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Caballero-Sanchez L, Lázaro-Mixteco PE, Vargas-Tah A, Castro-Montoya AJ. Pilot-scale bioethanol production from the starch of avocado seeds using a combination of dilute acid-based hydrolysis and alcoholic fermentation by Saccharomyces cerevisiae. Microb Cell Fact 2023; 22:119. [PMID: 37386435 DOI: 10.1186/s12934-023-02110-5] [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: 12/05/2022] [Accepted: 05/01/2023] [Indexed: 07/01/2023] Open
Abstract
BACKGROUND A processing methodology of raw starch extraction from avocado seeds (ASs) and a sequential hydrolysis and fermentation bioprocess in just a few steps was successfully obtained for the bioethanol production by a single yeast Saccharomyces cerevisiae strain and this research was also to investigate the optimum conditions for the pretreatment of biomass and technical procedures for the production of bioethanol. It successfully resulted in high yields and productivity of all the experiments from the laboratory scale and the pilot plant. Ethanol yields from pretreated starch are comparable with those in commercial industries that use molasses and hydrolyzed starch as raw materials. RESULTS Before the pilot-scale bioethanol production, studies of starch extraction and dilute sulfuric acid-based pretreatment was carefully conducted. The amount of starch extracted from dry and fresh avocado seed was 16.85 g ± 0.34 g and 29.79 ± 3.18 g of dry starch, representing a yield of ∼17% and 30%, respectively. After a dilute sulfuric acid pretreatment of starch, the released reducing sugars (RRS) were obtained and the hydrolysate slurries containing glucose (109.79 ± 1.14 g/L), xylose (0.99 ± 0.06 g/L), and arabinose (0.38 ± 0.01 g/L). The efficiency of total sugar conversion was 73.40%, with a productivity of 9.26 g/L/h. The ethanol fermentation in a 125 mL flask fermenter showed that Saccharomyces cerevisiae (Fali, active dry yeast) produced the maximum ethanol concentration, pmax at 49.05 g/L (6.22% v/v) with a yield coefficient, Yp/s of 0.44 gEthanol/gGlucose, a productivity or production rate, rp at 2.01 g/L/h and an efficiency, Ef of 85.37%. The pilot scale experiments of the ethanol fermentation using the 40-L fermenter were also successfully achieved with essentially good results. The values of pmax,Yp/s, rp, and Ef of the 40-L scale were at 50.94 g/L (6.46% v/v), 0.45 gEthanol/gGlucose, 2.11 g/L/h, and 88.74%, respectively. Because of using raw starch, major by-products, i.e., acetic acid in the two scales were very low, in ranges of 0.88-2.45 g/L, and lactic acid was not produced, which are less than those values in the industries. CONCLUSIONS The sequential hydrolysis and fermentation process of two scales for ethanol production using the combination of hydrolysis by utilizing dilute sulfuric acid-based pretreatment and fermentation by a single yeast Saccharomyces cerevisiae strain is practicable and feasible for realistic and effective scale-up strategies of bioethanol production from the starch of avocado seeds.
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Affiliation(s)
- Luis Caballero-Sanchez
- Posgrado de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Francisco J. Múgica S/N, Ciudad Universitaria, 58030, Morelia, Mich, México
| | - Pedro E Lázaro-Mixteco
- Facultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Francisco J. Múgica S/N, Ciudad Universitaria, 58030, Morelia, Mich, México
| | - Alejandra Vargas-Tah
- Facultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Francisco J. Múgica S/N, Ciudad Universitaria, 58030, Morelia, Mich, México.
| | - Agustín J Castro-Montoya
- Posgrado de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Francisco J. Múgica S/N, Ciudad Universitaria, 58030, Morelia, Mich, México.
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2
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Nalabothu RL, Fisher KJ, LaBella AL, Meyer TA, Opulente DA, Wolters JF, Rokas A, Hittinger CT. Codon Optimization Improves the Prediction of Xylose Metabolism from Gene Content in Budding Yeasts. Mol Biol Evol 2023; 40:msad111. [PMID: 37154525 PMCID: PMC10263009 DOI: 10.1093/molbev/msad111] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 02/28/2023] [Accepted: 05/04/2023] [Indexed: 05/10/2023] Open
Abstract
Xylose is the second most abundant monomeric sugar in plant biomass. Consequently, xylose catabolism is an ecologically important trait for saprotrophic organisms, as well as a fundamentally important trait for industries that hope to convert plant mass to renewable fuels and other bioproducts using microbial metabolism. Although common across fungi, xylose catabolism is rare within Saccharomycotina, the subphylum that contains most industrially relevant fermentative yeast species. The genomes of several yeasts unable to consume xylose have been previously reported to contain the full set of genes in the XYL pathway, suggesting the absence of a gene-trait correlation for xylose metabolism. Here, we measured growth on xylose and systematically identified XYL pathway orthologs across the genomes of 332 budding yeast species. Although the XYL pathway coevolved with xylose metabolism, we found that pathway presence only predicted xylose catabolism about half of the time, demonstrating that a complete XYL pathway is necessary, but not sufficient, for xylose catabolism. We also found that XYL1 copy number was positively correlated, after phylogenetic correction, with xylose utilization. We then quantified codon usage bias of XYL genes and found that XYL3 codon optimization was significantly higher, after phylogenetic correction, in species able to consume xylose. Finally, we showed that codon optimization of XYL2 was positively correlated, after phylogenetic correction, with growth rates in xylose medium. We conclude that gene content alone is a weak predictor of xylose metabolism and that using codon optimization enhances the prediction of xylose metabolism from yeast genome sequence data.
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Affiliation(s)
- Rishitha L Nalabothu
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI
| | - Kaitlin J Fisher
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- Department of Biological Sciences, State University of New York at Oswego, Oswego, NY
| | - Abigail Leavitt LaBella
- Department of Biological Sciences, Vanderbilt University, Nashville, TN
- Evolutionary Studies Initiative, Vanderbilt University, Nashville, TN
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, NC
| | - Taylor A Meyer
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI
| | - Dana A Opulente
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI
- Department of Biology, Villanova University, Villanova, PA
| | - John F Wolters
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Nashville, TN
- Evolutionary Studies Initiative, Vanderbilt University, Nashville, TN
| | - Chris Todd Hittinger
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI
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3
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Fermentation of Dairy-Relevant Sugars by Saccharomyces, Kluyveromyces, and Brettanomyces: An Exploratory Study with Implications for the Utilization of Acid Whey, Part II. FERMENTATION-BASEL 2022. [DOI: 10.3390/fermentation8060257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In Greek-style yogurt production, every kilogram of product yields 2 to 3 kg of acid whey (YAW); this coproduct’s composition and low pH pose challenges for its proper valorization and reinsertion into the food supply chain. However, 240 mL of YAW contains over 9 g of lactose and represents a good source of minerals; these traits can be leveraged to develop nutritious fermented beverages. The purpose of this study is to investigate the aerobic fermentation of dairy sugars by different yeasts by characterizing these processes and their products. This will determine whether such methods provide viable options for the production of acetic-acid-containing beverages from YAW. To achieve this, yeast nitrogen base was used to prepare four growth media formulations, each supplemented with lactose, glucose, galactose, or a 1:1 mix of glucose and galactose (GLU:GAL), and each adjusted to a pH of 4.20. Fermentations were performed by pure cultures of S. cerevisiae, K. marxianus, B. claussenii, or B. bruxellensis, and were held at 25 °C with agitation at 185 rpm. For each treatment, density, pH, and microbial enumeration were measured over time to obtain process profiles, while ethanol, organic acids, and sugars were analyzed at the beginning and the end of each fermentation via HPLC, to determine resulting products. ANOVA and Tukey’s honest significant difference test at a significance level of 0.05 were used to compare residual sugars and fermentation products. Variable rates of sugar consumption were observed for each species. In GLU:GAL, B. claussenii consumed all of the glucose, left behind most of the galactose, and produced a high concentration of acetic acid. These results suggest the potential to develop versatile processes that target glucose for acetic acid production, while leaving available galactose to confer products with prebiotic properties. The development of processes for the conversion of YAW into beverages with organic acids and other healthful components not only aligns with consumers’ demands for better-for-you products, but also promotes the valorization of this otherwise underutilized dairy coproduct.
