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Sornlek W, Sonthirod C, Tangphatsornruang S, Ingsriswang S, Runguphan W, Eurwilaichtr L, Champreda V, Tanapongpipat S, Schaap PJ, Martins Dos Santos VAP. Genes controlling hydrolysate toxin tolerance identified by QTL analysis of the natural Saccharomyces cerevisiae BCC39850. Appl Microbiol Biotechnol 2024; 108:21. [PMID: 38159116 DOI: 10.1007/s00253-023-12843-3] [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: 04/17/2023] [Revised: 09/21/2023] [Accepted: 09/30/2023] [Indexed: 01/03/2024]
Abstract
Lignocellulosic material can be converted to valorized products such as fuels. Pretreatment is an essential step in conversion, which is needed to increase the digestibility of the raw material for microbial fermentation. However, pretreatment generates by-products (hydrolysate toxins) that are detrimental to microbial growth. In this study, natural Saccharomyces strains isolated from habitats in Thailand were screened for their tolerance to synthetic hydrolysate toxins (synHTs). The Saccharomyces cerevisiae natural strain BCC39850 (toxin-tolerant) was crossed with the laboratory strain CEN.PK2-1C (toxin-sensitive), and quantitative trait locus (QTL) analysis was performed on the segregants using phenotypic scores of growth (OD600) and glucose consumption. VMS1, DET1, KCS1, MRH1, YOS9, SYO1, and YDR042C were identified from QTLs as candidate genes associated with the tolerance trait. CEN.PK2-1C knockouts of the VMS1, YOS9, KCS1, and MRH1 genes exhibited significantly greater hydrolysate toxin sensitivity to growth, whereas CEN.PK2-1C knock-ins with replacement of VMS1 and MRH1 genes from the BCC39850 alleles showed significant increased ethanol production titers compared with the CEN.PK2-1C parental strain in the presence of synHTs. The discovery of VMS1, YOS9, MRH1, and KCS1 genes associated with hydrolysate toxin tolerance in S. cerevisiae indicates the roles of the endoplasmic-reticulum-associated protein degradation pathway, plasma membrane protein association, and the phosphatidylinositol signaling system in this trait. KEY POINTS: • QTL analysis was conducted using a hydrolysate toxin-tolerant S. cerevisiae natural strain • Deletion of VMS1, YOS9, MRH1, and KCS1 genes associated with hydrolysate toxin-sensitivity • Replacement of VMS1 and MRH1 with natural strain alleles increased ethanol production titers in the presence of hydrolysate toxins.
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Affiliation(s)
- Warasirin Sornlek
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, 12120, Pathum Thani, Thailand
- The Laboratory of Systems and Synthetic Biology, Wageningen University and Research, Stippeneng 4, 6708 WE, Wageningen, The Netherlands
| | - Chutima Sonthirod
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, 12120, Pathum Thani, Thailand
| | - Sithichoke Tangphatsornruang
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, 12120, Pathum Thani, Thailand
| | - Supawadee Ingsriswang
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, 12120, Pathum Thani, Thailand
| | - Weerawat Runguphan
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, 12120, Pathum Thani, Thailand
| | - Lily Eurwilaichtr
- National Energy Technology Center, 114 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, 12120, Pathum Thani, Thailand
| | - Verawat Champreda
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, 12120, Pathum Thani, Thailand
| | - Sutipa Tanapongpipat
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Phahonyothin Road, Khlong Nueng, Khlong Luang, 12120, Pathum Thani, Thailand.
| | - Peter J Schaap
- The Laboratory of Systems and Synthetic Biology, Wageningen University and Research, Stippeneng 4, 6708 WE, Wageningen, The Netherlands
| | - Vitor A P Martins Dos Santos
- The Laboratory of Systems and Synthetic Biology, Wageningen University and Research, Stippeneng 4, 6708 WE, Wageningen, The Netherlands.
- Bioprocess Engineering Group, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands.
- LifeGlimmer GmbH, Markelstrasse 38, 12163, Berlin, Germany.
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Sha Y, Zhou L, Wang Z, Ding Y, Lu M, Xu Z, Zhai R, Jin M. Adaptive laboratory evolution boost Yarrowia lipolytica tolerance to vanillic acid. J Biotechnol 2023; 367:42-52. [PMID: 36965629 DOI: 10.1016/j.jbiotec.2023.03.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 02/18/2023] [Accepted: 03/17/2023] [Indexed: 03/27/2023]
Abstract
Microbial tolerance to lignocellulose-derived inhibitors, such as aromatic acids, is critical for the economical production of biofuels and biochemicals. Here, adaptive laboratory evolution was applied to improve the tolerance of Yarrowia lipolytica to a representative aromatic acid inhibitor vanillic acid. The transcriptome profiling of evolved strain suggested that the tolerance could be related to the up-regulation of RNA processing and multidrug transporting pathways. Further analysis by reverse engineering confirmed that the amplification of YALI0_F13475g coding for transcriptional coactivator and YALI0_E25201g coding for multidrug transporter conferred tolerance not only to vanillic acid but also towards ferulic acid, p-coumaric acid, p-hydroxybenzoic acid and syringic acid. These findings suggested that regulation of RNA processing and multidrug transporting pathways may be important for enhanced aromatic acid tolerance in Y. lipolytica. This study provides valuable genetic information for robust strain construction for lignocellulosic biorefinery.
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Affiliation(s)
- Yuanyuan Sha
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Linlin Zhou
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Zedi Wang
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Ying Ding
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Minrui Lu
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Zhaoxian Xu
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Rui Zhai
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Mingjie Jin
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; Biorefinery Research Institution, Nanjing University of Science and Technology, Nanjing 210094, China.
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3
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Ciamponi FE, Procópio DP, Murad NF, Franco TT, Basso TO, Brandão MM. Multi-omics network model reveals key genes associated with p-coumaric acid stress response in an industrial yeast strain. Sci Rep 2022; 12:22466. [PMID: 36577778 PMCID: PMC9797568 DOI: 10.1038/s41598-022-26843-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 12/21/2022] [Indexed: 12/30/2022] Open
Abstract
The production of ethanol from lignocellulosic sources presents increasingly difficult issues for the global biofuel scenario, leading to increased production costs of current second-generation (2G) ethanol when compared to first-generation (1G) plants. Among the setbacks encountered in industrial processes, the presence of chemical inhibitors from pre-treatment processes severely hinders the potential of yeasts in producing ethanol at peak efficiency. However, some industrial yeast strains have, either naturally or artificially, higher tolerance levels to these compounds. Such is the case of S. cerevisiae SA-1, a Brazilian fuel ethanol industrial strain that has shown high resistance to inhibitors produced by the pre-treatment of cellulosic complexes. Our study focuses on the characterization of the transcriptomic and physiological impact of an inhibitor of this type, p-coumaric acid (pCA), on this strain under chemostat cultivation via RNAseq and quantitative physiological data. It was found that strain SA-1 tend to increase ethanol yield and production rate while decreasing biomass yield when exposed to pCA, in contrast to pCA-susceptible strains, which tend to decrease their ethanol yield and fermentation efficiency when exposed to this substance. This suggests increased metabolic activity linked to mitochondrial and peroxisomal processes. The transcriptomic analysis also revealed a plethora of differentially expressed genes located in co-expressed clusters that are associated with changes in biological pathways linked to biosynthetic and energetical processes. Furthermore, it was also identified 20 genes that act as interaction hubs for these clusters, while also having association with altered pathways and changes in metabolic outputs, potentially leading to the discovery of novel targets for metabolic engineering toward a more robust industrial yeast strain.
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Affiliation(s)
- F. E. Ciamponi
- grid.411087.b0000 0001 0723 2494Center for Molecular Biology and Genetic Engineering (CBMEG), State University of Campinas (Unicamp), Av. Cândido Rondon, 400, Campinas, SP 13083-875 Brazil
| | - D. P. Procópio
- grid.11899.380000 0004 1937 0722Department of Chemical Engineering, University of São Paulo (USP), Av. Prof. Luciano Gualberto, 380, São Paulo, SP 05508-010 Brazil
| | - N. F. Murad
- grid.411087.b0000 0001 0723 2494Center for Molecular Biology and Genetic Engineering (CBMEG), State University of Campinas (Unicamp), Av. Cândido Rondon, 400, Campinas, SP 13083-875 Brazil
| | - T. T. Franco
- grid.411087.b0000 0001 0723 2494School of Chemical Engineering (FEQ), State University of Campinas (Unicamp), Av. Albert Einstein, 500, Campinas, SP 13083-852 Brazil
| | - T. O. Basso
- grid.11899.380000 0004 1937 0722Department of Chemical Engineering, University of São Paulo (USP), Av. Prof. Luciano Gualberto, 380, São Paulo, SP 05508-010 Brazil
| | - M. M. Brandão
- grid.411087.b0000 0001 0723 2494Center for Molecular Biology and Genetic Engineering (CBMEG), State University of Campinas (Unicamp), Av. Cândido Rondon, 400, Campinas, SP 13083-875 Brazil
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Jung R, Karabín M, Jelínek L, Dostálek P. Balance of volatile phenols originating from wood- and peat-smoked malt during the brewing process. Eur Food Res Technol 2022. [DOI: 10.1007/s00217-022-04130-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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5
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Yi X, Wu J, Jiang H, Zhao Y, Mei J. Kinase expression enhances phenolic aldehydes conversion and ethanol fermentability of Zymomonas mobilis. Bioprocess Biosyst Eng 2022; 45:1319-1329. [PMID: 35786774 DOI: 10.1007/s00449-022-02747-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 06/11/2022] [Indexed: 11/26/2022]
Abstract
Kinases modulate the various physiological activities of microbial fermenting strains including the conversion of lignocellulose-derived phenolic aldehydes (4-hydroxyaldehyde, vanillin, and syringaldehyde). Here, we comprehensively investigated the gene transcriptional profiling of the kinases under the stress of phenolic aldehydes for ethanologenic Zymomonas mobilis using DNA microarray. Among 47 kinase genes, three genes of ZMO0003 (adenylylsulfate kinase), ZMO1162 (histidine kinase), and ZMO1391 (diacylglycerol kinase), were differentially expressed against 4-hydroxybenzaldehyde and vanillin, in which the overexpression of ZMO1162 promoted the phenolic aldehydes conversion and ethanol fermentability. The perturbance originated from plasmid-based expression of ZMO1162 gene contributed to a unique expression profiling of genome-encoding genes under all three phenolic aldehydes stress. Differentially expressed ribosome genes were predicted as one of the main contributors to phenolic aldehydes conversion and thus finally enhanced ethanol fermentability for Z. mobilis ZM4. The results provided an insight into the kinases on regulation of phenolic aldehydes conversion and ethanol fermentability for Z. mobilis ZM4, as well as the target object for rational design of robust biorefinery strains.
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Affiliation(s)
- Xia Yi
- Jiangxi Provincial Key Laboratory of Systems Biomedicine, Jiujiang University, 17 Lufeng Road, Jiujiang, 332000, China.
