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Daute M, Jack F, Walker G. The potential for Scotch Malt Whisky flavour diversification by yeast. FEMS Yeast Res 2024; 24:foae017. [PMID: 38684485 PMCID: PMC11095643 DOI: 10.1093/femsyr/foae017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 04/13/2024] [Accepted: 04/28/2024] [Indexed: 05/02/2024] Open
Abstract
Scotch Whisky, a product of high importance to Scotland, has gained global approval for its distinctive qualities derived from the traditional production process, which is defined in law. However, ongoing research continuously enhances Scotch Whisky production and is fostering a diversification of flavour profiles. To be classified as Scotch Whisky, the final spirit needs to retain the aroma and taste of 'Scotch'. While each production step contributes significantly to whisky flavour-from malt preparation and mashing to fermentation, distillation, and maturation-the impact of yeast during fermentation is crucially important. Not only does the yeast convert the sugar to alcohol, it also produces important volatile compounds, e.g. esters and higher alcohols, that contribute to the final flavour profile of whisky. The yeast chosen for whisky fermentations can significantly influence whisky flavour, so the yeast strain employed is of high importance. This review explores the role of yeast in Scotch Whisky production and its influence on flavour diversification. Furthermore, an extensive examination of nonconventional yeasts employed in brewing and winemaking is undertaken to assess their potential suitability for adoption as Scotch Whisky yeast strains, followed by a review of methods for evaluating new yeast strains.
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Affiliation(s)
- Martina Daute
- Division of Engineering and Food Sciences, School of Applied Sciences, Abertay University, Bell St, DD1 1HG, Dundee, Scotland
- The Scotch Whisky Research Institute, Research Ave N, EH14 4AP, Edinburgh, Scotland
| | - Frances Jack
- The Scotch Whisky Research Institute, Research Ave N, EH14 4AP, Edinburgh, Scotland
| | - Graeme Walker
- Division of Engineering and Food Sciences, School of Applied Sciences, Abertay University, Bell St, DD1 1HG, Dundee, Scotland
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Cui Y, Guo P, Ning M, Yue Y, Yuan Y, Yue T. Kluyveromyces marxianus supplementation ameliorates alcohol-induced liver injury associated with the modulation of gut microbiota in mice. Food Funct 2023; 14:9920-9935. [PMID: 37853829 DOI: 10.1039/d3fo01796f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2023]
Abstract
The aim of this study was to evaluate the intervention effect of the potential probiotic Kluyveromyces marxianus YG-4 isolated from Tibetan kefir grains on alcoholic liver disease (ALD). Eight-week-old male C57BL/6J mice were fed with a Lieber-DeCarli (LDC) diet containing ethanol with a progressively increasing concentration from 1% to 4% (vol/vol) to establish an ALD mouse model. Our results suggested that K. marxianus treatment improved ALD, as demonstrated by the reduction of serum ALT and AST levels and the suppression of TLR4/NF-κB-mediated inflammatory response in the liver. K. marxianus administration significantly elevated antioxidant activities of SOD, CAT and GSH-Px, and reduced the MDA level in mice. K. marxianus supplementation repaired the gut barrier by increasing tight junction proteins and the number of goblet cells in the colon of ALD mice. In addition, treatment with K. marxianus restored alcohol-induced gut dysbiosis. Specifically, K. marxianus administration depleted the abundance of Lactobacillus, Coriobacteriaceae_UCG-002 and Candida, while increased that of Allobaculum, Dubosiella and Epicoccum in mice. Our findings open new possibilities for K. marxianus application in ALD treatment.
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Affiliation(s)
- Yuanyuan Cui
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China.
- Laboratory of Quality & Safety Risk Assessment for Agro-products (Yangling), Ministry of Agriculture, Yangling, 712100, China.
| | - Peng Guo
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China.
- Laboratory of Quality & Safety Risk Assessment for Agro-products (Yangling), Ministry of Agriculture, Yangling, 712100, China.
| | - Mengge Ning
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China.
- Laboratory of Quality & Safety Risk Assessment for Agro-products (Yangling), Ministry of Agriculture, Yangling, 712100, China.
| | - Yuan Yue
- Xi'an Gaoxin No. 1 High School, Xi'an, 710119, China
| | - Yahong Yuan
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China.
- Laboratory of Quality & Safety Risk Assessment for Agro-products (Yangling), Ministry of Agriculture, Yangling, 712100, China.
- College of Food Science and Technology, Northwest University, Xi'an, 710069, China
| | - Tianli Yue
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, China.
- Laboratory of Quality & Safety Risk Assessment for Agro-products (Yangling), Ministry of Agriculture, Yangling, 712100, China.
- College of Food Science and Technology, Northwest University, Xi'an, 710069, China
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Fonseca GG. Metabolic engineering of Kluyveromyces marxianus for biomass-based applications. 3 Biotech 2022; 12:259. [PMID: 36068842 PMCID: PMC9440961 DOI: 10.1007/s13205-022-03324-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 08/22/2022] [Indexed: 11/01/2022] Open
Abstract
Kluyveromyces marxianus ATCC 26,548 was cultivated in aerobic chemostats with [1-13C] and [U-13C] glucose as carbon source under three different growth conditions (0.10, 0.25, and 0.5 h-1) to evaluate metabolic fluxes. Carbon balances closed always within 97-102%. Growth was carbon limited, and the cell yield on glucose was the same. The extracellular side-product formation was very low, totaling 0.0008 C-mol C-mol-1 substrate at 0.5 h-1. The intracellular flux ratios did not show significant variation for metabolic flux analysis from labelling and biomass composition and metabolic flux ratio analysis from labelling. The observed strictly oxidative metabolism and the stability of the metabolism in terms of fluxes even at high growth rates, without triggering out the synthesis of by-products, is an extremely desired condition that underlines the potential of K. marxianus for biotechnological biomass-related applications and the comprehension of the metabolic pools and pathways is an important step to engineering this organism. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-022-03324-x.
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Affiliation(s)
- Gustavo Graciano Fonseca
- Faculty of Natural Resource Sciences, School of Business and Science, University of Akureyri, Borgir v. Nordurslod, 600 Akureyri, Iceland
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Ojeda-Linares CI, Solís-García IA, Casas A. Constructing Micro-Landscapes: Management and Selection Practices on Microbial Communities in a Traditional Fermented Beverage. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.821268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Colonche is a traditional beverage produced in Mexico by the fermentation of fruits of several cacti species. In the Meridional Central Plateau region of Mexico, where this study was conducted, it is mainly produced with fruits of Opuntia streptacantha; there, the producers perform spontaneous fermentation and/or fermentations through inoculums. Several factors can change the microbial community structure and dynamics through the fermentation process, but little attention has been directed to evaluate what type and extent of change the human practices have over the microbial communities. This study aims to assess the microbiota under spontaneous and inoculated fermentation techniques, the microorganisms present in the inoculums and containers, and the changes of microbiota during the process of producing colonche with different techniques. We used next-generation sequencing of the V3-V4 regions of the 16S rRNA gene and the ITS2, to characterize bacterial and fungal diversity associated with the different fermentation techniques. We identified 701 bacterial and 203 fungal amplicon sequence variants (ASVs) belonging to 173 bacterial and 187 fungal genera. The alpha and beta diversity analysis confirmed that both types of fermentation practices displayed differences in richness, diversity, and community structure. Richness of bacteria in spontaneous fermentation (0D = 136 ± 0.433) was higher than in the inoculated samples (0D = 128 ± 0.929), while fungal richness in the inoculated samples (0D = 32 ± 0.539) was higher than in spontaneous samples (0D = 19 ± 0.917). We identified bacterial groups like Lactobacillus, Leuconostoc, Pediococcus and the Saccharomyces yeast shared in ferments managed with different practices; these organisms are commonly related to the quality of the fermentation process. We identified that clay pots, where spontaneous fermentation is carried out, have an outstanding diversity of fungal and bacterial richness involved in fermentation, being valuable reservoirs of microorganisms for future fermentations. The inoculums displayed the lowest richness and diversity of bacterial and fungal communities suggesting unconscious selection on specific microbial consortia. The beta diversity analysis identified an overlap in microbial communities for both types of fermentation practices, which might reflect a shared composition of microorganisms occurring in the Opuntia streptacantha substrate. The variation in the spontaneous bacterial community is consistent with alpha diversity data, while fungal communities showed less differences among treatments, probably due to the high abundance and dominance of Saccharomyces. This information illustrates how traditional management guides selection and may drive changes in the microbial consortia to produce unique fermented beverages through specific fermentation practices. Although further studies are needed to analyze more specifically the advantages of each fermentation type over the quality of the product, our current analysis supports the role of traditional knowledge driving it and the relevance of plans for its conservation.