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4
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Procópio DP, Kendrick E, Goldbeck R, Damasio ARDL, Franco TT, Leak DJ, Jin YS, Basso TO. Xylo-Oligosaccharide Utilization by Engineered Saccharomyces cerevisiae to Produce Ethanol. Front Bioeng Biotechnol 2022; 10:825981. [PMID: 35242749 PMCID: PMC8886126 DOI: 10.3389/fbioe.2022.825981] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/18/2022] [Indexed: 11/26/2022] Open
Abstract
The engineering of xylo-oligosaccharide-consuming Saccharomyces cerevisiae strains is a promising approach for more effective utilization of lignocellulosic biomass and the development of economic industrial fermentation processes. Extending the sugar consumption range without catabolite repression by including the metabolism of oligomers instead of only monomers would significantly improve second-generation ethanol production This review focuses on different aspects of the action mechanisms of xylan-degrading enzymes from bacteria and fungi, and their insertion in S. cerevisiae strains to obtain microbial cell factories able of consume these complex sugars and convert them to ethanol. Emphasis is given to different strategies for ethanol production from both extracellular and intracellular xylo-oligosaccharide utilization by S. cerevisiae strains. The suitability of S. cerevisiae for ethanol production combined with its genetic tractability indicates that it can play an important role in xylan bioconversion through the heterologous expression of xylanases from other microorganisms.
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Affiliation(s)
- Dielle Pierotti Procópio
- Department of Chemical Engineering, Escola Politécnica, University of São Paulo, São Paulo, Brazil
| | - Emanuele Kendrick
- Department of Biology and Biochemistry, Faculty of Sciences, University of Bath, Bath, United Kingdom
| | - Rosana Goldbeck
- School of Food Engineering, University of Campinas, Campinas, Brazil
| | | | - Telma Teixeira Franco
- Interdisciplinary Center of Energy Planning, University of Campinas, Campinas, Brazil
- School of Chemical Engineering, University of Campinas, Campinas, Brazil
| | - David J. Leak
- Department of Biology and Biochemistry, Faculty of Sciences, University of Bath, Bath, United Kingdom
| | - Yong-Su Jin
- DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, IL, United States
- Department of Food Science and Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Thiago Olitta Basso
- Department of Chemical Engineering, Escola Politécnica, University of São Paulo, São Paulo, Brazil
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5
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Leonel LV, Arruda PV, Chandel AK, Felipe MGA, Sene L. Kluyveromyces marxianus: a potential biocatalyst of renewable chemicals and lignocellulosic ethanol production. Crit Rev Biotechnol 2021; 41:1131-1152. [PMID: 33938342 DOI: 10.1080/07388551.2021.1917505] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Kluyveromyces marxianus is an ascomycetous yeast which has shown promising results in cellulosic ethanol and renewable chemicals production. It can survive on a variety of carbon sources under industrially favorable conditions due to its fast growth rate, thermotolerance, and acid tolerance. K. marxianus, is generally regarded as a safe (GRAS) microorganism, is widely recognized as a powerhouse for the production of heterologous proteins and is accepted by the US Food and Drug Administration (USFDA) for its pharmaceutical and food applications. Since lignocellulosic hydrolysates are comprised of diverse monomeric sugars, oligosaccharides and potential metabolism inhibiting compounds, this microorganism can play a pivotal role as it can grow on lignocellulosic hydrolysates coping with vegetal cell wall derived inhibitors. Furthermore, advancements in synthetic biology, for example CRISPR-Cas9 (clustered regularly interspaced short palindromic repeats with Cas9)-mediated genome editing, will enable development of an engineered yeast for the production of biochemicals and biopharmaceuticals having a myriad of industrial applications. Genetic engineering companies such as Cargill, Ginkgo Bioworks, DuPont, Global Yeast, Genomatica, and several others are actively working to develop designer yeasts. Given the important traits and properties of K. marxianus, these companies may find it to be a suitable biocatalyst for renewable chemicals and fuel production on the large scale. This paper reviews the recent progress made with K. marxianus biotechnology for sustainable production of ethanol, and other products utilizing lignocellulosic sugars.
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Affiliation(s)
- L V Leonel
- Center of Exact and Technological Sciences - CCET, State University of West Paraná, Cascavel, Brazil
| | - P V Arruda
- Department of Bioprocess Engineering and Biotechnology - COEBB/TD, Federal University of Technology - Paraná (UTFPR), Toledo, Brazil
| | - A K Chandel
- Department of Biotechnology, School of Engineering of Lorena - EEL, University of São Paulo, Lorena, Brazil
| | - M G A Felipe
- Department of Biotechnology, School of Engineering of Lorena - EEL, University of São Paulo, Lorena, Brazil
| | - L Sene
- Center of Exact and Technological Sciences - CCET, State University of West Paraná, Cascavel, Brazil
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6
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Ruchala J, Sibirny AA. Pentose metabolism and conversion to biofuels and high-value chemicals in yeasts. FEMS Microbiol Rev 2020; 45:6034013. [PMID: 33316044 DOI: 10.1093/femsre/fuaa069] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 12/09/2020] [Indexed: 12/15/2022] Open
Abstract
Pentose sugars are widespread in nature and two of them, D-xylose and L-arabinose belong to the most abundant sugars being the second and third by abundance sugars in dry plant biomass (lignocellulose) and in general on planet. Therefore, it is not surprising that metabolism and bioconversion of these pentoses attract much attention. Several different pathways of D-xylose and L-arabinose catabolism in bacteria and yeasts are known. There are even more common and really ubiquitous though not so abundant pentoses, D-ribose and 2-deoxy-D-ribose, the constituents of all living cells. Thus, ribose metabolism is example of endogenous metabolism whereas metabolism of other pentoses, including xylose and L-arabinose, represents examples of the metabolism of foreign exogenous compounds which normally are not constituents of yeast cells. As a rule, pentose degradation by the wild-type strains of microorganisms does not lead to accumulation of high amounts of valuable substances; however, productive strains have been obtained by random selection and metabolic engineering. There are numerous reviews on xylose and (less) L-arabinose metabolism and conversion to high value substances; however, they mostly are devoted to bacteria or the yeast Saccharomyces cerevisiae. This review is devoted to reviewing pentose metabolism and bioconversion mostly in non-conventional yeasts, which naturally metabolize xylose. Pentose metabolism in the recombinant strains of S. cerevisiae is also considered for comparison. The available data on ribose, xylose, L-arabinose transport, metabolism, regulation of these processes, interaction with glucose catabolism and construction of the productive strains of high-value chemicals or pentose (ribose) itself are described. In addition, genome studies of the natural xylose metabolizing yeasts and available tools for their molecular research are reviewed. Metabolism of other pentoses (2-deoxyribose, D-arabinose, lyxose) is briefly reviewed.
