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Drozdova P, Gurkov A, Saranchina A, Vlasevskaya A, Zolotovskaya E, Indosova E, Timofeyev M, Borvinskaya E. Transcriptional response of Saccharomyces cerevisiae to lactic acid enantiomers. Appl Microbiol Biotechnol 2024; 108:121. [PMID: 38229303 DOI: 10.1007/s00253-023-12863-z] [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: 06/07/2023] [Revised: 10/16/2023] [Accepted: 10/24/2023] [Indexed: 01/18/2024]
Abstract
The model yeast, Saccharomyces cerevisiae, is a popular object for both fundamental and applied research, including the development of biosensors and industrial production of pharmaceutical compounds. However, despite multiple studies exploring S. cerevisiae transcriptional response to various substances, this response is unknown for some substances produced in yeast, such as D-lactic acid (DLA). Here, we explore the transcriptional response of the BY4742 strain to a wide range of DLA concentrations (from 0.05 to 45 mM), and compare it to the response to 45 mM L-lactic acid (LLA). We recorded a response to 5 and 45 mM DLA (125 and 113 differentially expressed genes (DEGs), respectively; > 50% shared) and a less pronounced response to 45 mM LLA (63 DEGs; > 30% shared with at least one DLA treatment). Our data did not reveal natural yeast promoters quantitatively sensing DLA but provide the first description of the transcriptome-wide response to DLA and enrich our understanding of the LLA response. Some DLA-activated genes were indeed related to lactate metabolism, as well as iron uptake and cell wall structure. Additional analyses showed that at least some of these genes were activated only by acidic form of DLA but not its salt, revealing the role of pH. The list of LLA-responsive genes was similar to those published previously and also included iron uptake and cell wall genes, as well as genes responding to other weak acids. These data might be instrumental for optimization of lactate production in yeast and yeast co-cultivation with lactic acid bacteria. KEY POINTS: • We present the first dataset on yeast transcriptional response to DLA. • Differential gene expression was correlated with yeast growth inhibition. • The transcriptome response to DLA was richer in comparison to LLA.
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Affiliation(s)
- Polina Drozdova
- Irkutsk State University, Karl-Marx Str. 1, Irkutsk, 664025, Russian Federation.
- Baikal Research Centre, Rabochaya Str. 5V, Irkutsk, 664011, Russian Federation.
| | - Anton Gurkov
- Irkutsk State University, Karl-Marx Str. 1, Irkutsk, 664025, Russian Federation
- Baikal Research Centre, Rabochaya Str. 5V, Irkutsk, 664011, Russian Federation
| | | | | | - Elena Zolotovskaya
- Irkutsk State University, Karl-Marx Str. 1, Irkutsk, 664025, Russian Federation
| | - Elizaveta Indosova
- Irkutsk State University, Karl-Marx Str. 1, Irkutsk, 664025, Russian Federation
| | - Maxim Timofeyev
- Irkutsk State University, Karl-Marx Str. 1, Irkutsk, 664025, Russian Federation
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Sánchez-Adriá IE, Sanmartín G, Prieto JA, Estruch F, Fortis E, Randez-Gil F. Adaptive laboratory evolution for acetic acid-tolerance matches sourdough challenges with yeast phenotypes. Microbiol Res 2023; 277:127487. [PMID: 37713908 DOI: 10.1016/j.micres.2023.127487] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/05/2023] [Accepted: 09/06/2023] [Indexed: 09/17/2023]
Abstract
Acetic acid tolerance of Saccharomyces cerevisiae is an important trait in sourdough fermentation processes, where the accumulation of acid by the growth of lactic acid bacteria reduces the yeast metabolic activity. In this work, we have carried out adaptive laboratory evolution (ALE) experiments in two sourdough isolates of S. cerevisiae exposed to acetic acid, or alternatively to acetic acid and myriocin, an inhibitor of sphingolipid biosynthesis that sped-up the evolutionary adaptation. Evolution approaches resulted in acetic tolerance, and surprisingly, increased lactic susceptibility. Four evolved clones, one from each parental strain and evolutionary scheme, were selected on the basis of their potential for CO2 production in sourdough conditions. Among them, two showed phenotypic instability characterized by strong lactic sensitivity after several rounds of growth under unstressed conditions, while two others, displayed increased constitutive acetic tolerance with no loss of growth in lactic medium. Genome sequencing and ploidy level analysis of all strains revealed aneuploidies, which could account for phenotypic heterogeneity. In addition, copy number variations (CNVs), affecting specially to genes involved in ion transport or flocculation, and single nucleotide polymorphisms (SNPs) were identified. Mutations in several genes, ARG82, KEX1, CTK1, SPT20, IRA2, ASG1 or GIS4, were confirmed as involved in acetic and/or lactic tolerance, and new determinants of these phenotypes, MSN5 and PSP2, identified.
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Affiliation(s)
- Isabel E Sánchez-Adriá
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Avda. Agustín Escardino, 7, Paterna, 46980 Valencia, Spain
| | - Gemma Sanmartín
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Avda. Agustín Escardino, 7, Paterna, 46980 Valencia, Spain
| | - Jose A Prieto
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Avda. Agustín Escardino, 7, Paterna, 46980 Valencia, Spain
| | - Francisco Estruch
- Department of Biochemistry and Molecular Biology, Universitat de València, Dr. Moliner 50, 46100 Burjassot, Spain
| | - Estefanía Fortis
- Cereal (Center for Research Europastry Advanced Lab), Europastry S.A., Marie Curie, 6, Sant Joan Despí, 08970 Barcelona, Spain
| | - Francisca Randez-Gil
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Avda. Agustín Escardino, 7, Paterna, 46980 Valencia, Spain.
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Robles-Iglesias R, Nicaud JM, Veiga MC, Kennes C. Integrated fermentative process for lipid and β-carotene production from acetogenic syngas fermentation using an engineered oleaginous Yarrowia lipolytica yeast. BIORESOURCE TECHNOLOGY 2023; 389:129815. [PMID: 37783238 DOI: 10.1016/j.biortech.2023.129815] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 09/29/2023] [Accepted: 09/29/2023] [Indexed: 10/04/2023]
Abstract
An engineered Yarrowia lipolytica strain was successfully employed to produce β-carotene and lipids from acetic acid, a product of syngas fermentation by Clostridium aceticum. The strain showed acetic acid tolerance up to concentrations of 20 g/L. Flask experiments yielded a peak lipid content of 33.7 % and β-carotene concentration of 13.6 mg/g under specific nutrient conditions. The study also investigated pH effects on production in bioreactors, revealing optimal lipid and β-carotene contents at pH 6.0, reaching 22.9 % and 44 mg/g, respectively. Lipid profiles were consistent across experiments, with C18:1 being the dominant compound at approximately 50 %. This research underscores a green revolution in bioprocessing, showing how biocatalysts can convert syngas, a potentially polluting byproduct, into valuable β-carotene and lipids with a Y. lipolytica strain.
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Affiliation(s)
- Raúl Robles-Iglesias
- Chemical Engineering Laboratory, Faculty of Sciences and Interdisciplinary Centre of Chemistry and Biology - Centro Interdisciplinar de Química y Biología (CICA), BIOENGIN Group, University of A Coruña, Rúa da Fraga 10, La Coruña 15008, Spain
| | - Jean-Marc Nicaud
- Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, 78350 Jouy-en-Josas, France
| | - María C Veiga
- Chemical Engineering Laboratory, Faculty of Sciences and Interdisciplinary Centre of Chemistry and Biology - Centro Interdisciplinar de Química y Biología (CICA), BIOENGIN Group, University of A Coruña, Rúa da Fraga 10, La Coruña 15008, Spain
| | - Christian Kennes
- Chemical Engineering Laboratory, Faculty of Sciences and Interdisciplinary Centre of Chemistry and Biology - Centro Interdisciplinar de Química y Biología (CICA), BIOENGIN Group, University of A Coruña, Rúa da Fraga 10, La Coruña 15008, Spain.
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Rezaei N, Seidi S, Fotouhi M. On-chip electromembrane extraction using deep eutectic solvent and red-green-blue analysis by quick-response code readable customized application on a smartphone for measuring salicylic acid in pharmaceutical and plasma samples. J Chromatogr A 2023; 1708:464347. [PMID: 37696125 DOI: 10.1016/j.chroma.2023.464347] [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: 06/05/2023] [Revised: 08/19/2023] [Accepted: 08/30/2023] [Indexed: 09/13/2023]
Abstract
The current work presents an on-chip electromembrane extraction (OC-EME) method using deep eutectic solvent followed by QR code-based red-green-blue (RGB) analysis for measuring salicylic acid (SA) in plasma and pharmaceutical samples. The RGB analysis was performed based on forming the SA-Fe3+ complex in the acceptor phase giving a purple solution. The QR code readable customized app provided rapid, easy, and cost-less qualification and quantification of SA with the aid of principal component analysis (PCA). Parameters affecting OC-EME, including the supported liquid membrane (SLM), pH of the donor and acceptor phases, applied voltage, and sample flow rate, were optimized. Also, the concentration of FeCl3, as a chromogenic reagent, and its reaction time with SA were investigated to find the best concentration-dependent signal. Under the optimized conditions, a good relationship was observed between the green intensity and SA concentration within the range of 1.0-100.0 mg l-1 (R2 = 0.9946) in water and 5.0-100.0 mg l-1 (R2 = 0.9902) in plasma. Intra- and inter-day RSDs% were obtained less than 4.7% and 7.7%, respectively. Finally, the method was successfully applied for measuring SA in foot corn treatment, Aspirin medicines, and human plasma, with relative recoveries between 89.0 and 129.2%.
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Affiliation(s)
- Neda Rezaei
- Department of Analytical Chemistry, Faculty of Chemistry, K.N. Toosi University of Technology, P.O. Box 16315-1618, Tehran 15418-49611, Iran; Nanomaterial, Separation and Trace Analysis Research Lab, K.N. Toosi University of Technology, P.O. Box 16315-1618, Tehran 15418-49611, Iran
| | - Shahram Seidi
- Department of Analytical Chemistry, Faculty of Chemistry, K.N. Toosi University of Technology, P.O. Box 16315-1618, Tehran 15418-49611, Iran; Nanomaterial, Separation and Trace Analysis Research Lab, K.N. Toosi University of Technology, P.O. Box 16315-1618, Tehran 15418-49611, Iran.
| | - Mina Fotouhi
- Department of Analytical Chemistry, Faculty of Chemistry, K.N. Toosi University of Technology, P.O. Box 16315-1618, Tehran 15418-49611, Iran; Nanomaterial, Separation and Trace Analysis Research Lab, K.N. Toosi University of Technology, P.O. Box 16315-1618, Tehran 15418-49611, Iran
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Gu Y, Zhang B, Tian J, Li L, He Y. Physiology, quorum sensing, and proteomics of lactic acid bacteria were affected by Saccharomyces cerevisiae YE4. Food Res Int 2023; 166:112612. [PMID: 36914328 DOI: 10.1016/j.foodres.2023.112612] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 02/11/2023] [Accepted: 02/14/2023] [Indexed: 02/25/2023]
Abstract
The interaction mode between lactic acid bacteria (LAB) and yeast in a fermentation system directly determines the quality of the products, thus understanding their mode of interaction can improve product quality. The present study investigated the effects of Saccharomyces cerevisiae YE4 on LAB from the perspectives of physiology, quorum sensing (QS), and proteomics. The presence of S. cerevisiae YE4 slowed down the growth of Enterococcus faecium 8-3 but had no significant effect on acid production or biofilm formation. S. cerevisiae YE4 significantly reduced the activity of autoinducer-2 at 19 h in E. faecium 8-3 and at 7-13 h in Lactobacillus fermentum 2-1. Expression of the QS-related genes luxS and pfs was also inhibited at 7 h. Moreover, a total of 107 E. faecium 8-3 proteins differed significantly in coculture with S. cerevisiae YE4-these proteins are involved in metabolic pathways including biosynthesis of secondary metabolites; biosynthesis of amino acids; alanine, aspartate, and glutamate metabolism; fatty acid metabolism; and fatty acid biosynthesis. Among them, proteins involved in cell adhesion, cell wall formation, two-component systems, and ABC transporters were detected. Therefore, S. cerevisiae YE4 might affect the physiological metabolism of E. faecium 8-3 by affecting cell adhesion, cell wall formation, and cell-cell interactions.