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Optimization of 2-Phenylethanol Production from Sweet Whey Fermentation Using Kluyveromyces marxianus. FERMENTATION-BASEL 2022. [DOI: 10.3390/fermentation8020039] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The growing demand for natural products benefits the development of bioprocesses to obtain value-added compounds using residues such as sweet whey, which is rich in lactose. The yeast Kluyveromyces marxianus can ferment sweet whey to obtain 2-phenylethanol (2-PhEtOH), which is a superior alcohol with a rose aroma. Such fermentation only requires the addition of L-phenylalanine (precursor) and (NH4)2SO4 (salt). Therefore, it was sought to improve the fermentation conditions to produce 2-PhEtOH, which, in turn, would achieve the maximum decrease in the Chemical Oxygen Demand (COD) of the fermentation medium. With the use of the Response Surface Methodology and the application of a Central Composite Design for optimization, two parameters were evaluated as a function of time: salt concentration and precursor. The experimental data were adjusted to a second order polynomial, identifying that the precursor concentration presents a statistically significant effect. The best conditions were: 4.50 g/L of precursor and 0.76 g/L of salt, with a maximum production of 1.2 g/L (2-PhEtOH) at 48 h and achieving a maximum percentage of COD removal of 76% at 96 h. Finally, the optimal conditions were experimentally validated, recommending the use of the model.
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6
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Metabolic heat responses of Kluyveromyces marxianus and Saccharomyces cerevisiae during Carboxypeptidase Y Enzyme production. Process Biochem 2022. [DOI: 10.1016/j.procbio.2021.11.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Leonel LV, Arruda PV, Chandel AK, Felipe MGA, Sene L. Kluyveromyces marxianus: a potential biocatalyst of renewable chemicals and lignocellulosic ethanol production. Crit Rev Biotechnol 2021; 41:1131-1152. [PMID: 33938342 DOI: 10.1080/07388551.2021.1917505] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Kluyveromyces marxianus is an ascomycetous yeast which has shown promising results in cellulosic ethanol and renewable chemicals production. It can survive on a variety of carbon sources under industrially favorable conditions due to its fast growth rate, thermotolerance, and acid tolerance. K. marxianus, is generally regarded as a safe (GRAS) microorganism, is widely recognized as a powerhouse for the production of heterologous proteins and is accepted by the US Food and Drug Administration (USFDA) for its pharmaceutical and food applications. Since lignocellulosic hydrolysates are comprised of diverse monomeric sugars, oligosaccharides and potential metabolism inhibiting compounds, this microorganism can play a pivotal role as it can grow on lignocellulosic hydrolysates coping with vegetal cell wall derived inhibitors. Furthermore, advancements in synthetic biology, for example CRISPR-Cas9 (clustered regularly interspaced short palindromic repeats with Cas9)-mediated genome editing, will enable development of an engineered yeast for the production of biochemicals and biopharmaceuticals having a myriad of industrial applications. Genetic engineering companies such as Cargill, Ginkgo Bioworks, DuPont, Global Yeast, Genomatica, and several others are actively working to develop designer yeasts. Given the important traits and properties of K. marxianus, these companies may find it to be a suitable biocatalyst for renewable chemicals and fuel production on the large scale. This paper reviews the recent progress made with K. marxianus biotechnology for sustainable production of ethanol, and other products utilizing lignocellulosic sugars.
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Affiliation(s)
- L V Leonel
- Center of Exact and Technological Sciences - CCET, State University of West Paraná, Cascavel, Brazil
| | - P V Arruda
- Department of Bioprocess Engineering and Biotechnology - COEBB/TD, Federal University of Technology - Paraná (UTFPR), Toledo, Brazil
| | - A K Chandel
- Department of Biotechnology, School of Engineering of Lorena - EEL, University of São Paulo, Lorena, Brazil
| | - M G A Felipe
- Department of Biotechnology, School of Engineering of Lorena - EEL, University of São Paulo, Lorena, Brazil
| | - L Sene
- Center of Exact and Technological Sciences - CCET, State University of West Paraná, Cascavel, Brazil
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8
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Löser C, Kupsch C, Walther T, Hoffmann A. A new approach for balancing the microbial synthesis of ethyl acetate and other volatile metabolites during aerobic bioreactor cultivations. Eng Life Sci 2021; 21:137-153. [PMID: 33716613 PMCID: PMC7923609 DOI: 10.1002/elsc.202000047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 10/23/2020] [Indexed: 01/05/2023] Open
Abstract
Ethyl acetate is an organic solvent with many industrial applications, currently produced by energy-intensive chemical processes based on fossil carbon resources. Ethyl acetate can be synthesized from renewable sugars by yeasts like Kluyveromyces marxianus in aerobic processes. However, ethyl acetate is highly volatile and thus stripped from aerated cultivation systems which complicate the quantification of the produced ester. Synthesis of volatile metabolites is commonly monitored by repeated analysis of metabolite concentrations in both the gas and liquid phase. In this study, a model-based method for quantifying the synthesis and degradation of volatile metabolites was developed. This quantification of volatiles is solely based on repeatedly measured gas-phase concentrations and allows calculation of reaction rates and yields in high temporal resolution. Parameters required for these calculations were determined in abiotic stripping tests. The developed method was validated for ethyl acetate, ethanol and acetaldehyde which were synthesized by K. marxianus DSM 5422 during an iron-limited batch cultivation; it was shown that the presented method is more precise and less time-consuming than the conventional method. The biomass-specific synthesis rate and the yield of ethyl acetate varied over time and exhibited distinct momentary maxima of 0.50 g g‒1h‒1 and 0.38 g g‒1 at moderate iron limitation.
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Affiliation(s)
- Christian Löser
- Chair of Bioprocess Engineering, Institute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Christian Kupsch
- Chair of Bioprocess Engineering, Institute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Thomas Walther
- Chair of Bioprocess Engineering, Institute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Andreas Hoffmann
- Chair of Bioprocess Engineering, Institute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
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Hoffmann A, Kupsch C, Walther T, Löser C. Synthesis of ethyl acetate from glucose by Kluyveromyces marxianus, Cyberlindnera jadinii and Wickerhamomyces anomalus depending on the induction mode. Eng Life Sci 2021; 21:154-168. [PMID: 33716614 PMCID: PMC7923572 DOI: 10.1002/elsc.202000048] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 10/28/2020] [Accepted: 11/12/2020] [Indexed: 11/17/2022] Open
Abstract
Ethyl acetate is currently produced from fossil carbon resources. This ester could also be microbially synthesized from sugar-rich wastes of the food industry. Wild-type strains with GRAS status are preferred for such applications. Production of ethyl acetate by wild-type yeasts has been repeatedly reported, but comparative studies with several strains at various induction modes are largely missing. Here, synthesis of ethyl acetate by three yeasts with GRAS status, Kluyveromyces marxianus DSM 5422, Cyberlindnera jadinii DSM 2361 and Wickerhamomyces anomalus DSM 6766, was studied under identical and well-defined conditions in an aerated bioreactor, by inducing the ester synthesis via iron or oxygen limitation. Balancing the ester synthesis was based on measured concentrations of ethyl acetate in the exhaust gas, delivering masses of synthesized ester and synthesis rates in a high temporal resolution. All tested yeasts synthesized ethyl acetate under these conditions, but the intensity varied with the strain and induction mode. The highest yields were achieved under iron limitation with K. marxianus (0.182 g g-1) and under oxygen limitation with W. anomalus (0.053 g g-1). Iron limitation proved to be the better inducer for ester synthesis while oxygen limitation favored ethanol formation. K. marxianus DSM 5422 was the most potent producer of ethyl acetate exhibiting the highest biomass-specific synthesis rate of 0.5 g g-1h-1 under moderate iron limitation.
