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Barros KO, Mader M, Krause DJ, Pangilinan J, Andreopoulos B, Lipzen A, Mondo SJ, Grigoriev IV, Rosa CA, Sato TK, Hittinger CT. Oxygenation influences xylose fermentation and gene expression in the yeast genera Spathaspora and Scheffersomyces. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:20. [PMID: 38321504 PMCID: PMC10848558 DOI: 10.1186/s13068-024-02467-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 01/28/2024] [Indexed: 02/08/2024]
Abstract
BACKGROUND Cost-effective production of biofuels from lignocellulose requires the fermentation of D-xylose. Many yeast species within and closely related to the genera Spathaspora and Scheffersomyces (both of the order Serinales) natively assimilate and ferment xylose. Other species consume xylose inefficiently, leading to extracellular accumulation of xylitol. Xylitol excretion is thought to be due to the different cofactor requirements of the first two steps of xylose metabolism. Xylose reductase (XR) generally uses NADPH to reduce xylose to xylitol, while xylitol dehydrogenase (XDH) generally uses NAD+ to oxidize xylitol to xylulose, creating an imbalanced redox pathway. This imbalance is thought to be particularly consequential in hypoxic or anoxic environments. RESULTS We screened the growth of xylose-fermenting yeast species in high and moderate aeration and identified both ethanol producers and xylitol producers. Selected species were further characterized for their XR and XDH cofactor preferences by enzyme assays and gene expression patterns by RNA-Seq. Our data revealed that xylose metabolism is more redox balanced in some species, but it is strongly affected by oxygen levels. Under high aeration, most species switched from ethanol production to xylitol accumulation, despite the availability of ample oxygen to accept electrons from NADH. This switch was followed by decreases in enzyme activity and the expression of genes related to xylose metabolism, suggesting that bottlenecks in xylose fermentation are not always due to cofactor preferences. Finally, we expressed XYL genes from multiple Scheffersomyces species in a strain of Saccharomyces cerevisiae. Recombinant S. cerevisiae expressing XYL1 from Scheffersomyces xylosifermentans, which encodes an XR without a cofactor preference, showed improved anaerobic growth on xylose as the primary carbon source compared to S. cerevisiae strain expressing XYL genes from Scheffersomyces stipitis. CONCLUSION Collectively, our data do not support the hypothesis that xylitol accumulation occurs primarily due to differences in cofactor preferences between xylose reductase and xylitol dehydrogenase; instead, gene expression plays a major role in response to oxygen levels. We have also identified the yeast Sc. xylosifermentans as a potential source for genes that can be engineered into S. cerevisiae to improve xylose fermentation and biofuel production.
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Affiliation(s)
- Katharina O Barros
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA
- Laboratory of Genetics, Wisconsin Energy Institute, J. F. Crow Institute for the Study of Evolution, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI, USA
- Departamento de Microbiologia, ICB, C.P. 486, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Megan Mader
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA
| | - David J Krause
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA
- Laboratory of Genetics, Wisconsin Energy Institute, J. F. Crow Institute for the Study of Evolution, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI, USA
| | - Jasmyn Pangilinan
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Bill Andreopoulos
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Computer Science, San Jose State University, One Washington Square, San Jose, CA, USA
| | - Anna Lipzen
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Stephen J Mondo
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Agricultural Biology, Colorado State University, Fort Collins, CO, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Igor V Grigoriev
- U.S. Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Plant and Microbial Department, University of California Berkeley, Berkeley, CA, USA
| | - Carlos A Rosa
- Departamento de Microbiologia, ICB, C.P. 486, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Trey K Sato
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA.
| | - Chris Todd Hittinger
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA.
- Laboratory of Genetics, Wisconsin Energy Institute, J. F. Crow Institute for the Study of Evolution, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI, USA.
