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Khamwachirapithak P, Sae-Tang K, Mhuantong W, Tanapongpipat S, Zhao XQ, Liu CG, Wei DQ, Champreda V, Runguphan W. Optimizing Ethanol Production in Saccharomyces cerevisiae at Ambient and Elevated Temperatures through Machine Learning-Guided Combinatorial Promoter Modifications. ACS Synth Biol 2023; 12:2897-2908. [PMID: 37681736 PMCID: PMC10594650 DOI: 10.1021/acssynbio.3c00199] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Indexed: 09/09/2023]
Abstract
Bioethanol has gained popularity in recent decades as an ecofriendly alternative to fossil fuels due to increasing concerns about global climate change. However, economically viable ethanol fermentation remains a challenge. High-temperature fermentation can reduce production costs, but Saccharomyces cerevisiae yeast strains normally ferment poorly under high temperatures. In this study, we present a machine learning (ML) approach to optimize bioethanol production in S. cerevisiae by fine-tuning the promoter activities of three endogenous genes. We created 216 combinatorial strains of S. cerevisiae by replacing native promoters with five promoters of varying strengths to regulate ethanol production. Promoter replacement resulted in a 63% improvement in ethanol production at 30 °C. We created an ML-guided workflow by utilizing XGBoost to train high-performance models based on promoter strengths and cellular metabolite concentrations obtained from ethanol production of 216 combinatorial strains at 30 °C. This strategy was then applied to optimize ethanol production at 40 °C, where we selected 31 strains for experimental fermentation. This reduced experimental load led to a 7.4% increase in ethanol production in the second round of the ML-guided workflow. Our study offers a comprehensive library of promoter strength modifications for key ethanol production enzymes, showcasing how machine learning can guide yeast strain optimization and make bioethanol production more cost-effective and efficient. Furthermore, we demonstrate that metabolic engineering processes can be accelerated and optimized through this approach.
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Affiliation(s)
- Peerapat Khamwachirapithak
- National
Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency
(NSTDA) 111 Thailand Science Park, Phahonyothin Road, Khlong
Nueng, Khlong Luang, Pathum Thani 12120, Thailand
| | - Kittapong Sae-Tang
- National
Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency
(NSTDA) 111 Thailand Science Park, Phahonyothin Road, Khlong
Nueng, Khlong Luang, Pathum Thani 12120, Thailand
| | - Wuttichai Mhuantong
- National
Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency
(NSTDA) 111 Thailand Science Park, Phahonyothin Road, Khlong
Nueng, Khlong Luang, Pathum Thani 12120, Thailand
| | - Sutipa Tanapongpipat
- National
Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency
(NSTDA) 111 Thailand Science Park, Phahonyothin Road, Khlong
Nueng, Khlong Luang, Pathum Thani 12120, Thailand
| | - Xin-Qing Zhao
- State
Key Laboratory of Microbial Metabolism, Joint International Research
Laboratory of Metabolic & Developmental Sciences, School of Life
Sciences and Biotechnology, Shanghai Jiao
Tong University, Shanghai 200240, People’s
Republic of China
| | - Chen-Guang Liu
- State
Key Laboratory of Microbial Metabolism, Joint International Research
Laboratory of Metabolic & Developmental Sciences, School of Life
Sciences and Biotechnology, Shanghai Jiao
Tong University, Shanghai 200240, People’s
Republic of China
| | - Dong-Qing Wei
- Department
of Bioinformatics and Biological Statistics, School of Life Sciences
and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
| | - Verawat Champreda
- National
Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency
(NSTDA) 111 Thailand Science Park, Phahonyothin Road, Khlong
Nueng, Khlong Luang, Pathum Thani 12120, Thailand
| | - Weerawat Runguphan
- National
Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency
(NSTDA) 111 Thailand Science Park, Phahonyothin Road, Khlong
Nueng, Khlong Luang, Pathum Thani 12120, Thailand
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Topaloğlu A, Esen Ö, Turanlı-Yıldız B, Arslan M, Çakar ZP. From Saccharomyces cerevisiae to Ethanol: Unlocking the Power of Evolutionary Engineering in Metabolic Engineering Applications. J Fungi (Basel) 2023; 9:984. [PMID: 37888240 PMCID: PMC10607480 DOI: 10.3390/jof9100984] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 09/25/2023] [Accepted: 09/28/2023] [Indexed: 10/28/2023] Open
Abstract