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Affiliation(s)
- Justyna Ruchala
- Department of Microbiology and Molecular Genetics, University of Rzeszow, Zelwerowicza 4, Rzeszow 35-601, Poland.,Department of Molecular Genetics and Biotechnology, Institute of Cell Biology NAS of Ukraine, Drahomanov Street, 14/16, Lviv 79005, Ukraine
| | - Andriy A Sibirny
- Department of Microbiology and Molecular Genetics, University of Rzeszow, Zelwerowicza 4, Rzeszow 35-601, Poland.,Department of Molecular Genetics and Biotechnology, Institute of Cell Biology NAS of Ukraine, Drahomanov Street, 14/16, Lviv 79005, Ukraine
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7
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Chacón-Vargas K, Torres J, Giles-Gómez M, Escalante A, Gibbons JG. Genomic profiling of bacterial and fungal communities and their predictive functionality during pulque fermentation by whole-genome shotgun sequencing. Sci Rep 2020; 10:15115. [PMID: 32934253 PMCID: PMC7493934 DOI: 10.1038/s41598-020-71864-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 08/12/2020] [Indexed: 02/06/2023] Open
Abstract
Pulque is a culturally important 4,000-year-old traditional Mexican fermented drink. Pulque is produced by adding fresh aguamiel (agave sap) to mature pulque, resulting in a mixture of microbial communities and chemical compositions. We performed shotgun metagenomic sequencing of five stages of pulque fermentation to characterize organismal and functional diversity. We identified 6 genera (Acinetobacter, Lactobacillus, Lactococcus, Leuconostoc, Saccharomyces and Zymomonas) and 10 species (Acinetobacter boissieri, Acinetobacter nectaris, Lactobacillus sanfranciscensis, Lactococcus lactis, Lactococcus piscium, Lactococcus plantarum, Leuconostoc citreum, Leuconostoc gelidum, Zymomonas mobilis and Saccharomyces cerevisiae) that were present ≥ 1% in at least one stage of pulque fermentation. The abundance of genera and species changed during fermentation and was associated with a decrease in sucrose and increases in ethanol and lactic acid, suggesting that resource competition shapes organismal diversity. We also predicted functional profiles, based on organismal gene content, for each fermentation stage and identified an abundance of genes associated with the biosynthesis of folate, an essential B-vitamin. Additionally, we investigated the evolutionary relationships of S. cerevisiae and Z. mobilis, two of the major microbial species found in pulque. For S. cerevisiae, we used a metagenomics assembly approach to identify S. cerevisiae scaffolds from pulque, and performed phylogenetic analysis of these sequences along with a collection of 158 S. cerevisiae strains. This analysis suggests that S. cerevisiae from pulque is most closely related to Asian strains isolated from sake and bioethanol. Lastly, we isolated and sequenced the whole-genomes of three strains of Z. mobilis from pulque and compared their relationship to seven previously sequenced isolates. Our results suggest pulque strains may represent a distinct lineage of Z. mobilis.
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Affiliation(s)
- Katherine Chacón-Vargas
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA, 01003, USA
- Department of Food Science, University of Massachusetts, Amherst, MA, 01003, USA
| | - Julian Torres
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Martha Giles-Gómez
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Adelfo Escalante
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
| | - John G Gibbons
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, MA, 01003, USA.
- Department of Food Science, University of Massachusetts, Amherst, MA, 01003, USA.
- Organismic and Evolutionary Biology Graduate Program, University of Massachusetts, Amherst, MA, 01003, USA.
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8
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9
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Bracher JM, Martinez-Rodriguez OA, Dekker WJC, Verhoeven MD, van Maris AJA, Pronk JT. Reassessment of requirements for anaerobic xylose fermentation by engineered, non-evolved Saccharomyces cerevisiae strains. FEMS Yeast Res 2019; 19:5106349. [PMID: 30252062 PMCID: PMC6240133 DOI: 10.1093/femsyr/foy104] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 09/21/2018] [Indexed: 01/03/2023] Open
Abstract
Expression of a heterologous xylose isomerase, deletion of the GRE3 aldose-reductase gene and overexpression of genes encoding xylulokinase (XKS1) and non-oxidative pentose-phosphate-pathway enzymes (RKI1, RPE1, TAL1, TKL1) enables aerobic growth of Saccharomyces cerevisiae on d-xylose. However, literature reports differ on whether anaerobic growth on d-xylose requires additional mutations. Here, CRISPR-Cas9-assisted reconstruction and physiological analysis confirmed an early report that this basic set of genetic modifications suffices to enable anaerobic growth on d-xylose in the CEN.PK genetic background. Strains that additionally carried overexpression cassettes for the transaldolase and transketolase paralogs NQM1 and TKL2 only exhibited anaerobic growth on d-xylose after a 7–10 day lag phase. This extended lag phase was eliminated by increasing inoculum concentrations from 0.02 to 0.2 g biomass L−1. Alternatively, a long lag phase could be prevented by sparging low-inoculum-density bioreactor cultures with a CO2/N2-mixture, thus mimicking initial CO2 concentrations in high-inoculum-density, nitrogen-sparged cultures, or by using l-aspartate instead of ammonium as nitrogen source. This study resolves apparent contradictions in the literature on the genetic interventions required for anaerobic growth of CEN.PK-derived strains on d-xylose. Additionally, it indicates the potential relevance of CO2 availability and anaplerotic carboxylation reactions for anaerobic growth of engineered S. cerevisiae strains on d-xylose.
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Affiliation(s)
- Jasmine M Bracher
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | | | - Wijb J C Dekker
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Maarten D Verhoeven
- DSM Biotechnology Centre, Alexander Fleminglaan 1, 2613 AX Delft, The Netherlands
| | - Antonius J A van Maris
- Department of Industrial Biotechnology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, AlbaNova University Center, SE 106 91, Stockholm, Sweden
| | - Jack T Pronk
- 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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Kwon DH, Park JB, Hong E, Ha SJ. Ethanol production from xylose is highly increased by the Kluyveromyces marxianus mutant 17694-DH1. Bioprocess Biosyst Eng 2018; 42:63-70. [DOI: 10.1007/s00449-018-2014-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 09/17/2018] [Indexed: 10/28/2022]
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11
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Hara KY, Kobayashi J, Yamada R, Sasaki D, Kuriya Y, Hirono-Hara Y, Ishii J, Araki M, Kondo A. Transporter engineering in biomass utilization by yeast. FEMS Yeast Res 2018; 17:4097189. [PMID: 28934416 DOI: 10.1093/femsyr/fox061] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 08/04/2017] [Indexed: 12/17/2022] Open
Abstract
Biomass resources are attractive carbon sources for bioproduction because of their sustainability. Many studies have been performed using biomass resources to produce sugars as carbon sources for cell factories. Expression of biomass hydrolyzing enzymes in cell factories is an important approach for constructing biomass-utilizing bioprocesses because external addition of these enzymes is expensive. In particular, yeasts have been extensively engineered to be cell factories that directly utilize biomass because of their manageable responses to many genetic engineering tools, such as gene expression, deletion and editing. Biomass utilizing bioprocesses have also been developed using these genetic engineering tools to construct metabolic pathways. However, sugar input and product output from these cells are critical factors for improving bioproduction along with biomass utilization and metabolic pathways. Transporters are key components for efficient input and output activities. In this review, we focus on transporter engineering in yeast to enhance bioproduction from biomass resources.