- National-Local Joint Engineering Research Center for Biomass Refining and High-Quality Utilization, Changzhou University, Changzhou, 213164, China.
| | - Jianfang Wu
- Jiangxi Provincial Key Laboratory of Systems Biomedicine, Jiujiang University, 17 Lufeng Road, Jiujiang, 332000, China
| | - He Jiang
- Jiangxi Provincial Key Laboratory of Systems Biomedicine, Jiujiang University, 17 Lufeng Road, Jiujiang, 332000, China
| | - Yan Zhao
- Jiangxi Provincial Key Laboratory of Systems Biomedicine, Jiujiang University, 17 Lufeng Road, Jiujiang, 332000, China
| | - Jun Mei
- Jiangxi Provincial Key Laboratory of Systems Biomedicine, Jiujiang University, 17 Lufeng Road, Jiujiang, 332000, China
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6
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Chanda K, Mozumder AB, Chorei R, Gogoi RK, Prasad HK. A Lignocellulolytic Colletotrichum sp. OH with Broad-Spectrum Tolerance to Lignocellulosic Pretreatment Compounds and Derivatives and the Efficiency to Produce Hydrogen Peroxide and 5-Hydroxymethylfurfural Tolerant Cellulases. J Fungi (Basel) 2021; 7:785. [PMID: 34682207 PMCID: PMC8540663 DOI: 10.3390/jof7100785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/04/2021] [Accepted: 09/07/2021] [Indexed: 10/25/2022] Open
Abstract
Fungal endophytes are an emerging source of novel traits and biomolecules suitable for lignocellulosic biomass treatment. This work documents the toxicity tolerance of Colletotrichum sp. OH toward various lignocellulosic pretreatment-derived inhibitors. The effects of aldehydes (vanillin, p-hydroxybenzaldehyde, furfural, 5-hydroxymethylfurfural; HMF), acids (gallic, formic, levulinic, and p-hydroxybenzoic acid), phenolics (hydroquinone, p-coumaric acid), and two pretreatment chemicals (hydrogen peroxide and ionic liquid), on the mycelium growth, biomass accumulation, and lignocellulolytic enzyme activities, were tested. The reported Colletotrichum sp. OH was naturally tolerant to high concentrations of single inhibitors like HMF (IC50; 17.5 mM), levulinic acid (IC50; 29.7 mM), hydroquinone (IC50; 10.76 mM), and H2O2 (IC50; 50 mM). The lignocellulolytic enzymes displayed a wide range of single and mixed inhibitor tolerance profiles. The enzymes β-glucosidase and endoglucanase showed H2O2- and HMF-dependent activity enhancements. The enzyme β-glucosidase activity was 34% higher in 75 mM and retained 20% activity in 125 mM H2O2. Further, β-glucosidase activity increased to 24 and 32% in the presence of 17.76 and 8.8 mM HMF. This research suggests that the Colletotrichum sp. OH, or its enzymes, can be used to pretreat plant biomass, hydrolyze it, and remove inhibitory by-products.
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Affiliation(s)
| | | | | | | | - Himanshu Kishore Prasad
- Department of Life Science and Bioinformatics, Assam University, Silchar 788011, India; (K.C.); (A.B.M.); (R.C.); (R.K.G.)
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7
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Yi X, Mei J, Lin L, Wang W. Overexpression of Dioxygenase Encoding Gene Accelerates the Phenolic Aldehyde Conversion and Ethanol Fermentability of Zymomonas mobilis. Appl Biochem Biotechnol 2021; 193:3017-3027. [PMID: 33826067 DOI: 10.1007/s12010-021-03551-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 03/22/2021] [Indexed: 11/27/2022]
Abstract
NADH-dependent reductase enzyme catalyzes the phenolic aldehyde conversion and correspondingly improves the ethanol fermentability of the ethanologenic Zymomonas mobilis. This study constructed the transcriptional landscape of mono/dioxygenase genes in Z. mobilis ZM4 under the stress of the toxic phenolic aldehyde inhibitors of 4-hydroxybenzaldehyde, syringaldehyde, and vanillin. One specific dioxygenase encoding gene ZMO1721 was differentially expressed by 3.07-folds under the stress of 4-hydroxybenzaldehyde among the eleven mono/dioxygenase genes. The purified ZMO1721 shared 99.9% confidence and 48.0% identity with the oxidoreductase in Rhodoferax ferrireducens T118 was assayed and the NADH-dependent reduction activity was confirmed for phenolic aldehyde vanillin conversion. The ZMO1721 gene was then overexpressed in Z. mobilis ZM4 and the 4-hydroxybenzaldehyde conversion rate was accelerated. The cell growth, glucose consumption, and ethanol productivity of Z. mobilis ZM4 were also improved by ZMO1721 overexpression. The genes identified on improving phenolic aldehyde tolerance and ethanol fermentability in this study could be used as the synthetic biology tools for modification of ethanologenic strains.
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Affiliation(s)
- Xia Yi
- Jiangxi Provincial Key Laboratory of Systems Biomedicine, Jiujiang University, 17 Lufeng Road, Jiujiang, 332000, China.
| | - Jun Mei
- Jiangxi Provincial Key Laboratory of Systems Biomedicine, Jiujiang University, 17 Lufeng Road, Jiujiang, 332000, China
| | - Ling Lin
- Jiangxi Provincial Key Laboratory of Systems Biomedicine, Jiujiang University, 17 Lufeng Road, Jiujiang, 332000, China
| | - Wei Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
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Wang Z, Zhou L, Lu M, Zhang Y, Perveen S, Zhou H, Wen Z, Xu Z, Jin M. Adaptive laboratory evolution of Yarrowia lipolytica improves ferulic acid tolerance. Appl Microbiol Biotechnol 2021; 105:1745-1758. [PMID: 33523248 DOI: 10.1007/s00253-021-11130-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/26/2020] [Accepted: 01/19/2021] [Indexed: 12/17/2022]
Abstract
Yarrowia lipolytica strain is a promising cell factory for the conversion of lignocellulose to biofuels and bioproducts. Despite the inherent robustness of this strain, further improvements to lignocellulose-derived inhibitors toxicity tolerance of Y. lipolytica are also required to achieve industrial application. Here, adaptive laboratory evolution was employed with increasing concentrations of ferulic acid. The adaptive laboratory evolution experiments led to evolve Y. lipolytica strain yl-XYL + *FA*4 with increased tolerance to ferulic acid as compared to the parental strain. Specifically, the evolved strain could tolerate 1.5 g/L ferulic acid, whereas 0.5 g/L ferulic acid could cause about 90% lethality of the parental strain. Transcriptome analysis of the evolved strain revealed several targets underlying toxicity tolerance enhancements. YALI0_E25201g, YALI0_F05984g, YALI0_B18854g, and YALI0_F16731g were among the highest upregulated genes, and the beneficial contributions of these genes were verified via reverse engineering. Recombinant strains with overexpressing each of these four genes obtained enhanced tolerance to ferulic acid as compared to the control strain. Fortunately, recombinant strains with overexpression of YALI0_E25201g, YALI0_B18854g, and YALI0_F16731g individually also obtained enhanced tolerance to vanillic acid. Overall, this work demonstrated a whole strain improvement cycle by "non-rational" metabolic engineering and presented new targets to modify Y. lipolytica for microbial lignocellulose valorization. KEY POINTS: • Adaptive evolution improved the ferulic acid tolerance of Yarrowia lipolytica • Transcriptome sequence was applied to analyze the ferulic acid tolerate strain • Three genes were demonstrated for both ferulic acid and vanillic acid tolerance.
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Affiliation(s)
- Zedi Wang
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China
| | - Linlin Zhou
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China
| | - Minrui Lu
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China
| | - Yuwei Zhang
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China
| | - Samina Perveen
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China
| | - Huarong Zhou
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China
| | - Zhiqiang Wen
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
| | - Zhaoxian Xu
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
| | - Mingjie Jin
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
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Evaluating the Effect of Lignocellulose-Derived Microbial Inhibitors on the Growth and Lactic Acid Production by Bacillus coagulans Azu-10. FERMENTATION-BASEL 2021. [DOI: 10.3390/fermentation7010017] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Effective lactic acid (LA) production from lignocellulosic biomass materials is challenged by several limitations related to pentose sugar utilization, inhibitory compounds, and/or fermentation conditions. In this study, a newly isolated Bacillus coagulans strain Azu-10 was obtained and showed homofermentative LA production from xylose with optimal fermentation conditions at 50 °C and pH 7.0. Growth of strain Azu-10 and LA-fermentation efficiency were evaluated in the presence of various lignocellulose-derived inhibitors (furans, carboxylic acids, and phenols) at different concentrations. Furanic lignocellulosic-derived inhibitors were completely detoxified. The strain has exhibited high biomass, complete xylose consumption, and high LA production in the presence of 1.0–4.0 g/L furfural and 1.0–5.0 g/L of hydroxymethyl furfural, separately. Moreover, strain Azu-10 exhibited high LA production in the presence of 5.0–15.0 g/L acetic acid, 5.0 g/L of formic acid, and up to 7.0 g/L of levulinic acid, separately. Besides, for phenolic compounds, p-coumaric acid was most toxic at 1.0 g/L, while syringaldehyde or p-hydroxybenzaldehyde, and vanillin at 1.0 g/L did not inhibit LA fermentation. The present study provides an interesting potential candidate for the thermophilic LA fermentation from lignocellulose-derived substrates at the industrial biorefinery level.
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Ilanidis D, Wu G, Stagge S, Martín C, Jönsson LJ. Effects of redox environment on hydrothermal pretreatment of lignocellulosic biomass under acidic conditions. BIORESOURCE TECHNOLOGY 2021; 319:124211. [PMID: 33045548 DOI: 10.1016/j.biortech.2020.124211] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/28/2020] [Accepted: 09/29/2020] [Indexed: 05/23/2023]
Abstract
The effects of the redox environment on acidic hydrothermal pretreatment were investigated in experiments with sugarcane bagasse (190 °C, 14 min) and Norway spruce (205 °C, 5 min). To modulate the redox environment, pretreatment was performed without gas addition, with N2, or with O2. Analyses covered pretreated solids, pretreatment liquids, condensates, enzymatic digestibility, and inhibitory effects of pretreatment liquids on yeast. Addition of gas, especially O2, resulted in increased severity, as reflected by up to 18 percent units lower recoveries of pretreated solids, up to 31 percent units lower glucan recoveries, improved hemicellulose removal, formation of pseudo-lignin, improved overall glucan conversion, and increased concentrations of several microbial inhibitors. Some inhibitors, such as formaldehyde and coniferyl aldehyde, did not, however, follow that pattern. TAC (Total Aromatic Content) values reflected inhibitory effects of pretreatment liquids. This study demonstrates how gas addition can be used to modulate the severity of acidic hydrothermal pretreatment.
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Affiliation(s)
| | - Guochao Wu
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
| | - Stefan Stagge
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
| | - Carlos Martín
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
| | - Leif J Jönsson
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden.
