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Hsiung RT, Chiu MC, Chou JY. Exogenous Indole-3-Acetic Acid Induced Ethanol Tolerance in Phylogenetically Diverse Saccharomycetales Yeasts. Microbes Environ 2022; 37. [PMID: 35082178 PMCID: PMC8958292 DOI: 10.1264/jsme2.me21053] [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] [Indexed: 11/12/2022] Open
Abstract
Indole-3-acetic acid (IAA) is an exogenous growth regulatory signal that is produced by plants and various microorganisms. Microorganisms have been suggested to cross-communicate with each other through IAA-mediated signaling mechanisms. The IAA-induced tolerance response has been reported in several microorganisms, but has not yet been described in Saccharomycetales yeasts. In the present study, three common stressors (heat, osmotic pressure, and ethanol) were examined in relation to the influence of a pretreatment with IAA on stress tolerance in 12 different lineages of Saccharomyces cerevisiae. The pretreatment with IAA had a significant effect on the induction of ethanol tolerance by reducing the doubling time of S. cerevisiae growth without the pretreatment. However, the pretreatment did not significantly affect the induction of thermo- or osmotolerance. The IAA pretreatment decreased the lethal effects of ethanol on S. cerevisiae cells. Although yeasts produce ethanol to outcompete sympatric microorganisms, IAA is not a byproduct of this process. Nevertheless, the accumulation of IAA indicates an increasing number of microorganisms, and, thus, greater competition for resources. Since the “wine trait” is shared by both phylogenetically related and distinct lineages in Saccharomycetales, we conclude that IAA-induced ethanol tolerance is not specific to S. cerevisiae; it may be widely detected in both pre-whole genome duplication (WGD) and post-WGD yeasts belonging to several genera of Saccharomycetales.
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Affiliation(s)
- Ruo-Ting Hsiung
- Department of Biology, National Changhua University of Education
| | - Ming-Chung Chiu
- Department of Biology, National Changhua University of Education
| | - Jui-Yu Chou
- Department of Biology, National Changhua University of Education
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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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Hou Y, Wang F, Tan Z, Cui J, Jia S. Antifungal mechanisms of ε-poly-L-Lysine with different molecular weights on Saccharomyces cerevisiae. KOREAN J CHEM ENG 2020. [DOI: 10.1007/s11814-019-0466-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Cheng HJ, Sun YH, Chang HW, Cui FF, Xue HJ, Shen YB, Wang M, Luo JM. Compatible solutes adaptive alterations in Arthrobacter simplex during exposure to ethanol, and the effect of trehalose on the stress resistance and biotransformation performance. Bioprocess Biosyst Eng 2020; 43:895-908. [PMID: 31993798 DOI: 10.1007/s00449-020-02286-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Accepted: 01/10/2020] [Indexed: 01/19/2023]
Abstract
Ethanol-tolerant Arthrobacter simplex is desirable since ethanol facilitates hydrophobic substrates dissolution on an industrial scale. Herein, alterations in compatible solutes were investigated under ethanol stress. The results showed that the amount of trehalose and glycerol increased while that of glutamate and proline decreased. The trehalose protectant role was verified and its concentration was positively related to the degree of cell tolerance. otsA, otsB and treS, three trehalose biosynthesis genes in A. simplex, also enhanced Escherichia coli stress tolerance, but the increased tolerance was dependent on the type and level of the stress. A. simplex strains accumulating trehalose showed a higher productivity in systems containing more ethanol and substrate because of better viability. The underlying mechanisms of trehalose were involved in better cell integrity, higher membrane stability, stronger reactive oxygen species scavenging capacity and higher energy level. Therefore, trehalose was a general protectant and the upregulation of its biosynthesis by genetic modification enhanced cell stress tolerance, consequently promoted productivity.
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Affiliation(s)
- Hong-Jin Cheng
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin Key Lab of Industrial Microbiology, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, 89 PO Box, No 29, St No13 Tianjin Economic-Technological Development Area (TEDA), Tianjin, 300457, People's Republic of China
| | - Ya-Hua Sun
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin Key Lab of Industrial Microbiology, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, 89 PO Box, No 29, St No13 Tianjin Economic-Technological Development Area (TEDA), Tianjin, 300457, People's Republic of China
| | - Han-Wen Chang
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin Key Lab of Industrial Microbiology, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, 89 PO Box, No 29, St No13 Tianjin Economic-Technological Development Area (TEDA), Tianjin, 300457, People's Republic of China
| | - Fang-Fang Cui
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin Key Lab of Industrial Microbiology, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, 89 PO Box, No 29, St No13 Tianjin Economic-Technological Development Area (TEDA), Tianjin, 300457, People's Republic of China
| | - Hai-Jie Xue
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin Key Lab of Industrial Microbiology, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, 89 PO Box, No 29, St No13 Tianjin Economic-Technological Development Area (TEDA), Tianjin, 300457, People's Republic of China
| | - Yan-Bing Shen
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin Key Lab of Industrial Microbiology, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, 89 PO Box, No 29, St No13 Tianjin Economic-Technological Development Area (TEDA), Tianjin, 300457, People's Republic of China
| | - Min Wang
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin Key Lab of Industrial Microbiology, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, 89 PO Box, No 29, St No13 Tianjin Economic-Technological Development Area (TEDA), Tianjin, 300457, People's Republic of China
| | - Jian-Mei Luo
- Key Laboratory of Industrial Fermentation Microbiology (Tianjin University of Science and Technology), Ministry of Education, Tianjin Key Lab of Industrial Microbiology, Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, College of Biotechnology, Tianjin University of Science and Technology, 89 PO Box, No 29, St No13 Tianjin Economic-Technological Development Area (TEDA), Tianjin, 300457, People's Republic of China. .,Ministry of Education Key Laboratory of Molecular Microbiology and Technology, Nankai University, Tianjin, 300071, People's Republic of China.
