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Sha Y, Ge M, Lu M, Xu Z, Zhai R, Jin M. Advances in metabolic engineering for enhanced acetyl-CoA availability in yeast. Crit Rev Biotechnol 2024:1-19. [PMID: 39266266 DOI: 10.1080/07388551.2024.2399542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2024] [Revised: 07/21/2024] [Accepted: 08/21/2024] [Indexed: 09/14/2024]
Abstract
Acetyl-CoA is an intermediate metabolite in cellular central metabolism. It's a precursor for various valuable commercial products, including: terpenoids, fatty acids, and polyketides. With the advancement of metabolic and synthetic biology tools, microbial cell factories have been constructed for the efficient synthesis of acetyl-CoA and derivatives, with the Saccharomyces cerevisiae and Yarrowia lipolytica as two prominent chassis. This review summarized the recent developments in the biosynthetic pathways and metabolic engineering approaches for acetyl-CoA and its derivatives synthesis in these two yeasts. First, the metabolic routes involved in the biosynthesis of acetyl-CoA and derived products were outlined. Then, the advancements in metabolic engineering strategies for channeling acetyl-CoA toward the desired products were summarized, with particular emphasis on: enhancing metabolic flux in different organelles, refining precursor CoA synthesis, optimizing substrate utilization, and modifying protein acetylation level. Finally, future developments in advancing the metabolic engineering strategies for acetyl-CoA and related derivatives synthesis, including: reducing CO2 emissions, dynamically regulating metabolic pathways, and exploring the regulatory functions between acetyl-CoA levels and protein acetylation, are highlighted. This review provided new insights into regulating acetyl-CoA synthesis to create more effective microbial cell factories for bio-manufacturing.
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Affiliation(s)
- Yuanyuan Sha
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, China
- Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing, China
| | - Mianshen Ge
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, China
- Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing, China
| | - Minrui Lu
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, China
- Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing, China
| | - Zhaoxian Xu
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, China
- Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing, China
| | - Rui Zhai
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, China
- Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing, China
| | - Mingjie Jin
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, China
- Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing, China
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2
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Chen Q, Chen Y, Hou Z, Ma Y, Huang J, Zhang Z, Chen Y, Yang X, Zhang Y, Zhao G. Unlocking the formate utilization of wild-type Yarrowia lipolytica through adaptive laboratory evolution. Biotechnol J 2024; 19:e2400290. [PMID: 38900053 DOI: 10.1002/biot.202400290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 05/22/2024] [Accepted: 05/28/2024] [Indexed: 06/21/2024]
Abstract
Synthetic biology is contributing to the advancement of the global net-negative carbon economy, with emphasis on formate as a member of the one-carbon substrate garnering substantial attention. In this study, we employed base editing tools to facilitate adaptive evolution, achieving a formate tolerance of Yarrowia lipolytica to 1 M within 2 months. This effort resulted in two mutant strains, designated as M25-70 and M25-14, both exhibiting significantly enhanced formate utilization capabilities. Transcriptomic analysis revealed the upregulation of nine endogenous genes encoding formate dehydrogenases when cultivated utilizing formate as the sole carbon source. Furthermore, we uncovered the pivotal role of the glyoxylate and threonine-based serine pathway in enhancing glycine supply to promote formate assimilation. The full potential of Y. lipolytica to tolerate and utilize formate establishing the foundation for pyruvate carboxylase-based carbon sequestration pathways. Importantly, this study highlights the existence of a natural formate metabolic pathway in Y. lipolytica.
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Affiliation(s)
- Qian Chen
- Tianjin University of Science & Technology, Tianjin, China
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- Haihe Laboratory of Synthetic Biology, Tianjin, China
| | - Yunhong Chen
- Tianjin University of Science & Technology, Tianjin, China
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- Haihe Laboratory of Synthetic Biology, Tianjin, China
| | - Zeming Hou
- Tianjin University of Science & Technology, Tianjin, China
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- Haihe Laboratory of Synthetic Biology, Tianjin, China
| | - Yuyue Ma
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- National Center of Technology Innovation for Synthetic Biology, Tianjin, China
| | - Jianfeng Huang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- National Center of Technology Innovation for Synthetic Biology, Tianjin, China
| | - Zhidan Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Yefu Chen
- Tianjin University of Science & Technology, Tianjin, China
| | - Xue Yang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- National Center of Technology Innovation for Synthetic Biology, Tianjin, China
| | - Yanfei Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- National Center of Technology Innovation for Synthetic Biology, Tianjin, China
| | - Guoping Zhao
- National Center of Technology Innovation for Synthetic Biology, Tianjin, China
- CAS-Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
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3
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Wu J, Huang H, Wang L, Gao M, Meng S, Zou S, Feng Y, Feng Z, Zhu Z, Cao X, Li B, Kang G. A tailored series of engineered yeasts for the cell-dependent treatment of inflammatory bowel disease by rational butyrate supplementation. Gut Microbes 2024; 16:2316575. [PMID: 38381494 PMCID: PMC10883098 DOI: 10.1080/19490976.2024.2316575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 02/06/2024] [Indexed: 02/22/2024] Open
Abstract
Intestinal microbiota dysbiosis and metabolic disruption are considered essential characteristics in inflammatory bowel disorders (IBD). Reasonable butyrate supplementation can help patients regulate intestinal flora structure and promote mucosal repair. Here, to restore microbiota homeostasis and butyrate levels in the patient's intestines, we modified the genome of Saccharomyces cerevisiae to produce butyrate. We precisely regulated the relevant metabolic pathways to enable the yeast to produce sufficient butyrate in the intestine with uneven oxygen distribution. A series of engineered strains with different butyrate synthesis abilities was constructed to meet the needs of different patients, and the strongest can reach 1.8 g/L title of butyrate. Next, this series of strains was used to co-cultivate with gut microbiota collected from patients with mild-to-moderate ulcerative colitis. After receiving treatment with engineered strains, the gut microbiota and the butyrate content have been regulated to varying degrees depending on the synthetic ability of the strain. The abundance of probiotics such as Bifidobacterium and Lactobacillus increased, while the abundance of harmful bacteria like Candidatus Bacilloplasma decreased. Meanwhile, the series of butyrate-producing yeast significantly improved trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice by restoring butyrate content. Among the series of engineered yeasts, the strain with the second-highest butyrate synthesis ability showed the most significant regulatory and the best therapeutic effect on the gut microbiota from IBD patients and the colitis mouse model. This study confirmed the existence of a therapeutic window for IBD treatment by supplementing butyrate, and it is necessary to restore butyrate levels according to the actual situation of patients to restore intestinal flora.
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Affiliation(s)
- Jiahao Wu
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - He Huang
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Lina Wang
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Mengxue Gao
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Shuxian Meng
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Shaolan Zou
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Yuanhang Feng
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Zeling Feng
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Department of Gastroenterology and Hepatology, Tianjin Medical University General Hospital, Tianjin, China
| | - Zhixin Zhu
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Xiaocang Cao
- Department of Gastroenterology and Hepatology, Tianjin Medical University General Hospital, Tianjin, China
| | - Bingzhi Li
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
| | - Guangbo Kang
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
- Frontiers Research Institute for Synthetic Biology, Tianjin University, Tianjin, China
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4
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Li Y, Hou S, Ren Z, Fu S, Wang S, Chen M, Dang Y, Li H, Li S, Li P. Transcriptomic analysis reveals hub genes and pathways in response to acetic acid stress in Kluyveromyces marxianus during high-temperature ethanol fermentation. STRESS BIOLOGY 2023; 3:26. [PMID: 37676394 PMCID: PMC10441953 DOI: 10.1007/s44154-023-00108-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 07/11/2023] [Indexed: 09/08/2023]
Abstract
The thermotolerant yeast Kluyveromyces marxianus is known for its potential in high-temperature ethanol fermentation, yet it suffers from excess acetic acid production at elevated temperatures, which hinders ethanol production. To better understand how the yeast responds to acetic acid stress during high-temperature ethanol fermentation, this study investigated its transcriptomic changes under this condition. RNA sequencing (RNA-seq) was used to identify differentially expressed genes (DEGs) and enriched gene ontology (GO) terms and pathways under acetic acid stress. The results showed that 611 genes were differentially expressed, and GO and pathway enrichment analysis revealed that acetic acid stress promoted protein catabolism but repressed protein synthesis during high-temperature fermentation. Protein-protein interaction (PPI) networks were also constructed based on the interactions between proteins coded by the DEGs. Hub genes and key modules in the PPI networks were identified, providing insight into the mechanisms of this yeast's response to acetic acid stress. The findings suggest that the decrease in ethanol production is caused by the imbalance between protein catabolism and protein synthesis. Overall, this study provides valuable insights into the mechanisms of K. marxianus's response to acetic acid stress and highlights the importance of maintaining a proper balance between protein catabolism and protein synthesis for high-temperature ethanol fermentation.
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Affiliation(s)
- Yumeng Li
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
- Engineering Research Center for Water Pollution Source Control & Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Shiqi Hou
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
- Engineering Research Center for Water Pollution Source Control & Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Ziwei Ren
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
- Engineering Research Center for Water Pollution Source Control & Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Shaojie Fu
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
- Engineering Research Center for Water Pollution Source Control & Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Sunhaoyu Wang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
- Engineering Research Center for Water Pollution Source Control & Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Mingpeng Chen
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
- Engineering Research Center for Water Pollution Source Control & Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Yan Dang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
- Engineering Research Center for Water Pollution Source Control & Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China
| | - Hongshen Li
- Institute of New Energy Technology, Tsinghua University, Beijing, 100084, China
| | - Shizhong Li
- Institute of New Energy Technology, Tsinghua University, Beijing, 100084, China
| | - Pengsong Li
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
- Engineering Research Center for Water Pollution Source Control & Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
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5
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Upadhyay V, Boorla VS, Maranas CD. Rank-ordering of known enzymes as starting points for re-engineering novel substrate activity using a convolutional neural network. Metab Eng 2023; 78:171-182. [PMID: 37301359 DOI: 10.1016/j.ymben.2023.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 05/19/2023] [Accepted: 06/02/2023] [Indexed: 06/12/2023]
Abstract
Retro-biosynthetic approaches have made significant advances in predicting synthesis routes of target biofuel, bio-renewable or bio-active molecules. The use of only cataloged enzymatic activities limits the discovery of new production routes. Recent retro-biosynthetic algorithms increasingly use novel conversions that require altering the substrate or cofactor specificities of existing enzymes while connecting pathways leading to a target metabolite. However, identifying and re-engineering enzymes for desired novel conversions are currently the bottlenecks in implementing such designed pathways. Herein, we present EnzRank, a convolutional neural network (CNN) based approach, to rank-order existing enzymes in terms of their suitability to undergo successful protein engineering through directed evolution or de novo design towards a desired specific substrate activity. We train the CNN model on 11,800 known active enzyme-substrate pairs from the BRENDA database as positive samples and data generated by scrambling these pairs as negative samples using substrate dissimilarity between an enzyme's native substrate and all other molecules present in the dataset using Tanimoto similarity score. EnzRank achieves an average recovery rate of 80.72% and 73.08% for positive and negative pairs on test data after using a 10-fold holdout method for training and cross-validation. We further developed a web-based user interface (available at https://huggingface.co/spaces/vuu10/EnzRank) to predict enzyme-substrate activity using SMILES strings of substrates and enzyme sequence as input to allow convenient and easy-to-use access to EnzRank. In summary, this effort can aid de novo pathway design tools to prioritize starting enzyme re-engineering candidates for novel reactions as well as in predicting the potential secondary activity of enzymes in cell metabolism.
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Affiliation(s)
- Vikas Upadhyay
- Department of Chemical Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Veda Sheersh Boorla
- Department of Chemical Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Costas D Maranas
- Department of Chemical Engineering, The Pennsylvania State University, University Park, PA, 16802, USA.
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6
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Glucose feeds the tricarboxylic acid cycle via excreted ethanol in fermenting yeast. Nat Chem Biol 2022; 18:1380-1387. [PMID: 35970997 DOI: 10.1038/s41589-022-01091-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 06/22/2022] [Indexed: 01/08/2023]
Abstract
Ethanol and lactate are typical waste products of glucose fermentation. In mammals, glucose is catabolized by glycolysis into circulating lactate, which is broadly used throughout the body as a carbohydrate fuel. Individual cells can both uptake and excrete lactate, uncoupling glycolysis from glucose oxidation. Here we show that similar uncoupling occurs in budding yeast batch cultures of Saccharomyces cerevisiae and Issatchenkia orientalis. Even in fermenting S. cerevisiae that is net releasing ethanol, media 13C-ethanol rapidly enters and is oxidized to acetaldehyde and acetyl-CoA. This is evident in exogenous ethanol being a major source of both cytosolic and mitochondrial acetyl units. 2H-tracing reveals that ethanol is also a major source of both NADH and NADPH high-energy electrons, and this role is augmented under oxidative stress conditions. Thus, uncoupling of glycolysis from the oxidation of glucose-derived carbon via rapidly reversible reactions is a conserved feature of eukaryotic metabolism.