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11
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Teymennet-Ramírez KV, Martínez-Morales F, Muñoz-Garay C, Bertrand B, Morales-Guzmán D, Trejo-Hernández MR. Laccase treatment of phenolic compounds for bioethanol production and the impact of these compounds on yeast physiology. BIOCATAL BIOTRANSFOR 2020. [DOI: 10.1080/10242422.2020.1856820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Karla V. Teymennet-Ramírez
- Centro de Investigación en Biotecnología, Universidad Autónoma del Estado de Morelos, Cuernavaca, México
| | - Fernando Martínez-Morales
- Centro de Investigación en Biotecnología, Universidad Autónoma del Estado de Morelos, Cuernavaca, México
| | - Carlos Muñoz-Garay
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México (ICF-UNAM), Cuernavaca, México
| | - Brandt Bertrand
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México (ICF-UNAM), Cuernavaca, México
| | - Daniel Morales-Guzmán
- Centro de Investigación en Biotecnología, Universidad Autónoma del Estado de Morelos, Cuernavaca, México
| | - María R. Trejo-Hernández
- Centro de Investigación en Biotecnología, Universidad Autónoma del Estado de Morelos, Cuernavaca, México
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12
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Walls LE, Rios-Solis L. Sustainable Production of Microbial Isoprenoid Derived Advanced Biojet Fuels Using Different Generation Feedstocks: A Review. Front Bioeng Biotechnol 2020; 8:599560. [PMID: 33195174 PMCID: PMC7661957 DOI: 10.3389/fbioe.2020.599560] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 10/09/2020] [Indexed: 01/17/2023] Open
Abstract
As the fastest mode of transport, the aircraft is a major driver for globalization and economic growth. The development of alternative advanced liquid fuels is critical to sustainable development within the sector. Such fuels should be compatible with existing infrastructure and derived from second generation feedstocks to avoid competition with food markets. With properties similar to petroleum based fuels, isoprenoid derived compounds such as limonene, bisabolane, farnesane, and pinene dimers are of increasing interest as "drop-in" replacement jet fuels. In this review potential isoprenoid derived jet fuels and progress toward their microbial production was discussed in detail. Although substantial advancements have been achieved, the use of first generation feedstocks remains ubiquitous. Lignocellulosic biomass is the most abundant raw material available for biofuel production, however, technological constraints associated with its pretreatment and saccharification hinder its economic feasibility for low-value commodity production. Non-conventional microbes with novel characteristics including cellulolytic bacteria and fungi capable of highly efficient lignocellulose degradation and xylose fermenting oleaginous yeast with enhanced lignin-associated inhibitor tolerance were investigated as alternatives to traditional model hosts. Finally, innovative bioprocessing methods including consolidated bioprocessing and sequential bioreactor approaches, with potential to capitalize on such unique natural capabilities were considered.
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Affiliation(s)
- Laura Ellen Walls
- Institute for Bioengineering, School of Engineering, The University of Edinburgh, Edinburgh, United Kingdom
- Centre for Synthetic and Systems Biology (SynthSys), The University of Edinburgh, Edinburgh, United Kingdom
| | - Leonardo Rios-Solis
- Institute for Bioengineering, School of Engineering, The University of Edinburgh, Edinburgh, United Kingdom
- Centre for Synthetic and Systems Biology (SynthSys), The University of Edinburgh, Edinburgh, United Kingdom
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Gares M, Hiligsmann S, Kacem Chaouche N. Lignocellulosic biomass and industrial bioprocesses for the production of second generation bio-ethanol, does it have a future in Algeria? SN APPLIED SCIENCES 2020. [DOI: 10.1007/s42452-020-03442-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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14
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Liu H, Zhang J, Yuan J, Jiang X, Jiang L, Li Z, Yin Z, Du Y, Zhao G, Liu B, Huang D. Gene coexpression network analysis reveals a novel metabolic mechanism of Clostridium acetobutylicum responding to phenolic inhibitors from lignocellulosic hydrolysates. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:163. [PMID: 32999686 PMCID: PMC7520030 DOI: 10.1186/s13068-020-01802-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 09/12/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Lignocellulosic biomass is a promising resource of renewable biochemicals and biofuels. However, the presence of inhibitors existing in lignocellulosic hydrolysates (LCH) is a great challenge to acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum. In particular, phenolic compounds (PCs) from LCH severely block ABE production even at low concentrations. Thus, it is urgent to gain insight into the intracellular metabolic disturbances caused by phenolic inhibitors and elucidate the underlying mechanisms to identify key industrial bottlenecks that undermine efficient ABE production. RESULTS In this study, a time-course of ABE fermentation by C. acetobutylicum in the presence of four typical PCs (syringaldehyde, vanillin, ferulic acid, and p-coumaric acid) was characterized, respectively. Addition of PCs caused different irreversible effects on ABE production. Specifically, syringaldehyde showed the greatest inhibition to butanol production, followed by vanillin, ferulic acid, and p-coumaric acid. Subsequently, a weighted gene co-expression network analysis (WGCNA) based on RNA-sequencing data was applied to identify metabolic perturbations caused by four LCH-derived PCs, and extract the gene modules associated with extracellular fermentation traits. The hub genes in each module were subjected to protein-protein interaction analysis and enrichment analysis. The results showed that functional modules were PC-dependent and shared some unique features. Specifically, p-coumaric acid caused the most extensive transcriptomic disturbances, particularly affecting the gene expressions of ribosome proteins and the assembly of flagella, DNA replication, repair, and recombination; the addition of syringaldehyde caused significant metabolic disturbances on the gene expressions of ribosome proteins, starch and sucrose metabolism; vanillin mainly disturbed purine metabolism, sporulation and signal transduction; and ferulic acid caused a metabolic disturbance on glycosyl transferase-related gene expressions. CONCLUSION This study uncovers novel insights into the inhibitory mechanisms of PCs for the first time and provides guidance for future metabolic engineering efforts, which establishes a powerful foundation for the development of phenol-tolerant strains of C. acetobutylicum for economically sustainable ABE production with high productivity from lignocellulosic biomass.
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Affiliation(s)
- Huanhuan Liu
- State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Tianjin, 300457 China
- Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Ministry of Education, Tianjin, 300457 China
| | - Jing Zhang
- State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Tianjin, 300457 China
- Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Ministry of Education, Tianjin, 300457 China
| | - Jian Yuan
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, 300457 China
| | - Xiaolong Jiang
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, 300457 China
| | - Lingyan Jiang
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, 300457 China
| | - Zhenjing Li
- State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Tianjin, 300457 China
- Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Ministry of Education, Tianjin, 300457 China
| | - Zhiqiu Yin
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, 300457 China
| | - Yuhui Du
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, 300457 China
| | - Guang Zhao
- Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Qingdao, 266101 China
| | - Bin Liu
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, 300457 China
| | - Di Huang
- TEDA Institute of Biological Sciences and Biotechnology, Tianjin Key Laboratory of Microbial Functional Genomics, Nankai University, Tianjin, 300457 China
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Qiu Z, Fang C, He N, Bao J. An oxidoreductase gene ZMO1116 enhances the p-benzoquinone biodegradation and chiral lactic acid fermentability of Pediococcus acidilactici. J Biotechnol 2020; 323:231-237. [PMID: 32866539 DOI: 10.1016/j.jbiotec.2020.08.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 08/19/2020] [Accepted: 08/26/2020] [Indexed: 10/23/2022]
Abstract
p-Benzoquinone (BQ) is a lignin-derived inhibitor to microbial strains. Unlike the furan inhibitors, p-benzoquinone is recalcitrant to traditional detoxification methods. This study shows a biological degradation of p-benzoquinone and a simultaneous D-lactic acid fermentation by an engineered Pediococcus acidilactici strain. The overexpression of an oxidoreductase gene ZMO1116 from Zymomonas mobilis encoding oxidoreductase was identified to improve the D-lactic acid fermentability of P. acidilactici against p-benzoquinone. The gene ZMO1116 was integrated into the genome of P. acidilactici and enabled the engineered P. acidilactici to convert p-benzoquinone into less toxic hydroquinone (HQ), resulting in the improved p-benzoquinone tolerance. Simultaneous saccharification and co-fermentation (SSCF) was conducted using the pretreated and biodetoxified corn stover containing p-benzoquinone, the D-lactic acid production of the engineered strain (123.8 g/L) was 21.4 % higher than the parental strain (102.0 g/L). This study provides a practical method on robust p-benzoquinone tolerance and efficient cellulosic chiral lactic acid fermentation from lignocellulose feedstock.
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Affiliation(s)
- Zhongyang Qiu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China; Jiangsu Key Laboratory for Biomass-based Energy and Enzyme Technology, Huaiyin Normal University, 111 West Changjiang Road, Huaian, Jiangsu 223300, China
| | - Chun Fang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Niling He
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Jie Bao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
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Chiavarino B, Dopfer O, Crestoni ME, Corinti D, Maître P, Fornarini S. IRMPD Spectra of Protonated Hydroxybenzaldehydes: Evidence of Torsional Barriers in Carboxonium Ions. Chemphyschem 2020; 21:749-761. [PMID: 31951044 DOI: 10.1002/cphc.202000041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Indexed: 11/09/2022]
Abstract
Protonation at the formyl oxygen atom of benzaldehydes leading to the formation of carboxonium ions yields two distinct isomers, depending on the relative orientation of the proton either cis or trans with respect to the hydrogen atom on the adjacent carbon. In this context, the IR multiple photon dissociation (IRMPD) spectra of protonated ortho, meta, and para-hydroxybenzaldehydes (OH-BZH+ ), delivered into the gas phase by electrospray ionization of hydro-alcoholic solutions, are reported in the 3200-3700 cm-1 spectral range. This range is characteristic of O-H stretching modes and thus able to differentiate cis and trans carboxonium isomers. Comparison between IRMPD spectra and DFT calculations at the B3LYP/6-311++G(2df2p) level suggests that for both p-OH-BZH+ and m-OH-BZH+ only cis conformers are present in the ion population analyzed. For o-OH-BZH+ , IRMPD spectroscopy points to a mixture comprising one trans and more than one cis conformers. The energy barrier for cis-trans isomerization calculated for each OH-BZH+ isomer is a measure of the degree of π-electron delocalization. Furthermore, IRMPD spectra of p-OH-BZH+ , m-OH-BZH+ and protonated phenol (this last used as reference) were recorded also in the fingerprint range. Both the observed C-O and O-H stretching vibrations appear to be a measure of π-electron delocalization in the ions.
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Affiliation(s)
- Barbara Chiavarino
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", P.le A. Moro 5, 00185, Roma, Italy
| | - Otto Dopfer
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstrasse 36, 10623, Berlin, Germany
| | - Maria Elisa Crestoni
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", P.le A. Moro 5, 00185, Roma, Italy
| | - Davide Corinti
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", P.le A. Moro 5, 00185, Roma, Italy
| | - Philippe Maître
- Institut de Chimie Physique, UMR8000, CNRS, Université Paris-Saclay, 91405, Orsay, France
| | - Simonetta Fornarini
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", P.le A. Moro 5, 00185, Roma, Italy
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17
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Castaño-Cerezo S, Fournié M, Urban P, Faulon JL, Truan G. Development of a Biosensor for Detection of Benzoic Acid Derivatives in Saccharomyces cerevisiae. Front Bioeng Biotechnol 2020; 7:372. [PMID: 31970152 PMCID: PMC6959289 DOI: 10.3389/fbioe.2019.00372] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 11/13/2019] [Indexed: 01/14/2023] Open
Abstract
4-hydroxybenzoic acid (pHBA) is an important industrial precursor of muconic acid and liquid crystal polymers whose production is based on the petrochemical industry. In order to decrease our dependency on fossil fuels and improve sustainability, microbial engineering is a particularly appealing approach for replacing traditional chemical techniques. The optimization of microbial strains, however, is still highly constrained by the screening stage. Biosensors have helped to alleviate this problem by decreasing the screening time as well as enabling higher throughput. In this paper, we constructed a synthetic biosensor, named sBAD, consisting of a fusion of the pHBA-binding domain of HbaR from R. palustris, the LexA DNA binding domain at the N-terminus and the transactivation domain B112 at the C-terminus. The response of sBAD was tested in the presence of different benzoic acid derivatives, with cell fluorescence output measured by flow cytometry. The biosensor was found to be activated by the external addition of pHBA in the culture medium, in addition to other carboxylic acids including p-aminobenzoic acid (pABA), salicylic acid, anthranilic acid, aspirin, and benzoic acid. Furthermore, we were able to show that this biosensor could detect the in vivo production of pHBA in a genetically modified yeast strain. A good linearity was observed between the biosensor fluorescence and pHBA concentration. Thus, this biosensor would be well-suited as a high throughput screening tool to produce, via metabolic engineering, benzoic acid derivatives.
