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Whitaker-Lockwood JA, Scholten SK, Karim F, Luiten AN, Perrella C. Comb spectroscopy of CO 2 produced from microbial metabolism. BIOMEDICAL OPTICS EXPRESS 2024; 15:1553-1570. [PMID: 38495728 PMCID: PMC10942673 DOI: 10.1364/boe.515988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 01/26/2024] [Accepted: 01/30/2024] [Indexed: 03/19/2024]
Abstract
We have developed a direct frequency comb spectroscopy instrument, which we have tested on Saccharomyces cerevisiae (baker's yeast) by measuring its CO2 output and production rate as we varied the environmental conditions, including the amount and type of feed sugar, the temperature, and the amount of yeast. By feeding isotopically-enhanced sugar to the yeast, we demonstrate the capability of our device to differentiate between two isotopologues of CO2, with a concentration measurement precision of 260 ppm for 12C16O2 and 175 ppm for 13C16O2. We also demonstrate the ability of our spectrometer to measure the proportion of carbon in the feed sugar converted to CO2, and estimate the amount incorporated into the yeast biomass.
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Affiliation(s)
- Joshua A Whitaker-Lockwood
- Institute for Photonics and Advanced Sensing, School of Physical Sciences, University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Sarah K Scholten
- Institute for Photonics and Advanced Sensing, School of Physical Sciences, University of Adelaide, Adelaide, South Australia, 5005, Australia
- ARC Centre of Excellence in Optical Microcombs for Breakthrough Science (COMBS), University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Faisal Karim
- Institute for Photonics and Advanced Sensing, School of Physical Sciences, University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - André N Luiten
- Institute for Photonics and Advanced Sensing, School of Physical Sciences, University of Adelaide, Adelaide, South Australia, 5005, Australia
- ARC Centre of Excellence in Optical Microcombs for Breakthrough Science (COMBS), University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Christopher Perrella
- Institute for Photonics and Advanced Sensing, School of Physical Sciences, University of Adelaide, Adelaide, South Australia, 5005, Australia
- ARC Centre of Excellence in Optical Microcombs for Breakthrough Science (COMBS), University of Adelaide, Adelaide, South Australia, 5005, Australia
- Centre of Light for Life and School of Biological Sciences, University of Adelaide, Adelaide, South Australia, 5005, Australia
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2
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Schmidt K, Thatcher A, Grobe A, Hicks L, Gu H, Sears DD, Ellies LG, Kalachev L, Kroll E. The Combined Treatment with Ketogenic Diet and Metformin Slows Tumor Growth in Two Mouse Models of Triple Negative Breast Cancer. RESEARCH SQUARE 2023:rs.3.rs-3664129. [PMID: 38196628 PMCID: PMC10775859 DOI: 10.21203/rs.3.rs-3664129/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
BACKGROUND Many tumors contain hypoxic microenvironments caused by inefficient tumor vascularization. Hypoxic tumors have been shown to resist conventional cancer therapies. Hypoxic cancer cells rely on glucose to meet their energetic and anabolic needs to fuel uncontrolled proliferation and metastasis. This glucose dependency is linked to a metabolic shift in response to hypoxic conditions. METHODS To leverage the glucose dependency of hypoxic tumor cells, we assessed the effects of a controlled reduction in systemic glucose by combining dietary carbohydrate restriction, using a ketogenic diet, with gluconeogenesis inhibition, using metformin, on two mouse models of triple-negative breast cancer (TNBC). RESULTS We confirmed that MET - 1 breast cancer cells require abnormally high glucose concentrations to survive in a hypoxic environment in vitro. Then, we showed that, compared to a ketogenic diet or metformin alone, animals treated with the combination regimen showed significantly lower tumor burden, higher tumor latency and slower tumor growth. As a result, lowering systemic glucose by this combined dietary and pharmacologic approach improved overall survival in our mouse model by 31 days, which is approximately equivalent to 3 human years. CONCLUSION This is the first preclinical study to demonstrate that reducing systemic glucose by combining a ketogenic diet and metformin significantly inhibits tumor proliferation and increases overall survival. Our findings suggest a possible treatment for a broad range of hypoxic and glycolytic tumor types, one that can also augment existing treatment options to improve patient outcomes.
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Affiliation(s)
- Karen Schmidt
- University of Montana Division of Biological Sciences
| | | | | | - Linda Hicks
- University of Montana Division of Biological Sciences
| | - Haiwei Gu
- Arizona State University School of Life Sciences
| | | | | | | | - Eugene Kroll
- University of Montana Missoula: University of Montana
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3
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Windholtz S, Nioi C, Coulon J, Masneuf-Pomarede I. Bioprotection by non-Saccharomyces yeasts in oenology: Evaluation of O 2 consumption and impact on acetic acid bacteria. Int J Food Microbiol 2023; 405:110338. [PMID: 37506548 DOI: 10.1016/j.ijfoodmicro.2023.110338] [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: 05/22/2023] [Revised: 07/19/2023] [Accepted: 07/20/2023] [Indexed: 07/30/2023]
Abstract
Bioprotection by yeast addition is increasingly used in oenology as an alternative to sulfur dioxide (SO2). Recent studies have also shown that it is likely to consume dissolved O2. This ability could limit O2 for other microorganisms and the early oxidation of the grape must. However, the ability of yeasts to consume O2 in a context of bioprotection was poorly studied so far considering the high genetic diversity of non-Saccharomyces. The first aim of the present study was to perform an O2 consumption rate (OCR) screening of strains from a large multi species collection found in oenology. The results demonstrate significant inter and intra species diversity with regard to O2 consumption. In the must M. pulcherrima consumes O2 faster than Saccharomyces cerevisiae and then other studied non-Saccharomyces species. The O2 consumption was also evaluate in the context of a yeast mix used as industrial bioprotection (Metschnikowia pulcherrima and Torulaspora delbrueckii) in red must. These non-Saccharomyces yeasts were then showed to limit the growth of acetic acid bacteria, with a bioprotective effect comparable to that of the addition of sulfur dioxide. Laboratory experiment confirmed the negative impact of the non-Saccharomyces yeasts on Gluconobacter oxydans that may be related to O2 consumption. This study sheds new lights on the use of bioprotection as an alternative to SO2 and suggest the possibility to use O2 consumption measurements as a new criteria for non-Saccharomyces strain selection in a context of bioprotection application for the wine industry.
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Affiliation(s)
- Sara Windholtz
- Univ. Bordeaux, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33140 Villenave d'Ornon, France; Bordeaux Sciences Agro, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33170 Gradignan, France.
| | - Claudia Nioi
- Univ. Bordeaux, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33140 Villenave d'Ornon, France; Bordeaux Sciences Agro, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33170 Gradignan, France
| | - Joana Coulon
- BioLaffort, 11 Rue Aristide Bergès, 33270 Floirac, France
| | - Isabelle Masneuf-Pomarede
- Univ. Bordeaux, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33140 Villenave d'Ornon, France; Bordeaux Sciences Agro, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33170 Gradignan, France
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4
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Langlois CR, Beier V, Karayel O, Chrustowicz J, Sherpa D, Mann M, Schulman BA. A GID E3 ligase assembly ubiquitinates an Rsp5 E3 adaptor and regulates plasma membrane transporters. EMBO Rep 2022; 23:e53835. [PMID: 35437932 PMCID: PMC9171410 DOI: 10.15252/embr.202153835] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 03/22/2022] [Accepted: 03/30/2022] [Indexed: 11/25/2022] Open
Abstract
Cells rapidly remodel their proteomes to align their cellular metabolism to environmental conditions. Ubiquitin E3 ligases enable this response, by facilitating rapid and reversible changes to protein stability, localization, or interaction partners. In Saccharomyces cerevisiae, the GID E3 ligase regulates the switch from gluconeogenic to glycolytic conditions through induction and incorporation of the substrate receptor subunit Gid4, which promotes the degradation of gluconeogenic enzymes. Here, we show an alternative substrate receptor, Gid10, which is induced in response to changes in temperature, osmolarity, and nutrient availability, regulates the ART‐Rsp5 ubiquitin ligase pathway, a component of plasma membrane quality control. Proteomic studies reveal that the levels of the adaptor protein Art2 are elevated upon GID10 deletion. A crystal structure shows the basis for Gid10‐Art2 interactions, and we demonstrate that Gid10 directs a GID E3 ligase complex to ubiquitinate Art2. Our data suggest that the GID E3 ligase affects Art2‐dependent amino acid transport. This study reveals GID as a system of E3 ligases with metabolic regulatory functions outside of glycolysis and gluconeogenesis, controlled by distinct stress‐specific substrate receptors.
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Affiliation(s)
- Christine R Langlois
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Viola Beier
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Ozge Karayel
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jakub Chrustowicz
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Dawafuti Sherpa
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Matthias Mann
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Brenda A Schulman
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, Martinsried, Germany
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5
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Ispiryan L, Borowska M, Sahin AW, Zannini E, Coffey A, Arendt EK. Lachancea fermentati FST 5.1: an alternative to baker's yeast to produce low FODMAP whole wheat bread. Food Funct 2021; 12:11262-11277. [PMID: 34710210 DOI: 10.1039/d1fo01983j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A diet low in fermentable oligo-, di-, monosaccharides and polyols (FODMAPs) is a successful therapeutic approach to alleviate symptoms of irritable bowel syndrome. However, wheat, as a fructan accumulating grain, is a major source of FODMAPs. Baker's yeast degrades fructans during fermentation, yet conventional whole wheat bread is often still high in FODMAPs. In this study, 96 yeast isolates from different environments were screened regarding their capability to metabolise FODMAPs. Two promising isolates were identified: Lachancea fermentati FST 5.1 and Cyberlindnera fabianii NTCyb, and their potential to produce low FODMAP whole wheat bread was compared to baker's yeast (Saccharomyces cerevisiae). A comprehensive characterisation of the carbohydrate metabolism by the different yeasts was achieved via HPAEC-PAD analysis of flour, doughs, and breads. L. fermentati FST 5.1 fermented fructans and excess fructose much more efficiently than baker's yeast and resulted in bread low in FODMAPs (below all cutoff levels known to induce symptoms). In contrast, C. fabianii NTCyb was unable to ferment FODMAPs in the wheat-dough-matrix. Furthermore, the yeasts' impact on the GC/MS-TOF profile of volatile aroma compounds, the sensory profile, the breads' ultrastructure, and the technological quality was examined. While C. fabianii NTCyb bread had poor technological and sensory attributes, the quality characteristics (volume, crumb structure, texture, sensory, aroma) of L. fermentati FST 5.1 bread were comparable to the baker's yeast bread. Ultimately, this study identified Lachancea fermentati FST 5.1 as an alternative to baker's yeast to produce low FODMAP whole wheat bread while maintaining optimal bread quality and consumer acceptance.