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7
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Wang Y, Li W, Baker BJ, Zhou Y, He L, Danchin A, Li Q, Gao Z. Carbon metabolism and adaptation of hyperalkaliphilic microbes in serpentinizing spring of Manleluag, the Philippines. ENVIRONMENTAL MICROBIOLOGY REPORTS 2022; 14:308-319. [PMID: 35199456 DOI: 10.1111/1758-2229.13052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 02/10/2022] [Accepted: 02/11/2022] [Indexed: 06/14/2023]
Abstract
Reduced substrates produced by the serpentinization reaction under hydration of olivine may have fuelled biological processes on early Earth. To understand the adaptive strategies and carbon metabolism of the microbes in the serpentinizing ecosystems, we reconstructed 18 draft genomes representing dominant species of Omnitrophicaeota, Gammaproteobacteria and Methanobacteria from the Manleluag serpentinizing spring in Zambales, Philippines (hyperalkaline and rich in methane and hydrogen). Phylogenomics revealed that two genomes were affiliated with a candidate phylum NPL-UPA2 and the references of all our genomes were derived from ground waters, hot springs and the deep biosphere. C1 metabolism appears to be widespread as most of the genomes code for methanogenesis, CO oxidation and CO2 fixation. However, likely due to the low CO2 concentration and election acceptors, the biomass in the spring was extremely low (<103 cell/ml). Various Na+ and K+ transporters and Na+ -driving ATPases appear to be encoded by these genomes, suggesting that nutrient acquisition, bioenergetics and normal cytoplasmic pH were dependent on Na+ and K+ pumps. Our results advance our understanding of the metabolic potentials and bioenergetics of serpentinizing springs and provide a framework of the ecology of early Earth.
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Affiliation(s)
- Yong Wang
- Institute for Ocean Engineering, Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, P. R. China
| | - Wenli Li
- Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan, 572000, P. R. China
| | - Brett J Baker
- Department of Integrative Biology and Marine Science, University of Texas Austin, Austin, TX, 78373, USA
| | - Yingli Zhou
- Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan, 572000, P. R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Lisheng He
- Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan, 572000, P. R. China
| | - Antoine Danchin
- Kodikos Labs, Institut Cochin, 24 rue du Faubourg Saint Jacques, Paris, 75014, France
| | - Qingmei Li
- Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan, 572000, P. R. China
- University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Zhaoming Gao
- Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan, 572000, P. R. China
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8
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Transcriptomes analysis of Pichia kudriavzevii UniMAP 3-1 in response to acetic acid supplementation in glucose and xylose medium at elevated fermentation temperature. Process Biochem 2022. [DOI: 10.1016/j.procbio.2022.03.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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9
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Caswell BT, de Carvalho CC, Nguyen H, Roy M, Nguyen T, Cantu DC. Thioesterase enzyme families: Functions, structures, and mechanisms. Protein Sci 2022; 31:652-676. [PMID: 34921469 PMCID: PMC8862431 DOI: 10.1002/pro.4263] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 12/11/2021] [Accepted: 12/14/2021] [Indexed: 12/12/2022]
Abstract
Thioesterases are enzymes that hydrolyze thioester bonds in numerous biochemical pathways, for example in fatty acid synthesis. This work reports known functions, structures, and mechanisms of updated thioesterase enzyme families, which are classified into 35 families based on sequence similarity. Each thioesterase family is based on at least one experimentally characterized enzyme, and most families have enzymes that have been crystallized and their tertiary structure resolved. Classifying thioesterases into families allows to predict tertiary structures and infer catalytic residues and mechanisms of all sequences in a family, which is particularly useful because the majority of known protein sequence have no experimental characterization. Phylogenetic analysis of experimentally characterized thioesterases that have structures with the two main structural folds reveal convergent and divergent evolution. Based on tertiary structure superimposition, catalytic residues are predicted.
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Affiliation(s)
- Benjamin T. Caswell
- Department of Chemical and Materials EngineeringUniversity of Nevada, RenoRenoNevadaUSA
| | - Caio C. de Carvalho
- Department of Chemical and Materials EngineeringUniversity of Nevada, RenoRenoNevadaUSA
| | - Hung Nguyen
- Department of Computer Science and EngineeringUniversity of Nevada, RenoRenoNevadaUSA
| | - Monikrishna Roy
- Department of Computer Science and EngineeringUniversity of Nevada, RenoRenoNevadaUSA
| | - Tin Nguyen
- Department of Computer Science and EngineeringUniversity of Nevada, RenoRenoNevadaUSA
| | - David C. Cantu
- Department of Chemical and Materials EngineeringUniversity of Nevada, RenoRenoNevadaUSA
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10
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Hackmann TJ. Redefining the coenzyme A transferase superfamily with a large set of manually-annotated proteins. Protein Sci 2022; 31:864-881. [PMID: 35049101 PMCID: PMC8927868 DOI: 10.1002/pro.4277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 12/07/2021] [Accepted: 01/13/2022] [Indexed: 10/19/2022]
Abstract
The coenzyme A (CoA) transferases are a superfamily of proteins central to the metabolism of acetyl-CoA and other CoA thioesters. They are diverse group, catalyzing over a hundred biochemical reactions and spanning all three domains of life. A deeply rooted idea, proposed two decades ago, is these enzymes fall into three families (I, II, III). Here we find they fall into different families, which we achieve by analyzing all CoA transferases characterized to date. We manually annotated 94 CoA transferases with functional information (including rates of catalysis for 208 reactions) from 97 publications. This represents all enzymes we could find in the primary literature, and it is double the number annotated in four protein databases (BRENDA, KEGG, MetaCyc, UniProt). We found family I transferases are not closely related to each other in terms of sequence, structure, and reactions catalyzed. This family is not even monophyletic. These problems are solved by regrouping the three families into six, including one family with many non-CoA transferases. The problem (and solution) became apparent only by analyzing our large set of manually-annotated proteins. It would have been missed if we had used the small number of proteins annotated in UniProt and other databases. Our work is important to understanding the biology of CoA transferases. It also warns investigators doing phylogenetic analyses of proteins to go beyond information in databases. This article is protected by copyright. All rights reserved.
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Zhang Q, Zeng W, Xu S, Zhou J. Metabolism and strategies for enhanced supply of acetyl-CoA in Saccharomyces cerevisiae. BIORESOURCE TECHNOLOGY 2021; 342:125978. [PMID: 34598073 DOI: 10.1016/j.biortech.2021.125978] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 09/14/2021] [Accepted: 09/15/2021] [Indexed: 06/13/2023]
Abstract
Acetyl-CoA is a kind of important cofactor that is involved in many metabolic pathways. It serves as the precursor for many interesting commercial products, such as terpenes, flavonoids and anthraquinones. However, the insufficient supply of acetyl-CoA limits biosynthesis of its derived compounds in the intracellular. In this review, we outlined metabolic pathways involved in the catabolism and anabolism of acetyl-CoA, as well as some important derived products. We examined several strategies for the enhanced supply of acetyl-CoA, and provided insight into pathways that generate acetyl-CoA to balance metabolism, which can be harnessed to improve the titer, yield and productivities of interesting products in Saccharomyces cerevisiae and other eukaryotic microorganisms. We believe that peroxisomal fatty acid β-oxidation could be an attractive strategy for enhancing the supply of acetyl-CoA.
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Affiliation(s)
- Qian Zhang
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Science Center for Future Foods, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Jiangsu Provisional Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Weizhu Zeng
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Sha Xu
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Science Center for Future Foods, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Jingwen Zhou
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Science Center for Future Foods, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Jiangsu Provisional Research Center for Bioactive Product Processing Technology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China.
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12
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Jagtap SS, Deewan A, Liu JJ, Walukiewicz HE, Yun EJ, Jin YS, Rao CV. Integrating transcriptomic and metabolomic analysis of the oleaginous yeast Rhodosporidium toruloides IFO0880 during growth under different carbon sources. Appl Microbiol Biotechnol 2021; 105:7411-7425. [PMID: 34491401 DOI: 10.1007/s00253-021-11549-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 08/18/2021] [Accepted: 08/22/2021] [Indexed: 12/31/2022]
Abstract
Rhodosporidium toruloides is an oleaginous yeast capable of producing a variety of biofuels and bioproducts from diverse carbon sources. Despite numerous studies showing its promise as a platform microorganism, little is known about its metabolism and physiology. In this work, we investigated the central carbon metabolism in R. toruloides IFO0880 using transcriptomics and metabolomics during growth on glucose, xylose, acetate, or soybean oil. These substrates were chosen because they can be derived from plants. Significant changes in gene expression and metabolite concentrations were observed during growth on these four substrates. We mapped these changes onto the governing metabolic pathways to better understand how R. toruloides reprograms its metabolism to enable growth on these substrates. One notable finding concerns xylose metabolism, where poor expression of xylulokinase induces a bypass leading to arabitol production. Collectively, these results further our understanding of central carbon metabolism in R. toruloides during growth on different substrates. They may also help guide the metabolic engineering and development of better models of metabolism for R. toruloides.Key points• Gene expression and metabolite concentrations were significantly changed.• Reduced expression of xylulokinase induces a bypass leading to arabitol production.• R. toruloides reprograms its metabolism to allow growth on different substrates.
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Affiliation(s)
- Sujit Sadashiv Jagtap
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois At Urbana-Champaign, Urbana, IL, USA
- Department of Chemical and Biomolecular Engineering, University of Illinois At Urbana-Champaign, Urbana, IL, USA
| | - Anshu Deewan
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois At Urbana-Champaign, Urbana, IL, USA
- Department of Chemical and Biomolecular Engineering, University of Illinois At Urbana-Champaign, Urbana, IL, USA
| | - Jing-Jing Liu
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois At Urbana-Champaign, Urbana, IL, USA
| | - Hanna E Walukiewicz
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois At Urbana-Champaign, Urbana, IL, USA
- Department of Chemical and Biomolecular Engineering, University of Illinois At Urbana-Champaign, Urbana, IL, USA
| | - Eun Ju Yun
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois At Urbana-Champaign, Urbana, IL, USA
- Department of Biotechnology, Graduate School, Korea University, Seoul, Republic of Korea
| | - Yong-Su Jin
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois At Urbana-Champaign, Urbana, IL, USA
- Department of Food Science and Human Nutrition, University of Illinois At Urbana-Champaign, Urbana, IL, USA
| | - Christopher V Rao
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois At Urbana-Champaign, Urbana, IL, USA.
- Department of Chemical and Biomolecular Engineering, University of Illinois At Urbana-Champaign, Urbana, IL, USA.
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13
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Chen W, Yu X, Wu Y, Tang J, Yu Q, Lv X, Zha Z, Hu B, Li X, Chen J, Ma L, Workman JL, Li S. The SESAME complex regulates cell senescence through the generation of acetyl-CoA. Nat Metab 2021; 3:983-1000. [PMID: 34183849 DOI: 10.1038/s42255-021-00412-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 05/14/2021] [Indexed: 11/09/2022]
Abstract
Acetyl-CoA is a central node in carbon metabolism and plays critical roles in regulatory and biosynthetic processes. The acetyl-CoA synthetase Acs2, which catalyses acetyl-CoA production from acetate, is an integral subunit of the serine-responsive SAM-containing metabolic enzyme (SESAME) complex, but the precise function of Acs2 within the SESAME complex remains unclear. Here, using budding yeast, we show that Acs2 within the SESAME complex is required for the regulation of telomere silencing and cellular senescence. Mechanistically, the SESAME complex interacts with the histone acetyltransferase SAS protein complex to promote histone H4K16 acetylation (H4K16ac) enrichment and the occupancy of bromodomain-containing protein, Bdf1, at subtelomeric regions. This interaction maintains telomere silencing by antagonizing the spreading of Sir2 along the telomeres, which is enhanced by acetate. Consequently, dissociation of Sir2 from telomeres by acetate leads to compromised telomere silencing and accelerated chronological ageing. In human endothelial cells, ACSS2, the ortholog of yeast Acs2, also interacts with H4K16 acetyltransferase hMOF and are required for acetate to increase H4K16ac, reduce telomere silencing and induce cell senescence. Altogether, our results reveal a conserved mechanism to connect cell metabolism with telomere silencing and cellular senescence.
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Affiliation(s)
- Wanping Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Xilan Yu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Yinsheng Wu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Jie Tang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Qi Yu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Xiaodong Lv
- Human Aging Research Institute (HARI), School of Life Science, Nanchang University, Nanchang, China
| | - Zitong Zha
- Human Aging Research Institute (HARI), School of Life Science, Nanchang University, Nanchang, China
| | - Bicheng Hu
- The Central Laboratory, Wuhan No.1 Hospital, Wuhan, China
| | - Xin Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Jianguo Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Lixin Ma
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China
| | - Jerry L Workman
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Shanshan Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, China.