Increased human population and the rapid decline of fossil fuels resulted in a global tendency to look for alternative fuel sources. Environmental concerns about fossil fuel combustion led to a sharp move towards renewable and environmentally friendly biofuels. Ethanol has been the primary fossil fuel alternative due to its low carbon emission rates, high octane content and comparatively facile microbial production processes. In parallel to the increased use of bioethanol in various fields such as transportation, heating and power generation, improvements in ethanol production processes turned out to be a global hot topic. Ethanol is by far the leading yeast output amongst a broad spectrum of bio-based industries. Thus, as a well-known platform microorganism and native ethanol producer, baker's yeast Saccharomyces cerevisiae has been the primary subject of interest for both academic and industrial perspectives in terms of enhanced ethanol production processes. Metabolic engineering strategies have been primarily adopted for direct manipulation of genes of interest responsible in mainstreams of ethanol metabolism. To overcome limitations of rational metabolic engineering, an alternative bottom-up strategy called inverse metabolic engineering has been widely used. In this context, evolutionary engineering, also known as adaptive laboratory evolution (ALE), which is based on random mutagenesis and systematic selection, is a powerful strategy to improve bioethanol production of S. cerevisiae. In this review, we focus on key examples of metabolic and evolutionary engineering for improved first- and second-generation S. cerevisiae bioethanol production processes. We delve into the current state of the field and show that metabolic and evolutionary engineering strategies are intertwined and many metabolically engineered strains for bioethanol production can be further improved by powerful evolutionary engineering strategies. We also discuss potential future directions that involve recent advancements in directed genome evolution, including CRISPR-Cas9 technology.
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Affiliation(s)
- Alican Topaloğlu
- Department of Molecular Biology and Genetics, Faculty of Science and Letters, Istanbul Technical University, Istanbul 34469, Türkiye; (A.T.); (Ö.E.)
- Dr. Orhan Öcalgiray Molecular Biology, Biotechnology and Genetics Research Center (ITU-MOBGAM), Istanbul Technical University, Istanbul 34469, Türkiye;
| | - Ömer Esen
- Department of Molecular Biology and Genetics, Faculty of Science and Letters, Istanbul Technical University, Istanbul 34469, Türkiye; (A.T.); (Ö.E.)
- Dr. Orhan Öcalgiray Molecular Biology, Biotechnology and Genetics Research Center (ITU-MOBGAM), Istanbul Technical University, Istanbul 34469, Türkiye;
| | - Burcu Turanlı-Yıldız
- Dr. Orhan Öcalgiray Molecular Biology, Biotechnology and Genetics Research Center (ITU-MOBGAM), Istanbul Technical University, Istanbul 34469, Türkiye;
| | - Mevlüt Arslan
- Department of Genetics, Faculty of Veterinary Medicine, Van Yüzüncü Yıl University, Van 65000, Türkiye;
| | - Zeynep Petek Çakar
- Department of Molecular Biology and Genetics, Faculty of Science and Letters, Istanbul Technical University, Istanbul 34469, Türkiye; (A.T.); (Ö.E.)
- Dr. Orhan Öcalgiray Molecular Biology, Biotechnology and Genetics Research Center (ITU-MOBGAM), Istanbul Technical University, Istanbul 34469, Türkiye;
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3
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Ceccato-Antonini SR, Covre EA. From baker's yeast to genetically modified budding yeasts: the scientific evolution of bioethanol industry from sugarcane. FEMS Yeast Res 2020; 20:6021367. [PMID: 33406233 DOI: 10.1093/femsyr/foaa065] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 12/02/2020] [Indexed: 12/22/2022] Open
Abstract
The peculiarities of Brazilian fuel ethanol fermentation allow the entry of native yeasts that may dominate over the starter strains of Saccharomyces cerevisiae and persist throughout the sugarcane harvest. The switch from the use of baker's yeast as starter to selected budding yeasts obtained by a selective pressure strategy was followed by a wealth of genomic information that enabled the understanding of the superiority of selected yeast strains. This review describes how the process of yeast selection evolved in the sugarcane-based bioethanol industry, the selection criteria and recent advances in genomics that could advance the fermentation process. The prospective use of genetically modified yeast strains, specially designed for increased robustness and product yield, with special emphasis on those obtained by the CRISPR (clustered regularly interspaced palindromic repeats)-Cas9 (CRISPR-associated protein 9) genome-editing approach, is discussed as a possible solution to confer higher performance and stability to the fermentation process for fuel ethanol production.