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Zhang Q, Jin YL, Fang Y, Zhao H. Adaptive evolution and selection of stress-resistant Saccharomyces cerevisiae for very high-gravity bioethanol fermentation. ELECTRON J BIOTECHN 2019. [DOI: 10.1016/j.ejbt.2019.06.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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Li XE, Wang JJ, Phornsanthia S, Yin X, Li Q. Strengthening of Cell Wall Structure Enhances Stress Resistance and Fermentation Performance in Lager Yeast. JOURNAL OF THE AMERICAN SOCIETY OF BREWING CHEMISTS 2018. [DOI: 10.1094/asbcj-2014-0320-01] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Xin-Er Li
- The Key Laboratory of Industrial Biotechnology, and Lab of Brewing Science and Technology, Ministry of Education; School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Jin-Jing Wang
- The Key Laboratory of Industrial Biotechnology, and Lab of Brewing Science and Technology, Ministry of Education; School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Supatcha Phornsanthia
- Biotechnology Department of Argo-Industry Faculty, 50 Ngamwongwan Road, Chatuchak, Bangkok 10900, Thailand
| | - Xiangsheng Yin
- Cargill Malt, McGinty Road West, MS 135, Wayzata, MN 55391
| | - Qi Li
- The Key Laboratory of Industrial Biotechnology, and Lab of Brewing Science and Technology, Ministry of Education; School of Biotechnology, Jiangnan University, Wuxi 214122, China
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Yang H, Zong X, Cui C, Mu L, Zhao H. Peptide (Lys-Leu) and amino acids (Lys and Leu) supplementations improve physiological activity and fermentation performance of brewer's yeast during very high-gravity (VHG) wort fermentation. Biotechnol Appl Biochem 2018; 65:630-638. [PMID: 29271090 DOI: 10.1002/bab.1634] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Accepted: 12/15/2017] [Indexed: 12/13/2022]
Affiliation(s)
- Huirong Yang
- School of Food Science and Engineering; South China University of Technology; Guangzhou People's Republic of China
| | - Xuyan Zong
- Liquor Making Biological Technology and Application of Key Laboratory of Sichuan Province; Sichuan University of Science and Engineering; Zigong People's Republic of China
| | - Chun Cui
- School of Food Science and Engineering; South China University of Technology; Guangzhou People's Republic of China
| | - Lixia Mu
- Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods; Ministry of Agriculture/Guangdong Key Laboratory of Agricultural Products Processing; Guangzhou People's Republic of China
| | - Haifeng Zhao
- School of Food Science and Engineering; South China University of Technology; Guangzhou People's Republic of China
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Papapetridis I, van Dijk M, van Maris AJA, Pronk JT. Metabolic engineering strategies for optimizing acetate reduction, ethanol yield and osmotolerance in S accharomyces cerevisiae. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:107. [PMID: 28450888 PMCID: PMC5406903 DOI: 10.1186/s13068-017-0791-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 04/14/2017] [Indexed: 06/01/2023]
Abstract
BACKGROUND Glycerol, whose formation contributes to cellular redox balancing and osmoregulation in Saccharomyces cerevisiae, is an important by-product of yeast-based bioethanol production. Replacing the glycerol pathway by an engineered pathway for NAD+-dependent acetate reduction has been shown to improve ethanol yields and contribute to detoxification of acetate-containing media. However, the osmosensitivity of glycerol non-producing strains limits their applicability in high-osmolarity industrial processes. This study explores engineering strategies for minimizing glycerol production by acetate-reducing strains, while retaining osmotolerance. RESULTS GPD2 encodes one of two S. cerevisiae isoenzymes of NAD+-dependent glycerol-3-phosphate dehydrogenase (G3PDH). Its deletion in an acetate-reducing strain yielded a fourfold lower glycerol production in anaerobic, low-osmolarity cultures but hardly affected glycerol production at high osmolarity. Replacement of both native G3PDHs by an archaeal NADP+-preferring enzyme, combined with deletion of ALD6, yielded an acetate-reducing strain the phenotype of which resembled that of a glycerol-negative gpd1Δ gpd2Δ strain in low-osmolarity cultures. This strain grew anaerobically at high osmolarity (1 mol L-1 glucose), while consuming acetate and producing virtually no extracellular glycerol. Its ethanol yield in high-osmolarity cultures was 13% higher than that of an acetate-reducing strain expressing the native glycerol pathway. CONCLUSIONS Deletion of GPD2 provides an attractive strategy for improving product yields of acetate-reducing S. cerevisiae strains in low, but not in high-osmolarity media. Replacement of the native yeast G3PDHs by a heterologous NADP+-preferring enzyme, combined with deletion of ALD6, virtually eliminated glycerol production in high-osmolarity cultures while enabling efficient reduction of acetate to ethanol. After further optimization of growth kinetics, this strategy for uncoupling the roles of glycerol formation in redox homeostasis and osmotolerance can be applicable for improving performance of industrial strains in high-gravity acetate-containing processes.
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Affiliation(s)
- Ioannis Papapetridis
- Industrial Microbiology Section, Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Marlous van Dijk
- Industrial Microbiology Section, Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296 Gothenburg, Sweden
| | - Antonius J. A. van Maris
- Industrial Microbiology Section, Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
- Division of Industrial Biotechnology, School of Biotechnology, KTH Royal Institute of Technology, AlbaNova University Centre, 10691 Stockholm, Sweden
| | - Jack T. Pronk
- Industrial Microbiology Section, Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
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Divate NR, Chen GH, Wang PM, Ou BR, Chung YC. Engineering Saccharomyces cerevisiae for improvement in ethanol tolerance by accumulation of trehalose. Bioengineered 2016; 7:445-458. [PMID: 27484300 DOI: 10.1080/21655979.2016.1207019] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
A genetic recombinant Saccharomyces cerevisiae starter with high ethanol tolerance capacities was constructed. In this study, the gene of trehalose-6-phosphate synthase (encoded by tps1), which catalyzes the first step in trehalose synthesis, was cloned and overexpressed in S. cerevisiae. Moreover, the gene of neutral trehalase (encoded by nth1, trehalose degrading enzyme) was deleted by using a disruption cassette, which contained long flanking homology regions of nth1 gene (the upstream 0.26 kb and downstream 0.4 kb). The engineered strain increased its tolerance against ethanol and glucose stress. The growth of the wild strain was inhibited when the medium contained 6 % or more ethanol, whereas growth of the engineered strain was affected when the medium contained 10 % or more ethanol. There was no significant difference in the ethanol yield between the wild strain and the engineered strain when the fermentation broth contained 10 % glucose (p > 0.05). The engineered strain showed greater ethanol yield than the wild type strain when the medium contained more than 15 % glucose (p < 0.05). Higher intracellular trehalose accumulation by overexpression of tps1 and deletion of nth1 might provide the ability for yeast to protect against environmental stress.
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Affiliation(s)
- Nileema R Divate
- a Department of Food and Nutrition , Providence University , Taichung , Republic of China (Taiwan)
| | - Gen-Hung Chen
- b Department of Cosmetic Science , Providence University , Taichung , Republic of China (Taiwan)
| | - Pei-Ming Wang
- a Department of Food and Nutrition , Providence University , Taichung , Republic of China (Taiwan)
| | - Bor-Rung Ou
- c Department of Animal Science and Biotechnology , Tunghai University , Taichung , Republic of China (Taiwan)
| | - Yun-Chin Chung
- a Department of Food and Nutrition , Providence University , Taichung , Republic of China (Taiwan)
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10
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Lim BR, Choi HJ, Kwon GS, Joo WH. Enhancement of solvent tolerance in Pseudomonas sp. BCNU 106 with trehalose. Lett Appl Microbiol 2015; 61:607-12. [PMID: 26433128 DOI: 10.1111/lam.12504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 09/15/2015] [Accepted: 09/24/2015] [Indexed: 11/28/2022]
Abstract
UNLABELLED As the solvent hyper-resistant Pseudomonas sp. BCNU 106 experiences limited growth with solvents, a strategy is therefore needed to allow better growth to broaden its performance in biotechnological applications. Pseudomonas sp. BCNU 106 was cultivated in a medium supplemented with 0·05 mol l(-1) trehalose, and the cell survival was observed during subsequent growth with 1% (v/v) toluene. Exogenously added trehalose was transported into the cells and conferred protection against toluene stress. BCNU 106 grown in the presence of exogenous trehalose showed higher solvent tolerance, it can thus have more potential for biotransformation and biodegradation. SIGNIFICANCE AND IMPACT OF THE STUDY This study shows that exogenously supplemented trehalose confers protection against toluene stress and enhances the bacterial cell growth in the presence of toluene. This is of importance to the mass cultivation of solvent-tolerant bacteria, where some of the growth-related limitations of solvent-tolerant bacteria can be overcome, and their performance in biotechnological applications for biotransformation and biodegradation broadened.