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Zhang B, Lingga C, Bowman C, Hackmann TJ. A New Pathway for Forming Acetate and Synthesizing ATP during Fermentation in Bacteria. Appl Environ Microbiol 2021; 87:e0295920. [PMID: 33931420 PMCID: PMC8231725 DOI: 10.1128/aem.02959-20] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 04/23/2021] [Indexed: 12/13/2022] Open
Abstract
Many bacteria and other organisms carry out fermentations forming acetate. These fermentations have broad importance for foods, agriculture, and industry. They also are important for bacteria themselves because they often generate ATP. Here, we found a biochemical pathway for forming acetate and synthesizing ATP that was unknown in fermentative bacteria. We found that the bacterium Cutibacterium granulosum formed acetate during fermentation of glucose. It did not use phosphotransacetylase or acetate kinase, enzymes found in nearly all acetate-forming bacteria. Instead, it used a pathway involving two different enzymes. The first enzyme, succinyl coenzyme A (succinyl-CoA):acetate CoA-transferase (SCACT), forms acetate from acetyl-CoA. The second enzyme, succinyl-CoA synthetase (SCS), synthesizes ATP. We identified the genes encoding these enzymes, and they were homologs of SCACT and SCS genes found in other bacteria. The pathway resembles one described in eukaryotes, but it uses bacterial, not eukaryotic, gene homologs. To find other instances of the pathway, we analyzed sequences of all biochemically characterized homologs of SCACT and SCS (103 enzymes from 64 publications). Homologs with similar enzymatic activity had similar sequences, enabling a large-scale search for them in genomes. We searched nearly 600 genomes of bacteria known to form acetate, and we found that 6% encoded homologs with SCACT and SCS activity. This included >30 species belonging to 5 different phyla, showing that a diverse range of bacteria encode the SCACT/SCS pathway. This work suggests the SCACT/SCS pathway is important for acetate formation in many branches of the tree of life. IMPORTANCE Pathways for forming acetate during fermentation have been studied for over 80 years. In that time, several pathways in a range of organisms, from bacteria to animals, have been described. However, one pathway (involving succinyl-CoA:acetate CoA-transferase and succinyl-CoA synthetase) has not been reported in prokaryotes. Here, we discovered enzymes for this pathway in the fermentative bacterium Cutibacterium granulosum. We also found >30 other fermentative bacteria that encode this pathway, demonstrating that it could be common. This pathway represents a new way for bacteria to form acetate from acetyl-CoA and synthesize ATP via substrate-level phosphorylation. It could be a target for controlling yield of acetate during fermentation, with relevance for foods, agriculture, and industry.
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Affiliation(s)
- Bo Zhang
- Department of Animal Science, University of California, Davis, California, USA
| | - Christopher Lingga
- Department of Animal Science, University of California, Davis, California, USA
| | - Courtney Bowman
- Department of Animal Sciences, University of Florida, Gainesville, Florida, USA
| | - Timothy J. Hackmann
- Department of Animal Science, University of California, Davis, California, USA
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15
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Valdetara F, Škalič M, Fracassetti D, Louw M, Compagno C, du Toit M, Foschino R, Petrovič U, Divol B, Vigentini I. Transcriptomics unravels the adaptive molecular mechanisms of Brettanomyces bruxellensis under SO2 stress in wine condition. Food Microbiol 2020; 90:103483. [DOI: 10.1016/j.fm.2020.103483] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 02/05/2020] [Accepted: 03/02/2020] [Indexed: 01/23/2023]
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Bergman A, Hellgren J, Moritz T, Siewers V, Nielsen J, Chen Y. Heterologous phosphoketolase expression redirects flux towards acetate, perturbs sugar phosphate pools and increases respiratory demand in Saccharomyces cerevisiae. Microb Cell Fact 2019; 18:25. [PMID: 30709397 PMCID: PMC6359841 DOI: 10.1186/s12934-019-1072-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 01/23/2019] [Indexed: 12/05/2022] Open
Abstract
Introduction Phosphoketolases (Xfpk) are a non-native group of enzymes in yeast, which can be expressed in combination with other metabolic enzymes to positively influence the yield of acetyl-CoA derived products by reducing carbon losses in the form of CO2. In this study, a yeast strain expressing Xfpk from Bifidobacterium breve, which was previously found to have a growth defect and to increase acetate production, was characterized. Results Xfpk-expression was found to increase respiration and reduce biomass yield during glucose consumption in batch and chemostat cultivations. By cultivating yeast with or without Xfpk in bioreactors at different pHs, we show that certain aspects of the negative growth effects coupled with Xfpk-expression are likely to be explained by proton decoupling. At low pH, this manifests as a reduction in biomass yield and growth rate in the ethanol phase. Secondly, we show that intracellular sugar phosphate pools are significantly altered in the Xfpk-expressing strain. In particular a decrease of the substrates xylulose-5-phosphate and fructose-6-phosphate was detected (26% and 74% of control levels) together with an increase of the products glyceraldehyde-3-phosphate and erythrose-4-phosphate (208% and 542% of control levels), clearly verifying in vivo Xfpk enzymatic activity. Lastly, RNAseq analysis shows that Xfpk expression increases transcription of genes related to the glyoxylate cycle, the TCA cycle and respiration, while expression of genes related to ethanol and acetate formation is reduced. The physiological and transcriptional changes clearly demonstrate that a heterologous phosphoketolase flux in combination with endogenous hydrolysis of acetyl-phosphate to acetate increases the cellular demand for acetate assimilation and respiratory ATP-generation, leading to carbon losses. Conclusion Our study shows that expression of Xfpk in yeast diverts a relatively small part of its glycolytic flux towards acetate formation, which has a significant impact on intracellular sugar phosphate levels and on cell energetics. The elevated acetate flux increases the ATP-requirement for ion homeostasis and need for respiratory assimilation, which leads to an increased production of CO2. A majority of the negative growth effects coupled to Xfpk expression could likely be counteracted by preventing acetate accumulation via direct channeling of acetyl-phosphate towards acetyl-CoA. Electronic supplementary material The online version of this article (10.1186/s12934-019-1072-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alexandra Bergman
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 41296, Gothenburg, Sweden
| | - John Hellgren
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 41296, Gothenburg, Sweden
| | - Thomas Moritz
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå Plant Science Center (UPSC), 901 83, Umeå, Sweden.,Swedish Metabolomics Centre, Umeå Plant Science Center (UPSC), 901 83, Umeå, Sweden
| | - Verena Siewers
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 41296, Gothenburg, Sweden
| | - Jens Nielsen
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 41296, Gothenburg, Sweden.,Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Yun Chen
- Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 41296, Gothenburg, Sweden. .,Novo Nordisk Foundation Center for Biosustainability, Chalmers University of Technology, 41296, Gothenburg, Sweden.
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17
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Tutaj H, Pogoda E, Tomala K, Korona R. Gene overexpression screen for chromosome instability in yeast primarily identifies cell cycle progression genes. Curr Genet 2018; 65:483-492. [PMID: 30244280 PMCID: PMC6420891 DOI: 10.1007/s00294-018-0885-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 09/11/2018] [Accepted: 09/12/2018] [Indexed: 12/12/2022]
Abstract
Loss of heterozygosity (LOH) in a vegetatively growing diploid cell signals irregularity of mitosis. Therefore, assays of LOH serve to discover pathways critical for proper replication and segregation of chromosomes. We screened for enhanced LOH in a whole-genome collection of diploid yeast strains in which a single gene was strongly overexpressed. We found 39 overexpression strains with substantially increased LOH caused either by recombination or by chromosome instability. Most of them, 32 in total, belonged to the category of "cell division", a broadly defined biological process. Of those, only one, TOP3, coded for an enzyme that uses DNA as a substrate. The rest related to establishment and maintenance of cell polarity, chromosome segregation, and cell cycle checkpoints. Former studies, in which gene deletions were used, showed that an absence of a protein participating in the DNA processing machinery is a potent stimulator of genome instability. As our results suggest, overexpression of such proteins is not comparably damaging as the absence of them. It may mean that the harmful effect of overexpression is more likely to occur in more complex and multistage processes, such as chromosome segregation. We also report a side finding, resulting from the fact that we worked with the yeast strains bearing a 2-micron plasmid. We noted that intense transcription from such a plasmid led to an enhanced rate of an entire chromosome loss (as opposed to LOH produced by recombination). This observation may support models linking segregation of 2-micron plasmids to segregation of chromosomes.
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Affiliation(s)
- Hanna Tutaj
- Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Elzbieta Pogoda
- Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Katarzyna Tomala
- Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland
| | - Ryszard Korona
- Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland.
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18
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Varland S, Aksnes H, Kryuchkov F, Impens F, Van Haver D, Jonckheere V, Ziegler M, Gevaert K, Van Damme P, Arnesen T. N-terminal Acetylation Levels Are Maintained During Acetyl-CoA Deficiency in Saccharomyces cerevisiae. Mol Cell Proteomics 2018; 17:2309-2323. [PMID: 30150368 PMCID: PMC6283290 DOI: 10.1074/mcp.ra118.000982] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 08/22/2018] [Indexed: 12/17/2022] Open
Abstract
Nt-acetylation is a prevalent protein modification catalyzed by N-terminal acetyltransferases using acetyl-CoA as acetyl donor. Here, we performed a global analysis of Nt-acetylation in yeast following nutrient starvation. Contrary to histone acetylation, which is sensitive to acetyl-CoA levels, we demonstrate that Nt-acetylation remains largely unaffected to changes in cellular metabolism. We did, however, identify two protein groups that were differentially Nt-acetylated, one showing the same sensitivity to acetyl-CoA as histones. We propose that specific, rather than global, Nt-acetylation events are subject to metabolic regulation. N-terminal acetylation (Nt-acetylation) is a highly abundant protein modification in eukaryotes and impacts a wide range of cellular processes, including protein quality control and stress tolerance. Despite its prevalence, the mechanisms regulating Nt-acetylation are still nebulous. Here, we present the first global study of Nt-acetylation in yeast cells as they progress to stationary phase in response to nutrient starvation. Surprisingly, we found that yeast cells maintain their global Nt-acetylation levels upon nutrient depletion, despite a marked decrease in acetyl-CoA levels. We further observed two distinct sets of protein N termini that display differential and opposing Nt-acetylation behavior upon nutrient starvation, indicating a dynamic process. The first protein cluster was enriched for annotated N termini showing increased Nt-acetylation in stationary phase compared with exponential growth phase. The second protein cluster was conversely enriched for alternative nonannotated N termini (i.e. N termini indicative of shorter N-terminal proteoforms) and, like histones, showed reduced acetylation levels in stationary phase when acetyl-CoA levels were low. Notably, the degree of Nt-acetylation of Pcl8, a negative regulator of glycogen biosynthesis and two components of the pre-ribosome complex (Rsa3 and Rpl7a) increased during starvation. Moreover, the steady-state levels of these proteins were regulated both by starvation and NatA activity. In summary, this study represents the first comprehensive analysis of metabolic regulation of Nt-acetylation and reveals that specific, rather than global, Nt-acetylation events are subject to metabolic regulation.
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Affiliation(s)
- Sylvia Varland
- Department of Biomedicine, University of Bergen, N-5020 Bergen, Norway; Department of Biological Sciences, University of Bergen, N-5020 Bergen, Norway; Donnelly Center for Cellular and Bio‡molecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada.
| | - Henriette Aksnes
- Department of Biomedicine, University of Bergen, N-5020 Bergen, Norway; Department of Biological Sciences, University of Bergen, N-5020 Bergen, Norway
| | - Fedor Kryuchkov
- Department of Biomedicine, University of Bergen, N-5020 Bergen, Norway
| | - Francis Impens
- VIB-UGent Center for Medical Biotechnology, B-9000 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9000 Ghent, Belgium; VIB Proteomics Core, B-9000 Ghent, Belgium
| | - Delphi Van Haver
- VIB-UGent Center for Medical Biotechnology, B-9000 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9000 Ghent, Belgium; VIB Proteomics Core, B-9000 Ghent, Belgium
| | - Veronique Jonckheere
- VIB-UGent Center for Medical Biotechnology, B-9000 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9000 Ghent, Belgium
| | - Mathias Ziegler
- Department of Biomedicine, University of Bergen, N-5020 Bergen, Norway; Department of Biological Sciences, University of Bergen, N-5020 Bergen, Norway
| | - Kris Gevaert
- VIB-UGent Center for Medical Biotechnology, B-9000 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9000 Ghent, Belgium
| | - Petra Van Damme
- Department of Biomolecular Medicine, Ghent University, B-9000 Ghent, Belgium.
| | - Thomas Arnesen
- Department of Biomedicine, University of Bergen, N-5020 Bergen, Norway; Department of Biological Sciences, University of Bergen, N-5020 Bergen, Norway; Department of Surgery, Haukeland University Hospital, N-5021 Bergen, Norway
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Baccolo G, Stamerra G, Coppola DP, Orlandi I, Vai M. Mitochondrial Metabolism and Aging in Yeast. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 340:1-33. [PMID: 30072089 DOI: 10.1016/bs.ircmb.2018.05.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Mitochondrial functionality is one of the main factors involved in cell survival, and mitochondrial dysfunctions have been identified as an aging hallmark. In particular, the insurgence of mitochondrial dysfunctions is tightly connected to mitochondrial metabolism. During aging, both mitochondrial oxidative and biosynthetic metabolisms are progressively altered, with the development of malfunctions, in turn affecting mitochondrial functionality. In this context, the relation between mitochondrial pathways and aging is evolutionarily conserved from single-celled organisms, such as yeasts, to complex multicellular organisms, such as humans. Useful information has been provided by the yeast Saccharomyces cerevisiae, which is being increasingly acknowledged as a valuable model system to uncover mechanisms underlying cellular longevity in humans. On this basis, we review the impact of specific aspects of mitochondrial metabolism on aging supported by the contributions brought by numerous studies performed employing yeast. Initially, we will focus on the tricarboxylic acid cycle and oxidative phosphorylation, describing how their modulation has consequences on cellular longevity. Afterward, we will report information regarding the importance of nicotinamide adenine dinucleotide (NAD) metabolism during aging, highlighting its relation with mitochondrial functionality. The comprehension of these key points regarding mitochondrial metabolism and their physiological importance is an essential first step for the development of therapeutic interventions that point to increase life quality during aging, therefore promoting "healthy aging," as well as lifespan itself.