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Affiliation(s)
- Lilit Ispiryan
- University College Cork, School of Food and Nutritional Sciences, College Road, Ireland.
| | - Małgorzata Borowska
- Department of Biological Sciences, Munster Technological University, Cork, T12P928, Ireland
| | - Aylin W Sahin
- University College Cork, School of Food and Nutritional Sciences, College Road, Ireland.
| | - Emanuele Zannini
- University College Cork, School of Food and Nutritional Sciences, College Road, Ireland.
| | - Aidan Coffey
- Department of Biological Sciences, Munster Technological University, Cork, T12P928, Ireland.,APC Microbiome Ireland, Cork, Ireland
| | - Elke K Arendt
- University College Cork, School of Food and Nutritional Sciences, College Road, Ireland. .,APC Microbiome Ireland, Cork, Ireland
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6
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Gonzalez R, Morales P. Truth in wine yeast. Microb Biotechnol 2021; 15:1339-1356. [PMID: 34173338 PMCID: PMC9049622 DOI: 10.1111/1751-7915.13848] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 05/13/2021] [Accepted: 05/17/2021] [Indexed: 11/30/2022] Open
Abstract
Evolutionary history and early association with anthropogenic environments have made Saccharomyces cerevisiae the quintessential wine yeast. This species typically dominates any spontaneous wine fermentation and, until recently, virtually all commercially available wine starters belonged to this species. The Crabtree effect, and the ability to grow under fully anaerobic conditions, contribute decisively to their dominance in this environment. But not all strains of Saccharomyces cerevisiae are equally suitable as starter cultures. In this article, we review the physiological and genetic characteristics of S. cerevisiae wine strains, as well as the biotic and abiotic factors that have shaped them through evolution. Limited genetic diversity of this group of yeasts could be a constraint to solving the new challenges of oenology. However, research in this field has for many years been providing tools to increase this diversity, from genetic engineering and classical genetic tools to the inclusion of other yeast species in the catalogues of wine yeasts. On occasion, these less conventional species may contribute to the generation of interspecific hybrids with S. cerevisiae. Thus, our knowledge about wine strains of S. cerevisiae and other wine yeasts is constantly expanding. Over the last decades, wine yeast research has been a pillar for the modernisation of oenology, and we can be confident that yeast biotechnology will keep contributing to solving any challenges, such as climate change, that we may face in the future.
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Affiliation(s)
- Ramon Gonzalez
- Instituto de Ciencias de la Vid y del Vino (CSIC, Gobierno de la Rioja, Universidad de La Rioja), Finca La Grajera, Carretera de Burgos, km 6, Logroño, La Rioja, 26071, Spain
| | - Pilar Morales
- Instituto de Ciencias de la Vid y del Vino (CSIC, Gobierno de la Rioja, Universidad de La Rioja), Finca La Grajera, Carretera de Burgos, km 6, Logroño, La Rioja, 26071, Spain
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7
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Two homologs of the Cat8 transcription factor are involved in the regulation of ethanol utilization in Komagataella phaffii. Curr Genet 2021; 67:641-661. [PMID: 33725138 PMCID: PMC8254726 DOI: 10.1007/s00294-021-01165-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 02/17/2021] [Accepted: 02/18/2021] [Indexed: 11/26/2022]
Abstract
The transcription factors Cat8 and Sip4 were described in Saccharomyces cerevisiae and Kluyveromyces lactis to have very similar DNA binding domains and to be necessary for derepression of a variety of genes under non-fermentative growth conditions via binding to the carbon source responsive elements (CSREs). The methylotrophic yeast Komagataella phaffii (syn Pichia pastoris) has two transcription factors (TFs), which are putative homologs of Cat8 based on sequence similarity, termed Cat8-1 and Cat8-2. It is yet unclear in which cellular processes they are involved and if one of them is actually the homolog of Sip4. To study the roles of the Cat8 homologs in K. phaffii, overexpression or deletion strains were generated for the two TFs. The ability of these mutant strains to grow on different carbon sources was tested, and transcript levels of selected genes from the carbon metabolism were quantified. Our experiments showed that the TFs are required for the growth of K. phaffii on C2 carbon sources, but not on glucose, glycerol or methanol. K. phaffii deleted for Cat8-1 showed impaired growth on acetate, while both Cat8-1 and Cat8-2 are involved in the growth of K. phaffii on ethanol. Correspondingly, both TFs are participating in the activation of ADH2, ALD4 and ACS1, three genes encoding enzymes important for the assimilation of ethanol. Different from S. cerevisiae and K. lactis, Cat8-1 is not regulating the transcription of the putative Sip4-family member Cat8-2 in K. phaffii. Furthermore, Cat8-1 is necessary for the activation of genes from the glyoxylate cycle, whereas Cat8-2 is necessary for the activation of genes from the carnitine shuttle. Neither Cat8-1 nor Cat8-2 are required for the activation of gluconeogenesis genes. Finally, the CAT8-2 gene is repressed by the Mig1-2 transcription factor on glucose and autorepressed by the Cat8-2 protein on all tested carbon sources. Our study identified the involvement of K. phaffii Cat8-1 and Cat8-2 in C2-metabolism, and highlighted similarities and differences to their homologs in other yeast species.
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8
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Karayel O, Michaelis AC, Mann M, Schulman BA, Langlois CR. DIA-based systems biology approach unveils E3 ubiquitin ligase-dependent responses to a metabolic shift. Proc Natl Acad Sci U S A 2020; 117:32806-32815. [PMID: 33288721 PMCID: PMC7768684 DOI: 10.1073/pnas.2020197117] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The yeast Saccharomyces cerevisiae is a powerful model system for systems-wide biology screens and large-scale proteomics methods. Nearly complete proteomics coverage has been achieved owing to advances in mass spectrometry. However, it remains challenging to scale this technology for rapid and high-throughput analysis of the yeast proteome to investigate biological pathways on a global scale. Here we describe a systems biology workflow employing plate-based sample preparation and rapid, single-run, data-independent mass spectrometry analysis (DIA). Our approach is straightforward, easy to implement, and enables quantitative profiling and comparisons of hundreds of nearly complete yeast proteomes in only a few days. We evaluate its capability by characterizing changes in the yeast proteome in response to environmental perturbations, identifying distinct responses to each of them and providing a comprehensive resource of these responses. Apart from rapidly recapitulating previously observed responses, we characterized carbon source-dependent regulation of the GID E3 ligase, an important regulator of cellular metabolism during the switch between gluconeogenic and glycolytic growth conditions. This unveiled regulatory targets of the GID ligase during a metabolic switch. Our comprehensive yeast system readout pinpointed effects of a single deletion or point mutation in the GID complex on the global proteome, allowing the identification and validation of targets of the GID E3 ligase. Moreover, this approach allowed the identification of targets from multiple cellular pathways that display distinct patterns of regulation. Although developed in yeast, rapid whole-proteome-based readouts can serve as comprehensive systems-level assays in all cellular systems.
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Affiliation(s)
- Ozge Karayel
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - André C Michaelis
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Matthias Mann
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany;
| | - Brenda A Schulman
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Christine R Langlois
- Department of Molecular Machines and Signaling, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
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9
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Forkasiewicz A, Dorociak M, Stach K, Szelachowski P, Tabola R, Augoff K. The usefulness of lactate dehydrogenase measurements in current oncological practice. Cell Mol Biol Lett 2020; 25:35. [PMID: 32528540 PMCID: PMC7285607 DOI: 10.1186/s11658-020-00228-7] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 05/21/2020] [Indexed: 12/28/2022] Open
Abstract
One of the hallmarks of cancer cells is increased energy requirements associated with the higher rate of cellular proliferative activity. Metabolic changes in rapidly dividing cancer cells are closely associated with increased uptake of glucose and abnormal activity of lactate dehydrogenase (LDH), which regulates the processing of glucose to lactic acid. As serum LDH levels were found to be commonly increased in cancer patients and correlated with poor clinical outcome and resistance to therapy, the determination of LDH has become a standard supportive tool in diagnosing cancers or monitoring the effects of cancer treatment. The aim of this review is to summarize the current knowledge about methods and the practical utility for measuring both the total LDH and LDH isoenzymatic activities in the diagnosis, prognosis and prediction of cancer diseases.
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Affiliation(s)
- Agata Forkasiewicz
- Department of Surgical Education, Wroclaw Medical University, ul. Sklodowskiej-Curie 66, 50-369 Wroclaw, Poland
| | - Maja Dorociak
- Department of Surgical Education, Wroclaw Medical University, ul. Sklodowskiej-Curie 66, 50-369 Wroclaw, Poland
| | - Kamilla Stach
- Department of Biochemistry, Wroclaw Medical University, Wroclaw, Poland
| | - Piotr Szelachowski
- Department of Surgical Education, Wroclaw Medical University, ul. Sklodowskiej-Curie 66, 50-369 Wroclaw, Poland
| | - Renata Tabola
- Second Department and Clinic of General and Oncological Surgery, Wroclaw Medical University, Wroclaw, Poland
| | - Katarzyna Augoff
- Department of Surgical Education, Wroclaw Medical University, ul. Sklodowskiej-Curie 66, 50-369 Wroclaw, Poland
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10
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Zhu X, Navarro Y, Mas A, Torija MJ, Beltran G. A Rapid Method for Selecting Non- Saccharomyces Strains with a Low Ethanol Yield. Microorganisms 2020; 8:microorganisms8050658. [PMID: 32369912 PMCID: PMC7284643 DOI: 10.3390/microorganisms8050658] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/09/2020] [Accepted: 04/29/2020] [Indexed: 01/15/2023] Open
Abstract
The alcohol content in wine has increased due to external factors in recent decades. In recent reports, some non-Saccharomyces yeast species have been confirmed to reduce ethanol during the alcoholic fermentation process. Thus, an efficient screening of non-Saccharomyces yeasts with low ethanol yield is required due to the broad diversity of these yeasts. In this study, we proposed a rapid method for selecting strains with a low ethanol yield from forty-five non-Saccharomyces yeasts belonging to eighteen species. Single fermentations were carried out for this rapid selection. Then, sequential fermentations in synthetic and natural must were conducted with the selected strains to confirm their capacity to reduce ethanol compared with that of Saccharomyces cerevisiae. The results showed that ten non-Saccharomyces strains were able to reduce the ethanol content, namely, Hanseniaspora uvarum (2), Issatchenkia terricola (1), Metschnikowia pulcherrima (2), Lachancea thermotolerans (1), Saccharomycodes ludwigii (1), Torulaspora delbrueckii (2), and Zygosaccharomyces bailii (1). Compared with S. cerevisiae, the ethanol reduction of the selected strains ranged from 0.29 to 1.39% (v/v). Sequential inoculations of M. pulcherrima (Mp51 and Mp FA) and S. cerevisiae reduced the highest concentration of ethanol by 1.17 to 1.39% (v/v) in synthetic or natural must. Second, sequential fermentations with Z. bailii (Zb43) and T. delbrueckii (Td Pt) performed in natural must yielded ethanol reductions of 1.02 and 0.84% (v/v), respectively.