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Affiliation(s)
- Kiyotaka Y Hara
- Division of Environmental and Life Sciences, Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.,School of Food and Nutritional Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Jyumpei Kobayashi
- Graduate School of Science, Technology, and Innovation, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Ryosuke Yamada
- Department of Chemical Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan
| | - Daisuke Sasaki
- Graduate School of Science, Technology, and Innovation, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Yuki Kuriya
- Graduate School of Science, Technology, and Innovation, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Yoko Hirono-Hara
- School of Food and Nutritional Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Jun Ishii
- Graduate School of Science, Technology, and Innovation, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Michihiro Araki
- Graduate School of Science, Technology, and Innovation, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan.,Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Syogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Akihiko Kondo
- Graduate School of Science, Technology, and Innovation, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan.,Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
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12
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Pentjuss A, Stalidzans E, Liepins J, Kokina A, Martynova J, Zikmanis P, Mozga I, Scherbaka R, Hartman H, Poolman MG, Fell DA, Vigants A. Model-based biotechnological potential analysis of Kluyveromyces marxianus central metabolism. J Ind Microbiol Biotechnol 2017; 44:1177-1190. [PMID: 28444480 DOI: 10.1007/s10295-017-1946-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 04/16/2017] [Indexed: 12/11/2022]
Abstract
The non-conventional yeast Kluyveromyces marxianus is an emerging industrial producer for many biotechnological processes. Here, we show the application of a biomass-linked stoichiometric model of central metabolism that is experimentally validated, and mass and charge balanced for assessing the carbon conversion efficiency of wild type and modified K. marxianus. Pairs of substrates (lactose, glucose, inulin, xylose) and products (ethanol, acetate, lactate, glycerol, ethyl acetate, succinate, glutamate, phenylethanol and phenylalanine) are examined by various modelling and optimisation methods. Our model reveals the organism's potential for industrial application and metabolic engineering. Modelling results imply that the aeration regime can be used as a tool to optimise product yield and flux distribution in K. marxianus. Also rebalancing NADH and NADPH utilisation can be used to improve the efficiency of substrate conversion. Xylose is identified as a biotechnologically promising substrate for K. marxianus.
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Affiliation(s)
- A Pentjuss
- Institute of Microbiology and Biotechnology, University of Latvia, Jelgavas str. 1, Riga, 1004, Latvia
| | - E Stalidzans
- Institute of Microbiology and Biotechnology, University of Latvia, Jelgavas str. 1, Riga, 1004, Latvia.
| | - J Liepins
- Institute of Microbiology and Biotechnology, University of Latvia, Jelgavas str. 1, Riga, 1004, Latvia
| | - A Kokina
- Institute of Microbiology and Biotechnology, University of Latvia, Jelgavas str. 1, Riga, 1004, Latvia
| | - J Martynova
- Institute of Microbiology and Biotechnology, University of Latvia, Jelgavas str. 1, Riga, 1004, Latvia
| | - P Zikmanis
- Institute of Microbiology and Biotechnology, University of Latvia, Jelgavas str. 1, Riga, 1004, Latvia
| | - I Mozga
- Institute of Microbiology and Biotechnology, University of Latvia, Jelgavas str. 1, Riga, 1004, Latvia
| | - R Scherbaka
- Institute of Microbiology and Biotechnology, University of Latvia, Jelgavas str. 1, Riga, 1004, Latvia
| | - H Hartman
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, OX, OX3 0BP, UK
| | - M G Poolman
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, OX, OX3 0BP, UK
| | - D A Fell
- Department of Biological and Medical Sciences, Oxford Brookes University, Headington, OX, OX3 0BP, UK
| | - A Vigants
- Institute of Microbiology and Biotechnology, University of Latvia, Jelgavas str. 1, Riga, 1004, Latvia
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Nitiyon S, Keo-Oudone C, Murata M, Lertwattanasakul N, Limtong S, Kosaka T, Yamada M. Efficient conversion of xylose to ethanol by stress-tolerant Kluyveromyces marxianus BUNL-21. SPRINGERPLUS 2016; 5:185. [PMID: 27026881 PMCID: PMC4769242 DOI: 10.1186/s40064-016-1881-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 02/16/2016] [Indexed: 11/29/2022]
Abstract
The fermentation ability of thermotolerant Kluyveromyces marxianus BUNL-21 isolated in Laos was investigated. Comparison with thermotolerant K. marxianus DMKU3-1042 as one of the most thermotolerant yeasts isolated previously revealed that the strain possesses stronger ability for conversion of xylose to ethanol, resistance to 2-deoxyglucose in the case of pentose, and tolerance to various stresses including high temperature and hydrogen peroxide. K. marxianus BUNL-21 was found to have ethanol fermentation activity from xylose that is slightly lower and much higher than that of Scheffersomyces stipitis (Pichia stipitis) at 30 °C and at higher temperatures, respectively. The lower ethanol production seems to be due to large accumulation of acetic acid. The possible mechanism of acetic acid accumulation is discussed. In addition, it was found that both K. marxianus strains produced ethanol in the presence of 10 mM hydroxymethylfurfural or furfural, at a level almost equivalent to that in their absence. Therefore, K. marxianus BUNL-21 is a highly competent yeast for high-temperature ethanol fermentation with lignocellulosic biomass.
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Affiliation(s)
- Sukanya Nitiyon
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube, 755-8505 Japan
| | - Chansom Keo-Oudone
- Department of Biology, Faculty of Science, National University of Laos, Vientiane, Lao PDR
| | - Masayuki Murata
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube, 755-8505 Japan
| | - Noppon Lertwattanasakul
- Department of Microbiology, Faculty of Science, Kasetsart University, Bangkok, 10900 Thailand
| | - Savitree Limtong
- Department of Microbiology, Faculty of Science, Kasetsart University, Bangkok, 10900 Thailand
| | - Tomoyuki Kosaka
- Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, 753-8515 Japan
| | - Mamoru Yamada
- Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube, 755-8505 Japan ; Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, 753-8515 Japan
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Moysés DN, Reis VCB, de Almeida JRM, de Moraes LMP, Torres FAG. Xylose Fermentation by Saccharomyces cerevisiae: Challenges and Prospects. Int J Mol Sci 2016; 17:207. [PMID: 26927067 PMCID: PMC4813126 DOI: 10.3390/ijms17030207] [Citation(s) in RCA: 138] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 01/23/2016] [Accepted: 01/27/2016] [Indexed: 12/17/2022] Open
Abstract
Many years have passed since the first genetically modified Saccharomyces cerevisiae strains capable of fermenting xylose were obtained with the promise of an environmentally sustainable solution for the conversion of the abundant lignocellulosic biomass to ethanol. Several challenges emerged from these first experiences, most of them related to solving redox imbalances, discovering new pathways for xylose utilization, modulation of the expression of genes of the non-oxidative pentose phosphate pathway, and reduction of xylitol formation. Strategies on evolutionary engineering were used to improve fermentation kinetics, but the resulting strains were still far from industrial application. Lignocellulosic hydrolysates proved to have different inhibitors derived from lignin and sugar degradation, along with significant amounts of acetic acid, intrinsically related with biomass deconstruction. This, associated with pH, temperature, high ethanol, and other stress fluctuations presented on large scale fermentations led the search for yeasts with more robust backgrounds, like industrial strains, as engineering targets. Some promising yeasts were obtained both from studies of stress tolerance genes and adaptation on hydrolysates. Since fermentation times on mixed-substrate hydrolysates were still not cost-effective, the more selective search for new or engineered sugar transporters for xylose are still the focus of many recent studies. These challenges, as well as under-appreciated process strategies, will be discussed in this review.