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Affiliation(s)
- Sandra Regina Ceccato-Antonini
- Laboratory of Agricultural and Molecular Microbiology, Dept Tecnologia Agroindustrial e Socioeconomia Rural, Centro de Ciências Agrárias, Universidade Federal de São Carlos, Via Anhanguera, km 174, 13600-970 Araras, São Paulo State, Brazil
| | - Elizabete Aparecida Covre
- Laboratory of Agricultural and Molecular Microbiology, Dept Tecnologia Agroindustrial e Socioeconomia Rural, Centro de Ciências Agrárias, Universidade Federal de São Carlos, Via Anhanguera, km 174, 13600-970 Araras, São Paulo State, Brazil
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4
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Kvasko AY, Isayenkov SV, Dmytruk KV, Sibirny AA, Blume YB, Yemets AI. Obtaining Wheat (Triticum aestivum L.) Lines with Yeast Genes for Trehalose Biosynthesis. CYTOL GENET+ 2020. [DOI: 10.3103/s0095452720040088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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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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Ruchala J, Kurylenko OO, Dmytruk KV, Sibirny AA. Construction of advanced producers of first- and second-generation ethanol in Saccharomyces cerevisiae and selected species of non-conventional yeasts (Scheffersomyces stipitis, Ogataea polymorpha). J Ind Microbiol Biotechnol 2019; 47:109-132. [PMID: 31637550 PMCID: PMC6970964 DOI: 10.1007/s10295-019-02242-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 10/01/2019] [Indexed: 12/20/2022]
Abstract
This review summarizes progress in the construction of efficient yeast ethanol producers from glucose/sucrose and lignocellulose. Saccharomyces cerevisiae is the major industrial producer of first-generation ethanol. The different approaches to increase ethanol yield and productivity from glucose in S. cerevisiae are described. Construction of the producers of second-generation ethanol is described for S. cerevisiae, one of the best natural xylose fermenters, Scheffersomyces stipitis and the most thermotolerant yeast known Ogataea polymorpha. Each of these organisms has some advantages and drawbacks. S. cerevisiae is the primary industrial ethanol producer and is the most ethanol tolerant natural yeast known and, however, cannot metabolize xylose. S. stipitis can effectively ferment both glucose and xylose and, however, has low ethanol tolerance and requires oxygen for growth. O. polymorpha grows and ferments at high temperatures and, however, produces very low amounts of ethanol from xylose. Review describes how the mentioned drawbacks could be overcome.
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Affiliation(s)
- Justyna Ruchala
- Department of Microbiology and Biotechnology, University of Rzeszow, Zelwerowicza 4, 35-601, Rzeszow, Poland
| | - Olena O Kurylenko
- Department of Molecular Genetics and Biotechnology, Institute of Cell Biology, NAS of Ukraine, Drahomanov Street, 14/16, Lviv, 79005, Ukraine
| | - Kostyantyn V Dmytruk
- Department of Molecular Genetics and Biotechnology, Institute of Cell Biology, NAS of Ukraine, Drahomanov Street, 14/16, Lviv, 79005, Ukraine
| | - Andriy A Sibirny
- Department of Microbiology and Biotechnology, University of Rzeszow, Zelwerowicza 4, 35-601, Rzeszow, Poland.