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Affiliation(s)
- Giacomo Baccolo
- SYSBIO Centre for Systems Biology, Milano, Italy; Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milano, Italy
| | - Giulia Stamerra
- SYSBIO Centre for Systems Biology, Milano, Italy; Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milano, Italy
| | | | - Ivan Orlandi
- SYSBIO Centre for Systems Biology, Milano, Italy; Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milano, Italy
| | - Marina Vai
- SYSBIO Centre for Systems Biology, Milano, Italy; Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milano, Italy
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Transcriptional Profiling of Saccharomyces cerevisiae Reveals the Impact of Variation of a Single Transcription Factor on Differential Gene Expression in 4NQO, Fermentable, and Nonfermentable Carbon Sources. G3-GENES GENOMES GENETICS 2018; 8:607-619. [PMID: 29208650 PMCID: PMC5919752 DOI: 10.1534/g3.117.300138] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Cellular metabolism can change the potency of a chemical's tumorigenicity. 4-nitroquinoline-1-oxide (4NQO) is a tumorigenic drug widely used on animal models for cancer research. Polymorphisms of the transcription factor Yrr1 confer different levels of resistance to 4NQO in Saccharomyces cerevisiae To study how different Yrr1 alleles regulate gene expression leading to resistance, transcriptomes of three isogenic Scerevisiae strains carrying different Yrr1 alleles were profiled via RNA sequencing (RNA-Seq) and chromatin immunoprecipitation coupled with sequencing (ChIP-Seq) in the presence and absence of 4NQO. In response to 4NQO, all alleles of Yrr1 drove the expression of SNQ2 (a multidrug transporter), which was highest in the presence of 4NQO resistance-conferring alleles, and overexpression of SNQ2 alone was sufficient to overcome 4NQO-sensitive growth. Using shape metrics to refine the ChIP-Seq peaks, Yrr1 strongly associated with three loci including SNQ2 In addition to a known Yrr1 target SNG1, Yrr1 also bound upstream of RPL35B; however, overexpression of these genes did not confer 4NQO resistance. RNA-Seq data also implicated nucleotide synthesis pathways including the de novo purine pathway, and the ribonuclease reductase pathways were downregulated in response to 4NQO. Conversion of a 4NQO-sensitive allele to a 4NQO-resistant allele by a single point mutation mimicked the 4NQO-resistant allele in phenotype, and while the 4NQO resistant allele increased the expression of the ADE genes in the de novo purine biosynthetic pathway, the mutant Yrr1 increased expression of ADE genes even in the absence of 4NQO. These same ADE genes were only increased in the wild-type alleles in the presence of 4NQO, indicating that the point mutation activated Yrr1 to upregulate a pathway normally only activated in response to stress. The various Yrr1 alleles also influenced growth on different carbon sources by altering the function of the mitochondria. Hence, the complement to 4NQO resistance was poor growth on nonfermentable carbon sources, which in turn varied depending on the allele of Yrr1 expressed in the isogenic yeast. The oxidation state of the yeast affected the 4NQO toxicity by altering the reactive oxygen species (ROS) generated by cellular metabolism. The integration of RNA-Seq and ChIP-Seq elucidated how Yrr1 regulates global gene transcription in response to 4NQO and how various Yrr1 alleles confer differential resistance to 4NQO. This study provides guidance for further investigation into how Yrr1 regulates cellular responses to 4NQO, as well as transcriptomic resources for further analysis of transcription factor variation on carbon source utilization.
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21
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Wierman MB, Maqani N, Strickler E, Li M, Smith JS. Caloric Restriction Extends Yeast Chronological Life Span by Optimizing the Snf1 (AMPK) Signaling Pathway. Mol Cell Biol 2017; 37:e00562-16. [PMID: 28373292 PMCID: PMC5472825 DOI: 10.1128/mcb.00562-16] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 12/04/2016] [Accepted: 03/29/2017] [Indexed: 11/20/2022] Open
Abstract
AMP-activated protein kinase (AMPK) and the homologous yeast SNF1 complex are key regulators of energy metabolism that counteract nutrient deficiency and ATP depletion by phosphorylating multiple enzymes and transcription factors that maintain energetic homeostasis. AMPK/SNF1 also promotes longevity in several model organisms, including yeast. Here we investigate the role of yeast SNF1 in mediating the extension of chronological life span (CLS) by caloric restriction (CR). We find that SNF1 activity is required throughout the transition of log phase to stationary phase (diauxic shift) for effective CLS extension. CR expands the period of maximal SNF1 activation beyond the diauxic shift, as indicated by Sak1-dependent T210 phosphorylation of the Snf1 catalytic α-subunit. A concomitant increase in ADP is consistent with SNF1 activation by ADP in vivo Downstream of SNF1, the Cat8 and Adr1 transcription factors are required for full CR-induced CLS extension, implicating an alternative carbon source utilization for acetyl coenzyme A (acetyl-CoA) production and gluconeogenesis. Indeed, CR increased acetyl-CoA levels during the diauxic shift, along with expression of both acetyl-CoA synthetase genes ACS1 and ACS2 We conclude that CR maximizes Snf1 activity throughout and beyond the diauxic shift, thus optimizing the coordination of nucleocytosolic acetyl-CoA production with massive reorganization of the transcriptome and respiratory metabolism.
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Affiliation(s)
- Margaret B Wierman
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Nazif Maqani
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Erika Strickler
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Mingguang Li
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
- Department of Laboratory Medicine, Jilin Medical University, Jilin, China
| | - Jeffrey S Smith
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
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22
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Cui Z, Gao C, Li J, Hou J, Lin CSK, Qi Q. Engineering of unconventional yeast Yarrowia lipolytica for efficient succinic acid production from glycerol at low pH. Metab Eng 2017. [PMID: 28627452 DOI: 10.1016/j.ymben.2017.06.007] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Yarrowia lipolytica is considered as a potential candidate for succinic acid production because of its innate ability to accumulate citric acid cycle intermediates and its tolerance to acidic pH. Previously, a succinate-production strain was obtained through the deletion of succinate dehydrogenase subunit encoding gene Ylsdh5. However, the accumulation of by-product acetate limited further improvement of succinate production. Meanwhile, additional pH adjustment procedure increased the downstream cost in industrial application. In this study, we identified for the first time that acetic acid overflow is caused by CoA-transfer reaction from acetyl-CoA to succinate in mitochondria rather than pyruvate decarboxylation reaction in SDH negative Y. lipolytica. The deletion of CoA-transferase gene Ylach eliminated acetic acid formation and improved succinic acid production and the cell growth. We then analyzed the effect of overexpressing the key enzymes of oxidative TCA, reductive carboxylation and glyoxylate bypass on succinic acid yield and by-products formation. The best strain with phosphoenolpyruvate carboxykinase (ScPCK) from Saccharomyces cerevisiae and endogenous succinyl-CoA synthase beta subunit (YlSCS2) overexpression improved succinic acid titer by 4.3-fold. In fed-batch fermentation, this strain produced 110.7g/L succinic acid with a yield of 0.53g/g glycerol without pH control. This is the highest succinic acid titer achieved at low pH by yeast reported worldwide, to date, using defined media. This study not only revealed the mechanism of acetic acid overflow in SDH negative Y. lipolytica, but it also reported the development of an efficient succinic acid production strain with great industrial prospects.
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Affiliation(s)
- Zhiyong Cui
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China
| | - Cuijuan Gao
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China; School of Life Science, Linyi University, Linyi 276000, China
| | - Jiaojiao Li
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China
| | - Jin Hou
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China
| | - Carol Sze Ki Lin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR
| | - Qingsheng Qi
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan 250100, China.
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Improving the flux distributions simulated with genome-scale metabolic models of Saccharomyces cerevisiae. Metab Eng Commun 2016; 3:153-163. [PMID: 29468121 PMCID: PMC5779720 DOI: 10.1016/j.meteno.2016.05.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 03/17/2016] [Accepted: 05/10/2016] [Indexed: 01/23/2023] Open
Abstract
Genome-scale metabolic models (GEMs) can be used to evaluate genotype-phenotype relationships and their application to microbial strain engineering is increasing in popularity. Some of the algorithms used to simulate the phenotypes of mutant strains require the determination of a wild-type flux distribution. However, the accuracy of this reference, when calculated with flux balance analysis, has not been studied in detail before. Here, the wild-type simulations of selected GEMs for Saccharomyces cerevisiae have been analysed and most of the models tested predicted erroneous fluxes in central pathways, especially in the pentose phosphate pathway. Since the problematic fluxes were mostly related to areas of the metabolism consuming or producing NADPH/NADH, we have manually curated all reactions including these cofactors by forcing the use of NADPH/NADP+ in anabolic reactions and NADH/NAD+ for catabolic reactions. The curated models predicted more accurate flux distributions and performed better in the simulation of mutant phenotypes. The flux distributions of the genome-scale models of Saccharomyces cerevisiae were evaluated Most of the tested models showed fluxes inconsistent with experimental data A manual curation process was performed on all reactions including NADH or NADPH The curated models showed flux distributions more consistent with experimental data Phenotype simulations improved when the curated flux distributions were used
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24
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Requirements for Carnitine Shuttle-Mediated Translocation of Mitochondrial Acetyl Moieties to the Yeast Cytosol. mBio 2016; 7:mBio.00520-16. [PMID: 27143389 PMCID: PMC4959659 DOI: 10.1128/mbio.00520-16] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In many eukaryotes, the carnitine shuttle plays a key role in intracellular transport of acyl moieties. Fatty acid-grown Saccharomyces cerevisiae cells employ this shuttle to translocate acetyl units into their mitochondria. Mechanistically, the carnitine shuttle should be reversible, but previous studies indicate that carnitine shuttle-mediated export of mitochondrial acetyl units to the yeast cytosol does not occur in vivo. This apparent unidirectionality was investigated by constitutively expressing genes encoding carnitine shuttle-related proteins in an engineered S. cerevisiae strain, in which cytosolic acetyl coenzyme A (acetyl-CoA) synthesis could be switched off by omitting lipoic acid from growth media. Laboratory evolution of this strain yielded mutants whose growth on glucose, in the absence of lipoic acid, was l-carnitine dependent, indicating that in vivo export of mitochondrial acetyl units to the cytosol occurred via the carnitine shuttle. The mitochondrial pyruvate dehydrogenase complex was identified as the predominant source of acetyl-CoA in the evolved strains. Whole-genome sequencing revealed mutations in genes involved in mitochondrial fatty acid synthesis (MCT1), nuclear-mitochondrial communication (RTG2), and encoding a carnitine acetyltransferase (YAT2). Introduction of these mutations into the nonevolved parental strain enabled l-carnitine-dependent growth on glucose. This study indicates intramitochondrial acetyl-CoA concentration and constitutive expression of carnitine shuttle genes as key factors in enabling in vivo export of mitochondrial acetyl units via the carnitine shuttle. This study demonstrates, for the first time, that Saccharomyces cerevisiae can be engineered to employ the carnitine shuttle for export of acetyl moieties from the mitochondria and, thereby, to act as the sole source of cytosolic acetyl-CoA. Further optimization of this ATP-independent mechanism for cytosolic acetyl-CoA provision can contribute to efficient, yeast-based production of industrially relevant compounds derived from this precursor. The strains constructed in this study, whose growth on glucose depends on a functional carnitine shuttle, provide valuable models for further functional analysis and engineering of this shuttle in yeast and other eukaryotes.