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2
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Fiamenghi MB, Prodonoff JS, Borelli G, Carazzolle MF, Pereira GAG, José J. Comparative genomics reveals probable adaptations for xylose use in Thermoanaerobacterium saccharolyticum. Extremophiles 2024; 28:9. [PMID: 38190047 DOI: 10.1007/s00792-023-01327-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 11/28/2023] [Indexed: 01/09/2024]
Abstract
Second-generation ethanol, a promising biofuel for reducing greenhouse gas emissions, faces challenges due to the inefficient metabolism of xylose, a pentose sugar. Overcoming this hurdle requires exploration of genes, pathways, and organisms capable of fermenting xylose. Thermoanaerobacterium saccharolyticum is an organism capable of naturally fermenting compounds of industrial interest, such as xylose, and understanding evolutionary adaptations may help to bring novel genes and information that can be used for industrial yeast, increasing production of current bio-platforms. This study presents a deep evolutionary study of members of the firmicutes clade, focusing on adaptations in Thermoanaerobacterium saccharolyticum that may be related to overall fermentation metabolism, especially for xylose fermentation. One highlight is the finding of positive selection on a xylose-binding protein of the xylFGH operon, close to the annotated sugar binding site, with this protein already being found to be expressed in xylose fermenting conditions in a previous study. Results from this study can serve as basis for searching for candidate genes to use in industrial strains or to improve Thermoanaerobacterium saccharolyticum as a new microbial cell factory, which may help to solve current problems found in the biofuels' industry.
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Affiliation(s)
- Mateus Bernabe Fiamenghi
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - Juliana Silveira Prodonoff
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - Guilherme Borelli
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - Marcelo Falsarella Carazzolle
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - Gonçalo Amarante Guimaraes Pereira
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil.
| | - Juliana José
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
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3
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Nalabothu RL, Fisher KJ, LaBella AL, Meyer TA, Opulente DA, Wolters JF, Rokas A, Hittinger CT. Codon Optimization Improves the Prediction of Xylose Metabolism from Gene Content in Budding Yeasts. Mol Biol Evol 2023; 40:msad111. [PMID: 37154525 PMCID: PMC10263009 DOI: 10.1093/molbev/msad111] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 02/28/2023] [Accepted: 05/04/2023] [Indexed: 05/10/2023] Open
Abstract
Xylose is the second most abundant monomeric sugar in plant biomass. Consequently, xylose catabolism is an ecologically important trait for saprotrophic organisms, as well as a fundamentally important trait for industries that hope to convert plant mass to renewable fuels and other bioproducts using microbial metabolism. Although common across fungi, xylose catabolism is rare within Saccharomycotina, the subphylum that contains most industrially relevant fermentative yeast species. The genomes of several yeasts unable to consume xylose have been previously reported to contain the full set of genes in the XYL pathway, suggesting the absence of a gene-trait correlation for xylose metabolism. Here, we measured growth on xylose and systematically identified XYL pathway orthologs across the genomes of 332 budding yeast species. Although the XYL pathway coevolved with xylose metabolism, we found that pathway presence only predicted xylose catabolism about half of the time, demonstrating that a complete XYL pathway is necessary, but not sufficient, for xylose catabolism. We also found that XYL1 copy number was positively correlated, after phylogenetic correction, with xylose utilization. We then quantified codon usage bias of XYL genes and found that XYL3 codon optimization was significantly higher, after phylogenetic correction, in species able to consume xylose. Finally, we showed that codon optimization of XYL2 was positively correlated, after phylogenetic correction, with growth rates in xylose medium. We conclude that gene content alone is a weak predictor of xylose metabolism and that using codon optimization enhances the prediction of xylose metabolism from yeast genome sequence data.