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7
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Saini P, Beniwal A, Kokkiligadda A, Vij S. Response and tolerance of yeast to changing environmental stress during ethanol fermentation. Process Biochem 2018. [DOI: 10.1016/j.procbio.2018.07.001] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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8
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Yin H, Wang Y, He Y, Xing L, Zhang X, Wang S, Qi X, Zheng Z, Lu J, Miao J. Cloning and expression analysis of tps, and cryopreservation research of trehalose from Antarctic strain Pseudozyma sp. 3 Biotech 2017; 7:343. [PMID: 28955640 PMCID: PMC5610133 DOI: 10.1007/s13205-017-0983-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 09/15/2017] [Indexed: 12/24/2022] Open
Abstract
Trehalose is a non-reducing disaccharide sugar that widely exists in a variety of organisms, such as bacteria and eukaryotes except the vertebrates. It plays an important role in a number of critical metabolic functions especially in response to stressful environmental conditions. However, the biosynthetic pathways of trehalose in cold-adapted yeast and its responses to temperature and salinity changes remain little understood. In this study, the genome of Antarctic-isolated Pseudozyma sp. NJ7 was generated from which we identified the gene coding for trehalose phosphate synthase (TPS1) and trehalose phosphate phosphatase (TPS2), the two enzymes most critical for trehalose production. The whole draft genome length of Pseudozyma sp. NJ7 was 18,021,233 bp, and encoded at least 34 rRNA operons and 72 tRNAs. The open reading frame of tps1 contained 1827 nucleotide encoding 608 amino acids with a molecular weight of 67.64 kDa, and an isoelectric point of 5.54, while tps2 contained 3948 nucleotide encoding 1315 amino acids with a molecular weight of 144.47 kDa and an isoelectric point of 6.36. The TPS1 and TPS2 protein sequences were highly homologous to Moesziomyces antarcticus T-34, but TPS2 had obvious specificity and differently with others which suggest species specificity and different evolutionary history. Expression level of tps1 gene was strongly influenced by temperature and high salinity. In addition, addition of 0.5% trehalose preserved yeast cells in the short term but was not effective for cryopreservation for more than 5 days, but still suggesting that exogenous trehalose could indeed significantly improve the survival of yeast cells under freezing conditions. Our results provided new insights on the molecular basis of cold adaptations of Antarctic Pseudozyma sp., and also generated new information on the roles trehalose play in yeast tolerance to extreme conditions in the extreme Antarctic environments.
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Affiliation(s)
- Hua Yin
- State Key Laboratory of Biological Fermentation Engineering of Beer, Tsingtao Brewery Co. Ltd, Qingdao, 266061 China
| | - Yibin Wang
- The First Institute of Oceanography, State Oceanic Administration, Qingdao, 266061 China
- Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235 China
| | - Yingying He
- The First Institute of Oceanography, State Oceanic Administration, Qingdao, 266061 China
| | - Lei Xing
- State Key Laboratory of Biological Fermentation Engineering of Beer, Tsingtao Brewery Co. Ltd, Qingdao, 266061 China
| | - Xiufang Zhang
- Clinical Laboratory, Qingdao Hiser Medical Center, Qingdao, 266033 China
| | - Shuai Wang
- The First Institute of Oceanography, State Oceanic Administration, Qingdao, 266061 China
- Marine and Fisheries Monitoring Center of Sanya, Sanya, 572000 China
| | - Xiaoqing Qi
- The First Institute of Oceanography, State Oceanic Administration, Qingdao, 266061 China
- Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000 China
| | - Zhou Zheng
- The First Institute of Oceanography, State Oceanic Administration, Qingdao, 266061 China
- Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235 China
| | - Jian Lu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122 China
| | - Jinlai Miao
- The First Institute of Oceanography, State Oceanic Administration, Qingdao, 266061 China
- Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235 China
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9
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Genetic Enhancement of Saccharomyces cerevisiae for First and Second Generation Ethanol Production. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1201/b19347-11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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10
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Sun X, Zhang CY, Wu MY, Fan ZH, Liu SN, Zhu WB, Xiao DG. MAL62 overexpression and NTH1 deletion enhance the freezing tolerance and fermentation capacity of the baker's yeast in lean dough. Microb Cell Fact 2016; 15:54. [PMID: 27039899 PMCID: PMC4819290 DOI: 10.1186/s12934-016-0453-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 03/09/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Trehalose is related to several types of stress responses, especially freezing response in baker's yeast (Saccharomyces cerevisiae). It is desirable to manipulate trehalose-related genes to create yeast strains that better tolerate freezing-thaw stress with improved fermentation capacity, which are in high demand in the baking industry. RESULTS The strain overexpressing MAL62 gene showed increased trehalose content and cell viability after prefermention-freezing and long-term frozen. Deletion of NTH1 in combination of MAL62 overexpression further strengthens freezing tolerance and improves the leavening ability after freezing-thaw stress. CONCLUSIONS The mutants of the industrial baker's yeast with enhanced freezing tolerance and leavening ability in lean dough were developed by genetic engineering. These strains had excellent potential industrial applications.
