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Ou H, Zhang P, Wang X, Lin M, Li Y, Wang G. Gaining insights into the responses of individual yeast cells to ethanol fermentation using Raman tweezers and chemometrics. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 319:124584. [PMID: 38838600 DOI: 10.1016/j.saa.2024.124584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 05/18/2024] [Accepted: 05/30/2024] [Indexed: 06/07/2024]
Abstract
Saccharomyces cerevisiae is the most common microbe used for the industrial production of bioethanol, and it encounters various stresses that inhibit cell growth and metabolism during fermentation. However, little is currently known about the physiological changes that occur in individual yeast cells during ethanol fermentation. Therefore, in this work, Raman spectroscopy and chemometric techniques were employed to monitor the metabolic changes of individual yeast cells at distinct stages during high gravity ethanol fermentation. Raman tweezers was used to acquire the Raman spectra of individual yeast cells. Multivariate curve resolution-alternating least squares (MCR-ALS) and principal component analysis were employed to analyze the Raman spectra dataset. MCR-ALS extracted the spectra of proteins, phospholipids, and triacylglycerols and their relative contents in individual cells. Changes in intracellular biomolecules showed that yeast cells undergo three distinct physiological stages during fermentation. In addition, heterogeneity among yeast cells significantly increased in the late fermentation period, and different yeast cells may respond to ethanol stress via different mechanisms. Our findings suggest that the combination of Raman tweezers and chemometrics approaches allows for characterizing the dynamics of molecular components within individual cells. This approach can serve as a valuable tool in investigating the resistance mechanism and metabolic heterogeneity of yeast cells during ethanol fermentation.
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Affiliation(s)
- Haisheng Ou
- Institute of Eco-Environmental Research, Guangxi Academy of Sciences, 98 Daling Road, Nanning, Guangxi 530007, China; College of Physics Science and Technology, Guangxi Normal University, 15 Yucai Road, Guilin, Guangxi 541004, China
| | - Pengfei Zhang
- School of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Xiaochun Wang
- Institute of Eco-Environmental Research, Guangxi Academy of Sciences, 98 Daling Road, Nanning, Guangxi 530007, China
| | - Manman Lin
- School of Electronic and Information Engineering, Zhongyuan University of Technology, Zhengzhou 450007, China
| | - Yuanpeng Li
- College of Physics Science and Technology, Guangxi Normal University, 15 Yucai Road, Guilin, Guangxi 541004, China
| | - Guiwen Wang
- Institute of Eco-Environmental Research, Guangxi Academy of Sciences, 98 Daling Road, Nanning, Guangxi 530007, China.
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2
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Dukic B, Ruppert Z, Tóth ME, Hunya Á, Czibula Á, Bíró P, Tiszlavicz Á, Péter M, Balogh G, Erdélyi M, Timinszky G, Vígh L, Gombos I, Török Z. Mild Hyperthermia-Induced Thermogenesis in the Endoplasmic Reticulum Defines Stress Response Mechanisms. Cells 2024; 13:1141. [PMID: 38994992 PMCID: PMC11240596 DOI: 10.3390/cells13131141] [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: 06/05/2024] [Revised: 06/24/2024] [Accepted: 06/27/2024] [Indexed: 07/13/2024] Open
Abstract
Previous studies reported that a mild, non-protein-denaturing, fever-like temperature increase induced the unfolded protein response (UPR) in mammalian cells. Our dSTORM super-resolution microscopy experiments revealed that the master regulator of the UPR, the IRE1 (inositol-requiring enzyme 1) protein, is clustered as a result of UPR activation in a human osteosarcoma cell line (U2OS) upon mild heat stress. Using ER thermo yellow, a temperature-sensitive fluorescent probe targeted to the endoplasmic reticulum (ER), we detected significant intracellular thermogenesis in mouse embryonic fibroblast (MEF) cells. Temperatures reached at least 8 °C higher than the external environment (40 °C), resulting in exceptionally high ER temperatures similar to those previously described for mitochondria. Mild heat-induced thermogenesis in the ER of MEF cells was likely due to the uncoupling of the Ca2+/ATPase (SERCA) pump. The high ER temperatures initiated a pronounced cytosolic heat-shock response in MEF cells, which was significantly lower in U2OS cells in which both the ER thermogenesis and SERCA pump uncoupling were absent. Our results suggest that depending on intrinsic cellular properties, mild hyperthermia-induced intracellular thermogenesis defines the cellular response mechanism and determines the outcome of hyperthermic stress.
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Affiliation(s)
- Barbara Dukic
- Laboratory of Molecular Stress Biology, Institute of Biochemistry, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
- Doctoral School of Environmental Sciences, Faculty of Science and Informatics, University of Szeged, 6720 Szeged, Hungary
| | - Zsófia Ruppert
- Laboratory of Molecular Stress Biology, Institute of Biochemistry, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
- Doctoral School of Biology, Faculty of Science and Informatics, University of Szeged, 6720 Szeged, Hungary
| | - Melinda E Tóth
- Laboratory of Molecular Stress Biology, Institute of Biochemistry, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
| | - Ákos Hunya
- Laboratory of Molecular Stress Biology, Institute of Biochemistry, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
| | - Ágnes Czibula
- Laboratory of DNA Damage and Nuclear Dynamics, Institute of Genetics, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
- Department of Immunology, University of Szeged, 6720 Szeged, Hungary
| | - Péter Bíró
- Department of Optics and Quantum Electronics, University of Szeged, 6720 Szeged, Hungary
| | - Ádám Tiszlavicz
- Laboratory of Molecular Stress Biology, Institute of Biochemistry, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
| | - Mária Péter
- Laboratory of Molecular Stress Biology, Institute of Biochemistry, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
| | - Gábor Balogh
- Laboratory of Molecular Stress Biology, Institute of Biochemistry, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
| | - Miklós Erdélyi
- Department of Optics and Quantum Electronics, University of Szeged, 6720 Szeged, Hungary
| | - Gyula Timinszky
- Laboratory of DNA Damage and Nuclear Dynamics, Institute of Genetics, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
| | - László Vígh
- Laboratory of Molecular Stress Biology, Institute of Biochemistry, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
| | - Imre Gombos
- Laboratory of Molecular Stress Biology, Institute of Biochemistry, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
| | - Zsolt Török
- Laboratory of Molecular Stress Biology, Institute of Biochemistry, HUN-REN Biological Research Centre, 6726 Szeged, Hungary
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3
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Bergkamp DJ, Neumaier JF. How omics is revealing new roles for glia in addiction. Glia 2024. [PMID: 38894643 DOI: 10.1002/glia.24584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 06/05/2024] [Accepted: 06/07/2024] [Indexed: 06/21/2024]
Abstract
Experiments to study the biology of addiction have historically focused on the mechanisms through which drugs of abuse drive changes in the functioning of neurons and neural circuits. Glia have often been ignored in these studies, however, and this has left many questions in the field unanswered, particularly, surrounding how glia contribute to changes in synaptic plasticity, regulation of neuroinflammation, and functioning of neural ensembles given massive changes in signaling across the CNS. Omics methods (transcriptomics, translatomics, epigenomics, proteomics, metabolomics, and others) have expanded researchers' abilities to generate hypotheses and carry out mechanistic studies of glial cells during acquisition of drug taking, intoxication, withdrawal, and relapse to drug seeking. Here, we present a survey of how omics technological advances are revising our understanding of astrocytes, microglia, oligodendrocytes, and ependymal cells in addiction biology.