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25
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van Rossum HM, Kozak BU, Pronk JT, van Maris AJA. Engineering cytosolic acetyl-coenzyme A supply in Saccharomyces cerevisiae: Pathway stoichiometry, free-energy conservation and redox-cofactor balancing. Metab Eng 2016; 36:99-115. [PMID: 27016336 DOI: 10.1016/j.ymben.2016.03.006] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 03/20/2016] [Accepted: 03/21/2016] [Indexed: 11/18/2022]
Abstract
Saccharomyces cerevisiae is an important industrial cell factory and an attractive experimental model for evaluating novel metabolic engineering strategies. Many current and potential products of this yeast require acetyl coenzyme A (acetyl-CoA) as a precursor and pathways towards these products are generally expressed in its cytosol. The native S. cerevisiae pathway for production of cytosolic acetyl-CoA consumes 2 ATP equivalents in the acetyl-CoA synthetase reaction. Catabolism of additional sugar substrate, which may be required to generate this ATP, negatively affects product yields. Here, we review alternative pathways that can be engineered into yeast to optimize supply of cytosolic acetyl-CoA as a precursor for product formation. Particular attention is paid to reaction stoichiometry, free-energy conservation and redox-cofactor balancing of alternative pathways for acetyl-CoA synthesis from glucose. A theoretical analysis of maximally attainable yields on glucose of four compounds (n-butanol, citric acid, palmitic acid and farnesene) showed a strong product dependency of the optimal pathway configuration for acetyl-CoA synthesis. Moreover, this analysis showed that combination of different acetyl-CoA production pathways may be required to achieve optimal product yields. This review underlines that an integral analysis of energy coupling and redox-cofactor balancing in precursor-supply and product-formation pathways is crucial for the design of efficient cell factories.
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Affiliation(s)
- Harmen M van Rossum
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - Barbara U Kozak
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - Jack T Pronk
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - Antonius J A van Maris
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
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26
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van Rossum HM, Kozak BU, Niemeijer MS, Duine HJ, Luttik MAH, Boer VM, Kötter P, Daran JMG, van Maris AJA, Pronk JT. Alternative reactions at the interface of glycolysis and citric acid cycle in Saccharomyces cerevisiae. FEMS Yeast Res 2016; 16:fow017. [PMID: 26895788 PMCID: PMC5815053 DOI: 10.1093/femsyr/fow017] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/16/2016] [Indexed: 11/14/2022] Open
Abstract
Pyruvate and acetyl-coenzyme A, located at the interface between glycolysis and TCA cycle, are important intermediates in yeast metabolism and key precursors for industrially relevant products. Rational engineering of their supply requires knowledge of compensatory reactions that replace predominant pathways when these are inactivated. This study investigates effects of individual and combined mutations that inactivate the mitochondrial pyruvate-dehydrogenase (PDH) complex, extramitochondrial citrate synthase (Cit2) and mitochondrial CoA-transferase (Ach1) in Saccharomyces cerevisiae. Additionally, strains with a constitutively expressed carnitine shuttle were constructed and analyzed. A predominant role of the PDH complex in linking glycolysis and TCA cycle in glucose-grown batch cultures could be functionally replaced by the combined activity of the cytosolic PDH bypass and Cit2. Strongly impaired growth and a high incidence of respiratory deficiency in pda1Δ ach1Δ strains showed that synthesis of intramitochondrial acetyl-CoA as a metabolic precursor requires activity of either the PDH complex or Ach1. Constitutive overexpression of AGP2, HNM1, YAT2, YAT1, CRC1 and CAT2 enabled the carnitine shuttle to efficiently link glycolysis and TCA cycle in l-carnitine-supplemented, glucose-grown batch cultures. Strains in which all known reactions at the glycolysis-TCA cycle interface were inactivated still grew slowly on glucose, indicating additional flexibility at this key metabolic junction.
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Affiliation(s)
- Harmen M van Rossum
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, NL-2628 BC Delft, The Netherlands
| | - Barbara U Kozak
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, NL-2628 BC Delft, The Netherlands
| | - Matthijs S Niemeijer
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, NL-2628 BC Delft, The Netherlands
| | - Hendrik J Duine
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, NL-2628 BC Delft, The Netherlands
| | - Marijke A H Luttik
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, NL-2628 BC Delft, The Netherlands
| | - Viktor M Boer
- DSM Biotechnology Center, Alexander Fleminglaan 1, NL-2613 AX Delft, The Netherlands
| | - Peter Kötter
- Institute for Molecular Bio Sciences, Goethe University, Max-von-Laue-Straße 9, D-60438 Frankfurt, Germany
| | - Jean-Marc G Daran
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, NL-2628 BC Delft, The Netherlands
| | - Antonius J A van Maris
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, NL-2628 BC Delft, The Netherlands
| | - Jack T Pronk
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, NL-2628 BC Delft, The Netherlands
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27
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Kozak BU, van Rossum HM, Niemeijer MS, van Dijk M, Benjamin K, Wu L, Daran JMG, Pronk JT, van Maris AJA. Replacement of the initial steps of ethanol metabolism in Saccharomyces cerevisiae by ATP-independent acetylating acetaldehyde dehydrogenase. FEMS Yeast Res 2016; 16:fow006. [PMID: 26818854 PMCID: PMC5815134 DOI: 10.1093/femsyr/fow006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 01/25/2016] [Indexed: 11/17/2022] Open
Abstract
In Saccharomyces cerevisiae ethanol dissimilation is initiated by its oxidation and activation to cytosolic acetyl-CoA. The associated consumption of ATP strongly limits yields of biomass and acetyl-CoA-derived products. Here, we explore the implementation of an ATP-independent pathway for acetyl-CoA synthesis from ethanol that, in theory, enables biomass yield on ethanol that is up to 40% higher. To this end, all native yeast acetaldehyde dehydrogenases (ALDs) were replaced by heterologous acetylating acetaldehyde dehydrogenase (A-ALD). Engineered Ald− strains expressing different A-ALDs did not immediately grow on ethanol, but serial transfer in ethanol-grown batch cultures yielded growth rates of up to 70% of the wild-type value. Mutations in ACS1 were identified in all independently evolved strains and deletion of ACS1 enabled slow growth of non-evolved Ald− A-ALD strains on ethanol. Acquired mutations in A-ALD genes improved affinity—Vmax/Km for acetaldehyde. One of five evolved strains showed a significant 5% increase of its biomass yield in ethanol-limited chemostat cultures. Increased production of acetaldehyde and other by-products was identified as possible cause for lower than theoretically predicted biomass yields. This study proves that the native yeast pathway for conversion of ethanol to acetyl-CoA can be replaced by an engineered pathway with the potential to improve biomass and product yields. This manuscript investigates a metabolic engineering strategy to improve the use of ethanol as a feedstock for production of bio-based fuels and chemicals with yeast.
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Affiliation(s)
- Barbara U Kozak
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, the Netherlands
| | - Harmen M van Rossum
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, the Netherlands
| | - Matthijs S Niemeijer
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, the Netherlands
| | - Marlous van Dijk
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, the Netherlands
| | - Kirsten Benjamin
- Amyris Inc, 5885 Hollis Street, Ste. 100, Emeryville, CA94608, USA
| | - Liang Wu
- DSM Biotechnology Center, Alexander Fleminglaan 1, 2613 AX Delft, the Netherlands
| | - Jean-Marc G Daran
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, the Netherlands
| | - Jack T Pronk
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, the Netherlands
| | - Antonius J A van Maris
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, the Netherlands
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28
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Larsson K, Istenič K, Wulff T, Jónsdóttir R, Kristinsson H, Freysdottir J, Undeland I, Jamnik P. Effect of in vitro digested cod liver oil of different quality on oxidative, proteomic and inflammatory responses in the yeast Saccharomyces cerevisiae and human monocyte-derived dendritic cells. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2015; 95:3096-3106. [PMID: 25504560 DOI: 10.1002/jsfa.7046] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 12/04/2014] [Accepted: 12/08/2014] [Indexed: 06/04/2023]
Abstract
BACKGROUND Upon oxidation of the polyunsaturated fatty acids in fish oil, either before ingestion or, as recently shown, during the gastro-intestinal passage, a cascade of potentially cytotoxic peroxidation products, such as malondialdehyde and 4-hydroxy-2-hexenal, can form. In this study, we digested fresh and oxidised cod liver oils in vitro, monitored the levels of lipid peroxidation products and evaluated oxidative, proteomic and inflammatory responses to the two types of digests in the yeast Saccharomyces cerevisiae and human monocyte-derived dendritic cells. RESULTS Digests of cod liver oil with 22-53 µmol L(-1) malondialdehyde and 0.26-3.7 µmol L(-1) 4-hydroxy-2-hexenal increased intracellular oxidation and cell energy metabolic activity compared to a digested blank in yeast cells and the influence of digests on mitochondrial protein expression was more pronounced for oxidised cod liver oil than fresh cod liver oil. The four differentially expressed and identified proteins were related to energy metabolism and oxidative stress response. Maturation of dendritic cells was affected in the presence of digested fresh cod liver oil compared to the digested blank, measured as lower CD86 expression. The ratio of secreted cytokines, IL-12p40/IL-10, suggested a pro-inflammatory effect of the digested oils in relation to the blank (1.47-1.67 vs. 1.07). CONCLUSION Gastro-intestinal digestion of cod liver oil increases the amount of oxidation products and resulting digests affect oxidation in yeast and immunomodulation of dendritic cells.
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Affiliation(s)
- Karin Larsson
- Food Science, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Katja Istenič
- Biotechnical Faculty, Department of Food Science and Technology, University of Ljubljana, Ljubljana, Slovenia
| | - Tune Wulff
- National Food Institute, Technical University of Denmark, Lyngby, Denmark
| | | | | | - Jona Freysdottir
- Department of Immunology and Centre for Rheumatology Research, Landspitali, The National University Hospital of Iceland, Reykjavik, Iceland
- Faculty of Medicine, Biomedical Center, University of Iceland, Reykjavik, Iceland
| | - Ingrid Undeland
- Food Science, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Polona Jamnik
- Biotechnical Faculty, Department of Food Science and Technology, University of Ljubljana, Ljubljana, Slovenia
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29
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Comparative proteomic analysis of engineered Saccharomyces cerevisiae with enhanced free fatty acid accumulation. Appl Microbiol Biotechnol 2015; 100:1407-1420. [PMID: 26450510 DOI: 10.1007/s00253-015-7028-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 09/13/2015] [Accepted: 09/20/2015] [Indexed: 01/27/2023]
Abstract
The engineered Saccharomyces cerevisiae strain △faa1△faa4 [Acot5s] was demonstrated to accumulate more free fatty acids (FFA) previously. Here, comparative proteomic analysis was performed to get a global overview of metabolic regulation in the strain. Over 500 proteins were identified, and 82 of those proteins were found to change significantly in the engineered strains. Proteins involved in glycolysis, acetate metabolism, fatty acid synthesis, TCA cycle, glyoxylate cycle, the pentose phosphate pathway, respiration, transportation, and stress response were found to be upregulated in △faa1△faa4 [Acot5s] as compared to the wild type. On the other hand, proteins involved in glycerol, ethanol, ergosterol, and cell wall synthesis were downregulated. Taken together with our metabolite analysis, our results showed that the disruption of Faa1 and Faa4 and expression of Acot5s in the engineered strain △faa1△faa4 [Acot5s] not only relieved the feedback inhibition of fatty acyl-CoAs on fatty acid synthesis, but also caused a major metabolic rearrangement. The rearrangement redirected carbon flux toward the pathways which generate the essential substrates and cofactors for fatty acid synthesis, such as acetyl-CoA, ATP, and NADPH. Therefore, our results help shed light on the mechanism for the increased production of fatty acids in the engineered strains, which is useful in providing information for future studies in biofuel production.
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30
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Wierman MB, Matecic M, Valsakumar V, Li M, Smith DL, Bekiranov S, Smith JS. Functional genomic analysis reveals overlapping and distinct features of chronologically long-lived yeast populations. Aging (Albany NY) 2015; 7:177-94. [PMID: 25769345 PMCID: PMC4394729 DOI: 10.18632/aging.100729] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Yeast chronological lifespan (CLS) is extended by multiple genetic and environmental manipulations, including caloric restriction (CR). Understanding the common changes in molecular pathways induced by such manipulations could potentially reveal conserved longevity mechanisms. We therefore performed gene expression profiling on several long-lived yeast populations, including an ade4∆ mutant defective in de novo purine (AMP) biosynthesis, and a calorie restricted WT strain. CLS was also extended by isonicotinamide (INAM) or expired media derived from CR cultures. Comparisons between these diverse long-lived conditions revealed a common set of differentially regulated genes, several of which were potential longevity biomarkers. There was also enrichment for genes that function in CLS regulation, including a long-lived adenosine kinase mutant (ado1∆) that links CLS regulation to the methyl cycle and AMP. Genes co-regulated between the CR and ade4∆ conditions were dominated by GO terms related to metabolism of alternative carbon sources, consistent with chronological longevity requiring efficient acetate/acetic acid utilization. Alternatively, treating cells with isonicotinamide (INAM) or the expired CR media resulted in GO terms predominantly related to cell wall remodeling, consistent with improved stress resistance and protection against external insults like acetic acid. Acetic acid therefore has both beneficial and detrimental effects on CLS.