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Affiliation(s)
| | - Mathieu Fournié
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Philippe Urban
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Jean-Loup Faulon
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France.,Chemistry School, Manchester Institute of Biotechnology, The University of Manchester, Manchester, United Kingdom
| | - Gilles Truan
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
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Smekenov I, Bakhtambayeva M, Bissenbayev K, Saparbayev M, Taipakova S, Bissenbaev AK. Heterologous secretory expression of β-glucosidase from Thermoascus aurantiacus in industrial Saccharomyces cerevisiae strains. Braz J Microbiol 2019; 51:107-123. [PMID: 31776864 DOI: 10.1007/s42770-019-00192-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 11/14/2019] [Indexed: 10/25/2022] Open
Abstract
The use of plant biomass for biofuel production will require efficient utilization of the sugars in lignocellulose, primarily cellobiose, because it is the major soluble by-product of cellulose and acts as a strong inhibitor, especially for cellobiohydrolase, which plays a key role in cellulose hydrolysis. Commonly used ethanologenic yeast Saccharomyces cerevisiae is unable to utilize cellobiose; accordingly, genetic engineering efforts have been made to transfer β-glucosidase genes enabling cellobiose utilization. Nonetheless, laboratory yeast strains have been employed for most of this research, and such strains may be difficult to use in industrial processes because of their generally weaker resistance to stressors and worse fermenting abilities. The purpose of this study was to engineer industrial yeast strains to ferment cellobiose after stable integration of tabgl1 gene that encodes a β-glucosidase from Thermoascus aurantiacus (TaBgl1). The recombinant S. cerevisiae strains obtained in this study secrete TaBgl1, which can hydrolyze cellobiose and produce ethanol. This study clearly indicates that the extent of glycosylation of secreted TaBgl1 depends from the yeast strains used and is greatly influenced by carbon sources (cellobiose or glucose). The recombinant yeast strains showed high osmotolerance and resistance to various concentrations of ethanol and furfural and to high temperatures. Therefore, these yeast strains are suitable for ethanol production processes with saccharified lignocellulose.
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Affiliation(s)
- Izat Smekenov
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040.,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040
| | - Marzhan Bakhtambayeva
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040.,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040
| | - Kudaybergen Bissenbayev
- Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040.,Nazarbayev Intellectual School, Almaty, Kazakhstan, 050044
| | - Murat Saparbayev
- Gustave Roussy Cancer Campus, CNRS UMR8200, Université Paris-Sud, F-94805, Villejuif Cedex, France
| | - Sabira Taipakova
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040.,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040
| | - Amangeldy K Bissenbaev
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040. .,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040.
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Mechanism of Tolerance to the Lignin-Derived Inhibitor p-Benzoquinone and Metabolic Modification of Biorefinery Fermentation Strains. Appl Environ Microbiol 2019; 85:AEM.01443-19. [PMID: 31492664 DOI: 10.1128/aem.01443-19] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 08/26/2019] [Indexed: 11/20/2022] Open
Abstract
p-Benzoquinone (BQ) is a lignin-derived inhibitor of biorefinery fermentation strains produced during pretreatment of lignocellulose. Unlike the well-studied inhibitors furan aldehydes, weak acids, and phenolics, the inhibitory properties of BQ, the microbial tolerance mechanism, and the detoxification strategy for this inhibitor have not been clearly elucidated. Here, BQ was identified as a by-product generated during acid pretreatment of various lignocellulose feedstocks, including corn stover, wheat straw, rice straw, tobacco stem, sunflower stem, and corncob residue. BQ at 20 to 200 mg/liter severely inhibited the cell growth and fermentability of various bacteria and yeast strains used in biorefinery fermentations. The BQ tolerance of the strains was found to be closely related to their capacity to convert BQ to nontoxic hydroquinone (HQ). To identify the key genes responsible for BQ tolerance, transcription levels of 20 genes potentially involved in the degradation of BQ in Zymomonas mobilis were investigated using real-time quantitative PCR in BQ-treated cells. One oxidoreductase gene, one hydroxylase gene, three reductase genes, and three dehydrogenase genes were found to be responsible for the conversion of BQ to HQ. Overexpression of the five key genes in Z. mobilis (ZMO1696, ZMO1949, ZMO1576, ZMO1984, and ZMO1399) accelerated its cell growth and cellulosic ethanol production in BQ-containing medium and lignocellulose hydrolysates.IMPORTANCE This study advances our understanding of BQ inhibition behavior and the mechanism of microbial tolerance to this inhibitor and identifies the key genes responsible for BQ detoxification. The insights here into BQ toxicity and tolerance provide the basis for future synthetic biology to engineer industrial fermentation strains with enhanced BQ tolerance.
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Favaro L, Jansen T, van Zyl WH. Exploring industrial and naturalSaccharomyces cerevisiaestrains for the bio-based economy from biomass: the case of bioethanol. Crit Rev Biotechnol 2019; 39:800-816. [DOI: 10.1080/07388551.2019.1619157] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Lorenzo Favaro
- Department of Agronomy Food Natural resources Animals and Environment (DAFNAE), University of Padova, Legnaro, Italy
| | - Trudy Jansen
- Department of Microbiology, Stellenbosch University, Stellenbosch, South Africa
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de Souza WR, Pacheco TF, Duarte KE, Sampaio BL, de Oliveira Molinari PA, Martins PK, Santiago TR, Formighieri EF, Vinecky F, Ribeiro AP, da Cunha BADB, Kobayashi AK, Mitchell RAC, de Sousa Rodrigues Gambetta D, Molinari HBC. Silencing of a BAHD acyltransferase in sugarcane increases biomass digestibility. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:111. [PMID: 31080518 PMCID: PMC6501328 DOI: 10.1186/s13068-019-1450-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 04/25/2019] [Indexed: 05/25/2023]
Abstract
BACKGROUND Sugarcane (Saccharum spp.) covers vast areas of land (around 25 million ha worldwide), and its processing is already linked into infrastructure for producing bioethanol in many countries. This makes it an ideal candidate for improving composition of its residues (mostly cell walls), making them more suitable for cellulosic ethanol production. In this paper, we report an approach to improving saccharification of sugarcane straw by RNAi silencing of the recently discovered BAHD01 gene responsible for feruloylation of grass cell walls. RESULTS We identified six BAHD genes in the sugarcane genome (SacBAHDs) and generated five lines with substantially decreased SacBAHD01 expression. To find optimal conditions for determining saccharification of sugarcane straw, we tried multiple combinations of solvent and temperature pretreatment conditions, devising a predictive model for finding their effects on glucose release. Under optimal conditions, demonstrated by Organosolv pretreatment using 30% ethanol for 240 min, transgenic lines showed increases in saccharification efficiency of up to 24%. The three lines with improved saccharification efficiency had lower cell-wall ferulate content but unchanged monosaccharide and lignin compositions. CONCLUSIONS The silencing of SacBAHD01 gene and subsequent decrease of cell-wall ferulate contents indicate a promising novel biotechnological approach for improving the suitability of sugarcane residues for cellulosic ethanol production. In addition, the Organosolv pretreatment of the genetically modified biomass and the optimal conditions for the enzymatic hydrolysis presented here might be incorporated in the sugarcane industry for bioethanol production.
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Affiliation(s)
- Wagner Rodrigo de Souza
- Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
- Centre of Natural Sciences and Humanities, Federal University of ABC, São Bernardo do Campo, SP 09606-045 Brazil
| | - Thályta Fraga Pacheco
- Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | - Karoline Estefani Duarte
- Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | - Bruno Leite Sampaio
- Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | | | - Polyana Kelly Martins
- Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | - Thaís Ribeiro Santiago
- Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | | | - Felipe Vinecky
- Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | - Ana Paula Ribeiro
- Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
| | | | - Adilson Kenji Kobayashi
- Genetics and Biotechnology Laboratory, Embrapa Agroenergy (CNPAE), Brasília, DF 70770-901 Brazil
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Hacısalihoğlu B, Holyavkin C, Topaloğlu A, Kısakesen Hİ, Çakar ZP. Genomic and transcriptomic analysis of a coniferyl aldehyde-resistant Saccharomyces cerevisiae strain obtained by evolutionary engineering. FEMS Yeast Res 2019; 19:5369625. [DOI: 10.1093/femsyr/foz021] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 03/03/2019] [Indexed: 12/19/2022] Open
Abstract
ABSTRACT
Phenolic inhibitors in lignocellulosic hydrolysates interfere with the performance of fermenting microorganisms. Among these, coniferyl aldehyde is one of the most toxic inhibitors. In this study, genetically stable Saccharomyces cerevisiae mutants with high coniferyl aldehyde resistance were successfully obtained for the first time by using an evolutionary engineering strategy, based on the systematic application of increasing coniferyl aldehyde stress in batch cultures. Among the selected coniferyl aldehyde-resistant mutants, the highly resistant strain called BH13 was also cross-resistant to other phenolic inhibitors, vanillin, ferulic acid and 4-hydroxybenzaldehyde. In the presence of 1.2 mM coniferyl aldehyde stress, BH13 had a significantly reduced lag phase, which was less than 3 h and only about 25% of that of the reference strain and converted coniferyl aldehyde faster. Additionally, there was no reduction in its growth rate, either. Comparative transcriptomic analysis of a highly coniferyl aldehyde-resistant mutant revealed upregulation of the genes involved in energy pathways, response to oxidative stress and oxidoreductase activity in the mutant strain BH13, already under non-stress conditions. Transcripts associated with pleiotropic drug resistance were also identified as upregulated. Genome re-sequencing data generally supported transcriptomic results and identified gene targets that may have a potential role in coniferyl aldehyde resistance.