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11
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Kalnenieks U, Balodite E, Rutkis R. Metabolic Engineering of Bacterial Respiration: High vs. Low P/O and the Case of Zymomonas mobilis. Front Bioeng Biotechnol 2019; 7:327. [PMID: 31781557 PMCID: PMC6861446 DOI: 10.3389/fbioe.2019.00327] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 10/28/2019] [Indexed: 11/13/2022] Open
Abstract
Respiratory chain plays a pivotal role in the energy and redox balance of aerobic bacteria. By engineering respiration, it is possible to alter the efficiency of energy generation and intracellular redox state, and thus affect the key bioprocess parameters: cell yield, productivity and stress resistance. Here we summarize the current metabolic engineering and synthetic biology approaches to bacterial respiratory metabolism, with a special focus on the respiratory chain of the ethanologenic bacterium Zymomonas mobilis. Electron transport in Z. mobilis can serve as a model system of bacterial respiration with low oxidative phosphorylation efficiency. Its application for redox balancing and relevance for improvement of stress tolerance are analyzed.
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Affiliation(s)
- Uldis Kalnenieks
- Institute of Microbiology and Biotechnology, University of Latvia, Riga, Latvia
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12
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Menoncin M, Bonatto D. Molecular and biochemical aspects ofBrettanomycesin brewing. JOURNAL OF THE INSTITUTE OF BREWING 2019. [DOI: 10.1002/jib.580] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Marcelo Menoncin
- Brewing Yeast Research Group, Biotechnology Center of the Federal University of Rio Grande do Sul, Department of Molecular Biology and Biotechnology; Federal University of Rio Grande do Sul; Porto Alegre RS Brazil
| | - Diego Bonatto
- Brewing Yeast Research Group, Biotechnology Center of the Federal University of Rio Grande do Sul, Department of Molecular Biology and Biotechnology; Federal University of Rio Grande do Sul; Porto Alegre RS Brazil
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13
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Takaine M, Ueno M, Kitamura K, Imamura H, Yoshida S. Reliable imaging of ATP in living budding and fission yeast. J Cell Sci 2019; 132:jcs.230649. [PMID: 30858198 DOI: 10.1242/jcs.230649] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 03/04/2019] [Indexed: 01/12/2023] Open
Abstract
Adenosine triphosphate (ATP) is a main metabolite essential for all living organisms. However, our understanding of ATP dynamics within a single living cell is very limited. Here, we optimized the ATP-biosensor QUEEN and monitored the dynamics of ATP with good spatial and temporal resolution in living yeasts. We found stable maintenance of ATP concentration in wild-type yeasts, regardless of carbon sources or cell cycle stages, suggesting that mechanism exists to maintain ATP at a specific concentration. We further found that ATP concentration is not necessarily an indicator of metabolic activity, as there is no clear correlation between ATP level and growth rates. During fission yeast meiosis, we found a reduction in ATP levels, suggesting that ATP homeostasis is controlled by differentiation. The use of QUEEN in yeasts offers an easy and reliable assay for ATP dynamicity and will answer several unaddressed questions about cellular metabolism in eukaryotes.
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Affiliation(s)
- Masak Takaine
- Gunma University Initiative for Advanced Research (GIAR), Gunma University, Maebashi 371-8512, Japan .,Institute for Molecular and Cellular Regulation (IMCR), Gunma University, Maebashi 371-8512, Japan
| | - Masaru Ueno
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Japan.,Research Center for the Mathematics on Chromatin Live Dynamics, Hiroshima University, Japan
| | - Kenji Kitamura
- Center for Gene Science, Hiroshima University, 1-4-2 Kagamiyama, Higashi-Hiroshima 739-8527, Japan
| | - Hiromi Imamura
- Department of Functional Biology, Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
| | - Satoshi Yoshida
- Gunma University Initiative for Advanced Research (GIAR), Gunma University, Maebashi 371-8512, Japan .,Institute for Molecular and Cellular Regulation (IMCR), Gunma University, Maebashi 371-8512, Japan.,School of International Liberal Studies, Waseda University, Tokyo, 169-8050, Japan.,Japan Science and Technology Agency, PREST
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14
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De Roos J, De Vuyst L. Microbial acidification, alcoholization, and aroma production during spontaneous lambic beer production. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2019; 99:25-38. [PMID: 30246252 DOI: 10.1002/jsfa.9291] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 07/04/2018] [Accepted: 07/25/2018] [Indexed: 05/18/2023]
Abstract
Acidic beers, such as Belgian lambic beers and American and other coolship ales, are becoming increasingly popular worldwide thanks to their refreshing acidity and fruity notes. The traditional fermentation used to produce them does not apply pure yeast cultures but relies on spontaneous, environmental inoculation. The fermentation and maturation process is carried out in wooden barrels and can take up to three years. It is characterized by different microbial species belonging to the enterobacteria, acetic acid bacteria, lactic acid bacteria, and yeasts. This review provides an introduction to the technology and four fermentation strategies of beer production, followed by the microbiology of acidic beer production, focusing on the main microorganisms present during the long process used for the production of Belgian lambic beers. © 2018 Society of Chemical Industry.
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Affiliation(s)
- Jonas De Roos
- Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Luc De Vuyst
- Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
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15
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Boonekamp FJ, Dashko S, van den Broek M, Gehrmann T, Daran JM, Daran-Lapujade P. The Genetic Makeup and Expression of the Glycolytic and Fermentative Pathways Are Highly Conserved Within the Saccharomyces Genus. Front Genet 2018; 9:504. [PMID: 30505317 PMCID: PMC6250768 DOI: 10.3389/fgene.2018.00504] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 10/08/2018] [Indexed: 12/05/2022] Open
Abstract
The ability of the yeast Saccharomyces cerevisiae to convert glucose, even in the presence of oxygen, via glycolysis and the fermentative pathway to ethanol has played an important role in its domestication. Despite the extensive knowledge on these pathways in S. cerevisiae, relatively little is known about their genetic makeup in other industrially relevant Saccharomyces yeast species. In this study we explore the diversity of the glycolytic and fermentative pathways within the Saccharomyces genus using S. cerevisiae, Saccharomyces kudriavzevii, and Saccharomyces eubayanus as paradigms. Sequencing data revealed a highly conserved genetic makeup of the glycolytic and fermentative pathways in the three species in terms of number of paralogous genes. Although promoter regions were less conserved between the three species as compared to coding sequences, binding sites for Rap1, Gcr1 and Abf1, main transcriptional regulators of glycolytic and fermentative genes, were highly conserved. Transcriptome profiling of these three strains grown in aerobic batch cultivation in chemically defined medium with glucose as carbon source, revealed a remarkably similar expression of the glycolytic and fermentative genes across species, and the conserved classification of genes into major and minor paralogs. Furthermore, transplantation of the promoters of major paralogs of S. kudriavzevii and S. eubayanus into S. cerevisiae demonstrated not only the transferability of these promoters, but also the similarity of their strength and response to various environmental stimuli. The relatively low homology of S. kudriavzevii and S. eubayanus promoters to their S. cerevisiae relatives makes them very attractive alternatives for strain construction in S. cerevisiae, thereby expanding the S. cerevisiae molecular toolbox.
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Affiliation(s)
| | - Sofia Dashko
- Department of Biotechnology, Delft University of Technology, Delft, Netherlands
| | | | | | - Jean-Marc Daran
- Department of Biotechnology, Delft University of Technology, Delft, Netherlands
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16
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Vicente RL, Spina L, Gómez JPL, Dejean S, Parrou JL, François JM. Trehalose-6-phosphate promotes fermentation and glucose repression in Saccharomyces cerevisiae. MICROBIAL CELL 2018; 5:444-459. [PMID: 30386789 PMCID: PMC6206404 DOI: 10.15698/mic2018.10.651] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The yeast trehalose-6-phosphate synthase (Tps1) catalyzes the formation of trehalose-6-phosphate (T6P) in trehalose synthesis. Besides, Tps1 plays a key role in carbon and energy homeostasis in this microbial cell, as shown by the well documented loss of ATP and hyper accumulation of sugar phosphates in response to glucose addition in a mutant defective in this protein. The inability of a Saccharomyces cerevisiae tps1 mutant to cope with fermentable sugars is still a matter of debate. We reexamined this question through a quantitative analysis of the capability of TPS1 homologues from different origins to complement phenotypic defects of this mutant. Our results allowed to classify this complementation in three groups. A first group enclosed TPS1 of Klyveromyces lactis with that of S. cerevisiae as their expression in Sctps1 cells fully recovered wild type metabolic patterns and fermentation capacity in response to glucose. At the opposite was the group with TPS1 homologues from the bacteria Escherichia coli and Ralstonia solanacearum, the plant Arabidopsis thaliana and the insect Drosophila melanogaster whose metabolic profiles were comparable to those of a tps1 mutant, notably with almost no accumulation of T6P, strong impairment of ATP recovery and potent reduction of fermentation capacity, albeit these homologous genes were able to rescue growth of Sctps1 on glucose. In between was a group consisting of TPS1 homologues from other yeast species and filamentous fungi characterized by 5 to 10 times lower accumulation of T6P, a weaker recovery of ATP and a 3-times lower fermentation capacity than wild type. Finally, we found that glucose repression of gluconeogenic genes was strongly dependent on T6P. Altogether, our results suggest that the TPS protein is indispensable for growth on fermentable sugars, and points to a critical role of T6P as a sensing molecule that promotes sugar fermentation and glucose repression.