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Affiliation(s)
- Margaret B Wierman
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Mirela Matecic
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Veena Valsakumar
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Mingguang Li
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Daniel L Smith
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL 5233, USA.,Nutrition Obesity Research Center, University of Alabama at Birmingham, Birmingham, AL 5233, USA.,Comprehensive Center for Healthy Aging, University of Alabama at Birmingham, Birmingham, AL 5233, USA
| | - Stefan Bekiranov
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Jeffrey S Smith
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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31
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Protein acetylation as a means to regulate protein function in tune with metabolic state. Biochem Soc Trans 2015; 42:1037-42. [PMID: 25109999 DOI: 10.1042/bst20140135] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Protein acetylation has emerged as a prominent post-translational modification that can occur on a wide variety of proteins. The metabolite acetyl-CoA is a key intermediate in energy metabolism that also serves as the acetyl group donor in protein acetylation modifications. Therefore such acetylation modifications might be coupled to the intracellular availability of acetyl-CoA. In the present article, we summarize recent evidence suggesting that the particular protein acetylation modifications enable the regulation of protein function in tune with acetyl-CoA availability and thus the metabolic state of the cell.
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32
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Biochemical and Kinetic Characterization of the Eukaryotic Phosphotransacetylase Class IIa Enzyme from Phytophthora ramorum. EUKARYOTIC CELL 2015; 14:652-60. [PMID: 25956919 DOI: 10.1128/ec.00007-15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 05/06/2015] [Indexed: 11/20/2022]
Abstract
Phosphotransacetylase (Pta), a key enzyme in bacterial metabolism, catalyzes the reversible transfer of an acetyl group from acetyl phosphate to coenzyme A (CoA) to produce acetyl-CoA and Pi. Two classes of Pta have been identified based on the absence (Pta(I)) or presence (Pta(II)) of an N-terminal regulatory domain. Pta(I) has been fairly well studied in bacteria and one genus of archaea; however, only the Escherichia coli and Salmonella enterica Pta(II) enzymes have been biochemically characterized, and they are allosterically regulated. Here, we describe the first biochemical and kinetic characterization of a eukaryotic Pta from the oomycete Phytophthora ramorum. The two Ptas from P. ramorum, designated PrPta(II)1 and PrPta(II)2, both belong to class II. PrPta(II)1 displayed positive cooperativity for both acetyl phosphate and CoA and is allosterically regulated. We compared the effects of different metabolites on PrPta(II)1 and the S. enterica Pta(II) and found that, although the N-terminal regulatory domains share only 19% identity, both enzymes are inhibited by ATP, NADP, NADH, phosphoenolpyruvate (PEP), and pyruvate in the acetyl-CoA/Pi-forming direction but are differentially regulated by AMP. Phylogenetic analysis of bacterial, archaeal, and eukaryotic sequences identified four subtypes of Pta(II) based on the presence or absence of the P-loop and DRTGG subdomains within the N-terminal regulatory domain. Although the E. coli, S. enterica, and P. ramorum enzymes all belong to the IIa subclass, our kinetic analysis has indicated that enzymes within a subclass can still display differences in their allosteric regulation.
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Chen Y, Zhang Y, Siewers V, Nielsen J. Ach1 is involved in shuttling mitochondrial acetyl units for cytosolic C2 provision in Saccharomyces cerevisiae lacking pyruvate decarboxylase. FEMS Yeast Res 2015; 15:fov015. [PMID: 25852051 DOI: 10.1093/femsyr/fov015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/23/2015] [Indexed: 11/14/2022] Open
Abstract
Acetyl-coenzyme A (acetyl-CoA) is not only an essential intermediate in central carbon metabolism, but also an important precursor metabolite for native or engineered pathways that can produce many products of commercial interest such as pharmaceuticals, chemicals or biofuels. In the yeast Saccharomyces cerevisiae, acetyl-CoA is compartmentalized in the cytosol, mitochondrion, peroxisome and nucleus, and cannot be directly transported between these compartments. With the acetyl-carnitine or glyoxylate shuttle, acetyl-CoA produced in peroxisomes or the cytoplasm can be transported into the cytoplasm or the mitochondria. However, whether acetyl-CoA generated in the mitochondria can be exported to the cytoplasm is still unclear. Here, we investigated whether the transfer of acetyl-CoA from the mitochondria to the cytoplasm can occur using a pyruvate decarboxylase negative, non-fermentative yeast strain. We found that mitochondrial Ach1 can convert acetyl-CoA in this compartment into acetate, which crosses the mitochondrial membrane before being converted into acetyl-CoA in the cytosol. Based on our finding we propose a model in which acetate can be used to exchange acetyl units between mitochondria and the cytosol. These results will increase our fundamental understanding of intracellular transport of acetyl units, and also help to develop microbial cell factories for many kinds of acetyl-CoA derived products.
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Affiliation(s)
- Yun Chen
- Department of Biology & Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Yiming Zhang
- Department of Biology & Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Verena Siewers
- Department of Biology & Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Jens Nielsen
- Department of Biology & Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden; Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2970 Hørsholm, Denmark
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34
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Gao J, Kim HM, Elia AE, Elledge SJ, Colaiácovo MP. NatB domain-containing CRA-1 antagonizes hydrolase ACER-1 linking acetyl-CoA metabolism to the initiation of recombination during C. elegans meiosis. PLoS Genet 2015; 11:e1005029. [PMID: 25768301 PMCID: PMC4359108 DOI: 10.1371/journal.pgen.1005029] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 01/27/2015] [Indexed: 11/18/2022] Open
Abstract
The formation of DNA double-strand breaks (DSBs) must take place during meiosis to ensure the formation of crossovers, which are required for accurate chromosome segregation, therefore avoiding aneuploidy. However, DSB formation must be tightly regulated to maintain genomic integrity. How this regulation operates in the context of different chromatin architectures and accessibility, and how it is linked to metabolic pathways, is not understood. We show here that global histone acetylation levels undergo changes throughout meiotic progression. Moreover, perturbations to global histone acetylation levels are accompanied by changes in the frequency of DSB formation in C. elegans. We provide evidence that the regulation of histone acetylation requires CRA-1, a NatB domain-containing protein homologous to human NAA25, which controls the levels of acetyl-Coenzyme A (acetyl-CoA) by antagonizing ACER-1, a previously unknown and conserved acetyl-CoA hydrolase. CRA-1 is in turn negatively regulated by XND-1, an AT-hook containing protein. We propose that this newly defined protein network links acetyl-CoA metabolism to meiotic DSB formation via modulation of global histone acetylation. Achieving accurate chromosome segregation is a critical outcome for any cell division process. Programmed DNA double-strand break formation is a central mechanism set in place to promote faithful chromosome segregation during meiosis. A subset of these DSBs is repaired as crossovers via reciprocal exchange of genetic information between homologous chromosomes resulting in physical attachments (chiasmata) between homologs, which ensure proper chromosome alignment at the metaphase plate at meiosis I, and also promote genetic diversity. How this regulation operates in the context of different chromatin architectures and accessibility, and how it is linked to metabolic pathways, is not understood. In this study, we found that CRA-1, a NatB domain-containing protein, promotes histone acetylation by maintaining the levels of acetyl-Coenzyme A (acetyl-CoA) through antagonizing ACER-1, a previously unknown and conserved acetyl-CoA hydrolase. CRA-1 is in turn negatively regulated by XND-1, an AT-hook containing protein. We leveraged this discovery to find a connection between the levels of acetyl-CoA, histone acetylation and DSB formation. We identified a novel protein network that links the regulation of DSB formation to the modulation of global levels of histone acetylation, and revealed a link between metabolism and the regulation of DSB formation.
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Affiliation(s)
- Jinmin Gao
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Hyun-Min Kim
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Andrew E. Elia
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Stephen J. Elledge
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Monica P. Colaiácovo
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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Orlandi I, Coppola DP, Vai M. Rewiring yeast acetate metabolism through MPC1 loss of function leads to mitochondrial damage and decreases chronological lifespan. ACTA ACUST UNITED AC 2014; 1:393-405. [PMID: 28357219 PMCID: PMC5349135 DOI: 10.15698/mic2014.12.178] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
During growth on fermentable substrates, such as glucose, pyruvate, which is the
end-product of glycolysis, can be used to generate acetyl-CoA in the cytosol via
acetaldehyde and acetate, or in mitochondria by direct oxidative
decarboxylation. In the latter case, the mitochondrial pyruvate carrier (MPC) is
responsible for pyruvate transport into mitochondrial matrix space. During
chronological aging, yeast cells which lack the major structural subunit Mpc1
display a reduced lifespan accompanied by an age-dependent loss of autophagy.
Here, we show that the impairment of pyruvate import into mitochondria linked to
Mpc1 loss is compensated by a flux redirection of TCA cycle intermediates
through the malic enzyme-dependent alternative route. In such a way, the TCA
cycle operates in a “branched” fashion to generate pyruvate and is depleted of
intermediates. Mutant cells cope with this depletion by increasing the activity
of glyoxylate cycle and of the pathway which provides the nucleocytosolic
acetyl-CoA. Moreover, cellular respiration decreases and ROS accumulate in the
mitochondria which, in turn, undergo severe damage. These acquired traits in
concert with the reduced autophagy restrict cell survival of the mpc1∆ mutant
during chronological aging. Conversely, the activation of the carnitine shuttle
by supplying acetyl-CoA to the mitochondria is sufficient to abrogate the
short-lived phenotype of the mutant.
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Affiliation(s)
- Ivan Orlandi
- SYSBIO Centre for Systems Biology Milano, Italy. ; Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy
| | - Damiano Pellegrino Coppola
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy
| | - Marina Vai
- SYSBIO Centre for Systems Biology Milano, Italy. ; Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy
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Kildegaard KR, Hallström BM, Blicher TH, Sonnenschein N, Jensen NB, Sherstyk S, Harrison SJ, Maury J, Herrgård MJ, Juncker AS, Forster J, Nielsen J, Borodina I. Evolution reveals a glutathione-dependent mechanism of 3-hydroxypropionic acid tolerance. Metab Eng 2014; 26:57-66. [PMID: 25263954 DOI: 10.1016/j.ymben.2014.09.004] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 08/15/2014] [Accepted: 09/15/2014] [Indexed: 12/19/2022]
Abstract
Biologically produced 3-hydroxypropionic acid (3 HP) is a potential source for sustainable acrylates and can also find direct use as monomer in the production of biodegradable polymers. For industrial-scale production there is a need for robust cell factories tolerant to high concentration of 3 HP, preferably at low pH. Through adaptive laboratory evolution we selected S. cerevisiae strains with improved tolerance to 3 HP at pH 3.5. Genome sequencing followed by functional analysis identified the causal mutation in SFA1 gene encoding S-(hydroxymethyl)glutathione dehydrogenase. Based on our findings, we propose that 3 HP toxicity is mediated by 3-hydroxypropionic aldehyde (reuterin) and that glutathione-dependent reactions are used for reuterin detoxification. The identified molecular response to 3 HP and reuterin may well be a general mechanism for handling resistance to organic acid and aldehydes by living cells.
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Affiliation(s)
- Kanchana R Kildegaard
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allé 6, DK-2970 Hørsholm, Denmark
| | - Björn M Hallström
- Science for Life Laboratory, KTH Royal Institution of Technology, Box 1031, SE-171 21 Solna, Sweden
| | - Thomas H Blicher
- The Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Blegdamsvej 3b, DK-2200 Copenhagen , Denmark
| | - Nikolaus Sonnenschein
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allé 6, DK-2970 Hørsholm, Denmark
| | - Niels B Jensen
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allé 6, DK-2970 Hørsholm, Denmark
| | - Svetlana Sherstyk
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allé 6, DK-2970 Hørsholm, Denmark
| | - Scott J Harrison
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allé 6, DK-2970 Hørsholm, Denmark
| | - Jérôme Maury
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allé 6, DK-2970 Hørsholm, Denmark
| | - Markus J Herrgård
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allé 6, DK-2970 Hørsholm, Denmark
| | - Agnieszka S Juncker
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allé 6, DK-2970 Hørsholm, Denmark
| | - Jochen Forster
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allé 6, DK-2970 Hørsholm, Denmark
| | - Jens Nielsen
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allé 6, DK-2970 Hørsholm, Denmark; Department of Chemical and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE-412 96 Göteborg, Sweden
| | - Irina Borodina
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kogle Allé 6, DK-2970 Hørsholm, Denmark.
