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Das S, Chandukishore T, Ulaganathan N, Dhodduraj K, Gorantla SS, Chandna T, Gupta LK, Sahoo A, Atheena PV, Raval R, Anjana PA, DasuVeeranki V, Prabhu AA. Sustainable biorefinery approach by utilizing xylose fraction of lignocellulosic biomass. Int J Biol Macromol 2024; 266:131290. [PMID: 38569993 DOI: 10.1016/j.ijbiomac.2024.131290] [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: 11/03/2023] [Revised: 03/20/2024] [Accepted: 03/29/2024] [Indexed: 04/05/2024]
Abstract
Lignocellulosic biomass (LCB) has been a lucrative feedstock for developing biochemical products due to its rich organic content, low carbon footprint and abundant accessibility. The recalcitrant nature of this feedstock is a foremost bottleneck. It needs suitable pretreatment techniques to achieve a high yield of sugar fractions such as glucose and xylose with low inhibitory components. Cellulosic sugars are commonly used for the bio-manufacturing process, and the xylose sugar, which is predominant in the hemicellulosic fraction, is rejected as most cell factories lack the five‑carbon metabolic pathways. In the present review, more emphasis was placed on the efficient pretreatment techniques developed for disintegrating LCB and enhancing xylose sugars. Further, the transformation of the xylose to value-added products through chemo-catalytic routes was highlighted. In addition, the review also recapitulates the sustainable production of biochemicals by native xylose assimilating microbes and engineering the metabolic pathway to ameliorate biomanufacturing using xylose as the sole carbon source. Overall, this review will give an edge on the bioprocessing of microbial metabolism for the efficient utilization of xylose in the LCB.
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Affiliation(s)
- Satwika Das
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - T Chandukishore
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Nivedhitha Ulaganathan
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Kawinharsun Dhodduraj
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Sai Susmita Gorantla
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Teena Chandna
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Laxmi Kumari Gupta
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Ansuman Sahoo
- Biochemical Engineering Laboratory, Department of Bioscience and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - P V Atheena
- Department of Biotechnology, Manipal Institute of Technology, Manipal 576104, Karnataka, India
| | - Ritu Raval
- Department of Biotechnology, Manipal Institute of Technology, Manipal 576104, Karnataka, India
| | - P A Anjana
- Department of Chemical Engineering, National Institute of Technology Warangal, Warangal 506004, Telangana, India
| | - Venkata DasuVeeranki
- Biochemical Engineering Laboratory, Department of Bioscience and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Ashish A Prabhu
- Bioprocess Development Research Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal 506004, Telangana, India.
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Li LX, Yu LY, Wang B, Pan L. Impact of overexpressing NADH kinase on glucoamylase production in Aspergillus niger. J Ind Microbiol Biotechnol 2022; 49:6602362. [PMID: 35665816 PMCID: PMC9338884 DOI: 10.1093/jimb/kuac015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 05/21/2022] [Indexed: 11/13/2022]
Abstract
Glucoamylase has a wide range of applications in the production of glucose, antibiotics, amino acids, and other fermentation industries. Fungal glucoamylase, in particular, has attracted much attention because of its wide application in different industries, among which Aspergillus niger is the most popular strain producing glucoamylase. The low availability of NADPH was found to be one of the limiting factors for the overproduction of glucoamylase. In this study, 3 NADH kinases (AN03, AN14, and AN17) and malic enzyme (maeA) were overexpressed in aconidial A. niger by CRISPR/Cas9 technology, significantly increasing the size of the NADPH pool, resulting in the activity of glucoamylase was improved by about 70%, 50%, 90%, and 70%, respectively; the total secreted protein was increased by about 25%, 22%, 52%, and 26%, respectively. Furthermore, the combination of the mitochondrial NADH kinase (AN17) and the malic enzyme (maeA) increased glucoamylase activity by a further 19%. This study provided an effective strategy for enhancing glucoamylase production of A. niger.
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Affiliation(s)
- Lin-Xiang Li
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou 510006, Guangdong, China.,Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Le-Yi Yu
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou 510006, Guangdong, China.,Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Bin Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou 510006, Guangdong, China.,Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Li Pan
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou 510006, Guangdong, China.,Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
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3
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Sharma J, Kumar V, Prasad R, Gaur NA. Engineering of Saccharomyces cerevisiae as a consolidated bioprocessing host to produce cellulosic ethanol: Recent advancements and current challenges. Biotechnol Adv 2022; 56:107925. [DOI: 10.1016/j.biotechadv.2022.107925] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 01/24/2022] [Accepted: 02/06/2022] [Indexed: 01/01/2023]
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Narisetty V, Cox R, Bommareddy R, Agrawal D, Ahmad E, Pant KK, Chandel AK, Bhatia SK, Kumar D, Binod P, Gupta VK, Kumar V. Valorisation of xylose to renewable fuels and chemicals, an essential step in augmenting the commercial viability of lignocellulosic biorefineries. SUSTAINABLE ENERGY & FUELS 2021; 6:29-65. [PMID: 35028420 PMCID: PMC8691124 DOI: 10.1039/d1se00927c] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 10/25/2021] [Indexed: 05/30/2023]
Abstract
Biologists and engineers are making tremendous efforts in contributing to a sustainable and green society. To that end, there is growing interest in waste management and valorisation. Lignocellulosic biomass (LCB) is the most abundant material on the earth and an inevitable waste predominantly originating from agricultural residues, forest biomass and municipal solid waste streams. LCB serves as the renewable feedstock for clean and sustainable processes and products with low carbon emission. Cellulose and hemicellulose constitute the polymeric structure of LCB, which on depolymerisation liberates oligomeric or monomeric glucose and xylose, respectively. The preferential utilization of glucose and/or absence of the xylose metabolic pathway in microbial systems cause xylose valorization to be alienated and abandoned, a major bottleneck in the commercial viability of LCB-based biorefineries. Xylose is the second most abundant sugar in LCB, but a non-conventional industrial substrate unlike glucose. The current review seeks to summarize the recent developments in the biological conversion of xylose into a myriad of sustainable products and associated challenges. The review discusses the microbiology, genetics, and biochemistry of xylose metabolism with hurdles requiring debottlenecking for efficient xylose assimilation. It further describes the product formation by microbial cell factories which can assimilate xylose naturally and rewiring of metabolic networks to ameliorate xylose-based bioproduction in native as well as non-native strains. The review also includes a case study that provides an argument on a suitable pathway for optimal cell growth and succinic acid (SA) production from xylose through elementary flux mode analysis. Finally, a product portfolio from xylose bioconversion has been evaluated along with significant developments made through enzyme, metabolic and process engineering approaches, to maximize the product titers and yield, eventually empowering LCB-based biorefineries. Towards the end, the review is wrapped up with current challenges, concluding remarks, and prospects with an argument for intense future research into xylose-based biorefineries.