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Affiliation(s)
- David J Bergkamp
- Department of Pharmacology, University of Washington, Seattle, Washington, USA
- VISN 20 Mental Illness Research, Education and Clinical Center, VA Puget Sound Health Care System, Seattle, Washington, USA
| | - John F Neumaier
- Department of Pharmacology, University of Washington, Seattle, Washington, USA
- VISN 20 Mental Illness Research, Education and Clinical Center, VA Puget Sound Health Care System, Seattle, Washington, USA
- Department of Psychiatry & Behavioral Sciences, University of Washington, Seattle, Washington, USA
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4
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Pinto CM, Schnepper AP, Trindade PHE, Cardoso LH, Fioretto MN, Justulin LA, Zanelli CF, Valente GT. The joint action of yeast eisosomes and membraneless organelles in response to ethanol stress. Heliyon 2024; 10:e31561. [PMID: 38818138 PMCID: PMC11137566 DOI: 10.1016/j.heliyon.2024.e31561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 05/13/2024] [Accepted: 05/17/2024] [Indexed: 06/01/2024] Open
Abstract
Elevated ethanol concentrations in yeast affect the plasma membrane. The plasma membrane in yeast has many lipid-protein complexes, such as Pma1 (MCP), Can1 (MCC), and the eisosome complex. We investigated the response of eisosomes, MCPs, and membraneless structures to ethanol stress. We found a correlation between ethanol stress and proton flux with quick acidification of the medium. Moreover, ethanol stress influences the symporter expression in stressed cells. We also suggest that acute stress from ethanol leads to increases in eisosome size and SG number: we hypothesized that eisosomes may protect APC symporters and accumulate an mRNA decay protein in ethanol-stressed cells. Our findings suggest that the joint action of these factors may provide a protective effect on cells under ethanol stress.
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Affiliation(s)
- Camila Moreira Pinto
- Laboratory of Applied Biotechnology. São Paulo State University (UNESP). Botucatu, Brazil
| | | | - Pedro Henrique Esteves Trindade
- Department of Population Health and Pathobiology College of Veterinary Medicine, North Carolina State University (NCSU) Raleigh, USA
| | - Luiz Henrique Cardoso
- Laboratory of Applied Biotechnology. São Paulo State University (UNESP). Botucatu, Brazil
| | - Matheus Naia Fioretto
- Department of Structural and Functional Biology, Institute of Biosciences. São Paulo State University (UNESP). Botucatu, Brazil
| | - Luís Antônio Justulin
- Department of Structural and Functional Biology, Institute of Biosciences. São Paulo State University (UNESP). Botucatu, Brazil
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5
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Nguyen SLT, Nguyen THT, Do TT, Nguyen TT, Le TH, Nguyen TAT, Kimata Y. Induction of Endoplasmic Reticulum Stress by Prodigiosin in Yeast Saccharomyces cerevisiae. Curr Issues Mol Biol 2024; 46:1768-1776. [PMID: 38534732 DOI: 10.3390/cimb46030116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 02/19/2024] [Accepted: 02/22/2024] [Indexed: 03/28/2024] Open
Abstract
Prodigiosin, a red pigment produced by numerous bacterial species, exerts various antibiotic effects on prokaryotic and eukaryotic organisms. For instance, human carcinoma cell lines appear to suffer from endoplasmic reticulum (ER) stress in the presence of prodigiosin. Here, we demonstrated that prodigiosin also triggers the unfolded-protein response (UPR), which is a cytoprotective response against ER stress, in yeast Saccharomyces cerevisiae. An S. cerevisiae mutant carrying a UPR-deficient mutation was hypersensitive to prodigiosin. Our observations cumulatively indicate that protein folding in the ER is impaired by prodigiosin, illustrating a new mode of action.
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Affiliation(s)
- Sy Le Thanh Nguyen
- Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Caugiay District, Hanoi 10600, Vietnam
| | - Thi Hien Trang Nguyen
- Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Caugiay District, Hanoi 10600, Vietnam
| | - Thi Tuyen Do
- Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Caugiay District, Hanoi 10600, Vietnam
| | - Thi Thao Nguyen
- Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Caugiay District, Hanoi 10600, Vietnam
| | - Thanh Hoang Le
- Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Caugiay District, Hanoi 10600, Vietnam
| | - Thi Anh Tuyet Nguyen
- Institute of Biotechnology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Caugiay District, Hanoi 10600, Vietnam
| | - Yukio Kimata
- Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
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6
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Wang D, He M, Zhang M, Yang H, Huang J, Zhou R, Jin Y, Wu C. Food yeasts: occurrence, functions, and stress tolerance in the brewing of fermented foods. Crit Rev Food Sci Nutr 2023; 63:12136-12149. [PMID: 35875880 DOI: 10.1080/10408398.2022.2098688] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
With the rapid development of systems biology technology, there is a deeper understanding of the molecular biological mechanisms and physiological characteristics of microorganisms. Yeasts are widely used in the food industry with their excellent fermentation performances. While due to the complex environments of food production, yeasts have to suffer from various stress factors. Thus, elucidating the stress mechanisms of food yeasts and proposing potential strategies to improve tolerance have been widely concerned. This review summarized the recent signs of progress in the variety, functions, and stress tolerance of food yeasts. Firstly, the main food yeasts occurred in fermented foods, and the taxonomy levels are demonstrated. Then, the main functions of yeasts including aroma enhancer, safety performance enhancer, and fermentation period reducer are discussed. Finally, the stress response mechanisms of yeasts and the strategies to improve the stress tolerance of cells are reviewed. Based on sorting out these related recent researches systematically, we hope that this review can provide help and approaches to further exert the functions of food yeasts and improve food production efficiency.
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Affiliation(s)
- Dingkang Wang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Muwen He
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Min Zhang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Huan Yang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Jun Huang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Rongqing Zhou
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Yao Jin
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Chongde Wu
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
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7
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Ishiwata-Kimata Y, Kimata Y. Fundamental and Applicative Aspects of the Unfolded Protein Response in Yeasts. J Fungi (Basel) 2023; 9:989. [PMID: 37888245 PMCID: PMC10608004 DOI: 10.3390/jof9100989] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/28/2023] Open
Abstract
Upon the dysfunction or functional shortage of the endoplasmic reticulum (ER), namely, ER stress, eukaryotic cells commonly provoke a protective gene expression program called the unfolded protein response (UPR). The molecular mechanism of UPR has been uncovered through frontier genetic studies using Saccharomyces cerevisiae as a model organism. Ire1 is an ER-located transmembrane protein that directly senses ER stress and is activated as an RNase. During ER stress, Ire1 promotes the splicing of HAC1 mRNA, which is then translated into a transcription factor that induces the expression of various genes, including those encoding ER-located molecular chaperones and protein modification enzymes. While this mainstream intracellular UPR signaling pathway was elucidated in the 1990s, new intriguing insights have been gained up to now. For instance, various additional factors allow UPR evocation strictly in response to ER stress. The UPR machineries in other yeasts and fungi, including pathogenic species, are another important research topic. Moreover, industrially beneficial yeast strains carrying an enforced and enlarged ER have been produced through the artificial and constitutive induction of the UPR. In this article, we review canonical and up-to-date insights concerning the yeast UPR, mainly from the viewpoint of the functions and regulation of Ire1 and HAC1.