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Affiliation(s)
- Danuza Nogueira Moysés
- Departamento de Biologia Celular, Universidade de Brasília, Brasília, DF 70910-900, Brazil.
- Petrobras Research and Development Center, Biotechnology Management, Rio de Janeiro, RJ 21941-915, Brazil.
| | | | - João Ricardo Moreira de Almeida
- Embrapa Agroenergia, Laboratório de Genética e Biotecnologia, Parque Estação Biológica s/n, Av. W3 Norte, Brasília, DF 70770-901, Brazil.
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Zhang B, Zhang J, Wang D, Gao X, Sun L, Hong J. Data for rapid ethanol production at elevated temperatures by engineered thermotolerant Kluyveromyces marxianus via the NADP(H)-preferring xylose reductase-xylitol dehydrogenase pathway. Data Brief 2015; 5:179-86. [PMID: 26543879 PMCID: PMC4589838 DOI: 10.1016/j.dib.2015.08.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 08/24/2015] [Accepted: 08/25/2015] [Indexed: 01/02/2023] Open
Abstract
A thermo-tolerant NADP(H)-preferring xylose pathway was constructed in Kluyveromyces marxianus for ethanol production with xylose at elevated temperatures (Zhang et al., 2015 [25]). Ethanol production yield and efficiency was enhanced by pathway engineering in the engineered strains. The constructed strain, YZJ088, has the ability to co-ferment glucose and xylose for ethanol and xylitol production, which is a critical step toward enabling economic biofuel production from lignocellulosic biomass. This study contains the fermentation results of strains using the metabolic pathway engineering procedure. The ethanol-producing abilities of various yeast strains under various conditions were compared, and strain YZJ088 showed the highest production and fastest productivity at elevated temperatures. The YZJ088 xylose fermentation results indicate that it fermented well with xylose at either low or high inoculum size. When fermented with an initial cell concentration of OD600=15 at 37 °C, YZJ088 consumed 200 g/L xylose and produced 60.07 g/L ethanol; when the initial cell concentration was OD600=1 at 37 °C, YZJ088 consumed 98.96 g/L xylose and produced 33.55 g/L ethanol with a productivity of 0.47 g/L/h. When fermented with 100 g/L xylose at 42 °C, YZJ088 produced 30.99 g/L ethanol with a productivity of 0.65 g/L/h, which was higher than that produced at 37 °C.
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Affiliation(s)
- Biao Zhang
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China
- Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China
| | - Jia Zhang
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China
- Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China
| | - Dongmei Wang
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China
- Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China
| | - Xiaolian Gao
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China
- Department of Biology and Biochemistry, University of Houston, Houston, TX 77004-5001, USA
- Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China
| | - Lianhong Sun
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China
- Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China
| | - Jiong Hong
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China
- Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui 230026, PR China
- Corresponding author at: School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, PR China. Tel.: +86 551 63600705; fax: +86 551 63601443.School of Life Science, University of Science and Technology of ChinaHefeiAnhui230027PR China
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Okamoto K, Uchii A, Kanawaku R, Yanase H. Bioconversion of xylose, hexoses and biomass to ethanol by a new isolate of the white rot basidiomycete Trametes versicolor. SPRINGERPLUS 2014; 3:121. [PMID: 24624317 PMCID: PMC3950376 DOI: 10.1186/2193-1801-3-121] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 02/20/2014] [Indexed: 11/17/2022]
Abstract
Second-generation bioethanol production requires the development of economically feasible and sustainable processes that use renewable lignocellulosic biomass as a starting material. However, the microbial fermentation of xylose, which is the principal pentose sugar in hemicellulose, is a limiting factor in developing such processes. Here, a strain of the white rot basidiomycete Trametes versicolor that was capable of efficiently fermenting xylose was newly isolated and characterized. This strain, designated KT9427, was capable of assimilating and converting xylose to ethanol under anaerobic conditions with a yield of 0.44 g ethanol per 1 g of sugar consumed. In culture medium containing low yeast extract concentrations, xylose consumption and ethanol productivity were enhanced. Adjusting the initial pH between 3.0 and 5.0 did not markedly influence xylose fermentation. T. versicolor KT9427 also produced ethanol from glucose, mannose, fructose, cellobiose and maltose at yields ranging from 0.45 to 0.49 g ethanol per 1 g of sugar consumed. In addition, strain KT9427 exhibited favourable conversion of non-pretreated starch, cellulose, xylan, wheat bran and rice straw into ethanol compared to common recombinant yeast strains. Taken together, the present findings suggest that T. versicolor KT9427 is a promising candidate for environmentally friendly ethanol production directly from lignocellulosic biomass.
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Affiliation(s)
- Kenji Okamoto
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama, Tottori, 680-8552 Japan
| | - Atsushi Uchii
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama, Tottori, 680-8552 Japan
| | - Ryuichi Kanawaku
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama, Tottori, 680-8552 Japan
| | - Hideshi Yanase
- Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama, Tottori, 680-8552 Japan
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17
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Lulu L, Ling Z, Dongmei W, Xiaolian G, Hisanori T, Hidehiko K, Jiong H. Identification of a xylitol dehydrogenase gene from Kluyveromyces marxianus NBRC1777. Mol Biotechnol 2013; 53:159-69. [PMID: 22351371 DOI: 10.1007/s12033-012-9508-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Xylitol dehydrogenase (XDH) (EC 1.1.1.9) is one of the key enzymes in the xylose fermentation pathway in yeast and fungi. A xylitol dehydrogenase gene (XYL2) encoding a XDH was cloned from Kluyveromyces marxianus NBRC 1777, and the in vivo function was validated by disruption and complementation analysis. The highest activity of KmXDH could be observed at pH 9.5 during 55°C. The values of k(cat)/K(m) indicate that KmXDH prefers NAD(+) to NADP(+) (k(cat)/K(m NAD)(+) 3681/min mM and k(cat)/K(m NADP)(+) 1361/min mM). The different coenzyme preference between KmXR and KmXDH caused an accumulation of NADH in the xylose utilization pathway. The redox imbalance may be one of the reasons to cause the poor xylose fermentation under oxygen-limited conditions in K. marxianus NBRC1777.
