1
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Guo Y, Askari N, Smets I, Appels L. A review on co-metabolic degradation of organic micropollutants during anaerobic digestion: Linkages between functional groups and digestion stages. WATER RESEARCH 2024; 256:121598. [PMID: 38663209 DOI: 10.1016/j.watres.2024.121598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 03/13/2024] [Accepted: 04/09/2024] [Indexed: 05/12/2024]
Abstract
The emerging presence of organic micropollutants (OMPs) in water bodies produced by human activities is a source of growing concern due to their environmental and health issues. Biodegradation is a widely employed treatment method for OMPs in wastewater owing to its high efficiency and low operational cost. Compared to aerobic degradation, anaerobic degradation has numerous advantages, including energy efficiency and superior performance for certain recalcitrant compounds. Nonetheless, the low influent concentrations of OMPs in wastewater treatment plants (WWTPs) and their toxicity make it difficult to support the growth of microorganisms. Therefore, co-metabolism is a promising mechanism for OMP biodegradation in which co-substrates are added as carbon and energy sources and stimulate increased metabolic activity. Functional microorganisms and enzymes exhibit significant variations at each stage of anaerobic digestion affecting the environment for the degradation of OMPs with different structural properties, as these factors substantially influence OMPs' biodegradability and transformation pathways. However, there is a paucity of literature reviews that explicate the correlations between OMPs' chemical structure and specific metabolic conditions. This study provides a comprehensive review of the co-metabolic processes which are favored by each stage of anaerobic digestion and attempts to link various functional groups to their favorable degradation pathways. Furthermore, potential co-metabolic processes and strategies that can enhance co-digestion are also identified, providing directions for future research.
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Affiliation(s)
- Yutong Guo
- KU Leuven, Department of Chemical Engineering, Chemical and Biochemical Reactor Engineering and Safety (CREaS) Campus De Nayer, Jan Pieter De Nayerlaan 5, Sint-Katelijne-Waver 2860, Belgium
| | - Najmeh Askari
- KU Leuven, Department of Chemical Engineering, Chemical and Biochemical Reactor Engineering and Safety (CREaS) Campus De Nayer, Jan Pieter De Nayerlaan 5, Sint-Katelijne-Waver 2860, Belgium
| | - Ilse Smets
- KU Leuven, Department of Chemical Engineering, Chemical and Biochemical Reactor Engineering and Safety (CREaS), Celestijnenlaan 200F box 2424, Heverlee 3001, Belgium
| | - Lise Appels
- KU Leuven, Department of Chemical Engineering, Chemical and Biochemical Reactor Engineering and Safety (CREaS) Campus De Nayer, Jan Pieter De Nayerlaan 5, Sint-Katelijne-Waver 2860, Belgium.
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2
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Xu B, Zhang W, Zhao E, Hong J, Chen X, Wei Z, Li X. Unveiling malic acid biorefinery: Comprehensive insights into feedstocks, microbial strains, and metabolic pathways. BIORESOURCE TECHNOLOGY 2024; 394:130265. [PMID: 38160850 DOI: 10.1016/j.biortech.2023.130265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/24/2023] [Accepted: 12/25/2023] [Indexed: 01/03/2024]
Abstract
The over-reliance on fossil fuels and resultant environmental issues necessitate sustainable alternatives. Microbial fermentation of biomass for malic acid production offers a viable, eco-friendly solution, enhancing resource efficiency and minimizing ecological damage. This review covers three core aspects of malic acid biorefining: feedstocks, microbial strains, and metabolic pathways. It emphasizes the significance of utilizing biomass sugars, including the co-fermentation of different sugar types to improve feedstock efficiency. The review discusses microbial strains for malic acid fermentation, addressing challenges related to by-products from biomass breakdown and strategies for overcoming them. It delves into the crucial pathways and enzymes for malic acid production, outlining methods to optimize its metabolism, focusing on enzyme regulation, energy balance, and yield enhancement. These insights contribute to advancing the field of consolidated bioprocessing in malic acid biorefining.