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Affiliation(s)
- Rebeca L Vicente
- LISBP; UMR INSA-CNRS 5504 & INRA 792; Toulouse, France.,Fundación Alfonso Martín Escudero; Madrid, Spain
| | - Lucie Spina
- LISBP; UMR INSA-CNRS 5504 & INRA 792; Toulouse, France
| | | | - Sebastien Dejean
- Institut de Mathématiques de Toulouse, 118 route de Narbonne, F-31062 Toulouse, France
| | | | - Jean Marie François
- LISBP; UMR INSA-CNRS 5504 & INRA 792; Toulouse, France.,Toulouse White Biotechnology Center, UMS INSA-INRA-CNRS, F-31520 Ramonville
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17
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Ferguson BS, Rogatzki MJ, Goodwin ML, Kane DA, Rightmire Z, Gladden LB. Lactate metabolism: historical context, prior misinterpretations, and current understanding. Eur J Appl Physiol 2018; 118:691-728. [PMID: 29322250 DOI: 10.1007/s00421-017-3795-6] [Citation(s) in RCA: 202] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 12/22/2017] [Indexed: 02/07/2023]
Abstract
Lactate (La-) has long been at the center of controversy in research, clinical, and athletic settings. Since its discovery in 1780, La- has often been erroneously viewed as simply a hypoxic waste product with multiple deleterious effects. Not until the 1980s, with the introduction of the cell-to-cell lactate shuttle did a paradigm shift in our understanding of the role of La- in metabolism begin. The evidence for La- as a major player in the coordination of whole-body metabolism has since grown rapidly. La- is a readily combusted fuel that is shuttled throughout the body, and it is a potent signal for angiogenesis irrespective of oxygen tension. Despite this, many fundamental discoveries about La- are still working their way into mainstream research, clinical care, and practice. The purpose of this review is to synthesize current understanding of La- metabolism via an appraisal of its robust experimental history, particularly in exercise physiology. That La- production increases during dysoxia is beyond debate, but this condition is the exception rather than the rule. Fluctuations in blood [La-] in health and disease are not typically due to low oxygen tension, a principle first demonstrated with exercise and now understood to varying degrees across disciplines. From its role in coordinating whole-body metabolism as a fuel to its role as a signaling molecule in tumors, the study of La- metabolism continues to expand and holds potential for multiple clinical applications. This review highlights La-'s central role in metabolism and amplifies our understanding of past research.
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Affiliation(s)
- Brian S Ferguson
- College of Applied Health Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Matthew J Rogatzki
- Department of Health and Exercise Science, Appalachian State University, Boone, NC, USA
| | - Matthew L Goodwin
- Department of Orthopaedics, University of Utah, Salt Lake City, UT, USA.,Huntsman Cancer Institute, Salt Lake City, UT, USA
| | - Daniel A Kane
- Department of Human Kinetics, St. Francis Xavier University, Antigonish, Canada
| | - Zachary Rightmire
- School of Kinesiology, Auburn University, 301 Wire Road, Auburn, AL, 36849, USA
| | - L Bruce Gladden
- School of Kinesiology, Auburn University, 301 Wire Road, Auburn, AL, 36849, USA.
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18
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Zhang J, Blessing D, Wu C, Liu N, Li J, Qin S, Li M. Comparative transcriptomes analysis of the wing disc between two silkworm strains with different size of wings. PLoS One 2017; 12:e0179560. [PMID: 28617839 PMCID: PMC5472328 DOI: 10.1371/journal.pone.0179560] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 05/30/2017] [Indexed: 12/19/2022] Open
Abstract
Wings of Bombyx mori (B. mori) develop from the primordium, and different B. mori strains have different wing types. In order to identify the key factors influencing B. mori wing development, we chose strains P50 and U11, which are typical for normal wing and minute wing phenotypes, respectively. We dissected the wing disc on the 1st-day of wandering stage (P50D1 and U11D1), 2nd-day of wandering stage (P50D2 and U11D2), and 3rd-day of wandering stage (P50D3 and U11D3). Subsequently, RNA-sequencing (RNA-Seq) was performed on both strains in order to construct their gene expression profiles. P50 exhibited 628 genes differentially expressed to U11, 324 up-regulated genes, and 304 down-regulated genes. Five enriched gene ontology (GO) terms were identified by GO enrichment analysis based on these differentially expressed genes (DEGs). KEGG enrichment analysis results showed that the DEGs were enriched in five pathways; of these, we identified three pathways related to the development of wings. The three pathways include amino sugar and nucleotide sugar metabolism pathway, proteasome signaling pathway, and the Hippo signaling pathway. The representative genes in the enrichment pathways were further verified by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). The RNA-Seq and qRT-PCR results were largely consistent with each other. Our results also revealed that the significantly different genes obtained in our study might be involved in the development of the size of B. mori wings. In addition, several KEGG enriched pathways might be involved in the regulation of the pathways of wing formation. These results provide a basis for further research of wing development in B. mori.
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Affiliation(s)
- Jing Zhang
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Danso Blessing
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Chenyu Wu
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Na Liu
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Juan Li
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Sheng Qin
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
- The Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang, Jiangsu, China
- * E-mail: (ML); (SQ)
| | - Muwang Li
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
- The Sericultural Research Institute, Chinese Academy of Agricultural Science, Zhenjiang, Jiangsu, China
- * E-mail: (ML); (SQ)
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19
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The Saccharomyces cerevisiae Cdk8 Mediator Represses AQY1 Transcription by Inhibiting Set1p-Dependent Histone Methylation. G3-GENES GENOMES GENETICS 2017; 7:1001-1010. [PMID: 28143948 PMCID: PMC5345701 DOI: 10.1534/g3.117.039586] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In the budding yeast Saccharomyces cerevisiae, nutrient depletion induces massive transcriptional reprogramming that relies upon communication between transcription factors, post-translational histone modifications, and the RNA polymerase II holoenzyme complex. Histone H3Lys4 methylation (H3Lys4 me), regulated by the Set1p-containing COMPASS methyltransferase complex and Jhd2p demethylase, is one of the most well-studied histone modifications. We previously demonstrated that the RNA polymerase II mediator components cyclin C-Cdk8p inhibit locus-specific H3Lys4 3me independently of Jhd2p. Here, we identify loci subject to cyclin C- and Jhd2p-dependent histone H3Lys4 3me inhibition using chromatin immunoprecipitation (ChIP)-seq. We further characterized the independent and combined roles of cyclin C and Jhd2p in controlling H3Lys4 3me and transcription in response to fermentable and nonfermentable carbon at multiple loci. These experiments suggest that H3Lys4 3me alone is insufficient to induce transcription. Interestingly, we identified an unexpected role for cyclin C-Cdk8p in repressing AQY1 transcription, an aquaporin whose expression is normally induced during nutrient deprivation. These experiments, combined with previous work in other labs, support a two-step model in which cyclin C-Cdk8p mediate AQY1 transcriptional repression by stimulating transcription factor proteolysis and preventing Set1p recruitment to the AQY1 locus.
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20
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Mookerjee SA, Gerencser AA, Nicholls DG, Brand MD. Quantifying intracellular rates of glycolytic and oxidative ATP production and consumption using extracellular flux measurements. J Biol Chem 2017; 292:7189-7207. [PMID: 28270511 DOI: 10.1074/jbc.m116.774471] [Citation(s) in RCA: 280] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 02/25/2017] [Indexed: 11/06/2022] Open
Abstract
Partitioning of ATP generation between glycolysis and oxidative phosphorylation is central to cellular bioenergetics but cumbersome to measure. We describe here how rates of ATP generation by each pathway can be calculated from simultaneous measurements of extracellular acidification and oxygen consumption. We update theoretical maximum ATP yields by mitochondria and cells catabolizing different substrates. Mitochondrial P/O ratios (mol of ATP generated per mol of [O] consumed) are 2.73 for oxidation of pyruvate plus malate and 1.64 for oxidation of succinate. Complete oxidation of glucose by cells yields up to 33.45 ATP/glucose with a maximum P/O of 2.79. We introduce novel indices to quantify bioenergetic phenotypes. The glycolytic index reports the proportion of ATP production from glycolysis and identifies cells as primarily glycolytic (glycolytic index > 50%) or primarily oxidative. The Warburg effect is a chronic increase in glycolytic index, quantified by the Warburg index. Additional indices quantify the acute flexibility of ATP supply. The Crabtree index and Pasteur index quantify the responses of oxidative and glycolytic ATP production to alterations in glycolysis and oxidative reactions, respectively; the supply flexibility index quantifies overall flexibility of ATP supply; and the bioenergetic capacity quantifies the maximum rate of total ATP production. We illustrate the determination of these indices using C2C12 myoblasts. Measurement of ATP use revealed no significant preference for glycolytic or oxidative ATP by specific ATP consumers. Overall, we demonstrate how extracellular fluxes quantitatively reflect intracellular ATP turnover and cellular bioenergetics. We provide a simple spreadsheet to calculate glycolytic and oxidative ATP production rates from raw extracellular acidification and respiration data.
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Affiliation(s)
- Shona A Mookerjee
- From Touro University California College of Pharmacy, Vallejo, California 94592 and .,the Buck Institute for Research on Aging, Novato, California 94945
| | - Akos A Gerencser
- the Buck Institute for Research on Aging, Novato, California 94945
| | - David G Nicholls
- the Buck Institute for Research on Aging, Novato, California 94945
| | - Martin D Brand
- From Touro University California College of Pharmacy, Vallejo, California 94592 and.,the Buck Institute for Research on Aging, Novato, California 94945
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21
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Microbial Ecology and Process Technology of Sourdough Fermentation. ADVANCES IN APPLIED MICROBIOLOGY 2017; 100:49-160. [PMID: 28732554 DOI: 10.1016/bs.aambs.2017.02.003] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
From a microbiological perspective, sourdough is to be considered as a specific and stressful ecosystem, harboring yeasts and lactic acid bacteria (LAB), that is used for the production of baked goods. With respect to the metabolic impact of the sourdough microbiota, acidification (LAB), flavor formation (LAB and yeasts), and leavening (yeasts and heterofermentative LAB species) are most noticeable. Three distinct types of sourdough fermentation processes can be discerned based on the inocula applied, namely backslopped ones (type 1), those initiated with starter cultures (type 2), and those initiated with a starter culture followed by backslopping (type 3). A sourdough-characteristic LAB species is Lactobacillus sanfranciscensis. A sourdough-characteristic yeast species is Candida humilis. Although it has been suggested that the microbiota of a specific sourdough may be influenced by its geographical origin, region specificity often seems to be an artefact resulting from interpretation of the research data, as those are dependent on sampling, isolation, and identification procedures. It is however clear that sourdough-adapted microorganisms are able to withstand stress conditions encountered during their growth. Based on the technological setup, type 0 (predoughs), type I (artisan bakery firm sourdoughs), type II (industrial liquid sourdoughs), and type III sourdoughs (industrial dried sourdoughs) can be distinguished. The production of all sourdoughs, independent of their classification, depends on several intrinsic and extrinsic factors. Both the flour (type, quality status, etc.) and the process parameters (fermentation temperature, pH and pH evolution, dough yield, water activity, oxygen tension, backslopping procedure and fermentation duration, etc.) determine the dynamics and outcome of (backslopped) sourdough fermentation processes.