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Affiliation(s)
- Li Lulu
- School of Life Science, University of Science and Technology of China, Hefei, 230027 Anhui, People's Republic of China
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18
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19
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Improved xylose fermentation of Kluyveromyces marxianus at elevated temperature through construction of a xylose isomerase pathway. ACTA ACUST UNITED AC 2013; 40:841-54. [DOI: 10.1007/s10295-013-1282-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 04/26/2013] [Indexed: 10/26/2022]
Abstract
Abstract
To improve the xylose fermentation ability of Kluyveromyces marxianus, a xylose assimilation pathway through xylose isomerase was constructed. The genes encoding xylose reductase (KmXyl1) and xylitol dehydrogenase (KmXyl2) were disrupted in K. marxianus YHJ010 and the resultant strain was named YRL002. A codon-optimized xylose isomerase gene from Orpinomyces was transformed into K. marxianus YRL002 and expressed under GAPDH promoter. The transformant was adapted in the SD medium containing 1 % casamino acid with 2 % xylose as sole carbon source. After 32 times of trans-inoculation, a strain named YRL005, which can grow at a specific growth rate of 0.137/h with xylose as carbon source, was obtained. K. marxianus YRL005 could ferment 30.15 g/l of xylose and produce 11.52 g/l ethanol with a yield of 0.38 g/g, production rate of 0.069 g/l/h at 42 °C, and also could ferment 16.60 g/l xylose to produce 5.21 g/l ethanol with a yield of 0.31 g/g, and production rate of 0.054 g/l h at 45 °C. Co-fermentation with 2 % glucose could not improve the amount and yield of ethanol fermented from xylose obviously, but it could improve the production rate. Furthermore, K. marxianus YRL005 can ferment with the corn cob hydrolysate, which contained 20.04 g/l xylose to produce 8.25 g/l ethanol. It is a good platform to construct thermo-tolerant xylose fermentation yeast.
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20
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Improving ethanol and xylitol fermentation at elevated temperature through substitution of xylose reductase in Kluyveromyces marxianus. J Ind Microbiol Biotechnol 2013; 40:305-16. [PMID: 23392758 DOI: 10.1007/s10295-013-1230-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2012] [Accepted: 01/09/2013] [Indexed: 10/27/2022]
Abstract
Thermo-tolerant yeast Kluyveromyces marxianus is able to utilize a wide range of substrates, including xylose; however, the xylose fermentation ability is weak because of the redox imbalance under oxygen-limited conditions. Alleviating the intracellular redox imbalance through engineering the coenzyme specificity of NADPH-preferring xylose reductase (XR) and improving the expression of XR should promote xylose consumption and fermentation. In this study, the native xylose reductase gene (Kmxyl1) of the K. marxianus strain was substituted with XR or its mutant genes from Pichia stipitis (Scheffersomyces stipitis). The ability of the resultant recombinant strains to assimilate xylose to produce xylitol and ethanol at elevated temperature was greatly improved. The strain YZB014 expressing mutant PsXR N272D, which has a higher activity with both NADPH and NADH as the coenzyme, achieved the best results, and produced 3.55 g l(-1) ethanol and 11.32 g l(-1) xylitol-an increase of 12.24- and 2.70-fold in product at 42 °C, respectively. A 3.94-fold increase of xylose consumption was observed compared with the K. marxianus YHJ010 harboring KmXyl1. However, the strain YZB015 expressing a mutant PsXR K21A/N272D, with which co-enzyme preference was completely reversed from NADPH to NADH, failed to ferment due to the low expression. So in order to improve xylose consumption and fermentation in K. marxianus, both higher activity and co-enzyme specificity change are necessary.
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21
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Jeffries TW, Fady JH, Lightfoot EN. Effect of glucose supplements on the fermentation of xylose by Pachysolen tannophilus. Biotechnol Bioeng 2012; 27:171-6. [PMID: 18553652 DOI: 10.1002/bit.260270211] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Hemicellulosic sugars, predominantly D-xylose, comprise about one-half the total carbohydrate that can be obtained from hardwoods and agricultural residues through dilute acid hydrolysis. Because rates and yields in the xylose fermentation are low, economic utilization of these materials as fermentation feedstocks is difficult. Pachysolen tannophilus formed 5.5% ethanol from 12% glucose but only 2% ethanol from 12% xylcose. Aeration doubled the specific rate of D-glucose fermentation by P. tannophilus, as compared to anaerobic fermentation, but the specific rate of the xylose fermentation remained unchanged. Periodic additions of 0.5% D-glucose to aerobic fermentations of 3% xylose increased the yield of ethanol from 0.28 g/g xylose to greater than 0.41 g/g xylose utilized. The rate of xylose utilization remained unchanged, and radiotracer studies showed that addition of 0.5% glucose did not inhibit xylose utilization under aerobic or anaerobic conditions. No enhancement was observed anaerobically, nor was enhancement observed with acid hydrolysates, apparently because of the presence of acetic acid which inhibited growth and fermentation.
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Affiliation(s)
- T W Jeffries
- United States Department of Agriculture, Forest Service, Forest Products Laboratory, Madison, Wisconsin 53705
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22
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Efficient xylose fermentation by the brown rot fungus Neolentinus lepideus. Enzyme Microb Technol 2012; 50:96-100. [DOI: 10.1016/j.enzmictec.2011.10.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 10/06/2011] [Accepted: 10/12/2011] [Indexed: 11/22/2022]
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23
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Zhang B, Zhang L, Wang D, Gao X, Hong J. Identification of a xylose reductase gene in the xylose metabolic pathway of Kluyveromyces marxianus NBRC1777. J Ind Microbiol Biotechnol 2011; 38:2001-10. [PMID: 21643709 DOI: 10.1007/s10295-011-0990-z] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Accepted: 05/11/2011] [Indexed: 11/28/2022]
Abstract
Kluyveromyces marxianus is thermotolerant yeast that is able to utilize a wider range of substrates and has greater thermal tolerance than most other yeast species. K. marxianus can assimilate xylose, but its ability to produce ethanol from xylose in oxygen-limited environments is poor. In the present study, the K. marxianus xylose reductase (KmXR) gene (Kmxyl1) was cloned and the recombinant enzyme was characterized to clarify the factors that limit xylose fermentation in K. marxianus NBRC1777. KmXR is a key enzyme in the xylose metabolism of K. marxianus, which was verified by disruption of the Kmxyl1 gene. The Km of the recombinant KmXR for NADPH is 65.67 μM and KmXR activity is 1.295 U/mg, which is lower than those of most reported yeast XRs, and the enzyme has no activity with coenzyme NADH. This result demonstrates that the XR from K. marxianus is highly coenzyme specific; combined with the extremely low XDH activity of K. marxianus with NADP+, the limitation of xylose fermentation is due to a redox imbalance under anaerobic conditions and low KmXR activity.