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Affiliation(s)
- Yue Gu
- College of Food Science and Engineering, Inner Mongolia Agricultural University, 306 Zhaowuda Road, Hohhot, Inner Mongolia 010018, China
| | - Baojun Zhang
- College of Food Science and Engineering, Inner Mongolia Agricultural University, 306 Zhaowuda Road, Hohhot, Inner Mongolia 010018, China
| | - Jianjun Tian
- College of Food Science and Engineering, Inner Mongolia Agricultural University, 306 Zhaowuda Road, Hohhot, Inner Mongolia 010018, China
| | - Lijie Li
- College of Food Science and Engineering, Inner Mongolia Agricultural University, 306 Zhaowuda Road, Hohhot, Inner Mongolia 010018, China.
| | - Yinfeng He
- College of Food Science and Engineering, Inner Mongolia Agricultural University, 306 Zhaowuda Road, Hohhot, Inner Mongolia 010018, China.
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Ghio C, Soukup JM, Dailey LA, Ghio AJ, Schreinemachers DM, Koppes RA, Koppes AN. Lactate Production can Function to Increase Human Epithelial Cell Iron Concentration. Cell Mol Bioeng 2022; 15:571-585. [PMID: 36531860 PMCID: PMC9751240 DOI: 10.1007/s12195-022-00741-z] [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: 03/26/2022] [Accepted: 09/21/2022] [Indexed: 11/28/2022] Open
Abstract
Introduction Under conditions of limited iron availability, plants and microbes have evolved mechanisms to acquire iron. For example, metal deficiency stimulates reprogramming of carbon metabolism, increasing activity of enzymes involved in the Krebs cycle and the glycolytic pathway. Resultant carboxylates/hydroxycarboxylates then function as ligands to complex iron and facilitate solubilization and uptake, reversing the metal deficiency. Similarly, human intestinal epithelial cells may produce lactate, a hydroxycarboxylate, during absolute and functional iron deficiency to import metal to reverse limited availability. Methods Here we investigate (1) if lactate can increase cell metal import of epithelial cells in vitro, (2) if lactate dehydrogenase (LDH) activity in and lactate production by epithelial cells correspond to metal availability, and (3) if blood concentrations of LDH in a human cohort correlate with indices of iron homeostasis. Results Results show that exposures of human epithelial cells, Caco-2, to both sodium lactate and ferric ammonium citrate (FAC) increase metal import relative to FAC alone. Similarly, fumaric, isocitric, malic, and succinic acid coincubation with FAC increase iron import relative to FAC alone. Increased iron import following exposures to sodium lactate and FAC elevated both ferritin and metal associated with mitochondria. LDH did not change after exposure to deferoxamine but decreased with 24 h exposure to FAC. Lactate levels revealed decreased levels with FAC incubation. Review of the National Health and Nutrition Examination Survey demonstrated significant negative relationships between LDH concentrations and serum iron in human cohorts. Conclusions Therefore, we conclude that iron import in human epithelial cells can involve lactate, LDH activity can reflect the availability of this metal, and blood LDH concentrations can correlate with indices of iron homeostasis.
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Affiliation(s)
- Caroline Ghio
- Department of Chemical Engineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, MA 02115 USA
| | | | - Lisa A. Dailey
- US Environmental Protection Agency, Chapel Hill, NC 27514 USA
| | - Andrew J. Ghio
- US Environmental Protection Agency, Chapel Hill, NC 27514 USA
| | | | - Ryan A. Koppes
- Department of Chemical Engineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, MA 02115 USA
| | - Abigail N. Koppes
- Department of Chemical Engineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, MA 02115 USA
- Department of Biology, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, MA 02115 USA
- Department of Bioengineering, Northeastern University, 360 Huntington Ave., 313 Snell Engineering, Boston, MA 02115 USA
- Northeastern University, 360 Huntington Ave., 332 Mugar Life Science Building, Boston, MA 02115 USA
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7
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Ribeiro RA, Bourbon-Melo N, Sá-Correia I. The cell wall and the response and tolerance to stresses of biotechnological relevance in yeasts. Front Microbiol 2022; 13:953479. [PMID: 35966694 PMCID: PMC9366716 DOI: 10.3389/fmicb.2022.953479] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 07/11/2022] [Indexed: 01/18/2023] Open
Abstract
In industrial settings and processes, yeasts may face multiple adverse environmental conditions. These include exposure to non-optimal temperatures or pH, osmotic stress, and deleterious concentrations of diverse inhibitory compounds. These toxic chemicals may result from the desired accumulation of added-value bio-products, yeast metabolism, or be present or derive from the pre-treatment of feedstocks, as in lignocellulosic biomass hydrolysates. Adaptation and tolerance to industrially relevant stress factors involve highly complex and coordinated molecular mechanisms occurring in the yeast cell with repercussions on the performance and economy of bioprocesses, or on the microbiological stability and conservation of foods, beverages, and other goods. To sense, survive, and adapt to different stresses, yeasts rely on a network of signaling pathways to modulate the global transcriptional response and elicit coordinated changes in the cell. These pathways cooperate and tightly regulate the composition, organization and biophysical properties of the cell wall. The intricacy of the underlying regulatory networks reflects the major role of the cell wall as the first line of defense against a wide range of environmental stresses. However, the involvement of cell wall in the adaptation and tolerance of yeasts to multiple stresses of biotechnological relevance has not received the deserved attention. This article provides an overview of the molecular mechanisms involved in fine-tuning cell wall physicochemical properties during the stress response of Saccharomyces cerevisiae and their implication in stress tolerance. The available information for non-conventional yeast species is also included. These non-Saccharomyces species have recently been on the focus of very active research to better explore or control their biotechnological potential envisaging the transition to a sustainable circular bioeconomy.
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Affiliation(s)
- Ricardo A. Ribeiro
- Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
- Associate Laboratory i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Nuno Bourbon-Melo
- Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Isabel Sá-Correia
- Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
- Associate Laboratory i4HB—Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
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Li B, Liu N, Zhao X. Response mechanisms of Saccharomyces cerevisiae to the stress factors present in lignocellulose hydrolysate and strategies for constructing robust strains. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:28. [PMID: 35292082 PMCID: PMC8922928 DOI: 10.1186/s13068-022-02127-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 03/01/2022] [Indexed: 11/19/2022]
Abstract
Bioconversion of lignocellulosic biomass to biofuels such as bioethanol and high value-added products has attracted great interest in recent decades due to the carbon neutral nature of biomass feedstock. However, there are still many key technical difficulties for the industrial application of biomass bioconversion processes. One of the challenges associated with the microorganism Saccharomyces cerevisiae that is usually used for bioethanol production refers to the inhibition of the yeast by various stress factors. These inhibitive effects seriously restrict the growth and fermentation performance of the strains, resulting in reduced bioethanol production efficiency. Therefore, improving the stress response ability of the strains is of great significance for industrial production of bioethanol. In this article, the response mechanisms of S. cerevisiae to various hydrolysate-derived stress factors including organic acids, furan aldehydes, and phenolic compounds have been reviewed. Organic acids mainly stimulate cells to induce intracellular acidification, furan aldehydes mainly break the intracellular redox balance, and phenolic compounds have a greater effect on membrane homeostasis. These damages lead to inadequate intracellular energy supply and dysregulation of transcription and translation processes, and then activate a series of stress responses. The regulation mechanisms of S. cerevisiae in response to these stress factors are discussed with regard to the cell wall/membrane, energy, amino acids, transcriptional and translational, and redox regulation. The reported key target genes and transcription factors that contribute to the improvement of the strain performance are summarized. Furthermore, the genetic engineering strategies of constructing multilevel defense and eliminating stress effects are discussed in order to provide technical strategies for robust strain construction. It is recommended that robust S. cerevisiae can be constructed with the intervention of metabolic regulation based on the specific stress responses. Rational design with multilevel gene control and intensification of key enzymes can provide good strategies for construction of robust strains.
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Affiliation(s)
- Bo Li
- Key Laboratory of Industrial Biocatalysis, Ministry of Education, Tsinghua University, Beijing, 100084, China.,Institute of Applied Chemistry, Department of Chemical Engineering, Tsinghua University, Beijing, 100084, China
| | - Nan Liu
- Key Laboratory of Industrial Biocatalysis, Ministry of Education, Tsinghua University, Beijing, 100084, China.,Institute of Applied Chemistry, Department of Chemical Engineering, Tsinghua University, Beijing, 100084, China
| | - Xuebing Zhao
- Key Laboratory of Industrial Biocatalysis, Ministry of Education, Tsinghua University, Beijing, 100084, China. .,Institute of Applied Chemistry, Department of Chemical Engineering, Tsinghua University, Beijing, 100084, China.
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van Aalst AC, de Valk SC, van Gulik WM, Jansen ML, Pronk JT, Mans R. Pathway engineering strategies for improved product yield in yeast-based industrial ethanol production. Synth Syst Biotechnol 2022; 7:554-566. [PMID: 35128088 PMCID: PMC8792080 DOI: 10.1016/j.synbio.2021.12.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/22/2021] [Accepted: 12/23/2021] [Indexed: 12/16/2022] Open
Abstract
Product yield on carbohydrate feedstocks is a key performance indicator for industrial ethanol production with the yeast Saccharomyces cerevisiae. This paper reviews pathway engineering strategies for improving ethanol yield on glucose and/or sucrose in anaerobic cultures of this yeast by altering the ratio of ethanol production, yeast growth and glycerol formation. Particular attention is paid to strategies aimed at altering energy coupling of alcoholic fermentation and to strategies for altering redox-cofactor coupling in carbon and nitrogen metabolism that aim to reduce or eliminate the role of glycerol formation in anaerobic redox metabolism. In addition to providing an overview of scientific advances we discuss context dependency, theoretical impact and potential for industrial application of different proposed and developed strategies.
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Affiliation(s)
- Aafke C.A. van Aalst
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629, HZ Delft, the Netherlands
| | - Sophie C. de Valk
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629, HZ Delft, the Netherlands
| | - Walter M. van Gulik
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629, HZ Delft, the Netherlands
| | - Mickel L.A. Jansen
- DSM Biotechnology Centre, Alexander Fleminglaan 1, 2613, AX Delft, the Netherlands
| | - Jack T. Pronk
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629, HZ Delft, the Netherlands
| | - Robert Mans
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629, HZ Delft, the Netherlands
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10
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Continuous Production of Fumaric Acid with Immobilised Rhizopus oryzae: The Role of pH and Urea Addition. Catalysts 2022. [DOI: 10.3390/catal12010082] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Fumaric acid is widely used in the food and beverage, pharmaceutical and polyester resin industries. Rhizopus oryzae is the most successful microorganism at excreting fumaric acid compared to all known natural and genetically modified organisms. It has previously been discovered that careful control of the glucose feed rate can eliminate the by-product formation of ethanol. Two key parameters affecting fumaric acid excretion were identified, namely the medium pH and the urea feed rate. A continuous fermentation with immobilised R. oryzae was utilised to determine the effect of these parameters. It was found that the selectivity for fumaric acid production increased at high glucose consumption rates for a pH of 4, different from the trend for pH 5 and 6, achieving a yield of 0.93 gg−1. This yield is higher than previously reported in the literature. Varying the urea feed rate to 0.255 mgL−1h−1 improved the yield of fumaric acid but experienced a lower glucose uptake rate compared to higher urea feed rates. An optimum region has been found for fumaric acid production at pH 4, a urea feed rate of 0.625 mgL−1h−1 and a glucose feed rate of 0.329 gL−1h−1.