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Hu J, Wei M, Mirzaei H, Madia F, Mirisola M, Amparo C, Chagoury S, Kennedy B, Longo VD. Tor-Sch9 deficiency activates catabolism of the ketone body-like acetic acid to promote trehalose accumulation and longevity. Aging Cell 2014; 13:457-67. [PMID: 24649827 PMCID: PMC4032597 DOI: 10.1111/acel.12202] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/02/2013] [Indexed: 11/27/2022] Open
Abstract
In mammals, extended periods of fasting leads to the accumulation of blood ketone bodies including acetoacetate. Here we show that similar to the conversion of leucine to acetoacetate in fasting mammals, starvation conditions induced ketone body-like acetic acid generation from leucine in S. cerevisiae. Whereas wild-type and ras2Δ cells accumulated acetic acid, long-lived tor1Δ and sch9Δ mutants rapidly depleted it through a mitochondrial acetate CoA transferase-dependent mechanism, which was essential for lifespan extension. The sch9Δ-dependent utilization of acetic acid also required coenzyme Q biosynthetic genes and promoted the accumulation of intracellular trehalose. These results indicate that Tor-Sch9 deficiency extends longevity by switching cells to an alternative metabolic mode, in which acetic acid can be utilized for the storage of stress resistance carbon sources. These effects are reminiscent of those described for ketone bodies in fasting mammals and raise the possibility that the lifespan extension caused by Tor-S6K inhibition may also involve analogous metabolic changes in higher eukaryotes.
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Affiliation(s)
- Jia Hu
- Longevity Institute; Davis School of Gerontology; University of Southern California; Los Angeles CA 90089 USA
- Department of Biological Sciences; School of Dornsife College of Letters, Arts and Sciences; University of Southern California; Los Angeles CA 90089 USA
| | - Min Wei
- Longevity Institute; Davis School of Gerontology; University of Southern California; Los Angeles CA 90089 USA
| | - Hamed Mirzaei
- Longevity Institute; Davis School of Gerontology; University of Southern California; Los Angeles CA 90089 USA
| | - Federica Madia
- Longevity Institute; Davis School of Gerontology; University of Southern California; Los Angeles CA 90089 USA
| | - Mario Mirisola
- Longevity Institute; Davis School of Gerontology; University of Southern California; Los Angeles CA 90089 USA
- DiBiMeF; Universita’ di Palermo; 90133 Palermo Italy
| | - Camille Amparo
- Department of Biological Sciences; School of Dornsife College of Letters, Arts and Sciences; University of Southern California; Los Angeles CA 90089 USA
| | - Shawna Chagoury
- Department of Biological Sciences; School of Dornsife College of Letters, Arts and Sciences; University of Southern California; Los Angeles CA 90089 USA
| | - Brian Kennedy
- Buck Institute for Research on Aging; Novato CA 94945 USA
| | - Valter D. Longo
- Longevity Institute; Davis School of Gerontology; University of Southern California; Los Angeles CA 90089 USA
- Department of Biological Sciences; School of Dornsife College of Letters, Arts and Sciences; University of Southern California; Los Angeles CA 90089 USA
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Bergdahl B, Gorwa-Grauslund MF, van Niel EWJ. Physiological effects of over-expressing compartment-specific components of the protein folding machinery in xylose-fermenting Saccharomyces cerevisiae. BMC Biotechnol 2014; 14:28. [PMID: 24758421 PMCID: PMC4021093 DOI: 10.1186/1472-6750-14-28] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 04/11/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Efficient utilization of both glucose and xylose is necessary for a competitive ethanol production from lignocellulosic materials. Although many advances have been made in the development of xylose-fermenting strains of Saccharomyces cerevisiae, the productivity remains much lower compared to glucose. Previous transcriptional analyses of recombinant xylose-fermenting strains have mainly focused on central carbon metabolism. Very little attention has been given to other fundamental cellular processes such as the folding of proteins. Analysis of previously measured transcript levels in a recombinant XR/XDH-strain showed a wide down-regulation of genes targeted by the unfolded protein response during xylose fermentation. Under anaerobic conditions the folding of proteins is directly connected with fumarate metabolism and requires two essential enzymes: FADH2-dependent fumarate reductase (FR) and Ero1p. In this study we tested whether these enzymes impair the protein folding process causing the very slow growth of recombinant yeast strains on xylose under anaerobic conditions. RESULTS Four strains over-expressing the cytosolic (FRD1) or mitochondrial (OSM1) FR genes and ERO1 in different combinations were constructed. The growth and fermentation performance was evaluated in defined medium as well as in a complex medium containing glucose and xylose. Over-expression of FRD1, alone or in combination with ERO1, did not have any significant effect on xylose fermentation in any medium used. Over-expression of OSM1, on the other hand, led to a diversion of carbon from glycerol to acetate and a decrease in growth rate by 39% in defined medium and by 25% in complex medium. Combined over-expression of OSM1 and ERO1 led to the same diversion of carbon from glycerol to acetate and had a stronger detrimental effect on the growth in complex medium. CONCLUSIONS Increasing the activities of the FR enzymes and Ero1p is not sufficient to increase the anaerobic growth on xylose. So additional components of the protein folding mechanism that were identified in transcription analysis of UPR related genes may also be limiting. This includes i) the transcription factor encoded by HAC1 ii) the activity of Pdi1p and iii) the requirement of free FAD during anaerobic growth.
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Affiliation(s)
- Basti Bergdahl
- Division of Applied Microbiology, Department of Chemistry, Lund University, P,O, Box 124, Lund SE-22100, Sweden.
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Nucleocytosolic depletion of the energy metabolite acetyl-coenzyme a stimulates autophagy and prolongs lifespan. Cell Metab 2014; 19:431-44. [PMID: 24606900 PMCID: PMC3988959 DOI: 10.1016/j.cmet.2014.02.010] [Citation(s) in RCA: 195] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 12/28/2013] [Accepted: 02/12/2014] [Indexed: 01/11/2023]
Abstract
Healthy aging depends on removal of damaged cellular material that is in part mediated by autophagy. The nutritional status of cells affects both aging and autophagy through as-yet-elusive metabolic circuitries. Here, we show that nucleocytosolic acetyl-coenzyme A (AcCoA) production is a metabolic repressor of autophagy during aging in yeast. Blocking the mitochondrial route to AcCoA by deletion of the CoA-transferase ACH1 caused cytosolic accumulation of the AcCoA precursor acetate. This led to hyperactivation of nucleocytosolic AcCoA-synthetase Acs2p, triggering histone acetylation, repression of autophagy genes, and an age-dependent defect in autophagic flux, culminating in a reduced lifespan. Inhibition of nutrient signaling failed to restore, while simultaneous knockdown of ACS2 reinstated, autophagy and survival of ach1 mutant. Brain-specific knockdown of Drosophila AcCoA synthetase was sufficient to enhance autophagic protein clearance and prolong lifespan. Since AcCoA integrates various nutrition pathways, our findings may explain diet-dependent lifespan and autophagy regulation.
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40
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Kozak BU, van Rossum HM, Benjamin KR, Wu L, Daran JMG, Pronk JT, van Maris AJA. Replacement of the Saccharomyces cerevisiae acetyl-CoA synthetases by alternative pathways for cytosolic acetyl-CoA synthesis. Metab Eng 2013; 21:46-59. [PMID: 24269999 DOI: 10.1016/j.ymben.2013.11.005] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 10/03/2013] [Accepted: 11/11/2013] [Indexed: 10/26/2022]
Abstract
Cytosolic acetyl-coenzyme A is a precursor for many biotechnologically relevant compounds produced by Saccharomyces cerevisiae. In this yeast, cytosolic acetyl-CoA synthesis and growth strictly depend on expression of either the Acs1 or Acs2 isoenzyme of acetyl-CoA synthetase (ACS). Since hydrolysis of ATP to AMP and pyrophosphate in the ACS reaction constrains maximum yields of acetyl-CoA-derived products, this study explores replacement of ACS by two ATP-independent pathways for acetyl-CoA synthesis. After evaluating expression of different bacterial genes encoding acetylating acetaldehyde dehydrogenase (A-ALD) and pyruvate-formate lyase (PFL), acs1Δ acs2Δ S. cerevisiae strains were constructed in which A-ALD or PFL successfully replaced ACS. In A-ALD-dependent strains, aerobic growth rates of up to 0.27 h(-1) were observed, while anaerobic growth rates of PFL-dependent S. cerevisiae (0.20 h(-1)) were stoichiometrically coupled to formate production. In glucose-limited chemostat cultures, intracellular metabolite analysis did not reveal major differences between A-ALD-dependent and reference strains. However, biomass yields on glucose of A-ALD- and PFL-dependent strains were lower than those of the reference strain. Transcriptome analysis suggested that reduced biomass yields were caused by acetaldehyde and formate in A-ALD- and PFL-dependent strains, respectively. Transcript profiles also indicated that a previously proposed role of Acs2 in histone acetylation is probably linked to cytosolic acetyl-CoA levels rather than to direct involvement of Acs2 in histone acetylation. While demonstrating that yeast ACS can be fully replaced, this study demonstrates that further modifications are needed to achieve optimal in vivo performance of the alternative reactions for supply of cytosolic acetyl-CoA as a product precursor.
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Affiliation(s)
- Barbara U Kozak
- Department of Biotechnology, Delft University of Technology, Kluyver Centre for Genomics of Industrial Fermentation, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - Harmen M van Rossum
- Department of Biotechnology, Delft University of Technology, Kluyver Centre for Genomics of Industrial Fermentation, Julianalaan 67, 2628 BC Delft, The Netherlands
| | | | - Liang Wu
- DSM Biotechnology Center, Alexander Fleminglaan 1, 2613 AX Delft, The Netherlands
| | - Jean-Marc G Daran
- Department of Biotechnology, Delft University of Technology, Kluyver Centre for Genomics of Industrial Fermentation, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - Jack T Pronk
- Department of Biotechnology, Delft University of Technology, Kluyver Centre for Genomics of Industrial Fermentation, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - Antonius J A van Maris
- Department of Biotechnology, Delft University of Technology, Kluyver Centre for Genomics of Industrial Fermentation, Julianalaan 67, 2628 BC Delft, The Netherlands.
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41
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Ethanol and acetate acting as carbon/energy sources negatively affect yeast chronological aging. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2013; 2013:802870. [PMID: 24062879 PMCID: PMC3767056 DOI: 10.1155/2013/802870] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 07/09/2013] [Indexed: 12/20/2022]
Abstract
In Saccharomyces cerevisiae, the chronological lifespan (CLS) is defined as the length of time that a population of nondividing cells can survive in stationary phase. In this phase, cells remain metabolically active, albeit at reduced levels, and responsive to environmental signals, thus simulating the postmitotic quiescent state of mammalian cells. Many studies on the main nutrient signaling pathways have uncovered the strong influence of growth conditions, including the composition of culture media, on CLS. In this context, two byproducts of yeast glucose fermentation, ethanol and acetic acid, have been proposed as extrinsic proaging factors. Here, we report that ethanol and acetic acid, at physiological levels released in the exhausted medium, both contribute to chronological aging. Moreover, this combined proaging effect is not due to a toxic environment created by their presence but is mainly mediated by the metabolic pathways required for their utilization as carbon/energy sources. In addition, measurements of key enzymatic activities of the glyoxylate cycle and gluconeogenesis, together with respiration assays performed in extreme calorie restriction, point to a long-term quiescent program favoured by glyoxylate/gluconeogenesis flux contrary to a proaging one based on the oxidative metabolism of ethanol/acetate via TCA and mitochondrial respiration.
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42
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Otzen C, Müller S, Jacobsen ID, Brock M. Phylogenetic and phenotypic characterisation of the 3-ketoacyl-CoA thiolase gene family from the opportunistic human pathogenic fungus Candida albicans. FEMS Yeast Res 2013; 13:553-64. [PMID: 23758791 DOI: 10.1111/1567-1364.12057] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 05/24/2013] [Accepted: 06/04/2013] [Indexed: 11/27/2022] Open
Abstract
Gene families are common to all kingdoms of live and most likely derived from gene duplications with subsequent specification for the adaptation to environmental conditions. However, the exact contribution of single members to cellular physiology is difficult to predict. Here, we analysed a family of 3-ketoacyl-CoA thiolases composed of Pot1p, Fox3p and Pot13p from the dimorphic yeast Candida albicans and studied their contribution to fatty acid utilisation and virulence. The presence of three 3-ketoacyl-CoA thiolases in C. albicans contrasts the existence of only one single gene in closely related Saccharomycetales such as Saccharomyces cerevisiae. Phylogenetic analyses revealed that two of the thiolases, Pot1p and Fox3p, were closely related to the S. cerevisiae Pot1p. The third protein clustered with yet uncharacterised thiolases from filamentous fungi. Single, double and triple mutants were generated for phenotypic characterisations. While Pot1p was of general importance for utilisation of fatty acids, Fox3p partially contributed to fatty acid utilisation at elevated temperatures. No phenotype was detectable for pot13 deletions. When virulence of the different mutants was assessed in an embryonated chicken egg infection model, no significant attenuation was observed for any of the mutants, confirming previous assumptions that β-oxidation is dispensable for C. albicans virulence.