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Affiliation(s)
- B R Lim
- Department of Biology and Chemistry, Changwon National University, Changwon, Korea
| | - H J Choi
- Department of Biology and Chemistry, Changwon National University, Changwon, Korea
| | - G-S Kwon
- Department of Bioresource Sciences, Andong National University, Andong, Korea
| | - W H Joo
- Department of Biology and Chemistry, Changwon National University, Changwon, Korea
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Cray JA, Stevenson A, Ball P, Bankar SB, Eleutherio ECA, Ezeji TC, Singhal RS, Thevelein JM, Timson DJ, Hallsworth JE. Chaotropicity: a key factor in product tolerance of biofuel-producing microorganisms. Curr Opin Biotechnol 2015; 33:228-59. [PMID: 25841213 DOI: 10.1016/j.copbio.2015.02.010] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 02/13/2015] [Accepted: 02/18/2015] [Indexed: 10/23/2022]
Abstract
Fermentation products can chaotropically disorder macromolecular systems and induce oxidative stress, thus inhibiting biofuel production. Recently, the chaotropic activities of ethanol, butanol and vanillin have been quantified (5.93, 37.4, 174kJ kg(-1)m(-1) respectively). Use of low temperatures and/or stabilizing (kosmotropic) substances, and other approaches, can reduce, neutralize or circumvent product-chaotropicity. However, there may be limits to the alcohol concentrations that cells can tolerate; e.g. for ethanol tolerance in the most robust Saccharomyces cerevisiae strains, these are close to both the solubility limit (<25%, w/v ethanol) and the water-activity limit of the most xerotolerant strains (0.880). Nevertheless, knowledge-based strategies to mitigate or neutralize chaotropicity could lead to major improvements in rates of product formation and yields, and also therefore in the economics of biofuel production.
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Affiliation(s)
- Jonathan A Cray
- Institute for Global Food Security, School of Biological Sciences, MBC, Queen's University Belfast, Belfast BT9 7BL, Northern Ireland, UK
| | - Andrew Stevenson
- Institute for Global Food Security, School of Biological Sciences, MBC, Queen's University Belfast, Belfast BT9 7BL, Northern Ireland, UK
| | - Philip Ball
- 18 Hillcourt Road, East Dulwich, London SE22 0PE, UK
| | - Sandip B Bankar
- Department of Chemical Engineering, College of Engineering, Bharati Vidyapeeth University, Pune-Satara Road, Pune 411043, India
| | - Elis C A Eleutherio
- Universidade Federal do Rio de Janeiro, Instituto de Quimica, Programa de Pós-graduação Bioquimica, Rio de Janeiro, RJ, Brazil
| | - Thaddeus C Ezeji
- Department of Animal Sciences and Ohio Agricultural Research and Development Center (OARDC), The Ohio State University, 305 Gerlaugh Hall, 1680 Madison Avenue, Wooster, OH 44691, USA
| | - Rekha S Singhal
- Department of Food Engineering and Technology, Institute of Chemical Technology, N.P. Marg, Matunga, Mumbai, Maharashtra 400019, India
| | - Johan M Thevelein
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven and Department of Molecular Microbiology, VIB, Kasteelpark Arenberg 31, Flanders, Leuven-Heverlee B-3001, Belgium
| | - David J Timson
- Institute for Global Food Security, School of Biological Sciences, MBC, Queen's University Belfast, Belfast BT9 7BL, Northern Ireland, UK
| | - John E Hallsworth
- Institute for Global Food Security, School of Biological Sciences, MBC, Queen's University Belfast, Belfast BT9 7BL, Northern Ireland, UK.
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Feeney A, Kropp KA, O’Connor R, Sleator RD. Cronobacter sakazakii: stress survival and virulence potential in an opportunistic foodborne pathogen. Gut Microbes 2015; 5:711-8. [PMID: 25562731 PMCID: PMC4615781 DOI: 10.4161/19490976.2014.983774] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
A characteristic feature of the opportunistic foodborne pathogen Cronobacter sakazakii is its ability to survive in extremely arid environments, such as powdered infant formula, making it a dangerous opportunistic pathogen of individuals of all age groups, especially infants and neonates. Herein, we provide a brief overview of the pathogen; clinical manifestations, environmental reservoirs and our current understanding of stress response mechanisms and virulence factors which allow it to cause disease.
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Affiliation(s)
- Audrey Feeney
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland
| | - Kai A Kropp
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland
| | - Roxana O’Connor
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland
| | - Roy D Sleator
- Department of Biological Sciences; Cork Institute of Technology; Bishopstown, Cork, Ireland,Correspondence to: Roy D Sleator;
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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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Construction of lactose-consuming Saccharomyces cerevisiae for lactose fermentation into ethanol fuel. ACTA ACUST UNITED AC 2013; 40:353-63. [DOI: 10.1007/s10295-012-1227-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 12/24/2012] [Indexed: 10/27/2022]
Abstract
Abstract
Two lactose-consuming diploid Saccharomyces cerevisiae strains, AY-51024A and AY-51024M, were constructed by expressing the LAC4 and LAC12 genes of Kluyveromyces marxianus in the host strain AY-5. In AY-51024A, both genes were targeted to the ATH1 and NTH1 gene-encoding regions to abolish the activity of acid/neutral trehalase. In AY-51024M, both genes were respectively integrated into the MIG1 and NTH1 gene-encoding regions to relieve glucose repression. Physiologic studies of the two transformants under anaerobic cultivations in glucose and galactose media indicated that the expression of both LAC genes did not physiologically burden the cells, except for AY-51024A in glucose medium. Galactose consumption was initiated at higher glucose concentrations in the MIG1 deletion strain AY-51024M than in the corresponding wild-type strain and AY-51024A, wherein galactose was consumed until glucose was completely depleted in the mixture. In lactose medium, the Sp. growth rates of AY-51024A and AY-51024M under anaerobic shake-flasks were 0.025 and 0.067 h−1, respectively. The specific lactose uptake rate and ethanol production of AY-51024M were 2.50 g lactose g CDW−1 h−1 and 23.4 g l−1, respectively, whereas those of AY-51024A were 0.98 g lactose g CDW−1 h−1 and 24.3 g lactose g CDW−1 h−1, respectively. In concentrated cheese whey powder solutions, AY-51024M produced 63.3 g l−1 ethanol from approximately 150 g l−1 initial lactose in 120 h, conversely, AY-51024A consumed 63.7 % of the initial lactose and produced 35.9 g l−1 ethanol. Therefore, relieving glucose repression is an effective strategy for constructing lactose-consuming S. cerevisiae.