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Coradini ALV, da Silveira Bezerra de Mello F, Furlan M, Maneira C, Carazzolle MF, Pereira GAG, Teixeira GS. QTL mapping of a Brazilian bioethanol strain links the cell wall protein-encoding gene GAS1 to low pH tolerance in S. cerevisiae. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:239. [PMID: 34915919 PMCID: PMC8675505 DOI: 10.1186/s13068-021-02079-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 11/17/2021] [Indexed: 06/14/2023]
Abstract
BACKGROUND Saccharomyces cerevisiae is largely applied in many biotechnological processes, from traditional food and beverage industries to modern biofuel and biochemicals factories. During the fermentation process, yeast cells are usually challenged in different harsh conditions, which often impact productivity. Regarding bioethanol production, cell exposure to acidic environments is related to productivity loss on both first- and second-generation ethanol. In this scenario, indigenous strains traditionally used in fermentation stand out as a source of complex genetic architecture, mainly due to their highly robust background-including low pH tolerance. RESULTS In this work, we pioneer the use of QTL mapping to uncover the genetic basis that confers to the industrial strain Pedra-2 (PE-2) acidic tolerance during growth at low pH. First, we developed a fluorescence-based high-throughput approach to collect a large number of haploid cells using flow cytometry. Then, we were able to apply a bulk segregant analysis to solve the genetic basis of low pH resistance in PE-2, which uncovered a region in chromosome X as the major QTL associated with the evaluated phenotype. A reciprocal hemizygosity analysis revealed the allele GAS1, encoding a β-1,3-glucanosyltransferase, as the casual variant in this region. The GAS1 sequence alignment of distinct S. cerevisiae strains pointed out a non-synonymous mutation (A631G) prevalence in wild-type isolates, which is absent in laboratory strains. We further showcase that GAS1 allele swap between PE-2 and a low pH-susceptible strain can improve cell viability on the latter of up to 12% after a sulfuric acid wash process. CONCLUSION This work revealed GAS1 as one of the main causative genes associated with tolerance to growth at low pH in PE-2. We also showcase how GAS1PE-2 can improve acid resistance of a susceptible strain, suggesting that these findings can be a powerful foundation for the development of more robust and acid-tolerant strains. Our results collectively show the importance of tailored industrial isolated strains in discovering the genetic architecture of relevant traits and its implications over productivity.
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Affiliation(s)
- Alessandro L V Coradini
- Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, University of Campinas, Rua Monteiro Lobato 255, Campinas, 13083-862, Brazil
- Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, 90089-2910, USA
| | - Fellipe da Silveira Bezerra de Mello
- Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, University of Campinas, Rua Monteiro Lobato 255, Campinas, 13083-862, Brazil
| | - Monique Furlan
- Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, University of Campinas, Rua Monteiro Lobato 255, Campinas, 13083-862, Brazil
| | - Carla Maneira
- Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, University of Campinas, Rua Monteiro Lobato 255, Campinas, 13083-862, Brazil
| | - Marcelo F Carazzolle
- Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, University of Campinas, Rua Monteiro Lobato 255, Campinas, 13083-862, Brazil
| | - Gonçalo Amarante Guimaraes Pereira
- Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, University of Campinas, Rua Monteiro Lobato 255, Campinas, 13083-862, Brazil.
| | - Gleidson Silva Teixeira
- Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, University of Campinas, Rua Monteiro Lobato 255, Campinas, 13083-862, Brazil
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12
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Jang BK, Ju Y, Jeong D, Jung SK, Kim CK, Chung YS, Kim SR. l-Lactic Acid Production Using Engineered Saccharomyces cerevisiae with Improved Organic Acid Tolerance. J Fungi (Basel) 2021; 7:jof7110928. [PMID: 34829217 PMCID: PMC8624227 DOI: 10.3390/jof7110928] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/29/2021] [Accepted: 10/30/2021] [Indexed: 11/16/2022] Open
Abstract
Lactic acid is mainly used to produce bio-based, bio-degradable polylactic acid. For industrial production of lactic acid, engineered Saccharomyces cerevisiae can be used. To avoid cellular toxicity caused by lactic acid accumulation, pH-neutralizing agents are used, leading to increased production costs. In this study, lactic acid-producing S. cerevisiae BK01 was developed with improved lactic acid tolerance through adaptive laboratory evolution (ALE) on 8% lactic acid. The genetic basis of BK01 could not be determined, suggesting complex mechanisms associated with lactic acid tolerance. However, BK01 had distinctive metabolomic traits clearly separated from the parental strain, and lactic acid production was improved by 17% (from 102 g/L to 119 g/L). To the best of our knowledge, this is the highest lactic acid titer produced by engineered S. cerevisiae without the use of pH neutralizers. Moreover, cellulosic lactic acid production by BK01 was demonstrated using acetate-rich buckwheat husk hydrolysates. Particularly, BK01 revealed improved tolerance against acetic acid of the hydrolysates, a major fermentation inhibitor of lignocellulosic biomass. In short, ALE with a high concentration of lactic acid improved lactic acid production as well as acetic acid tolerance of BK01, suggesting a potential for economically viable cellulosic lactic acid production.
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Affiliation(s)
- Byeong-Kwan Jang
- Major in Food Application Technology, School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Korea; (B.-K.J.); (Y.J.); (D.J.); (S.-K.J.)
| | - Yebin Ju
- Major in Food Application Technology, School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Korea; (B.-K.J.); (Y.J.); (D.J.); (S.-K.J.)
| | - Deokyeol Jeong
- Major in Food Application Technology, School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Korea; (B.-K.J.); (Y.J.); (D.J.); (S.-K.J.)
| | - Sung-Keun Jung
- Major in Food Application Technology, School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Korea; (B.-K.J.); (Y.J.); (D.J.); (S.-K.J.)
| | - Chang-Kil Kim
- Department of Horticulture, Kyungpook National University, Daegu 41566, Korea;
| | - Yong-Suk Chung
- Department of Plant Resources and Environment, Jeju National University, Jeju 63243, Korea
- Correspondence: (Y.-S.C.); (S.-R.K.)
| | - Soo-Rin Kim
- Major in Food Application Technology, School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Korea; (B.-K.J.); (Y.J.); (D.J.); (S.-K.J.)
- Correspondence: (Y.-S.C.); (S.-R.K.)
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13
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Solieri L. The revenge of Zygosaccharomyces yeasts in food biotechnology and applied microbiology. World J Microbiol Biotechnol 2021; 37:96. [PMID: 33969449 DOI: 10.1007/s11274-021-03066-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 04/28/2021] [Indexed: 12/01/2022]
Abstract
Non-conventional yeasts refer to a huge and still poorly explored group of species alternative to the well-known model organism Saccharomyces cerevisiae. Among them, Zygosaccharomyces rouxii and the sister species Zygosaccharomyces bailii are infamous for spoiling food and beverages even in presence of several food preservatives. On the other hand, their capability to cope with a wide range of process conditions makes these yeasts very attractive factories (the so-called "ZygoFactories") for bio-converting substrates poorly permissive for the growth of other species. In balsamic vinegar Z. rouxii is the main yeast responsible for converting highly concentrated sugars into ethanol, with a preference for fructose over glucose (a trait called fructophily). Z. rouxii has also attracted much attention for the ability to release important flavor compounds, such as fusel alcohols and the derivatives of 4-hydroxyfuranone, which markedly contribute to fragrant and smoky aroma in soy sauce. While Z. rouxii was successfully proposed in brewing for producing low ethanol beer, Z. bailii is promising for lactic acid and bioethanol production. Recently, several research efforts exploited omics tools to pinpoint the genetic bases of distinctive traits in "ZygoFactories", like fructophily, tolerance to high concentrations of sugars, lactic acid and salt. Here, I provided an overview of Zygosaccharomyces industrially relevant phenotypes and summarized the most recent findings in disclosing their genetic bases. I suggest that the increasing number of genomes available for Z. rouxii and other Zygosaccharomyces relatives, combined with recently developed genetic engineering toolkits, will boost the applications of these yeasts in biotechnology and applied microbiology.
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Affiliation(s)
- L Solieri
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122, Reggio Emilia, Italy.
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14
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Peetermans A, Foulquié-Moreno MR, Thevelein JM. Mechanisms underlying lactic acid tolerance and its influence on lactic acid production in Saccharomyces cerevisiae. MICROBIAL CELL 2021; 8:111-130. [PMID: 34055965 PMCID: PMC8144909 DOI: 10.15698/mic2021.06.751] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
One of the major bottlenecks in lactic acid production using microbial fermentation is the detrimental influence lactic acid accumulation poses on the lactic acid producing cells. The accumulation of lactic acid results in many negative effects on the cell such as intracellular acidification, anion accumulation, membrane perturbation, disturbed amino acid trafficking, increased turgor pressure, ATP depletion, ROS accumulation, metabolic dysregulation and metal chelation. In this review, the manner in which Saccharomyces cerevisiae deals with these issues will be discussed extensively not only for lactic acid as a singular stress factor but also in combination with other stresses. In addition, different methods to improve lactic acid tolerance in S. cerevisiae using targeted and non-targeted engineering methods will be discussed.
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Affiliation(s)
- Arne Peetermans
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Flanders, Belgium.,Center for Microbiology, VIB, Kasteelpark Arenberg 31, B-3001, Leuven-Heverlee, Flanders, Belgium
| | - María R Foulquié-Moreno
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Flanders, Belgium.,Center for Microbiology, VIB, Kasteelpark Arenberg 31, B-3001, Leuven-Heverlee, Flanders, Belgium
| | - Johan M Thevelein
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Flanders, Belgium.,Center for Microbiology, VIB, Kasteelpark Arenberg 31, B-3001, Leuven-Heverlee, Flanders, Belgium.,NovelYeast bv, Open Bio-Incubator, Erasmus High School, Laarbeeklaan 121, 1090 Brussels (Jette), Belgium
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15
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Fletcher E, Mercurio K, Walden EA, Baetz K. A yeast chemogenomic screen identifies pathways that modulate adipic acid toxicity. iScience 2021; 24:102327. [PMID: 33889823 PMCID: PMC8050732 DOI: 10.1016/j.isci.2021.102327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/19/2021] [Accepted: 03/15/2021] [Indexed: 11/18/2022] Open
Abstract
Adipic acid production by yeast fermentation is gaining attention as a renewable source of platform chemicals for making nylon products. However, adipic acid toxicity inhibits yeast growth and fermentation. Here, we performed a chemogenomic screen in Saccharomyces cerevisiae to understand the cellular basis of adipic acid toxicity. Our screen revealed that KGD1 (a key gene in the tricarboxylic acid cycle) deletion improved tolerance to adipic acid and its toxic precursor, catechol. Conversely, disrupting ergosterol biosynthesis as well as protein trafficking and vacuolar transport resulted in adipic acid hypersensitivity. Notably, we show that adipic acid disrupts the Membrane Compartment of Can1 (MCC) on the plasma membrane and impacts endocytosis. This was evidenced by the rapid internalization of Can1 for vacuolar degradation. As ergosterol is an essential component of the MCC and protein trafficking mechanisms are required for endocytosis, we highlight the importance of these cellular processes in modulating adipic acid toxicity. Deletion of the TCA cycle gene KGD1 improves tolerance to adipic acid and catechol Ergosterol and Pdr12 play non-overlapping roles protecting cell from adipic acid Adipic acid-induced plasma membrane localization of Pdr12 is independent of ergosterol Adipic acid disrupts the Membrane Compartment of Can1 (MCC) and induces endocytosis
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Affiliation(s)
- Eugene Fletcher
- Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, 451 Smyth Road, Ottawa, ON K1H 8M5, Canada
| | - Kevin Mercurio
- Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, 451 Smyth Road, Ottawa, ON K1H 8M5, Canada
| | - Elizabeth A. Walden
- Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, 451 Smyth Road, Ottawa, ON K1H 8M5, Canada
| | - Kristin Baetz
- Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, 451 Smyth Road, Ottawa, ON K1H 8M5, Canada
- Corresponding author
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16
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Senne de Oliveira Lino F, Bajic D, Vila JCC, Sánchez A, Sommer MOA. Complex yeast-bacteria interactions affect the yield of industrial ethanol fermentation. Nat Commun 2021; 12:1498. [PMID: 33686084 PMCID: PMC7940389 DOI: 10.1038/s41467-021-21844-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 02/10/2021] [Indexed: 01/31/2023] Open
Abstract
Sugarcane ethanol fermentation represents a simple microbial community dominated by S. cerevisiae and co-occurring bacteria with a clearly defined functionality. In this study, we dissect the microbial interactions in sugarcane ethanol fermentation by combinatorically reconstituting every possible combination of species, comprising approximately 80% of the biodiversity in terms of relative abundance. Functional landscape analysis shows that higher-order interactions counterbalance the negative effect of pairwise interactions on ethanol yield. In addition, we find that Lactobacillus amylovorus improves the yeast growth rate and ethanol yield by cross-feeding acetaldehyde, as shown by flux balance analysis and laboratory experiments. Our results suggest that Lactobacillus amylovorus could be considered a beneficial bacterium with the potential to improve sugarcane ethanol fermentation yields by almost 3%. These data highlight the biotechnological importance of comprehensively studying microbial communities and could be extended to other microbial systems with relevance to human health and the environment.
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Affiliation(s)
| | - Djordje Bajic
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
| | - Jean Celestin Charles Vila
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
| | - Alvaro Sánchez
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
| | - Morten Otto Alexander Sommer
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark.