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Affiliation(s)
- Andreas Hoffmann
- Chair of Bioprocess EngineeringInstitute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Christian Kupsch
- Chair of Bioprocess EngineeringInstitute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Thomas Walther
- Chair of Bioprocess EngineeringInstitute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Christian Löser
- Chair of Bioprocess EngineeringInstitute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
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Li X, Dai L, Liu H, Liu W, Pan B, Wang X, Deng J, Wang C, Zhang D, Li Z. Molecular mechanisms of furanone production through the EMP and PP pathways in Zygosaccharomyces rouxii with D-fructose addition. Food Res Int 2020; 133:109137. [PMID: 32466928 DOI: 10.1016/j.foodres.2020.109137] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 02/22/2020] [Accepted: 02/29/2020] [Indexed: 10/24/2022]
Abstract
4-Hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) and 4-hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3(2H)-furanone (HEMF) are important aroma chemicals in fermented foods. In this study, transcriptomics, qRT-PCR and enzymology methods were used to study the molecular mechanisms of furanone production through the Embden-Meyerhof-Parnas (EMP) and Pentose Phosphate (PP) pathways in Zygosaccharomyces rouxii based on the results of our previous study. The results indicated that D-fructose addition could significantly enhance Z. rouxii biomass production. In addition, HDMF and HEMF production was increased as a result of D-fructose addition based on HPLC analysis. The significant pathways for furanone synthesis were EMP (zro00010) and PP (zro00030) based on KEGG analysis. At the mRNA level, the differentially expressed genes involved in HDMF and HEMF biosynthesis were HK, PFK1, G6PI, FBA, TPI, 6GPL, TKT, and 6PGDH. Transient overexpression of FBA and 6PGDH in Z. rouxii was significantly increased during furanone production. FBA can regulate the accumulation of dihydroxyacetone phosphate (DHAP), which is one of the precursors of HDMF, while 6PGDH can regulate the accumulation of ribulose-5-phosphate, a precursor of HEMF. In addition, the activities of PFK1, FBA, and 6PGDH were significantly correlated with furanone production. LC-MS/MS results indicated that the primary metabolites for furanone synthesis in the EMP and PP pathways gradually increased with the consumption of D-fructose. These data demonstrate that D-fructose addition can be used to generate furanones through the EMP and PP pathways in Z. rouxii.
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Affiliation(s)
- Xin Li
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing 163319, China
| | - Lingyan Dai
- Department of Bioscience, College of Science and Biotechnology, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing 163319, China.
| | - Hong Liu
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing 163319, China
| | - Wei Liu
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing 163319, China
| | - Bailing Pan
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing 163319, China
| | - Xin Wang
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing 163319, China
| | - Jingzhi Deng
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing 163319, China
| | - Chengtao Wang
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology & Business University (BTBU), Beijing 100048, China
| | - Dongjie Zhang
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing 163319, China.
| | - Zhijiang Li
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing 163319, China.
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Liu H, Dai L, Wang F, Li X, Liu W, Pan B, Wang C, Zhang D, Deng J, Li Z. A new understanding: Gene expression, cell characteristic and antioxidant enzymes of Zygosaccharomyces rouxii under the D-fructose regulation. Enzyme Microb Technol 2019; 132:109409. [PMID: 31731962 DOI: 10.1016/j.enzmictec.2019.109409] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 08/11/2019] [Accepted: 08/14/2019] [Indexed: 11/17/2022]
Abstract
Zygosaccharomyces rouxii is a well-known salt-tolerant yeast. In our previous study, it was interesting that Z. rouxii could produce higher levels of 4-hydroxy-2, 5-dimethyl-3(2 H)-furanone in 120 g/L D-fructose and 180 g/L NaCl involved YPD medium at 5 d. In order to explore the resistance and furanone production mechanisms of Z. rouxii under D-fructose regulation, a comparative transcriptomics method in Z. rouxii was to set to find differentially expressed genes, the physiological and biochemical indexes (growth and cell morphology, lipid peroxidation and relative electrical conductivity, the antioxidant enzymes activity), and the expression of oxidoreductase activity genes. The results indicated that a larger number of different expressed genes at transcriptome analysis, such as the series antioxidant enzymes were related to the resistance characteristics. Research had confirmed that the living cell numbers and cell areas of D-fructose regulation group were significantly lower than the controls at the initial stage, while those higher than of the controls at the late stage. During the fermentation period, the lipid peroxidation and the relative electrical conductivity of the yeast cell membrane were increased. And also the D-fructose regulation group present lower inhibition superoxide anion ability. The activity of CAT in the D-fructose regulation group was always higher than that of the control group. Only the activity of GSH-Px was found to be significantly increased at 1 d except for other enzymes activities. Most of the oxidoreductase activity genes, such as especially the GSH-Px gene under D-fructose regulation conditions were expressed at higher levels than those of control groups. Combining the levels of transcription and enzymes activity data, those could understand that exogenous D-fructose had a stress effect on Z. rouxii at the early stage of culture. With the fermentation time progress, it was no longer a stressor substance for the Z. rouxii, and changed the nutrient to promote growth of Z. rouxii in the later stages. During the whole process, GSH-Px was the main defense enzyme and CAT was the sustained defense enzyme. Therefore, the experimental results might provide effective mechanisms in Z. rouxii for practical application of furanone production in the industry under exogenous D-fructose regulation.
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Affiliation(s)
- Hong Liu
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing, 163319, China
| | - Lingyan Dai
- Department of Bioscience, College of Science and Biotechnology, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing, 163319, China.
| | - Fanyu Wang
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing, 163319, China
| | - Xin Li
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing, 163319, China
| | - Wei Liu
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing, 163319, China
| | - Bailing Pan
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing, 163319, China
| | - Chengtao Wang
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology & Business University (BTBU), Beijing, 100048, China
| | - Dongjie Zhang
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing, 163319, China.
| | - Jingzhi Deng
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing, 163319, China
| | - Zhijiang Li
- Department of Food and Engineering, College of Food, Heilongjiang Bayi Agricultural University, Heilongjiang, Daqing, 163319, China.