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Affiliation(s)
- Burcu Hacısalihoğlu
- Department of Molecular Biology and Genetics, Faculty of Science & Letters, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
- Dr. Orhan Öcalgiray Molecular Biology, Biotechnology and Genetics Research Center (İTÜ-MOBGAM), Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
- Department of Molecular Biology and Genetics, Faculty of Science, Erzurum Technical University, Erzurum, 25050, Turkey
| | - Can Holyavkin
- Department of Molecular Biology and Genetics, Faculty of Science & Letters, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
- Dr. Orhan Öcalgiray Molecular Biology, Biotechnology and Genetics Research Center (İTÜ-MOBGAM), Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
| | - Alican Topaloğlu
- Department of Molecular Biology and Genetics, Faculty of Science & Letters, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
- Dr. Orhan Öcalgiray Molecular Biology, Biotechnology and Genetics Research Center (İTÜ-MOBGAM), Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
| | - Halil İbrahim Kısakesen
- Department of Molecular Biology and Genetics, Faculty of Science & Letters, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
- Dr. Orhan Öcalgiray Molecular Biology, Biotechnology and Genetics Research Center (İTÜ-MOBGAM), Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
| | - Zeynep Petek Çakar
- Department of Molecular Biology and Genetics, Faculty of Science & Letters, Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
- Dr. Orhan Öcalgiray Molecular Biology, Biotechnology and Genetics Research Center (İTÜ-MOBGAM), Istanbul Technical University, Maslak, Istanbul, 34469, Turkey
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23
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Ahangangoda Arachchige MS, Mizutani O, Toyama H. Yeast strains from coconut toddy in Sri Lanka show high tolerance to inhibitors derived from the hydrolysis of lignocellulosic materials. BIOTECHNOL BIOTEC EQ 2019. [DOI: 10.1080/13102818.2019.1676167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
| | - Osamu Mizutani
- United Graduate School of Agricultural Science, Kagoshima University, Kagoshima, Japan
- Department of Bioscience and Biotechnology, Faculty of Agriculture, University of the Ryukyus, Nishihara, Okinawa, Japan
| | - Hirohide Toyama
- United Graduate School of Agricultural Science, Kagoshima University, Kagoshima, Japan
- Department of Bioscience and Biotechnology, Faculty of Agriculture, University of the Ryukyus, Nishihara, Okinawa, Japan
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Cunha JT, Romaní A, Costa CE, Sá-Correia I, Domingues L. Molecular and physiological basis of Saccharomyces cerevisiae tolerance to adverse lignocellulose-based process conditions. Appl Microbiol Biotechnol 2018; 103:159-175. [PMID: 30397768 DOI: 10.1007/s00253-018-9478-3] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 10/19/2018] [Accepted: 10/22/2018] [Indexed: 11/27/2022]
Abstract
Lignocellulose-based biorefineries have been gaining increasing attention to substitute current petroleum-based refineries. Biomass processing requires a pretreatment step to break lignocellulosic biomass recalcitrant structure, which results in the release of a broad range of microbial inhibitors, mainly weak acids, furans, and phenolic compounds. Saccharomyces cerevisiae is the most commonly used organism for ethanol production; however, it can be severely distressed by these lignocellulose-derived inhibitors, in addition to other challenging conditions, such as pentose sugar utilization and the high temperatures required for an efficient simultaneous saccharification and fermentation step. Therefore, a better understanding of the yeast response and adaptation towards the presence of these multiple stresses is of crucial importance to design strategies to improve yeast robustness and bioconversion capacity from lignocellulosic biomass. This review includes an overview of the main inhibitors derived from diverse raw material resultants from different biomass pretreatments, and describes the main mechanisms of yeast response to their presence, as well as to the presence of stresses imposed by xylose utilization and high-temperature conditions, with a special emphasis on the synergistic effect of multiple inhibitors/stressors. Furthermore, successful cases of tolerance improvement of S. cerevisiae are highlighted, in particular those associated with other process-related physiologically relevant conditions. Decoding the overall yeast response mechanisms will pave the way for the integrated development of sustainable yeast cell-based biorefineries.
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Affiliation(s)
- Joana T Cunha
- Centre of Biological Engineering (CEB), University of Minho, 4710-057, Braga, Portugal
| | - Aloia Romaní
- Centre of Biological Engineering (CEB), University of Minho, 4710-057, Braga, Portugal
| | - Carlos E Costa
- Centre of Biological Engineering (CEB), University of Minho, 4710-057, Braga, Portugal
| | - Isabel Sá-Correia
- Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001, Lisbon, Portugal
| | - Lucília Domingues
- Centre of Biological Engineering (CEB), University of Minho, 4710-057, Braga, Portugal.
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Chen WH, Zeng YR. Mathematical model to appraise the inhibitory effect of phenolic compounds derived from lignin for biobutanol production. BIORESOURCE TECHNOLOGY 2018; 261:44-51. [PMID: 29653333 DOI: 10.1016/j.biortech.2018.04.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 03/30/2018] [Accepted: 04/02/2018] [Indexed: 06/08/2023]
Abstract
This study aimed to establish a mathematical modeling to evaluate the inhibitory effect of phenolic derivatives on acetone-butanol-ethanol (ABE) fermentation by Clostridium saccharoperbutylacetonicum N1-4. Vanillin, 4-hydroxybenzoic acid, and syringaldehyde were selected to represent guaiacyl, hydroxyphenyl, and syringyl phenols, respectively, to be examined in a series of fed-batch experiments. Results show the presence of phenolic derivatives blocked the pathway of the assimilation of organic acids and reduced cell growth and glucose utilization. The inhibition model projected that the levels of 0.13, 0.14, and 0.04 g L-1 for vanillin, 4-hydroxybenzoic acid, and syringaldehyde, respectively, resulted in 25% inhibition of butanol production, whereas 100% inhibition was predicted at the levels of 4.94, 4.37, and 4.20 g L-1 for vanillin, 4-hydroxybenzoic acid, and syringaldehyde, respectively. Syringaldehyde was more toxic than the other two compounds. The established model described that the phenolic compounds derived from different phenyl propane monomers of lignin severely obstructed biobutanol production.
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Affiliation(s)
- Wen-Hsing Chen
- Department of Environmental Engineering, National Ilan University, Yilan 260, Taiwan.
| | - Yan-Ru Zeng
- Department of Environmental Engineering, National Ilan University, Yilan 260, Taiwan
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26
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Martín C, Wu G, Wang Z, Stagge S, Jönsson LJ. Formation of microbial inhibitors in steam-explosion pretreatment of softwood impregnated with sulfuric acid and sulfur dioxide. BIORESOURCE TECHNOLOGY 2018; 262:242-250. [PMID: 29709843 DOI: 10.1016/j.biortech.2018.04.074] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 04/17/2018] [Accepted: 04/18/2018] [Indexed: 05/08/2023]
Abstract
Wood chips of Norway spruce were pretreated by steam explosion at 195-215 °C after impregnation with either sulfuric acid (SA) or sulfur dioxide (SD). The effects of different pretreatment conditions on formation of microbial inhibitors were investigated, and the inhibitory effects on yeast of pretreatment liquids and of specific inhibitors that were found in the pretreatment liquids were elucidated. Whereas the concentrations of most inhibitors increased with increasing pretreatment temperatures, there were exceptions, such as formaldehyde and p-hydroxybenzaldehyde. The highest concentration of each inhibitor was typically found in SD-pretreated material, but formic acid was an exception. The toxic effects on yeast were studied using concentrations corresponding to loadings of 12 and 20% total solids (TS). Among individual inhibitors that were quantitated in pretreatment liquids, the concentrations of formaldehyde were by far most toxic. There was no or minimal yeast growth in the formaldehyde concentration range (5.8-7.7 mM) corresponding to 12% TS.
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Affiliation(s)
- Carlos Martín
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
| | - Guochao Wu
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
| | - Zhao Wang
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
| | - Stefan Stagge
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
| | - Leif J Jönsson
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden.
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Su YK, Willis LB, Rehmann L, Smith DR, Jeffries TW. Spathaspora passalidarum selected for resistance to AFEX hydrolysate shows decreased cell yield. FEMS Yeast Res 2018; 18:5042277. [DOI: 10.1093/femsyr/foy011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 06/20/2018] [Indexed: 12/15/2022] Open
Affiliation(s)
- Yi-Kai Su
- Department of Biological Systems Engineering, University of Wisconsin, Madison, WI 53706, USA
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin, Madison, WI 53705, USA
- Forest Products Laboratory, USDA Forest Service, Madison, WI, 53726, USA
- Department of Chemical and Biochemical Engineering, University of Western Ontario, London, ON, N6A 3K, Canada
| | - Laura B Willis
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin, Madison, WI 53705, USA
- Forest Products Laboratory, USDA Forest Service, Madison, WI, 53726, USA
- Department of Bacteriology, University of Madison, WI, 53705, USA
| | - Lars Rehmann
- Department of Chemical and Biochemical Engineering, University of Western Ontario, London, ON, N6A 3K, Canada
| | - David R Smith
- Department of Biology, University of Western Ontario, London, ON, N6A 3K7, Canada
| | - Thomas W Jeffries
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin, Madison, WI 53705, USA
- Forest Products Laboratory, USDA Forest Service, Madison, WI, 53726, USA
- Department of Bacteriology, University of Madison, WI, 53705, USA
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28
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Bioethanol Production from Water Hyacinth Hydrolysate by Candida tropicalis Y-26. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2018. [DOI: 10.1007/s13369-018-3247-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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29
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Stanford JP, Hall PH, Rover MR, Smith RG, Brown RC. Separation of sugars and phenolics from the heavy fraction of bio-oil using polymeric resin adsorbents. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2017.11.040] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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30
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Sardi M, Paithane V, Place M, Robinson DE, Hose J, Wohlbach DJ, Gasch AP. Genome-wide association across Saccharomyces cerevisiae strains reveals substantial variation in underlying gene requirements for toxin tolerance. PLoS Genet 2018; 14:e1007217. [PMID: 29474395 PMCID: PMC5849340 DOI: 10.1371/journal.pgen.1007217] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 03/13/2018] [Accepted: 01/23/2018] [Indexed: 12/31/2022] Open
Abstract
Cellulosic plant biomass is a promising sustainable resource for generating alternative biofuels and biochemicals with microbial factories. But a remaining bottleneck is engineering microbes that are tolerant of toxins generated during biomass processing, because mechanisms of toxin defense are only beginning to emerge. Here, we exploited natural diversity in 165 Saccharomyces cerevisiae strains isolated from diverse geographical and ecological niches, to identify mechanisms of hydrolysate-toxin tolerance. We performed genome-wide association (GWA) analysis to identify genetic variants underlying toxin tolerance, and gene knockouts and allele-swap experiments to validate the involvement of implicated genes. In the process of this work, we uncovered a surprising difference in genetic architecture depending on strain background: in all but one case, knockout of implicated genes had a significant effect on toxin tolerance in one strain, but no significant effect in another strain. In fact, whether or not the gene was involved in tolerance in each strain background had a bigger contribution to strain-specific variation than allelic differences. Our results suggest a major difference in the underlying network of causal genes in different strains, suggesting that mechanisms of hydrolysate tolerance are very dependent on the genetic background. These results could have significant implications for interpreting GWA results and raise important considerations for engineering strategies for industrial strain improvement. Understanding the genetic architecture of complex traits is important for elucidating the genotype-phenotype relationship. Many studies have sought genetic variants that underlie phenotypic variation across individuals, both to implicate causal variants and to inform on architecture. Here we used genome-wide association analysis to identify genes and processes involved in tolerance of toxins found in plant-biomass hydrolysate, an important substrate for sustainable biofuel production. We found substantial variation in whether or not individual genes were important for tolerance across genetic backgrounds. Whether or not a gene was important in a given strain background explained more variation than the alleleic differences in the gene. These results suggest substantial variation in gene contributions, and perhaps underlying mechanisms, of toxin tolerance.
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Affiliation(s)
- Maria Sardi
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America.,Microbiology Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Vaishnavi Paithane
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Michael Place
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - De Elegant Robinson
- Microbiology Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - James Hose
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Dana J Wohlbach
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Audrey P Gasch
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America.,Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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Pinto ASS, Ribeiro MPA, Farinas CS. Fast spectroscopic monitoring of inhibitors in the 2G ethanol process. BIORESOURCE TECHNOLOGY 2018; 250:148-154. [PMID: 29161574 DOI: 10.1016/j.biortech.2017.11.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/09/2017] [Accepted: 11/10/2017] [Indexed: 05/22/2023]
Abstract
One of the main challenges of second generation (2G) ethanol production is the high quantities of phenolic compounds and furan derivatives generated in the pretreatment of the lignocellulosic biomass, which inhibit the enzymatic hydrolysis and fermentation steps. Fast monitoring of these inhibitory compounds could provide better control of the pretreatment, hydrolysis, and fermentation processes by enabling the implementation of strategic process control actions. We investigated the feasibility of monitoring these inhibitory compounds by ultraviolet-visible (UV-Vis) spectroscopy associated with partial least squares (PLS) regression. Hydroxymethylfurfural, furfural, vanillin, and ferulic and p-coumaric acids generated during different severities of liquid hot water pretreatment of sugarcane bagasse were quantified with highly accuracy. In cross-validation (leave-one-out), the PLS-UV-Vis method presented root mean square error of prediction (RMSECV) of around only 5.0%. The results demonstrated that the monitoring performance achieved with PLS-UV-Vis could support future studies of optimization and control protocols for application in industrial processes.