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17
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Effects of Lactobacillus plantarum on the ethanol tolerance of Saccharomyces cerevisiae. Appl Microbiol Biotechnol 2021; 105:2597-2611. [PMID: 33646374 DOI: 10.1007/s00253-021-11198-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 02/05/2021] [Accepted: 02/24/2021] [Indexed: 10/22/2022]
Abstract
The bioethanol fermentation by Saccharomyces cerevisiae is often challenged by bacterial contamination, especially lactic acid bacteria (LAB). LAB can inhibit the growth S. cerevisiae by secreting organic acids and competing for nutrients and physical space. However, the range of favorable effects attributed to LAB during bioethanol fermentation, and their associated mechanisms of regulation, are not fully understood. This study was performed to clarify the effects of Lactobacillus plantarum, an important contaminative LAB in bioethanol fermentation, on the mechanism of ethanol tolerance in S. cerevisiae. The results showed that the presence of L. plantarum increased the ethanol tolerance of S. cerevisiae by promoting or inhibiting various metabolic processes in the yeast cells: The metabolism of trehalose, ergosterol, certain amino acids, proton pumps, stress response transcriptional activators, and heat shock proteins were all promoted; amounts of intracellular monounsaturated fatty acids and the accumulation of reactive oxygen species were inhibited. Furthermore, the maintenance of the acquired higher ethanol tolerance of S. cerevisiae was dependent on the coexistence of L. plantarum. These results suggested a complex relationship existed between S. cerevisiae and the contaminating LAB that might also play a beneficial role during fermentation by promoting the ethanol tolerance of yeast. The results from this study suggested that the extent of controlling bacterial contamination on bioethanol fermentation efficiency should be given careful consideration. KEY POINTS: • L. plantarum improved the ethanol tolerance of S. cerevisiae. • L. plantarum regulated the ethanol tolerance-related metabolism of yeast cells. • L. plantarum coexistence facilitated maintenance of ethanol tolerance in yeast cells.
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18
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Gubelt A, Blaschke L, Hahn T, Rupp S, Hirth T, Zibek S. Comparison of Different Lactobacilli Regarding Substrate Utilization and Their Tolerance Towards Lignocellulose Degradation Products. Curr Microbiol 2020; 77:3136-3146. [PMID: 32728792 PMCID: PMC7452873 DOI: 10.1007/s00284-020-02131-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 07/14/2020] [Indexed: 11/29/2022]
Abstract
Fermentative lactic acid production is currently impeded by low pH tolerance of the production organisms, the successive substrate consumption of the strains and/or the requirement to apply purified substrate streams. We identified Lactobacillus brevis IGB 1.29 in compost, which is capable of producing lactic acid at low pH values from lignocellulose hydrolysates, simultaneously consuming glucose and xylose. In this study, we compared Lactobacillus brevis IGB 1.29 with the reference strains Lactobacillus brevis ATCC 367, Lactobacillus plantarum NCIMB 8826 and Lactococcus lactis JCM 7638 with regard to the consumption of C5- and C6-sugars. Simultaneous conversion of C5- and C6-monosaccharides was confirmed for L. brevis IGB 1.29 with consumption rates of 1.6 g/(L h) for glucose and 1.0 g/(L h) for xylose. Consumption rates were lower for L. brevis ATCC 367 with 0.6 g/(L h) for glucose and 0.2 g/(L h) for xylose. Further trials were carried out to determine the sensitivity towards common toxic degradation products in lignocellulose hydrolysates: acetate, hydroxymethylfurfural, furfural, formate, levulinic acid and phenolic compounds from hemicellulose fraction. L. lactis was the least tolerant strain towards the inhibitors, whereas L. brevis IGB 1.29 showed the highest tolerance. L. brevis IGB 1.29 exhibited only 10% growth reduction at concentrations of 26.0 g/L acetate, 1.2 g/L furfural, 5.0 g/L formate, 6.6 g/L hydroxymethylfurfural, 9.2 g/L levulinic acid or 2.2 g/L phenolic compounds. This study describes a new strain L. brevis IGB 1.29, that enables efficient lactic acid production with a lignocellulose-derived C5- and C6-sugar fraction.
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Affiliation(s)
- Angela Gubelt
- Institute of Interfacial Process Engineering and Plasma Technology, University Stuttgart, Nobelstraße 12, 70569, Stuttgart, Germany.,Institute for Bio- and Geosciences: Plant Sciences, Forschungszentrum Jülich, Jülich, Germany
| | - Lisa Blaschke
- Institute of Interfacial Process Engineering and Plasma Technology, University Stuttgart, Nobelstraße 12, 70569, Stuttgart, Germany.,Sartorius Stedim Cellca GmbH, Ulm, Germany
| | - Thomas Hahn
- Industrial Biotechnology, Fraunhofer Institute of Interfacial and Bioprocess Engineering, Stuttgart, Germany
| | - Steffen Rupp
- Institute of Interfacial Process Engineering and Plasma Technology, University Stuttgart, Nobelstraße 12, 70569, Stuttgart, Germany.,Industrial Biotechnology, Fraunhofer Institute of Interfacial and Bioprocess Engineering, Stuttgart, Germany
| | - Thomas Hirth
- Institute of Interfacial Process Engineering and Plasma Technology, University Stuttgart, Nobelstraße 12, 70569, Stuttgart, Germany.,Industrial Biotechnology, Fraunhofer Institute of Interfacial and Bioprocess Engineering, Stuttgart, Germany.,Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Susanne Zibek
- Institute of Interfacial Process Engineering and Plasma Technology, University Stuttgart, Nobelstraße 12, 70569, Stuttgart, Germany. .,Industrial Biotechnology, Fraunhofer Institute of Interfacial and Bioprocess Engineering, Stuttgart, Germany.
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19
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Deng N, Du H, Xu Y. Cooperative Response of Pichia kudriavzevii and Saccharomyces cerevisiae to Lactic Acid Stress in Baijiu Fermentation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:4903-4911. [PMID: 32180399 DOI: 10.1021/acs.jafc.9b08052] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Lactic acid is a universal metabolite, as well as a growth inhibitor of ethanol producers in Baijiu fermentation. Revealing the mechanism of lactic acid tolerance is essential for the yield of fermented foods. Here, we employed reverse transcription-quantitative polymerase chain reaction to explore the degradation mechanism of lactic acid, based on the coculture of Pichia kudriavzevii and Saccharomyces cerevisiae. Under high lactic acid stress, P. kudriavzevii decreased lactic acid from 40.00 to 35.46 g L-1 within 24 h. Then, S. cerevisiae restored its capacity to degrade lactic acid. Finally, lactic acid decreased to 26.29 g L-1. Coculture significantly enhanced lactic acid consumption compared to the monoculture of P. kudriavzevii (90% higher) or S. cerevisiae (209% higher). We found that lactate catabolism, H+ extrusion, and glycerol transport were the lactic acid tolerance pathways in yeasts. This study reveals the novel acid tolerance mechanisms of microbiota and would provide new strategies for ethanol production under acid stress.
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Affiliation(s)
- Nan Deng
- State Key Laboratory of Food Science and Technology, Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Hai Du
- State Key Laboratory of Food Science and Technology, Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China
- Institute for Chinese Jiang-Flavor Baijiu (Liquor), Renhuai, Guizhou 564500, China
| | - Yan Xu
- State Key Laboratory of Food Science and Technology, Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China
- Institute for Chinese Jiang-Flavor Baijiu (Liquor), Renhuai, Guizhou 564500, China
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20
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Totaro D, Rothbauer M, Steiger MG, Mayr T, Wang HY, Lin YS, Sauer M, Altvater M, Ertl P, Mattanovich D. Downscaling screening cultures in a multifunctional bioreactor array-on-a-chip for speeding up optimization of yeast-based lactic acid bioproduction. Biotechnol Bioeng 2020; 117:2046-2057. [PMID: 32190900 PMCID: PMC7317386 DOI: 10.1002/bit.27338] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/21/2020] [Accepted: 03/17/2020] [Indexed: 01/09/2023]
Abstract
A key challenge for bioprocess engineering is the identification of the optimum process conditions for the production of biochemical and biopharmaceutical compounds using prokaryotic as well as eukaryotic cell factories. Shake flasks and bench-scale bioreactor systems are still the golden standard in the early stage of bioprocess development, though they are known to be expensive, time-consuming, and labor-intensive as well as lacking the throughput for efficient production optimizations. To bridge the technological gap between bioprocess optimization and upscaling, we have developed a microfluidic bioreactor array to reduce time and costs, and to increase throughput compared with traditional lab-scale culture strategies. We present a multifunctional microfluidic device containing 12 individual bioreactors (Vt = 15 µl) in a 26 mm × 76 mm area with in-line biosensing of dissolved oxygen and biomass concentration. Following initial device characterization, the bioreactor lab-on-a-chip was used in a proof-of-principle study to identify the most productive cell line for lactic acid production out of two engineered yeast strains, evaluating whether it could reduce the time needed for collecting meaningful data compared with shake flasks cultures. Results of the study showed significant difference in the strains' productivity within 3 hr of operation exhibiting a 4- to 6-fold higher lactic acid production, thus pointing at the potential of microfluidic technology as effective screening tool for fast and parallelizable industrial bioprocess development.
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Affiliation(s)
- Damiano Totaro
- ACIB GmbH, Austrian Centre of Industrial Biotechnology, Vienna, Austria.,Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Faculty of Technical Chemistry, Vienna University of Technology, Vienna, Austria
| | - Mario Rothbauer
- Faculty of Technical Chemistry, Vienna University of Technology, Vienna, Austria
| | - Matthias G Steiger
- ACIB GmbH, Austrian Centre of Industrial Biotechnology, Vienna, Austria.,Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Institute of Chemical, Environmental and Bioscience Engineering, Vienna University of Technology, Vienna, Austria
| | - Torsten Mayr
- Institute of Analytical Chemistry and Food Chemistry, Graz University of Technology, Graz, Austria
| | - Hsiang-Yu Wang
- Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Yu-Sheng Lin
- Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Michael Sauer
- ACIB GmbH, Austrian Centre of Industrial Biotechnology, Vienna, Austria.,Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Martin Altvater
- ACIB GmbH, Austrian Centre of Industrial Biotechnology, Vienna, Austria.,Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Peter Ertl
- Faculty of Technical Chemistry, Vienna University of Technology, Vienna, Austria
| | - Diethard Mattanovich
- ACIB GmbH, Austrian Centre of Industrial Biotechnology, Vienna, Austria.,Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
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21
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Hakkaart X, Liu Y, Hulst M, El Masoudi A, Peuscher E, Pronk J, van Gulik W, Daran-Lapujade P. Physiological responses of Saccharomyces cerevisiae to industrially relevant conditions: Slow growth, low pH, and high CO 2 levels. Biotechnol Bioeng 2020; 117:721-735. [PMID: 31654410 PMCID: PMC7028085 DOI: 10.1002/bit.27210] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 10/12/2019] [Accepted: 10/22/2019] [Indexed: 12/21/2022]
Abstract
Engineered strains of Saccharomyces cerevisiae are used for industrial production of succinic acid. Optimal process conditions for dicarboxylic‐acid yield and recovery include slow growth, low pH, and high CO2. To quantify and understand how these process parameters affect yeast physiology, this study investigates individual and combined impacts of low pH (3.0) and high CO2 (50%) on slow‐growing chemostat and retentostat cultures of the reference strain S. cerevisiae CEN.PK113‐7D. Combined exposure to low pH and high CO2 led to increased maintenance‐energy requirements and death rates in aerobic, glucose‐limited cultures. Further experiments showed that these effects were predominantly caused by low pH. Growth under ammonium‐limited, energy‐excess conditions did not aggravate or ameliorate these adverse impacts. Despite the absence of a synergistic effect of low pH and high CO2 on physiology, high CO2 strongly affected genome‐wide transcriptional responses to low pH. Interference of high CO2 with low‐pH signaling is consistent with low‐pH and high‐CO2 signals being relayed via common (MAPK) signaling pathways, notably the cell wall integrity, high‐osmolarity glycerol, and calcineurin pathways. This study highlights the need to further increase robustness of cell factories to low pH for carboxylic‐acid production, even in organisms that are already applied at industrial scale.