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Affiliation(s)
- Christian Otzen
- Microbial Biochemistry and Physiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Jena, Germany
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García-Estrada C, Barreiro C, Jami MS, Martín-González J, Martín JF. The inducers 1,3-diaminopropane and spermidine cause the reprogramming of metabolism in Penicillium chrysogenum, leading to multiple vesicles and penicillin overproduction. J Proteomics 2013; 85:129-59. [DOI: 10.1016/j.jprot.2013.04.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 03/27/2013] [Accepted: 04/15/2013] [Indexed: 12/11/2022]
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Fazius F, Shelest E, Gebhardt P, Brock M. The fungal α-aminoadipate pathway for lysine biosynthesis requires two enzymes of the aconitase family for the isomerization of homocitrate to homoisocitrate. Mol Microbiol 2012; 86:1508-30. [PMID: 23106124 PMCID: PMC3556520 DOI: 10.1111/mmi.12076] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2012] [Indexed: 11/30/2022]
Abstract
Fungi produce α-aminoadipate, a precursor for penicillin and lysine via the α-aminoadipate pathway. Despite the biotechnological importance of this pathway, the essential isomerization of homocitrate via homoaconitate to homoisocitrate has hardly been studied. Therefore, we analysed the role of homoaconitases and aconitases in this isomerization. Although we confirmed an essential contribution of homoaconitases from Saccharomyces cerevisiae and Aspergillus fumigatus, these enzymes only catalysed the interconversion between homoaconitate and homoisocitrate. In contrast, aconitases from fungi and the thermophilic bacterium Thermus thermophilus converted homocitrate to homoaconitate. Additionally, a single aconitase appears essential for energy metabolism, glutamate and lysine biosynthesis in respirating filamentous fungi, but not in the fermenting yeast S. cerevisiae that possesses two contributing aconitases. While yeast Aco1p is essential for the citric acid cycle and, thus, for glutamate synthesis, Aco2p specifically and exclusively contributes to lysine biosynthesis. In contrast, Aco2p homologues present in filamentous fungi were transcribed, but enzymatically inactive, revealed no altered phenotype when deleted and did not complement yeast aconitase mutants. From these results we conclude that the essential requirement of filamentous fungi for respiration versus the preference of yeasts for fermentation may have directed the evolution of aconitases contributing to energy metabolism and lysine biosynthesis.
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Affiliation(s)
- Felicitas Fazius
- Microbial Biochemistry and Physiology, Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knoell-Institute, Beutenbergstr. 11a, 07745 Jena, Germany
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Son H, Min K, Lee J, Choi GJ, Kim JC, Lee YW. Mitochondrial carnitine-dependent acetyl coenzyme A transport is required for normal sexual and asexual development of the ascomycete Gibberella zeae. EUKARYOTIC CELL 2012; 11:1143-53. [PMID: 22798392 PMCID: PMC3445975 DOI: 10.1128/ec.00104-12] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 07/06/2012] [Indexed: 11/20/2022]
Abstract
Fungi have evolved efficient metabolic mechanisms for the exact temporal (developmental stages) and spatial (organelles) production of acetyl coenzyme A (acetyl-CoA). We previously demonstrated mechanistic roles of several acetyl-CoA synthetic enzymes, namely, ATP citrate lyase and acetyl-CoA synthetases (ACSs), in the plant-pathogenic fungus Gibberella zeae. In this study, we characterized two carnitine acetyltransferases (CATs; CAT1 and CAT2) to obtain a better understanding of the metabolic processes occurring in G. zeae. We found that CAT1 functioned as an alternative source of acetyl-CoA required for lipid accumulation in an ACS1 deletion mutant. Moreover, deletion of CAT1 and/or CAT2 resulted in various defects, including changes to vegetative growth, asexual/sexual development, trichothecene production, and virulence. Although CAT1 is associated primarily with peroxisomal CAT function, mislocalization experiments showed that the role of CAT1 in acetyl-CoA transport between the mitochondria and cytosol is important for sexual and asexual development in G. zeae. Taking these data together, we concluded that G. zeae CATs are responsible for facilitating the exchange of acetyl-CoA across intracellular membranes, particularly between the mitochondria and the cytosol, during various developmental stages.
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Affiliation(s)
- Hokyoung Son
- Department of Agricultural Biotechnology and Center for Fungal Pathogenesis, Seoul National University, Seoul, Republic of Korea
| | - Kyunghun Min
- Department of Agricultural Biotechnology and Center for Fungal Pathogenesis, Seoul National University, Seoul, Republic of Korea
| | - Jungkwan Lee
- Department of Applied Biology, Dong-A University, Busan, Republic of Korea
| | - Gyung Ja Choi
- Eco-Friendly New Materials Research Group, Research Center for Biobased Chemistry, Division of Convergence Chemistry, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea
| | - Jin-Cheol Kim
- Eco-Friendly New Materials Research Group, Research Center for Biobased Chemistry, Division of Convergence Chemistry, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea
| | - Yin-Won Lee
- Department of Agricultural Biotechnology and Center for Fungal Pathogenesis, Seoul National University, Seoul, Republic of Korea
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Orlandi I, Casatta N, Vai M. Lack of Ach1 CoA-Transferase Triggers Apoptosis and Decreases Chronological Lifespan in Yeast. Front Oncol 2012; 2:67. [PMID: 22754872 PMCID: PMC3386497 DOI: 10.3389/fonc.2012.00067] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 06/11/2012] [Indexed: 11/13/2022] Open
Abstract
ACH1 encodes a mitochondrial enzyme of Saccharomyces cerevisiae endowed with CoA-transferase activity. It catalyzes the CoASH transfer from succinyl-CoA to acetate generating acetyl-CoA. It is known that ACH1 inactivation results in growth defects on media containing acetate as a sole carbon and energy source which are particularly severe at low pH. Here, we show that chronological aging ach1Δ cells which accumulate a high amount of extracellular acetic acid display a reduced chronological lifespan. The faster drop of cell survival is completely abrogated by alleviating the acid stress either by a calorie restricted regimen that prevents acetic acid production or by transferring chronologically aging mutant cells to water. Moreover, the short-lived phenotype of ach1Δ cells is accompanied by reactive oxygen species accumulation, severe mitochondrial damage, and an early insurgence of apoptosis. A similar pattern of endogenous severe oxidative stress is observed when ach1Δ cells are cultured using acetic acid as a carbon source under acidic conditions. On the whole, our data provide further evidence of the role of acetic acid as cell-extrinsic mediator of cell death during chronological aging and highlight a primary role of Ach1 enzymatic activity in acetic acid detoxification which is important for mitochondrial functionality.
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Affiliation(s)
- Ivan Orlandi
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca Milano, Italy
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Cortese MS, Etxebeste O, Garzia A, Espeso EA, Ugalde U. Elucidation of functional markers from Aspergillus nidulans developmental regulator FlbB and their phylogenetic distribution. PLoS One 2011; 6:e17505. [PMID: 21423749 PMCID: PMC3053368 DOI: 10.1371/journal.pone.0017505] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Accepted: 02/06/2011] [Indexed: 11/18/2022] Open
Abstract
Aspergillus nidulans is a filamentous fungus widely used as a model for biotechnological and clinical research. It is also used as a platform for the study of basic eukaryotic developmental processes. Previous studies identified and partially characterized a set of proteins controlling cellular transformations in this ascomycete. Among these proteins, the bZip type transcription factor FlbB is a key regulator of reproduction, stress responses and cell-death. Our aim here was the prediction, through various bioinformatic methods, of key functional residues and motifs within FlbB in order to inform the design of future laboratory experiments and further the understanding of the molecular mechanisms that control fungal development. A dataset of FlbB orthologs and those of its key interaction partner FlbE was assembled from 40 members of the Pezizomycotina. Unique features were identified in each of the three structural domains of FlbB. The N-terminal region encoded a bZip transcription factor domain with a novel histidine-containing DNA binding motif while the dimerization determinants exhibited two distinct profiles that segregated by class. The C-terminal region of FlbB showed high similarity with the AP-1 family of stress response regulators but with variable patterns of conserved cysteines that segregated by class and order. Motif conservation analysis revealed that nine FlbB orthologs belonging to the Eurotiales order contained a motif in the central region that could mediate interaction with FlbE. The key residues and motifs identified here provide a basis for the design of follow-up experimental investigations. Additionally, the presence or absence of these residues and motifs among the FlbB orthologs could help explain the differences in the developmental programs among fungal species as well as define putative complementation groups that could serve to extend known functional characterizations to other species.
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Affiliation(s)
- Marc S Cortese
- Department of Applied Chemistry, Faculty of Chemistry, University of the Basque Country, San Sebastián, Spain.
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Role of carnitine acetyltransferases in acetyl coenzyme A metabolism in Aspergillus nidulans. EUKARYOTIC CELL 2011; 10:547-55. [PMID: 21296915 DOI: 10.1128/ec.00295-10] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The flow of carbon metabolites between cellular compartments is an essential feature of fungal metabolism. During growth on ethanol, acetate, or fatty acids, acetyl units must enter the mitochondrion for metabolism via the tricarboxylic acid cycle, and acetyl coenzyme A (acetyl-CoA) in the cytoplasm is essential for the biosynthetic reactions and for protein acetylation. Acetyl-CoA is produced in the cytoplasm by acetyl-CoA synthetase during growth on acetate and ethanol while β-oxidation of fatty acids generates acetyl-CoA in peroxisomes. The acetyl-carnitine shuttle in which acetyl-CoA is reversibly converted to acetyl-carnitine by carnitine acetyltransferase (CAT) enzymes is important for intracellular transport of acetyl units. In the filamentous ascomycete Aspergillus nidulans, a cytoplasmic CAT, encoded by facC, is essential for growth on sources of cytoplasmic acetyl-CoA while a second CAT, encoded by the acuJ gene, is essential for growth on fatty acids as well as acetate. We have shown that AcuJ contains an N-terminal mitochondrial targeting sequence and a C-terminal peroxisomal targeting sequence (PTS) and is localized to both peroxisomes and mitochondria, independent of the carbon source. Mislocalization of AcuJ to the cytoplasm does not result in loss of growth on acetate but prevents growth on fatty acids. Therefore, while mitochondrial AcuJ is essential for the transfer of acetyl units to mitochondria, peroxisomal localization is required only for transfer from peroxisomes to mitochondria. Peroxisomal AcuJ was not required for the import of acetyl-CoA into peroxisomes for conversion to malate by malate synthase (MLS), and export of acetyl-CoA from peroxisomes to the cytoplasm was found to be independent of FacC when MLS was mislocalized to the cytoplasm.
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Intracellular acetyl unit transport in fungal carbon metabolism. EUKARYOTIC CELL 2010; 9:1809-15. [PMID: 20889721 DOI: 10.1128/ec.00172-10] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Acetyl coenzyme A (acetyl-CoA) is a central metabolite in carbon and energy metabolism. Because of its amphiphilic nature and bulkiness, acetyl-CoA cannot readily traverse biological membranes. In fungi, two systems for acetyl unit transport have been identified: a shuttle dependent on the carrier carnitine and a (peroxisomal) citrate synthase-dependent pathway. In the carnitine-dependent pathway, carnitine acetyltransferases exchange the CoA group of acetyl-CoA for carnitine, thereby forming acetyl-carnitine, which can be transported between subcellular compartments. Citrate synthase catalyzes the condensation of oxaloacetate and acetyl-CoA to form citrate that can be transported over the membrane. Since essential metabolic pathways such as fatty acid β-oxidation, the tricarboxylic acid (TCA) cycle, and the glyoxylate cycle are physically separated into different organelles, shuttling of acetyl units is essential for growth of fungal species on various carbon sources such as fatty acids, ethanol, acetate, or citrate. In this review we summarize the current knowledge on the different systems of acetyl transport that are operational during alternative carbon metabolism, with special focus on two fungal species: Saccharomyces cerevisiae and Candida albicans.
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Cantu DC, Chen Y, Reilly PJ. Thioesterases: a new perspective based on their primary and tertiary structures. Protein Sci 2010; 19:1281-95. [PMID: 20506386 DOI: 10.1002/pro.417] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Thioesterases (TEs) are classified into EC 3.1.2.1 through EC 3.1.2.27 based on their activities on different substrates, with many remaining unclassified (EC 3.1.2.-). Analysis of primary and tertiary structures of known TEs casts a new light on this enzyme group. We used strong primary sequence conservation based on experimentally proved proteins as the main criterion, followed by verification with tertiary structure superpositions, mechanisms, and catalytic residue positions, to accurately define TE families. At present, TEs fall into 23 families almost completely unrelated to each other by primary structure. It is assumed that all members of the same family have essentially the same tertiary structure; however, TEs in different families can have markedly different folds and mechanisms. Conversely, the latter sometimes have very similar tertiary structures and catalytic mechanisms despite being only slightly or not at all related by primary structure, indicating that they have common distant ancestors and can be grouped into clans. At present, four clans encompass 12 TE families. The new constantly updated ThYme (Thioester-active enzYmes) database contains TE primary and tertiary structures, classified into families and clans that are different from those currently found in the literature or in other databases. We review all types of TEs, including those cleaving CoA, ACP, glutathione, and other protein molecules, and we discuss their structures, functions, and mechanisms.
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Affiliation(s)
- David C Cantu
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, USA
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