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Affiliation(s)
- Rishitha L Nalabothu
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI
| | - Kaitlin J Fisher
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- Department of Biological Sciences, State University of New York at Oswego, Oswego, NY
| | - Abigail Leavitt LaBella
- Department of Biological Sciences, Vanderbilt University, Nashville, TN
- Evolutionary Studies Initiative, Vanderbilt University, Nashville, TN
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, NC
| | - Taylor A Meyer
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI
| | - Dana A Opulente
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI
- Department of Biology, Villanova University, Villanova, PA
| | - John F Wolters
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Nashville, TN
- Evolutionary Studies Initiative, Vanderbilt University, Nashville, TN
| | - Chris Todd Hittinger
- Laboratory of Genetics, J. F. Crow Institute for the Study of Evolution, Wisconsin Energy Institute, Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI
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4
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Galhardo JP, Piffer AP, Fiamenghi MB, Borelli G, da Silva DRM, Vasconcelos AA, Carazzolle MF, Pereira GAG, José J. Wide distribution of D-xylose dehydrogenase in yeasts reveals a new element in the D-xylose metabolism for bioethanol production. FEMS Yeast Res 2023; 23:foad003. [PMID: 36731871 DOI: 10.1093/femsyr/foad003] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 01/03/2023] [Accepted: 02/01/2023] [Indexed: 02/04/2023] Open
Abstract
D-xylose utilization by yeasts is an essential feature for improving second-generation ethanol production. However, industrial yeast strains are incapable of consuming D-xylose. Previous analyzes of D-xylose-consuming or fermenting yeast species reveal that the genomic features associated with this phenotype are complex and still not fully understood. Here we present a previously neglected yeast enzyme related to D-xylose metabolism, D-xylose dehydrogenase (XylDH), which is found in at least 105 yeast genomes. By analyzing the XylDH gene family, we brought evidence of gene evolution marked by purifying selection on codons and positive selection evidence in D-xylose-consuming and fermenting species, suggesting the importance of XylDH for D-xylose-related phenotypes in yeasts. Furthermore, although we found no putative metabolic pathway for XylDH in yeast genomes, namely the absence of three bacterial known pathways for this enzyme, we also provide its expression profile on D-xylose media following D-xylose reductase for two yeasts with publicly available transcriptomes. Based on these results, we suggest that XylDH plays an important role in D-xylose usage by yeasts, likely being involved in a cofactor regeneration system by reducing cofactor imbalance in the D-xylose reductase pathway.
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Affiliation(s)
- Juliana P Galhardo
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - André P Piffer
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - Mateus B Fiamenghi
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - Guilherme Borelli
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - Duguay R M da Silva
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - Adrielle A Vasconcelos
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - Marcelo F Carazzolle
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - Gonçalo A G Pereira
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
| | - Juliana José
- Laboratory of Genomics and bioEnergy (LGE), Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, UNICAMP, Campinas, São Paulo, Brazil
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5
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Fiamenghi MB, Bueno JGR, Camargo AP, Borelli G, Carazzolle MF, Pereira GAG, dos Santos LV, José J. Machine learning and comparative genomics approaches for the discovery of xylose transporters in yeast. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:57. [PMID: 35596177 PMCID: PMC9123741 DOI: 10.1186/s13068-022-02153-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 05/05/2022] [Indexed: 11/15/2022]
Abstract
Background The need to mitigate and substitute the use of fossil fuels as the main energy matrix has led to the study and development of biofuels as an alternative. Second-generation (2G) ethanol arises as one biofuel with great potential, due to not only maintaining food security, but also as a product from economically interesting crops such as energy-cane. One of the main challenges of 2G ethanol is the inefficient uptake of pentose sugars by industrial yeast Saccharomyces cerevisiae, the main organism used for ethanol production. Understanding the main drivers for xylose assimilation and identify novel and efficient transporters is a key step to make the 2G process economically viable. Results By implementing a strategy of searching for present motifs that may be responsible for xylose transport and past adaptations of sugar transporters in xylose fermenting species, we obtained a classifying model which was successfully used to select four different candidate transporters for evaluation in the S. cerevisiae hxt-null strain, EBY.VW4000, harbouring the xylose consumption pathway. Yeast cells expressing the transporters SpX, SpH and SpG showed a superior uptake performance in xylose compared to traditional literature control Gxf1. Conclusions Modelling xylose transport with the small data available for yeast and bacteria proved a challenge that was overcome through different statistical strategies. Through this strategy, we present four novel xylose transporters which expands the repertoire of candidates targeting yeast genetic engineering for industrial fermentation. The repeated use of the model for characterizing new transporters will be useful both into finding the best candidates for industrial utilization and to increase the model’s predictive capabilities. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13068-022-02153-7.
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6
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Sanya DRA, Onésime D, Passoth V, Maiti MK, Chattopadhyay A, Khot MB. Yeasts of the Blastobotrys genus are promising platform for lipid-based fuels and oleochemicals production. Appl Microbiol Biotechnol 2021; 105:4879-4897. [PMID: 34110474 DOI: 10.1007/s00253-021-11354-3] [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: 02/18/2021] [Revised: 04/29/2021] [Accepted: 05/16/2021] [Indexed: 12/31/2022]
Abstract
Strains of the yeast genus Blastobotrys (subphylum Saccharomycotina) represent a valuable biotechnological resource for basic biochemistry research, single-cell protein, and heterologous protein production processes. Species of this genus are dimorphic, non-pathogenic, thermotolerant, and can assimilate a variety of hydrophilic and hydrophobic substrates. These can constitute a single-cell oil platform in an emerging bio-based economy as oleaginous traits have been discovered recently. However, the regulatory network of lipogenesis in these yeasts is poorly understood. To keep pace with the growing market demands for lipid-derived products, it is critical to understand the lipid biosynthesis in these unconventional yeasts to pinpoint what governs the preferential channelling of carbon flux into lipids instead of the competing pathways. This review summarizes information relevant to the regulation of lipid metabolic pathways and prospects of metabolic engineering in Blastobotrys yeasts for their application in food, feed, and beyond, particularly for fatty acid-based fuels and oleochemicals. KEY POINTS: • The production of biolipids by heterotrophic yeasts is reviewed. • Summary of information concerning lipid metabolism regulation is highlighted. • Special focus on the importance of diacylglycerol acyltransferases encoding genes in improving lipid production is made.
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Affiliation(s)
- Daniel Ruben Akiola Sanya
- Université Paris-Saclay, Institut Micalis, Diversité génomique et fonctionnelle des levures, domaine de Vilvert, 78350, Jouy-en-Josas, France.
| | - Djamila Onésime
- Université Paris-Saclay, Institut Micalis, Diversité génomique et fonctionnelle des levures, domaine de Vilvert, 78350, Jouy-en-Josas, France
| | - Volkmar Passoth
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, PO Box 7015, SE-750 07, Uppsala, Sweden
| | - Mrinal K Maiti
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - Atrayee Chattopadhyay
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - Mahesh B Khot
- Laboratorio de Recursos Renovables, Centro de Biotecnologia, Universidad de Concepcion, Barrio Universitario s/n, Concepcion, Chile
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Ethanol tolerance assessment in recombinant E. coli of ethanol responsive genes from Lactobacillus buchneri NRRL B-30929. World J Microbiol Biotechnol 2020; 36:179. [PMID: 33155123 DOI: 10.1007/s11274-020-02953-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 10/23/2020] [Indexed: 01/24/2023]
Abstract
We previously identified specific proteins associated with ethanol stress response in a Lactobacillus buchneri strain capable of growing in 10% ethanol. In the current study, the exceptional roles of ethanol responsive genes are examined to determine if they can increase ethanol tolerance in E. coli host cells. The recombinant strains carrying ethanol responsive genes were subjected to growth analyses in media with and without 4% ethanol. Among the expression of these genes and growth analyses of the recombinant strains in ethanol, six genes Lbuc_0522 (NADPH-dependent methylglyoxal reductase), Lbuc_0354 (succinate semialdehyde dehydrogenase), Lbuc_1211(threonyl_tRNA synthetase), Lbuc_2051 (nitroreductase), Lbuc_0707 (branched chain amino acid aminotransferase) and Lbuc_1852 (proline-specific peptidase) conferred host cells tolerance to 4% ethanol. Six genes Lbuc_1523 (phage major capsid protein, HK 97 family), Lbuc_1319 (phosphoglycerate kinase), Lbuc_0787 encoding fumarylacetoacetate hydrolase, Lbuc_1219 encoding UDP-N-acetylmuramate-L-alanine ligase, Lbuc_0466 encoding ornithine carbamoyltransferase and Lbuc_0858 encoding glycine hydroxymethyltransferase showed no impact on growth in media with 4% ethanol with IPTG induction when compared with E. coli carrying control pET28b plasmid. The expression of two genes Lbuc_1557 (S-layer glycoprotein) and Lbuc_2157 (6-phosphogluconate dehydrogenase) resulted ethanol sensitivity phenotype.