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Affiliation(s)
- Ariane S S Pinto
- Graduate Program of Chemical Engineering, Federal University of São Carlos, 13565-905, PO Box 676, São Carlos, SP, Brazil; Embrapa Instrumentation, Rua XV de Novembro 1452, 13560-970 São Carlos, SP, Brazil
| | - Marcelo P A Ribeiro
- Graduate Program of Chemical Engineering, Federal University of São Carlos, 13565-905, PO Box 676, São Carlos, SP, Brazil; Chemical Engineering Department, Federal University of São Carlos, 13565-905, PO Box 676, São Carlos, SP, Brazil
| | - Cristiane S Farinas
- Graduate Program of Chemical Engineering, Federal University of São Carlos, 13565-905, PO Box 676, São Carlos, SP, Brazil; Embrapa Instrumentation, Rua XV de Novembro 1452, 13560-970 São Carlos, SP, Brazil.
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32
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Lyra Colombi B, Silva Zanoni PR, Benathar Ballod Tavares L. Effect of phenolic compounds on bioconversion of glucose to ethanol by yeast Saccharomyces cerevisiae
PE-2. CAN J CHEM ENG 2018. [DOI: 10.1002/cjce.23114] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Wordofa GG, Kristensen M. Tolerance and metabolic response of Pseudomonas taiwanensis VLB120 towards biomass hydrolysate-derived inhibitors. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:199. [PMID: 30034525 PMCID: PMC6052574 DOI: 10.1186/s13068-018-1192-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 07/06/2018] [Indexed: 05/10/2023]
Abstract
BACKGROUND Bio-conversion of lignocellulosic biomass to high-value products offers numerous benefits; however, its development is hampered by chemical inhibitors generated during the pretreatment process. A better understanding of how microbes naturally respond to those inhibitors is valuable in the process of designing microorganisms with improved tolerance. Pseudomonas taiwanensis VLB120 is a natively tolerant strain that utilizes a wide range of carbon sources including pentose and hexose sugars. To this end, we investigated the tolerance and metabolic response of P. taiwanensis VLB120 towards biomass hydrolysate-derived inhibitors including organic acids (acetic acid, formic acid, and levulinic acid), furans (furfural, 5-hydroxymethylfurfural), and phenols (vanillin). RESULTS The inhibitory effect of the tested compounds varied with respect to lag phase, specific growth rate, and biomass yield compared to the control cultures grown under the same conditions without addition of inhibitors. However, P. taiwanensis was able to oxidize vanillin and furfural to vanillic acid and 2-furoic acid, respectively. Vanillic acid was further metabolized, whereas 2-furoic acid was secreted outside the cells and remained in the fermentation broth without further conversion. Acetic acid and formic acid were completely consumed from the fermentation broth, while concentration of levulinic acid remained constant throughout the fermentation process. Analysis of free intracellular metabolites revealed varying levels when P. taiwanensis VLB120 was exposed to inhibitory compounds. This resulted in increased levels of ATP to export inhibitors from the cell and NADPH/NADP ratio that provides reducing power to deal with the oxidative stress caused by the inhibitors. Thus, adequate supply of these metabolites is essential for the survival and reproduction of P. taiwanensis in the presence of biomass-derived inhibitors. CONCLUSIONS In this study, the tolerance and metabolic response of P. taiwanensis VLB120 to biomass hydrolysate-derived inhibitors was investigated. P. taiwanensis VLB120 showed high tolerance towards biomass hydrolysate-derived inhibitors compared to most wild-type microbes reported in the literature. It adopts different resistance mechanisms, including detoxification, efflux, and repair, which require additional energy and resources. Thus, targeting redox and energy metabolism in strain engineering may be a successful strategy to overcome inhibition during biomass hydrolysate conversion and lead to development of more robust strains.
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Affiliation(s)
- Gossa G. Wordofa
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Mette Kristensen
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800 Lyngby, Denmark
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Reifenrath M, Boles E. Engineering of hydroxymandelate synthases and the aromatic amino acid pathway enables de novo biosynthesis of mandelic and 4-hydroxymandelic acid with Saccharomyces cerevisiae. Metab Eng 2018; 45:246-254. [DOI: 10.1016/j.ymben.2018.01.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 12/12/2017] [Accepted: 01/07/2018] [Indexed: 10/18/2022]
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Deciphering the Origin, Evolution, and Physiological Function of the Subtelomeric Aryl-Alcohol Dehydrogenase Gene Family in the Yeast Saccharomyces cerevisiae. Appl Environ Microbiol 2017; 84:AEM.01553-17. [PMID: 29079624 PMCID: PMC5734042 DOI: 10.1128/aem.01553-17] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Accepted: 10/23/2017] [Indexed: 12/02/2022] Open
Abstract
Homology searches indicate that Saccharomyces cerevisiae strain BY4741 contains seven redundant genes that encode putative aryl-alcohol dehydrogenases (AAD). Yeast AAD genes are located in subtelomeric regions of different chromosomes, and their functional role(s) remain enigmatic. Here, we show that two of these genes, AAD4 and AAD14, encode functional enzymes that reduce aliphatic and aryl-aldehydes concomitant with the oxidation of cofactor NADPH, and that Aad4p and Aad14p exhibit different substrate preference patterns. Other yeast AAD genes are undergoing pseudogenization. The 5′ sequence of AAD15 has been deleted from the genome. Repair of an AAD3 missense mutation at the catalytically essential Tyr73 residue did not result in a functional enzyme. However, ancestral-state reconstruction by fusing Aad6 with Aad16 and by N-terminal repair of Aad10 restores NADPH-dependent aryl-alcohol dehydrogenase activities. Phylogenetic analysis indicates that AAD genes are narrowly distributed in wood-saprophyte fungi and in yeast that occupy lignocellulosic niches. Because yeast AAD genes exhibit activity on veratraldehyde, cinnamaldehyde, and vanillin, they could serve to detoxify aryl-aldehydes released during lignin degradation. However, none of these compounds induce yeast AAD gene expression, and Aad activities do not relieve aryl-aldehyde growth inhibition. Our data suggest an ancestral role for AAD genes in lignin degradation that is degenerating as a result of yeast's domestication and use in brewing, baking, and other industrial applications. IMPORTANCE Functional characterization of hypothetical genes remains one of the chief tasks of the postgenomic era. Although the first Saccharomyces cerevisiae genome sequence was published over 20 years ago, 22% of its estimated 6,603 open reading frames (ORFs) remain unverified. One outstanding example of this category of genes is the enigmatic seven-member AAD family. Here, we demonstrate that proteins encoded by two members of this family exhibit aliphatic and aryl-aldehyde reductase activity, and further that such activity can be recovered from pseudogenized AAD genes via ancestral-state reconstruction. The phylogeny of yeast AAD genes suggests that these proteins may have played an important ancestral role in detoxifying aromatic aldehydes in ligninolytic fungi. However, in yeast adapted to niches rich in sugars, AAD genes become subject to mutational erosion. Our findings shed new light on the selective pressures and molecular mechanisms by which genes undergo pseudogenization.
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Wu G, Xu Z, Jönsson LJ. Profiling of Saccharomyces cerevisiae transcription factors for engineering the resistance of yeast to lignocellulose-derived inhibitors in biomass conversion. Microb Cell Fact 2017; 16:199. [PMID: 29137634 PMCID: PMC5686817 DOI: 10.1186/s12934-017-0811-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 11/04/2017] [Indexed: 11/24/2022] Open
Abstract
Background Yeast transcription factors (TFs) involved in the regulation of multidrug resistance (MDR) were investigated in experiments with deletion mutants, transformants overexpressing synthetic genes encoding TFs, and toxic concentrations of lignocellulose-derived substances added to cultures as complex mixtures or as specific compounds, viz. coniferyl aldehyde, 5-hydroxymethylfurfural, and furfural. Results In the presence of complex mixtures of toxic substances from spruce wood, transformants overexpressing YAP1 and STB5, TFs involved in oxidative stress response, exhibited enhanced relative growth rates amounting to 4.589 ± 0.261 and 1.455 ± 0.185, respectively. Other TFs identified as important for resistance included DAL81, GZF3, LEU3, PUT3, and WAR1. Potential overlapping functions of YAP1 and STB5 were investigated in experiments with permutations of deletions and overexpression of the two genes. YAP1 complemented STB5 with respect to resistance to 5-hydroxymethylfurfural, but had a distinct role with regard to resistance to coniferyl aldehyde as deletion of YAP1 rendered the cell incapable of resisting coniferyl aldehyde even if STB5 was overexpressed. Conclusions We have investigated 30 deletion mutants and eight transformants overexpressing MDR transcription factors with regard to the roles the transcription factors play in the resistance to toxic concentrations of lignocellulose-derived substances. This work provides an overview of the involvement of thirty transcription factors in the resistance to lignocellulose-derived substances, shows distinct and complementary roles played by YAP1 and STB5, and offers directions for the engineering of robust yeast strains for fermentation processes based on lignocellulosic feedstocks.![]() Electronic supplementary material The online version of this article (10.1186/s12934-017-0811-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Guochao Wu
- Department of Chemistry, Umeå University, 901 87, Umeå, Sweden.
| | - Zixiang Xu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Leif J Jönsson
- Department of Chemistry, Umeå University, 901 87, Umeå, Sweden
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Mating of natural Saccharomyces cerevisiae strains for improved glucose fermentation and lignocellulosic inhibitor tolerance. Folia Microbiol (Praha) 2017; 63:155-168. [PMID: 28887734 DOI: 10.1007/s12223-017-0546-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 09/01/2017] [Indexed: 10/18/2022]
Abstract
Natural Saccharomyces cerevisiae isolates from vineyards in the Western Cape, South Africa were evaluated for ethanol production in industrial conditions associated with the production of second-generation biofuels. The strains displayed high phenotypic diversity including the ability to grow at 45 °C and in the presence of 20% (v/v) ethanol, strain YI13. Strains HR4 and YI30 were inhibitor-tolerant under aerobic and oxygen-limited conditions, respectively. Spore-to-spore hybridization generated progeny that displayed heterosis, including increased ethanol productivity and improved growth in the presence of a synthetic inhibitor cocktail. Hybrid strains HR4/YI30#6 and V3/YI30#6 were able to grow at a high salt concentration (2 mol/L NaCl) with V3/YI30#6 also able to grow at a high temperature (45 °C). Strains HR4/YI30#1 and #3 were inhibitor-tolerant, with strain HR4/YI30#3 having similar productivity (0.36 ± 0.0036 g/L per h) as the superior parental strain, YI30 (0.35 ± 0.0058 g/L per h). This study indicates that natural S. cerevisiae strains display phenotypic variation and heterosis can be achieved through spore-to-spore hybridization. Several of the phenotypes (temperature-, osmo-, and inhibitor tolerance) displayed by both the natural strains and the generated progeny were at the maximum conditions reported for S. cerevisiae strains.