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Affiliation(s)
| | - Yukio Kimata
- Division of Biological Science, Graduate School of Science and Technology, Nara Institute of Science and Technology, Nara 630-0192, Japan
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8
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Gupta P, Kaur N, Kumar V, Gupta A, Gupta S, Dua A, Injeti E, Mittal A. Evaluation of cinnamaldehyde derivatives as potential protective agents against oxidative-stress induced myotube atrophy using chemical, biological and computational analysis. Bioorg Chem 2023; 139:106661. [PMID: 37354662 DOI: 10.1016/j.bioorg.2023.106661] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 05/14/2023] [Accepted: 06/06/2023] [Indexed: 06/26/2023]
Abstract
Skeletal muscle atrophy, associated with increased morbidity, mortality and poor quality of life, is a metabolic disorder with no FDA approved drug. Oxidative stress is one of the key mediators of atrophy that influences various cell signaling molecules. The goal of this study is to identify potential antioxidant agents that could be used to treat atrophy. In this study in vitro and in situ screening of different cinnamaldehyde (CNA) derivatives for their antioxidant effects was done along with computational analysis to understand the relationship between their chemical structure and biological activity. Data show that 2-hydroxycinnamaldehyde (2HCNA) worked better than other CNA analogues at physiological pH, while 4-Fluoro-2-methoxycinnamaldehyde (4FoCNA) showed the maximum antioxidant activity under acidic conditions. However, these derivatives (2HCNA and 4FoCNA) were found to be toxic to the cultured myotubes (mature myofiber) under both physiological and pathophysiological conditions. Immunofluorescence, bright-field microscopic and biochemical studies conducted using live C2C12 cells showed that pre-incubation with other CNA analogues i.e. 2-methoxycinnamaldehyde (2MeCNA) and 2-benzyloxycinnamaldehyde (2BzCNA) not only maintained the normal morphology of myotubes but also protected them from H2O2-induced atrophy. These compounds (2MeCNA and 2BzCNA) showed higher stability and antioxidant potential, as indicated by computer simulation data analyzed by Density Functional Theory (DFT) based molecular modeling. Overall, the chemical, biological, and computational studies reveal the therapeutic potential of CNA analogues (BzCNA and MeCNA) against oxidative-stress induced muscle atrophy in C2C12 cells.
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Affiliation(s)
- Prachi Gupta
- Skeletal Muscle Laboratory, Institute of Integrated and Honors Studies, Kurukshetra University, Kurukshetra, Haryana 136119, India
| | - Nirmaljeet Kaur
- Skeletal Muscle Laboratory, Institute of Integrated and Honors Studies, Kurukshetra University, Kurukshetra, Haryana 136119, India
| | - Vinod Kumar
- Department of Chemistry, Central University, Mahendergarh, Haryana, India
| | - Amit Gupta
- Department of Chemistry, Dronacharya Government College, Gurugram, Haryana, India
| | - Sanjeev Gupta
- Skeletal Muscle Laboratory, Institute of Integrated and Honors Studies, Kurukshetra University, Kurukshetra, Haryana 136119, India
| | - Anita Dua
- Skeletal Muscle Laboratory, Institute of Integrated and Honors Studies, Kurukshetra University, Kurukshetra, Haryana 136119, India
| | - Elisha Injeti
- Department of Pharmaceutical Sciences, Cedarville University School of Pharmacy, Cedarville, OH, USA
| | - Ashwani Mittal
- Skeletal Muscle Laboratory, Institute of Integrated and Honors Studies, Kurukshetra University, Kurukshetra, Haryana 136119, India.
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9
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Ge X, Wang J, Wang X, Liu Y, Dang C, Suo R, Sun J. Evaluation of Indigenous Yeasts Screened from Chinese Vineyards as Potential Starters for Improving Wine Aroma. Foods 2023; 12:3073. [PMID: 37628071 PMCID: PMC10453611 DOI: 10.3390/foods12163073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 08/05/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023] Open
Abstract
Exploitation of the biodiversity of native wine yeast is a means of modifying the sensory characteristics of wine. Samples from different regions in China were analysed to screen native isolates as potential starter cultures. Through morphological and molecular biological analyses, we found six species, belonging to four genera (Hanseniaspora, Saccharomyces, Rhodotorula and Metschnikowia). These species were subjected to stress tolerance assays (ethanol, glucose, SO2 and pH), enzymatic activity tests (sulphite reductase activity, β-glucosidase activity and protease activity) and fermentation tests. Saccharomyces cerevisiae showed a high tolerance to ethanol and completed fermentation independently. Hanseniaspora demonstrated good enzymatic activity and completed sequential fermentation. The fermentation experiment showed that the PCT4 strain had the best aroma complexity. This study provides a reference for selecting new starters from the perspective of flavour enzymes and tolerance and diversifying the sensory quality of wines from the region.
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Affiliation(s)
- Xiaoxin Ge
- College of Food Science and Technology, Hebei Agricultural University, Baoding 071000, China; (X.G.)
| | - Jie Wang
- College of Food Science and Technology, Hebei Agricultural University, Baoding 071000, China; (X.G.)
- Hebei Technology Innovation Center of Agricultural Products Processing, Baoding 071001, China
| | - Xiaodi Wang
- College of Food Science and Technology, Hebei Agricultural University, Baoding 071000, China; (X.G.)
| | - Yaqiong Liu
- College of Food Science and Technology, Hebei Agricultural University, Baoding 071000, China; (X.G.)
- Hebei Technology Innovation Center of Agricultural Products Processing, Baoding 071001, China
| | - Chao Dang
- College of Food Science and Technology, Hebei Agricultural University, Baoding 071000, China; (X.G.)
- Hebei Technology Innovation Center of Agricultural Products Processing, Baoding 071001, China
| | - Ran Suo
- College of Food Science and Technology, Hebei Agricultural University, Baoding 071000, China; (X.G.)
- Hebei Technology Innovation Center of Agricultural Products Processing, Baoding 071001, China
| | - Jianfeng Sun
- College of Food Science and Technology, Hebei Agricultural University, Baoding 071000, China; (X.G.)
- Hebei Technology Innovation Center of Agricultural Products Processing, Baoding 071001, China
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10
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Hrach VL, King WR, Nelson LD, Conklin S, Pollock JA, Patton-Vogt J. The acyltransferase Gpc1 is both a target and an effector of the unfolded protein response in Saccharomyces cerevisiae. J Biol Chem 2023; 299:104884. [PMID: 37269946 PMCID: PMC10331479 DOI: 10.1016/j.jbc.2023.104884] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 05/25/2023] [Accepted: 05/27/2023] [Indexed: 06/05/2023] Open
Abstract
The unfolded protein response (UPR) is sensitive to proteotoxic and membrane bilayer stress, both of which are sensed by the ER protein Ire1. When activated, Ire1 splices HAC1 mRNA, producing a transcription factor that targets genes involved in proteostasis and lipid metabolism, among others. The major membrane lipid phosphatidylcholine (PC) is subject to phospholipase-mediated deacylation, producing glycerophosphocholine (GPC), followed by reacylation of GPC through the PC deacylation/reacylation pathway (PC-DRP). The reacylation events occur via a two-step process catalyzed first by the GPC acyltransferase Gpc1, followed by acylation of the lyso-PC molecule by Ale1. However, whether Gpc1 is critical for ER bilayer homeostasis is unclear. Using an improved method for C14-choline-GPC radiolabeling, we first show that loss of Gpc1 results in abrogation of PC synthesis through PC-DRP and that Gpc1 colocalizes with the ER. We then probe the role of Gpc1 as both a target and an effector of the UPR. Exposure to the UPR-inducing compounds tunicamycin, DTT, and canavanine results in a Hac1-dependent increase in GPC1 message. Further, cells lacking Gpc1 exhibit increased sensitivity to those proteotoxic stressors. Inositol limitation, known to induce the UPR via bilayer stress, also induces GPC1 expression. Finally, we show that loss of GPC1 induces the UPR. A gpc1Δ mutant displays upregulation of the UPR in strains expressing a mutant form of Ire1 that is unresponsive to unfolded proteins, indicating that bilayer stress is responsible for the observed upregulation. Collectively, our data indicate an important role for Gpc1 in yeast ER bilayer homeostasis.