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de Andrade Silva CA, Oka ML, Fonseca GG. Physiology of yeast strains isolated from Brazilian biomes in a minimal medium using fructose as the sole carbon source reveals potential biotechnological applications. 3 Biotech 2019; 9:191. [PMID: 31065491 DOI: 10.1007/s13205-019-1721-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Accepted: 04/17/2019] [Indexed: 01/06/2023] Open
Abstract
The aim of this study was to evaluate the kinetic parameters and the production of metabolites of 13 novel yeasts isolated from a distillery and fruits, and Saccharomyces cerevisiae CAT-1, cultivated in fructose-based medium. The yeasts with the highest µ max were obtained from must, Pichia kudriavzevii BB2, P. kudriavzevii BB1, and S. cerevisiae BB9 (0.47-0.49 h-1). S. cerevisiae CAT-1 (3.02 g gDCM-1 h-1), S. cerevisiae BB9 (3.01 g gDCM-1 h-1), and Candida glabrata Recol 41 (2.52 g gDCM-1 h-1) stood out in terms of µ S. C. parapsilosis Recol 29, and Rhodotorula mucilaginosa Recol 03 strains showed the highest Y X/S (0.30 and 0.28 gDCM g-1, respectively). C. glabrata Recol 10 and S. cerevisiae BB9 strains stood out for their higher substrate conversion rates into ethanol (0.44 and 0.41 gEth gS-1, respectively). R. mucilaginosa Recol 03 presented the poorest performance in substrate consumption (0.87 g gDCM-1 h-1), while the strains isolated from must and C. glabrata Recol 10 showed the highest ethanol production and the C. parapsilosis Recol 29 showed the highest biomass conversion.
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Bae JH, Kim HJ, Kim MJ, Sung BH, Jeon JH, Kim HS, Jin YS, Kweon DH, Sohn JH. Direct fermentation of Jerusalem artichoke tuber powder for production of l -lactic acid and d -lactic acid by metabolically engineered Kluyveromyces marxianus. J Biotechnol 2018; 266:27-33. [DOI: 10.1016/j.jbiotec.2017.12.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 09/22/2017] [Accepted: 12/01/2017] [Indexed: 10/18/2022]
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Transcriptome analysis of the thermotolerant yeast Kluyveromyces marxianus CCT 7735 under ethanol stress. Appl Microbiol Biotechnol 2017; 101:6969-6980. [DOI: 10.1007/s00253-017-8432-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 07/11/2017] [Accepted: 07/19/2017] [Indexed: 12/11/2022]
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15
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Liu JJ, Zhang GC, Oh EJ, Pathanibul P, Turner TL, Jin YS. Lactose fermentation by engineered Saccharomyces cerevisiae capable of fermenting cellobiose. J Biotechnol 2016; 234:99-104. [DOI: 10.1016/j.jbiotec.2016.07.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 07/20/2016] [Accepted: 07/22/2016] [Indexed: 11/26/2022]
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16
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Gombert AK, Madeira JV, Cerdán ME, González-Siso MI. Kluyveromyces marxianus as a host for heterologous protein synthesis. Appl Microbiol Biotechnol 2016; 100:6193-6208. [PMID: 27260286 DOI: 10.1007/s00253-016-7645-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 05/22/2016] [Accepted: 05/25/2016] [Indexed: 01/08/2023]
Abstract
The preferentially respiring and thermotolerant yeast Kluyveromyces marxianus is an emerging host for heterologous protein synthesis, surpassing the traditional preferentially fermenting yeast Saccharomyces cerevisiae in some important aspects: K . marxianus can grow at temperatures 10 °C higher than S. cerevisiae, which may result in decreased costs for cooling bioreactors and reduced contamination risk; has ability to metabolize a wider variety of sugars, such as lactose and xylose; is the fastest growing eukaryote described so far; and does not require special cultivation techniques (such as fed-batch) to avoid fermentative metabolism. All these advantages exist together with a high secretory capacity, performance of eukaryotic post-translational modifications, and with a generally regarded as safe (GRAS) status. In the last years, replication origins from several Kluyveromyces spp. have been used for the construction of episomal vectors, and also integrative strategies have been developed based on the tendency for non-homologous recombination displayed by K. marxianus. The recessive URA3 auxotrophic marker and the dominant Kan(R) are mostly used for selection of transformed cells, but other markers have been made available. Homologous and heterologous promoters and secretion signals have been characterized, with the K. marxianus INU1 expression and secretion system being of remarkable functionality. The efficient synthesis of roughly 50 heterologous proteins has been demonstrated, including one thermophilic enzyme. In this mini-review, we summarize the physiological characteristics of K. marxianus relevant for its use in the efficient synthesis of heterologous proteins, the efforts performed hitherto in the development of a molecular toolbox for this purpose, and some successful examples.
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Affiliation(s)
- Andreas K Gombert
- School of Food Engineering, University of Campinas, Rua Monteiro Lobato, 80, Campinas, SP, 13083-862, Brazil
| | - José Valdo Madeira
- School of Food Engineering, University of Campinas, Rua Monteiro Lobato, 80, Campinas, SP, 13083-862, Brazil
| | - María-Esperanza Cerdán
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía Celular e Molecular, Facultade de Ciencias, Universidade da Coruña, Campus de A Coruña, 15071, A Coruña, Spain
| | - María-Isabel González-Siso
- Grupo EXPRELA, Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Bioloxía Celular e Molecular, Facultade de Ciencias, Universidade da Coruña, Campus de A Coruña, 15071, A Coruña, Spain.
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Martynova J, Kokina A, Kibilds J, Liepins J, Scerbaka R, Vigants A. Effects of acetate on Kluyveromyces marxianus DSM 5422 growth and metabolism. Appl Microbiol Biotechnol 2016; 100:4585-94. [DOI: 10.1007/s00253-016-7392-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 02/09/2016] [Accepted: 02/11/2016] [Indexed: 10/22/2022]
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Dynamics of yeast immobilized-cell fluidized-bed bioreactors systems in ethanol fermentation from lactose-hydrolyzed whey and whey permeate. Bioprocess Biosyst Eng 2015; 39:141-50. [PMID: 26527573 DOI: 10.1007/s00449-015-1498-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 10/26/2015] [Indexed: 10/22/2022]
Abstract
We studied the dynamics of ethanol production on lactose-hydrolyzed whey (LHW) and lactose-hydrolyzed whey permeate (LHWP) in batch fluidized-bed bioreactors using single and co-cultures of immobilized cells of industrial strains of Saccharomyces cerevisiae and non-industrial strains of Kluyveromyces marxianus. Although the co-culture of S. cerevisiae CAT-1 and K. marxianus CCT 4086 produced two- to fourfold the ethanol productivity of single cultures of S. cerevisiae, the single cultures of the K. marxianus CCT 4086 produced the best results in both media (Y EtOH/S = 0.47-0.49 g g(-1) and Q P = 1.39-1.68 g L(-1) h(-1), in LHW and LHWP, respectively). Ethanol production on concentrated LHWP (180 g L(-1)) reached 79.1 g L(-1), with yields of 0.46 g g(-1) for K. marxianus CCT 4086 cultures. Repeated batches of fluidized-bed bioreactor on concentrated LHWP led to increased ethanol productivity, reaching 2.8 g L(-1) h(-1).
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Cheese whey: A potential resource to transform into bioprotein, functional/nutritional proteins and bioactive peptides. Biotechnol Adv 2015; 33:756-74. [PMID: 26165970 DOI: 10.1016/j.biotechadv.2015.07.002] [Citation(s) in RCA: 187] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 06/12/2015] [Accepted: 07/06/2015] [Indexed: 12/26/2022]
Abstract
The byproduct of cheese-producing industries, cheese whey, is considered as an environmental pollutant due to its high BOD and COD concentrations. The high organic load of whey arises from the presence of residual milk nutrients. As demand for milk-derived products is increasing, it leads to increased production of whey, which poses a serious management problem. To overcome this problem, various technological approaches have been employed to convert whey into value-added products. These technological advancements have enhanced whey utilization and about 50% of the total produced whey is now transformed into value-added products such as whey powder, whey protein, whey permeate, bioethanol, biopolymers, hydrogen, methane, electricity bioprotein (single cell protein) and probiotics. Among various value-added products, the transformation of whey into proteinaceous products is attractive and demanding. The main important factor which is attractive for transformation of whey into proteinaceous products is the generally recognized as safe (GRAS) regulatory status of whey. Whey and whey permeate are biotransformed into proteinaceous feed and food-grade bioprotein/single cell protein through fermentation. On the other hand, whey can be directly processed to obtain whey protein concentrate, whey protein isolate, and individual whey proteins. Further, whey proteins are also transformed into bioactive peptides via enzymatic or fermentation processes. The proteinaceous products have applications as functional, nutritional and therapeutic commodities. Whey characteristics, and its transformation processes for proteinaceous products such as bioproteins, functional/nutritional protein and bioactive peptides are covered in this review.