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22
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Yeast diversity of sourdoughs and associated metabolic properties and functionalities. Int J Food Microbiol 2016; 239:26-34. [DOI: 10.1016/j.ijfoodmicro.2016.07.018] [Citation(s) in RCA: 145] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 06/09/2016] [Accepted: 07/11/2016] [Indexed: 12/30/2022]
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23
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Waifalkar P, Parit S, Chougale A, Sahoo SC, Patil P, Patil P. Immobilization of invertase on chitosan coated γ-Fe 2 O 3 magnetic nanoparticles to facilitate magnetic separation. J Colloid Interface Sci 2016; 482:159-164. [DOI: 10.1016/j.jcis.2016.07.082] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 07/29/2016] [Accepted: 07/29/2016] [Indexed: 10/21/2022]
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24
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Alonso-Moreno C, García-Yuste S. Environmental potential of the use of CO2 from alcoholic fermentation processes. The CO2-AFP strategy. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 568:319-326. [PMID: 27300565 DOI: 10.1016/j.scitotenv.2016.05.220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 05/26/2016] [Accepted: 05/31/2016] [Indexed: 06/06/2023]
Abstract
A novel Carbon Dioxide Utilization (CDU) approach from a relatively minor CO2 emission source, i.e., alcoholic fermentation processes (AFP), is presented. The CO2 produced as a by-product from the AFP is estimated by examining the EtOH consumed per year reported by the World Health Organization in 2014. It is proposed that the extremely pure CO2 from the AFP is captured in NaOH solutions to produce one of the Top 10 commodities in the chemical industry, Na2CO3, as a good example of an atomic economy process. The novel CDU strategy could yield over 30.6Mt of Na2CO3 in oversaturated aqueous solution on using ca. 12.7Mt of captured CO2 and this process would consume less energy than the synthetic methodology (Solvay ammonia soda process) and would not produce low-value by-products. The quantity of Na2CO3 obtained by this strategy could represent ca. 50% of the world Na2CO3 production in one year. In terms of the green economy, the viability of the strategy is discussed according to the recommendations of the CO2Chem network, and an estimation of the CO2negative emission achieved suggests a capture of around 280.0Mt of CO2 from now to 2020 or ca. 1.9Gt from now to 2050. Finally, the results obtained for this new CDU proposal are discussed by considering different scenarios; the CO2 production in a typical winemaking corporation, the CO2 released in the most relevant wine-producing countries, and the use of CO2 from AFP as an alternative for the top Na2CO3-producing countries.
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Affiliation(s)
- Carlos Alonso-Moreno
- Departamento de Química Inorgánica, Orgánica y Bioquímica, Facultad de Farmacia, Universidad de Castilla-La Mancha, Paseo de los Estudiantes, 02071 Albacete, Spain.
| | - Santiago García-Yuste
- Departamento de Química Inorgánica, Orgánica y Bioquímica, Facultad de Ciencias y Tecnologías Químicas, Universidad de Castilla-La Mancha, Campus Universitario, 13071 Ciudad Real, Spain.
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25
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Curiel JA, Salvadó Z, Tronchoni J, Morales P, Rodrigues AJ, Quirós M, Gonzalez R. Identification of target genes to control acetate yield during aerobic fermentation with Saccharomyces cerevisiae. Microb Cell Fact 2016; 15:156. [PMID: 27627879 PMCID: PMC5024518 DOI: 10.1186/s12934-016-0555-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 09/07/2016] [Indexed: 01/01/2023] Open
Abstract
Background Aerobic fermentation of grape must, leading to respiro-fermentative metabolism of sugars, has been proposed as way of reducing alcohol content in wines. Two factors limit the usefulness of Saccharomyces cerevisiae for this application, the Crabtree effect, and excess volatile acidity under aerobic conditions. This work aimed to explore the impact on ethanol acetate production of different S. cerevisiae strains deleted for genes previously related with the Crabtree phenotype. Results Recombinant strains were constructed on a wine industrial genetic background, FX10. All yeast strains, including FX10, showed respiro-fermentative metabolism in natural grape must under aerobic conditions, as well as a concomitant reduction in ethanol yield. This indicates that the Crabtree effect is not a major constrain for reaching relevant respiration levels in grape must. Indeed, only minor differences in ethanol yield were observed between the original and some of the recombinant strains. In contrast, some yeast strains showed a relevant reduction of acetic acid production. This was identified as a positive feature for the feasibility of alcohol level reduction by respiration. Reduced acetic acid production was confirmed by a thorough analysis of these and some additional deletion strains (involving genes HXK2, PYK1, REG1, PDE2 and PDC1). Some recombinant yeasts showed altered production of glycerol and pyruvate derived metabolites. Conclusions REG1 and PDC1 deletion strains showed a strong reduction of acetic acid yield in aerobic fermentations. Since REG1 defective strains may be obtained by non-GMO approaches, these gene modifications show good promise to help reducing ethanol content in wines. Electronic supplementary material The online version of this article (doi:10.1186/s12934-016-0555-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- José Antonio Curiel
- Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja, Departamento de Enología, Instituto de Ciencias de la Vid y del Vino, Finca La Grajera, Ctra. De Burgos Km. 6, 26007, Logroño, La Rioja, Spain
| | - Zoel Salvadó
- Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja, Departamento de Enología, Instituto de Ciencias de la Vid y del Vino, Finca La Grajera, Ctra. De Burgos Km. 6, 26007, Logroño, La Rioja, Spain
| | - Jordi Tronchoni
- Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja, Departamento de Enología, Instituto de Ciencias de la Vid y del Vino, Finca La Grajera, Ctra. De Burgos Km. 6, 26007, Logroño, La Rioja, Spain
| | - Pilar Morales
- Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja, Departamento de Enología, Instituto de Ciencias de la Vid y del Vino, Finca La Grajera, Ctra. De Burgos Km. 6, 26007, Logroño, La Rioja, Spain
| | - Alda Joao Rodrigues
- Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja, Departamento de Enología, Instituto de Ciencias de la Vid y del Vino, Finca La Grajera, Ctra. De Burgos Km. 6, 26007, Logroño, La Rioja, Spain
| | - Manuel Quirós
- Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja, Departamento de Enología, Instituto de Ciencias de la Vid y del Vino, Finca La Grajera, Ctra. De Burgos Km. 6, 26007, Logroño, La Rioja, Spain.,Evolva Biotech A/S, Copenhagen Ø, Denmark
| | - Ramón Gonzalez
- Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja, Departamento de Enología, Instituto de Ciencias de la Vid y del Vino, Finca La Grajera, Ctra. De Burgos Km. 6, 26007, Logroño, La Rioja, Spain.
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26
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Basso RF, Alcarde AR, Portugal CB. Could non-Saccharomyces yeasts contribute on innovative brewing fermentations? Food Res Int 2016. [DOI: 10.1016/j.foodres.2016.06.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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27
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Usage of different aerobic non-Saccharomyces yeasts and experimental conditions as a tool for reducing the potential ethanol content in wines. Eur Food Res Technol 2016. [DOI: 10.1007/s00217-016-2703-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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28
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Reprogramming of nonfermentative metabolism by stress-responsive transcription factors in the yeast Saccharomyces cerevisiae. Curr Genet 2016; 63:1-7. [PMID: 27180089 DOI: 10.1007/s00294-016-0609-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 05/05/2016] [Accepted: 05/07/2016] [Indexed: 12/15/2022]
Abstract
The fundamental questions of how cells control growth and respond to stresses have captivated scientists for years. Despite the complexity of these cellular processes, we could approach this puzzle by asking our favorite model yeast, Saccharomyces cerevisiae, how it makes a critical decision to either proliferate, to rest in a quiescent state or to program itself to die. This review highlights the essentiality of transcriptional factors in the reprogramming of gene expression as a prime mechanism of cellular stress responses. A whelm of evidence shows that transcriptional factors allow cells to acquire appropriate and unified responses to the transmitted signals. They function to modulate pathway-specific gene expression and organize transcriptomic responses to the altered environments. This review is aimed to summarize current knowledge on the roles of novel and well-known yeast transcription factors in the control of growth and stress responses during glucose deprivation as a prototypical case study. The scope includes stress sensing, transcription factors' identity, gene regulation and proposed crosstalks between pathways, associated with stress responses. A complex commander system of multiple stress-responsive transcription factors, observed here and elsewhere, indicates that regulation of glucose starvation/diauxic shift is a highly sophisticated and well-controlled process, involving elaborative networks of different kinase/target proteins. Using S. cerevisiae as a model, basic genetic research studies on gene identification have once again proved to be essential in the comprehension of molecular basis of cellular stress responses. Insights into this fundamental and highly conserved phenomenon will endow important prospective impacts on biotechnological applications and healthcare improvement.