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Affiliation(s)
- Victoria Lee Hrach
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - William R King
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Laura D Nelson
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Shane Conklin
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - John A Pollock
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Jana Patton-Vogt
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA.
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11
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Eigenfeld M, Wittmann L, Kerpes R, Schwaminger S, Becker T. Quantification methods of determining brewer's and pharmaceutical yeast cell viability: accuracy and impact of nanoparticles. Anal Bioanal Chem 2023; 415:3201-3213. [PMID: 37083758 PMCID: PMC10287788 DOI: 10.1007/s00216-023-04676-w] [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: 02/20/2023] [Revised: 03/23/2023] [Accepted: 03/28/2023] [Indexed: 04/22/2023]
Abstract
For industrial processes, a fast, precise, and reliable method of determining the physiological state of yeast cells, especially viability, is essential. However, an increasing number of processes use magnetic nanoparticles (MNPs) for yeast cell manipulation, but their impact on yeast cell viability and the assay itself is unclear. This study tested the viability of Saccharomyces pastorianus ssp. carlsbergensis and Pichia pastoris by comparing traditional colourimetric, high-throughput, and growth assays with membrane fluidity. Results showed that methylene blue staining is only reliable for S. pastorianus cells with good viability, being erroneous in low viability (R2 = 0.945; [Formula: see text] = 5.78%). In comparison, the fluorescence microscopy-based assay of S. pastorianus demonstrated a coefficient of determination of R2 = 0.991 at [Formula: see text] ([Formula: see text] = 2.50%) and flow cytometric viability determination using carboxyfluorescein diacetate (CFDA), enabling high-throughput analysis of representative cell numbers; R2 = 0.972 ([Formula: see text]; [Formula: see text] = 3.89%). Membrane fluidity resulted in a non-linear relationship with the viability of the yeast cells ([Formula: see text]). We also determined similar results using P. pastoris yeast. In addition, we demonstrated that MNPs affected methylene blue staining by overestimating viability. The random forest model has been shown to be a precise method for classifying nanoparticles and yeast cells and viability differentiation in flow cytometry by using CFDA. Moreover, CFDA and membrane fluidity revealed precise results for both yeasts, also in the presence of nanoparticles, enabling fast and reliable determination of viability in many experiments using MNPs for yeast cell manipulation or separation.
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Affiliation(s)
- Marco Eigenfeld
- Chair of Brewing and Beverage Technology, Technical University of Munich, TUM School of Life Science, Weihenstephaner Steig 20, 85354 Freising, Germany
| | - Leonie Wittmann
- Chair of Bioseparation Engineering, Technical University of Munich, TUM School of Engineering and Design, Boltzmannstr. 15, 85748 Garching, Germany
| | - Roland Kerpes
- Chair of Brewing and Beverage Technology, Technical University of Munich, TUM School of Life Science, Weihenstephaner Steig 20, 85354 Freising, Germany
| | - Sebastian Schwaminger
- Chair of Bioseparation Engineering, Technical University of Munich, TUM School of Engineering and Design, Boltzmannstr. 15, 85748 Garching, Germany
- Division of Medicinal Chemistry, Medical University of Graz, Otto-Loewi Research Center, Neue Stiftingtalstr. 6, 8010 Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Thomas Becker
- Chair of Brewing and Beverage Technology, Technical University of Munich, TUM School of Life Science, Weihenstephaner Steig 20, 85354 Freising, Germany
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12
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Celik C, Lee SYT, Yap WS, Thibault G. Endoplasmic reticulum stress and lipids in health and diseases. Prog Lipid Res 2023; 89:101198. [PMID: 36379317 DOI: 10.1016/j.plipres.2022.101198] [Citation(s) in RCA: 37] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 11/03/2022] [Accepted: 11/09/2022] [Indexed: 11/14/2022]
Abstract
The endoplasmic reticulum (ER) is a complex and dynamic organelle that regulates many cellular pathways, including protein synthesis, protein quality control, and lipid synthesis. When one or multiple ER roles are dysregulated and saturated, the ER enters a stress state, which, in turn, activates the highly conserved unfolded protein response (UPR). By sensing the accumulation of unfolded proteins or lipid bilayer stress (LBS) at the ER, the UPR triggers pathways to restore ER homeostasis and eventually induces apoptosis if the stress remains unresolved. In recent years, it has emerged that the UPR works intimately with other cellular pathways to maintain lipid homeostasis at the ER, and so does at cellular levels. Lipid distribution, along with lipid anabolism and catabolism, are tightly regulated, in part, by the ER. Dysfunctional and overwhelmed lipid-related pathways, independently or in combination with ER stress, can have reciprocal effects on other cellular functions, contributing to the development of diseases. In this review, we summarize the current understanding of the UPR in response to proteotoxic stress and LBS and the breadth of the functions mitigated by the UPR in different tissues and in the context of diseases.
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Affiliation(s)
- Cenk Celik
- School of Biological Sciences, Nanyang Technological University, Singapore
| | | | - Wei Sheng Yap
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Guillaume Thibault
- School of Biological Sciences, Nanyang Technological University, Singapore; Mechanobiology Institute, National University of Singapore, Singapore; Institute of Molecular and Cell Biology, A*STAR, Singapore.
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13
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Wang D, Mi T, Huang J, Zhou R, Jin Y, Wu C. Metabolomics analysis of salt tolerance of Zygosaccharomyces rouxii and guided exogenous fatty acid addition for improved salt tolerance. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2022; 102:6263-6272. [PMID: 35510311 DOI: 10.1002/jsfa.11975] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 03/09/2022] [Accepted: 05/04/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Zygosaccharomyces rouxii plays an irreplaceable role in the manufacture of traditional fermented foods, which are produced in a high-salt environment. However, there is little research on strategies for improving salt tolerance of Z. rouxii. RESULTS In this study, metabolomics was used to reveal the changes in intracellular metabolites under salt stress, and the results show that most of the carbohydrate contents decreased, the contents of xanthohumol and glycerol increased (fold change 4.07 and 5.35, respectively), while the contents of galactinol, xylitol and d-threitol decreased (fold change -9.43, -5.83 and -3.59, respectively). In addition, the content of four amino acids and six organic acids decreased, while that of the ten nucleotides increased. Notably, except for stearic acid (C18:0), all fatty acid contents increased. Guided by the metabolomics results, the effect of addition of seven exogenous fatty acids (C12:0, C14:0, C16:0, C18:0, C16:1, C18:1, and C18:2) on the salt tolerance of Z. rouxii was analyzed, and the results suggested that four exogenous fatty acids (C12:0, C16:0, C16:1, and C18:1) can increase the biomass yield and maximum growth rate. Physiological analyses demonstrated that exogenous fatty acids could regulate the distribution of fatty acids in the cell membrane, increase the degree of unsaturation, improve membrane fluidity, and maintain cell integrity, morphology and surface roughness. CONCLUSION These results are applicable to revealing the metabolic mechanisms of Z. rouxii under salt stress and screening potential protective agents to improve stress resistance by adding exogenous fatty acids. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Dingkang Wang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Ting Mi
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Jun Huang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Rongqing Zhou
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Yao Jin
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
| | - Chongde Wu
- College of Biomass Science and Engineering, Sichuan University, Chengdu, China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education, Sichuan University, Chengdu, China
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14
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Bonatto D. The multiple roles of lipid metabolism in yeast physiology during beer fermentation. Genet Mol Biol 2022; 45:e20210325. [PMID: 36149459 PMCID: PMC9511687 DOI: 10.1590/1678-4685-gmb-2021-0325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 07/17/2022] [Indexed: 11/21/2022] Open
Abstract
The ability of brewing yeasts (Saccharomyces cerevisiae and Saccharomyces pastorianus) to cope with the toxic effects of ethanol during beer fermentation depends on the modulation of lipid and lipid droplets (LDs) biosynthesis, which affects membrane fluidity. However, it has been demonstrated that lipids and LDs can modulate different biological mechanisms associated to ethanol tolerance, including proteostasis and autophagy, leading to the hypothesis that lipid and LDs biosynthesis are integrative processes necessary for ethanol tolerance in yeast. Supporting this hypothesis, a transcriptome and systems biology analyses indicated the upregulation of autophagy, lipid biosynthesis, and proteostasis (ALP)-associated genes in lager yeast during beer fermentation, whose respective proteins interact in a shortest-pathway ALP network. These results indicated a cross-communication between various pathways linked to inter-organelle autophagy, lipid metabolism, and proteostasis (ALP) during lager beer fermentation, thus highlighting the importance of lipids for beer fermentation.