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Affiliation(s)
- Vivek Narisetty
- School of Water, Energy and Environment, Cranfield University Cranfield MK43 0AL UK +44 (0)1234754786
| | - Rylan Cox
- School of Water, Energy and Environment, Cranfield University Cranfield MK43 0AL UK +44 (0)1234754786
- School of Aerospace, Transport and Manufacturing, Cranfield University Cranfield MK43 0AL UK
| | - Rajesh Bommareddy
- Department of Applied Sciences, Northumbria University Newcastle upon Tyne NE1 8ST UK
| | - Deepti Agrawal
- Biochemistry and Biotechnology Area, Material Resource Efficiency Division, CSIR- Indian Institute of Petroleum Mohkampur Dehradun 248005 India
| | - Ejaz Ahmad
- Department of Chemical Engineering, Indian Institute of Technology (ISM) Dhanbad 826004 India
| | - Kamal Kumar Pant
- Department of Chemical Engineering, Indian Institute of Technology Delhi New Delhi 110016 India
| | - Anuj Kumar Chandel
- Department of Biotechnology, Engineering School of Lorena (EEL), University of São Paulo Lorena 12.602.810 Brazil
| | - Shashi Kant Bhatia
- Department of Biological Engineering, College of Engineering, Konkuk University Seoul 05029 Republic of Korea
| | - Dinesh Kumar
- School of Bioengineering & Food Technology, Shoolini University of Biotechnology and Management Sciences Solan 173229 Himachal Pradesh India
| | - Parmeswaran Binod
- Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST) Thiruvananthapuram 695 019 Kerala India
| | | | - Vinod Kumar
- School of Water, Energy and Environment, Cranfield University Cranfield MK43 0AL UK +44 (0)1234754786
- Department of Chemical Engineering, Indian Institute of Technology Delhi New Delhi 110016 India
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Yukawa T, Bamba T, Guirimand G, Matsuda M, Hasunuma T, Kondo A. Optimization of 1,2,4-butanetriol production from xylose in Saccharomyces cerevisiae by metabolic engineering of NADH/NADPH balance. Biotechnol Bioeng 2020; 118:175-185. [PMID: 32902873 DOI: 10.1002/bit.27560] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 08/09/2020] [Accepted: 08/27/2020] [Indexed: 01/02/2023]
Abstract
1,2,4-Butanetriol (BT) is used as a precursor for the synthesis of various pharmaceuticals and the energetic plasticizer 1,2,4-butanetriol trinitrate. In Saccharomyces cerevisiae, BT is biosynthesized from xylose via heterologous four enzymatic reactions catalyzed by xylose dehydrogenase, xylonate dehydratase, 2-ketoacid decarboxylase, and alcohol dehydrogenase. We here aimed to improve the BT yield in S. cerevisiae by genetic engineering. First, the amount of the key intermediate 2-keto-3-deoxy-xylonate as described previously was successfully reduced in 41% by multiple integrations of Lactococcus lactis 2-ketoacid decarboxylase gene kdcA into the yeast genome. Since the heterologous BT synthetic pathway is independent of yeast native metabolism, this manipulation has led to NADH/NADPH imbalance and deficiency during BT production. Overexpression of the NADH kinase POS5Δ17 lacking the mitochondrial targeting sequence to relieve NADH/NADPH imbalance resulted in the BT titer of 2.2 g/L (31% molar yield). Feeding low concentrations of glucose and xylose to support the supply of NADH resulted in BT titer of 6.6 g/L with (57% molar yield). Collectively, improving the NADH/NADPH ratio and supply from glucose are essential for the construction of a xylose pathway, such as the BT synthetic pathway, independent of native yeast metabolism.
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Affiliation(s)
- Takahiro Yukawa
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Takahiro Bamba
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan
| | - Gregory Guirimand
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan.,Biomolécules et Biotechnologies Végétales, EA 2106, Département of Agronomie, productions animale et végétale et agro-alimentaire, Université de Tours, Tours, France.,LE STUDIUM, Loire Valley Institute for Advanced Studies, Orléans, France
| | - Mami Matsuda
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan.,Engineering Biology Research Center, Kobe University, Kobe, Japan
| | - Tomohisa Hasunuma
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan.,Engineering Biology Research Center, Kobe University, Kobe, Japan
| | - Akihiko Kondo
- Graduate School of Science, Technology and Innovation, Kobe University, Kobe, Japan.,Engineering Biology Research Center, Kobe University, Kobe, Japan.,Biomass Engineering Program, RIKEN, Yokohama, Kanagawa, Japan
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6
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Tomàs-Gamisans M, Andrade CCP, Maresca F, Monforte S, Ferrer P, Albiol J. Redox Engineering by Ectopic Overexpression of NADH Kinase in Recombinant Pichia pastoris ( Komagataella phaffii): Impact on Cell Physiology and Recombinant Production of Secreted Proteins. Appl Environ Microbiol 2020; 86:e02038-19. [PMID: 31757828 PMCID: PMC7054088 DOI: 10.1128/aem.02038-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 11/16/2019] [Indexed: 11/20/2022] Open
Abstract
High-level expression and secretion of heterologous proteins in yeast cause an increased energy demand, which may result in altered metabolic flux distributions. Moreover, recombinant protein overproduction often results in endoplasmic reticulum (ER) stress and oxidative stress, causing deviations from the optimal NAD(P)H regeneration balance. In this context, overexpression of genes encoding enzymes catalyzing endogenous NADPH-producing reactions, such as the oxidative branch of the pentose phosphate pathway, has been previously shown to improve protein production in Pichia pastoris (syn. Komagataella spp.). In this study, we evaluate the overexpression of the Saccharomyces cerevisiaePOS5-encoded NADH kinase in a recombinant P. pastoris strain as an alternative approach to overcome such redox constraints. Specifically, POS5 was cooverexpressed in a strain secreting an antibody fragment, either by directing Pos5 to the cytosol or to the mitochondria. The physiology of the resulting strains was evaluated in continuous cultivations with glycerol or glucose as the sole carbon source, as well as under hypoxia (on glucose). Cytosolic targeting of Pos5 NADH kinase resulted in lower biomass-substrate yields but allowed for a 2-fold increase in product specific productivity. In contrast, Pos5 NADH kinase targeting to the mitochondria did not affect growth physiology and recombinant protein production significantly. Growth physiological parameters were in silico evaluated using the recent upgraded version (v3.0) of the P. pastoris consensus genome-scale metabolic model iMT1026, providing insights on the impact of POS5 overexpression on metabolic flux distributions.IMPORTANCE Recombinant protein overproduction often results in oxidative stress, causing deviations from the optimal redox cofactor regeneration balance. This becomes one of the limiting factors in obtaining high levels of heterologous protein production. Overexpression of redox-affecting enzymes has been explored in other organisms, such as Saccharomyces cerevisiae, as a means to fine tune the cofactor regeneration balance in order to obtain higher protein titers. In the present work, this strategy is explored in P. pastoris In particular, one NADH kinase enzyme from S. cerevisiae (Pos5) is used, either in the cytosol or in mitochondria of P. pastoris, and its impact on the production of a model protein (antibody fragment) is evaluated. A significant improvement in the production of the model protein is observed when the kinase is directed to the cytosol. These results are significant in the field of heterologous protein production in general and in particular in the development of improved metabolic engineering strategies for P. pastoris.