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Ciani M, Morales P, Comitini F, Tronchoni J, Canonico L, Curiel JA, Oro L, Rodrigues AJ, Gonzalez R. Non-conventional Yeast Species for Lowering Ethanol Content of Wines. Front Microbiol 2016; 7:642. [PMID: 27199967 PMCID: PMC4854890 DOI: 10.3389/fmicb.2016.00642] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 04/18/2016] [Indexed: 12/20/2022] Open
Abstract
Rising sugar content in grape must, and the concomitant increase in alcohol levels in wine, are some of the main challenges affecting the winemaking industry nowadays. Among the several alternative solutions currently under study, the use of non-conventional yeasts during fermentation holds good promise for contributing to relieve this problem. Non-Saccharomyces wine yeast species comprise a high number or species, so encompassing a wider physiological diversity than Saccharomyces cerevisiae. Indeed, the current oenological interest of these microorganisms was initially triggered by their potential positive contribution to the sensorial complexity of quality wines, through the production of aroma and other sensory-active compounds. This diversity also involves ethanol yield on sugar, one of the most invariant metabolic traits of S. cerevisiae. This review gathers recent research on non-Saccharomyces yeasts, aiming to produce wines with lower alcohol content than those from pure Saccharomyces starters. Critical aspects discussed include the selection of suitable yeast strains (considering there is a noticeable intra-species diversity for ethanol yield, as shown for other fermentation traits), identification of key environmental parameters influencing ethanol yields (including the use of controlled oxygenation conditions), and managing mixed fermentations, by either the sequential or simultaneous inoculation of S. cerevisiae and non-Saccharomyces starter cultures. The feasibility, at the industrial level, of using non-Saccharomyces yeasts for reducing alcohol levels in wine will require an improved understanding of the metabolism of these alternative yeast species, as well as of the interactions between different yeast starters during the fermentation of grape must.
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Affiliation(s)
- Maurizio Ciani
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche Ancona, Italy
| | - Pilar Morales
- Instituto de Ciencias de la Vid y del Vino, Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja Logroño, Spain
| | - Francesca Comitini
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche Ancona, Italy
| | - Jordi Tronchoni
- Instituto de Ciencias de la Vid y del Vino, Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja Logroño, Spain
| | - Laura Canonico
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche Ancona, Italy
| | - José A Curiel
- Instituto de Ciencias de la Vid y del Vino, Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja Logroño, Spain
| | - Lucia Oro
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche Ancona, Italy
| | - Alda J Rodrigues
- Instituto de Ciencias de la Vid y del Vino, Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja Logroño, Spain
| | - Ramon Gonzalez
- Instituto de Ciencias de la Vid y del Vino, Consejo Superior de Investigaciones Científicas-Universidad de La Rioja-Gobierno de La Rioja Logroño, Spain
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Evolved hexose transporter enhances xylose uptake and glucose/xylose co-utilization in Saccharomyces cerevisiae. Sci Rep 2016; 6:19512. [PMID: 26781725 PMCID: PMC4726032 DOI: 10.1038/srep19512] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 12/09/2015] [Indexed: 12/24/2022] Open
Abstract
Enhancing xylose utilization has been a major focus in Saccharomyces cerevisiae strain-engineering efforts. The incentive for these studies arises from the need to use all sugars in the typical carbon mixtures that comprise standard renewable plant-biomass-based carbon sources. While major advances have been made in developing utilization pathways, the efficient import of five carbon sugars into the cell remains an important bottleneck in this endeavor. Here we use an engineered S. cerevisiae BY4742 strain, containing an established heterologous xylose utilization pathway, and imposed a laboratory evolution regime with xylose as the sole carbon source. We obtained several evolved strains with improved growth phenotypes and evaluated the best candidate using genome resequencing. We observed remarkably few single nucleotide polymorphisms in the evolved strain, among which we confirmed a single amino acid change in the hexose transporter HXT7 coding sequence to be responsible for the evolved phenotype. The mutant HXT7(F79S) shows improved xylose uptake rates (Vmax = 186.4 ± 20.1 nmol•min−1•mg−1) that allows the S. cerevisiae strain to show significant growth with xylose as the sole carbon source, as well as partial co-utilization of glucose and xylose in a mixed sugar cultivation.
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Steensels J, Daenen L, Malcorps P, Derdelinckx G, Verachtert H, Verstrepen KJ. Brettanomyces yeasts--From spoilage organisms to valuable contributors to industrial fermentations. Int J Food Microbiol 2015; 206:24-38. [PMID: 25916511 DOI: 10.1016/j.ijfoodmicro.2015.04.005] [Citation(s) in RCA: 149] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 03/23/2015] [Accepted: 04/03/2015] [Indexed: 12/13/2022]
Abstract
Ever since the introduction of controlled fermentation processes, alcoholic fermentations and Saccharomyces cerevisiae starter cultures proved to be a match made in heaven. The ability of S. cerevisiae to produce and withstand high ethanol concentrations, its pleasant flavour profile and the absence of health-threatening toxin production are only a few of the features that make it the ideal alcoholic fermentation organism. However, in certain conditions or for certain specific fermentation processes, the physiological boundaries of this species limit its applicability. Therefore, there is currently a strong interest in non-Saccharomyces (or non-conventional) yeasts with peculiar features able to replace or accompany S. cerevisiae in specific industrial fermentations. Brettanomyces (teleomorph: Dekkera), with Brettanomyces bruxellensis as the most commonly encountered representative, is such a yeast. Whilst currently mainly considered a spoilage organism responsible for off-flavour production in wine, cider or dairy products, an increasing number of authors report that in some cases, these yeasts can add beneficial (or at least interesting) aromas that increase the flavour complexity of fermented beverages, such as specialty beers. Moreover, its intriguing physiology, with its exceptional stress tolerance and peculiar carbon- and nitrogen metabolism, holds great potential for the production of bioethanol in continuous fermentors. This review summarizes the most notable metabolic features of Brettanomyces, briefly highlights recent insights in its genetic and genomic characteristics and discusses its applications in industrial fermentation processes, such as the production of beer, wine and bioethanol.
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Affiliation(s)
- Jan Steensels
- Laboratory for Genetics and Genomics, Department of Microbial and Molecular Systems (M(2)S), Centre of Microbial and Plant Genetics (CMPG), KU Leuven, Kasteelpark Arenberg 22, 3001 Leuven, Belgium; Laboratory for Systems Biology, VIB, Bio-Incubator, Gaston Geenslaan 1, 3001 Leuven, Belgium
| | - Luk Daenen
- AB-InBev SA/NV, Brouwerijplein 1, B-3000 Leuven, Belgium
| | | | - Guy Derdelinckx
- Centre for Food and Microbial Technology, Department of Microbial and Molecular Systems (M(2)S), LFoRCe, KU Leuven, Kasteelpark Arenberg 33, 3001 Leuven, Belgium
| | - Hubert Verachtert
- Centre for Food and Microbial Technology, Department of Microbial and Molecular Systems (M(2)S), LFoRCe, KU Leuven, Kasteelpark Arenberg 33, 3001 Leuven, Belgium
| | - Kevin J Verstrepen
- Laboratory for Genetics and Genomics, Department of Microbial and Molecular Systems (M(2)S), Centre of Microbial and Plant Genetics (CMPG), KU Leuven, Kasteelpark Arenberg 22, 3001 Leuven, Belgium; Laboratory for Systems Biology, VIB, Bio-Incubator, Gaston Geenslaan 1, 3001 Leuven, Belgium.
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Rogatzki MJ, Ferguson BS, Goodwin ML, Gladden LB. Lactate is always the end product of glycolysis. Front Neurosci 2015; 9:22. [PMID: 25774123 PMCID: PMC4343186 DOI: 10.3389/fnins.2015.00022] [Citation(s) in RCA: 225] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 01/13/2015] [Indexed: 12/22/2022] Open
Abstract
Through much of the history of metabolism, lactate (La−) has been considered merely a dead-end waste product during periods of dysoxia. Congruently, the end product of glycolysis has been viewed dichotomously: pyruvate in the presence of adequate oxygenation, La− in the absence of adequate oxygenation. In contrast, given the near-equilibrium nature of the lactate dehydrogenase (LDH) reaction and that LDH has a much higher activity than the putative regulatory enzymes of the glycolytic and oxidative pathways, we contend that La− is always the end product of glycolysis. Cellular La− accumulation, as opposed to flux, is dependent on (1) the rate of glycolysis, (2) oxidative enzyme activity, (3) cellular O2 level, and (4) the net rate of La− transport into (influx) or out of (efflux) the cell. For intracellular metabolism, we reintroduce the Cytosol-to-Mitochondria Lactate Shuttle. Our proposition, analogous to the phosphocreatine shuttle, purports that pyruvate, NAD+, NADH, and La− are held uniformly near equilibrium throughout the cell cytosol due to the high activity of LDH. La− is always the end product of glycolysis and represents the primary diffusing species capable of spatially linking glycolysis to oxidative phosphorylation.
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Affiliation(s)
- Matthew J Rogatzki
- Department of Health and Human Performance, University of Wisconsin-Platteville Platteville, WI, USA
| | - Brian S Ferguson
- Department of Biomedical Sciences, University of Missouri Columbia, MO, USA
| | - Matthew L Goodwin
- Department of Orthopaedics, and Huntsman Cancer Institute, University of Utah Salt Lake City, UT, USA
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Mehmood N, Husson E, Jacquard C, Wewetzer S, Büchs J, Sarazin C, Gosselin I. Impact of two ionic liquids, 1-ethyl-3-methylimidazolium acetate and 1-ethyl-3-methylimidazolium methylphosphonate, on Saccharomyces cerevisiae: metabolic, physiologic, and morphological investigations. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:17. [PMID: 25688291 PMCID: PMC4329657 DOI: 10.1186/s13068-015-0206-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 01/16/2015] [Indexed: 05/15/2023]
Abstract
BACKGROUND Ionic liquids (ILs) are considered as suitable candidates for lignocellulosic biomass pretreatment prior enzymatic saccharification and, obviously, for second-generation bioethanol production. However, several reports showed toxic or inhibitory effects of residual ILs on microorganisms, plants, and animal cells which could affect a subsequent enzymatic saccharification and fermentation process. RESULTS In this context, the impact of two hydrophilic imidazolium-based ILs already used in lignocellulosic biomass pretreatment was investigated: 1-ethyl-3-methylimidazolium acetate [Emim][OAc] and 1-ethyl-3-methylimidazolium methylphosphonate [Emim][MeO(H)PO2]. Their effects were assessed on the model yeast for ethanolic fermentation, Saccharomyces cerevisiae, grown in a culture medium containing glucose as carbon source and various IL concentrations. Classical fermentation parameters were followed: growth, glucose consumption and ethanol production, and two original factors: the respiratory status with the oxygen transfer rate (OTR) and carbon dioxide transfer rate (CTR) of yeasts which were monitored online by respiratory activity monitoring systems (RAMOS). In addition, yeast morphology was characterized by environmental scanning electron microscope (ESEM). The addition of ILs to the growth medium inhibited the OTR and switched the metabolism from respiration (conversion of glucose into biomass) to fermentation (conversion of glucose to ethanol). This behavior could be observed at low IL concentrations (≤5% IL) while above there is no significant growth or ethanol production. The presence of IL in the growth medium also induced changes of yeast morphology, which exhibited wrinkled, softened, and holed shapes. Both ILs showed the same effects, but [Emim][MeO(H)PO2] was more biocompatible than [Emim][OAc] and could be better tolerated by S. cerevisiae. CONCLUSIONS These two imidazolium-derived ILs were appropriate candidates for useful pretreatment of lignocellulosic biomass in the context of second-generation bioethanol production. This fundamental study provides additional information about the toxic effects of ILs. Indeed, the investigations highlighted the better tolerance by S. cerevisiae of [Emim][MeO(H)PO2] than [Emim][OAc].