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Affiliation(s)
- Diego Bonatto
- Universidade Federal do Rio Grande do Sul, Centro de Biotecnologia da UFRGS, Laboratório de Biologia Molecular e Computacional, Departamento de Biologia Molecular e Biotecnologia, Porto Alegre, RS, Brazil
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15
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Ribeiro RA, Bourbon-Melo N, Sá-Correia I. The cell wall and the response and tolerance to stresses of biotechnological relevance in yeasts. Front Microbiol 2022; 13:953479. [PMID: 35966694 PMCID: PMC9366716 DOI: 10.3389/fmicb.2022.953479] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 07/11/2022] [Indexed: 01/18/2023] Open
Abstract
In industrial settings and processes, yeasts may face multiple adverse environmental conditions. These include exposure to non-optimal temperatures or pH, osmotic stress, and deleterious concentrations of diverse inhibitory compounds. These toxic chemicals may result from the desired accumulation of added-value bio-products, yeast metabolism, or be present or derive from the pre-treatment of feedstocks, as in lignocellulosic biomass hydrolysates. Adaptation and tolerance to industrially relevant stress factors involve highly complex and coordinated molecular mechanisms occurring in the yeast cell with repercussions on the performance and economy of bioprocesses, or on the microbiological stability and conservation of foods, beverages, and other goods. To sense, survive, and adapt to different stresses, yeasts rely on a network of signaling pathways to modulate the global transcriptional response and elicit coordinated changes in the cell. These pathways cooperate and tightly regulate the composition, organization and biophysical properties of the cell wall. The intricacy of the underlying regulatory networks reflects the major role of the cell wall as the first line of defense against a wide range of environmental stresses. However, the involvement of cell wall in the adaptation and tolerance of yeasts to multiple stresses of biotechnological relevance has not received the deserved attention. This article provides an overview of the molecular mechanisms involved in fine-tuning cell wall physicochemical properties during the stress response of Saccharomyces cerevisiae and their implication in stress tolerance. The available information for non-conventional yeast species is also included. These non-Saccharomyces species have recently been on the focus of very active research to better explore or control their biotechnological potential envisaging the transition to a sustainable circular bioeconomy.
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Affiliation(s)
- Ricardo A. Ribeiro
- Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
- Associate Laboratory i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Nuno Bourbon-Melo
- Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Isabel Sá-Correia
- Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
- Associate Laboratory i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
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16
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Zou S, Jia Y, He Q, Zhang K, Ban R, Hong J, Zhang M. Comparison of the Unfolded Protein Response in Cellobiose Utilization of Recombinant Angel- and W303-1A-Derived Yeast Expressing β-Glucosidase. Front Bioeng Biotechnol 2022; 10:837720. [PMID: 35433667 PMCID: PMC9008459 DOI: 10.3389/fbioe.2022.837720] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 03/07/2022] [Indexed: 11/13/2022] Open
Abstract
The unfolded protein response (UPR) is one of the most important protein quality control mechanisms in cells. At least, three factors are predicted to activate the UPR in yeast cells during fermentation. Using UPRE-lacZ as a reporter, we constructed two indicator strains, KZ and WZ, based on Angel-derived K-a and W303-1A strains, respectively, and investigated their UPR response to tunicamycin, ethanol, and acetic acid. Then, four strains carrying plasmids BG-cwp2 and BG were obtained to realize the displaying and secretion of β-glucosidase, respectively. The results of cellobiose utilization assays indicated interactions between the UPR and the metabolic burden between the strain source, anchoring moiety, oxygen supply, and cellobiose concentration. Meanwhile, as expected, growth (OD600), β-glucosidase, and β-galactosidase activities were shown to have a positive inter-relationship, in which the values of the KZ-derived strains were far lower than those of the WZ-derived strains. Additionally, extra metabolic burden by displaying over secreting was also much more serious in strain KZ than in strain WZ. The maximum ethanol titer of the four strains (KZ (BG-cwp2), KZ (BG), WZ (BG-cwp2), and WZ (BG)) in oxygen-limited 10% cellobiose fermentation was 3.173, 5.307, 5.495, and 5.486% (v/v), respectively, and the acetic acid titer ranged from 0.038 to 0.060% (v/v). The corresponding maximum values of the ratio of β-galactosidase activity to that of the control were 3.30, 5.29, 6.45, and 8.72, respectively. Under aerobic conditions with 2% cellobiose, those values were 3.79, 4.97, 6.99, and 7.67, respectively. A comparison of the results implied that β-glucosidase expression durably induced the UPR, and the effect of ethanol and acetic acid depended on the titer produced. Further study is necessary to identify ethanol- or acid-specific target gene expression. Taken together, our results indicated that the host strain W303-1A is a better secretory protein producer, and the first step to modify strain K-a for cellulosic ethanol fermentation would be to relieve the bottleneck of UPR capacity. The results of the present study will help to identify candidate host strains and optimize expression and fermentation by quantifying UPR induction.