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Affiliation(s)
- Xi Sun
- College of Biological Engineering, Tianjin Agricultural University, Tianjin, 300384, People's Republic of China.,Tianjin Engineering Research Center of Agricultural Products Processing, Tianjin, 300384, People's Republic of China
| | - Cui-Ying Zhang
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China.,College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
| | - Ming-Yue Wu
- Diagreat Biotechnologies., Ltd, Beijing, 101111, People's Republic of China
| | - Zhi-Hua Fan
- College of Biological Engineering, Tianjin Agricultural University, Tianjin, 300384, People's Republic of China.,Tianjin Engineering Research Center of Agricultural Products Processing, Tianjin, 300384, People's Republic of China
| | - Shan-Na Liu
- College of Biological Engineering, Tianjin Agricultural University, Tianjin, 300384, People's Republic of China.,Tianjin Engineering Research Center of Agricultural Products Processing, Tianjin, 300384, People's Republic of China
| | - Wen-Bi Zhu
- College of Biological Engineering, Tianjin Agricultural University, Tianjin, 300384, People's Republic of China
| | - Dong-Guang Xiao
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China. .,College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China.
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Hagiwara D, Sakamoto K, Abe K, Gomi K. Signaling pathways for stress responses and adaptation in Aspergillus species: stress biology in the post-genomic era. Biosci Biotechnol Biochem 2016; 80:1667-80. [PMID: 27007956 DOI: 10.1080/09168451.2016.1162085] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Aspergillus species are among the most important filamentous fungi in terms of industrial use and because of their pathogenic or toxin-producing features. The genomes of several Aspergillus species have become publicly available in this decade, and genomic analyses have contributed to an integrated understanding of fungal biology. Stress responses and adaptation mechanisms have been intensively investigated using the accessible genome infrastructure. Mitogen-activated protein kinase (MAPK) cascades have been highlighted as being fundamentally important in fungal adaptation to a wide range of stress conditions. Reverse genetics analyses have uncovered the roles of MAPK pathways in osmotic stress, cell wall stress, development, secondary metabolite production, and conidia stress resistance. This review summarizes the current knowledge on the stress biology of Aspergillus species, illuminating what we have learned from the genomic data in this "post-genomic era."
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Affiliation(s)
- Daisuke Hagiwara
- a Medical Mycology Research Center , Chiba University , Chiba , Japan
| | | | - Keietsu Abe
- c Graduate School of Agricultural Science , Tohoku University , Sendai , Japan
| | - Katsuya Gomi
- c Graduate School of Agricultural Science , Tohoku University , Sendai , Japan
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12
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Becker J, Wittmann C. Advanced Biotechnology: Metabolically Engineered Cells for the Bio-Based Production of Chemicals and Fuels, Materials, and Health-Care Products. Angew Chem Int Ed Engl 2015; 54:3328-50. [DOI: 10.1002/anie.201409033] [Citation(s) in RCA: 223] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Indexed: 12/16/2022]
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13
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Biotechnologie von Morgen: metabolisch optimierte Zellen für die bio-basierte Produktion von Chemikalien und Treibstoffen, Materialien und Gesundheitsprodukten. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201409033] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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14
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Walker ME, Nguyen TD, Liccioli T, Schmid F, Kalatzis N, Sundstrom JF, Gardner JM, Jiranek V. Genome-wide identification of the Fermentome; genes required for successful and timely completion of wine-like fermentation by Saccharomyces cerevisiae. BMC Genomics 2014. [DOI: 10.1186/1471-2164-15-552 and 1880=1880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
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15