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Contreras A, Hidalgo C, Schmidt S, Henschke PA, Curtin C, Varela C. The application of non-Saccharomyces yeast in fermentations with limited aeration as a strategy for the production of wine with reduced alcohol content. Int J Food Microbiol 2015; 205:7-15. [PMID: 25866906 DOI: 10.1016/j.ijfoodmicro.2015.03.027] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 03/10/2015] [Accepted: 03/24/2015] [Indexed: 10/23/2022]
Abstract
High alcohol concentrations reduce the complexity of wine sensory properties. In addition, health and economic drivers have the wine industry actively seeking technologies that facilitate the production of wines with lower alcohol content. One of the simplest approaches to achieve this aim would be the use of wine yeast strains which are less efficient at transforming grape sugars into ethanol, however commercially available wine yeasts produce very similar ethanol yields. Non-conventional yeast, in particular non-Saccharomyces species, have shown potential for producing wines with lower alcohol content. These yeasts are naturally present in the early stages of fermentation but in general are not capable of completing alcoholic fermentation. We have evaluated 48 non-Saccharomyces isolates to identify strains that, with limited aeration and in sequential inoculation regimes with S. cerevisiae, could be used for the production of wine with lower ethanol concentration. Two of these, Torulaspora delbrueckii AWRI1152 and Zygosaccharomyces bailii AWRI1578, enabled the production of wine with reduced ethanol concentration under limited aerobic conditions. Depending on the aeration regime T. delbrueckii AWRI1152 and Z. bailii AWRI1578 showed a reduction in ethanol concentration of 1.5% (v/v) and 2.0% (v/v) respectively, compared to the S. cerevisiae anaerobic control.
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Affiliation(s)
- A Contreras
- The Australian Wine Research Institute, PO Box 197, Glen Osmond, Adelaide, South Australia, 5064, Australia; Department of Chemical and Bioprocess Engineering, College of Engineering, Pontificia Universidad Católica de Chile, Casilla 306 Correo 22, Santiago, Chile
| | - C Hidalgo
- The Australian Wine Research Institute, PO Box 197, Glen Osmond, Adelaide, South Australia, 5064, Australia; Instituto de Investigaciones Agropecuarias, La Platina Research Station, Avenida Santa Rosa 11610, La Pintana, 8831314, Santiago, Chile
| | - S Schmidt
- The Australian Wine Research Institute, PO Box 197, Glen Osmond, Adelaide, South Australia, 5064, Australia
| | - P A Henschke
- The Australian Wine Research Institute, PO Box 197, Glen Osmond, Adelaide, South Australia, 5064, Australia; School of Agriculture, Food and Wine, The University of Adelaide, PMB 1, Glen Osmond, SA 5064, Australia
| | - C Curtin
- The Australian Wine Research Institute, PO Box 197, Glen Osmond, Adelaide, South Australia, 5064, Australia
| | - C Varela
- The Australian Wine Research Institute, PO Box 197, Glen Osmond, Adelaide, South Australia, 5064, Australia.
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Kuloyo OO, du Preez JC, García-Aparicio MDP, Kilian SG, Steyn L, Görgens J. Opuntia ficus-indica cladodes as feedstock for ethanol production by Kluyveromyces marxianus and Saccharomyces cerevisiae. World J Microbiol Biotechnol 2014; 30:3173-83. [PMID: 25248867 PMCID: PMC4210634 DOI: 10.1007/s11274-014-1745-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 09/17/2014] [Indexed: 11/05/2022]
Abstract
The feasibility of ethanol production using an enzymatic hydrolysate of pretreated cladodes of Opuntia ficus-indica (prickly pear cactus) as carbohydrate feedstock was investigated, including a comprehensive chemical analysis of the cladode biomass and the effects of limited aeration on the fermentation profiles and sugar utilization. The low xylose and negligible mannose content of the cladode biomass used in this study suggested that the hemicellulose structure of the O. ficus-indica cladode was atypical of hardwood or softwood hemicelluloses. Separate hydrolysis and fermentation and simultaneous saccharification and fermentation procedures using Kluyveromyces marxianus and Saccharomyces cerevisiae at 40 and 35 °C, respectively, gave similar ethanol yields under non-aerated conditions. In oxygen-limited cultures K. marxianus exhibited almost double the ethanol productivity compared to non-aerated cultures, although after sugar depletion utilization of the produced ethanol was evident. Ethanol concentrations of up to 19.5 and 20.6 g l−1 were obtained with K. marxianus and S. cerevisiae, respectively, representing 66 and 70 % of the theoretical yield on total sugars in the hydrolysate. Because of the low xylan content of the cladode biomass, a yeast capable of xylose fermentation might not be a prerequisite for ethanol production. K. marxianus, therefore, has potential as an alternative to S. cerevisiae for bioethanol production. However, the relatively low concentration of fermentable sugars in the O. ficus-indica cladode hydrolysate presents a technical constraint for commercial exploitation.
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Affiliation(s)
- Olukayode O Kuloyo
- Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, P.O. Box 339, Bloemfontein, 9300, South Africa
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22
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Tofalo R, Fasoli G, Schirone M, Perpetuini G, Pepe A, Corsetti A, Suzzi G. The predominance, biodiversity and biotechnological properties of Kluyveromyces marxianus in the production of Pecorino di Farindola cheese. Int J Food Microbiol 2014; 187:41-9. [DOI: 10.1016/j.ijfoodmicro.2014.06.029] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 06/26/2014] [Accepted: 06/29/2014] [Indexed: 10/25/2022]
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23
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Banerjee S, Sarkar P, Turner AP. Amperometric biosensor based on Prussian Blue nanoparticle-modified screen-printed electrode for estimation of glucose-6-phosphate. Anal Biochem 2013; 439:194-200. [DOI: 10.1016/j.ab.2013.04.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 04/22/2013] [Accepted: 04/23/2013] [Indexed: 11/29/2022]
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24
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Yuan W, Zhao X, Chen L, Bai F. Improved ethanol production in Jerusalem artichoke tubers by overexpression of inulinase gene in Kluyveromyces marxianus. BIOTECHNOL BIOPROC E 2013. [DOI: 10.1007/s12257-013-0026-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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25
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Fonseca GG, de Carvalho NMB, Gombert AK. Growth of the yeast Kluyveromyces marxianus CBS 6556 on different sugar combinations as sole carbon and energy source. Appl Microbiol Biotechnol 2013; 97:5055-67. [PMID: 23435899 DOI: 10.1007/s00253-013-4748-6] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 01/31/2013] [Accepted: 01/31/2013] [Indexed: 12/01/2022]
Abstract
The yeast Kluyveromyces marxianus has been pointed out as a promising microorganism for a variety of industrial bioprocesses. Although genetic tools have been developed for this yeast and different potential applications have been investigated, quantitative physiological studies have rarely been reported. Here, we report and discuss the growth, substrate consumption, metabolite formation, and respiratory parameters of K. marxianus CBS 6556 during aerobic batch bioreactor cultivations, using a defined medium with different sugars as sole carbon and energy source, at 30 and 37 °C. Cultivations were carried out both on single sugars and on binary sugar mixtures. Carbon balances closed within 95 to 101 % in all experiments. Biomass and CO2 were the main products of cell metabolism, whereas by-products were always present in very low proportion (<3 % of the carbon consumed), as long as full aerobiosis was guaranteed. On all sugars tested as sole carbon and energy source (glucose, fructose, sucrose, lactose, and galactose), the maximum specific growth rate remained between 0.39 and 0.49 h(-1), except for galactose at 37 °C, which only supported growth at 0.31 h(-1). Different growth behaviors were observed on the binary sugar mixtures investigated (glucose and lactose, glucose and galactose, lactose and galactose, glucose and fructose, galactose and fructose, fructose and lactose), and the observations were in agreement with previously published data on the sugar transport systems in K. marxianus. We conclude that K. marxianus CBS 6556 does not present any special nutritional requirements; grows well in the range of 30 to 37 °C on different sugars; is capable of growing on sugar mixtures in a shorter period of time than Saccharomyces cerevisiae, which is interesting from an industrial point of view; and deviates tiny amounts of carbon towards metabolite formation, as long as full aerobiosis is maintained.