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Affiliation(s)
- Shaolan Zou
- Tianjin R&D Center for Petrochemical Technology, Tianjin University, Tianjin, China
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Key Laboratory for Green Chemical Technology of Ministry of Education, Tianjin University, Tianjin, China
- *Correspondence: Shaolan Zou, ; Jiefang Hong,
| | - Yudie Jia
- Tianjin R&D Center for Petrochemical Technology, Tianjin University, Tianjin, China
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Qing He
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Kun Zhang
- Tianjin R&D Center for Petrochemical Technology, Tianjin University, Tianjin, China
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
| | - Rui Ban
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Jiefang Hong
- Tianjin R&D Center for Petrochemical Technology, Tianjin University, Tianjin, China
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Key Laboratory for Green Chemical Technology of Ministry of Education, Tianjin University, Tianjin, China
- *Correspondence: Shaolan Zou, ; Jiefang Hong,
| | - Minhua Zhang
- Tianjin R&D Center for Petrochemical Technology, Tianjin University, Tianjin, China
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Key Laboratory for Green Chemical Technology of Ministry of Education, Tianjin University, Tianjin, China
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17
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Lairón-Peris M, Routledge SJ, Linney JA, Alonso-del-Real J, Spickett CM, Pitt AR, Guillamón JM, Barrio E, Goddard AD, Querol A. Lipid Composition Analysis Reveals Mechanisms of Ethanol Tolerance in the Model Yeast Saccharomyces cerevisiae. Appl Environ Microbiol 2021; 87:e0044021. [PMID: 33771787 PMCID: PMC8174666 DOI: 10.1128/aem.00440-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 03/23/2021] [Indexed: 12/30/2022] Open
Abstract
Saccharomyces cerevisiae is an important unicellular yeast species within the biotechnological and the food and beverage industries. A significant application of this species is the production of ethanol, where concentrations are limited by cellular toxicity, often at the level of the cell membrane. Here, we characterize 61 S. cerevisiae strains for ethanol tolerance and further analyze five representatives with various ethanol tolerances. The most tolerant strain, AJ4, was dominant in coculture at 0 and 10% ethanol. Unexpectedly, although it does not have the highest noninhibitory concentration or MIC, MY29 was the dominant strain in coculture at 6% ethanol, which may be linked to differences in its basal lipidome. Although relatively few lipidomic differences were observed between strains, a significantly higher phosphatidylethanolamine concentration was observed in the least tolerant strain, MY26, at 0 and 6% ethanol compared to the other strains that became more similar at 10%, indicating potential involvement of this lipid with ethanol sensitivity. Our findings reveal that AJ4 is best able to adapt its membrane to become more fluid in the presence of ethanol and that lipid extracts from AJ4 also form the most permeable membranes. Furthermore, MY26 is least able to modulate fluidity in response to ethanol, and membranes formed from extracted lipids are least leaky at physiological ethanol concentrations. Overall, these results reveal a potential mechanism of ethanol tolerance and suggest a limited set of membrane compositions that diverse yeast species use to achieve this. IMPORTANCE Many microbial processes are not implemented at the industrial level because the product yield is poorer and more expensive than can be achieved by chemical synthesis. It is well established that microbes show stress responses during bioprocessing, and one reason for poor product output from cell factories is production conditions that are ultimately toxic to the cells. During fermentative processes, yeast cells encounter culture media with a high sugar content, which is later transformed into high ethanol concentrations. Thus, ethanol toxicity is one of the major stresses in traditional and more recent biotechnological processes. We have performed a multilayer phenotypic and lipidomic characterization of a large number of industrial and environmental strains of Saccharomyces to identify key resistant and nonresistant isolates for future applications.
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Affiliation(s)
- M. Lairón-Peris
- Food Biotechnology Department, Institute of Agrochemistry and Food Technology, CSIC, Valencia, Spain
| | - S. J. Routledge
- College of Health and Life Sciences, Aston University, Birmingham, United Kingdom
| | - J. A. Linney
- College of Health and Life Sciences, Aston University, Birmingham, United Kingdom
| | - J. Alonso-del-Real
- Food Biotechnology Department, Institute of Agrochemistry and Food Technology, CSIC, Valencia, Spain
| | - C. M. Spickett
- College of Health and Life Sciences, Aston University, Birmingham, United Kingdom
| | - A. R. Pitt
- College of Health and Life Sciences, Aston University, Birmingham, United Kingdom
- Manchester Institute of Biotechnology and Department of Chemistry, University of Manchester, Manchester, United Kingdom
| | - J. M. Guillamón
- Food Biotechnology Department, Institute of Agrochemistry and Food Technology, CSIC, Valencia, Spain
| | - E. Barrio
- Food Biotechnology Department, Institute of Agrochemistry and Food Technology, CSIC, Valencia, Spain
- Genetics Department, University of Valencia, Valencia, Spain
| | - A. D. Goddard
- College of Health and Life Sciences, Aston University, Birmingham, United Kingdom
| | - A. Querol
- Food Biotechnology Department, Institute of Agrochemistry and Food Technology, CSIC, Valencia, Spain
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18
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Ammendolia DA, Bement WM, Brumell JH. Plasma membrane integrity: implications for health and disease. BMC Biol 2021; 19:71. [PMID: 33849525 PMCID: PMC8042475 DOI: 10.1186/s12915-021-00972-y] [Citation(s) in RCA: 96] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Accepted: 02/01/2021] [Indexed: 12/12/2022] Open
Abstract
Plasma membrane integrity is essential for cellular homeostasis. In vivo, cells experience plasma membrane damage from a multitude of stressors in the extra- and intra-cellular environment. To avoid lethal consequences, cells are equipped with repair pathways to restore membrane integrity. Here, we assess plasma membrane damage and repair from a whole-body perspective. We highlight the role of tissue-specific stressors in health and disease and examine membrane repair pathways across diverse cell types. Furthermore, we outline the impact of genetic and environmental factors on plasma membrane integrity and how these contribute to disease pathogenesis in different tissues.
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Affiliation(s)
- Dustin A Ammendolia
- Cell Biology Program, Hospital for Sick Children, 686 Bay Street PGCRL, Toronto, ON, M5G 0A4, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, M5S 1A1, Canada
| | - William M Bement
- Center for Quantitative Cell Imaging and Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - John H Brumell
- Cell Biology Program, Hospital for Sick Children, 686 Bay Street PGCRL, Toronto, ON, M5G 0A4, Canada. .,Department of Molecular Genetics, University of Toronto, Toronto, ON, M5S 1A1, Canada. .,Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A1, Canada. .,SickKids IBD Centre, Hospital for Sick Children, Toronto, ON, M5G 0A4, Canada.
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19
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Ren X, He Z, Lin X, Lin X, Liang Z, Liu D, Huang Y, Fang Z. Screening and evaluation of Monascus purpureus FJMR24 for enhancing the raw material utilization rate in rice wine brewing. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2021; 101:185-193. [PMID: 32623720 DOI: 10.1002/jsfa.10630] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 06/24/2020] [Accepted: 07/05/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND The rapid development of the rice wine industry has increased the demand for raw materials worldwide. A fungal strain with good adaptability to rice wine brewing conditions, which can also enhance the utilization rate of raw materials (URRM), thus increasing the production efficiency, was sought in the present research. RESULTS The strain FJMR24 was successfully isolated and screened from 35 fermentation starters and exhibited high amylase activity (2200.9 ± 18.5 U g-1 ) and high glucoamylase activity (2330.4 ± 31.9 U g-1 ). Based on a morphological examination and a sequence analysis of the internal transcribed spacer (ITS) gene and β-tubulin gene, FJMR24 was identified as Monascus purpureus, which is an edible and versatile fungus that plays a dominant role in the processing of Hong Qu. A moderate pH of 5-6 under incubation at 35 °C for 5-6 days was favorable for the growth and enzyme production of FJMR24. The strain could also tolerate the extreme conditions of 15-45 °C, 18% ethanol (v/v), and an acidity of pH 2. The excellent fermentation adaptability of FJMR24 might enable it to retain high enzyme activity during rice wine brewing. As a result of the action of FJMR24, the URRM of the base liquor increased by around 26% due to increased starch hydrolysis efficiency, which was mainly due to the high unit enzyme activity of FJMR24. CONCLUSION This study provides perspectives for the application of a M. purpureus strain with high starch hydrolysis activity for enhancing the URRM in traditional rice wine brewing. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Xiangyun Ren