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Walker ME, Nguyen TD, Liccioli T, Schmid F, Kalatzis N, Sundstrom JF, Gardner JM, Jiranek V. Genome-wide identification of the Fermentome; genes required for successful and timely completion of wine-like fermentation by Saccharomyces cerevisiae. BMC Genomics 2014. [DOI: 10.1186/1471-2164-15-552 order by 1-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
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16
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Walker ME, Nguyen TD, Liccioli T, Schmid F, Kalatzis N, Sundstrom JF, Gardner JM, Jiranek V. Genome-wide identification of the Fermentome; genes required for successful and timely completion of wine-like fermentation by Saccharomyces cerevisiae. BMC Genomics 2014. [DOI: 10.1186/1471-2164-15-552 order by 8029-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
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17
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Walker ME, Nguyen TD, Liccioli T, Schmid F, Kalatzis N, Sundstrom JF, Gardner JM, Jiranek V. Genome-wide identification of the Fermentome; genes required for successful and timely completion of wine-like fermentation by Saccharomyces cerevisiae. BMC Genomics 2014. [DOI: 10.1186/1471-2164-15-552 order by 8029-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
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18
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Walker ME, Nguyen TD, Liccioli T, Schmid F, Kalatzis N, Sundstrom JF, Gardner JM, Jiranek V. Genome-wide identification of the Fermentome; genes required for successful and timely completion of wine-like fermentation by Saccharomyces cerevisiae. BMC Genomics 2014. [DOI: 10.1186/1471-2164-15-552 order by 1-- gadu] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
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19
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Walker ME, Nguyen TD, Liccioli T, Schmid F, Kalatzis N, Sundstrom JF, Gardner JM, Jiranek V. Genome-wide identification of the Fermentome; genes required for successful and timely completion of wine-like fermentation by Saccharomyces cerevisiae. BMC Genomics 2014. [DOI: 10.1186/1471-2164-15-552 order by 1-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
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20
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Walker ME, Nguyen TD, Liccioli T, Schmid F, Kalatzis N, Sundstrom JF, Gardner JM, Jiranek V. Genome-wide identification of the Fermentome; genes required for successful and timely completion of wine-like fermentation by Saccharomyces cerevisiae. BMC Genomics 2014. [DOI: 10.1186/1471-2164-15-552 order by 8029-- awyx] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
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21
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Identification of a gene, FMP21, whose expression levels are involved in thermotolerance in Saccharomyces cerevisiae. AMB Express 2014; 4:67. [PMID: 25177541 PMCID: PMC4143573 DOI: 10.1186/s13568-014-0067-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 08/09/2014] [Indexed: 12/23/2022] Open
Abstract
Elucidation of the mechanism of high temperature tolerance in yeasts is important for the molecular breeding of high temperature-tolerant yeasts that can be used in bioethanol production. We identified genes whose expression is correlated with the degree of thermotolerance in Saccharomyces cerevisiae by DNA microarray analysis. Gene expression profiles of three S. cerevisiae strains showing different levels of thermotolerance were compared, and we chose three of them as candidate genes. Among these genes, FMP21 was investigated as a thermotolerance-related gene in S. cerevisiae by comparing the growth at high temperature with the gene expression in eight strains. The expression ratio of FMP21 at 37°C was correlated with the doubling time ratio at a coefficient of determination of 0.787. The potential involvement of the Fmp21 in the thermotolerance of yeasts was evaluated. The FMP21 deletion variant showed a decreased respiratory growth rate and increased thermosensitivity. Furthermore, the overexpression of FMP21 improved thermotolerance in yeasts. In conclusion, the function of Fmp21 is important for thermotolerance in yeasts.