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Affiliation(s)
- Gustavo Graciano Fonseca
- Department of Chemical Engineering, University of São Paulo, PO Box 61548, CEP 05424-970 São Paulo, SP, Brazil
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26
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Formation of ethyl acetate from whey by Kluyveromyces marxianus on a pilot scale. J Biotechnol 2013; 163:17-23. [DOI: 10.1016/j.jbiotec.2012.10.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 10/10/2012] [Accepted: 10/12/2012] [Indexed: 11/18/2022]
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27
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Leite FCB, Basso TO, Pita WDB, Gombert AK, Simões DA, de Morais MA. Quantitative aerobic physiology of the yeast Dekkera bruxellensis, a major contaminant in bioethanol production plants. FEMS Yeast Res 2012; 13:34-43. [PMID: 23078341 DOI: 10.1111/1567-1364.12007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 08/07/2012] [Accepted: 09/07/2012] [Indexed: 12/01/2022] Open
Abstract
Dekkera bruxellensis has been described as the major contaminant yeast of industrial ethanol production, although little is known about its physiology. The aim of this study was to investigate the growth of this yeast in diverse carbon sources and involved conducting shake-flask and glucose- or sucrose-limited chemostats experiments, and from the chemostat data, the stoichiometry of biomass formation during aerobic growth was established. As a result of the shake-flask experiments with hexoses or disaccharides, the specific growth rates were calculated, and a different behavior in rich and mineral medium was observed concerning to profile of acetate and ethanol production. In C-limited chemostats conditions, the metabolism of this yeast was completely respiratory, and the biomass yields reached values of 0.62 gDW gS(-1) . In addition, glucose pulses were applied to the glucose- or sucrose-limited chemostats. These results showed that D. bruxellensis has a short-term Crabtree effect. While the glucose pulse was at the sucrose-limited chemostat, sucrose accumulated at the reactor, indicating the presence of a glucose repression mechanism in D. bruxellensis.
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Formation of ethyl acetate by Kluyveromyces marxianus on whey during aerobic batch and chemostat cultivation at iron limitation. Appl Microbiol Biotechnol 2012; 96:685-96. [PMID: 22695802 DOI: 10.1007/s00253-012-4205-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 05/22/2012] [Accepted: 05/22/2012] [Indexed: 10/28/2022]
Abstract
The ability of Kluyveromyces marxianus to convert lactose into ethyl acetate offers a chance for an economic reuse of whey. Former experiments with K. marxianus DSM 5422 proved limitation of growth by iron (Fe) or copper as a precondition for significant ester synthesis. Several aerobic batch and chemostat cultivations were done with whey-borne media of a variable Fe content for exploring the effect of Fe on growth, the Fe content of biomass, and metabolite synthesis. At low Fe doses, Fe was the growth-limiting factor, the available Fe was completely absorbed by the yeasts, and the biomass formation linearly depended on the Fe dose governed by a minimum Fe content in the yeasts, x (Fe,min). At batch conditions, x (Fe,min) was 8.8 μg/g, while during chemostat cultivation at D = 0.15 h(-1), it was 23 μg/g. At high Fe doses, sugar was the growth-limiting factor, Fe was more or less absorbed, and the formed biomass became constant. Significant amounts of ethyl acetate were only formed at Fe limitation while high Fe doses suppressed ester formation. Analysis of formed metabolites such as glycerol, pyruvate, acetate, ethanol, ethyl acetate, isocitrate, 2-oxoglutarate, succinate, and malate during chemostat cultivation allowed some interpretation of the Fe-dependent mechanism of ester synthesis; formation of ethyl acetate from acetyl-SCoA and ethanol is obviously initiated by a diminished metabolic flux of acetyl-SCoA into the citrate cycle and by a limited oxidation of NADH in the respiratory chain since Fe is required for the function of aconitase, succinate dehydrogenase, and the electron-transferring proteins.
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Matsuzaki C, Nakagawa A, Koyanagi T, Tanaka K, Minami H, Tamaki H, Katayama T, Yamamoto K, Kumagai H. Kluyveromyces marxianus-based platform for direct ethanol fermentation and recovery from cellulosic materials under air-ventilated conditions. J Biosci Bioeng 2012; 113:604-7. [DOI: 10.1016/j.jbiosc.2011.12.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 12/08/2011] [Accepted: 12/13/2011] [Indexed: 10/14/2022]
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The high fermentative metabolism of Kluyveromyces marxianus UFV-3 relies on the increased expression of key lactose metabolic enzymes. Antonie van Leeuwenhoek 2011; 101:541-50. [DOI: 10.1007/s10482-011-9668-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Accepted: 10/24/2011] [Indexed: 10/15/2022]
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Rocha SN, Abrahão-Neto J, Gombert AK. Physiological diversity within the Kluyveromyces marxianus species [corrected]. Antonie van Leeuwenhoek 2011; 100:619-30. [PMID: 21732033 DOI: 10.1007/s10482-011-9617-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Accepted: 06/21/2011] [Indexed: 11/30/2022]
Abstract
The Kluyveromyces marxianus strains CBS 6556, CBS 397 and CBS 712(T) were cultivated on a defined medium with either glucose, lactose or sucrose as the sole carbon source, at 30 and 37°C. The aim of this work was to evaluate the diversity within this species, in terms of the macroscopic physiology. The main properties evaluated were: intensity of the Crabtree effect, specific growth rate, biomass yield on substrate, metabolite excretion and protein secretion capacity, inferred by measuring extracellular inulinase activity. The strain Kluyveromyces lactis CBS 2359 was evaluated in parallel, since it is the best described Kluyveromyces yeast and thus can be used as a control for the experimental setup. K. marxianus CBS 6556 presented the highest specific growth rate (0.70 h(-1)) and the highest specific inulinase activity (1.65 U mg(-1) dry cell weight) among all strains investigated, when grown at 37°C with sucrose as the sole carbon source. The lowest metabolite formation and highest biomass yield on substrate (0.59 g dry cell weight g sucrose(-1)) was achieved by K. marxianus CBS 712(T) at 37°C. Taken together, the results show a systematic comparison of carbon and energy metabolism among three of the best known K. marxianus strains, in parallel to K. lactis CBS 2359.
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Affiliation(s)
- Saul Nitsche Rocha
- Department of Chemical Engineering, University of São Paulo, São Paulo, SP, Brazil.