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Ekberg J, Rautio J, Mattinen L, Vidgren V, Londesborough J, Gibson BR. Adaptive evolution of the lager brewing yeastSaccharomyces pastorianusfor improved growth under hyperosmotic conditions and its influence on fermentation performance. FEMS Yeast Res 2013; 13:335-49. [DOI: 10.1111/1567-1364.12038] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 02/08/2013] [Accepted: 02/08/2013] [Indexed: 11/26/2022] Open
Affiliation(s)
| | | | | | - Virve Vidgren
- VTT Technical Research Centre of Finland; Espoo; Finland
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Moukamnerd C, Kawahara H, Katakura Y. Feasibility Study of Ethanol Production from Food Wastes by Consolidated Continuous Solid-State Fermentation. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/jsbs.2013.32020] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Enhancement of stress tolerance and ethanol production in Saccharomyces cerevisiae by heterologous expression of a trehalose biosynthetic gene from Streptomyces albus. BIOTECHNOL BIOPROC E 2012. [DOI: 10.1007/s12257-012-0148-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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18
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Balakumar S, Arasaratnam V. Osmo-, Thermo- and Ethanol- Tolerances of Saccharomyces cerevisiae S1. Braz J Microbiol 2012; 43:157-66. [PMID: 24031814 PMCID: PMC3768980 DOI: 10.1590/s1517-838220120001000017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 04/27/2011] [Accepted: 01/16/2012] [Indexed: 12/02/2022] Open
Abstract
Saccharomyces cerevisiae S1, which is a locally isolated and improved strain showed viability at 40, 45 and 50°C and produced ethanol at 40, 43 and 45°C. When the cells were given heat shock at 45°C for 30min and grown at 40°C, 100% viability was observed for 60h, and addition of 200gL−1 ethanol has led to complete cell death at 30h. Heat shock given at 45°C (for 30min) has improved the tolerance to temperature induced ethanol shock leading to 37% viability at 30h. When the cells were subjected to ethanol (200gL−1 for 30 min) and osmotic shock (sorbitol 300gL−1), trehalose contents in the cells were increased. The heat shocked cells showed better viability in presence of added ethanol. Soy flour supplementation has improved the viability of S. cerevisiae S1 to 80% in presence of 100gL−1 added ethanol and to 60% in presence of 300gL−1sorbitol. In presence of sorbitol (200gL−1) and ethanol (50gL−1) at 40°C, 46% viability was retained by S. cerevisiae S1 at 48h and it was improved to 80% by soy flour supplementation.
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Avrahami-Moyal L, Engelberg D, Wenger JW, Sherlock G, Braun S. Turbidostat culture of Saccharomyces cerevisiae W303-1A under selective pressure elicited by ethanol selects for mutations in SSD1 and UTH1. FEMS Yeast Res 2012; 12:521-33. [PMID: 22443114 DOI: 10.1111/j.1567-1364.2012.00803.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2011] [Revised: 03/15/2012] [Accepted: 03/17/2012] [Indexed: 11/28/2022] Open
Abstract
We investigated the genetic causes of ethanol tolerance by characterizing mutations selected in Saccharomyces cerevisiae W303-1A under the selective pressure of ethanol. W303-1A was subjected to three rounds of turbidostat, in a medium supplemented with increasing amounts of ethanol. By the end of selection, the growth rate of the culture has increased from 0.029 to 0.32 h(-1) . Unlike the progenitor strain, all yeast cells isolated from this population were able to form colonies on medium supplemented with 7% ethanol within 6 days, our definition of ethanol tolerance. Several clones selected from all three stages of selection were able to form dense colonies within 2 days on solid medium supplemented with 9% ethanol. We sequenced the whole genomes of six clones and identified mutations responsible for ethanol tolerance. Thirteen additional clones were tested for the presence of similar mutations. In 15 of 19 tolerant clones, the stop codon in ssd1-d was replaced with an amino acid-encoding codon. Three other clones contained one of two mutations in UTH1, and one clone did not contain mutations in either SSD1 or UTH1. We showed that the mutations in SSD1 and UTH1 increased tolerance of the cell wall to zymolyase and conclude that stability of the cell wall is a major factor in increased tolerance to ethanol.
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Affiliation(s)
- Liat Avrahami-Moyal
- Department of Biological Chemistry, Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
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John GSM, Gayathiri M, Rose C, Mandal AB. Osmotic Shock Augments Ethanol Stress in Saccharomyces cerevisiae MTCC 2918. Curr Microbiol 2011; 64:100-5. [DOI: 10.1007/s00284-011-0036-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Accepted: 09/23/2011] [Indexed: 11/24/2022]
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21
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Singarapu KK, Tonelli M, Chow DC, Frederick RO, Westler WM, Markley JL. Structural characterization of Hsp12, the heat shock protein from Saccharomyces cerevisiae, in aqueous solution where it is intrinsically disordered and in detergent micelles where it is locally α-helical. J Biol Chem 2011; 286:43447-53. [PMID: 21998307 PMCID: PMC3234819 DOI: 10.1074/jbc.m111.306464] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Hsp12 (heat shock protein 12) belongs to the small heat shock protein family, partially characterized as a stress response, stationary phase entry, late embryonic abundant-like protein located at the plasma membrane to protect membrane from desiccation. Here, we report the structural characterization of Hsp12 by NMR and biophysical techniques. The protein was labeled uniformly with nitrogen-15 and carbon-13 so that its conformation could be determined in detail both in aqueous solution and in two membrane-mimetic environments, SDS and dodecylphosphocholine (DPC) micelles. Secondary structural elements determined from assigned chemical shifts indicated that Hsp12 is dynamically disordered in aqueous solution, whereas it gains four helical stretches in the presence of SDS micelles and a single helix in presence of DPC. These conclusions were reinforced by circular dichroism spectra of the protein in all three environments. The lack of long range interactions in NOESY spectra indicated that the helices present in SDS micelles do not pack together. R1 and R2, relaxation and heteronuclear NOE measurements showed that the protein is disordered in aqueous solution but becomes more ordered in presence of detergent micelles. NMR spectra collected in presence of paramagnetic spin relaxation agents (5DSA, 16DSA, and Gd(DTPA-BMA)) indicated that the amphipathic α-helices of Hsp12 in SDS micelles lie on the membrane surface. These observations are in agreement with studies suggesting that Hsp12 functions to protect the membrane from desiccation.
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Affiliation(s)
- Kiran K Singarapu
- National Magnetic Resonance Facility at Madison, University of Wisconsin, Madison, Wisconsin 53705, USA
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22
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Ells TC, Truelstrup Hansen L. Increased thermal and osmotic stress resistance in Listeria monocytogenes 568 grown in the presence of trehalose due to inactivation of the phosphotrehalase-encoding gene treA. Appl Environ Microbiol 2011; 77:6841-51. [PMID: 21821737 PMCID: PMC3187093 DOI: 10.1128/aem.00757-11] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2011] [Accepted: 07/27/2011] [Indexed: 11/20/2022] Open
Abstract
The food-borne pathogen Listeria monocytogenes is a problem for food processors and consumers alike, as the organism is resistant to harsh environmental conditions and inimical barriers implemented to prevent the survival and/or growth of harmful bacteria. One mechanism by which listeriae mediate survival is through the accumulation of compatible solutes, such as proline, betaine and carnitine. In other bacteria, including Escherichia coli, the synthesis and accumulation of another compatible solute, trehalose, are known to aid in the survival of stressed cells. The objective of this research was to investigate trehalose metabolism in L. monocytogenes, where the sugar is thought to be transferred across the cytoplasmic membrane via a specific phosphoenolpyruvate phosphotransferase system and phosphorylation to trehalose-6-phosphate (T6P). The latter is subsequently broken down into glucose and glucose-6-phosphate by α,α-(1,1) phosphotrehalase, the putative product of the treA gene. Here we report on an isogenic treA mutant of L. monocytogenes 568 (568:ΔTreA) which, relative to the wild-type strain, displays increased tolerances to multiple stressors, including heat, high osmolarity, and desiccation. This is the first study to examine the putative trehalose operon in L. monocytogenes, and we demonstrate that lmo1254 (treA) in L. monocytogenes 568 indeed encodes a phosphotrehalase required for the hydrolysis of T6P. Disruption of the treA gene results in the accumulation of T6P which is subsequently dephosphorylated to trehalose in the cytosol, thereby contributing to the stress hardiness observed in the treA mutant. This study highlights the importance of compatible solutes for microbial survival in adverse environments.