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8
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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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9
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Ibarra LN, Alves AEODA, Antonino JD, Prado GS, Pinto CEM, Soccol CR, Vasconcelos ÉARD, Grossi-de-Sa MF. Enzymatic activity of a recombinant β-1,4-endoglucanase from the Cotton Boll Weevil (Anthonomus grandis) aiming second generation ethanol production. Sci Rep 2019; 9:19580. [PMID: 31862955 PMCID: PMC6925290 DOI: 10.1038/s41598-019-56070-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 11/20/2019] [Indexed: 01/22/2023] Open
Abstract
In the last years, the production of ethanol fuel has started to change with the introduction of second-generation ethanol (2 G Ethanol) in the energy sector. However, in Brazil, the process of obtaining 2 G ethanol did not reach a basic standard to achieve relevant and economically viable results. Several studies have currently been addressed to solve these issues. A critical stage in the bioethanol production is the deployment of efficient and stable enzymes to catalyze the saccharification step into the process of biomass conversion. The present study comprises a screening for genes coding for plant biomass degradation enzymes, followed by cloning a selected gene, addressing its heterologous expression, and characterizing enzymatic activity towards cellulose derived substrates, with a view to second-generation ethanol production. A cDNA database of the Cotton Boll Weevil, Anthonomus grandis (Coleoptera: Curculionidae), an insect that feeds on cotton plant biomass, was used as a source of plant biomass degradation enzyme genes. A larva and adult midgut-specific β-1,4-Endoglucanase-coding gene (AgraGH45-1) was cloned and expressed in the yeast Pichia pastoris. Its amino acid sequence, including the two catalytic domains, shares high identity with other Coleoptera Glycosyl Hydrolases from family 45 (GH45). AgraGH45-1 activity was detected in a Carboxymethylcellulose (CMC) and Hydroxyethylcellulose (HEC) degradation assay and the optimal conditions for enzymatic activity was pH 5.0 at 50 °C. When compared to commercial cellulase from Aspergillus niger, Agra GH45-1 was 1.3-fold more efficient to degrade HEC substrate. Together, these results show that AgraGH45-1 is a valid candidate to be engineered and be tested for 2 G ethanol production.
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Affiliation(s)
- Liz Nathalia Ibarra
- Universidade Federal do Paraná - UFPR, Curitiba, PR, 81530-980, Brazil.,Embrapa Recursos Genéticos e Biotecnologia, Brasília, DF, 70770-917, Brazil
| | - Ana Elizabeth Oliveira de Araújo Alves
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, DF, 70770-917, Brazil.,Universidade de Brasília - UnB, Biology Institute, Brasília, DF, 70910-900, Brazil
| | - José Dijair Antonino
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, DF, 70770-917, Brazil.,Universidade Federal Rural de Pernambuco - UFRPE, Recife-PE, 52171-900, Brazil
| | - Guilherme Souza Prado
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, DF, 70770-917, Brazil.,Universidade Católica de Brasília - UCB, Brasília, DF, 70790-160, Brazil
| | - Clidia Eduarda Moreira Pinto
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, DF, 70770-917, Brazil.,Universidade de Brasília - UnB, Biology Institute, Brasília, DF, 70910-900, Brazil
| | | | | | - Maria Fátima Grossi-de-Sa
- Embrapa Recursos Genéticos e Biotecnologia, Brasília, DF, 70770-917, Brazil.,Universidade Católica de Brasília - UCB, Brasília, DF, 70790-160, Brazil
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