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32
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Growth and ethanol fermentation ability on hexose and pentose sugars and glucose effect under various conditions in thermotolerant yeast Kluyveromyces marxianus. Appl Microbiol Biotechnol 2011; 90:1573-86. [PMID: 21476140 DOI: 10.1007/s00253-011-3218-2] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Revised: 02/13/2011] [Accepted: 02/24/2011] [Indexed: 10/18/2022]
Abstract
Ethanol fermentation ability of the thermotolerant yeast Kluyveromyces marxianus, which is able to utilize various sugars including glucose, mannose, galactose, xylose, and arabinose, was examined under shaking and static conditions at high temperatures. The yeast was found to produce ethanol from all of these sugars except for arabinose under a shaking condition but only from hexose sugars under a static condition. Growth and sugar utilization rate under a static condition were slower than those under a shaking condition, but maximum ethanol yield was slightly higher. Even at 40°C, a level of ethanol production similar to that at 30°C was observed except for galactose under a static condition. Glucose repression on utilization of other sugars was observed, and it was more evident at elevated temperatures. Consistent results were obtained by the addition of 2-deoxyglucose. The glucose effect was further examined at a transcription level, and it was found that KmGAL1 for galactokinase and KmXYL1 for xylose reductase for galactose and xylose/arabinose utilization, respectively, were repressed by glucose at low and high temperatures, but KmHXK2 for hexokinase was not repressed. We discuss the possible mechanism of glucose repression and the potential for utilization of K. marxianus in high-temperature fermentation with mixed sugars containing glucose.
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Rocha SN, Abrahão-Neto J, Cerdán ME, Gombert AK, González-Siso MI. Heterologous expression of a thermophilic esterase in Kluyveromyces yeasts. Appl Microbiol Biotechnol 2010; 89:375-85. [PMID: 20862582 DOI: 10.1007/s00253-010-2869-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 08/13/2010] [Accepted: 09/07/2010] [Indexed: 11/26/2022]
Abstract
In the present work, a thermophilic esterase from Thermus thermophilus HB27 was cloned into Kluyveromyces marxianus and into Kluyveromyces lactis using two different expression systems, yielding four recombinant strains. K. lactis showed the highest esterase expression levels (294 units per gram dry cell weight, with 65% of cell-bound enzyme) using an episomal system with the PGK promoter and terminator from Saccharomyces cerevisiae combined with the K. lactis k1 secretion signal. K. marxianus showed higher secretion efficiency of the heterologous esterase (56.9 units per gram dry cell weight, with 34% of cell-bound enzyme) than K. lactis. Hydrolytic activities for the heterologous esterases were maximum at pH values between 8.0 and 9.0 for both yeast species and at temperatures of 50 °C and 45 °C for K. marxianus and K. lactis, respectively. When compared to previously published data on this same esterase produced in the original host or in S. cerevisiae, our results indicate that Kluyveromyces yeasts can be considered good hosts for the heterologous secretion of thermophilic esterases, which have a potential application in biodiesel production or in resolving racemates.
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Affiliation(s)
- Saul Nitsche Rocha
- Department of Chemical Engineering, University of São Paulo, C.P. 61548, 05424-970 São Paulo, SP, Brazil.
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Trends and challenges in the microbial production of lignocellulosic bioalcohol fuels. Appl Microbiol Biotechnol 2010; 87:1303-15. [DOI: 10.1007/s00253-010-2707-z] [Citation(s) in RCA: 256] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 05/27/2010] [Accepted: 05/27/2010] [Indexed: 12/30/2022]
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Rocha SN, Abrahão-Neto J, Cerdán ME, González-Siso MI, Gombert AK. Heterologous expression of glucose oxidase in the yeast Kluyveromyces marxianus. Microb Cell Fact 2010; 9:4. [PMID: 20092622 PMCID: PMC2817671 DOI: 10.1186/1475-2859-9-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Accepted: 01/21/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In spite of its advantageous physiological properties for bioprocess applications, the use of the yeast Kluyveromyces marxianus as a host for heterologous protein production has been very limited, in constrast to its close relative Kluyveromyces lactis. In the present work, the model protein glucose oxidase (GOX) from Aspergillus niger was cloned into K. marxianus CBS 6556 and into K. lactis CBS 2359 using three different expression systems. We aimed at verifying how each expression system would affect protein expression, secretion/localization, post-translational modification, and biochemical properties. RESULTS The highest GOX expression levels (1552 units of secreted protein per gram dry cell weight) were achieved using an episomal system, in which the INU1 promoter and terminator were used to drive heterologous gene expression, together with the INU1 prepro sequence, which was employed to drive secretion of the enzyme. In all cases, GOX was mainly secreted, remaining either in the periplasmic space or in the culture supernatant. Whereas the use of genetic elements from Saccharomyces cerevisiae to drive heterologous protein expression led to higher expression levels in K. lactis than in K. marxianus, the use of INU1 genetic elements clearly led to the opposite result. The biochemical characterization of GOX confirmed the correct expression of the protein and showed that K. marxianus has a tendency to hyperglycosylate the protein, in a similar way as already observed for other yeasts, although this tendency seems to be smaller than the one of e.g. K. lactis and S. cerevisiae. Hyperglycosylation of GOX does not seem to affect its affinity for the substrate, nor its activity. CONCLUSIONS Taken together, our results indicate that K. marxianus is indeed a good host for the expression of heterologous proteins, not only for its physiological properties, but also because it correctly secretes and folds these proteins.
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Affiliation(s)
- Saul N Rocha
- Department of Chemical Engineering, Polytechnic School of Engineering, University of São Paulo, CP 61548, 05424-970 São Paulo-SP, Brazil
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Fai PB, Grant A. A comparative study of Saccharomyces cerevisiae sensitivity against eight yeast species sensitivities to a range of toxicants. CHEMOSPHERE 2009; 75:289-296. [PMID: 19185901 DOI: 10.1016/j.chemosphere.2008.12.059] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2008] [Revised: 11/13/2008] [Accepted: 12/16/2008] [Indexed: 05/27/2023]
Abstract
Fungi are widespread and very important in many ecosystems but the extensive use of pesticides can adversely affect beneficial fungi. The yeast, Saccharomyces cerevisiae has been proposed for the toxicological assessment of the effects of environmental pollutants on non-target fungi. To assess whether S. cerevisiae is a good representative of the immense ecological and phylogenetic diversity of yeasts, we compare the sensitivity of eight other yeasts from diverse phylogenetic taxa to a range of toxicants and environmental samples. Sensitivity was assessed using both the growth inhibition and alamar blue (resorufin fluorescence inhibition) bioassays. The growth inhibition bioassay showed that all yeast species had similar dose-response curves for the five organic fungicides and two environmental samples used. However, two yeast species, Trichosporon dulcitum and Pseudozyma fusiformata, were a great deal more sensitive than all others to CuSO4 and K2Cr2O7 while S. cerevisiae was the most tolerant to these chemicals. S. cerevisiae, however, showed similar sensitivity as other species to all toxicants in the resorufin fluorescence inhibition bioassay. It can therefore be used as a representative yeast species for assessing effects of environmental contaminants to non-target fungi and in the screening of chemical libraries for fungicidal activity.
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Affiliation(s)
- Patricia Bi Fai
- Centre for Ecology, Evolution and Conservation (CEEC), School of Environmental Sciences, University of East Anglia, Norwich NR47TJ, UK.