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Affiliation(s)
- Biao Zhang
- School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, People's Republic of China
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24
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Identification of a xylulokinase catalyzing xylulose phosphorylation in the xylose metabolic pathway of Kluyveromyces marxianus NBRC1777. J Ind Microbiol Biotechnol 2011; 38:1739-46. [PMID: 21451977 DOI: 10.1007/s10295-011-0963-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2011] [Accepted: 03/12/2011] [Indexed: 10/24/2022]
Abstract
Xylulokinase is one of the key enzymes in xylose metabolism and fermentation, and fine-tuned expression of xylulokinase can improve xylose fermentation in yeast. To improve the efficiency of xylose fermentation in Kluyveromyces marxianus, the gene KmXYL3, which encodes a D: -xylulokinase (E.C. 2.7.1.17), was isolated from K. marxianus NBRC1777. KmXYL3 was expressed in Escherichia coli BL21 (DE3) cells, and the specific activity of the resulting recombinant purified xylulokinase was 23.5 mU/mg. Disruption of KmXYL3 resulted in both loss of xylitol utilization and marked decrease in xylose utilization, proving that KmXYL3 encodes a xylulokinase that catalyzes the reaction from xylulose to xylulose 5-phosphate in the xylose metabolic pathway. The slow assimilation of xylose observed in the KmXYL3-disrupted strain indicates that KmXYL3 is critical for xylose and xylitol utilization; however, K. marxianus utilizes a bypass pathway for xylose assimilation, and this pathway does not involve xylitol or xylulose.
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25
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Rocha MVP, Rodrigues THS, Melo VMM, Gonçalves LRB, Macedo GRD. Cashew apple bagasse as a source of sugars for ethanol production by Kluyveromyces marxianus CE025. J Ind Microbiol Biotechnol 2010; 38:1099-107. [DOI: 10.1007/s10295-010-0889-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Accepted: 10/03/2010] [Indexed: 10/18/2022]
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26
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Delgenes JP, Moletta R, Navarro JM. Fermentation of D-xylose, D-glucose, L-arabinose mixture by Pichia stipitis: Effect of the oxygen transfer rate on fermentation performance. Biotechnol Bioeng 2010; 34:398-402. [PMID: 18588117 DOI: 10.1002/bit.260340314] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- J P Delgenes
- Institut National de la Recherche Agronomique, Station d'Oenologie et de Technologie des Produits Végétaux, Boulevard du Général de Gaulle 11104 Narbonne Cedex France
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27
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la Grange DC, den Haan R, van Zyl WH. Engineering cellulolytic ability into bioprocessing organisms. Appl Microbiol Biotechnol 2010; 87:1195-208. [DOI: 10.1007/s00253-010-2660-x] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 05/02/2010] [Accepted: 05/02/2010] [Indexed: 10/19/2022]
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28
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Nonklang S, Abdel-Banat BMA, Cha-aim K, Moonjai N, Hoshida H, Limtong S, Yamada M, Akada R. High-temperature ethanol fermentation and transformation with linear DNA in the thermotolerant yeast Kluyveromyces marxianus DMKU3-1042. Appl Environ Microbiol 2008; 74:7514-21. [PMID: 18931291 PMCID: PMC2607150 DOI: 10.1128/aem.01854-08] [Citation(s) in RCA: 159] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Accepted: 10/13/2008] [Indexed: 11/20/2022] Open
Abstract
We demonstrate herein the ability of Kluyveromyces marxianus to be an efficient ethanol producer and host for expressing heterologous proteins as an alternative to Saccharomyces cerevisiae. Growth and ethanol production by strains of K. marxianus and S. cerevisiae were compared under the same conditions. K. marxianus DMKU3-1042 was found to be the most suitable strain for high-temperature growth and ethanol production at 45 degrees C. This strain, but not S. cerevisiae, utilized cellobiose, xylose, xylitol, arabinose, glycerol, and lactose. To develop a K. marxianus DMKU3-1042 derivative strain suitable for genetic engineering, a uracil auxotroph was isolated and transformed with a linear DNA of the S. cerevisiae ScURA3 gene. Surprisingly, Ura(+) transformants were easily obtained. By Southern blot hybridization, the linear ScURA3 DNA was found to have inserted randomly into the K. marxianus genome. Sequencing of one Lys(-) transformant confirmed the disruption of the KmLYS1 gene by the ScURA3 insertion. A PCR-amplified linear DNA lacking K. marxianus sequences but containing an Aspergillus alpha-amylase gene under the control of the ScTDH3 promoter together with an ScURA3 marker was subsequently used to transform K. marxianus DMKU3-1042 in order to obtain transformants expressing Aspergillus alpha-amylase. Our results demonstrate that K. marxianus DMKU3-1042 can be an alternative cost-effective bioethanol producer and a host for transformation with linear DNA by use of S. cerevisiae-based molecular genetic tools.
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Affiliation(s)
- Sanom Nonklang
- Department of Applied Molecular Bioscience, Yamaguchi University Graduate School of Medicine, Tokiwadai, Ube 755-8611, Japan
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Margaritis A, Merchant FJA, Abbott BJ. Advances in Ethanol Production using Immobilized Cell Systems. Crit Rev Biotechnol 2008. [DOI: 10.3109/07388558309084660] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Lovitt RW, Kim BH, Shen GJ, Zeikus JG, Phillips JA. Solvent Production by Microorganisms. Crit Rev Biotechnol 2008. [DOI: 10.3109/07388558809150725] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Fonseca GG, Heinzle E, Wittmann C, Gombert AK. The yeast Kluyveromyces marxianus and its biotechnological potential. Appl Microbiol Biotechnol 2008; 79:339-54. [PMID: 18427804 DOI: 10.1007/s00253-008-1458-6] [Citation(s) in RCA: 307] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Revised: 03/12/2008] [Accepted: 03/13/2008] [Indexed: 11/26/2022]
Abstract
Strains belonging to the yeast species Kluyveromyces marxianus have been isolated from a great variety of habitats, which results in a high metabolic diversity and a substantial degree of intraspecific polymorphism. As a consequence, several different biotechnological applications have been investigated with this yeast: production of enzymes (beta-galactosidase, beta-glucosidase, inulinase, and polygalacturonases, among others), of single-cell protein, of aroma compounds, and of ethanol (including high-temperature and simultaneous saccharification-fermentation processes); reduction of lactose content in food products; production of bioingredients from cheese-whey; bioremediation; as an anticholesterolemic agent; and as a host for heterologous protein production. Compared to its congener and model organism, Kluyveromyces lactis, the accumulated knowledge on K. marxianus is much smaller and spread over a number of different strains. Although there is no publicly available genome sequence for this species, 20% of the CBS 712 strain genome was randomly sequenced (Llorente et al. in FEBS Lett 487:71-75, 2000). In spite of these facts, K. marxianus can envisage a great biotechnological future because of some of its qualities, such as a broad substrate spectrum, thermotolerance, high growth rates, and less tendency to ferment when exposed to sugar excess, when compared to K. lactis. To increase our knowledge on the biology of this species and to enable the potential applications to be converted into industrial practice, a more systematic approach, including the careful choice of (a) reference strain(s) by the scientific community, would certainly be of great value.
