGH") technique. Results We have studied four commonly used commercial wine yeast strains, assaying three independent isolates from each strain. All four wine strains showed common differences with respect to the laboratory S. cerevisiae strain S288C, some of which may be specific to commercial wine yeasts. We observed very little intra-strain variation; i.e., the genomic karyotypes of different commercial isolates of the same strain looked very similar, although an exception to this was seen among the Montrachet isolates. A moderate amount of inter-strain genomic variation between the four wine strains was observed, mostly in the form of depletions or amplifications of single genes; these differences allowed unique identification of each strain. Many of the inter-strain differences appear to be in transporter genes, especially hexose transporters (HXT genes), metal ion sensors/transporters (CUP1, ZRT1, ENA genes), members of the major facilitator superfamily, and in genes involved in drug response (PDR3, SNQ1, QDR1, RDS1, AYT1, YAR068W). We therefore used halo assays to investigate the response of these strains to three different fungicidal drugs (cycloheximide, clotrimazole, sulfomethuron methyl). Strains with fewer copies of the CUP1 loci showed hypersensitivity to sulfomethuron methyl. Conclusion Microarray karyotyping is a useful tool for analyzing the genome structures of wine yeasts. Despite only small to moderate variations in gene copy numbers between different wine yeast strains and within different isolates of a given strain, there was enough variation to allow unique identification of strains; additionally, some of the variation correlated with drug sensitivity. The relatively small number of differences seen by microarray karyotyping between the strains suggests that the differences in fermentative and organoleptic properties ascribed to these different strains may arise from a small number of genetic changes, making it possible to test whether the observed differences do indeed confer different sensory properties in the finished wine.
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Affiliation(s)
- Barbara Dunn
- Dept. of Genetics, Stanford University Medical Ctr., Stanford, CA 94305-5120, USA
| | - R Paul Levine
- Dept. of Biological Sciences, Stanford University, Stanford, CA 94305-5020, USA
| | - Gavin Sherlock
- Dept. of Genetics, Stanford University Medical Ctr., Stanford, CA 94305-5120, USA
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Current awareness on yeast. Yeast 2002; 19:995-1002. [PMID: 12125056 DOI: 10.1002/yea.827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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