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Fonseca GG, Heinzle E, Wittmann C, Gombert AK. The yeast Kluyveromyces marxianus and its biotechnological potential. Appl Microbiol Biotechnol 2008; 79:339-54. [PMID: 18427804 DOI: 10.1007/s00253-008-1458-6] [Citation(s) in RCA: 307] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Revised: 03/12/2008] [Accepted: 03/13/2008] [Indexed: 11/26/2022]
Abstract
Strains belonging to the yeast species Kluyveromyces marxianus have been isolated from a great variety of habitats, which results in a high metabolic diversity and a substantial degree of intraspecific polymorphism. As a consequence, several different biotechnological applications have been investigated with this yeast: production of enzymes (beta-galactosidase, beta-glucosidase, inulinase, and polygalacturonases, among others), of single-cell protein, of aroma compounds, and of ethanol (including high-temperature and simultaneous saccharification-fermentation processes); reduction of lactose content in food products; production of bioingredients from cheese-whey; bioremediation; as an anticholesterolemic agent; and as a host for heterologous protein production. Compared to its congener and model organism, Kluyveromyces lactis, the accumulated knowledge on K. marxianus is much smaller and spread over a number of different strains. Although there is no publicly available genome sequence for this species, 20% of the CBS 712 strain genome was randomly sequenced (Llorente et al. in FEBS Lett 487:71-75, 2000). In spite of these facts, K. marxianus can envisage a great biotechnological future because of some of its qualities, such as a broad substrate spectrum, thermotolerance, high growth rates, and less tendency to ferment when exposed to sugar excess, when compared to K. lactis. To increase our knowledge on the biology of this species and to enable the potential applications to be converted into industrial practice, a more systematic approach, including the careful choice of (a) reference strain(s) by the scientific community, would certainly be of great value.
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Ribeiro O, Gombert AK, Teixeira JA, Domingues L. Application of the Cre-loxP system for multiple gene disruption in the yeast Kluyveromyces marxianus. J Biotechnol 2007; 131:20-6. [PMID: 17624462 DOI: 10.1016/j.jbiotec.2007.05.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2007] [Revised: 05/08/2007] [Accepted: 05/25/2007] [Indexed: 10/23/2022]
Abstract
The yeast Kluyveromyces marxianus presents several interesting features that make this species a promising industrial yeast for the production of several compounds. In order to take full advantage of this yeast and its particular properties, proper tools for gene disruption and metabolic engineering are needed. The Cre-loxP system is a very versatile tool that allows for gene marker rescue, resulting in mutant strains free of exogenous selective markers, which is a very important aspect for industrial application. As the Cre-loxP system works in some non-conventional yeasts, namely Kluyveromyces lactis, we wished to know whether it also works in K. marxianus. Here, we report the validation of this system in K. marxianus CBS 6556, by disrupting two copies of the LAC4 gene, which encodes a beta-galactosidase activity.
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Affiliation(s)
- Orquídea Ribeiro
- Institute of Biotechnology and Bioengineering (IBB), Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, Braga, Portugal
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The use of the GDH gene for molecular identification and phylogenetic analysis of the yeast Kluyveromyces marxianus. World J Microbiol Biotechnol 2006. [DOI: 10.1007/s11274-006-9141-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Wu L, van Dam J, Schipper D, Kresnowati MTAP, Proell AM, Ras C, van Winden WA, van Gulik WM, Heijnen JJ. Short-term metabolome dynamics and carbon, electron, and ATP balances in chemostat-grown Saccharomyces cerevisiae CEN.PK 113-7D following a glucose pulse. Appl Environ Microbiol 2006; 72:3566-77. [PMID: 16672504 PMCID: PMC1472385 DOI: 10.1128/aem.72.5.3566-3577.2006] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The in vivo kinetics in Saccharomyces cerevisiae CEN.PK 113-7D was evaluated during a 300-second transient period after applying a glucose pulse to an aerobic, carbon-limited chemostat culture. We quantified the responses of extracellular metabolites, intracellular intermediates in primary metabolism, intracellular free amino acids, and in vivo rates of O(2) uptake and CO(2) evolution. With these measurements, dynamic carbon, electron, and ATP balances were set up to identify major carbon, electron, and energy sinks during the postpulse period. There were three distinct metabolic phases during this time. In phase I (0 to 50 seconds after the pulse), the carbon/electron balances closed up to 85%. The accumulation of glycolytic and storage compounds accounted for 60% of the consumed glucose, caused an energy depletion, and may have led to a temporary decrease in the anabolic flux. In phase II (50 to 150 seconds), the fermentative metabolism gradually became the most important carbon/electron sink. In phase III (150 to 300 seconds), 29% of the carbon uptake was not identified in the measurements, and the ATP balance had a large surplus. These results indicate an increase in the anabolic flux, which is consistent with macroscopic balances of extracellular fluxes and the observed increase in CO(2) evolution associated with nonfermentative metabolism. The identified metabolic processes involving major carbon, electron, and energy sinks must be taken into account in in vivo kinetic models based on short-term dynamic metabolome responses.
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Affiliation(s)
- Liang Wu
- DSM Anti-Infectives, P.O. Box 525, 2613 AX Delft, The Netherlands.
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Rubio-Texeira M. A comparative analysis of the GAL genetic switch between not-so-distant cousins: Saccharomyces cerevisiae versus Kluyveromyces lactis. FEMS Yeast Res 2005; 5:1115-28. [PMID: 16014343 DOI: 10.1016/j.femsyr.2005.05.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2005] [Revised: 05/12/2005] [Accepted: 05/18/2005] [Indexed: 11/21/2022] Open
Abstract
Despite their close phylogenetic relationship, Kluyveromyces lactis and Saccharomyces cerevisiae have adapted their carbon utilization systems to different environments. Although they share identities in the arrangement, sequence and functionality of their GAL gene set, both yeasts have evolved important differences in the GAL genetic switch in accordance to their relative preference for the utilization of galactose as a carbon source. This review provides a comparative overview of the GAL-specific regulatory network in S. cerevisiae and K. lactis, discusses the latest models proposed to explain the transduction of the galactose signal, and describes some of the particularities that both microorganisms display in their regulatory response to different carbon sources. Emphasis is placed on the potential for improved strategies in biotechnological applications using yeasts.
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Affiliation(s)
- Marta Rubio-Texeira
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
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Blank LM, Lehmbeck F, Sauer U. Metabolic-flux and network analysis in fourteen hemiascomycetous yeasts. FEMS Yeast Res 2005; 5:545-58. [PMID: 15780654 DOI: 10.1016/j.femsyr.2004.09.008] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Revised: 09/28/2004] [Accepted: 09/29/2004] [Indexed: 12/01/2022] Open
Abstract
In a quantitative comparative study, we elucidated the glucose metabolism in fourteen hemiascomycetous yeasts from the Genolevures project. The metabolic networks of these different species were first established by (13)C-labeling data and the inventory of the genomes. This information was subsequently used for metabolic-flux ratio analysis to quantify the intracellular carbon flux distributions in these yeast species. Firstly, we found that compartmentation of amino acid biosynthesis in most species was identical to that in Saccharomyces cerevisiae. Exceptions were the mitochondrial origin of aspartate biosynthesis in Yarrowia lipolytica and the cytosolic origin of alanine biosynthesis in S. kluyveri. Secondly, the control of flux through the TCA cycle was inversely correlated with the ethanol production rate, with S. cerevisiae being the yeast with the highest ethanol production capacity. The classification between respiratory and respiro-fermentative metabolism, however, was not qualitatively exclusive but quantitatively gradual. Thirdly, the flux through the pentose phosphate (PP) pathway was correlated to the yield of biomass, suggesting a balanced production and consumption of NADPH. Generally, this implies the lack of active transhydrogenase-like activities in hemiascomycetous yeasts under the tested growth condition, with Pichia angusta as the sole exception. In the latter case, about 40% of the NADPH was produced in the PP pathway in excess of the requirements for biomass production, which strongly suggests the operation of a yet unidentified mechanism for NADPH reoxidation in this species. In most yeasts, the PP pathway activity appears to be driven exclusively by the demand for NADPH.
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Affiliation(s)
- Lars M Blank
- Institute of Biotechnology, Building HPT E58, ETH Zürich, 8093 Zürich, Switzerland.
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Current awareness on yeast. Yeast 2004; 21:1233-40. [PMID: 15580707 DOI: 10.1002/yea.1096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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