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Affiliation(s)
- Timothy C Ells
- Agriculture and Agri-Food Canada, Atlantic Food and Horticulture Research Centre, 32 Main Street, Kentville, NS, Canada B4N 1J5.
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23
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Puligundla P, Poludasu RM, Rai JK, Obulam VSR. Repeated batch ethanolic fermentation of very high gravity medium by immobilized Saccharomyces cerevisiae. ANN MICROBIOL 2011. [DOI: 10.1007/s13213-011-0207-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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24
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25
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Cheng MC, Chang RC, Dent DF, Hsieh PC. Breeding an Amylolytic Yeast Strain for Alcoholic Beverage Production. Appl Biochem Biotechnol 2010; 163:693-706. [DOI: 10.1007/s12010-010-9075-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Accepted: 08/23/2010] [Indexed: 10/19/2022]
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26
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Ethanol-tolerant Saccharomyces cerevisiae strains isolated under selective conditions by over-expression of a proofreading-deficient DNA polymerase delta. J Biosci Bioeng 2010; 108:199-204. [PMID: 19664552 DOI: 10.1016/j.jbiosc.2009.03.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Revised: 03/23/2009] [Accepted: 03/24/2009] [Indexed: 11/21/2022]
Abstract
Ethanol damages the cell membrane and functional proteins, gradually reducing cell viability, and leading to cell death during fermentation which impairs effective bioethanol production by budding yeast Saccharomyces cerevisiae. To obtain more suitable strains for bioethanol production and to gain a better understanding of ethanol tolerance, ethanol-tolerant mutants were isolated using the novel mutagenesis technique based on the disparity theory of evolution. According to this theory evolution can be accelerated by affecting the lagging-strand synthesis in which DNA polymerase delta is involved. Expression of the pol3-01 gene, a proofreading-deficient of DNA polymerase delta, in S. cerevisiae W303-1A grown under conditions of increasing ethanol concentration resulted in three ethanol-tolerant mutants (YFY1, YFY2 and YFY3), which could grow in medium containing 13% ethanol. Ethanol productivity also increased in YFY strains compared to the wild-type strain in medium containing 25% glucose. Cell morphology of YFY strain cells was normal even in the presence of 8% ethanol, whereas W303-1A cells were expanded by a big vacuole. Furthermore, two of these mutants were also resistant to high-temperature, Calcofluor white and NaCl. Expression levels of TPS1 and TSL1, which are responsible for trehalose biosynthesis, were higher in YFY strains relative to W303-1A, resulting in high levels of intracellular trehalose in YFY strains. This contributed to the multiple-stress tolerance that makes YFY strains suitable for the production of bioethanol.
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27
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Ishchuk OP, Abbas CA, Sibirny AA. Heterologous expression of Saccharomyces cerevisiae MPR1 gene confers tolerance to ethanol and l-azetidine-2-carboxylic acid in Hansenula polymorpha. J Ind Microbiol Biotechnol 2009; 37:213-8. [DOI: 10.1007/s10295-009-0674-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Accepted: 11/22/2009] [Indexed: 12/01/2022]
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28
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Metabolic flux and cell cycle analysis indicating new mechanism underlying process oscillation in continuous ethanol fermentation with Saccharomyces cerevisiae under VHG conditions. Biotechnol Adv 2009; 27:1118-1123. [DOI: 10.1016/j.biotechadv.2009.05.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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29
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Araki Y, Wu H, Kitagaki H, Akao T, Takagi H, Shimoi H. Ethanol stress stimulates the Ca2+-mediated calcineurin/Crz1 pathway in Saccharomyces cerevisiae. J Biosci Bioeng 2009; 107:1-6. [PMID: 19147100 DOI: 10.1016/j.jbiosc.2008.09.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Accepted: 09/09/2008] [Indexed: 10/20/2022]
Abstract
Environmental stimuli elicit a stress response, which helps to maintain cell survival. In budding yeast Saccharomyces cerevisiae, environmental cues can activate calcineurin, a highly conserved Ca2+-- and calmodulin-dependent protein phosphatase. Calcineurin dephosphorylates the transcription factor Crz1, leading to accumulation of Crz1 in the nuclei and expression of stress responsive genes under the control of a calcineurin-dependent response element (CDRE). Ethanol is the final product of sugar fermentation by yeast, and thus a frequently encountered yeast stressor. However, adaptation of yeast to ethanol stress is poorly understood. In this study, we show that ethanol stimulates calcineurin-dependent nuclear localization of Crz1 and CDRE-dependent gene expression. Moreover, cells in which CRZ1 is deleted exhibit defective adaptation to ethanol stress, while a multicopy plasmid of CRZ1 confers an increased level of adaptive stress tolerance to ethanol. Taken together, the results indicate that ethanol activates the calcineurin/Crz1 pathway and that CRZ1 is crucial for cell survival under ethanol-induced stress.
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Affiliation(s)
- Yoshio Araki
- National Research Institute of Brewing, 3-7-1, Kagamiyama, Higashihiroshima 739-0046, Japan
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30
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Garre E, Pérez-Torrado R, Gimeno-Alcañiz JV, Matallana E. Acid trehalase is involved in intracellular trehalose mobilization during postdiauxic growth and severe saline stress inSaccharomyces cerevisiae. FEMS Yeast Res 2009; 9:52-62. [DOI: 10.1111/j.1567-1364.2008.00453.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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31
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Sanchez-Gonzalez Y, Cameleyre X, Molina-Jouve C, Goma G, Alfenore S. Dynamic microbial response under ethanol stress to monitor Saccharomyces cerevisiae activity in different initial physiological states. Bioprocess Biosyst Eng 2008; 32:459-66. [DOI: 10.1007/s00449-008-0265-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Accepted: 09/21/2008] [Indexed: 11/24/2022]
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32
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Shamrock VJ, Lindsey GG. A compensatory increase in trehalose synthesis in response to desiccation stress in Saccharomyces cerevisiae cells lacking the heat shock protein Hsp12p. Can J Microbiol 2008; 54:559-68. [PMID: 18641702 DOI: 10.1139/w08-044] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effect of HSP12 deletion on the response of yeast to desiccation was investigated. The Deltahsp12 strain was found to be more desiccation tolerant than the wild-type strain. Furthermore, the increased intracellular trehalose levels in the Deltahsp12 strain suggested that this strain compensated for the lack of Hsp12p synthesis by increasing trehalose synthesis, which facilitated increased desiccation tolerance. Results obtained from flow cytometry using the membrane exclusion dye propidium iodide suggested that Hsp12p helped maintain plasma membrane integrity during desiccation. Analysis of the oxidative loads experienced by the wild-type and Deltahsp12 strains showed that during mid-exponential phase, the increased trehalose levels present in the Deltahsp12 cells resulted in increased protection of these cells against reactive oxygen species compared with wild-type cells. During stationary phase, lower levels of reactive oxygen species reduction by reduced glutathione was enhanced in the wild-type strain, which displayed lower intracellular trehalose concentrations. Comparison of the tolerance of the wild-type and Deltahsp12 strains with applied oxidative stress showed that the Deltahsp12 strain was more tolerant to exogenously applied H2O2, which we attributed to the higher intracellular trehalose concentration. Flow cytometry demonstrated that Hsp12p played a role in maintaining plasma membrane integrity during applied oxidative stress.