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Affiliation(s)
- Xavier Hakkaart
- Department of Biotechnology, Delft University of Technology, van der Maasweg, Delft, The Netherlands
| | - Yaya Liu
- Department of Biotechnology, Delft University of Technology, van der Maasweg, Delft, The Netherlands
| | - Mandy Hulst
- Department of Biotechnology, Delft University of Technology, van der Maasweg, Delft, The Netherlands
| | - Anissa El Masoudi
- Department of Biotechnology, Delft University of Technology, van der Maasweg, Delft, The Netherlands
| | - Eveline Peuscher
- Department of Biotechnology, Delft University of Technology, van der Maasweg, Delft, The Netherlands
| | - Jack Pronk
- Department of Biotechnology, Delft University of Technology, van der Maasweg, Delft, The Netherlands
| | - Walter van Gulik
- Department of Biotechnology, Delft University of Technology, van der Maasweg, Delft, The Netherlands
| | - Pascale Daran-Lapujade
- Department of Biotechnology, Delft University of Technology, van der Maasweg, Delft, The Netherlands
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22
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Valk LC, Luttik MAH, de Ram C, Pabst M, van den Broek M, van Loosdrecht MCM, Pronk JT. A Novel D-Galacturonate Fermentation Pathway in Lactobacillus suebicus Links Initial Reactions of the Galacturonate-Isomerase Route With the Phosphoketolase Pathway. Front Microbiol 2020; 10:3027. [PMID: 32010092 PMCID: PMC6978723 DOI: 10.3389/fmicb.2019.03027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 12/17/2019] [Indexed: 11/13/2022] Open
Abstract
D-galacturonate, a key constituent of pectin, is a ubiquitous monomer in plant biomass. Anaerobic, fermentative conversion of D-galacturonate is therefore relevant in natural environments as well as in microbial processes for microbial conversion of pectin-containing agricultural residues. In currently known microorganisms that anaerobically ferment D-galacturonate, its catabolism occurs via the galacturonate-isomerase pathway. Redox-cofactor balancing in this pathway strongly constrains the possible range of products generated from anaerobic D-galacturonate fermentation, resulting in acetate as the predominant organic fermentation product. To explore metabolic diversity of microbial D-galacturonate fermentation, anaerobic enrichment cultures were performed at pH 4. Anaerobic batch and chemostat cultures of a dominant Lactobacillus suebicus strain isolated from these enrichment cultures produced near-equimolar amounts of lactate and acetate from D-galacturonate. A combination of whole-genome sequence analysis, quantitative proteomics, enzyme activity assays in cell extracts, and in vitro product identification demonstrated that D-galacturonate metabolism in L. suebicus occurs via a novel pathway. In this pathway, mannonate generated by the initial reactions of the canonical isomerase pathway is converted to 6-phosphogluconate by two novel biochemical reactions, catalyzed by a mannonate kinase and a 6-phosphomannonate 2-epimerase. Further catabolism of 6-phosphogluconate then proceeds via known reactions of the phosphoketolase pathway. In contrast to the classical isomerase pathway for D-galacturonate catabolism, the novel pathway enables redox-cofactor-neutral conversion of D-galacturonate to ribulose-5-phosphate. While further research is required to identify the structural genes encoding the key enzymes for the novel pathway, its redox-cofactor coupling is highly interesting for metabolic engineering of microbial cell factories for conversion of pectin-containing feedstocks into added-value fermentation products such as ethanol or lactate. This study illustrates the potential of microbial enrichment cultivation to identify novel pathways for the conversion of environmentally and industrially relevant compounds.
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Affiliation(s)
| | | | | | | | | | | | - Jack T. Pronk
- Department of Biotechnology, Delft University of Technology, Delft, Netherlands
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Gao R, Li Z, Zhou X, Bao W, Cheng S, Zheng L. Enhanced lipid production by Yarrowia lipolytica cultured with synthetic and waste-derived high-content volatile fatty acids under alkaline conditions. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:3. [PMID: 31911818 PMCID: PMC6945533 DOI: 10.1186/s13068-019-1645-y] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 12/27/2019] [Indexed: 05/02/2023]
Abstract
BACKGROUND Volatile fatty acids (VFAs) can be effective and promising alternate carbon sources for microbial lipid production by a few oleaginous yeasts. However, the severe inhibitory effect of high-content (> 10 g/L) VFAs on these yeasts has impeded the production of high lipid yields and their large-scale application. Slightly acidic conditions have been commonly adopted because they have been considered favorable to oleaginous yeast cultivation. However, the acidic pH environment further aggravates this inhibition because VFAs appear largely in an undissociated form under this condition. Alkaline conditions likely alleviate the severe inhibition of high-content VFAs by significantly increasing the dissociation degree of VFAs. This hypothesis should be verified through a systematic research. RESULTS The combined effects of high acetic acid concentrations and alkaline conditions on VFA utilization, cell growth, and lipid accumulation of Yarrowia lipolytica were systematically investigated through batch cultures of Y. lipolytica by using high concentrations (30-110 g/L) of acetic acid as a carbon source at an initial pH ranging from 6 to 10. An initial pH of 8 was determined as optimal. The highest biomass and lipid production (37.14 and 10.11 g/L) were obtained with 70 g/L acetic acid, whereas cultures with > 70 g/L acetic acid had decreased biomass and lipid yield due to excessive anion accumulation. Feasibilities on high-content propionic acid, butyric acid, and mixed VFAs were compared and evaluated. Results indicated that Y X/S and Y L/S of cultures on butyric acid (0.570, 0.144) were comparable with those on acetic acid (0.578, 0.160) under alkaline conditions. The performance on propionic acid was much inferior to that on other acids. Mixed VFAs were more beneficial to fast adaptation and lipid production than single types of VFA. Furthermore, cultures on food waste (FW) and fruit and vegetable waste (FVW) fermentate were carried out and lipid production was effectively improved under this alkaline condition. The highest biomass and lipid production on FW fermentate reached 14.65 g/L (Y X/S: 0.414) and 3.20 g/L (Y L/S: 0.091) with a lipid content of 21.86%, respectively. By comparison, the highest biomass and lipid production on FVW fermentate were 11.84 g/L (Y X/S: 0.534) and 3.08 g/L (Y L/S: 0.139), respectively, with a lipid content of 26.02%. CONCLUSIONS This study assumed and verified that alkaline conditions (optimal pH 8) could effectively alleviate the lethal effect of high-content VFA on Y. lipolytica and significantly improve biomass and lipid production. These results could provide a new cultivation strategy to achieve simple utilizations of high-content VFAs and increase lipid production. Feasibilities on FW and FVW-derived VFAs were evaluated, and meaningful information was provided for practical applications.
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Affiliation(s)
- Ruiling Gao
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083 People’s Republic of China
| | - Zifu Li
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083 People’s Republic of China
| | - Xiaoqin Zhou
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083 People’s Republic of China
| | - Wenjun Bao
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083 People’s Republic of China
| | - Shikun Cheng
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083 People’s Republic of China
| | - Lei Zheng
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083 People’s Republic of China
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24
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Kang K, Bergdahl B, Machado D, Dato L, Han TL, Li J, Villas-Boas S, Herrgård MJ, Förster J, Panagiotou G. Linking genetic, metabolic, and phenotypic diversity among Saccharomyces cerevisiae strains using multi-omics associations. Gigascience 2019; 8:giz015. [PMID: 30715293 PMCID: PMC6446221 DOI: 10.1093/gigascience/giz015] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 12/29/2018] [Accepted: 01/24/2019] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The selection of bioengineering platform strains and engineering strategies to improve the stress resistance of Saccharomyces cerevisiae remains a pressing need in bio-based chemical production. Thus, a systematic effort to exploit genotypic and phenotypic diversity to boost yeast's industrial value is still urgently needed. RESULTS We analyzed 5,400 growth curves obtained from 36 S. cerevisiae strains and comprehensively profiled their resistances against 13 industrially relevant stresses. We observed that bioethanol and brewing strains exhibit higher resistance against acidic conditions; however, plant isolates tend to have a wider range of resistance, which may be associated with their metabolome and fluxome signatures in the tricarboxylic acid cycle and fatty acid metabolism. By deep genomic sequencing, we found that industrial strains have more genomic duplications especially affecting transcription factors, showing that they result from disparate evolutionary paths in comparison with the environmental strains, which have more indels, gene deletions, and strain-specific genes. Genome-wide association studies coupled with protein-protein interaction networks uncovered novel genetic determinants of stress resistances. CONCLUSIONS These resistance-related engineering targets and strain rankings provide a valuable source for engineering significantly improved industrial platform strains.
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Affiliation(s)
- Kang Kang
- Systems Biology & Bioinformatics Group, School of Biological Sciences, The University of Hong Kong, Hong Kong S.A.R., China
- Systems Biology & Bioinformatics Unit, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute, Jena, Germany
| | - Basti Bergdahl
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Daniel Machado
- Department of Biological Engineering, School of Engineering, University of Minho, Braga, Portugal
- The European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Laura Dato
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Ting-Li Han
- Centre for Microbial Innovation, School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Jun Li
- Systems Biology & Bioinformatics Group, School of Biological Sciences, The University of Hong Kong, Hong Kong S.A.R., China
- Systems Biology & Bioinformatics Unit, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute, Jena, Germany
| | - Silas Villas-Boas
- Centre for Microbial Innovation, School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Markus J Herrgård
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Jochen Förster
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Gianni Panagiotou
- Systems Biology & Bioinformatics Group, School of Biological Sciences, The University of Hong Kong, Hong Kong S.A.R., China
- Systems Biology & Bioinformatics Unit, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute, Jena, Germany
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
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Mans R, Hassing EJ, Wijsman M, Giezekamp A, Pronk JT, Daran JM, van Maris AJA. A CRISPR/Cas9-based exploration into the elusive mechanism for lactate export in Saccharomyces cerevisiae. FEMS Yeast Res 2019; 17:4628041. [PMID: 29145596 DOI: 10.1093/femsyr/fox085] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 11/13/2017] [Indexed: 11/14/2022] Open
Abstract
CRISPR/Cas9-based genome editing allows rapid, simultaneous modification of multiple genetic loci in Saccharomyces cerevisiae. Here, this technique was used in a functional analysis study aimed at identifying the hitherto unknown mechanism of lactate export in this yeast. First, an S. cerevisiae strain was constructed with deletions in 25 genes encoding transport proteins, including the complete aqua(glycero)porin family and all known carboxylic acid transporters. The 25-deletion strain was then transformed with an expression cassette for Lactobacillus casei lactate dehydrogenase (LcLDH). In anaerobic, glucose-grown batch cultures this strain exhibited a lower specific growth rate (0.15 vs. 0.25 h-1) and biomass-specific lactate production rate (0.7 vs. 2.4 mmol g biomass-1 h-1) than an LcLDH-expressing reference strain. However, a comparison of the two strains in anaerobic glucose-limited chemostat cultures (dilution rate 0.10 h-1) showed identical lactate production rates. These results indicate that, although deletion of the 25 transporter genes affected the maximum specific growth rate, it did not impact lactate export rates when analysed at a fixed specific growth rate. The 25-deletion strain provides a first step towards a 'minimal transportome' yeast platform, which can be applied for functional analysis of specific (heterologous) transport proteins as well as for evaluation of metabolic engineering strategies.
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Affiliation(s)
- Robert Mans
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Else-Jasmijn Hassing
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Melanie Wijsman
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Annabel Giezekamp
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Jack T Pronk
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Jean-Marc Daran
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Antonius J A van Maris
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
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Transcriptional Response to Lactic Acid Stress in the Hybrid Yeast Zygosaccharomyces parabailii. Appl Environ Microbiol 2018; 84:AEM.02294-17. [PMID: 29269498 PMCID: PMC5812937 DOI: 10.1128/aem.02294-17] [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: 10/17/2017] [Accepted: 12/12/2017] [Indexed: 12/29/2022] Open
Abstract
Lactic acid has a wide range of applications starting from its undissociated form, and its production using cell factories requires stress-tolerant microbial hosts. The interspecies hybrid yeast Zygosaccharomyces parabailii has great potential to be exploited as a novel host for lactic acid production, due to high organic acid tolerance at low pH and a fermentative metabolism with a high growth rate. Here we used mRNA sequencing (RNA-seq) to analyze Z. parabailii's transcriptional response to lactic acid added exogenously, and we explore the biological mechanisms involved in tolerance. Z. parabailii contains two homeologous copies of most genes. Under lactic acid stress, the two genes in each homeolog pair tend to diverge in expression to a significantly greater extent than under control conditions, indicating that stress tolerance is facilitated by interactions between the two gene sets in the hybrid. Lactic acid induces downregulation of genes related to cell wall and plasma membrane functions, possibly altering the rate of diffusion of lactic acid into cells. Genes related to iron transport and redox processes were upregulated, suggesting an important role for respiratory functions and oxidative stress defense. We found differences in the expression profiles of genes putatively regulated by Haa1 and Aft1/Aft2, previously described as lactic acid responsive in Saccharomyces cerevisiae. Furthermore, formate dehydrogenase (FDH) genes form a lactic acid-responsive gene family that has been specifically amplified in Z. parabailii in comparison to other closely related species. Our study provides a useful starting point for the engineering of Z. parabailii as a host for lactic acid production. IMPORTANCE Hybrid yeasts are important in biotechnology because of their tolerance to harsh industrial conditions. The molecular mechanisms of tolerance can be studied by analyzing differential gene expression under conditions of interest and relating gene expression patterns to protein functions. However, hybrid organisms present a challenge to the standard use of mRNA sequencing (RNA-seq) to study transcriptional responses to stress, because their genomes contain two similar copies of almost every gene. Here we used stringent mapping methods and a high-quality genome sequence to study the transcriptional response to lactic acid stress in Zygosaccharomyces parabailii ATCC 60483, a natural interspecies hybrid yeast that contains two complete subgenomes that are approximately 7% divergent in sequence. Beyond the insights we gained into lactic acid tolerance in this study, the methods we developed will be broadly applicable to other yeast hybrid strains.