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Walker ME, Nguyen TD, Liccioli T, Schmid F, Kalatzis N, Sundstrom JF, Gardner JM, Jiranek V. Genome-wide identification of the Fermentome; genes required for successful and timely completion of wine-like fermentation by Saccharomyces cerevisiae. BMC Genomics 2014; 15:552. [PMID: 24993029 PMCID: PMC4099481 DOI: 10.1186/1471-2164-15-552] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 06/27/2014] [Indexed: 12/21/2022] Open
Abstract
Background Wine fermentation is a harsh ecological niche to which wine yeast are well adapted. The initial high osmotic pressure and acidity of grape juice is followed by nutrient depletion and increasing concentrations of ethanol as the fermentation progresses. Yeast’s adaptation to these and many other environmental stresses, enables successful completion of high-sugar fermentations. Earlier transcriptomic and growth studies have tentatively identified genes important for high-sugar fermentation. Whilst useful, such studies did not consider extended growth (>5 days) in a temporally dynamic multi-stressor environment such as that found in many industrial fermentation processes. Here, we identify genes whose deletion has minimal or no effect on growth, but results in failure to achieve timely completion of the fermentation of a chemically defined grape juice with 200 g L−1 total sugar. Results Micro- and laboratory-scale experimental fermentations were conducted to identify 72 clones from ~5,100 homozygous diploid single-gene yeast deletants, which exhibited protracted fermentation in a high-sugar medium. Another 21 clones (related by gene function, but initially eliminated from the screen because of possible growth defects) were also included. Clustering and numerical enrichment of genes annotated to specific Gene Ontology (GO) terms highlighted the vacuole’s role in ion homeostasis and pH regulation, through vacuole acidification. Conclusion We have identified 93 genes whose deletion resulted in the duration of fermentation being at least 20% longer than the wild type. An extreme phenotype, ‘stuck’ fermentation, was also observed when DOA4, NPT1, PLC1, PTK2, SIN3, SSQ1, TPS1, TPS2 or ZAP1 were deleted. These 93 Fermentation Essential Genes (FEG) are required to complete an extended high-sugar (wine-like) fermentation. Their importance is highlighted in our Fermentation Relevant Yeast Genes (FRYG) database, generated from literature and the fermentation-relevant phenotypic characteristics of null mutants described in the Saccharomyces Genome Database. The 93-gene set is collectively referred to as the ‘Fermentome’. The fact that 10 genes highlighted in this study have not previously been linked to fermentation-related stresses, supports our experimental rationale. These findings, together with investigations of the genetic diversity of industrial strains, are crucial for understanding the mechanisms behind yeast’s response and adaptation to stresses imposed during high-sugar fermentations. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-552) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | | | | | - Vladimir Jiranek
- School of Agriculture, Food and Wine, University of Adelaide, Urrbrae, SA 5064, Australia.
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Development of industrial yeast strain with improved acid- and thermo-tolerance through evolution under continuous fermentation conditions followed by haploidization and mating. J Biosci Bioeng 2014; 118:689-95. [PMID: 24958128 DOI: 10.1016/j.jbiosc.2014.05.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 05/14/2014] [Accepted: 05/18/2014] [Indexed: 11/20/2022]
Abstract
Continuous fermentation using the industrial Saccharomyces cerevisiae diploid strain WW was carried out under acidic or high-temperature conditions to achieve acid- or thermo-tolerant mutants. Mutants isolated at pH 2.5 and 41°C showed improved growth and fermentation ability under acidic and elevated temperature conditions. Haploid strains WW17A1 and WW17A4 obtained from the mutated diploid strain WW17A showed better growth and 4.5-6.5% higher ethanol yields at pH 2.7 than the original strains. Haploid strain WW12T4 obtained from mutated diploid strain WW12T showed 1.25-1.50 times and 2.8-4.7 times higher total cell number and cell viability, respectively, than the original strains at 42°C. Strain AT, which had significantly improved acid- and thermo-tolerance, was developed by mating strain WW17A1 with WW12T4. Batch fermentation at 41°C and pH 3.5 showed that the ethanol concentration and yield achieved during fermentation by strain AT were 55.4 g/L and 72.5%, respectively, which were 10 g/L and 13.4% higher than that of the original strain WW. The present study demonstrates that continuous cultivation followed by haploidization and mating is a powerful approach for enhancing the tolerance of industrial strains.
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Doğan A, Demirci S, Aytekin AÖ, Şahin F. Improvements of tolerance to stress conditions by genetic engineering in Saccharomyces cerevisiae during ethanol production. Appl Biochem Biotechnol 2014; 174:28-42. [PMID: 24908051 DOI: 10.1007/s12010-014-1006-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2013] [Accepted: 05/29/2014] [Indexed: 02/07/2023]
Abstract
Saccharomyces cerevisiae, industrial yeast isolate, has been of great interest in recent years for fuel ethanol production. The ethanol yield and productivity depend on many inhibitory factors during the fermentation process such as temperature, ethanol, compounds released as the result of pretreatment procedures, and osmotic stress. An ideal strain should be able to grow under different stress conditions occurred at different fermentation steps. Development of tolerant yeast strains can be achieved by reprogramming pathways supporting the ethanol metabolism by regulating the energy balance and detoxicification processes. Complex gene interactions should be solved for an in-depth comprehension of the yeast stress tolerance mechanism. Genetic engineering as a powerful biotechnological tool is required to design new strategies for increasing the ethanol fermentation performance. Upregulation of stress tolerance genes by recombinant DNA technology can be a useful approach to overcome inhibitory situations. This review presents the application of several genetic engineering strategies to increase ethanol yield under different stress conditions including inhibitor tolerance, ethanol tolerance, thermotolerance, and osmotolerance.