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Affiliation(s)
- Nasir Mehmood
- />Unité Génie Enzymatique et Cellulaire, FRE-CNRS 3580, Université de Picardie Jules Verne, 33 rue Saint-Leu, 80039 Amiens Cedex, France
| | - Eric Husson
- />Unité Génie Enzymatique et Cellulaire, FRE-CNRS 3580, Université de Picardie Jules Verne, 33 rue Saint-Leu, 80039 Amiens Cedex, France
| | - Cédric Jacquard
- />Unité de Recherche Vignes et Vins de Champagne—UPRES-EA 4707, Université de Reims Champagne-Ardenne, BP1039, 51687 Reims Cedex 2, France
| | - Sandra Wewetzer
- />AVT—Biochemical Engineering, RWTH Aachen University, Aachen, Germany
| | - Jochen Büchs
- />AVT—Biochemical Engineering, RWTH Aachen University, Aachen, Germany
| | - Catherine Sarazin
- />Unité Génie Enzymatique et Cellulaire, FRE-CNRS 3580, Université de Picardie Jules Verne, 33 rue Saint-Leu, 80039 Amiens Cedex, France
| | - Isabelle Gosselin
- />Unité Génie Enzymatique et Cellulaire, FRE-CNRS 3580, Université de Picardie Jules Verne, 33 rue Saint-Leu, 80039 Amiens Cedex, France
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Gélinas P. Fermentation Control in Baker's Yeast Production: Mapping Patents. Compr Rev Food Sci Food Saf 2014. [DOI: 10.1111/1541-4337.12107] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Pierre Gélinas
- the Food Research and Development Centre; Agriculture and Agri-Food Canada; Saint-Hyacinthe Quebec Canada J2 8E3
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Thepnok P, Ratanakhanokchai K, Soontorngun N. The novel zinc cluster regulator Tog1 plays important roles in oleate utilization and oxidative stress response in Saccharomyces cerevisiae. Biochem Biophys Res Commun 2014; 450:1276-82. [PMID: 24998441 DOI: 10.1016/j.bbrc.2014.06.128] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 06/25/2014] [Indexed: 11/29/2022]
Abstract
Many zinc cluster proteins have been shown to play a role in the transcriptional regulation of glucose-repressible genes during glucose exhaustion and diauxic shift. Here, we studied an additional member of this family called Yer184c (herein called Tog1) for transcriptional regulator of oleate. Our results showed that a Δtog1 strain displays impaired growth with several non-fermentable carbons. Tog1 is also implicated in oxidative stress tolerance. Importantly, during the glucose-oleate shift, combined results from quantitative real time-PCR and chromatin immunoprecipitation (ChIP) experiments showed that Tog1 acts as a direct activator of oleate utilizing genes, encoded key enzymes in β-Oxidation and NADPH regeneration (POX1, FOX2, POT1 and IDP2), the glyoxylate shunt (MLS1 and ICL1), and gluconeogenesis (PCK1 and FBP1). A transmission electron microscopy (TEM) analysis of the Δtog1 strain assayed with oleate also revealed a substantial decrease in peroxisome abundance that is vital for fatty acid oxidation. Overall, our results clearly demonstrated that Tog1 is a newly characterized zinc cluster regulator that functions in the complex network of non-fermentable carbon metabolism in Saccharomyces cerevisiae.
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Affiliation(s)
- Piyasuda Thepnok
- Division of Biochemical Technology, School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, 49 Tianthalay Road, Tha Kham, Bangkhuntian, Bangkok 10150, Thailand
| | - Khanok Ratanakhanokchai
- Division of Biochemical Technology, School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, 49 Tianthalay Road, Tha Kham, Bangkhuntian, Bangkok 10150, Thailand
| | - Nitnipa Soontorngun
- Division of Biochemical Technology, School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, 49 Tianthalay Road, Tha Kham, Bangkhuntian, Bangkok 10150, Thailand.
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Mates N, Kettner K, Heidenreich F, Pursche T, Migotti R, Kahlert G, Kuhlisch E, Breunig KD, Schellenberger W, Dittmar G, Hoflack B, Kriegel TM. Proteomic and functional consequences of hexokinase deficiency in glucose-repressible Kluyveromyces lactis. Mol Cell Proteomics 2014; 13:860-75. [PMID: 24434903 DOI: 10.1074/mcp.m113.032714] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The analysis of glucose signaling in the Crabtree-positive eukaryotic model organism Saccharomyces cerevisiae has disclosed a dual role of its hexokinase ScHxk2, which acts as a glycolytic enzyme and key signal transducer adapting central metabolism to glucose availability. In order to identify evolutionarily conserved characteristics of hexokinase structure and function, the cellular response of the Crabtree-negative yeast Kluyveromyces lactis to rag5 null mutation and concomitant deficiency of its unique hexokinase KlHxk1 was analyzed by means of difference gel electrophoresis. In total, 2,851 fluorescent spots containing different protein species were detected in the master gel representing all of the K. lactis proteins that were solubilized from glucose-grown KlHxk1 wild-type and mutant cells. Mass spectrometric peptide analysis identified 45 individual hexokinase-dependent proteins related to carbohydrate, short-chain fatty acid and tricarboxylic acid metabolism as well as to amino acid and protein turnover, but also to general stress response and chromatin remodeling, which occurred as a consequence of KlHxk1 deficiency at a minimum 3-fold enhanced or reduced level in the mutant proteome. In addition, three proteins exhibiting homology to 2-methylcitrate cycle enzymes of S. cerevisiae were detected at increased concentrations, suggesting a stimulation of pyruvate formation from amino acids and/or fatty acids. Experimental validation of the difference gel electrophoresis approach by post-lysis dimethyl labeling largely confirmed the abundance changes detected in the mutant proteome via the former method. Taking into consideration the high proportion of identified hexokinase-dependent proteins exhibiting increased proteomic levels, KlHxk1 is likely to have a repressive function in a multitude of metabolic pathways. The proteomic alterations detected in the mutant classify KlHxk1 as a multifunctional enzyme and support the view of evolutionary conservation of dual-role hexokinases even in organisms that are less specialized than S. cerevisiae in terms of glucose utilization.
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Affiliation(s)
- Nadia Mates
- Technische Universität Dresden, Medizinische Fakultät Carl Gustav Carus, Institute of Physiological Chemistry, D-01307 Dresden, Germany
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Clanton TL, Hogan MC, Gladden LB. Regulation of cellular gas exchange, oxygen sensing, and metabolic control. Compr Physiol 2013; 3:1135-90. [PMID: 23897683 DOI: 10.1002/cphy.c120030] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cells must continuously monitor and couple their metabolic requirements for ATP utilization with their ability to take up O2 for mitochondrial respiration. When O2 uptake and delivery move out of homeostasis, cells have elaborate and diverse sensing and response systems to compensate. In this review, we explore the biophysics of O2 and gas diffusion in the cell, how intracellular O2 is regulated, how intracellular O2 levels are sensed and how sensing systems impact mitochondrial respiration and shifts in metabolic pathways. Particular attention is paid to how O2 affects the redox state of the cell, as well as the NO, H2S, and CO concentrations. We also explore how these agents can affect various aspects of gas exchange and activate acute signaling pathways that promote survival. Two kinds of challenges to gas exchange are also discussed in detail: when insufficient O2 is available for respiration (hypoxia) and when metabolic requirements test the limits of gas exchange (exercising skeletal muscle). This review also focuses on responses to acute hypoxia in the context of the original "unifying theory of hypoxia tolerance" as expressed by Hochachka and colleagues. It includes discourse on the regulation of mitochondrial electron transport, metabolic suppression, shifts in metabolic pathways, and recruitment of cell survival pathways preventing collapse of membrane potential and nuclear apoptosis. Regarding exercise, the issues discussed relate to the O2 sensitivity of metabolic rate, O2 kinetics in exercise, and influences of available O2 on glycolysis and lactate production.
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Affiliation(s)
- T L Clanton
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA.
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Lavrentovich MO, Koschwanez JH, Nelson DR. Nutrient shielding in clusters of cells. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 87:062703. [PMID: 23848711 PMCID: PMC4122756 DOI: 10.1103/physreve.87.062703] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Indexed: 06/02/2023]
Abstract
Cellular nutrient consumption is influenced by both the nutrient uptake kinetics of an individual cell and the cells' spatial arrangement. Large cell clusters or colonies have inhibited growth at the cluster's center due to the shielding of nutrients by the cells closer to the surface. We develop an effective medium theory that predicts a thickness ℓ of the outer shell of cells in the cluster that receives enough nutrient to grow. The cells are treated as partially absorbing identical spherical nutrient sinks, and we identify a dimensionless parameter ν that characterizes the absorption strength of each cell. The parameter ν can vary over many orders of magnitude among different cell types, ranging from bacteria and yeast to human tissue. The thickness ℓ decreases with increasing ν, increasing cell volume fraction φ, and decreasing ambient nutrient concentration ψ(∞). The theoretical results are compared with numerical simulations and experiments. In the latter studies, colonies of budding yeast, Saccharomyces cerevisiae, are grown on glucose media and imaged under a confocal microscope. We measure the growth inside the colonies via a fluorescent protein reporter and compare the experimental and theoretical results for the thickness ℓ.