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Affiliation(s)
- Màrius Tomàs-Gamisans
- Departament d'Enginyeria Química, Biològica i Ambiental, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Catalonia, Spain
| | - Cristiane Conte Paim Andrade
- Departament d'Enginyeria Química, Biològica i Ambiental, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Catalonia, Spain
| | - Francisco Maresca
- Departament d'Enginyeria Química, Biològica i Ambiental, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Catalonia, Spain
| | - Sergi Monforte
- Departament d'Enginyeria Química, Biològica i Ambiental, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Catalonia, Spain
| | - Pau Ferrer
- Departament d'Enginyeria Química, Biològica i Ambiental, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Catalonia, Spain
| | - Joan Albiol
- Departament d'Enginyeria Química, Biològica i Ambiental, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Catalonia, Spain
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Nijland JG, Driessen AJM. Engineering of Pentose Transport in Saccharomyces cerevisiae for Biotechnological Applications. Front Bioeng Biotechnol 2020; 7:464. [PMID: 32064252 PMCID: PMC7000353 DOI: 10.3389/fbioe.2019.00464] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 12/19/2019] [Indexed: 01/05/2023] Open
Abstract
Lignocellulosic biomass yields after hydrolysis, besides the hexose D-glucose, D-xylose, and L-arabinose as main pentose sugars. In second generation bioethanol production utilizing the yeast Saccharomyces cerevisiae, it is critical that all three sugars are co-consumed to obtain an economically feasible and robust process. Since S. cerevisiae is unable to metabolize pentose sugars, metabolic pathway engineering has been employed to introduce the respective pathways for D-xylose and L-arabinose metabolism. However, S. cerevisiae lacks specific pentose transporters, and these sugars enter the cell with low affinity via glucose transporters of the Hxt family. Therefore, in the presence of D-glucose, utilization of D-xylose and L-arabinose is poor as the Hxt transporters prefer D-glucose. To solve this problem, heterologous expression of pentose transporters has been attempted but often with limited success due to poor expression and stability, and/or low turnover. A more successful approach is the engineering of the endogenous Hxt transporter family and evolutionary selection for D-glucose insensitive growth on pentose sugars. This has led to the identification of a critical and conserved asparagine residue in Hxt transporters that, when mutated, reduces the D-glucose affinity while leaving the D-xylose affinity mostly unaltered. Likewise, mutant Gal2 transporter have been selected supporting specific uptake of L-arabinose. In fermentation experiments, the transporter mutants support efficient uptake and consumption of pentose sugars, and even co-consumption of D-xylose and D-glucose when used at industrial concentrations. Further improvements are obtained by interfering with the post-translational inactivation of Hxt transporters at high or low D-glucose concentrations. Transporter engineering solved major limitations in pentose transport in yeast, now allowing for co-consumption of sugars that is limited only by the rates of primary metabolism. This paves the way for a more economical second-generation biofuels production process.
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Affiliation(s)
- Jeroen G Nijland
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology, University of Groningen, Groningen, Netherlands
| | - Arnold J M Driessen
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology, University of Groningen, Groningen, Netherlands
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Guo J, Huang S, Chen Y, Guo X, Xiao D. Heterologous expression of Spathaspora passalidarum xylose reductase and xylitol dehydrogenase genes improved xylose fermentation ability of Aureobasidium pullulans. Microb Cell Fact 2018; 17:64. [PMID: 29712559 PMCID: PMC5925849 DOI: 10.1186/s12934-018-0911-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 04/24/2018] [Indexed: 11/16/2022] Open
Abstract
Background Aureobasidium pullulans is a yeast-like fungus that can ferment xylose to generate high-value-added products, such as pullulan, heavy oil, and melanin. The combinatorial expression of two xylose reductase (XR) genes and two xylitol dehydrogenase (XDH) genes from Spathaspora passalidarum and the heterologous expression of the Piromyces sp. xylose isomerase (XI) gene were induced in A. pullulans to increase the consumption capability of A. pullulans on xylose. Results The overexpression of XYL1.2 (encoding XR) and XYL2.2 (encoding XDH) was the most beneficial for xylose utilization, resulting in a 17.76% increase in consumed xylose compared with the parent strain, whereas the introduction of the Piromyces sp. XI pathway failed to enhance xylose utilization efficiency. Mutants with superior xylose fermentation performance exhibited increased intracellular reducing equivalents. The fermentation performance of all recombinant strains was not affected when glucose or sucrose was utilized as the carbon source. The strain with overexpression of XYL1.2 and XYL2.2 exhibited excellent fermentation performance with mimicked hydrolysate, and pullulan production increased by 97.72% compared with that of the parent strain. Conclusions The present work indicates that the P4 mutant (using the XR/XDH pathway) with overexpressed XYL1.2 and XYL2.2 exhibited the best xylose fermentation performance. The P4 strain showed the highest intracellular reducing equivalents and XR and XDH activity, with consequently improved pullulan productivity and reduced melanin production. This valuable development in aerobic fermentation by the P4 strain may provide guidance for the biotransformation of xylose to high-value products by A. pullulans through genetic approach. Electronic supplementary material The online version of this article (10.1186/s12934-018-0911-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jian Guo
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
| | - Siyao Huang
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
| | - Yefu Chen
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China.
| | - Xuewu Guo
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
| | - Dongguang Xiao
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
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Paramasivan K, Mutturi S. Regeneration of NADPH Coupled with HMG-CoA Reductase Activity Increases Squalene Synthesis in Saccharomyces cerevisiae. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:8162-8170. [PMID: 28845666 DOI: 10.1021/acs.jafc.7b02945] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Although overexpression of the tHMG1 gene is a well-known strategy for terpene synthesis in Saccharomyces cerevisiae, the optimal level for tHMG1p has not been established. In the present study, it was observed that two copies of the tHMG1 gene on a dual gene expression cassette improved squalene synthesis in laboratory strain by 16.8-fold in comparison to single-copy expression. It was also observed that tHMG1p is limited by its cofactor (NADPH), as the overexpression of NADPH regenerating genes', viz., ZWF1 and POS5 (full length and without mitochondrial presequence), has led to its increased enzyme activity. Further, it was demonstrated that overexpression of full-length POS5 has improved squalene synthesis in cytosol. Finally, when tHMG1 and full-length POS5 were co-overexpressed there was a net 27.5-fold increase in squalene when compared to control strain. These results suggest novel strategies to increase squalene accumulation in S. cerevisiae.
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Affiliation(s)
- Kalaivani Paramasivan
- Microbiology and Fermentation Technology Department, CSIR-Central Food Technological Research Institute , Mysore, India
- Academy of Scientific and Innovative Research , Mysore, New Delhi, India
| | - Sarma Mutturi
- Microbiology and Fermentation Technology Department, CSIR-Central Food Technological Research Institute , Mysore, India
- Academy of Scientific and Innovative Research , Mysore, New Delhi, India
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10
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Hou J, Qiu C, Shen Y, Li H, Bao X. Engineering of Saccharomyces cerevisiae for the efficient co-utilization of glucose and xylose. FEMS Yeast Res 2017; 17:3861258. [DOI: 10.1093/femsyr/fox034] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 06/02/2017] [Indexed: 11/14/2022] Open
Affiliation(s)
- Jin Hou
- State Key Laboratory of Microbial Technology, The School of Life Science, Shandong University, Jinan, 250100, China
| | - Chenxi Qiu
- State Key Laboratory of Microbial Technology, The School of Life Science, Shandong University, Jinan, 250100, China
| | - Yu Shen
- State Key Laboratory of Microbial Technology, The School of Life Science, Shandong University, Jinan, 250100, China
| | - Hongxing Li
- State Key Laboratory of Microbial Technology, The School of Life Science, Shandong University, Jinan, 250100, China
- Shandong Provincial Key Laboratory of Microbial Engineering, Qi Lu University of Technology, Jinan, 250353, China
| | - Xiaoming Bao
- State Key Laboratory of Microbial Technology, The School of Life Science, Shandong University, Jinan, 250100, China
- Shandong Provincial Key Laboratory of Microbial Engineering, Qi Lu University of Technology, Jinan, 250353, China
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11
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Zhang GC, Turner TL, Jin YS. Enhanced xylose fermentation by engineered yeast expressing NADH oxidase through high cell density inoculums. ACTA ACUST UNITED AC 2017; 44:387-395. [DOI: 10.1007/s10295-016-1899-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 12/25/2016] [Indexed: 12/22/2022]
Abstract
Abstract
Accumulation of reduced byproducts such as glycerol and xylitol during xylose fermentation by engineered Saccharomyces cerevisiae hampers the economic production of biofuels and chemicals from cellulosic hydrolysates. In particular, engineered S. cerevisiae expressing NADPH-linked xylose reductase (XR) and NAD+-linked xylitol dehydrogenase (XDH) produces substantial amounts of the reduced byproducts under anaerobic conditions due to the cofactor difference of XR and XDH. While the additional expression of a water-forming NADH oxidase (NoxE) from Lactococcus lactis in engineered S. cerevisiae with the XR/XDH pathway led to reduced glycerol and xylitol production and increased ethanol yields from xylose, volumetric ethanol productivities by the engineered yeast decreased because of growth defects from the overexpression of noxE. In this study, we introduced noxE into an engineered yeast strain (SR8) exhibiting near-optimal xylose fermentation capacity. To overcome the growth defect caused by the overexpression of noxE, we used a high cell density inoculum for xylose fermentation by the SR8 expressing noxE. The resulting strain, SR8N, not only showed a higher ethanol yield and lower byproduct yields, but also exhibited a high ethanol productivity during xylose fermentation. As noxE overexpression elicits a negligible growth defect on glucose conditions, the beneficial effects of noxE overexpression were substantial when a mixture of glucose and xylose was used. Consumption of glucose led to rapid cell growth and therefore enhanced the subsequent xylose fermentation. As a result, the SR8N strain produced more ethanol and fewer byproducts from a mixture of glucose and xylose than the parental SR8 strain without noxE overexpression. Our results suggest that the growth defects from noxE overexpression can be overcome in the case of fermenting lignocellulose-derived sugars such as glucose and xylose.
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Affiliation(s)
- Guo-Chang Zhang
- grid.35403.31 0000000419369991 Carl R. Woese Institute for Genomic Biology University of Illinois at Urbana-Champaign 1206 W. Gregory Drive 61801 Urbana IL USA
- grid.35403.31 0000000419369991 Department of Food Science and Human Nutrition University of Illinois at Urbana-Champaign 61801 Urbana IL USA
| | - Timothy L Turner
- grid.35403.31 0000000419369991 Department of Food Science and Human Nutrition University of Illinois at Urbana-Champaign 61801 Urbana IL USA
| | - Yong-Su Jin
- grid.35403.31 0000000419369991 Carl R. Woese Institute for Genomic Biology University of Illinois at Urbana-Champaign 1206 W. Gregory Drive 61801 Urbana IL USA
- grid.35403.31 0000000419369991 Department of Food Science and Human Nutrition University of Illinois at Urbana-Champaign 61801 Urbana IL USA
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12
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Guo W, Sheng J, Feng X. Synergizing 13C Metabolic Flux Analysis and Metabolic Engineering for Biochemical Production. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2017; 162:265-299. [PMID: 28424826 DOI: 10.1007/10_2017_2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Metabolic engineering of industrial microorganisms to produce chemicals, fuels, and drugs has attracted increasing interest as it provides an environment-friendly and renewable route that does not depend on depleting petroleum sources. However, the microbial metabolism is so complex that metabolic engineering efforts often have difficulty in achieving a satisfactory yield, titer, or productivity of the target chemical. To overcome this challenge, 13C Metabolic Flux Analysis (13C-MFA) has been developed to investigate rigorously the cell metabolism and quantify the carbon flux distribution in central metabolic pathways. In the past decade, 13C-MFA has been widely used in academic labs and the biotechnology industry to pinpoint the key issues related to microbial-based chemical production and to guide the development of the appropriate metabolic engineering strategies for improving the biochemical production. In this chapter we introduce the basics of 13C-MFA and illustrate how 13C-MFA has been applied to synergize with metabolic engineering to identify and tackle the rate-limiting steps in biochemical production.
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Affiliation(s)
- Weihua Guo
- Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
| | - Jiayuan Sheng
- Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA
| | - Xueyang Feng
- Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA.
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13
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Li H, Shen Y, Wu M, Hou J, Jiao C, Li Z, Liu X, Bao X. Engineering a wild-type diploid Saccharomyces cerevisiae strain for second-generation bioethanol production. BIORESOUR BIOPROCESS 2016; 3:51. [PMID: 27942436 PMCID: PMC5122614 DOI: 10.1186/s40643-016-0126-4] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Accepted: 11/11/2016] [Indexed: 11/24/2022] Open
Abstract
Background The cost-effective production of second-generation bioethanol, which is made from lignocellulosic materials, has to face the following two problems: co-fermenting xylose with glucose and enhancing the strain’s tolerance to lignocellulosic inhibitors. Based on our previous study, the wild-type diploid Saccharomyces cerevisiae strain BSIF with robustness and good xylose metabolism genetic background was used as a chassis for constructing efficient xylose-fermenting industrial strains. The performance of the resulting strains in the fermentation of media with sugars and hydrolysates was investigated. Results The following two novel heterologous genes were integrated into the genome of the chassis cell: the mutant MGT05196N360F, which encodes a xylose-specific, glucose-insensitive transporter and is derived from the Meyerozyma guilliermondii transporter gene MGT05196, and Ru-xylA (where Ru represents the rumen), which encodes a xylose isomerase (XI) with higher activity in S. cerevisiae. Additionally, endogenous modifications were also performed, including the overproduction of the xylulokinase Xks1p and the non-oxidative PPP (pentose phosphate pathway), and the inactivation of the aldose reductase Gre3p and the alkaline phosphatase Pho13p. These rationally designed genetic modifications, combined with alternating adaptive evolutions in xylose and SECS liquor (the leach liquor of steam-exploding corn stover), resulted in a final strain, LF1, with excellent xylose fermentation and enhanced inhibitor resistance. The specific xylose consumption rate of LF1 reached as high as 1.089 g g−1 h−1 with xylose as the sole carbon source. Moreover, its highly synchronized utilization of xylose and glucose was particularly significant; 77.6% of xylose was consumed along with glucose within 12 h, and the ethanol yield was 0.475 g g−1, which is more than 93% of the theoretical yield. Additionally, LF1 performed well in fermentations with two different lignocellulosic hydrolysates. Conclusion The strain LF1 co-ferments glucose and xylose efficiently and synchronously. This result highlights the great potential of LF1 for the practical production of second-generation bioethanol. Electronic supplementary material The online version of this article (doi:10.1186/s40643-016-0126-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hongxing Li
- State Key Laboratory of Microbial Technology, Shandong University, Shan Da Nan Road 27, Jinan, 250100 China.,Shandong Provincial Key Laboratory of Microbial Engineering, Qi Lu University of Technology, Jinan, 250353 China
| | - Yu Shen
- State Key Laboratory of Microbial Technology, Shandong University, Shan Da Nan Road 27, Jinan, 250100 China
| | - Meiling Wu
- State Key Laboratory of Microbial Technology, Shandong University, Shan Da Nan Road 27, Jinan, 250100 China
| | - Jin Hou
- State Key Laboratory of Microbial Technology, Shandong University, Shan Da Nan Road 27, Jinan, 250100 China
| | - Chunlei Jiao
- State Key Laboratory of Microbial Technology, Shandong University, Shan Da Nan Road 27, Jinan, 250100 China
| | - Zailu Li
- Shandong Provincial Key Laboratory of Microbial Engineering, Qi Lu University of Technology, Jinan, 250353 China
| | - Xinli Liu
- Shandong Provincial Key Laboratory of Microbial Engineering, Qi Lu University of Technology, Jinan, 250353 China
| | - Xiaoming Bao
- State Key Laboratory of Microbial Technology, Shandong University, Shan Da Nan Road 27, Jinan, 250100 China.,Shandong Provincial Key Laboratory of Microbial Engineering, Qi Lu University of Technology, Jinan, 250353 China
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14