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32
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Schwan RF, Rose A. Polygalacturonase production byKluyveromyces marxianus:effect of medium composition. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1365-2672.1994.tb04416.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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33
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Sarrouh B, Silva S, Santos D, Converti A. Technical/Economical Evaluation of Sugarcane Bagasse Hydrolysis for Bioethanol Production. Chem Eng Technol 2007. [DOI: 10.1002/ceat.200600271] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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34
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Magee RJ, Kosaric N. Bioconversion of hemicellulosics. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2005; 32:61-93. [PMID: 2932894 DOI: 10.1007/bfb0009525] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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35
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Olsson L, Hahn-Hägerdal B. Fermentation of lignocellulosic hydrolysates for ethanol production. Enzyme Microb Technol 1996. [DOI: 10.1016/0141-0229(95)00157-3] [Citation(s) in RCA: 498] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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36
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37
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Affiliation(s)
- P Mishra
- Biochemical Engineering Research Centre, Indian Institute of Technology, New Delhi
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38
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Purification and properties of xylitol dehydrogenase from the xylose-fermenting yeastCandida shehatae. Appl Biochem Biotechnol 1990. [DOI: 10.1007/bf02921534] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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39
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Webb SR, Lee H. Regulation of d-xylose utilization by hexoses in pentose-fermenting yeasts. Biotechnol Adv 1990; 8:685-97. [PMID: 14543690 DOI: 10.1016/0734-9750(90)91991-o] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aldopentose D-xylose is one of the most abundant sugars in plant biomass and its efficient microbial utilization is of fundamental importance in the overall bioconversion of lignocellulosic materials into liquid fuels and chemicals. The discovery of pentose-fermenting yeasts in the early 1980's led to world wide interest because of the perceived potential for improved D-xylose fermentation to enhance the prospect of biomass conversions. However, the utilization of D-xylose by pentose-fermenting yeasts can be adversely affected by the hexoses, mainly D-glucose and D-mannose, which are usually present in high amounts in lignocellulosic hydrolysates. Research in the past several years has uncovered some of the regulatory effects of D-glucose on D-xylose utilization. However, much remains unknown about the mechanisms responsible for these effects. This review summarizes the current state of knowledge on the induction, repression and inactivation of D-xylose utilization in pentose-fermenting yeasts.
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Affiliation(s)
- S R Webb
- Department of Environmental Biology, University of Guelph, Ontario, Canada
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40
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Evaluation of xylose-fermenting yeasts for ethanol production from spent sulfite liquor. Enzyme Microb Technol 1989. [DOI: 10.1016/0141-0229(89)90099-9] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Abstract
Fermentation of D-xylose is of interest in enhancing the yield of ethanol obtainable from lignocellulosic hydrolysates. Such hydrolysates can contain both pentoses and hexoses, and while technology to convert hexoses to ethanol is well established, the fermentation of pentoses had been problematical. To overcome the difficulty, yeasts and fungi have been sought and identified in recent years that can convert D-xylose into ethanol. However, operation of their cultures in the presence of the pentose to obtain rapid and efficient ethanol production is somewhat more complex than in the archetype alcoholic fermentation, Saccharomyces cerevisiae on D-glucose. The complexity stems, in part, from the association of ethanol accumulation in cultures where D-xylose is the sole carbon source with conditions that limit growth, by oxygen in particular, although limitation by other nutrients might also be implicated. Aspects of screening for appropriate organisms and of the parameters that play a role in determining culture variables, especially those associated with ethanol productivity, are reviewed. Performance with D-xylose as sole carbon source, in sugar mixtures, and in lignocellulosic hydrolysates is discussed. A model that involves biochemical considerations of D-xylose metabolism is presented that rationalizes the effects of oxygen on cultures where D-xylose is the sole carbon source, notably effects of the specific rate of oxygen use on the rate and extent of ethanol accumulation. Alternate methods to direct fermentation of D-xylose have been developed that depend on its prior isomerization to D-xylose, followed by fermentation of the pentulose by certain yeasts and fungi. Factors involved in the biochemistry, use, and performance of these methods, which with some organisms involves sensitivity to oxygen, are reviewed.
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Affiliation(s)
- H Schneider
- Division of Biological Sciences, National Research Council of Canada, Ottawa, Ontario
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43
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Delgenes JP, Moletta R, Navarro JM. Fermentation ofd-xylose,d-glucose andl-arabinose mixture byPichia stipitis Y 7124: sugar tolerance. Appl Microbiol Biotechnol 1988. [DOI: 10.1007/bf01982895] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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44
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Delgenes JP, Moletta R, Navarro JM. Fermentation of d-xylose, d-glucose and l-arabinose mixture by Pichia stipitis Y 7124: sugar tolerance. Appl Microbiol Biotechnol 1988. [DOI: 10.1007/bf00251695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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45
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Ethanol production from xylose by Thermoanaerobacter ethanolicus in batch and continuous culture. Arch Microbiol 1988. [DOI: 10.1007/bf00409717] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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46
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The ethanol tolerance of Pichia stipitis Y 7124 grown on a d-xylose, d-glucose and l-arabinose mixture. ACTA ACUST UNITED AC 1988. [DOI: 10.1016/0385-6380(88)90008-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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47
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Bicho PA, Runnals PL, Cunningham JD, Lee H. Induction of Xylose Reductase and Xylitol Dehydrogenase Activities in
Pachysolen tannophilus
and
Pichia stipitis
on Mixed Sugars. Appl Environ Microbiol 1988; 54:50-54. [PMID: 16347538 PMCID: PMC202395 DOI: 10.1128/aem.54.1.50-54.1988] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The induction of xylose reductase and xylitol dehydrogenase activities on mixed sugars was investigated in the yeasts
Pachysolen tannophilus
and
Pichia stipitis
. Enzyme activities induced on
d
-xylose served as the controls. In both yeasts,
d
-glucose,
d
-mannose, and 2-deoxyglucose inhibited enzyme induction by
d
-xylose to various degrees. Cellobiose,
l
-arabinose, and
d
-galactose were not inhibitory. In liquid batch culture,
P. tannophilus
utilized
d
-glucose and
d
-mannose rapidly and preferentially over
d
-xylose, while
d
-galactose consumption was poor and lagged behind that of the pentose sugar. In
P. stipitis
, all three hexoses were used preferentially over
d
-xylose. The results showed that the repressibility of xylose reductase and xylitol dehydrogenase may limit the potential of yeast fermentation of pentose sugars in hydrolysates of lignocellulosic substrates.
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Affiliation(s)
- Paul A Bicho
- Department of Environmental Biology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
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48
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Pachysolen tannophilus: Properties and process considerations for ethanol production from d-xylose. Enzyme Microb Technol 1987. [DOI: 10.1016/0141-0229(87)90043-3] [Citation(s) in RCA: 118] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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49
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Delgenes JP, Moletta R, Navarro JM. The effect of aeration on D-xylose fermentation byPachysolen tannophilus,Pichia stipitis,Kluyveromyces marxianus andCandida shehatae. Biotechnol Lett 1986. [DOI: 10.1007/bf01078656] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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50
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Bolen PL, Roth KA, Freer SN. Affinity Purifications of Aldose Reductase and Xylitol Dehydrogenase from the Xylose-Fermenting Yeast
Pachysolen tannophilus. Appl Environ Microbiol 1986; 52:660-4. [PMID: 16347161 PMCID: PMC239093 DOI: 10.1128/aem.52.4.660-664.1986] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although xylose is a major product of hydrolysis of lignocellulosic materials, few yeasts are able to convert it to ethanol. In
Pachysolen tannophilus
, one of the few xylose-fermenting yeasts found, aldose reductase and xylitol dehydrogenase were found to be key enzymes in the metabolic pathway for xylose fermentation. This paper presents a method for the rapid and simultaneous purification of both aldose reductase and xylitol dehydrogenase from
P. tannophilus.
Preliminary studies indicate that this method may be easily adapted to purify similar enzymes from other xylose-fermenting yeasts.
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Affiliation(s)
- P L Bolen
- Northern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Peoria, Illinois 61604
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