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Mithra M, Padmaja G. Strategies for enzyme saving during saccharification of pretreated lignocellulo-starch biomass: effect of enzyme dosage and detoxification chemicals. Heliyon 2017; 3:e00384. [PMID: 28831456 PMCID: PMC5553344 DOI: 10.1016/j.heliyon.2017.e00384] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 05/22/2017] [Accepted: 08/07/2017] [Indexed: 11/25/2022] Open
Abstract
Two strategies leading to enzyme saving during saccharification of pretreated lignocellulo-starch biomass (LCSB) was investigated which included reducing enzyme dosage by varying their levels in enzyme cocktails and enhancing the fermentable sugar yield in enzyme-reduced systems using detoxification chemicals. Time course release of reducing sugars (RS) during 24-120 h was significantly higher when an enzyme cocktail containing full dose of cellulase (16 FPU/g cellulose) along with half dose each of xylanase (1.5 mg protein/g hemicelluloses) and Stargen (12.5 μl/g biomass) was used to saccharify conventional dilute sulphuric acid (DSA) pretreated biomass compared to a parallel system where only one-fourth the dose of the latter two enzymes was used. The reduction in RS content in the 120 h saccharified mash to the extent of 3-4 g/L compared to the system saccharified with full complement of the three enzymes could be overcome considerably by supplementing the system (half dose of two enzymes) with detoxification chemical mix incorporating Tween 20, PEG 4000 and sodium borohydride. Microwave (MW)-assisted DSA pretreated biomass on saccharification with enzyme cocktail having full dose of cellulase and half dose of Stargen along with detoxification chemicals gave significantly higher RS yield than DSA pretreated system saccharified using three enzymes. The study showed that xylanase could be eliminated during saccharification of MW-assisted DSA pretreated biomass without affecting RS yield when detoxification chemicals were also supplemented. The Saccharification Efficiency and Overall Conversion Efficiency were also high for the MW-assisted DSA pretreated biomass. Since whole slurry saccharifcation of pretreated biomass is essential to conserve fermentable sugars in LCSB saccharification, detoxification of soluble inhibitors is equally important as channelling out of insoluble lignin remaining in the residue. As one of the major factors contributing to the cost of ethanol production from LCSB is the cost of enzymes, appropriate modification of enzyme cocktail based on the composition of the pretreated biomass coupled with effective detoxification of the slurry would be a promising approach towards cost reduction.
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Affiliation(s)
| | - G. Padmaja
- Division of Crop Utilization, ICAR-Central Tuber Crops Research Institute, Thiruvananthapuram, Kerala, India
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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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Release of Polyphenols Is the Major Factor Influencing the Bioconversion of Rice Straw to Lactic Acid. Appl Biochem Biotechnol 2017; 183:685-698. [DOI: 10.1007/s12010-017-2457-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 03/12/2017] [Indexed: 10/19/2022]
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Qin L, Li X, Liu L, Zhu JQ, Guan QM, Zhang MT, Li WC, Li BZ, Yuan YJ. Dual effect of soluble materials in pretreated lignocellulose on simultaneous saccharification and co-fermentation process for the bioethanol production. BIORESOURCE TECHNOLOGY 2017; 224:342-348. [PMID: 27919544 DOI: 10.1016/j.biortech.2016.11.106] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 11/25/2016] [Accepted: 11/27/2016] [Indexed: 06/06/2023]
Abstract
In this study, wash liquors isolated from ethylenediamine and dry dilute acid pretreated corn stover were used to evaluate the effect of soluble materials in pretreated biomass on simultaneous saccharification and co-fermentation (SSCF) for ethanol production, respectively. Both of the wash liquors had different impacts on enzymatic hydrolysis and fermentation. Enzymatic conversions of glucan and xylan monotonically decreased as wash liquor concentration increased. Whereas, with low wash liquor concentrations, xylose consumption rate, cell viability and ethanol yield were maximally stimulated in fermentation without nutrient supplementary. Soluble lignins were found as the key composition which promoted sugars utilization and cell viability without nutrient supplementary. The dual effects of soluble materials on enzymatic hydrolysis and fermentation resulted in the reduction of ethanol yield as soluble materials increased in SSCF.
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Affiliation(s)
- Lei Qin
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China.
| | - Xia Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China.
| | - Li Liu
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China.
| | - Jia-Qing Zhu
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China.
| | - Qi-Man Guan
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China.
| | - Man-Tong Zhang
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China.
| | - Wen-Chao Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China.
| | - Bing-Zhi Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China.
| | - Ying-Jin Yuan
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China; SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Weijin Road 92, Nankai District, Tianjin 300072, PR China.
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Li J, Shi S, Adhikari S, Tu M. Inhibition effect of aromatic aldehydes on butanol fermentation by Clostridium acetobutylicum. RSC Adv 2017. [DOI: 10.1039/c6ra25706b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The ortho-substituted 2-hydroxybenzaldehyde caused 20-fold stronger inhibition than meta- and para-substituted analogues of 3- and 4-hydroxybenzaldehydes.
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Affiliation(s)
- Jing Li
- Department of Biosystems Engineering
- Auburn University
- USA
| | - Suan Shi
- Hawaii Natural Energy Institute
- University of Hawaii
- Honolulu
- USA
| | | | - Maobing Tu
- Department of Biomedical
- Chemical and Environmental Engineering
- University of Cincinnati
- Cincinnati
- USA
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Luque L, Oudenhoven S, Westerhof R, van Rossum G, Berruti F, Kersten S, Rehmann L. Comparison of ethanol production from corn cobs and switchgrass following a pyrolysis-based biorefinery approach. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:242. [PMID: 28702087 PMCID: PMC5505144 DOI: 10.1186/s13068-016-0661-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 11/01/2016] [Indexed: 06/07/2023]
Abstract
BACKGROUND One of the main obstacles in lignocellulosic ethanol production is the necessity of pretreatment and fractionation of the biomass feedstocks to produce sufficiently pure fermentable carbohydrates. In addition, the by-products (hemicellulose and lignin fraction) are of low value, when compared to dried distillers grains (DDG), the main by-product of corn ethanol. Fast pyrolysis is an alternative thermal conversion technology for processing biomass. It has recently been optimized to produce a stream rich in levoglucosan, a fermentable glucose precursor for biofuel production. Additional product streams might be of value to the petrochemical industry. However, biomass heterogeneity is known to impact the composition of pyrolytic product streams, as a complex mixture of aromatic compounds is recovered with the sugars, interfering with subsequent fermentation. The present study investigates the feasibility of fast pyrolysis to produce fermentable pyrolytic glucose from two abundant lignocellulosic biomass sources in Ontario, switchgrass (potential energy crop) and corn cobs (by-product of corn industry). RESULTS Demineralization of biomass removes catalytic centers and increases the levoglucosan yield during pyrolysis. The ash content of biomass was significantly decreased by 82-90% in corn cobs when demineralized with acetic or nitric acid, respectively. In switchgrass, a reduction of only 50% for both acids could be achieved. Conversely, levoglucosan production increased 9- and 14-fold in corn cobs when rinsed with acetic and nitric acid, respectively, and increased 11-fold in switchgrass regardless of the acid used. After pyrolysis, different configurations for upgrading the pyrolytic sugars were assessed and the presence of potentially inhibitory compounds was approximated at each step as double integral of the UV spectrum signal of an HPLC assay. The results showed that water extraction followed by acid hydrolysis and solvent extraction was the best upgrading strategy. Ethanol yields achieved based on initial cellulose fraction were 27.8% in switchgrass and 27.0% in corn cobs. CONCLUSIONS This study demonstrates that ethanol production from switchgrass and corn cobs is possible following a combined thermochemical and fermentative biorefinery approach, with ethanol yields comparable to results in conventional pretreatments and fermentation processes. The feedstock-independent fermentation ability can easily be assessed with a simple assay.
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Affiliation(s)
- Luis Luque
- Department of Chemical and Biochemical Engineering, University of Western Ontario, 1151 Richmond Street, London, ON Canada
- Institute for Chemicals and Fuels from Alternative Resources, University of Western Ontario, 22312 Wonderland Road, Ilderton, ON Canada
| | - Stijn Oudenhoven
- Sustainable Process Technology, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Roel Westerhof
- Sustainable Process Technology, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Guus van Rossum
- Shell Global Solutions International BV, P.O. Box 38000, 1030 BN Amsterdam, The Netherlands
| | - Franco Berruti
- Institute for Chemicals and Fuels from Alternative Resources, University of Western Ontario, 22312 Wonderland Road, Ilderton, ON Canada
| | - Sascha Kersten
- Sustainable Process Technology, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Lars Rehmann
- Department of Chemical and Biochemical Engineering, University of Western Ontario, 1151 Richmond Street, London, ON Canada
- Institute for Chemicals and Fuels from Alternative Resources, University of Western Ontario, 22312 Wonderland Road, Ilderton, ON Canada
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Pereira JPC, Verheijen PJT, Straathof AJJ. Growth inhibition of S. cerevisiae, B. subtilis, and E. coli by lignocellulosic and fermentation products. Appl Microbiol Biotechnol 2016; 100:9069-9080. [PMID: 27262569 PMCID: PMC5056951 DOI: 10.1007/s00253-016-7642-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 05/08/2016] [Accepted: 05/18/2016] [Indexed: 12/27/2022]
Abstract
This paper describes the effect of several inhibiting components on three potential hosts for the bio-based production of methyl propionate, namely, wild-type Escherichia coli and Bacillus subtilis, and evolved Saccharomyces cerevisiae IMS0351. The inhibition by the lignocellulose-derived products 5-hydroxymethyl-2-furaldehyde, vanillin, and syringaldehyde and the fermentation products 2-butanol, 2-butanone, methyl propionate, and ethyl acetate has been assessed for these strains in defined medium. Multiple screenings were performed using small-scale cultures in both shake flasks and microtiter plates. Technical drawbacks revealed the limited applicability of the latter in this study. The microbial growth was characterized by means of a lag-time model, and the inhibitory thresholds were determined using product-inhibition models. The lignocellulose-derived products were found to be highly inhibitory, and none of the strains could grow in the presence of 2.0 g L-1 of product. From the fermentation products tested, methyl propionate had the most severe impact resulting in complete inhibition of all the strains when exposed to concentrations in the range of 12-18 g L-1. In general, S. cerevisiae and B. subtilis were comparatively more tolerant than E. coli to all the fermentation products, despite E. coli's lower sensitivity towards vanillin. The results suggest that, overall, the strains investigated have good potential to be engineered and further established as hosts for the bio-based production of methyl esters.
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Affiliation(s)
- Joana P C Pereira
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ, Delft, the Netherlands
| | - Peter J T Verheijen
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ, Delft, the Netherlands
| | - Adrie J J Straathof
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ, Delft, the Netherlands.