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Rodicio R, Heinisch JJ. Yeast on the milky way: genetics, physiology and biotechnology of Kluyveromyces lactis. Yeast 2013; 30:165-77. [PMID: 23576126 DOI: 10.1002/yea.2954] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Revised: 03/08/2013] [Accepted: 03/12/2013] [Indexed: 11/08/2022] Open
Abstract
The milk yeast Kluyveromyces lactis has a life cycle similar to that of Saccharomyces cerevisiae and can be employed as a model eukaryote using classical genetics, such as the combination of desired traits, by crossing and tetrad analysis. Likewise, a growing set of vectors, marker cassettes and tags for fluorescence microscopy are available for manipulation by genetic engineering and investigating its basic cell biology. We here summarize these applications, as well as the current knowledge regarding its central metabolism, glucose and extracellular stress signalling pathways. A short overview on the biotechnological potential of K. lactis concludes this review.
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Affiliation(s)
- Rosaura Rodicio
- Departamento de Bioquímica y Biología Molecular and Instituto Universitario de Biotecnología de Asturias, Universidad de Oviedo, Spain
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40
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Yeast respiration of sugars by non-Saccharomyces yeast species: A promising and barely explored approach to lowering alcohol content of wines. Trends Food Sci Technol 2013. [DOI: 10.1016/j.tifs.2012.06.015] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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41
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Suppi S, Michelson T, Viigand K, Alamäe T. Repression vs. activation of MOX, FMD, MPP1 and MAL1 promoters by sugars in Hansenula polymorpha: the outcome depends on cell's ability to phosphorylate sugar. FEMS Yeast Res 2012; 13:219-32. [PMID: 23164245 DOI: 10.1111/1567-1364.12023] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 11/08/2012] [Indexed: 12/01/2022] Open
Abstract
A high-throughput approach was used to assess the effect of mono- and disaccharides on MOX, FMD, MPP1 and MAL1 promoters in Hansenula polymorpha. Site-specifically designed strains deficient for (1) hexokinase, (2) hexokinase and glucokinase, (3) maltose permease or (4) maltase were used as hosts for reporter plasmids in which β-glucuronidase (Gus) expression was controlled by these promoters. The reporter strains were grown on agar plates containing varied carbon sources and Gus activity was measured in permeabilized cells on microtitre plates. We report that monosaccharides (glucose, fructose) repress studied promoters only if phosphorylated in the cell. Glucose-6-phosphate was proposed as a sugar repression signalling metabolite for H. polymorpha. Intriguingly, glucose and fructose strongly activated expression from these promoters in strains lacking both hexokinase and glucokinase, indicating that unphosphorylated monosaccharides have promoter-derepressing effect. We also show that maltose and sucrose must be internalized and split into monosaccharides to exert repression on MOX promoter. We demonstrate that at yeast growth on glucose-containing agar medium, glucose-limitation is rapidly created that promotes derepression of methanol-specific promoters and that derepression is specifically enhanced in hexokinase-negative strain. We recommend double kinase-negative and hexokinase-negative mutants as hosts for heterologous protein production from MOX and FMD promoters.
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Affiliation(s)
- Sandra Suppi
- Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
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Ring J, Sommer C, Carmona-Gutierrez D, Ruckenstuhl C, Eisenberg T, Madeo F. The metabolism beyond programmed cell death in yeast. Exp Cell Res 2012; 318:1193-200. [PMID: 22480867 PMCID: PMC3396845 DOI: 10.1016/j.yexcr.2012.03.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 03/19/2012] [Accepted: 03/21/2012] [Indexed: 12/15/2022]
Abstract
A cell's reaction to any change in the endogenous or exogenous conditions often involves a complex response that eventually either leads to cell adaptation and survival or to the initiation and execution of (programmed) cell death. The molecular decision whether to live or die, while depending on a cell's genome, is fundamentally influenced by its actual metabolic status. Thus, the collection of all metabolites present in a biological system at a certain time point (the so-called metabolome) defines its physiological, developmental and pathological state and determines its fate during changing and stressful conditions. The budding yeast Saccharomyces cerevisiae is a unicellular organism that allows to easily modify and monitor conditions affecting the cell's metabolome, for instance through a simple change of the nutrition source. Such changes can be used to mimic and study (patho)physiological scenarios, including caloric restriction and longevity, the Warburg effect in cancer cells or changes in mitochondrial mass affecting cell death. In addition, disruption of single genes or generation of respiratory deficiency (via abrogation of mitochondrial DNA) assists in revealing connections between metabolism and apoptosis. In this minireview, we discuss recent studies using the potential of the yeast model to provide new insights into the processes of stress defense, cell death and longevity.
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Affiliation(s)
- Julia Ring
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Cornelia Sommer
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | | | - Christoph Ruckenstuhl
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
- Institute of Pathology, Medical University of Graz, Austria
| | - Tobias Eisenberg
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Frank Madeo
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
- Corresponding author.
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Soontorngun N, Baramee S, Tangsombatvichit C, Thepnok P, Cheevadhanarak S, Robert F, Turcotte B. Genome-wide location analysis reveals an important overlap between the targets of the yeast transcriptional regulators Rds2 and Adr1. Biochem Biophys Res Commun 2012; 423:632-7. [PMID: 22687600 DOI: 10.1016/j.bbrc.2012.05.151] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 05/26/2012] [Indexed: 10/28/2022]
Abstract
Upon glucose depletion, a massive reprogramming of gene expression occurs in the yeast Saccharomyces cerevisiae for the use of alternate carbon sources such as the nonfermentable compounds ethanol and glycerol. This process is mediated by the master kinase Snf1 that controls the activity of various targets including the transcriptional regulators Cat8, Sip4 and Adr1. We have recently identified Rds2 as an additional player in this pathway. Here, we have performed genome-wide location analysis of Rds2 in cells grown in the presence of glycerol. We show that Rds2 binds to promoters of genes involved in gluconeogenesis, the glyoxylate shunt, and the TCA cycle as well as some genes encoding mitochondrial components or some involved in the stress response. Interestingly, we also detected Rds2 at the promoters of SIP4, ADR1 and HAP4 which encodes the limiting subunit of the Hap2/3/4/5 complex, a regulator of respiration. Strikingly, we observed an important overlap between the targets of Rds2 and Adr1. Finally, we provide a model to account for the complex interplay among these transcriptional regulators.
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Affiliation(s)
- Nitnipa Soontorngun
- Division of Biochemical Technology, School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, 49 Tianthalay Road, Tha Kham, Bang Khuntian, Bangkok 10150, Thailand.
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Kettner K, Krause U, Mosler S, Bodenstein C, Kriegel TM, Rödel G. Saccharomyces cerevisiae gene YMR291W/TDA1 mediates the in vivo phosphorylation of hexokinase isoenzyme 2 at serine-15. FEBS Lett 2012; 586:455-8. [PMID: 22289182 DOI: 10.1016/j.febslet.2012.01.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 01/11/2012] [Accepted: 01/16/2012] [Indexed: 11/16/2022]
Abstract
Hxk2 is the predominant hexokinase of Saccharomyces cerevisiae during growth on glucose. In addition to its role in glycolysis, the enzyme is involved in glucose sensing and regulation of gene expression. Glucose limitation causes the phosphorylation of Hxk2 at serine-15 which affects the nucleo-cytoplasmic distribution and dimer stability of the enzyme. In order to identify the responsible kinase, we screened selected protein kinase single-gene deletion mutants by high resolution clear native PAGE. Deletion of YMR291W/TDA1 resulted in the absence of the Hxk2 phosphomonomer, indicating an indispensable role of the corresponding protein in Hxk2 phosphorylation.
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Affiliation(s)
- Karina Kettner
- Institut für Physiologische Chemie, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
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Physiological and metabolic diversity in the yeast Kluyveromyces marxianus. Antonie van Leeuwenhoek 2011; 100:507-19. [DOI: 10.1007/s10482-011-9606-x] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Accepted: 06/03/2011] [Indexed: 10/18/2022]
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46
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Jeon Y, Shin HS, Rogers P. Xylitol production from a mutant strain of Candida tropicalis. Lett Appl Microbiol 2011; 53:106-13. [DOI: 10.1111/j.1472-765x.2011.03078.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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de Barros Pita W, Leite FCB, de Souza Liberal AT, Simões DA, de Morais MA. The ability to use nitrate confers advantage to Dekkera bruxellensis over S. cerevisiae and can explain its adaptation to industrial fermentation processes. Antonie van Leeuwenhoek 2011; 100:99-107. [PMID: 21350883 DOI: 10.1007/s10482-011-9568-z] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 02/18/2011] [Indexed: 10/18/2022]
Abstract
The yeast Dekkera bruxellensis has been regarded as a contamination problem in industrial ethanol production because it can replace the originally inoculated Saccharomyces cerevisiae strains. The present study deals with the influence of nitrate on the relative competitiveness of D. bruxellensis and S. cerevisiae in sugar cane ethanol fermentations. The industrial strain D. bruxellensis GDB 248 showed higher growth rates than S. cerevisiae JP1 strain in mixed ammonia/nitrate media, and nitrate assimilation genes were only slightly repressed by ammonia. These characteristics rendered D. bruxellensis cells with an ability to overcome S. cerevisiae populations in both synthetic medium and in sugar cane juice. The results were corroborated by data from industrial fermentations that showed a correlation between high nitrate concentrations and high D. bruxellensis cell counts. Moreover, the presence of nitrate increased fermentation efficiency of D. bruxellensis cells in anaerobic conditions, which may explain the maintenance of ethanol production in the presence of D. bruxellensis in industrial processes. The presence of high levels of nitrate in sugar cane juice may be due to its inefficient conversion by plant metabolism in certain soil types and could explain the periodical episodes of D. bruxellensis colonization of Brazilian ethanol plants.
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Affiliation(s)
- Will de Barros Pita
- Interdepartmental Research Group on Metabolic Engineering, Federal University of Pernambuco, Recife, PE, Brazil
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Barnett JA. A history of research on yeasts 14: medical yeasts part 2, Cryptococcus neoformans. Yeast 2011; 27:875-904. [PMID: 20641025 DOI: 10.1002/yea.1786] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Affiliation(s)
- James A Barnett
- School of Biological Sciences, University of East Anglia, Norwich, UK.
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Stadler AM, Harrowfield J. Places and chemistry: Strasbourg—a chemical crucible seen through historical personalities. Chem Soc Rev 2011; 40:2061-108. [DOI: 10.1039/c0cs00197j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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50
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Phosphoglycerate mutase knock-out mutant Saccharomyces cerevisiae: Physiological investigation and transcriptome analysis. Biotechnol J 2010; 5:1016-27. [DOI: 10.1002/biot.201000199] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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