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27
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Kim M, Lim JW, Lee SK, Kim T. Nanoscale Hydrodynamic Film for Diffusive Mass Transport Control in Compartmentalized Microfluidic Chambers. Anal Chem 2017; 89:10286-10295. [DOI: 10.1021/acs.analchem.7b01966] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Minseok Kim
- Department
of Mechanical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Republic of Korea
| | - Ji Won Lim
- Department
of Biomedical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Republic of Korea
| | - Sung Kuk Lee
- Department
of Biomedical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Republic of Korea
- Department
of Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Republic of Korea
| | - Taesung Kim
- Department
of Mechanical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Republic of Korea
- Department
of Biomedical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Republic of Korea
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28
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Baek S, Kwon EY, Bae S, Cho B, Kim S, Hahn J. Improvement of
d
‐Lactic Acid Production in
Saccharomyces cerevisiae
Under Acidic Conditions by Evolutionary and Rational Metabolic Engineering. Biotechnol J 2017; 12. [DOI: 10.1002/biot.201700015] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 07/11/2017] [Indexed: 01/12/2023]
Affiliation(s)
- Seung‐Ho Baek
- School of Chemical and Biological EngineeringInstitute of Chemical ProcessesSeoul National UniversitySeoulRepublic of Korea
| | - Eunice Y. Kwon
- School of Chemical and Biological EngineeringInstitute of Chemical ProcessesSeoul National UniversitySeoulRepublic of Korea
| | - Sang‐Jeong Bae
- School of Chemical and Biological EngineeringInstitute of Chemical ProcessesSeoul National UniversitySeoulRepublic of Korea
| | - Bo‐Ram Cho
- School of Chemical and Biological EngineeringInstitute of Chemical ProcessesSeoul National UniversitySeoulRepublic of Korea
| | - Seon‐Young Kim
- Personalized Genomic Medicine Research CenterKRIBBDaejeonRepublic of Korea
| | - Ji‐Sook Hahn
- School of Chemical and Biological EngineeringInstitute of Chemical ProcessesSeoul National UniversitySeoulRepublic of Korea
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Casein Kinase I Isoform Hrr25 Is a Negative Regulator of Haa1 in the Weak Acid Stress Response Pathway in Saccharomyces cerevisiae. Appl Environ Microbiol 2017; 83:AEM.00672-17. [PMID: 28432100 DOI: 10.1128/aem.00672-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 04/15/2017] [Indexed: 11/20/2022] Open
Abstract
Haa1 is a transcription factor that adapts Saccharomyces cerevisiae cells to weak organic acid stresses by activating the expression of various genes. Many of these genes encode membrane proteins, such as TPO2 and YRO2 How Haa1 is activated by weak acids is not clear. Here, we show that casein kinase I isoform Hrr25 is an important negative regulator of Haa1. Haa1 is known to be multiply phosphorylated. We found that mutations in HRR25 lead to reduced Haa1 phosphorylation and increased expression of Haa1 target genes and that Hrr25 interacts with Haa1. The other three casein kinase I isoforms, Yck1, Yck2, and Yck3, do not seem to play critical roles in Haa1 regulation. Hrr25 has a 200-residue C-terminal region, including a proline- and glutamine-rich domain. Our data suggest that the C-terminal region of Hrr25 is required for normal inhibition of expression of Haa1 target genes TPO2 and YRO2 and is important for cell growth but is not required for cell morphogenesis. We propose that Hrr25 is an important regulator of cellular adaptation to weak acid stress by inhibiting Haa1 through phosphorylation.IMPORTANCE Our study has revealed the casein kinase I protein Hrr25 to be a negative regulator of Haa1, a transcription factor mediating the cellular response to stresses caused by weak acids. Many studies have focused on the target genes of Haa1 and their roles in weak acid stress responses, but little has been reported on the regulatory mechanism of Haa1. Weak acids, such as acetic acid, have long been used for food preservation by slowing down the growth of fungal species, including S. cerevisiae In the biofuel industry, acetic acid in the lignocellulosic hydrolysates limits the production of ethanol, which is undesirable. By understanding how Haa1 is regulated, we can make advances in the field of food sciences to better preserve food and engineer acetic acid-resistant strains that will increase productivity in the biofuel industry.
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30
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Evolutionary engineering reveals divergent paths when yeast is adapted to different acidic environments. Metab Eng 2017; 39:19-28. [DOI: 10.1016/j.ymben.2016.10.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 10/01/2016] [Accepted: 10/21/2016] [Indexed: 12/30/2022]
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31
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Henriques SF, Mira NP, Sá-Correia I. Genome-wide search for candidate genes for yeast robustness improvement against formic acid reveals novel susceptibility (Trk1 and positive regulators) and resistance (Haa1-regulon) determinants. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:96. [PMID: 28428821 PMCID: PMC5395885 DOI: 10.1186/s13068-017-0781-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 04/11/2017] [Indexed: 05/06/2023]
Abstract
BACKGROUND Formic acid is an inhibitory compound present in lignocellulosic hydrolysates. Understanding the complex molecular mechanisms underlying Saccharomyces cerevisiae tolerance to this weak acid at the system level is instrumental to guide synthetic pathway engineering for robustness improvement of industrial strains envisaging their use in lignocellulosic biorefineries. RESULTS This study was performed to identify, at a genome-wide scale, genes whose expression confers protection or susceptibility to formic acid, based on the screening of a haploid deletion mutant collection to search for these phenotypes in the presence of 60, 70 and 80 mM of this acid, at pH 4.5. This chemogenomic analysis allowed the identification of 172 determinants of tolerance and 41 determinants of susceptibility to formic acid. Clustering of genes required for maximal tolerance to this weak acid, based on their biological function, indicates an enrichment of those involved in intracellular trafficking and protein synthesis, cell wall and cytoskeleton organization, carbohydrate metabolism, lipid, amino acid and vitamin metabolism, response to stress, chromatin remodelling, transcription and internal pH homeostasis. Among these genes is HAA1 encoding the main transcriptional regulator of yeast transcriptome reprograming in response to acetic acid and genes of the Haa1-regulon; all demonstrated determinants of acetic acid tolerance. Among the genes that when deleted lead to increased tolerance to formic acid, TRK1, encoding the high-affinity potassium transporter and a determinant of resistance to acetic acid, was surprisingly found. Consistently, genes encoding positive regulators of Trk1 activity were also identified as formic acid susceptibility determinants, while a negative regulator confers protection. At a saturating K+ concentration of 20 mM, the deletion mutant trk1Δ was found to exhibit a much higher tolerance compared with the parental strain. Given that trk1Δ accumulates lower levels of radiolabelled formic acid, compared to the parental strain, it is hypothesized that Trk1 facilitates formic acid uptake into the yeast cell. CONCLUSIONS The list of genes resulting from this study shows a few marked differences from the list of genes conferring protection to acetic acid and provides potentially valuable information to guide improvement programmes for the development of more robust strains against formic acid.
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Affiliation(s)
- Sílvia F. Henriques
- Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - Nuno P. Mira
- Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - Isabel Sá-Correia
- Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
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GSF2 deletion increases lactic acid production by alleviating glucose repression in Saccharomyces cerevisiae. Sci Rep 2016; 6:34812. [PMID: 27708428 PMCID: PMC5052599 DOI: 10.1038/srep34812] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 09/20/2016] [Indexed: 01/02/2023] Open
Abstract
Improving lactic acid (LA) tolerance is important for cost-effective microbial production of LA under acidic fermentation conditions. Previously, we generated LA-tolerant D-LA-producing S. cerevisiae strain JHY5310 by laboratory adaptive evolution of JHY5210. In this study, we performed whole genome sequencing of JHY5310, identifying four loss-of-function mutations in GSF2, SYN8, STM1, and SIF2 genes, which are responsible for the LA tolerance of JHY5310. Among the mutations, a nonsense mutation in GSF2 was identified as the major contributor to the improved LA tolerance and LA production in JHY5310. Deletion of GSF2 in the parental strain JHY5210 significantly improved glucose uptake and D-LA production levels, while derepressing glucose-repressed genes including genes involved in the respiratory pathway. Therefore, more efficient generation of ATP and NAD+ via respiration might rescue the growth defects of the LA-producing strain, where ATP depletion through extensive export of lactate and proton is one of major reasons for the impaired growth. Accordingly, alleviation of glucose repression by deleting MIG1 or HXK2 in JHY5210 also improved D-LA production. GSF2 deletion could be applied to various bioprocesses where increasing biomass yield or respiratory flux is desirable.
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Overexpression of ESBP6 improves lactic acid resistance and production in Saccharomyces cerevisiae. J Biosci Bioeng 2016; 122:415-20. [DOI: 10.1016/j.jbiosc.2016.03.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 02/12/2016] [Accepted: 03/16/2016] [Indexed: 12/28/2022]
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Comparative transcriptome assembly and genome-guided profiling for Brettanomyces bruxellensis LAMAP2480 during p-coumaric acid stress. Sci Rep 2016; 6:34304. [PMID: 27678167 PMCID: PMC5039629 DOI: 10.1038/srep34304] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 09/07/2016] [Indexed: 11/08/2022] Open
Abstract
Brettanomyces bruxellensis has been described as the main contaminant yeast in wine production, due to its ability to convert the hydroxycinnamic acids naturally present in the grape phenolic derivatives, into volatile phenols. Currently, there are no studies in B. bruxellensis which explains the resistance mechanisms to hydroxycinnamic acids, and in particular to p-coumaric acid which is directly involved in alterations to wine. In this work, we performed a transcriptome analysis of B. bruxellensis LAMAP248rown in the presence and absence of p-coumaric acid during lag phase. Because of reported genetic variability among B. bruxellensis strains, to complement de novo assembly of the transcripts, we used the high-quality genome of B. bruxellensis AWRI1499, as well as the draft genomes of strains CBS2499 and0 g LAMAP2480. The results from the transcriptome analysis allowed us to propose a model in which the entrance of p-coumaric acid to the cell generates a generalized stress condition, in which the expression of proton pump and efflux of toxic compounds are induced. In addition, these mechanisms could be involved in the outflux of nitrogen compounds, such as amino acids, decreasing the overall concentration and triggering the expression of nitrogen metabolism genes.