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Kim D, Ximenes EA, Nichols NN, Cao G, Frazer SE, Ladisch MR. Maleic acid treatment of biologically detoxified corn stover liquor. BIORESOURCE TECHNOLOGY 2016; 216:437-445. [PMID: 27262718 DOI: 10.1016/j.biortech.2016.05.086] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 05/20/2016] [Accepted: 05/21/2016] [Indexed: 06/05/2023]
Abstract
Elimination of microbial and enzyme inhibitors from pretreated lignocellulose is critical for effective cellulose conversion and yeast fermentation of liquid hot water (LHW) pretreated corn stover. In this study, xylan oligomers were hydrolyzed using either maleic acid or hemicellulases, and other soluble inhibitors were eliminated by biological detoxification. Corn stover at 20% (w/v) solids was LHW pretreated LHW (severity factor: 4.3). The 20% solids (w/v) pretreated corn stover derived liquor was recovered and biologically detoxified using the fungus Coniochaeta ligniaria NRRL30616. After maleic acid treatment, and using 5 filter paper units of cellulase/g glucan (8.3mg protein/g glucan), 73% higher cellulose conversion from corn stover was obtained for biodetoxified samples compared to undetoxified samples. This corresponded to 87% cellulose to glucose conversion. Ethanol production by yeast of pretreated corn stover solids hydrolysate was 1.4 times higher than undetoxified samples, with a reduction of 3h in the fermentation lag phase.
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Affiliation(s)
- Daehwan Kim
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907-2032, United States; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907-2032, United States
| | - Eduardo A Ximenes
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907-2032, United States; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907-2032, United States
| | - Nancy N Nichols
- Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, USDA, 1815 N. University Street, Peoria, IL 61604, United States
| | - Guangli Cao
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150001, China
| | - Sarah E Frazer
- Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, USDA, 1815 N. University Street, Peoria, IL 61604, United States
| | - Michael R Ladisch
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907-2032, United States; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907-2032, United States; Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907-2032, United States.
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Ko JK, Um Y, Woo HM, Kim KH, Lee SM. Ethanol production from lignocellulosic hydrolysates using engineered Saccharomyces cerevisiae harboring xylose isomerase-based pathway. BIORESOURCE TECHNOLOGY 2016; 209:290-6. [PMID: 26990396 DOI: 10.1016/j.biortech.2016.02.124] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/25/2016] [Accepted: 02/26/2016] [Indexed: 05/12/2023]
Abstract
The efficient co-fermentation of glucose and xylose is necessary for the economically feasible bioethanol production from lignocellulosic biomass. Even with xylose utilizing Saccharomyces cerevisiae, the efficiency of the lignocellulosic ethanol production remains suboptimal mainly due to the low conversion yield of xylose to ethanol. In this study, we evaluated the co-fermentation performances of SXA-R2P-E, a recently engineered isomerase-based xylose utilizing strain, in mixed sugars and in lignocellulosic hydrolysates. In a high-sugar fermentation with 70g/L of glucose and 40g/L of xylose, SXA-R2P-E produced 50g/L of ethanol with an yield of 0.43gethanol/gsugars at 72h. From dilute acid-pretreated hydrolysates of rice straw and hardwood (oak), the strain produced 18-21g/L of ethanol with among the highest yield of 0.43-0.46gethanol/gsugars ever reported. This study shows a highly promising potential of a xylose isomerase-expressing strain as an industrially relevant ethanol producer from lignocellulosic hydrolysates.
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Affiliation(s)
- Ja Kyong Ko
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Youngsoon Um
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Han Min Woo
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Kyoung Heon Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul 02841, Republic of Korea
| | - Sun-Mi Lee
- Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.
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van der Pol EC, Vaessen E, Weusthuis RA, Eggink G. Identifying inhibitory effects of lignocellulosic by-products on growth of lactic acid producing micro-organisms using a rapid small-scale screening method. BIORESOURCE TECHNOLOGY 2016; 209:297-304. [PMID: 26990397 DOI: 10.1016/j.biortech.2016.03.037] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Revised: 03/04/2016] [Accepted: 03/05/2016] [Indexed: 05/14/2023]
Abstract
Sugars obtained from pretreated lignocellulose are interesting as substrate for the production of lactic acid in fermentation processes. However, by-products formed during pretreatment of lignocellulose can inhibit microbial growth. In this study, a small-scale rapid screening method was used to identify inhibitory effects of single and combined by-products on growth of lactic acid producing micro-organisms. The small-scale screening was performed in 48-well plates using 5 bacterial species and 12 by-products. Large differences were observed in inhibitory effects of by-products between different species. Predictions can be made for growth behaviour of different micro-organisms on acid pretreated or alkaline pretreated bagasse substrates using data from the small-scale screening. Both individual and combined inhibition effects were shown to be important parameters to predict growth. Synergy between coumaric acid, formic acid and acetic acid is a key inhibitory parameter in alkaline pretreated lignocellulose, while furfural is a key inhibitor in acid pretreated lignocellulose.
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Affiliation(s)
- Edwin C van der Pol
- Food and Biobased Research, Wageningen University and Research Centre, PO Box 17, 6700 AA Wageningen, Netherlands; Bioprocess Engineering, Wageningen University and Research Centre, PO Box 16, 6700 AA Wageningen, Netherlands.
| | - Evelien Vaessen
- Bioprocess Engineering, Wageningen University and Research Centre, PO Box 16, 6700 AA Wageningen, Netherlands
| | - Ruud A Weusthuis
- Bioprocess Engineering, Wageningen University and Research Centre, PO Box 16, 6700 AA Wageningen, Netherlands
| | - Gerrit Eggink
- Food and Biobased Research, Wageningen University and Research Centre, PO Box 17, 6700 AA Wageningen, Netherlands; Bioprocess Engineering, Wageningen University and Research Centre, PO Box 16, 6700 AA Wageningen, Netherlands
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48
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Jiang T, Qiao H, Zheng Z, Chu Q, Li X, Yong Q, Ouyang J. Lactic Acid Production from Pretreated Hydrolysates of Corn Stover by a Newly Developed Bacillus coagulans Strain. PLoS One 2016; 11:e0149101. [PMID: 26863012 PMCID: PMC4749344 DOI: 10.1371/journal.pone.0149101] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 01/27/2016] [Indexed: 01/20/2023] Open
Abstract
An inhibitor-tolerance strain, Bacillus coagulans GKN316, was developed through atmospheric and room temperature plasma (ARTP) mutation and evolution experiment in condensed dilute-acid hydrolysate (CDH) of corn stover. The fermentabilities of other hydrolysates with B. coagulans GKN316 and the parental strain B. coagulans NL01 were assessed. When using condensed acid-catalyzed steam-exploded hydrolysate (CASEH), condensed acid-catalyzed liquid hot water hydrolysate (CALH) and condensed acid-catalyzed sulfite hydrolysate (CASH) as substrates, the concentration of lactic acid reached 45.39, 16.83, and 18.71 g/L by B. coagulans GKN316, respectively. But for B. coagulans NL01, only CASEH could be directly fermented to produce 15.47 g/L lactic acid. The individual inhibitory effect of furfural, 5-hydroxymethylfurfural (HMF), vanillin, syringaldehyde and p-hydroxybenzaldehyde (pHBal) on xylose utilization by B. coagulans GKN316 was also studied. The strain B. coagulans GKN316 could effectively convert these toxic inhibitors to the less toxic corresponding alcohols in situ. These results suggested that B. coagulans GKN316 was well suited to production of lactic acid from undetoxified lignocellulosic hydrolysates.
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Affiliation(s)
- Ting Jiang
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People’s Republic of China
| | - Hui Qiao
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People’s Republic of China
| | - Zhaojuan Zheng
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People’s Republic of China
| | - Qiulu Chu
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People’s Republic of China
| | - Xin Li
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People’s Republic of China
| | - Qiang Yong
- Key Laboratory of Forest Genetics and Biotechnology of the Ministry of Education, Nanjing Forestry University, Nanjing, 210037, People’s Republic of China
| | - Jia Ouyang
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People’s Republic of China
- Key Laboratory of Forest Genetics and Biotechnology of the Ministry of Education, Nanjing Forestry University, Nanjing, 210037, People’s Republic of China
- * E-mail:
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Romero-García J, Martínez-Patiño C, Ruiz E, Romero I, Castro E. Ethanol production from olive stone hydrolysates by xylose fermenting microorganisms. ACTA ACUST UNITED AC 2016. [DOI: 10.1515/bioeth-2016-0002] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractOlive stones are the main solid byproducts obtained from olive oil production and from table olives production. As a lignocellulosic material, the use of olive stones for ethanol and other chemicals production has been proposed, particularly under the biorefinery concept. As part of such a process, this work deals with the fractionation of the lignocellulosic material by dilute acid autoclave pretreatment at 2% sulfuric acid, 130°C, 60 min and 1:1 liquid to solid ratio. Moreover, the work addresses the fermentation of the liquors obtained after pretreatment. The released sugars are composed mainly by xylose and other hemicellulosic sugars. The fermentation performance of three xylose-fermenting microorganisms, e.g. two Escherichia coli species and Scheffersomyces stipitis, are compared. The study analyzes in a first step the microorganism behavior on synthetic liquors, with a similar composition to that of the real liquors. Finally, and taken into account the results from the previous steps, the real liquor obtained from olive stones pretreatment is fermented. Results show that E. coli MM160 is the best ethanol producer out of the three microorganisms studied. Globally, the pretreatment produced a liquor containing 140 g hemicellulosic sugars/l and requiring firstly dilution by 50% and a detoxification step by overliming. The fermentation of this liquor by E. coli MM160 results in a 25 g ethanol/l solution equivalent to 50 g ethanol/kg olive stone, in spite of 20 g acetic acid/l also present. These results confirm both olive stones and E. coli MM160 as promising feedstock and microorganism for ethanol production.
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50
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Thompson OA, Hawkins GM, Gorsich SW, Doran-Peterson J. Phenotypic characterization and comparative transcriptomics of evolved Saccharomyces cerevisiae strains with improved tolerance to lignocellulosic derived inhibitors. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:200. [PMID: 27679668 PMCID: PMC5029107 DOI: 10.1186/s13068-016-0614-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 09/07/2016] [Indexed: 05/15/2023]
Abstract
BACKGROUND Lignocellulosic biomass continues to be investigated as a viable source for bioethanol production. However, the pretreatment process generates inhibitory compounds that impair the growth and fermentation performance of microorganisms such as Saccharomyces cerevisiae. Pinewood specifically has been shown to be challenging in obtaining industrially relevant ethanol titers. An industrial S. cerevisiae strain was subjected to directed evolution and adaptation in pretreated pine biomass and resultant strains, GHP1 and GHP4, exhibited improved growth and fermentative ability on pretreated pine in the presence of related inhibitory compounds. A comparative transcriptomic approach was applied to identify and characterize differences in phenotypic stability of evolved strains. RESULTS Evolved strains displayed different fermentative capabilities with pretreated pine that appear to be influenced by the addition or absence of 13 inhibitory compounds during pre-culturing. GHP4 performance was consistent independent of culturing conditions, while GHP1 performance was dependent on culturing with inhibitors. Comparative transcriptomics revealed 52 genes potentially associated with stress responses to multiple inhibitors simultaneously. Fluorescence microscopy revealed improved cellular integrity of both strains with mitochondria exhibiting resistance to the damaging effects of inhibitors in contrast to the parent. CONCLUSIONS Multiple potentially novel genetic targets have been discovered for understanding stress tolerance through the characterization of our evolved strains. This study specifically examines the synergistic effects of multiple inhibitors and identified targets will guide future studies in remediating effects of inhibitors and further development of robust yeast strains for multiple industrial applications.
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Affiliation(s)
| | - Gary M. Hawkins
- Department of Microbiology, University of Georgia, Athens, GA 30602 USA
| | - Steven W. Gorsich
- Department of Biology, Central Michigan University, Mount Pleasant, MI 48859 USA
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