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Affiliation(s)
- Ayşegül Doğan
- Department of Genetics and BioEngineering, Faculty of Engineering and Architecture, Yeditepe University, 26 Ağustos Campus, Kayisdagi cad., Kayisdagi, TR-34755, Istanbul, Turkey,
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Dynamic metabolic and transcriptional profiling of Rhodococcus sp. strain YYL during the degradation of tetrahydrofuran. Appl Environ Microbiol 2014; 80:2656-64. [PMID: 24532074 DOI: 10.1128/aem.04131-13] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Although tetrahydrofuran-degrading Rhodococcus sp. strain YYL possesses tetrahydrofuran (THF) degradation genes similar to those of other tetrahydrofuran-degrading bacteria, a much higher degradation efficiency has been observed in strain YYL. In this study, nuclear magnetic resonance (NMR)-based metabolomics analyses were performed to explore the metabolic profiling response of strain YYL to exposure to THF. Exposure to THF slightly influenced the metabolome of strain YYL when yeast extract was present in the medium. The metabolic profile of strain YYL over time was also investigated using THF as the sole carbon source to identify the metabolites associated with high-efficiency THF degradation. Lactate, alanine, glutarate, glutamate, glutamine, succinate, lysine, trehalose, trimethylamine-N-oxide (TMAO), NAD(+), and CTP were significantly altered over time in strain YYL grown in 20 mM THF. Real-time quantitative PCR (RT-qPCR) revealed changes in the transcriptional expression levels of 15 genes involved in THF degradation, suggesting that strain YYL could accumulate several disturbances in osmoregulation (trehalose, glutamate, glutamine, etc.), with reduced glycolysis levels, an accelerated tricarboxylic acid cycle, and enhanced protein synthesis. The findings obtained through (1)H NMR metabolomics analyses and the transcriptional expression of the corresponding genes are complementary for exploring the dynamic metabolic profile in organisms.
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Nielsen J, Larsson C, van Maris A, Pronk J. Metabolic engineering of yeast for production of fuels and chemicals. Curr Opin Biotechnol 2013; 24:398-404. [DOI: 10.1016/j.copbio.2013.03.023] [Citation(s) in RCA: 235] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 03/18/2013] [Accepted: 03/27/2013] [Indexed: 01/01/2023]
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Kern C, Wolf C, Bender F, Berger M, Noack S, Schmalz S, Ilg T. Trehalose-6-phosphate synthase from the cat flea Ctenocephalides felis and Drosophila melanogaster: gene identification, cloning, heterologous functional expression and identification of inhibitors by high throughput screening. INSECT MOLECULAR BIOLOGY 2012; 21:456-471. [PMID: 22762304 DOI: 10.1111/j.1365-2583.2012.01151.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Trehalose phosphate synthase (EC 2.4.1.15; TPS) is the crucial enzyme for the biosynthesis of trehalose, the main haemolymph sugar of insects, and therefore a potential insecticidal molecular target. In this study, we report the functional heterologous expression of Drosophila melanogaster TPS, the gene identification, full length cDNA cloning and functional expression of cat flea (Ctenocephalides felis) TPS, and the Michaelis-Menten constants for their specific substrates glucose-6-phosphate and uridinediphosphate-glucose. A novel high throughput screening-compatible TPS assay and its use for the identification of the first potent insect TPS inhibitors from a large synthetic compound collection (>115 000 compounds) is described. One compound class that emerged in this screening, the 4-substituted 2,6-diamino-3,5-dicyano-4H-thiopyrans, was further investigated by analysing preliminary structure-activity relationships. Here, compounds were identified that show low µM to high nM half maximal inhibitory concentrations on insect TPS and that may serve as lead compounds for the development of insecticides with a novel mode of action.
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Affiliation(s)
- C Kern
- Intervet Innovation GmbH, Zur Propstei, 55270 Schwabenheim, Germany
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