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35
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Berterame NM, Porro D, Ami D, Branduardi P. Protein aggregation and membrane lipid modifications under lactic acid stress in wild type and OPI1 deleted Saccharomyces cerevisiae strains. Microb Cell Fact 2016; 15:39. [PMID: 26887851 PMCID: PMC4756461 DOI: 10.1186/s12934-016-0438-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 02/02/2016] [Indexed: 11/12/2022] Open
Abstract
Background Lactic acid is a versatile chemical platform with many different industrial applications. Yeasts have been demonstrated as attractive alternative to natural lactic acid producers since they can grow at low pH, allowing the direct purification of the product in the desired acidic form. However, when very high concentrations of organic acids are reached, the major limitation for a viable production is the toxic effect of the product. The accumulation in the cytosol of H+ and of the weak organic counter-anions triggers a cellular reprogramming. Here, the effects of lactic acid exposure on Saccharomycescerevisiae have been evaluated by Fourier transform infrared (FTIR) microspectroscopy. In addition to -omic techniques, describing these responses in terms of systems and networks, FTIR microspectroscopy allows a rapid acquisition of the cellular biochemical fingerprint, providing information on the major classes of macromolecules. Results FTIR analyses on Saccharomyces cerevisiae cells under lactic acid stress at low pH revealed some still uncharacterized traits: (1) a direct correlation between lactic acid exposure and a rearrangement in lipid hydrocarbon tails, together with a decrease in the signals of phosphatidylcholine (PC), one of the main components of cell membrane; (2) a rearrangement in the cell wall carbohydrates, including glucans and mannans (3) a significant yet transient protein aggregation, possibly responsible for the observed transient decrease of the growth rate. When repeated on the isogenic strain deleted in OPI1, encoding for a transcriptional repressor of genes involved in PC biosynthesis, FTIR analysis revealed that not only the PC levels were affected but also the cell membrane/wall composition and the accumulation of protein aggregates, resulting in higher growth rate in the presence of the stressing agent. Conclusions This work revealed novel effects evoked by lactic acid on cell membrane/wall composition and protein aggregation in S. cerevisiae cells. We consequently demonstrated that the targeted deletion of OPI1 resulted in improved lactic acid tolerance. Considering that stress response involves many and different cellular networks and regulations, most of which are still not implemented in modelling, these findings constitute valuable issues for interpreting cellular rewiring and for tailoring ameliorated cell factories for lactic acid production. Electronic supplementary material The online version of this article (doi:10.1186/s12934-016-0438-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nadia Maria Berterame
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, Milan, 20126, Italy.
| | - Danilo Porro
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, Milan, 20126, Italy. .,SYSBIO - Centre of Systems Biology, Milano and Roma, Italy.
| | - Diletta Ami
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, Milan, 20126, Italy. .,Department of Physics, University of Milano-Bicocca, Piazza della Scienza 3, Milan, 20126, Italy. .,Consorzio Nazionale Interuniversitario per le Scienze fisiche della Materia (CNISM) UdR Milano-Bicocca, Milan, 20126, Italy.
| | - Paola Branduardi
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, Milan, 20126, Italy.
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Stanojević-Nikolić S, Dimić G, Mojović L, Pejin J, Djukić-Vuković A, Kocić-Tanackov S. Antimicrobial Activity of Lactic Acid Against Pathogen and Spoilage Microorganisms. J FOOD PROCESS PRES 2015. [DOI: 10.1111/jfpp.12679] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | - Gordana Dimić
- Faculty of Technology; University of Novi Sad; Bulevar cara Lazara 1 Novi Sad 21 000 Serbia
| | - Ljiljana Mojović
- Faculty of Technology and Metallurgy; University of Belgrade; Belgrade Serbia
| | - Jelena Pejin
- Faculty of Technology; University of Novi Sad; Bulevar cara Lazara 1 Novi Sad 21 000 Serbia
| | | | - Sunčica Kocić-Tanackov
- Faculty of Technology; University of Novi Sad; Bulevar cara Lazara 1 Novi Sad 21 000 Serbia
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Marques WL, Raghavendran V, Stambuk BU, Gombert AK. Sucrose and Saccharomyces cerevisiae: a relationship most sweet. FEMS Yeast Res 2015; 16:fov107. [PMID: 26658003 DOI: 10.1093/femsyr/fov107] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/06/2015] [Indexed: 12/16/2022] Open
Abstract
Sucrose is an abundant, readily available and inexpensive substrate for industrial biotechnology processes and its use is demonstrated with much success in the production of fuel ethanol in Brazil. Saccharomyces cerevisiae, which naturally evolved to efficiently consume sugars such as sucrose, is one of the most important cell factories due to its robustness, stress tolerance, genetic accessibility, simple nutrient requirements and long history as an industrial workhorse. This minireview is focused on sucrose metabolism in S. cerevisiae, a rather unexplored subject in the scientific literature. An analysis of sucrose availability in nature and yeast sugar metabolism was performed, in order to understand the molecular background that makes S. cerevisiae consume this sugar efficiently. A historical overview on the use of sucrose and S. cerevisiae by humans is also presented considering sugarcane and sugarbeet as the main sources of this carbohydrate. Physiological aspects of sucrose consumption are compared with those concerning other economically relevant sugars. Also, metabolic engineering efforts to alter sucrose catabolism are presented in a chronological manner. In spite of its extensive use in yeast-based industries, a lot of basic and applied research on sucrose metabolism is imperative, mainly in fields such as genetics, physiology and metabolic engineering.
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Affiliation(s)
- Wesley Leoricy Marques
- Department of Chemical Engineering, University of São Paulo, São Paulo-SP, 05424-970, Brazil School of Food Engineering, University of Campinas, Campinas-SP, 13083-862, Brazil
| | | | - Boris Ugarte Stambuk
- Department of Biochemistry, Federal University of Santa Catarina, Florianópolis-SC, 88040-900, Brazil
| | - Andreas Karoly Gombert
- Department of Chemical Engineering, University of São Paulo, São Paulo-SP, 05424-970, Brazil School of Food Engineering, University of Campinas, Campinas-SP, 13083-862, Brazil
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Baek SH, Kwon EY, Kim YH, Hahn JS. Metabolic engineering and adaptive evolution for efficient production of D-lactic acid in Saccharomyces cerevisiae. Appl Microbiol Biotechnol 2015; 100:2737-48. [PMID: 26596574 DOI: 10.1007/s00253-015-7174-0] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 10/23/2015] [Accepted: 11/10/2015] [Indexed: 12/01/2022]
Abstract
There is an increasing demand for microbial production of lactic acid (LA) as a monomer of biodegradable poly lactic acid (PLA). Both optical isomers, D-LA and L-LA, are required to produce stereocomplex PLA with improved properties. In this study, we developed Saccharomyces cerevisiae strains for efficient production of D-LA. D-LA production was achieved by expressing highly stereospecific D-lactate dehydrogenase gene (ldhA, LEUM_1756) from Leuconostoc mesenteroides subsp. mesenteroides ATCC 8293 in S. cerevisiae lacking natural LA production activity. D-LA consumption after glucose depletion was inhibited by deleting DLD1 encoding D-lactate dehydrogenase and JEN1 encoding monocarboxylate transporter. In addition, ethanol production was reduced by deleting PDC1 and ADH1 genes encoding major pyruvate decarboxylase and alcohol dehydrogenase, respectively, and glycerol production was eliminated by deleting GPD1 and GPD2 genes encoding glycerol-3-phosphate dehydrogenase. LA tolerance of the engineered D-LA-producing strain was enhanced by adaptive evolution and overexpression of HAA1 encoding a transcriptional activator involved in weak acid stress response, resulting in effective D-LA production up to 48.9 g/L without neutralization. In a flask fed-batch fermentation under neutralizing condition, our evolved strain produced 112.0 g/L D-LA with a yield of 0.80 g/g glucose and a productivity of 2.2 g/(L · h).
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Affiliation(s)
- Seung-Ho Baek
- School of Chemical and Biological Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Eunice Y Kwon
- School of Chemical and Biological Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Yong Hwan Kim
- Department of Chemical Engineering, Kwangwoon University, 20 Gwangun-ro, Nowon-gu, Seoul, 01897, Republic of Korea
| | - Ji-Sook Hahn
- School of Chemical and Biological Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
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Improvement of glucose uptake rate and production of target chemicals by overexpressing hexose transporters and transcriptional activator Gcr1 in Saccharomyces cerevisiae. Appl Environ Microbiol 2015; 81:8392-401. [PMID: 26431967 DOI: 10.1128/aem.02056-15] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 09/25/2015] [Indexed: 01/03/2023] Open
Abstract
Metabolic engineering to increase the glucose uptake rate might be beneficial to improve microbial production of various fuels and chemicals. In this study, we enhanced the glucose uptake rate in Saccharomyces cerevisiae by overexpressing hexose transporters (HXTs). Among the 5 tested HXTs (Hxt1, Hxt2, Hxt3, Hxt4, and Hxt7), overexpression of high-affinity transporter Hxt7 was the most effective in increasing the glucose uptake rate, followed by moderate-affinity transporters Hxt2 and Hxt4. Deletion of STD1 and MTH1, encoding corepressors of HXT genes, exerted differential effects on the glucose uptake rate, depending on the culture conditions. In addition, improved cell growth and glucose uptake rates could be achieved by overexpression of GCR1, which led to increased transcription levels of HXT1 and ribosomal protein genes. All genetic modifications enhancing the glucose uptake rate also increased the ethanol production rate in wild-type S. cerevisiae. Furthermore, the growth-promoting effect of GCR1 overexpression was successfully applied to lactic acid production in an engineered lactic acid-producing strain, resulting in a significant improvement of productivity and titers of lactic acid production under acidic fermentation conditions.
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Comparative Proteomic Insights into the Lactate Responses of Halophilic Salinicoccus roseus W12. Sci Rep 2015; 5:13776. [PMID: 26358621 PMCID: PMC4566078 DOI: 10.1038/srep13776] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 08/05/2015] [Indexed: 12/13/2022] Open
Abstract
Extremophiles use adaptive mechanisms to survive in extreme environments, which is of great importance for several biotechnological applications. A halophilic strain, Salinicoccus roseus W12, was isolated from salt lake in Inner Mongolia, China in this study. The ability of the strain to survive under high sodium conditions (including 20% sodium lactate or 25% sodium chloride, [w/v]) made it an ideal host to screen for key factors related to sodium lactate resistance. The proteomic responses to lactate were studied using W12 cells cultivated with or without lactate stress. A total of 1,656 protein spots in sodium lactate-treated culture and 1,843 spots in NaCl-treated culture were detected by 2-dimensional gel electrophoresis, and 32 of 120 significantly altered protein spots (fold change > 2, p < 0.05) were identified by matrix-assisted laser-desorption ionization time-of-flight mass spectrometry. Among 21 successfully identified spots, 19 proteins were upregulated and 2 were downregulated. The identified proteins are mainly involved in metabolism, cellular processes and signaling, and information storage and processing. Transcription studies confirmed that most of the encoding genes were upregulated after the cells were exposed to lactate in 10 min. Cross-protecting and energy metabolism-related proteins played an important role in lactate tolerance for S. roseus W12.
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Dong SJ, Lin XH, Li H. Regulation of Lactobacillus plantarum contamination on the carbohydrate and energy related metabolisms of Saccharomyces cerevisiae during bioethanol fermentation. Int J Biochem Cell Biol 2015; 68:33-41. [PMID: 26279142 DOI: 10.1016/j.biocel.2015.08.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 08/11/2015] [Indexed: 10/23/2022]
Abstract
During the industrial bioethanol fermentation, Saccharomyces cerevisiae cells are often stressed by bacterial contaminants, especially lactic acid bacteria. Generally, lactic acid bacteria contamination can inhibit S. cerevisiae cell growth through secreting lactic acid and competing with yeast cells for micronutrients and living space. However, whether are there still any other influences of lactic acid bacteria on yeast or not? In this study, Lactobacillus plantarum ATCC 8014 was co-cultivated with S. cerevisiae S288c to mimic the L. plantarum contamination in industrial bioethanol fermentation. The contaminative L. plantarum-associated expression changes of genes involved in carbohydrate and energy related metabolisms in S. cerevisiae cells were determined by quantitative real-time polymerase chain reaction to evaluate the influence of L. plantarum on carbon source utilization and energy related metabolism in yeast cells during bioethanol fermentation. Contaminative L. plantarum influenced the expression of most of genes which are responsible for encoding key enzymes involved in glucose related metabolisms in S. cerevisiae. Specific for, contaminated L. plantarum inhibited EMP pathway but promoted TCA cycle, glyoxylate cycle, HMP, glycerol synthesis pathway, and redox pathway in S. cerevisiae cells. In the presence of L. plantarum, the carbon flux in S. cerevisiae cells was redistributed from fermentation to respiratory and more reducing power was produced to deal with the excess NADH. Moreover, L. plantarum contamination might confer higher ethanol tolerance to yeast cells through promoting accumulation of glycerol. These results also highlighted our knowledge about relationship between contaminative lactic acid bacteria and S. cerevisiae during bioethanol fermentation.
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Affiliation(s)
- Shi-Jun Dong
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Xiang-Hua Lin
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
| | - Hao Li
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.