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Dong X, Chen X, Qian Y, Wang Y, Wang L, Qiao W, Liu L. Metabolic engineering of Escherichia coli W3110 to produce L-malate. Biotechnol Bioeng 2016; 114:656-664. [PMID: 27668703 DOI: 10.1002/bit.26190] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 09/05/2016] [Accepted: 09/19/2016] [Indexed: 11/07/2022]
Abstract
A four-carbon dicarboxylic acid L-malate has recently attracted attention due to its potential applications in the fields of medicine and agriculture. In this study, Escherichia coli W3110 was engineered and optimized for L-malate production via one-step L-malate synthesis pathway. First, deletion of the genes encoding lactate dehydrogenase (ldhA), pyruvate oxidase (poxB), pyruvate formate lyase (pflB), phosphotransacetylase (pta), and acetate kinase A (ackA) in pta-ackA pathway led to accumulate 20.9 g/L pyruvate. Then, overexpression of NADP+ -dependent malic enzyme C490S mutant in this multi-deletion mutant resulted in the direct conversion of pyruvate into L-malate (3.62 g/L). Next, deletion of the genes responsible for succinate biosynthesis further enhanced L-malate production up to 7.78 g/L. Finally, L-malate production was elevated to 21.65 g/L with the L-malate yield to 0.36 g/g in a 5 L bioreactor by overexpressing the pos5 gene encoding NADH kinase in the engineered E. coli F0931 strain. This study demonstrates the potential utility of one-step pathway for efficient L-malate production. Biotechnol. Bioeng. 2017;114: 656-664. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Xiaoxiang Dong
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,Laboratory of Food Microbial-Manufacturing Engineering, Jiangnan University, Wuxi, China
| | - Xiulai Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,Laboratory of Food Microbial-Manufacturing Engineering, Jiangnan University, Wuxi, China
| | - Yuanyuan Qian
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,Laboratory of Food Microbial-Manufacturing Engineering, Jiangnan University, Wuxi, China
| | - Yuancai Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,Laboratory of Food Microbial-Manufacturing Engineering, Jiangnan University, Wuxi, China
| | - Li Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,Laboratory of Food Microbial-Manufacturing Engineering, Jiangnan University, Wuxi, China
| | - Weihua Qiao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,Laboratory of Food Microbial-Manufacturing Engineering, Jiangnan University, Wuxi, China
| | - Liming Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,Laboratory of Food Microbial-Manufacturing Engineering, Jiangnan University, Wuxi, China
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15
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Shalley Sharma, Sonia Sharma, Surender Singh, Lata, Anju Arora. Improving Yeast Strains for Pentose Hexose Co-fermentation: Successes and Hurdles. SPRINGER PROCEEDINGS IN ENERGY 2016. [DOI: 10.1007/978-81-322-2773-1_3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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16
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13C-Metabolic Flux Analysis: An Accurate Approach to Demystify Microbial Metabolism for Biochemical Production. Bioengineering (Basel) 2015; 3:bioengineering3010003. [PMID: 28952565 PMCID: PMC5597161 DOI: 10.3390/bioengineering3010003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 12/10/2015] [Accepted: 12/18/2015] [Indexed: 12/15/2022] Open
Abstract
Metabolic engineering of various industrial microorganisms to produce chemicals, fuels, and drugs has raised interest since it is environmentally friendly, sustainable, and independent of nonrenewable resources. However, microbial metabolism is so complex that only a few metabolic engineering efforts have been able to achieve a satisfactory yield, titer or productivity of the target chemicals for industrial commercialization. In order to overcome this challenge, 13C Metabolic Flux Analysis (13C-MFA) has been continuously developed and widely applied to rigorously investigate cell metabolism and quantify the carbon flux distribution in central metabolic pathways. In the past decade, many 13C-MFA studies have been performed in academic labs and biotechnology industries to pinpoint key issues related to microbe-based chemical production. Insightful information about the metabolic rewiring has been provided to guide the development of the appropriate metabolic engineering strategies for improving the biochemical production. In this review, we will introduce the basics of 13C-MFA and illustrate how 13C-MFA has been applied via integration with metabolic engineering to identify and tackle the rate-limiting steps in biochemical production for various host microorganisms
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17
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Kim S, Hahn JS. Efficient production of 2,3-butanediol in Saccharomyces cerevisiae by eliminating ethanol and glycerol production and redox rebalancing. Metab Eng 2015; 31:94-101. [DOI: 10.1016/j.ymben.2015.07.006] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 06/24/2015] [Accepted: 07/17/2015] [Indexed: 12/18/2022]
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18
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Kim JW, Seo SO, Zhang GC, Jin YS, Seo JH. Expression of Lactococcus lactis NADH oxidase increases 2,3-butanediol production in Pdc-deficient Saccharomyces cerevisiae. BIORESOURCE TECHNOLOGY 2015; 191:512-9. [PMID: 25769689 DOI: 10.1016/j.biortech.2015.02.077] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Revised: 02/16/2015] [Accepted: 02/19/2015] [Indexed: 05/04/2023]
Abstract
To minimize glycerol production during 2,3-BD fermentation by the engineered Saccharomyces cerevisiae, the Lactococcus lactis water-forming NADH oxidase gene (noxE) was expressed at five different levels. The expression of NADH oxidase substantially decreased the intracellular NADH/NAD(+) ratio. The S. cerevisiae BD5_T2nox strain expressing noxE produced 2,3-BD with yield of 0.359 g 2,3-BD/gglucose and glycerol with 0.069gglycerol/gglucose, which are 23.8% higher and 65.3% lower than those of the isogenic strain without noxE. These results demonstrate that the carbon flux could be redirected from glycerol to 2,3-BD through alteration of the NADH/NAD(+) ratio by the expression of NADH oxidase.
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Affiliation(s)
- Jin-Woo Kim
- Department of Agricultural Biotechnology and Center for Food and Bioconvergence, Seoul National University, Seoul 151-921, Republic of Korea
| | - Seung-Oh Seo
- Department of Food Science and Human Nutrition, and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Guo-Chang Zhang
- Department of Food Science and Human Nutrition, and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Yong-Su Jin
- Department of Food Science and Human Nutrition, and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Jin-Ho Seo
- Department of Agricultural Biotechnology and Center for Food and Bioconvergence, Seoul National University, Seoul 151-921, Republic of Korea.
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19
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Hou J, Suo F, Wang C, Li X, Shen Y, Bao X. Fine-tuning of NADH oxidase decreases byproduct accumulation in respiration deficient xylose metabolic Saccharomyces cerevisiae. BMC Biotechnol 2014; 14:13. [PMID: 24529074 PMCID: PMC3928090 DOI: 10.1186/1472-6750-14-13] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 02/08/2014] [Indexed: 01/01/2023] Open
Abstract
Background Efficiently utilizing all available carbon from lignocellulosic feedstock presents a major barrier to the production of economically feasible biofuel. Previously, to enable xylose utilization, we introduced a cofactor-dependent xylose reductase (XR) and xylitol dehydrogenase (XDH) pathway, or a cofactor-independent xylose isomerase (XI) pathway, into Saccharomyces cerevisiae. The resulting strains metabolized xylose with high efficiency. However, in both pathway recombinant strains, the cofactor imbalance caused accumulation of the byproducts glycerol and/or xylitol and reduced the ethanol production efficiency. Results In this study, we introduced NADH oxidase from Lactococcus lactis into both XI and XR-XDH pathway recombinant strains. To reduce byproduct accumulation while maintaining xylose metabolism, we optimized the expression level of NADH oxidase by comparing its expression under the control of different promoters and plasmids. In recombinant XI strains, NADH oxidase was expressed at different levels, regulated by the GPD2 promoter or TEF1 promoter in the 2 μ plasmid. The expression under the control of GPD2 promoter decreased glycerol production by 84% and increased the ethanol yield and specific growth rate by 8% and 12%, respectively. In contrast, in the recombinant XR-XDH strains, such expression level was not efficient enough to decrease the byproduct accumulation. Therefore, higher NADH oxidase expression levels were tested. In the strain expressing NADH oxidase under the control of the TEF1 promoter in the centromeric plasmids, xylitol and glycerol production were reduced by 60% and 83%, respectively, without significantly affecting xylose consumption. Conclusions By fine-tuning NADH oxidase expression, we decreased the glycerol or/and xylitol production in both recombinant XI and XR-XDH xylose-metabolizing yeast strains. The optimal NADH oxidase expression levels depend on metabolic pathways. Similar cofactor engineering strategies could maximize the production of other redox dependent metabolites.
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Affiliation(s)
| | | | | | | | | | - Xiaoming Bao
- State Key Laboratory of Microbial Technology, Shandong University, Shanda Nan Road 27, Jinan 250100, China.
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20
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Salusjärvi L, Kaunisto S, Holmström S, Vehkomäki ML, Koivuranta K, Pitkänen JP, Ruohonen L. Overexpression of NADH-dependent fumarate reductase improves D-xylose fermentation in recombinant Saccharomyces cerevisiae. J Ind Microbiol Biotechnol 2013; 40:1383-92. [PMID: 24113892 DOI: 10.1007/s10295-013-1344-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 09/09/2013] [Indexed: 01/31/2023]
Abstract
Deviation from optimal levels and ratios of redox cofactors NAD(H) and NADP(H) is common when microbes are metabolically engineered. The resulting redox imbalance often reduces the rate of substrate utilization as well as biomass and product formation. An example is the metabolism of D-xylose by recombinant Saccharomyces cerevisiae strains expressing xylose reductase and xylitol dehydrogenase encoding genes from Scheffersomyces stipitis. This pathway requires both NADPH and NAD(+). The effect of overexpressing the glycosomal NADH-dependent fumarate reductase (FRD) of Trypanosoma brucei in D-xylose-utilizing S. cerevisiae alone and together with an endogenous, cytosol directed NADH-kinase (POS5Δ17) was studied as one possible solution to overcome this imbalance. Expression of FRD and FRD + POS5Δ17 resulted in 60 and 23 % increase in ethanol yield, respectively, on D-xylose under anaerobic conditions. At the same time, xylitol yield decreased in the FRD strain suggesting an improvement in redox balance. We show that fumarate reductase of T. brucei can provide an important source of NAD(+) in yeast under anaerobic conditions, and can be useful for metabolic engineering strategies where the redox cofactors need to be balanced. The effects of FRD and NADH-kinase on aerobic and anaerobic D-xylose and D-glucose metabolism are discussed.
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Affiliation(s)
- Laura Salusjärvi
- VTT, Technical Research Centre of Finland, PO Box 1000, 02044, VTT, Finland,
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21
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Engineering of the glycerol decomposition pathway and cofactor regulation in an industrial yeast improves ethanol production. J Ind Microbiol Biotechnol 2013; 40:1153-60. [PMID: 23896974 PMCID: PMC3769588 DOI: 10.1007/s10295-013-1311-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Accepted: 07/08/2013] [Indexed: 11/24/2022]
Abstract
Glycerol is a major by-product of industrial ethanol production and its formation consumes up to 4 % of the sugar substrate. This study modified the glycerol decomposition pathway of an industrial strain of Saccharomyces cerevisiae to optimize the consumption of substrate and yield of ethanol. This study is the first to couple glycerol degradation with ethanol formation, to the best of our knowledge. The recombinant strain overexpressing GCY1 and DAK1, encoding glycerol dehydrogenase and dihydroxyacetone kinase, respectively, in glycerol degradation pathway, exhibited a moderate increase in ethanol yield (2.9 %) and decrease in glycerol yield (24.9 %) compared to the wild type with the initial glucose concentration of 15 % under anaerobic conditions. However, when the mhpF gene, encoding acetylating NAD+-dependent acetaldehyde dehydrogenase from Escherichia coli, was co-expressed in the aforementioned recombinant strain, a further increase in ethanol yield by 5.5 % and decrease in glycerol yield by 48 % were observed for the resultant recombinant strain GDMS1 when acetic acid was added into the medium prior to inoculation compared to the wild type. The process outlined in this study which enhances glycerol consumption and cofactor regulation in an industrial yeast is a promising metabolic engineering strategy to increase ethanol production by reducing the formation of glycerol.
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22
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Wang Y, San KY, Bennett GN. Cofactor engineering for advancing chemical biotechnology. Curr Opin Biotechnol 2013; 24:994-9. [PMID: 23611567 DOI: 10.1016/j.copbio.2013.03.022] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 03/21/2013] [Accepted: 03/22/2013] [Indexed: 11/26/2022]
Abstract
Cofactors provide redox carriers for biosynthetic reactions, catabolic reactions and act as important agents in transfer of energy for the cell. Recent advances in manipulating cofactors include culture conditions or additive alterations, genetic modification of host pathways for increased availability of desired cofactor, changes in enzyme cofactor specificity, and introduction of novel redox partners to form effective circuits for biochemical processes and biocatalysts. Genetic strategies to employ ferredoxin, NADH and NADPH most effectively in natural or novel pathways have improved yield and efficiency of large-scale processes for fuels and chemicals and have been demonstrated with a variety of microbial organisms.
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Affiliation(s)
- Yipeng Wang
- Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77005, USA
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23
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Kim SR, Kwee NR, Kim H, Jin YS. Feasibility of xylose fermentation by engineered Saccharomyces cerevisiae overexpressing endogenous aldose reductase (GRE3), xylitol dehydrogenase (XYL2), and xylulokinase (XYL3) from Scheffersomyces stipitis. FEMS Yeast Res 2013; 13:312-21. [PMID: 23398717 DOI: 10.1111/1567-1364.12036] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2012] [Revised: 02/04/2013] [Accepted: 02/05/2013] [Indexed: 11/27/2022] Open
Abstract
Saccharomyces cerevisiae has been engineered for producing ethanol from xylose, the second most abundant sugar in cellulosic biomass hydrolyzates. Heterologous expressions of xylose reductase (XYL1) and xylitol dehydrogenase (XYL2), or of xylose isomerase (xylA), either case of which being accompanied by overexpression of xylulokinase (XKS1 or XYL3), are known as the prevalent strategies for metabolic engineering of S. cerevisiae to ferment xylose. In this study, we propose an alternative strategy that employs overexpression of GRE3 coding for endogenous aldose reductase instead of XYL1 to construct efficient xylose-fermenting S. cerevisiae. Replacement of XYL1 with GRE3 has been regarded as an undesirable approach because NADPH-specific aldose reductase (GRE3) would aggravate redox balance with xylitol dehydrogenase (XYL2) using NAD(+) exclusively. Here, we demonstrate that engineered S. cerevisiae overexpressing GRE3, XYL2, and XYL3 can ferment xylose as well as a mixture of glucose and xylose with higher ethanol yields (0.29-0.41 g g(-1) sugars) and productivities (0.13-0.85 g L(-1) h(-1)) than those (0.23-0.39 g g(-1) sugars, 0.10-0.74 g L(-1) h(-1)) of an isogenic strain overexpressing XYL1, XYL2, and XYL3 under oxygen-limited conditions. We found that xylose fermentation efficiency of a strain overexpressing GRE3 was dramatically increased by high expression levels of XYL2. Our results suggest that optimized expression levels of GRE3, XYL2, and XYL3 could overcome redox imbalance during xylose fermentation by engineered S. cerevisiae under oxygen-limited conditions.
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Affiliation(s)
- Soo Rin Kim
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61802, USA
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24
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Hickert LR, da Cunha-Pereira F, de Souza-Cruz PB, Rosa CA, Ayub MAZ. Ethanogenic fermentation of co-cultures of Candida shehatae HM 52.2 and Saccharomyces cerevisiae ICV D254 in synthetic medium and rice hull hydrolysate. BIORESOURCE TECHNOLOGY 2013; 131:508-514. [PMID: 23391739 DOI: 10.1016/j.biortech.2012.12.135] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 12/18/2012] [Accepted: 12/19/2012] [Indexed: 06/01/2023]
Abstract
The ability of Candida shehatae, Saccharomyces cerevisiae, or the combination of these two yeasts in converting the mixed sugar composition of rice hull hydrolysate (RHH) as substrate for ethanol production is presented. In shake flask experiments, co-cultures showed ethanol yields (YP/S) of 0.42 and 0.51 in synthetic medium simulating the sugar composition of RHH and in RHH, respectively, with both glucose and xylose being completely depleted, while pure cultures of C. shehatae produced slightly lower ethanol yields (0.40). Experiments were scaled-up to bioreactors, in which anaerobiosis and oxygen limitation conditions were tested. Bioreactor co-cultures produced similar ethanol yields in both conditions (0.50-0.51) in synthetic medium, while in RHH, yields of 0.48 and 0.44 were obtained, respectively. The results showed near-theoretical yields of ethanol. Results suggest the feasibility of co-cultures of C. shehatae, a newly isolated strain, and S. cerevisiae in RHH as substrate for second-generation ethanol production.
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Affiliation(s)
- Lilian Raquel Hickert
- Biotechnology & Biochemical Engineering Laboratory (BiotecLab), Federal University of Rio Grande do Sul, Av., Bento Gonçalves, 9500, P.O. Box 15090, ZC 91501-970, Porto Alegre, RS, Brazil
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25
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Liu CG, Xue C, Lin YH, Bai FW. Redox potential control and applications in microaerobic and anaerobic fermentations. Biotechnol Adv 2012. [PMID: 23178703 DOI: 10.1016/j.biotechadv.2012.11.005] [Citation(s) in RCA: 142] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Many fermentation products are produced under microaerobic or anaerobic conditions, in which oxygen is undetectable by dissolved oxygen probe, presenting a challenge for process monitoring and control. Extracellular redox potentials that can be detected conveniently affect intracellular redox homeostasis and metabolism, and consequently control profiles of fermentation products, which provide an alternative for monitoring and control of these fermentation processes. This article reviews updated progress in the impact of redox potentials on gene expression, protein biosynthesis and metabolism as well as redox potential control strategies for more efficient production of fermentation products, taking ethanol fermentation by the yeast Saccharomyces under microaerobic conditions and butanol production by the bacterium Clostridium under anaerobic conditions as examples.
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Affiliation(s)
- Chen-Guang Liu
- School of Life Sciences and Biotechnology, Dalian University of Technology, Dalian 116023, China
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26
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Lee WH, Kim JW, Park EH, Han NS, Kim MD, Seo JH. Effects of NADH kinase on NADPH-dependent biotransformation processes in Escherichia coli. Appl Microbiol Biotechnol 2012; 97:1561-9. [PMID: 23053084 DOI: 10.1007/s00253-012-4431-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Revised: 09/07/2012] [Accepted: 09/10/2012] [Indexed: 11/26/2022]
Abstract
Sufficient supply of NADPH is one of the most important factors affecting the productivity of biotransformation processes. In this study, construction of an efficient NADPH-regenerating system was attempted using direct phosphorylation of NADH by NADH kinase (Pos5p) from Saccharomyces cerevisiae for producing guanosine diphosphate (GDP)-L-fucose and ε-caprolactone in recombinant Escherichia coli. Expression of Pos5p in a fed-batch culture of recombinant E. coli producing GDP-L-fucose resulted in a maximum GDP-L-fucose concentration of 291.5 mg/l, which corresponded to a 51 % enhancement compared with the control strain. In a fed-batch Baeyer-Villiger (BV) oxidation of cyclohexanone using recombinant E. coli expressing Pos5p, a maximum ε-caprolactone concentration of 21.6 g/l was obtained, which corresponded to a 96 % enhancement compared with the control strain. Such an increase might be due to the enhanced availability of NADPH in recombinant E. coli expressing Pos5p. These results suggested that efficient regeneration of NADPH was possible by functional expression of Pos5p in recombinant E. coli, which can be applied to other NADPH-dependent biotransformation processes in E. coli.
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Affiliation(s)
- Won-Heong Lee
- Department of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University, Seoul, 151-921, Korea
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Kim SR, Ha SJ, Wei N, Oh EJ, Jin YS. Simultaneous co-fermentation of mixed sugars: a promising strategy for producing cellulosic ethanol. Trends Biotechnol 2012; 30:274-82. [DOI: 10.1016/j.tibtech.2012.01.005] [Citation(s) in RCA: 162] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 01/23/2012] [Accepted: 01/24/2012] [Indexed: 11/29/2022]
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A genome shuffling-generated Saccharomyces cerevisiae isolate that ferments xylose and glucose to produce high levels of ethanol. ACTA ACUST UNITED AC 2012; 39:777-87. [DOI: 10.1007/s10295-011-1076-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2010] [Accepted: 12/15/2011] [Indexed: 11/26/2022]
Abstract
Abstract
Genome shuffling is an efficient approach for the rapid improvement of industrially important microbial phenotypes. This report describes optimized conditions for protoplast preparation, regeneration, inactivation, and fusion using the Saccharomyces cerevisiae W5 strain. Ethanol production was confirmed by TTC (triphenyl tetrazolium chloride) screening and high-performance liquid chromatography (HPLC). A genetically stable, high ethanol-producing strain that fermented xylose and glucose was obtained following three rounds of genome shuffling. After fermentation for 84 h, the high ethanol-producing S. cerevisiae GS3-10 strain (which utilized 69.48 and 100% of the xylose and glucose stores, respectively) produced 26.65 g/L ethanol, i.e., 47.08% higher than ethanol production by S. cerevisiae W5 (18.12 g/L). The utilization ratios of xylose and glucose were 69.48 and 100%, compared to 14.83 and 100% for W5, respectively. The ethanol yield was 0.40 g/g (ethanol/consumed glucose and xylose), i.e., 17.65% higher than the yield by S. cerevisiae W5 (0.34 g/g).
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Hou J, Tyo K, Liu Z, Petranovic D, Nielsen J. Engineering of vesicle trafficking improves heterologous protein secretion in Saccharomyces cerevisiae. Metab Eng 2012; 14:120-7. [DOI: 10.1016/j.ymben.2012.01.002] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Revised: 12/20/2011] [Accepted: 01/05/2012] [Indexed: 11/15/2022]
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Shi S, Valle-Rodríguez JO, Khoomrung S, Siewers V, Nielsen J. Functional expression and characterization of five wax ester synthases in Saccharomyces cerevisiae and their utility for biodiesel production. BIOTECHNOLOGY FOR BIOFUELS 2012; 5:7. [PMID: 22364438 PMCID: PMC3309958 DOI: 10.1186/1754-6834-5-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 02/24/2012] [Indexed: 05/24/2023]
Abstract
BACKGROUND Wax ester synthases (WSs) can synthesize wax esters from alcohols and fatty acyl coenzyme A thioesters. The knowledge of the preferred substrates for each WS allows the use of yeast cells for the production of wax esters that are high-value materials and can be used in a variety of industrial applications. The products of WSs include fatty acid ethyl esters, which can be directly used as biodiesel. RESULTS Here, heterologous WSs derived from five different organisms were successfully expressed and evaluated for their substrate preference in Saccharomyces cerevisiae. We investigated the potential of the different WSs for biodiesel (that is, fatty acid ethyl esters) production in S. cerevisiae. All investigated WSs, from Acinetobacter baylyi ADP1, Marinobacter hydrocarbonoclasticus DSM 8798, Rhodococcus opacus PD630, Mus musculus C57BL/6 and Psychrobacter arcticus 273-4, have different substrate specificities, but they can all lead to the formation of biodiesel. The best biodiesel producing strain was found to be the one expressing WS from M. hydrocarbonoclasticus DSM 8798 that resulted in a biodiesel titer of 6.3 mg/L. To further enhance biodiesel production, acetyl coenzyme A carboxylase was up-regulated, which resulted in a 30% increase in biodiesel production. CONCLUSIONS Five WSs from different species were functionally expressed and their substrate preference characterized in S. cerevisiae, thus constructing cell factories for the production of specific kinds of wax ester. WS from M. hydrocarbonoclasticus showed the highest preference for ethanol compared to the other WSs, and could permit the engineered S. cerevisiae to produce biodiesel.
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Affiliation(s)
- Shuobo Shi
- Department of Chemical and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE 412 96, Göteborg, Sweden
| | - Juan Octavio Valle-Rodríguez
- Department of Chemical and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE 412 96, Göteborg, Sweden
| | - Sakda Khoomrung
- Department of Chemical and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE 412 96, Göteborg, Sweden
| | - Verena Siewers
- Department of Chemical and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE 412 96, Göteborg, Sweden
| | - Jens Nielsen
- Department of Chemical and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE 412 96, Göteborg, Sweden
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Shi S, Valle-Rodríguez JO, Khoomrung S, Siewers V, Nielsen J. Functional expression and characterization of five wax ester synthases in Saccharomyces cerevisiae and their utility for biodiesel production. BIOTECHNOLOGY FOR BIOFUELS 2012. [PMID: 22364438 DOI: 10.1186/preaccept-1932279820621895] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
BACKGROUND Wax ester synthases (WSs) can synthesize wax esters from alcohols and fatty acyl coenzyme A thioesters. The knowledge of the preferred substrates for each WS allows the use of yeast cells for the production of wax esters that are high-value materials and can be used in a variety of industrial applications. The products of WSs include fatty acid ethyl esters, which can be directly used as biodiesel. RESULTS Here, heterologous WSs derived from five different organisms were successfully expressed and evaluated for their substrate preference in Saccharomyces cerevisiae. We investigated the potential of the different WSs for biodiesel (that is, fatty acid ethyl esters) production in S. cerevisiae. All investigated WSs, from Acinetobacter baylyi ADP1, Marinobacter hydrocarbonoclasticus DSM 8798, Rhodococcus opacus PD630, Mus musculus C57BL/6 and Psychrobacter arcticus 273-4, have different substrate specificities, but they can all lead to the formation of biodiesel. The best biodiesel producing strain was found to be the one expressing WS from M. hydrocarbonoclasticus DSM 8798 that resulted in a biodiesel titer of 6.3 mg/L. To further enhance biodiesel production, acetyl coenzyme A carboxylase was up-regulated, which resulted in a 30% increase in biodiesel production. CONCLUSIONS Five WSs from different species were functionally expressed and their substrate preference characterized in S. cerevisiae, thus constructing cell factories for the production of specific kinds of wax ester. WS from M. hydrocarbonoclasticus showed the highest preference for ethanol compared to the other WSs, and could permit the engineered S. cerevisiae to produce biodiesel.
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Affiliation(s)
- Shuobo Shi
- Department of Chemical and Biological Engineering, Chalmers University of Technology, Kemivägen 10, SE 412 96, Göteborg, Sweden.
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Abstract
Conversion of plant cell walls to ethanol constitutes second generation bioethanol production. The process consists of several steps: biomass selection/genetic modification, physiochemical pretreatment, enzymatic saccharification, fermentation and separation. Ultimately, it is desirable to combine as many of the biochemical steps as possible in a single organism to achieve CBP (consolidated bioprocessing). A commercially ready CBP organism is currently unreported. Production of second generation bioethanol is hindered by economics, particularly in the cost of pretreatment (including waste management and solvent recovery), the cost of saccharification enzymes (particularly exocellulases and endocellulases displaying kcat ~1 s−1 on crystalline cellulose), and the inefficiency of co-fermentation of 5- and 6-carbon monosaccharides (owing in part to redox cofactor imbalances in Saccharomyces cerevisiae).
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Decreased xylitol formation during xylose fermentation in Saccharomyces cerevisiae due to overexpression of water-forming NADH oxidase. Appl Environ Microbiol 2011; 78:1081-6. [PMID: 22156411 DOI: 10.1128/aem.06635-11] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The recombinant xylose-fermenting Saccharomyces cerevisiae strain harboring xylose reductase (XR) and xylitol dehydrogenase (XDH) from Scheffersomyces stipitis requires NADPH and NAD(+), creates cofactor imbalance, and causes xylitol accumulation during growth on d-xylose. To solve this problem, noxE, encoding a water-forming NADH oxidase from Lactococcus lactis driven by the PGK1 promoter, was introduced into the xylose-utilizing yeast strain KAM-3X. A cofactor microcycle was set up between the utilization of NAD(+) by XDH and the formation of NAD(+) by water-forming NADH oxidase. Overexpression of noxE significantly decreased xylitol formation and increased final ethanol production during xylose fermentation. Under xylose fermentation conditions with an initial d-xylose concentration of 50 g/liter, the xylitol yields for of KAM-3X(pPGK1-noxE) and control strain KAM-3X were 0.058 g/g xylose and 0.191 g/g, respectively, which showed a 69.63% decrease owing to noxE overexpression; the ethanol yields were 0.294 g/g for KAM-3X(pPGK1-noxE) and 0.211 g/g for the control strain KAM-3X, which indicated a 39.33% increase due to noxE overexpression. At the same time, the glycerol yield also was reduced by 53.85% on account of the decrease in the NADH pool caused by overexpression of noxE.
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Current awareness on yeast. Yeast 2009. [DOI: 10.1002/yea.1623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Ethanol production from xylose in engineered Saccharomyces cerevisiae strains: current state and perspectives. Appl Microbiol Biotechnol 2009; 84:37-53. [DOI: 10.1007/s00253-009-2101-x] [Citation(s) in RCA: 274] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 06/18/2009] [Accepted: 06/18/2009] [Indexed: 12/20/2022]
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