- Institute of Agricultural Engineering Technology, Fujian Academy of Agricultural Sciences, Fuzhou, China
- Fujian Key Laboratory of Agricultural Products (Food) Processing, Fuzhou, China
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Zhigang He
- Institute of Agricultural Engineering Technology, Fujian Academy of Agricultural Sciences, Fuzhou, China
- Fujian Key Laboratory of Agricultural Products (Food) Processing, Fuzhou, China
| | - Xiaozi Lin
- Institute of Agricultural Engineering Technology, Fujian Academy of Agricultural Sciences, Fuzhou, China
- Fujian Key Laboratory of Agricultural Products (Food) Processing, Fuzhou, China
| | - Xiaojie Lin
- Institute of Agricultural Engineering Technology, Fujian Academy of Agricultural Sciences, Fuzhou, China
- Fujian Key Laboratory of Agricultural Products (Food) Processing, Fuzhou, China
| | - Zhangcheng Liang
- Institute of Agricultural Engineering Technology, Fujian Academy of Agricultural Sciences, Fuzhou, China
- Fujian Key Laboratory of Agricultural Products (Food) Processing, Fuzhou, China
| | - Di Liu
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Yingying Huang
- Institute of Agricultural Engineering Technology, Fujian Academy of Agricultural Sciences, Fuzhou, China
- Fujian Key Laboratory of Agricultural Products (Food) Processing, Fuzhou, China
| | - Zhongxiang Fang
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, VIC, Australia
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Wu CC, Ohashi T, Misaki R, Limtong S, Fujiyama K. Ethanol and H2O2 stresses enhance lipid production in an oleaginous Rhodotorula toruloides thermotolerant mutant L1-1. FEMS Yeast Res 2020; 20:5859489. [DOI: 10.1093/femsyr/foaa030] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 06/02/2020] [Indexed: 01/07/2023] Open
Abstract
Abstract
Stress tolerance is a desired characteristic of yeast strains for industrial applications. Stress tolerance has been well described in Saccharomyces yeasts but has not yet been characterized in oleaginous Rhodotorula yeasts even though they are considered promising platforms for lipid production owing to their outstanding lipogenicity. In a previous study, the thermotolerant strain L1–1 was isolated from R. toruloides DMKU3-TK16 (formerly Rhodosporidium toruloides). In this study, we aimed to further examine the ability of this strain to tolerate other stresses and its lipid productivity under various stress conditions. We found that the L1–1 strain could tolerate not only thermal stress but also oxidative stress (ethanol and H2O2), osmotic stress (glucose) and a cell membrane disturbing reagent (DMSO). Our results also showed that the L1–1 strain exhibited enhanced ability to maintain ROS homeostasis, stronger cell wall strength and increased levels of unsaturated membrane lipids under various stresses. Moreover, we also demonstrated that ethanol-induced stress significantly increased the lipid productivity of the thermotolerant L1–1. The thermotolerant L1–1 was also found to produce a higher lipid titer under the dual ethanol-H2O2 stress than under non-stress conditions. This is the first report to indicate that ethanol stress can induce lipid production in an R. toruloides thermotolerant strain.
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Affiliation(s)
- Chih-Chan Wu
- International Center for Biotechnology, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565–0871, Japan
| | - Takao Ohashi
- Department of Microbiology, Faculty of Science, Kasetsart University, 50 Phaholyothin Road, Bangkok 10900, Bangkok 10900, Thailand
| | - Ryo Misaki
- International Center for Biotechnology, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565–0871, Japan
| | - Savitree Limtong
- Department of Microbiology, Faculty of Science, Kasetsart University, 50 Phaholyothin Road, Bangkok 10900, Bangkok 10900, Thailand
| | - Kazuhito Fujiyama
- International Center for Biotechnology, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565–0871, Japan
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The roles and applications of chaotropes and kosmotropes in industrial fermentation processes. World J Microbiol Biotechnol 2020; 36:89. [PMID: 32507915 DOI: 10.1007/s11274-020-02865-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 06/04/2020] [Indexed: 12/13/2022]
Abstract
Chaotropicity has long been recognised as a property of some compounds. Chaotropes tend to disrupt non-covalent interactions in biological macromolecules (e.g. proteins and nucleic acids) and supramolecular assemblies (e.g. phospholipid membranes). This results in the destabilisation and unfolding of these macromolecules and assemblies. Unsurprisingly, these compounds are typically harmful to living cells since they act against multiple targets, comprising cellular integrity and function. Kosmotropes are the opposite of chaotropes and these compounds promote the ordering and rigidification of biological macromolecules and assemblies. Since many biological macromolecules have optimum levels of flexibility, kosmotropes can also inhibit their activity and can be harmful to cells. Some products of industrial fermentations, most notably alcohols, are chaotropic. This property can be a limiting factor on rates of production and yields. It has been hypothesised that the addition of kosmotropes may mitigate the chaotropicity of some fermentation products. Some microbes naturally adapt to chaotropic environments by producing kosmotropic compatible solutes. Exploitation of this in industrial fermentations has been hampered by scientific and economic issues. The cost of the kosmotropes and their removal during purification needs to be considered. We lack a complete understanding of the chemistry of chaotropicity and a robust, quantitative framework for estimating overall chaotropicities of mixtures. This makes it difficult to predict the amount of kosmotrope required to neutralise the chaotropicity. This review considers examples of industrial fermentations where chaotropicity is an issue and suggests possible mitigations.
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Evaluation of indigenous non-Saccharomyces yeasts isolated from a South Australian vineyard for their potential as wine starter cultures. Int J Food Microbiol 2020; 312:108373. [DOI: 10.1016/j.ijfoodmicro.2019.108373] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 09/09/2019] [Accepted: 09/20/2019] [Indexed: 02/06/2023]
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Covre EA, Silva LFL, Bastos RG, Ceccato-Antonini SR. Interaction of 4-ethylphenol, pH, sucrose and ethanol on the growth and fermentation capacity of the industrial strain of Saccharomyces cerevisiae PE-2. World J Microbiol Biotechnol 2019; 35:136. [PMID: 31432249 DOI: 10.1007/s11274-019-2714-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Accepted: 08/11/2019] [Indexed: 11/28/2022]
Abstract
Volatile phenols such as 4-ethylphenol are produced from hydroxycinnamic acids by Dekkera bruxellensis, an important yeast contaminating alcoholic fermentations. 4-ethylphenol results from the decarboxylation and reduction of p-coumaric acid, a compound found in sugarcane musts. In wine, volatile phenols are responsible by sensorial alterations whereas in the context of bioethanol fermentation, little is known about their effects on the main yeast, Saccharomyces cerevisiae. Here we evaluated the interaction of 4-ethylphenol and pH, sucrose and ethanol on the growth and fermentation capacity of the industrial strain of S. cerevisiae PE-2. A central compound rotational design was utilized to evaluate the effect of 4-ethylphenol, pH, ethanol and sucrose concentration on the yeast maximum specific growth rate (µmax) in microplate experiments in YPS medium (Yeast extract-Peptone-Sucrose), at 30 °C. Following, single-cycle fermentations in YPS medium, pH 4.5, 17% sucrose, at 30 °C, with 4-ethylphenol in concentrations of 10 and 20 mg L-1 being added at the start or after 4 h of fermentation, were carried out. 4-ethylphenol affected µmax of S. cerevisiae in situations that resemble the conditions of industrial bioethanol production, especially the low pH of the fermentation medium and the high ethanol concentration because of the anaerobic sucrose uptake. The addition of 4-ethylphenol on fermentation resulted in significant effect on the cell yeast concentration, pH and alcohol production, with significant decrease from 86% to the range of 65-74% in the fermentative efficiency. The industrial yeast S. cerevisiae PE-2 growth and fermentative capacity were affected by the presence of 4-ethylphenol, a metabolite produced by D. bruxellensis, which may contribute to explain the impact of this yeast on bioethanol industrial production.
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Affiliation(s)
- Elizabete A Covre
- Dept Tecnologia Agroindustrial e Socio-Economia Rural, Universidade Federal de São Carlos - Centro de Ciencias Agrarias, Via Anhanguera, km 174, Araras, SP, 13600-970, Brazil
| | - Lincon F L Silva
- Dept Tecnologia Agroindustrial e Socio-Economia Rural, Universidade Federal de São Carlos - Centro de Ciencias Agrarias, Via Anhanguera, km 174, Araras, SP, 13600-970, Brazil
| | - Reinaldo G Bastos
- Dept Tecnologia Agroindustrial e Socio-Economia Rural, Universidade Federal de São Carlos - Centro de Ciencias Agrarias, Via Anhanguera, km 174, Araras, SP, 13600-970, Brazil
| | - Sandra R Ceccato-Antonini
- Dept Tecnologia Agroindustrial e Socio-Economia Rural, Universidade Federal de São Carlos - Centro de Ciencias Agrarias, Via Anhanguera, km 174, Araras, SP, 13600-970, Brazil.
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Sugiyama M, Fukaya T, Moon JY, Ishida K, Matsushita A, Kim SY, Yeo SH. Analysis and enhancement of the ethanol resistance of Pichia kudriavzevii N77-4, a strain newly isolated from the Korean traditional fermentation starter Nuruk, for improved fermentation performance. ACTA ACUST UNITED AC 2019. [DOI: 10.1088/1742-6596/1282/1/012062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Stress tolerance phenotype of industrial yeast: industrial cases, cellular changes, and improvement strategies. Appl Microbiol Biotechnol 2019; 103:6449-6462. [DOI: 10.1007/s00253-019-09993-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 06/17/2019] [Accepted: 06/17/2019] [Indexed: 10/26/2022]
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Chen Y, Cheng L, Zhang X, Cao J, Wu Z, Zheng X. Transcriptomic and proteomic effects of (-)-epigallocatechin 3-O-(3-O-methyl) gallate (EGCG3”Me) treatment on ethanol-stressed Saccharomyces cerevisiae cells. Food Res Int 2019; 119:67-75. [DOI: 10.1016/j.foodres.2019.01.061] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 01/22/2019] [Accepted: 01/23/2019] [Indexed: 12/23/2022]
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Development of Robust Yeast Strains for Lignocellulosic Biorefineries Based on Genome-Wide Studies. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2019; 58:61-83. [PMID: 30911889 DOI: 10.1007/978-3-030-13035-0_3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Lignocellulosic biomass has been widely studied as the renewable feedstock for the production of biofuels and biochemicals. Budding yeast Saccharomyces cerevisiae is commonly used as a cell factory for bioconversion of lignocellulosic biomass. However, economic bioproduction using fermentable sugars released from lignocellulosic feedstocks is still challenging. Due to impaired cell viability and fermentation performance by various inhibitors that are present in the cellulosic hydrolysates, robust yeast strains resistant to various stress environments are highly desired. Here, we summarize recent progress on yeast strain development for the production of biofuels and biochemical using lignocellulosic biomass. Genome-wide studies which have contributed to the elucidation of mechanisms of yeast stress tolerance are reviewed. Key gene targets recently identified based on multiomics analysis such as transcriptomic, proteomic, and metabolomics studies are summarized. Physiological genomic studies based on zinc sulfate supplementation are highlighted, and novel zinc-responsive genes involved in yeast stress tolerance are focused. The dependence of host genetic background of yeast stress tolerance and roles of histones and their modifications are emphasized. The development of robust yeast strains based on multiomics analysis benefits economic bioconversion of lignocellulosic biomass.
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Mechanisms of Yeast Adaptation to Wine Fermentations. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2019; 58:37-59. [PMID: 30911888 DOI: 10.1007/978-3-030-13035-0_2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Cells face genetic and/or environmental changes in order to outlast and proliferate. Characterization of changes after stress at different "omics" levels is crucial to understand the adaptation of yeast to changing conditions. Wine fermentation is a stressful situation which yeast cells have to cope with. Genome-wide analyses extend our cellular physiology knowledge by pointing out the mechanisms that contribute to sense the stress caused by these perturbations (temperature, ethanol, sulfites, nitrogen, etc.) and related signaling pathways. The model organism, Saccharomyces cerevisiae, was studied in response to industrial stresses and changes at different cellular levels (transcriptomic, proteomic, and metabolomics), which were followed statically and/or dynamically in the short and long terms. This chapter focuses on the response of yeast cells to the diverse stress situations that occur during wine fermentations, which induce perturbations, including nutritional changes, ethanol stress, temperature stress, oxidative stress, etc.
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Tran DM, Takagi H, Kimata Y. Categorization of endoplasmic reticulum stress as accumulation of unfolded proteins or membrane lipid aberrancy using yeast Ire1 mutants. Biosci Biotechnol Biochem 2018; 83:326-329. [PMID: 30319071 DOI: 10.1080/09168451.2018.1530098] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Endoplasmic reticulum (ER)-located protein Ire1 triggers the unfolded protein response against ER-stressing stimuli, which are categorized as ER accumulation of unfolded proteins or membrane lipid-related aberrancy. Here we demonstrate that by using yeast Ire1 mutants, we can distinguish the category to which a stress-inducing stimulus belongs. For instance, ethanol was found to activate Ire1 through both types of cellular damage.
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Affiliation(s)
- Duc Minh Tran
- a Graduate School of Science and Technology , Nara Institute of Science and Technology , Nara , Japan.,b Institute of Biotechnology , Vietnam Academy of Science and Technology , Ha Noi , Viet Nam
| | - Hiroshi Takagi
- a Graduate School of Science and Technology , Nara Institute of Science and Technology , Nara , Japan
| | - Yukio Kimata
- a Graduate School of Science and Technology , Nara Institute of Science and Technology , Nara , Japan
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Navarro-Tapia E, Querol A, Pérez-Torrado R. Membrane fluidification by ethanol stress activates unfolded protein response in yeasts. Microb Biotechnol 2018; 11:465-475. [PMID: 29469174 PMCID: PMC5902320 DOI: 10.1111/1751-7915.13032] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 09/05/2017] [Accepted: 11/05/2017] [Indexed: 11/28/2022] Open
Abstract
The toxic effect of ethanol is one of the most important handicaps for many biotechnological applications of yeasts, such as bioethanol production. Elucidation of ethanol stress response will help to improve yeast performance in biotechnological processes. In the yeast Saccharomyces cerevisiae, ethanol stress has been recently described as an activator of the unfolded protein response (UPR), a conserved intracellular signalling pathway that regulates the transcription of ER homoeostasis‐related genes. However, the signal and activation mechanism has not yet been unravelled. Here, we studied UPR's activation after ethanol stress and observed the upregulation of the key target genes, like INO1, involved in lipid metabolism. We found that inositol content influenced UPR activation after ethanol stress and we observed significant changes in lipid composition, which correlate with a major membrane fluidity alteration by this amphipathic molecule. Then, we explored the hypothesis that membrane fluidity changes cause UPR activation upon ethanol stress by studying UPR response against fluidification or rigidification agents and by studying a mutant, erg2, with altered membrane fluidity. The results suggest that the membrane fluidification effects of ethanol and other agents are the signal for UPR activation, a mechanism that has been proposed in higher eukaryotes.
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Affiliation(s)
- Elisabet Navarro-Tapia
- Instituto de Agroquímica y Tecnología de los Alimentos, IATA-CSIC, E-46980, Paterna, Valencia, Spain
| | - Amparo Querol
- Instituto de Agroquímica y Tecnología de los Alimentos, IATA-CSIC, E-46980, Paterna, Valencia, Spain
| | - Roberto Pérez-Torrado
- Instituto de Agroquímica y Tecnología de los Alimentos, IATA-CSIC, E-46980, Paterna, Valencia, Spain
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