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Affiliation(s)
- Boyang Xu
- Anhui Fermented Food Engineering Research Center, School of Food and Biological Engineering, Hefei University of Technology, Hefei City 230009, Anhui Province, PR China
| | - Wangwei Zhang
- Anhui Fermented Food Engineering Research Center, School of Food and Biological Engineering, Hefei University of Technology, Hefei City 230009, Anhui Province, PR China
| | - Eryong Zhao
- Anhui Fermented Food Engineering Research Center, School of Food and Biological Engineering, Hefei University of Technology, Hefei City 230009, Anhui Province, PR China
| | - Jiong Hong
- School of Life Sciences, University of Science and Technology of China, Hefei City 230026, Anhui Province, PR China
| | - Xiangsong Chen
- Institute of Plasma Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei City 230031, Anhui Province, PR China
| | - Zhaojun Wei
- School of Biological Sciences and Engineering, North Minzu University, Yinchuan City 750030, Ningxia Hui Autonomous Region, PR China.
| | - Xingjiang Li
- Anhui Fermented Food Engineering Research Center, School of Food and Biological Engineering, Hefei University of Technology, Hefei City 230009, Anhui Province, PR China.
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3
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Li Y, Wang H, Zhang Y, Xiang Q, Chen Q, Yu X, Zhang L, Peng W, Penttinen P, Gu Y. Hydrated lime promoted the polysaccharide content and affected the transcriptomes of Lentinula edodes during brown film formation. Front Microbiol 2023; 14:1290180. [PMID: 38111638 PMCID: PMC10726012 DOI: 10.3389/fmicb.2023.1290180] [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: 09/07/2023] [Accepted: 11/13/2023] [Indexed: 12/20/2023] Open
Abstract
Brown film formation, a unique developmental stage in the life cycle of Lentinula edodes, is essential for the subsequent development of fruiting bodies in L. edodes cultivation. The pH of mushroom growth substrates are usually adjusted with hydrated lime, yet the effects of hydrated lime on cultivating L. edodes and the molecular mechanisms associated with the effects have not been studied systemically. We cultivated L. edodes on substrates supplemented with 0% (CK), 1% (T1), 3% (T2), and 5% (T3) hydrated lime (Ca (OH)2), and applied transcriptomics and qRT-PCR to study gene expression on the brown film formation stage. Hydrated lime increased polysaccharide contents in L. edodes, especially in T2, where the 5.3% polysaccharide content was approximately 1.5 times higher than in the CK. The addition of hydrated lime in the substrate promoted laccase, lignin peroxidase and manganese peroxidase activities, implying that hydrated lime improved the ability of L. edodes to decompose lignin and provide nutrition for its growth and development. Among the annotated 9,913 genes, compared to the control, 47 genes were up-regulated and 52 genes down-regulated in T1; 73 genes were up-regulated and 44 were down-regulated in T2; and 125 genes were up-regulated and 65 genes were down-regulated in T3. Differentially expressed genes (DEGs) were enriched in the amino acid metabolism, lipid metabolism and carbohydrate metabolism related pathways. The carbohydrate-active enzyme genes up-regulated in the hydrated lime treatments were mostly glycosyl hydrolase genes. The results will facilitate future optimization of L. edodes cultivation techniques and possibly shortening the production cycle.
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Affiliation(s)
- Yan Li
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Hongcheng Wang
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Ying Zhang
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Quanju Xiang
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Qiang Chen
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Xiumei Yu
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Lingzi Zhang
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Weihong Peng
- Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Petri Penttinen
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Yunfu Gu
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
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4
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Qi L, Zhu YX, Wang YK, Tang XX, Li KJ, He M, Sui Y, Wang PM, Zheng DQ, Zhang K. Nonlethal Furfural Exposure Causes Genomic Alterations and Adaptability Evolution in Saccharomyces cerevisiae. Microbiol Spectr 2023; 11:e0121623. [PMID: 37395645 PMCID: PMC10434202 DOI: 10.1128/spectrum.01216-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 06/09/2023] [Indexed: 07/04/2023] Open
Abstract
Furfural is a major inhibitor found in lignocellulosic hydrolysate, a promising feedstock for the biofermentation industry. In this study, we aimed to investigate the potential impact of this furan-derived chemical on yeast genome integrity and phenotypic evolution by using genetic screening systems and high-throughput analyses. Our results showed that the rates of aneuploidy, chromosomal rearrangements (including large deletions and duplications), and loss of heterozygosity (LOH) increased by 50-fold, 23-fold, and 4-fold, respectively, when yeast cells were cultured in medium containing a nonlethal dose of furfural (0.6 g/L). We observed significantly different ratios of genetic events between untreated and furfural-exposed cells, indicating that furfural exposure induced a unique pattern of genomic instability. Furfural exposure also increased the proportion of CG-to-TA and CG-to-AT base substitutions among point mutations, which was correlated with DNA oxidative damage. Interestingly, although monosomy of chromosomes often results in the slower growth of yeast under spontaneous conditions, we found that monosomic chromosome IX contributed to the enhanced furfural tolerance. Additionally, terminal LOH events on the right arm of chromosome IV, which led to homozygosity of the SSD1 allele, were associated with furfural resistance. This study sheds light on the mechanisms underlying the influence of furfural on yeast genome integrity and adaptability evolution. IMPORTANCE Industrial microorganisms are often exposed to multiple environmental stressors and inhibitors during their application. This study demonstrates that nonlethal concentrations of furfural in the culture medium can significantly induce genome instability in the yeast Saccharomyces cerevisiae. Notably, furfural-exposed yeast cells displayed frequent chromosome aberrations, indicating the potent teratogenicity of this inhibitor. We identified specific genomic alterations, including monosomic chromosome IX and loss of heterozygosity of the right arm of chromosome IV, that confer furfural tolerance to a diploid S. cerevisiae strain. These findings enhance our understanding of how microorganisms evolve and adapt to stressful environments and offer insights for developing strategies to improve their performance in industrial applications.
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Affiliation(s)
- Lei Qi
- Donghai Laboratory, Zhoushan, China
- Ocean College, Zhejiang University, Zhoushan, China
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | | | - Ye-Ke Wang
- Life Sciences Institute, Zhejiang University, Hangzhou, China
| | | | - Ke-Jing Li
- Ocean College, Zhejiang University, Zhoushan, China
| | - Min He
- Ocean College, Zhejiang University, Zhoushan, China
| | - Yang Sui
- Donghai Laboratory, Zhoushan, China
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina, USA
| | - Pin-Mei Wang
- Donghai Laboratory, Zhoushan, China
- Ocean College, Zhejiang University, Zhoushan, China
| | - Dao-Qiong Zheng
- Donghai Laboratory, Zhoushan, China
- Ocean College, Zhejiang University, Zhoushan, China
| | - Ke Zhang
- College of Life Science, Zhejiang University, Hangzhou, China
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5
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Wagner ER, Gasch AP. Advances in S. cerevisiae Engineering for Xylose Fermentation and Biofuel Production: Balancing Growth, Metabolism, and Defense. J Fungi (Basel) 2023; 9:786. [PMID: 37623557 PMCID: PMC10455348 DOI: 10.3390/jof9080786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 07/19/2023] [Accepted: 07/24/2023] [Indexed: 08/26/2023] Open
Abstract
Genetically engineering microorganisms to produce chemicals has changed the industrialized world. The budding yeast Saccharomyces cerevisiae is frequently used in industry due to its genetic tractability and unique metabolic capabilities. S. cerevisiae has been engineered to produce novel compounds from diverse sugars found in lignocellulosic biomass, including pentose sugars, like xylose, not recognized by the organism. Engineering high flux toward novel compounds has proved to be more challenging than anticipated since simply introducing pathway components is often not enough. Several studies show that the rewiring of upstream signaling is required to direct products toward pathways of interest, but doing so can diminish stress tolerance, which is important in industrial conditions. As an example of these challenges, we reviewed S. cerevisiae engineering efforts, enabling anaerobic xylose fermentation as a model system and showcasing the regulatory interplay's controlling growth, metabolism, and stress defense. Enabling xylose fermentation in S. cerevisiae requires the introduction of several key metabolic enzymes but also regulatory rewiring of three signaling pathways at the intersection of the growth and stress defense responses: the RAS/PKA, Snf1, and high osmolarity glycerol (HOG) pathways. The current studies reviewed here suggest the modulation of global signaling pathways should be adopted into biorefinery microbial engineering pipelines to increase efficient product yields.
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Affiliation(s)
- Ellen R. Wagner
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI 53706, USA
- Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Audrey P. Gasch
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI 53706, USA
- Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI 53706, USA
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6
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Abrha GT, Li Q, Kuang X, Xiao D, Ayepa E, Wu J, Chen H, Zhang Z, Liu Y, Yu X, Xiang Q, Ma M. Contribution of YPRO15C Overexpression to the Resistance of Saccharomyces cerevisiae BY4742 Strain to Furfural Inhibitor. Pol J Microbiol 2023; 72:177-186. [PMID: 37314359 DOI: 10.33073/pjm-2023-019] [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: 02/09/2023] [Accepted: 04/13/2023] [Indexed: 06/15/2023] Open
Abstract
Lignocellulosic biomass is still considered a feasible source of bioethanol production. Saccharomyces cerevisiae can adapt to detoxify lignocellulose-derived inhibitors, including furfural. Tolerance of strain performance has been measured by the extent of the lag phase for cell proliferation following the furfural inhibitor challenge. The purpose of this work was to obtain a tolerant yeast strain against furfural through overexpression of YPR015C using the in vivo homologous recombination method. The physiological observation of the overexpressing yeast strain showed that it was more resistant to furfural than its parental strain. Fluorescence microscopy revealed improved enzyme reductase activity and accumulation of oxygen reactive species due to the harmful effects of furfural inhibitor in contrast to its parental strain. Comparative transcriptomic analysis revealed 79 genes potentially involved in amino acid biosynthesis, oxidative stress, cell wall response, heat shock protein, and mitochondrial-associated protein for the YPR015C overexpressing strain associated with stress responses to furfural at the late stage of lag phase growth. Both up- and down-regulated genes involved in diversified functional categories were accountable for tolerance in yeast to survive and adapt to the furfural stress in a time course study during the lag phase growth. This study enlarges our perceptions comprehensively about the physiological and molecular mechanisms implicated in the YPR015C overexpressing strain's tolerance under furfural stress. Construction illustration of the recombinant plasmid. a) pUG6-TEF1p-YPR015C, b) integration diagram of the recombinant plasmid pUG6-TEF1p-YPR into the chromosomal DNA of Saccharomyces cerevisiae.
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Affiliation(s)
- Getachew Tafere Abrha
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
- 3Department of Biotechnology, College of Dry Land Agriculture and Natural Resources, Mekelle University, Mekelle, Ethiopia
| | - Qian Li
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
| | - Xiaolin Kuang
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
| | - Difan Xiao
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
| | - Ellen Ayepa
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
| | - Jinjian Wu
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
| | - Huan Chen
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
| | - Zhengyue Zhang
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
| | - Yina Liu
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
| | - Xiumei Yu
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
| | - Quanju Xiang
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
| | - Menggen Ma
- 1Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Sichuan, China
- 2Institute of Natural Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, Sichuan, China
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Identification of a Novel Dehydrogenase from Gluconobacter oxydans for Degradation of Inhibitors Derived from Lignocellulosic Biomass. FERMENTATION-BASEL 2023. [DOI: 10.3390/fermentation9030286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
Abstract
Inhibitors from lignocellulosic biomass have become the bottleneck of biorefinery development. Gluconobacter oxydans DSM2003 showed a high performance of inhibitors degradation, which had a short lag time in non-detoxified corn stover hydrolysate and could convert 90% of aldehyde inhibitors to weaker toxic acids. In this study, an aldehyde dehydrogenase gene W826-RS0111485, which plays an important function in the conversion of aldehyde inhibitors in Gluconobacter oxydans DSM2003, was identified. W826-RS0111485 was found by protein profiling, then a series of enzymatic properties were determined and were heterologously expressed in E. coli. The results indicated that NADP is the most suitable cofactor of the enzyme when aldehyde inhibitor is the substrate, and it had the highest oxidation activity to furfural among several aldehyde inhibitors. Under the optimal reaction conditions (50 °C, pH 7.5), the Km and Vmax of the enzyme under furfural stress were 2.45 and 80.97, respectively, and the Kcat was 232.22 min−1. The biodetoxification performance experiments showed that the recombinant E. coli containing the target gene completely converted 1 g/L furfural to furoic acid within 8 h, while the control E. coli only converted 18% furfural within 8 h. It was further demonstrated that W826-RS0111485 played an important role in the detoxification of furfural. The mining of this inhibitor degradation gene could provide a theoretical basis for rational modification of industrial strains to enhance its capacity of inhibitor degradation in the future.
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8
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Homo- and heterofermentative lactobacilli are distinctly affected by furanic compounds. Biotechnol Lett 2022; 44:1431-1445. [DOI: 10.1007/s10529-022-03310-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 08/24/2022] [Accepted: 10/05/2022] [Indexed: 11/07/2022]
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9
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Metabolization of the glycation compounds 3-deoxyglucosone and 5-hydroxymethylfurfural by Saccharomyces yeasts. Eur Food Res Technol 2022. [DOI: 10.1007/s00217-022-04137-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractThe Maillard reaction products (MRPs) 3-deoxyglucosone (3-DG) and 5-hydroxymethylfurfural (HMF), which are formed during the thermal processing and storage of food, come into contact with technologically used yeasts during the fermentation of beer and wine. In order for the yeast cells to work efficiently, handling of the stress-inducing carbonyl compounds is essential. In the present study, the utilization of 3-DG and HMF by 13 Saccharomyces yeast strains (7 brewer’s yeast strains, 1 wine yeast strain, 6 yeast strains isolated from natural habitats) was investigated. All yeast strains studied were able to metabolize 3-DG and HMF. 3-DG is mainly reduced to 3-deoxyfructose (3-DF) and HMF is completely converted to 2,5-bishydroxymethylfuran (BHMF) and 5-formyl-2-furancarboxylic acid (FFCA). The ratio of conversion of HMF to BHMF and FFCA was found to be yeast strain-specific and no differences in the HMF stress tolerance of the yeast strains and species were observed. After incubation with 3-DG, varying amounts of intra- and extracellular 3-DF were found, pointing to a faster transport of 3-DG into the cells in the case of brewer’s yeast strains. Furthermore, the brewer’s yeast strains showed a significantly higher 3-DG stress resistance than the investigated yeast strains isolated from natural habitats. Thus, it can be shown for the first time that Saccharomyces yeast strains differ in their interaction of 3-DG induced carbonyl stress.
Graphical abstract
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10
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Liu ZL, Huang X. Copy number variants impact phenotype-genotype relationships for adaptation of industrial yeast Saccharomyces cerevisiae. Appl Microbiol Biotechnol 2022; 106:6611-6623. [PMID: 36117206 DOI: 10.1007/s00253-022-12137-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 05/24/2022] [Accepted: 08/17/2022] [Indexed: 11/29/2022]
Abstract
The industrial yeast Saccharomyces cerevisiae possesses a plastic genome enabling its adaptation to varied environment conditions. A more robust ethanologenic industrial yeast strain NRRL Y-50049 was obtained through laboratory adaptation that is resistant to 2-furaldehyde (furfural) and 5-hydroxymethyl-2-furaldehyde (HMF), a major class of toxic chemicals associated with lignocellulose-to-biofuel conversion. A significant amount of knowledge has been achieved in characterizing its tolerant phenotypes and molecular mechanisms of the resistance. Recent findings on a limited number of nonsynonymous SNP (single nucleotide polymorphism) detected in NRRL Y-50049 compared with its progenitor NRRL Y-12632 raised doubt of SNP roles in the tolerance adaptation. The genotype-phenotype relationship for yeast adaptation to the toxic chemicals is yet unclear. Here, we examine copy number variant (CNV) of the adapted strain NRRL Y-50049 to address phenotype-genotype relationships. As a background information, CNV of model strain S288C of the reference genome was also examined versus the industrial-type strain NRRL Y-12632. More than 200 CNVs, mostly duplication events, were detected in NRRL Y-12632 compared with the laboratory model strain S288C. Such enriched genetic background supports its more diversified phenotype response for the industrial yeast than the laboratory strain S288C. Comparing the two industrial strains, we found extra nine CNVs in the mitochondrial genome and 28 CNVs in the nuclear genome of NRRL Y-50049 versus its progenitor NRRL Y-12632. Continued DNA recombination event and high rate of CNV observed in NRRL Y-50049 versus its progenitor suggests that CNV is more impactful than SNP in association with phenotype-genotype relationships of yeast adaptation to the toxic chemical stress. COX1 and COB loci were defined as DNA recombination hotspots in the mitochondrial genome for the industrial yeast based on the high frequency of CNVs observed in these loci. KEY POINTS: • COX1 and COB loci are identified as DNA recombination hotspots for the industrial yeast. • The industrial yeast type strain NRRL Y-12632 possesses more CNVs vs the reference genome S288C. • CNV is more important than SNP on phenotype-genotype relationships for yeast adaptation.
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Affiliation(s)
- