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Vargas BDO, dos Santos JR, Pereira GAG, de Mello FDSB. An atlas of rational genetic engineering strategies for improved xylose metabolism in Saccharomyces cerevisiae. PeerJ 2023; 11:e16340. [PMID: 38047029 PMCID: PMC10691383 DOI: 10.7717/peerj.16340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 10/03/2023] [Indexed: 12/05/2023] Open
Abstract
Xylose is the second most abundant carbohydrate in nature, mostly present in lignocellulosic material, and representing an appealing feedstock for molecule manufacturing through biotechnological routes. However, Saccharomyces cerevisiae-a microbial cell widely used industrially for ethanol production-is unable to assimilate this sugar. Hence, in a world with raising environmental awareness, the efficient fermentation of pentoses is a crucial bottleneck to producing biofuels from renewable biomass resources. In this context, advances in the genetic mapping of S. cerevisiae have contributed to noteworthy progress in the understanding of xylose metabolism in yeast, as well as the identification of gene targets that enable the development of tailored strains for cellulosic ethanol production. Accordingly, this review focuses on the main strategies employed to understand the network of genes that are directly or indirectly related to this phenotype, and their respective contributions to xylose consumption in S. cerevisiae, especially for ethanol production. Altogether, the information in this work summarizes the most recent and relevant results from scientific investigations that endowed S. cerevisiae with an outstanding capability for commercial ethanol production from xylose.
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Affiliation(s)
- Beatriz de Oliveira Vargas
- Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, Universidade Estadual de Campinas, Campinas, Brazil
| | - Jade Ribeiro dos Santos
- Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, Universidade Estadual de Campinas, Campinas, Brazil
| | - Gonçalo Amarante Guimarães Pereira
- Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, Universidade Estadual de Campinas, Campinas, Brazil
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Persson VC, Perruca Foncillas R, Anderes TR, Ginestet C, Gorwa-Grauslund M. Impact of xylose epimerase on sugar assimilation and sensing in recombinant Saccharomyces cerevisiae carrying different xylose-utilization pathways. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:168. [PMID: 37932829 PMCID: PMC10629123 DOI: 10.1186/s13068-023-02422-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 10/28/2023] [Indexed: 11/08/2023]
Abstract
BACKGROUND Over the last decades, many strategies to procure and improve xylose consumption in Saccharomyces cerevisiae have been reported. This includes the introduction of efficient xylose-assimilating enzymes, the improvement of xylose transport, or the alteration of the sugar signaling response. However, different strain backgrounds are often used, making it difficult to determine if the findings are transferrable both to other xylose-consuming strains and to other xylose-assimilation pathways. For example, the influence of anomerization rates between α- and β-xylopyranose in pathway optimization and sugar sensing is relatively unexplored. RESULTS In this study, we tested the effect of expressing a xylose epimerase in S. cerevisiae strains carrying different xylose-consuming routes. First, XIs originating from three different species in isogenic S. cerevisiae strains were tested and the XI from Lachnoclostridium phytofermentans was found to give the best performance. The benefit of increasing the anomerization rate of xylose by adding a xylose epimerase to the XI strains was confirmed, as higher biomass formation and faster xylose consumption were obtained. However, the impact of xylose epimerase was XI-dependent, indicating that anomer preference may differ from enzyme to enzyme. The addition of the xylose epimerase in xylose reductase/xylitol dehydrogenase (XR/XDH)-carrying strains gave no improvement in xylose assimilation, suggesting that the XR from Spathaspora passalidarum had no anomer preference, in contrast to other reported XRs. The reduction in accumulated xylitol that was observed when the xylose epimerase was added may be associated with the upregulation of genes encoding endogenous aldose reductases which could be affected by the anomerization rate. Finally, xylose epimerase addition did not affect the sugar signaling, whereas the type of xylose pathway (XI vs. XR/XDH) did. CONCLUSIONS Although xylose anomer specificity is often overlooked, the addition of xylose epimerase should be considered as a key engineering step, especially when using the best-performing XI enzyme from L. phytofermentans. Additional research into the binding mechanism of xylose is needed to elucidate the enzyme-specific effect and decrease in xylitol accumulation. Finally, the differences in sugar signaling responses between XI and XR/XDH strains indicate that either the redox balance or the growth rate impacts the SNF1/Mig1p sensing pathway.
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Affiliation(s)
- Viktor C Persson
- Division of Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden
| | | | - Tegan R Anderes
- Division of Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden
| | - Clément Ginestet
- Division of Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden
| | - Marie Gorwa-Grauslund
- Division of Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden.
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Knychala MM, dos Santos AA, Kretzer LG, Gelsleichter F, Leandro MJ, Fonseca C, Stambuk BU. Strategies for Efficient Expression of Heterologous Monosaccharide Transporters in Saccharomyces cerevisiae. J Fungi (Basel) 2022; 8:jof8010084. [PMID: 35050024 PMCID: PMC8778384 DOI: 10.3390/jof8010084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/09/2022] [Accepted: 01/12/2022] [Indexed: 02/01/2023] Open
Abstract
In previous work, we developed a Saccharomyces cerevisiae strain (DLG-K1) lacking the main monosaccharide transporters (hxt-null) and displaying high xylose reductase, xylitol dehydrogenase and xylulokinase activities. This strain proved to be a useful chassis strain to study new glucose/xylose transporters, as SsXUT1 from Scheffersomyces stipitis. Proteins with high amino acid sequence similarity (78–80%) to SsXUT1 were identified from Spathaspora passalidarum and Spathaspora arborariae genomes. The characterization of these putative transporter genes (SpXUT1 and SaXUT1, respectively) was performed in the same chassis strain. Surprisingly, the cloned genes could not restore the ability to grow in several monosaccharides tested (including glucose and xylose), but after being grown in maltose, the uptake of 14C-glucose and 14C-xylose was detected. While SsXUT1 lacks lysine residues with high ubiquitinylation potential in its N-terminal domain and displays only one in its C-terminal domain, both SpXUT1 and SaXUT1 transporters have several such residues in their C-terminal domains. A truncated version of SpXUT1 gene, deprived of the respective 3′-end, was cloned in DLG-K1 and allowed growth and fermentation in glucose or xylose. In another approach, two arrestins known to be involved in the ubiquitinylation and endocytosis of sugar transporters (ROD1 and ROG3) were knocked out, but only the rog3 mutant allowed a significant improvement of growth and fermentation in glucose when either of the XUT permeases were expressed. Therefore, for the efficient heterologous expression of monosaccharide (e.g., glucose/xylose) transporters in S. cerevisiae, we propose either the removal of lysines involved in ubiquitinylation and endocytosis or the use of chassis strains hampered in the specific mechanism of membrane protein turnover.
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Affiliation(s)
- Marilia M. Knychala
- Center of Biological Sciences, Department of Biochemistry, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil; (M.M.K.); (A.A.d.S.); (L.G.K.); (F.G.)
- Laboratório Nacional de Energia e Geologia, I.P., Unidade de Bioenergia, Estrada do Paço do Lumiar 22, 1649-038 Lisboa, Portugal; (M.J.L.); (C.F.)
- ITQB NOVA, Instituto de Tecnologia Química e Biológica António Xavier, Av. da República, 2780-157 Oeiras, Portugal
| | - Angela A. dos Santos
- Center of Biological Sciences, Department of Biochemistry, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil; (M.M.K.); (A.A.d.S.); (L.G.K.); (F.G.)
| | - Leonardo G. Kretzer
- Center of Biological Sciences, Department of Biochemistry, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil; (M.M.K.); (A.A.d.S.); (L.G.K.); (F.G.)
| | - Fernanda Gelsleichter
- Center of Biological Sciences, Department of Biochemistry, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil; (M.M.K.); (A.A.d.S.); (L.G.K.); (F.G.)
| | - Maria José Leandro
- Laboratório Nacional de Energia e Geologia, I.P., Unidade de Bioenergia, Estrada do Paço do Lumiar 22, 1649-038 Lisboa, Portugal; (M.J.L.); (C.F.)
- ITQB NOVA, Instituto de Tecnologia Química e Biológica António Xavier, Av. da República, 2780-157 Oeiras, Portugal
| | - César Fonseca
- Laboratório Nacional de Energia e Geologia, I.P., Unidade de Bioenergia, Estrada do Paço do Lumiar 22, 1649-038 Lisboa, Portugal; (M.J.L.); (C.F.)
- Discovery, R&D, Chr. Hansen A/S, 2970 Hørsholm, Denmark
| | - Boris U. Stambuk
- Center of Biological Sciences, Department of Biochemistry, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil; (M.M.K.); (A.A.d.S.); (L.G.K.); (F.G.)
- Correspondence: ; Tel.: +55-48-3721-4449
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Pereira IDO, Dos Santos ÂA, Gonçalves DL, Purificação M, Guimarães NC, Tramontina R, Coutouné N, Zanella E, Matsushika A, Stambuk BU, Ienczak JL. Comparison of Spathaspora passalidarum and recombinant Saccharomyces cerevisiae for integration of first- and second-generation ethanol production. FEMS Yeast Res 2021; 21:6363686. [PMID: 34477865 DOI: 10.1093/femsyr/foab048] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 09/01/2021] [Indexed: 12/23/2022] Open
Abstract
First-generation ethanol (E1G) is based on the fermentation of sugars released from saccharine or starch sources, while second-generation ethanol (E2G) is focused on the fermentation of sugars released from lignocellulosic feedstocks. During the fractionation process to release sugars from hemicelluloses (mainly xylose), some inhibitor compounds are released hindering fermentation. Thus, the biggest challenge of using hemicellulosic hydrolysate is selecting strains and processes able to efficiently ferment xylose and tolerate inhibitors. With the aim of diluting inhibitors, sugarcane molasses (80% of sucrose content) can be mixed to hemicellulosic hydrolysate in an integrated E1G-E2G process. Cofermentations of xylose and sucrose were evaluated for the native xylose consumer Spathaspora passalidarum and a recombinant Saccharomyces cerevisiae strain. The industrial S. cerevisiae strain CAT-1 was modified to overexpress the XYL1, XYL2 and XKS1 genes and a mutant ([4-59Δ]HXT1) version of the low-affinity HXT1 permease, generating strain MP-C5H1. Although S. passalidarum showed better results for xylose fermentation, this yeast showed intracellular sucrose hydrolysis and low sucrose consumption in microaerobic conditions. Recombinant S. cerevisiae showed the best performance for cofermentation, and a batch strategy at high cell density in bioreactor achieved unprecedented results of ethanol yield, titer and volumetric productivity in E1G-E2G production process.
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Affiliation(s)
- Isabela de Oliveira Pereira
- Department of Chemical Engineering and Food Engineering, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
| | - Ângela Alves Dos Santos
- Department of Biochemistry, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
| | - Davi L Gonçalves
- Department of Biochemistry, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
| | - Marcela Purificação
- Department of Biochemistry, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
| | - Nick Candiotto Guimarães
- Department of Chemical Engineering and Food Engineering, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
| | - Robson Tramontina
- Graduate Program in Biosciences and Technology of Bioactive Products, Institute of Biology, State University of Campinas (UNICAMP), Campinas, SP 13083-852, Brazil.,Brazilian Biorenewable Laboratory, National Center for Research in Energy and Materials, Campinas, SP 13083-100, Brazil
| | - Natalia Coutouné
- Brazilian Biorenewable Laboratory, National Center for Research in Energy and Materials, Campinas, SP 13083-100, Brazil.,Graduate Program in Genetics and Molecular Biology, Institute of Biology, State University of Campinas (UNICAMP), Campinas, SP 13083-852, Brazil
| | - Eduardo Zanella
- Department of Biochemistry, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
| | - Akinori Matsushika
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology, Higashi-Hiroshima, Hiroshima 739-0046, Japan.,Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8530, Japan
| | - Boris U Stambuk
- Department of Biochemistry, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
| | - Jaciane Lutz Ienczak
- Department of Chemical Engineering and Food Engineering, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
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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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Bueno JGR, Borelli G, Corrêa TLR, Fiamenghi MB, José J, de Carvalho M, de Oliveira LC, Pereira GAG, dos Santos LV. Novel xylose transporter Cs4130 expands the sugar uptake repertoire in recombinant Saccharomyces cerevisiae strains at high xylose concentrations. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:145. [PMID: 32818042 PMCID: PMC7427733 DOI: 10.1186/s13068-020-01782-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/04/2020] [Indexed: 06/01/2023]
Abstract
BACKGROUND The need to restructure the world's energy matrix based on fossil fuels and mitigate greenhouse gas emissions stimulated the development of new biobased technologies for renewable energy. One promising and cleaner alternative is the use of second-generation (2G) fuels, produced from lignocellulosic biomass sugars. A major challenge on 2G technologies establishment is the inefficient assimilation of the five-carbon sugar xylose by engineered Saccharomyces cerevisiae strains, increasing fermentation time. The uptake of xylose across the plasma membrane is a critical limiting step and the budding yeast S. cerevisiae is not designed with a broad transport system and regulatory mechanisms to assimilate xylose in a wide range of concentrations present in 2G processes. RESULTS Assessing diverse microbiomes such as the digestive tract of plague insects and several decayed lignocellulosic biomasses, we isolated several yeast species capable of using xylose. Comparative fermentations selected the yeast Candida sojae as a potential source of high-affinity transporters. Comparative genomic analysis elects four potential xylose transporters whose properties were evaluated in the transporter null EBY.VW4000 strain carrying the xylose-utilizing pathway integrated into the genome. While the traditional xylose transporter Gxf1 allows an improved growth at lower concentrations (10 g/L), strains containing Cs3894 and Cs4130 show opposite responses with superior xylose uptake at higher concentrations (up to 50 g/L). Docking and normal mode analysis of Cs4130 and Gxf1 variants pointed out important residues related to xylose transport, identifying key differences regarding substrate translocation comparing both transporters. CONCLUSIONS Considering that xylose concentrations in second-generation hydrolysates can reach high values in several designed processes, Cs4130 is a promising novel candidate for xylose uptake. Here, we demonstrate a novel eukaryotic molecular transporter protein that improves growth at high xylose concentrations and can be used as a promising target towards engineering efficient pentose utilization in yeast.
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Affiliation(s)
- João Gabriel Ribeiro Bueno
- Brazilian Biorenewable National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, São Paulo 13083-100 Brazil
- Genetics and Molecular Biology Graduate Program, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Guilherme Borelli
- Genetics and Molecular Biology Graduate Program, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Thamy Lívia Ribeiro Corrêa
- Brazilian Biorenewable National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, São Paulo 13083-100 Brazil
| | - Mateus Bernabe Fiamenghi
- Genetics and Molecular Biology Graduate Program, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Juliana José
- Genetics and Molecular Biology Graduate Program, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Murilo de Carvalho
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Sao Paulo 13083-970 Brazil
- Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Sao Paulo 13083-970 Brazil
| | - Leandro Cristante de Oliveira
- Department of Physics-Institute of Biosciences, Humanities and Exact Sciences, UNESP, São Paulo State University, São José do Rio Preto, São Paulo 15054-000 Brazil
| | - Gonçalo A. G. Pereira
- Genetics and Molecular Biology Graduate Program, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Leandro Vieira dos Santos
- Brazilian Biorenewable National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, São Paulo 13083-100 Brazil
- Genetics and Molecular Biology Graduate Program, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
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8
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Jiang Y, Shen Y, Gu L, Wang Z, Su N, Niu K, Guo W, Hou S, Bao X, Tian C, Fang X. Identification and Characterization of an Efficient d-Xylose Transporter in Saccharomyces cerevisiae. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:2702-2710. [PMID: 32054270 DOI: 10.1021/acs.jafc.9b07113] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
d-Xylose is the most abundant hemicellulosic monomer on earth, but wild-type Saccharomyces cerevisiae has very limited d-xylose uptake capacity. We conducted bioprospecting for new sugar transporters from the d-xylose-consuming filamentous fungus Trichoderma reesei and identified three candidates belonging to the major facilitator superfamily. When they were expressed in yeast and assayed for d-xylose uptake, one of them, Xltr1p, had d-xylose transport activity that was more efficient than that of Gal2p, an endogenous yeast transporter. Site-directed mutagenesis was used to examine the functional contributions of 13 amino acid residues for the uptake of d-xylose, and these experiments identified particular amino acids that function distinctly in d-xylose vs glucose transport (e.g., F300). Excitingly, the yeast strain expressing the N326FXltr1p variant was able to carry a "high efficiency" transport for d-xylose but was nearly unable to utilize glucose; in contrast, the strain with the F300AXltr1p variant grew on glucose but lost d-xylose transport activity.
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Affiliation(s)
- Yi Jiang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
- College of Bioengineering, Qilu University of Technology, Jinan 250100, China
| | - Yu Shen
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Lichuan Gu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Zhenzhen Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Ning Su
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Kangle Niu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Wei Guo
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Shaoli Hou
- Yantai Huakangrongzan Biotechnology Co., Ltd, Yantai 264006, China
| | - Xiaoming Bao
- College of Bioengineering, Qilu University of Technology, Jinan 250100, China
| | - Chaoguang Tian
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
| | - Xu Fang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
- National Glycoengineering Research Center, Shandong University, Qingdao, Shandong 266237, China
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9
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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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10
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Feng Q, Liu ZL, Weber SA, Li S. Signature pathway expression of xylose utilization in the genetically engineered industrial yeast Saccharomyces cerevisiae. PLoS One 2018; 13:e0195633. [PMID: 29621349 PMCID: PMC5886582 DOI: 10.1371/journal.pone.0195633] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 03/25/2018] [Indexed: 01/18/2023] Open
Abstract
Haploid laboratory strains of Saccharomyces cerevisiae are commonly used for genetic engineering to enable their xylose utilization but little is known about the industrial yeast which is often recognized as diploid and as well as haploid and tetraploid. Here we report three unique signature pathway expression patterns and gene interactions in the centre metabolic pathways that signify xylose utilization of genetically engineered industrial yeast S. cerevisiae NRRL Y-50463, a diploid yeast. Quantitative expression analysis revealed outstanding high levels of constitutive expression of YXI, a synthesized yeast codon-optimized xylose isomerase gene integrated into chromosome XV of strain Y-50463. Comparative expression analysis indicated that the YXI was necessary to initiate the xylose metabolic pathway along with a set of heterologous xylose transporter and utilization facilitating genes including XUT4, XUT6, XKS1 and XYL2. The highly activated transketolase and transaldolase genes TKL1, TKL2, TAL1 and NQM1 as well as their complex interactions in the non-oxidative pentose phosphate pathway branch were critical for the serial of sugar transformation to drive the metabolic flow into glycolysis for increased ethanol production. The significantly increased expression of the entire PRS gene family facilitates functions of the life cycle and biosynthesis superpathway for the yeast. The outstanding higher levels of constitutive expression of YXI and the first insight into the signature pathway expression and the gene interactions in the closely related centre metabolic pathways from the industrial yeast aid continued efforts for development of the next-generation biocatalyst. Our results further suggest the industrial yeast is a desirable delivery vehicle for new strain development for efficient lignocellulose-to-advanced biofuels production.
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Affiliation(s)
- Quanzhou Feng
- Bioenergy Research Unit, US Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, Peoria, IL, United States of America
- Institute of New Energy Technology, Tsinghua University, Haidian Qu, Beijing, China
| | - Z. Lewis Liu
- Bioenergy Research Unit, US Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, Peoria, IL, United States of America
- USDA-MOST Joint Research Center for Biofuels, Peoria, IL, United States of America
- * E-mail: (ZLL); (SL)
| | - Scott A. Weber
- Bioenergy Research Unit, US Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, Peoria, IL, United States of America
| | - Shizhong Li
- Institute of New Energy Technology, Tsinghua University, Haidian Qu, Beijing, China
- USDA-MOST Joint Research Center for Biofuels, Peoria, IL, United States of America
- * E-mail: (ZLL); (SL)
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Xylose transport in yeast for lignocellulosic ethanol production: Current status. J Biosci Bioeng 2017; 125:259-267. [PMID: 29196106 DOI: 10.1016/j.jbiosc.2017.10.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 09/07/2017] [Accepted: 10/10/2017] [Indexed: 01/07/2023]
Abstract
Lignocellulosic ethanol has been considered as an alternative transportation fuel. Utilization of hemicellulosic fraction in lignocelluloses is crucial in economical production of lignocellulosic ethanol. However, this fraction has not efficiently been utilized by traditional yeast Saccharomyces cerevisiae. Genetically modified S. cerevisiae, which can utilize xylose, has several limitations including low ethanol yield, redox imbalance, and undesired metabolite formation similar to native xylose utilizing yeasts. Besides, xylose uptake is a major issue, where sugar transport system plays an important role. These genetically modified and wild-type yeast strains have further been engineered for improved xylose uptake. Various techniques have been employed to facilitate the xylose transportation in these strains. The present review is focused on the sugar transport machineries, mechanisms of xylose transport, limitations and how to deal with xylose transport for xylose assimilation in yeast cells. The recent advances in different techniques to facilitate the xylose transportation have also been discussed.
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Jansen MLA, Bracher JM, Papapetridis I, Verhoeven MD, de Bruijn H, de Waal PP, van Maris AJA, Klaassen P, Pronk JT. Saccharomyces cerevisiae strains for second-generation ethanol production: from academic exploration to industrial implementation. FEMS Yeast Res 2017; 17:3868933. [PMID: 28899031 PMCID: PMC5812533 DOI: 10.1093/femsyr/fox044] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 06/15/2017] [Indexed: 11/18/2022] Open
Abstract
The recent start-up of several full-scale 'second generation' ethanol plants marks a major milestone in the development of Saccharomyces cerevisiae strains for fermentation of lignocellulosic hydrolysates of agricultural residues and energy crops. After a discussion of the challenges that these novel industrial contexts impose on yeast strains, this minireview describes key metabolic engineering strategies that have been developed to address these challenges. Additionally, it outlines how proof-of-concept studies, often developed in academic settings, can be used for the development of robust strain platforms that meet the requirements for industrial application. Fermentation performance of current engineered industrial S. cerevisiae strains is no longer a bottleneck in efforts to achieve the projected outputs of the first large-scale second-generation ethanol plants. Academic and industrial yeast research will continue to strengthen the economic value position of second-generation ethanol production by further improving fermentation kinetics, product yield and cellular robustness under process conditions.
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Affiliation(s)
- Mickel L. A. Jansen
- DSM Biotechnology Centre, Alexander Fleminglaan 1, 2613 AX Delft, The
Netherlands
| | - Jasmine M. Bracher
- Department of Biotechnology, Delft University of Technology, Van der Maasweg
9, 2629 HZ Delft, The Netherlands
| | - Ioannis Papapetridis
- Department of Biotechnology, Delft University of Technology, Van der Maasweg
9, 2629 HZ Delft, The Netherlands
| | - Maarten D. Verhoeven
- Department of Biotechnology, Delft University of Technology, Van der Maasweg
9, 2629 HZ Delft, The Netherlands
| | - Hans de Bruijn
- DSM Biotechnology Centre, Alexander Fleminglaan 1, 2613 AX Delft, The
Netherlands
| | - Paul P. de Waal
- DSM Biotechnology Centre, Alexander Fleminglaan 1, 2613 AX Delft, The
Netherlands
| | - Antonius J. A. van Maris
- Department of Biotechnology, Delft University of Technology, Van der Maasweg
9, 2629 HZ Delft, The Netherlands
| | - Paul Klaassen
- DSM Biotechnology Centre, Alexander Fleminglaan 1, 2613 AX Delft, The
Netherlands
| | - Jack T. Pronk
- Department of Biotechnology, Delft University of Technology, Van der Maasweg
9, 2629 HZ Delft, The Netherlands
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Shin HY, Nijland JG, de Waal PP, Driessen AJM. The amino-terminal tail of Hxt11 confers membrane stability to the Hxt2 sugar transporter and improves xylose fermentation in the presence of acetic acid. Biotechnol Bioeng 2017; 114:1937-1945. [PMID: 28464256 PMCID: PMC5575463 DOI: 10.1002/bit.26322] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 04/05/2017] [Accepted: 04/27/2017] [Indexed: 12/12/2022]
Abstract
Hxt2 is a glucose repressed, high affinity glucose transporter of the yeast Saccharomyces cerevisiae and is subjected to high glucose induced degradation. Hxt11 is a sugar transporter that is stably expressed at the membrane irrespective the sugar concentration. To transfer this property to Hxt2, the N‐terminal tail of Hxt2 was replaced by the corresponding region of Hxt11 yielding a chimeric Hxt11/2 transporter. This resulted in the stable expression of Hxt2 at the membrane and improved the growth on 8% d‐glucose and 4% d‐xylose. Mutation of N361 of Hxt11/2 into threonine reversed the specificity for d‐xylose over d‐glucose with high d‐xylose transport rates. This mutant supported efficient sugar fermentation of both d‐glucose and d‐xylose at industrially relevant sugar concentrations even in the presence of the inhibitor acetic acid which is normally present in lignocellulosic hydrolysates. Biotechnol. Bioeng. 2017;114: 1937–1945. © 2017 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Hyun Yong Shin
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology, University of Groningen, Zernike Institute for Advanced Materials and Kluyver Centre for Genomics of Industrial Fermentation, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Jeroen G Nijland
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology, University of Groningen, Zernike Institute for Advanced Materials and Kluyver Centre for Genomics of Industrial Fermentation, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | | | - Arnold J M Driessen
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology, University of Groningen, Zernike Institute for Advanced Materials and Kluyver Centre for Genomics of Industrial Fermentation, Nijenborgh 7, 9747 AG Groningen, The Netherlands
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Metabolic engineering of a haploid strain derived from a triploid industrial yeast for producing cellulosic ethanol. Metab Eng 2017; 40:176-185. [DOI: 10.1016/j.ymben.2017.02.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 02/06/2017] [Accepted: 02/14/2017] [Indexed: 12/25/2022]
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Cadete RM, de las Heras AM, Sandström AG, Ferreira C, Gírio F, Gorwa-Grauslund MF, Rosa CA, Fonseca C. Exploring xylose metabolism in Spathaspora species: XYL1.2 from Spathaspora passalidarum as the key for efficient anaerobic xylose fermentation in metabolic engineered Saccharomyces cerevisiae. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:167. [PMID: 27499810 PMCID: PMC4974763 DOI: 10.1186/s13068-016-0570-6] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 07/12/2016] [Indexed: 05/21/2023]
Abstract
BACKGROUND The production of ethanol and other fuels and chemicals from lignocellulosic materials is dependent of efficient xylose conversion. Xylose fermentation capacity in yeasts is usually linked to xylose reductase (XR) accepting NADH as cofactor. The XR from Scheffersomyces stipitis, which is able to use NADH as cofactor but still prefers NADPH, has been used to generate recombinant xylose-fermenting Saccharomyces cerevisiae. Novel xylose-fermenting yeasts species, as those from the Spathaspora clade, have been described and are potential sources of novel genes to improve xylose fermentation in S. cerevisiae. RESULTS Xylose fermentation by six strains from different Spathaspora species isolated in Brazil, plus the Sp. passalidarum type strain (CBS 10155(T)), was characterized under two oxygen-limited conditions. The best xylose-fermenting strains belong to the Sp. passalidarum species, and their highest ethanol titers, yields, and productivities were correlated to higher XR activity with NADH than with NADPH. Among the different Spathaspora species, Sp. passalidarum appears to be the sole harboring two XYL1 genes: XYL1.1, similar to the XYL1 found in other Spathaspora and yeast species and XYL1.2, with relatively higher expression level. XYL1.1p and XYL1.2p from Sp. passalidarum were expressed in S. cerevisiae TMB 3044 and XYL1.1p was confirmed to be strictly NADPH-dependent, while XYL1.2p to use both NADPH and NADH, with higher activity with the later. Recombinant S. cerevisiae strains expressing XYL1.1p did not show anaerobic growth in xylose medium. Under anaerobic xylose fermentation, S. cerevisiae TMB 3504, which expresses XYL1.2p from Sp. passalidarum, revealed significant higher ethanol yield and productivity than S. cerevisiae TMB 3422, which harbors XYL1p N272D from Sc. stipitis in the same isogenic background (0.40 vs 0.34 g gCDW (-1) and 0.33 vs 0.18 g gCDW (-1) h(-1), respectively). CONCLUSION This work explored a new clade of xylose-fermenting yeasts (Spathaspora species) towards the engineering of S. cerevisiae for improved xylose fermentation. The new S. cerevisiae TMB 3504 displays higher XR activity with NADH than with NADPH, with consequent improved ethanol yield and productivity and low xylitol production. This meaningful advance in anaerobic xylose fermentation by recombinant S. cerevisiae (using the XR/XDH pathway) paves the way for the development of novel industrial pentose-fermenting strains.
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Affiliation(s)
- Raquel M. Cadete
- Departamento de Microbiologia, ICB, C.P. 486, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais 31270-901 Brazil
- Laboratório Nacional de Energia e Geologia, I.P., Unidade de Bioenergia, Estrada do Paço do Lumiar 22, 1649-038 Lisbon, Portugal
- Department of Applied Microbiology, Lund University, PO Box 124, 22100 Lund, Sweden
| | | | - Anders G. Sandström
- Department of Applied Microbiology, Lund University, PO Box 124, 22100 Lund, Sweden
- Novozymes A/S, Krogshøjvej 36, 2880 Bagsværd, Denmark
| | - Carla Ferreira
- Laboratório Nacional de Energia e Geologia, I.P., Unidade de Bioenergia, Estrada do Paço do Lumiar 22, 1649-038 Lisbon, Portugal
| | - Francisco Gírio
- Laboratório Nacional de Energia e Geologia, I.P., Unidade de Bioenergia, Estrada do Paço do Lumiar 22, 1649-038 Lisbon, Portugal
| | | | - Carlos A. Rosa
- Departamento de Microbiologia, ICB, C.P. 486, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais 31270-901 Brazil
| | - César Fonseca
- Laboratório Nacional de Energia e Geologia, I.P., Unidade de Bioenergia, Estrada do Paço do Lumiar 22, 1649-038 Lisbon, Portugal
- Section for Sustainable Biotechnology, Aalborg University Copenhagen, A. C. Meyers Vænge 15, 2450 Copenhagen SV, Denmark
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Reznicek O, Facey S, de Waal P, Teunissen A, de Bont J, Nijland J, Driessen A, Hauer B. Improved xylose uptake in Saccharomyces cerevisiae
due to directed evolution of galactose permease Gal2 for sugar co-consumption. J Appl Microbiol 2015; 119:99-111. [DOI: 10.1111/jam.12825] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 04/01/2015] [Accepted: 04/08/2015] [Indexed: 12/19/2022]
Affiliation(s)
- O. Reznicek
- Institute of Technical Biochemistry; University of Stuttgart; Stuttgart Germany
| | - S.J. Facey
- Institute of Technical Biochemistry; University of Stuttgart; Stuttgart Germany
| | | | | | | | - J.G. Nijland
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology; Zernike Institute for Advanced Materials and Kluyver Centre for Genomics of Industrial Fermentation; University of Groningen; Groningen The Netherlands
| | - A.J.M. Driessen
- Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology; Zernike Institute for Advanced Materials and Kluyver Centre for Genomics of Industrial Fermentation; University of Groningen; Groningen The Netherlands
| | - B. Hauer
- Institute of Technical Biochemistry; University of Stuttgart; Stuttgart Germany
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Romaní A, Pereira F, Johansson B, Domingues L. Metabolic engineering of Saccharomyces cerevisiae ethanol strains PE-2 and CAT-1 for efficient lignocellulosic fermentation. BIORESOURCE TECHNOLOGY 2015; 179:150-158. [PMID: 25536512 DOI: 10.1016/j.biortech.2014.12.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 12/05/2014] [Accepted: 12/07/2014] [Indexed: 05/08/2023]
Abstract
In this work, Saccharomyces cerevisiae strains PE-2 and CAT-1, commonly used in the Brazilian fuel ethanol industry, were engineered for xylose fermentation, where the first fermented xylose faster than the latter, but also produced considerable amounts of xylitol. An engineered PE-2 strain (MEC1121) efficiently consumed xylose in presence of inhibitors both in synthetic and corn-cob hydrolysates. Interestingly, the S. cerevisiae MEC1121 consumed xylose and glucose simultaneously, while a CEN.PK based strain consumed glucose and xylose sequentially. Deletion of the aldose reductase GRE3 lowered xylitol production to undetectable levels and increased xylose consumption rate which led to higher final ethanol concentrations. Fermentation of corn-cob hydrolysate using this strain, MEC1133, resulted in an ethanol yield of 0.47 g/g of total sugars which is 92% of the theoretical yield.
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Affiliation(s)
- Aloia Romaní
- CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal.
| | - Filipa Pereira
- CBMA - Center of Molecular and Environmental Biology, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal.
| | - Björn Johansson
- CBMA - Center of Molecular and Environmental Biology, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal.
| | - Lucília Domingues
- CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal.
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Kahar P, Tanaka S. A xylose-fermenting yeast hybridized by intergeneric fusion between Saccharomyces cerevisiae and Candida intermediamutants for ethanol production. ACTA ACUST UNITED AC 2014. [DOI: 10.1186/s40508-014-0017-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Lara CA, Santos RO, Cadete RM, Ferreira C, Marques S, Gírio F, Oliveira ES, Rosa CA, Fonseca C. Identification and characterisation of xylanolytic yeasts isolated from decaying wood and sugarcane bagasse in Brazil. Antonie van Leeuwenhoek 2014; 105:1107-19. [PMID: 24748334 DOI: 10.1007/s10482-014-0172-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 04/04/2014] [Indexed: 11/28/2022]
Abstract
In this study, yeasts associated with lignocellulosic materials in Brazil, including decaying wood and sugarcane bagasse, were isolated, and their ability to produce xylanolytic enzymes was investigated. A total of 358 yeast isolates were obtained, with 198 strains isolated from decaying wood and 160 strains isolated from decaying sugarcane bagasse samples. Seventy-five isolates possessed xylanase activity in solid medium and were identified as belonging to nine species: Candida intermedia, C. tropicalis, Meyerozyma guilliermondii, Scheffersomyces shehatae, Sugiyamaella smithiae, Cryptococcus diffluens, Cr. heveanensis, Cr. laurentii and Trichosporon mycotoxinivorans. Twenty-one isolates were further screened for total xylanase activity in liquid medium with xylan, and five xylanolytic yeasts were selected for further characterization, which included quantitative analysis of growth in xylan and xylose and xylanase and β-D-xylosidase activities. The yeasts showing the highest growth rate and cell density in xylan, Cr. laurentii UFMG-HB-48, Su. smithiae UFMG-HM-80.1 and Sc. shehatae UFMG-HM-9.1a, were, simultaneously, those exhibiting higher xylanase activity. Xylan induced the highest level of (extracellular) xylanase activity in Cr. laurentii UFMG-HB-48 and the highest level of (intracellular, extracellular and membrane-associated) β-D-xylosidase activity in Su. smithiae UFMG-HM-80.1. Also, significant β-D-xylosidase levels were detected in xylan-induced cultures of Cr. laurentii UFMG-HB-48 and Sc. shehatae UFMG-HM-9.1a, mainly in extracellular and intracellular spaces, respectively. Under xylose induction, Cr. laurentii UFMG-HB-48 showed the highest intracellular β-D-xylosidase activity among all the yeast tested. C. tropicalis UFMG-HB 93a showed its higher (intracellular) β-D-xylosidase activity under xylose induction and higher at 30 °C than at 50 °C. This study revealed different xylanolytic abilities and strategies in yeasts to metabolise xylan and/or its hydrolysis products (xylo-oligosaccharides and xylose). Xylanolytic yeasts are able to secrete xylanolytic enzymes mainly when induced by xylan and present different strategies (intra- and/or extracellular hydrolysis) for the metabolism of xylo-oligosaccharides. Some of the unique xylanolytic traits identified here should be further explored for their applicability in specific biotechnological processes.
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Affiliation(s)
- Carla A Lara
- Departamento de Alimentos, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, 31270-901, Brazil
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Li J, Lin L, Li H, Tian C, Ma Y. Transcriptional comparison of the filamentous fungus Neurospora crassa growing on three major monosaccharides D-glucose, D-xylose and L-arabinose. BIOTECHNOLOGY FOR BIOFUELS 2014; 7:31. [PMID: 24581151 PMCID: PMC4015282 DOI: 10.1186/1754-6834-7-31] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 02/14/2014] [Indexed: 05/09/2023]
Abstract
BACKGROUND D-glucose, D-xylose and L-arabinose are the three major monosaccharides in plant cell walls. Complete utilization of all three sugars is still a bottleneck for second-generation cellulolytic bioethanol production, especially for L-arabinose. However, little is known about gene expression profiles during L-arabinose utilization in fungi and a comparison of the genome-wide fungal response to these three major monosaccharides has not yet been reported. RESULTS Using next-generation sequencing technology, we have analyzed the transcriptome of N. crassa grown on L-arabinose versus D-xylose, with D-glucose as the reference. We found that the gene expression profiles on L-arabinose were dramatically different from those on D-xylose. It appears that L-arabinose can rewire the fungal cell metabolic pathway widely and provoke the expression of many kinds of sugar transporters, hemicellulase genes and transcription factors. In contrast, many fewer genes, mainly related to the pentose metabolic pathway, were upregulated on D-xylose. The rewired metabolic response to L-arabinose was significantly different and wider than that under no carbon conditions, although the carbon starvation response was initiated on L-arabinose. Three novel sugar transporters were identified and characterized for their substrates here, including one glucose transporter GLT-1 (NCU01633) and two novel pentose transporters, XAT-1 (NCU01132), XYT-1 (NCU05627). One transcription factor associated with the regulation of hemicellulase genes, HCR-1 (NCU05064) was also characterized in the present study. CONCLUSIONS We conducted the first transcriptome analysis of Neurospora crassa grown on L-arabinose and performed a comparative analysis with cells grown on D-xylose and D-glucose, which deepens the understanding of the utilization of L-arabinose and D-xylose in filamentous fungi. The dataset generated by this research will be useful for mining target genes for D-xylose and L-arabinose utilization engineering and the novel sugar transportes identified are good targets for pentose untilization and biofuels production. Moreover, hemicellulase production by fungi could be improved by modifying the hemicellulase regulator discovered here.
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Affiliation(s)
- Jingen Li
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Liangcai Lin
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
| | - Huiyan Li
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
| | - Chaoguang Tian
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
| | - Yanhe Ma
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
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Nielsen J, Larsson C, van Maris A, Pronk J. Metabolic engineering of yeast for production of fuels and chemicals. Curr Opin Biotechnol 2013; 24:398-404. [DOI: 10.1016/j.copbio.2013.03.023] [Citation(s) in RCA: 235] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 03/18/2013] [Accepted: 03/27/2013] [Indexed: 01/01/2023]
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Glucose and xylose co-fermentation of pretreated wheat straw using mutants of S. cerevisiae TMB3400. J Biotechnol 2013; 164:50-8. [DOI: 10.1016/j.jbiotec.2012.12.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 11/27/2012] [Accepted: 12/10/2012] [Indexed: 11/18/2022]
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Romero A, Mateo J, Maicas S. Characterization of an ethanol-tolerant 1,4-β-xylosidase produced byPichia membranifaciens. Lett Appl Microbiol 2012; 55:354-61. [DOI: 10.1111/j.1472-765x.2012.03297.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Cofermentation of glucose, xylose, and cellobiose by the beetle-associated yeast Spathaspora passalidarum. Appl Environ Microbiol 2012; 78:5492-500. [PMID: 22636012 DOI: 10.1128/aem.00374-12] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fermentation of cellulosic and hemicellulosic sugars from biomass could resolve food-versus-fuel conflicts inherent in the bioconversion of grains. However, the inability to coferment glucose and xylose is a major challenge to the economical use of lignocellulose as a feedstock. Simultaneous cofermentation of glucose, xylose, and cellobiose is problematic for most microbes because glucose represses utilization of the other saccharides. Surprisingly, the ascomycetous, beetle-associated yeast Spathaspora passalidarum, which ferments xylose and cellobiose natively, can also coferment these two sugars in the presence of 30 g/liter glucose. S. passalidarum simultaneously assimilates glucose and xylose aerobically, it simultaneously coferments glucose, cellobiose, and xylose with an ethanol yield of 0.42 g/g, and it has a specific ethanol production rate on xylose more than 3 times that of the corresponding rate on glucose. Moreover, an adapted strain of S. passalidarum produced 39 g/liter ethanol with a yield of 0.37 g/g sugars from a hardwood hydrolysate. Metabolome analysis of S. passalidarum before onset and during the fermentations of glucose and xylose showed that the flux of glycolytic intermediates is significantly higher on xylose than on glucose. The high affinity of its xylose reductase activities for NADH and xylose combined with allosteric activation of glycolysis probably accounts in part for its unusual capacities. These features make S. passalidarum very attractive for studying regulatory mechanisms enabling bioconversion of lignocellulosic materials by yeasts.
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Bergdahl B, Heer D, Sauer U, Hahn-Hägerdal B, van Niel EWJ. Dynamic metabolomics differentiates between carbon and energy starvation in recombinant Saccharomyces cerevisiae fermenting xylose. BIOTECHNOLOGY FOR BIOFUELS 2012; 5:34. [PMID: 22587303 PMCID: PMC3462113 DOI: 10.1186/1754-6834-5-34] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Accepted: 04/23/2012] [Indexed: 05/15/2023]
Abstract
BACKGROUND The concerted effects of changes in gene expression due to changes in the environment are ultimately reflected in the metabolome. Dynamics of metabolite concentrations under a certain condition can therefore give a description of the cellular state with a high degree of functional information. We used this potential to evaluate the metabolic status of two recombinant strains of Saccharomyces cerevisiae during anaerobic batch fermentation of a glucose/xylose mixture. Two isogenic strains were studied, differing only in the pathways used for xylose assimilation: the oxidoreductive pathway with xylose reductase (XR) and xylitol dehydrogenase (XDH) or the isomerization pathway with xylose isomerase (XI). The isogenic relationship between the two strains ascertains that the observed responses are a result of the particular xylose pathway and not due to unknown changes in regulatory systems. An increased understanding of the physiological state of these strains is important for further development of efficient pentose-utilizing strains for bioethanol production. RESULTS Using LC-MS/MS we determined the dynamics in the concentrations of intracellular metabolites in central carbon metabolism, nine amino acids, the purine nucleotides and redox cofactors. The general response to the transition from glucose to xylose was increased concentrations of amino acids and TCA-cycle intermediates, and decreased concentrations of sugar phosphates and redox cofactors. The two strains investigated had significantly different uptake rates of xylose which led to an enhanced response in the XI-strain. Despite the difference in xylose uptake rate, the adenylate energy charge remained high and stable around 0.8 in both strains. In contrast to the adenylate pool, large changes were observed in the guanylate pool. CONCLUSIONS The low uptake of xylose by the XI-strain led to several distinguished responses: depletion of key metabolites in glycolysis and NADPH, a reduced GTP/GDP ratio and accumulation of PEP and aromatic amino acids. These changes are strong indicators of carbon starvation. The XR/XDH-strain displayed few such traits. The coexistence of these traits and a stable adenylate charge indicates that xylose supplies energy to the cells but does not suppress a response similar to carbon starvation. Particular signals may play a role in the latter, of which the GTP/GMP ratio could be a candidate as it decreased significantly in both strains.
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Affiliation(s)
- Basti Bergdahl
- Applied Microbiology, Lund University, PO Box 124, SE-221 00, Lund, Sweden
| | | | - Uwe Sauer
- ETH Zurich, Zurich, 8093, Switzerland
| | | | - Ed WJ van Niel
- Applied Microbiology, Lund University, PO Box 124, SE-221 00, Lund, Sweden
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