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Affiliation(s)
- Vanessa J Shamrock
- Department of Molecular and Cell Biology, University of Cape Town, Private Bag 7725, Rondebosch, Cape 7700, South Africa
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33
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Mobini-Dehkordi M, Nahvi I, Zarkesh-Esfahani H, Ghaedi K, Tavassoli M, Akada R. Isolation of a novel mutant strain of Saccharomyces cerevisiae by an ethyl methane sulfonate-induced mutagenesis approach as a high producer of bioethanol. J Biosci Bioeng 2008; 105:403-8. [DOI: 10.1263/jbb.105.403] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2007] [Accepted: 01/23/2008] [Indexed: 11/17/2022]
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34
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Gibson BR, Lawrence SJ, Leclaire JPR, Powell CD, Smart KA. Yeast responses to stresses associated with industrial brewery handling: Figure 1. FEMS Microbiol Rev 2007; 31:535-69. [PMID: 17645521 DOI: 10.1111/j.1574-6976.2007.00076.x] [Citation(s) in RCA: 312] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
During brewery handling, production strains of yeast must respond to fluctuations in dissolved oxygen concentration, pH, osmolarity, ethanol concentration, nutrient supply and temperature. Fermentation performance of brewing yeast strains is dependent on their ability to adapt to these changes, particularly during batch brewery fermentation which involves the recycling (repitching) of a single yeast culture (slurry) over a number of fermentations (generations). Modern practices, such as the use of high-gravity worts and preparation of dried yeast for use as an inoculum, have increased the magnitude of the stresses to which the cell is subjected. The ability of yeast to respond effectively to these conditions is essential not only for beer production but also for maintaining the fermentation fitness of yeast for use in subsequent fermentations. During brewery handling, cells inhabit a complex environment and our understanding of stress responses under such conditions is limited. The advent of techniques capable of determining genomic and proteomic changes within the cell is likely vastly to improve our knowledge of yeast stress responses during industrial brewery handling.
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Affiliation(s)
- Brian R Gibson
- Division of Food Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, UK
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35
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Vianna CR, Silva CLC, Neves MJ, Rosa CA. Saccharomyces cerevisiae strains from traditional fermentations of Brazilian cachaça: trehalose metabolism, heat and ethanol resistance. Antonie van Leeuwenhoek 2007; 93:205-17. [PMID: 17701283 DOI: 10.1007/s10482-007-9194-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2007] [Accepted: 07/25/2007] [Indexed: 10/23/2022]
Abstract
Nine indigenous cachaça Saccharomyces cerevisiae strains and one wine strain were compared for their trehalose metabolism characteristics under non-lethal (40 degrees C) and lethal (52 degrees C) heat shock, ethanol shock and combined heat and ethanol stresses. The yeast protection mechanism was studied through trehalose concentration, neutral trehalase activity and expression of heat shock proteins Hsp70 and Hsp104. All isolates were able to accumulate trehalose and activate neutral trehalase under stress conditions. No correlation was found between trehalose levels and neutral trehalase activity under heat or ethanol shock. However, when these stresses were combined, a positive relationship was found. After pre-treatment at 40 degrees C for 60 min, and heat shock at 52 degrees C for 8 min, eight strains maintained their trehalose levels and nine strains improved their resistance against lethal heat shock. Among the investigated stresses, heat treatment induced the highest level of trehalose and combined heat and ethanol stresses activated the neutral trehalase most effectively. Hsp70 and Hsp104 were expressed by all strains at 40 degrees C and all of them survived this temperature although a decrease in cell viability was observed at 52 degrees C. The stress imposed by more than 5% ethanol (v/v) represented the best condition to differentiate strains based on trehalose levels and neutral trehalase activity. The investigated S. cerevisiae strains exhibited different characteristics of trehalose metabolism, which could be an important tool to select strains for the cachaça fermentation process.
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Affiliation(s)
- Cristina R Vianna
- Departamento de Microbiologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, C. P. 486, MG 31270-901 Brazil
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36
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Hu XH, Wang MH, Tan T, Li JR, Yang H, Leach L, Zhang RM, Luo ZW. Genetic dissection of ethanol tolerance in the budding yeast Saccharomyces cerevisiae. Genetics 2006; 175:1479-87. [PMID: 17194785 PMCID: PMC1840089 DOI: 10.1534/genetics.106.065292] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Uncovering genetic control of variation in ethanol tolerance in natural populations of yeast Saccharomyces cerevisiae is essential for understanding the evolution of fermentation, the dominant lifestyle of the species, and for improving efficiency of selection for strains with high ethanol tolerance, a character of great economic value for the brewing and biofuel industries. To date, as many as 251 genes have been predicted to be involved in influencing this character. Candidacy of these genes was determined from a tested phenotypic effect following gene knockout, from an induced change in gene function under an ethanol stress condition, or by mutagenesis. This article represents the first genomics approach for dissecting genetic variation in ethanol tolerance between two yeast strains with a highly divergent trait phenotype. We developed a simple but reliable experimental protocol for scoring the phenotype and a set of STR/SNP markers evenly covering the whole genome. We created a mapping population comprising 319 segregants from crossing the parental strains. On the basis of the data sets, we find that the tolerance trait has a high heritability and that additive genetic variance dominates genetic variation of the trait. Segregation at five QTL detected has explained approximately 50% of phenotypic variation; in particular, the major QTL mapped on yeast chromosome 9 has accounted for a quarter of the phenotypic variation. We integrated the QTL analysis with the predicted candidacy of ethanol resistance genes and found that only a few of these candidates fall in the QTL regions.