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Sheibani S, Jones NK, Eid R, Gharib N, Arab NTT, Titorenko V, Vali H, Young PA, Greenwood MT. Inhibition of stress mediated cell death by human lactate dehydrogenase B in yeast. FEMS Yeast Res 2015; 15:fov032. [DOI: 10.1093/femsyr/fov032] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 05/19/2015] [Indexed: 12/11/2022] Open
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Danziger SA, Reiss DJ, Ratushny AV, Smith JJ, Plaisier CL, Aitchison JD, Baliga NS. Bicluster Sampled Coherence Metric (BSCM) provides an accurate environmental context for phenotype predictions. BMC SYSTEMS BIOLOGY 2015; 9 Suppl 2:S1. [PMID: 25881257 PMCID: PMC4407105 DOI: 10.1186/1752-0509-9-s2-s1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Background Biclustering is a popular method for identifying under which experimental conditions biological signatures are co-expressed. However, the general biclustering problem is NP-hard, offering room to focus algorithms on specific biological tasks. We hypothesize that conditional co-regulation of genes is a key factor in determining cell phenotype and that accurately segregating conditions in biclusters will improve such predictions. Thus, we developed a bicluster sampled coherence metric (BSCM) for determining which conditions and signals should be included in a bicluster. Results Our BSCM calculates condition and cluster size specific p-values, and we incorporated these into the popular integrated biclustering algorithm cMonkey. We demonstrate that incorporation of our new algorithm significantly improves bicluster co-regulation scores (p-value = 0.009) and GO annotation scores (p-value = 0.004). Additionally, we used a bicluster based signal to predict whether a given experimental condition will result in yeast peroxisome induction. Using the new algorithm, the classifier accuracy improves from 41.9% to 76.1% correct. Conclusions We demonstrate that the proposed BSCM helps determine which signals ought to be co-clustered, resulting in more accurately assigned bicluster membership. Furthermore, we show that BSCM can be extended to more accurately detect under which experimental conditions the genes are co-clustered. Features derived from this more accurate analysis of conditional regulation results in a dramatic improvement in the ability to predict a cellular phenotype in yeast. The latest cMonkey is available for download at https://github.com/baliga-lab/cmonkey2. The experimental data and source code featured in this paper is available http://AitchisonLab.com/BSCM. BSCM has been incorporated in the official cMonkey release.
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44
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Carvalho-Netto OV, Carazzolle MF, Mofatto LS, Teixeira PJPL, Noronha MF, Calderón LAL, Mieczkowski PA, Argueso JL, Pereira GAG. Saccharomyces cerevisiae transcriptional reprograming due to bacterial contamination during industrial scale bioethanol production. Microb Cell Fact 2015; 14:13. [PMID: 25633848 PMCID: PMC4318157 DOI: 10.1186/s12934-015-0196-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Accepted: 01/13/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The bioethanol production system used in Brazil is based on the fermentation of sucrose from sugarcane feedstock by highly adapted strains of the yeast Saccharomyces cerevisiae. Bacterial contaminants present in the distillery environment often produce yeast-bacteria cellular co-aggregation particles that resemble yeast-yeast cell adhesion (flocculation). The formation of such particles is undesirable because it slows the fermentation kinetics and reduces the overall bioethanol yield. RESULTS In this study, we investigated the molecular physiology of one of the main S. cerevisiae strains used in Brazilian bioethanol production, PE-2, under two contrasting conditions: typical fermentation, when most yeast cells are in suspension, and co-aggregated fermentation. The transcriptional profile of PE-2 was assessed by RNA-seq during industrial scale fed-batch fermentation. Comparative analysis between the two conditions revealed transcriptional profiles that were differentiated primarily by a deep gene repression in the co-aggregated samples. The data also indicated that Lactobacillus fermentum was likely the main bacterial species responsible for cellular co-aggregation and for the high levels of organic acids detected in the samples. CONCLUSIONS Here, we report the high-resolution gene expression profiling of strain PE-2 during industrial-scale fermentations and the transcriptional reprograming observed under co-aggregation conditions. This dataset constitutes an important resource that can provide support for further development of this key yeast biocatalyst.
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Affiliation(s)
- Osmar V Carvalho-Netto
- Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil.
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, USA.
| | - Marcelo F Carazzolle
- Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil.
| | - Luciana S Mofatto
- Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil.
| | - Paulo J P L Teixeira
- Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil.
| | - Melline F Noronha
- Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil.
| | - Luige A L Calderón
- Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil.
| | | | - Juan Lucas Argueso
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, USA.
| | - Gonçalo A G Pereira
- Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil.
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Della-Bianca BE, de Hulster E, Pronk JT, van Maris AJ, Gombert AK. Physiology of the fuel ethanol strainSaccharomyces cerevisiaePE-2 at low pH indicates a context-dependent performance relevant for industrial applications. FEMS Yeast Res 2014; 14:1196-205. [DOI: 10.1111/1567-1364.12217] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 09/04/2014] [Accepted: 09/23/2014] [Indexed: 12/27/2022] Open
Affiliation(s)
| | - Erik de Hulster
- Department of Biotechnology; Delft University of Technology; Delft The Netherlands
| | - Jack T. Pronk
- Department of Biotechnology; Delft University of Technology; Delft The Netherlands
| | | | - Andreas K. Gombert
- Department of Chemical Engineering; University of Sao Paulo; São Paulo-SP Brazil
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Putra MD, Abasaeed AE, Atiyeh HK, Al-Zahrani SM, Gaily MH, Sulieman AK, Zeinelabdeen MA. Kinetic Modeling and Enhanced Production of Fructose and Ethanol From Date Fruit Extract. CHEM ENG COMMUN 2014. [DOI: 10.1080/00986445.2014.968711] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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47
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Mojzita D, Oja M, Rintala E, Wiebe M, Penttilä M, Ruohonen L. Transcriptome of Saccharomyces cerevisiae during production of D-xylonate. BMC Genomics 2014; 15:763. [PMID: 25192596 PMCID: PMC4176587 DOI: 10.1186/1471-2164-15-763] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 08/29/2014] [Indexed: 11/24/2022] Open
Abstract
Background Production of D-xylonate by the yeast S. cerevisiae provides an example of bioprocess development for sustainable production of value-added chemicals from cheap raw materials or side streams. Production of D-xylonate may lead to considerable intracellular accumulation of D-xylonate and to loss of viability during the production process. In order to understand the physiological responses associated with D-xylonate production, we performed transcriptome analyses during D-xylonate production by a robust recombinant strain of S. cerevisiae which produces up to 50 g/L D-xylonate. Results Comparison of the transcriptomes of the D-xylonate producing and the control strain showed considerably higher expression of the genes controlled by the cell wall integrity (CWI) pathway and of some genes previously identified as up-regulated in response to other organic acids in the D-xylonate producing strain. Increased phosphorylation of Slt2 kinase in the D-xylonate producing strain also indicated that D-xylonate production caused stress to the cell wall. Surprisingly, genes encoding proteins involved in translation, ribosome structure and RNA metabolism, processes which are commonly down-regulated under conditions causing cellular stress, were up-regulated during D-xylonate production, compared to the control. The overall transcriptional responses were, therefore, very dissimilar to those previously reported as being associated with stress, including stress induced by organic acid treatment or production. Quantitative PCR analyses of selected genes supported the observations made in the transcriptomic analysis. In addition, consumption of ethanol was slower and the level of trehalose was lower in the D-xylonate producing strain, compared to the control. Conclusions The production of organic acids has a major impact on the physiology of yeast cells, but the transcriptional responses to presence or production of different acids differs considerably, being much more diverse than responses to other stresses. D-Xylonate production apparently imposed considerable stress on the cell wall. Transcriptional data also indicated that activation of the PKA pathway occurred during D-xylonate production, leaving cells unable to adapt normally to stationary phase. This, together with intracellular acidification, probably contributes to cell death. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-763) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Dominik Mojzita
- VTT Technical Research Centre of Finland, P,O, Box 1000, Espoo FI-02044 VTT, Finland.
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Nuclear localization of Haa1, which is linked to its phosphorylation status, mediates lactic acid tolerance in Saccharomyces cerevisiae. Appl Environ Microbiol 2014; 80:3488-95. [PMID: 24682296 DOI: 10.1128/aem.04241-13] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Improvement of the lactic acid resistance of the yeast Saccharomyces cerevisiae is important for the application of the yeast in industrial production of lactic acid from renewable resources. However, we still do not know the precise mechanisms of the lactic acid adaptation response in yeast and, consequently, lack effective approaches for improving its lactic acid tolerance. To enhance our understanding of the adaptation response, we screened for S. cerevisiae genes that confer enhanced lactic acid resistance when present in multiple copies and identified the transcriptional factor Haa1 as conferring resistance to toxic levels of lactic acid when overexpressed. The enhanced tolerance probably results from increased expression of its target genes. When cells that expressed Haa1 only from the endogenous promoter were exposed to lactic acid stress, the main subcellular localization of Haa1 changed from the cytoplasm to the nucleus within 5 min. This nuclear accumulation induced upregulation of the Haa1 target genes YGP1, GPG1, and SPI1, while the degree of Haa1 phosphorylation observed under lactic acid-free conditions decreased. Disruption of the exportin gene MSN5 led to accumulation of Haa1 in the nucleus even when no lactic acid was present. Since Msn5 was reported to interact with Haa1 and preferentially exports phosphorylated cargo proteins, our results suggest that regulation of the subcellular localization of Haa1, together with alteration of its phosphorylation status, mediates the adaptation to lactic acid stress in yeast.
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Transcriptome-based characterization of interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus in lactose-grown chemostat cocultures. Appl Environ Microbiol 2013; 79:5949-61. [PMID: 23872557 DOI: 10.1128/aem.01115-13] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mixed populations of Saccharomyces cerevisiae yeasts and lactic acid bacteria occur in many dairy, food, and beverage fermentations, but knowledge about their interactions is incomplete. In the present study, interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus, two microorganisms that co-occur in kefir fermentations, were studied during anaerobic growth on lactose. By combining physiological and transcriptome analysis of the two strains in the cocultures, five mechanisms of interaction were identified. (i) Lb. delbrueckii subsp. bulgaricus hydrolyzes lactose, which cannot be metabolized by S. cerevisiae, to galactose and glucose. Subsequently, galactose, which cannot be metabolized by Lb. delbrueckii subsp. bulgaricus, is excreted and provides a carbon source for yeast. (ii) In pure cultures, Lb. delbrueckii subsp. bulgaricus grows only in the presence of increased CO2 concentrations. In anaerobic mixed cultures, the yeast provides this CO2 via alcoholic fermentation. (iii) Analysis of amino acid consumption from the defined medium indicated that S. cerevisiae supplied alanine to the bacterium. (iv) A mild but significant low-iron response in the yeast transcriptome, identified by DNA microarray analysis, was consistent with the chelation of iron by the lactate produced by Lb. delbrueckii subsp. bulgaricus. (v) Transcriptome analysis of Lb. delbrueckii subsp. bulgaricus in mixed cultures showed an overrepresentation of transcripts involved in lipid metabolism, suggesting either a competition of the two microorganisms for fatty acids or a response to the ethanol produced by S. cerevisiae. This study demonstrates that chemostat-based transcriptome analysis is a powerful tool to investigate microbial interactions in mixed populations.
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Suzuki T, Sakamoto T, Sugiyama M, Ishida N, Kambe H, Obata S, Kaneko Y, Takahashi H, Harashima S. Disruption of multiple genes whose deletion causes lactic-acid resistance improves lactic-acid resistance and productivity in Saccharomyces cerevisiae. J Biosci Bioeng 2013; 115:467-74. [PMID: 23290995 DOI: 10.1016/j.jbiosc.2012.11.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 10/19/2012] [Accepted: 11/19/2012] [Indexed: 11/28/2022]
Abstract
To create strains that have high productivity of lactic acid without neutralization, a genome-wide screening for strains showing hyper-resistance to 6% l-lactic acid (pH 2.6) was performed using the gene deletion collection of Saccharomyces cerevisiae. We identified 94 genes whose disruption led to resistance to 6% lactic acid in rich medium. We also found that multiple combinations of Δdse2, Δscw11, Δeaf3, and/or Δsed1 disruption led to enhanced resistance to lactic acid depending upon their combinations. In particular, the quadruple disruptant Δdse2Δscw11Δeaf3Δsed1 grew well in 6% lactic acid with the shortest lag phase. We then introduced an exogenous lactate dehydrogenase gene (LDH) into those single and multiple disruptants to evaluate their productivity of lactic acid. It was found that the quadruple disruptant displaying highest lactic-acid resistance showed a 27% increase of lactic-acid productivity as compared with the LDH-harboring wild-type strain. These observations suggest that disruption of multiple genes whose deletion leads to lactic-acid resistance is an effective way to enhance resistance to lactic acid, leading to high lactic-acid productivity without neutralization.
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Affiliation(s)
- Toshihiro Suzuki
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
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