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Affiliation(s)
- X H Hu
- Laboratory of Population and Quantitative Genetics, Department of Biostatistics, State Key Laboratory of Genetic Engineering, Institute of Biomedical Sciences, School of Life Sciences, Fudan University, Shanghai 200433, China
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37
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Blieck L, Toye G, Dumortier F, Verstrepen KJ, Delvaux FR, Thevelein JM, Van Dijck P. Isolation and characterization of brewer's yeast variants with improved fermentation performance under high-gravity conditions. Appl Environ Microbiol 2006; 73:815-24. [PMID: 17158628 PMCID: PMC1800776 DOI: 10.1128/aem.02109-06] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To save energy, space, and time, today's breweries make use of high-gravity brewing in which concentrated medium (wort) is fermented, resulting in a product with higher ethanol content. After fermentation, the product is diluted to obtain beer with the desired alcohol content. While economically desirable, the use of wort with an even higher sugar concentration is limited by the inability of brewer's yeast (Saccharomyces pastorianus) to efficiently ferment such concentrated medium. Here, we describe a successful strategy to obtain yeast variants with significantly improved fermentation capacity under high-gravity conditions. We isolated better-performing variants of the industrial lager strain CMBS33 by subjecting a pool of UV-induced variants to consecutive rounds of fermentation in very-high-gravity wort (>22 degrees Plato). Two variants (GT336 and GT344) showing faster fermentation rates and/or more-complete attenuation as well as improved viability under high ethanol conditions were identified. The variants displayed the same advantages in a pilot-scale stirred fermenter under high-gravity conditions at 11 degrees C. Microarray analysis identified several genes whose altered expression may be responsible for the superior performance of the variants. The role of some of these candidate genes was confirmed by genetic transformation. Our study shows that proper selection conditions allow the isolation of variants of commercial brewer's yeast with superior fermentation characteristics. Moreover, it is the first study to identify genes that affect fermentation performance under high-gravity conditions. The results are of interest to the beer and bioethanol industries, where the use of more-concentrated medium is economically advantageous.
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Affiliation(s)
- Lies Blieck
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, Katholieke Universiteit Leuven, Belgium
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38
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Canetta E, Adya AK, Walker GM. Atomic force microscopic study of the effects of ethanol on yeast cell surface morphology. FEMS Microbiol Lett 2006; 255:308-15. [PMID: 16448511 DOI: 10.1111/j.1574-6968.2005.00089.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The detrimental effects of ethanol toxicity on the cell surface morphology of Saccharomyces cerevisiae (strain NCYC 1681) and Schizosaccharomyces pombe (strain DVPB 1354) were investigated using an atomic force microscope (AFM). In combination with culture viability and mean cell volume measurements AFM studies allowed us to relate the cell surface morphological changes, observed on nanometer lateral resolution, with the cellular stress physiology. Exposing yeasts to increasing stressful concentrations of ethanol led to decreased cell viabilities and mean cell volumes. Together with the roughness and bearing volume analyses of the AFM images, the results provided novel insight into the relative ethanol tolerance of S. cerevisiae and Sc. pombe.
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Affiliation(s)
- Elisabetta Canetta
- Condensed Matter Group and BIONTH (Bio- and Nano-Technologies for Health) Centre, School of Contemporary Sciences, University of Abertay Dundee, Dundee, Scotland, UK
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39
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Devantier R, Scheithauer B, Villas-Bôas SG, Pedersen S, Olsson L. Metabolite profiling for analysis of yeast stress response during very high gravity ethanol fermentations. Biotechnol Bioeng 2005; 90:703-14. [PMID: 15812801 DOI: 10.1002/bit.20457] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A laboratory strain and an industrial strain of Saccharomyces cerevisiae were grown at high substrate concentration, so-called very high gravity (VHG) fermentation. Simultaneous saccharification and fermentation (SSF) was applied in a batch process using 280 g/L maltodextrin as carbon source. It was shown that known ethanol and osmotic stress responses such as decreased growth rate, lower viability, higher energy consumption, and intracellular trehalose accumulation occur in VHG SSF for both strains when compared with standard laboratory medium (20 g/L glucose). The laboratory strain was the most affected. GC-MS metabolite profiling was applied for assessing the yeast stress response influence on cellular metabolism. It was found that metabolite profiles originating from different strains and/or fermentation conditions were unique and could be distinguished with the help of multivariate data analysis. Several differences in the metabolic responses to stressing conditions were revealed, particularly the increased energy consumption of stressed cells was also reflected in increased intracellular concentrations of pyruvate and related metabolites.
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Affiliation(s)
- Rasmus Devantier
- Starch, Applied Discovery, Research & Development, Novozymes A/S, Laurentsvej 51-53, DK-2880 Bagsvaerd, Denmark
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40
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Fang TY, Hung XG, Shih TY, Tseng WC. Characterization of the trehalosyl dextrin-forming enzyme from the thermophilic archaeon Sulfolobus solfataricus ATCC 35092. Extremophiles 2004; 8:335-43. [PMID: 15150700 DOI: 10.1007/s00792-004-0393-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2003] [Accepted: 04/06/2004] [Indexed: 10/26/2022]
Abstract
The trehalosyl dextrin-forming enzyme (TDFE) mainly catalyzes an intramolecular transglycosyl reaction to form trehalosyl dextrins from dextrins by converting the alpha-1,4-glucosidic linkage at the reducing end to an alpha-1,1-glucosidic linkage. In this study, the treY gene encoding TDFE was PCR cloned from the genomic DNA of Sulfolobus solfataricus ATCC 35092 to an expression vector with a T7 lac promoter and then expressed in Escherichia coli. The recombinant TDFE was purified sequentially by using heat treatment, ultrafiltration, and gel filtration. The obtained recombinant TDFE showed an apparent optimal pH of 5 and an optimal temperature of 75 degrees C. The enzyme was stable in a pH range of 4.5-11, and the activity remained unchanged after a 2-h incubation at 80 degrees C. The transglycosylation activity of TDFE was higher when using maltoheptaose as substrate than maltooligosaccharides with a low degree of polymerization (DP). However, the hydrolysis activity of TDFE became stronger when low DP maltooligosaccharides, such as maltotriose, were used as substrate. The ratios of hydrolysis activity to transglycosylation activity were in the range of 0.2-14% and increased when the DP of substrate decreased. The recombinant TDFE was found to exhibit different substrate specificity, such as its preferred substrates for the transglycosylation reaction and the ratio of hydrolysis to transglycosylation of the enzyme reacting with maltotriose, when compared with other natural or recombinant TDFEs from Sulfolobus.
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Affiliation(s)
- Tsuei-Yun Fang
- Department of Food Science, National Taiwan Ocean University, 2 Pei-Ning Rd., 202, Keelung, Taiwan.
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Suga M, Kusanagi I, Hatakeyama T. High osmotic stress improves electro-transformation efficiency of fission yeast. FEMS Microbiol Lett 2003; 225:235-9. [PMID: 12951247 DOI: 10.1016/s0378-1097(03)00518-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
A preincubation of fission yeast cells with hyperosmotic solution improved the electro-transformation efficiency. The efficiency increased approximately five-fold when the cells were preincubated with 2.0 M sorbitol and 1.5 M NaCl at 30 degrees C for 60 min before an applied high electric pulse. Losses in the efficiency of the cells after hyperosmotic stress above 2.5 M sorbitol and 2.0 M NaCl were directly related to the marked reduction of viability. The efficiency at 2.0 M sorbitol gradually increased until 60 min of the preincubation period, but longer exposure resulted in a gradual decrease. On the other hand, when the cells of the osmotic-sensitive mutant were preincubated with isosmotic solution of 0.5 M sorbitol, the efficiency was also dramatically increased by approximately 15-fold. These improvements in efficiency were observed in sublethal conditions of osmotic stress regardless of osmoticums and strains.
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Affiliation(s)
- Minoru Suga
- Department of Materials and Biosystem Engineering, Toyama University, 3190 Gofuku Toyama-City, Toyama 930-8555, Japan.
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Sampedro JG, Muñoz-Clares RA, Uribe S. Trehalose-mediated inhibition of the plasma membrane H+-ATPase from Kluyveromyces lactis: dependence on viscosity and temperature. J Bacteriol 2002; 184:4384-91. [PMID: 12142408 PMCID: PMC135241 DOI: 10.1128/jb.184.16.4384-4391.2002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The effect of increasing trehalose concentrations on the kinetics of the plasma membrane H+-ATPase from Kluyveromyces lactis was studied at different temperatures. At 20 degrees C, increasing concentrations of trehalose (0.2 to 0.8 M) decreased V(max) and increased S(0.5) (substrate concentration when initial velocity equals 0.5 V(max)), mainly at high trehalose concentrations (0.6 to 0.8 M). The quotient V(max)/S(0.5) decreased from 5.76 micromol of ATP mg of protein(-1) x min(-1) x mM(-1) in the absence of trehalose to 1.63 micromol of ATP mg of protein(-1) x min(-1) x mM(-1) in the presence of 0.8 M trehalose. The decrease in V(max) was linearly dependent on solution viscosity (eta), suggesting that inhibition was due to hindering of protein domain diffusional motion during catalysis and in accordance with Kramer's theory for reactions in solution. In this regard, two other viscosity-increasing agents, sucrose and glycerol, behaved similarly, exhibiting the same viscosity-enzyme inhibition correlation predicted. In the absence of trehalose, increasing the temperature up to 40 degrees C resulted in an exponential increase in V(max) and a decrease in enzyme cooperativity (n), while S(0.5) was not modified. As temperature increased, the effect of trehalose on V(max) decreased to become negligible at 40 degrees C, in good correlation with the temperature-mediated decrease in viscosity. The trehalose-mediated increase in S(0.5) was similar at all temperatures tested, and thus, trehalose effects on V(max)/S(0.5) were always observed. Trehalose increased the activation energy for ATP hydrolysis. Trehalose-mediated inhibition of enzymes may explain why yeast rapidly hydrolyzes trehalose when exiting heat shock.
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Affiliation(s)
- José G Sampedro
- Departamento de Bioquímica, Instituto de Fisiología Celular, Facultad de Química, Universidad Nacional Autónoma de México, 04510 Mexico City, México.
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Marza E, Camougrand N, Manon S. Bax expression protects yeast plasma membrane against ethanol-induced permeabilization. FEBS Lett 2002; 521:47-52. [PMID: 12067724 DOI: 10.1016/s0014-5793(02)02819-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The mechanism by which the expression of pro-apoptotic protein Bax is able to kill yeast was investigated. Ethanol stress induces a permeabilization of the plasma membrane revealed by propidium iodide accumulation. Bax expression, although killing yeast cells, prevents this permeabilization. These effects are modulated by aeration, by manipulation of the unsaturation index of fatty acids and by addition of resveratrol, a known inhibitor of lipid oxidation. These data suggest that lipid oxidation is involved in Bax effects. Taken together, these data show for the first time a direct effect of Bax on plasma membrane permeability properties and suggest that yeast is a powerful tool for investigating the molecular mechanisms underlying this process.
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Affiliation(s)
- Esther Marza
- UMR5095 C.N.R.S./Université de Bordeaux 2, France
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Crowe JH, Crowe LM, Oliver AE, Tsvetkova N, Wolkers W, Tablin F. The trehalose myth revisited: introduction to a symposium on stabilization of cells in the dry state. Cryobiology 2001; 43:89-105. [PMID: 11846464 DOI: 10.1006/cryo.2001.2353] [Citation(s) in RCA: 318] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This essay is an introduction to a series of papers arising from a symposium on stabilization of cells in the dry state. Nearly all of these investigations have utilized the sugar trehalose as a stabilizing molecule. Over the past two decades a myth has grown up about special properties of trehalose for stabilization of biomaterials. We review many of such uses here and show that under ideal conditions for drying and storage trehalose has few, if any, special properties. However, under suboptimal conditions trehalose has some distinct advantages and thus may remain the preferred excipient. We review the available mechanisms for introducing trehalose into the cytoplasm of living cells as an introduction to the papers that follow.
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Affiliation(s)
- J H Crowe
- Biostabilization Program, University of California, Davis, CA 95616, USA
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Lucero P, Peñalver E, Moreno E, Lagunas R. Internal trehalose protects endocytosis from inhibition by ethanol in Saccharomyces cerevisiae. Appl Environ Microbiol 2000; 66:4456-61. [PMID: 11010898 PMCID: PMC92324 DOI: 10.1128/aem.66.10.4456-4461.2000] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Endocytosis in Saccharomyces cerevisiae is inhibited by concentrations of ethanol of 2 to 6% (vol/vol), which are lower than concentrations commonly present in its natural habitats. In spite of this inhibition, endocytosis takes place under enological conditions when high concentrations of ethanol are present. Therefore, it seems that yeast has developed some means to circumvent the inhibition. In this work we have investigated this possibility. We identified two stress conditions under which endocytosis was resistant to inhibition by ethanol: fermentation during nitrogen starvation and growth on nonfermentable substrates. Under these conditions, yeast accumulates stress protectors, primarily trehalose and Hsp104, a protein required for yeast to survive ethanol stress. We found the following. (i) The appearance of ethanol resistance was accompanied by trehalose accumulation. (ii) Mutant cells unable to synthesize trehalose also were unable to develop resistance. (iii) Mutant cells that accumulated trehalose during growth on sugars were resistant to ethanol even under this nonstressing condition. (iv) Mutant cells unable to synthesize Hsp104 were able to develop resistance. We conclude that trehalose is the major factor in the protection of endocytosis from ethanol. Our results suggest another important physiological role for trehalose in yeast.
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Affiliation(s)
- P Lucero
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC, 28029-Madrid, Spain
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Accumulation of trehalose by overexpression of tps1, coding for trehalose-6-phosphate synthase, causes increased resistance to multiple stresses in the fission yeast schizosaccharomyces pombe. Appl Environ Microbiol 1999; 65:2020-4. [PMID: 10223994 PMCID: PMC91291 DOI: 10.1128/aem.65.5.2020-2024.1999] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recent studies have shown that heat shock proteins and trehalose synthesis are important factors in the thermotolerance of the fission yeast Schizosaccharomyces pombe. We examined the effects of trehalose-6-phosphate (trehalose-6P) synthase overexpression on resistance to several stresses in cells of S. pombe transformed with a plasmid bearing the tps1 gene, which codes for trehalose-6P synthase, under the control of the strong thiamine-repressible promoter. Upon induction of trehalose-6P synthase, the elevated levels of intracellular trehalose correlated not only with increased tolerance to heat shock but also with resistance to freezing and thawing, dehydration, osmostress, and toxic levels of ethanol, indicating that trehalose may be the stress metabolite underlying the overlap in induced tolerance to these stresses. Among the isogenic strains transformed with this construct, one in which the gene coding for the trehalose-hydrolyzing enzyme, neutral trehalase, was disrupted accumulated trehalose to a greater extent and was more resistant to the above stresses. Increased trehalose concentration is thus a major determinant of the general stress protection response in S. pombe.
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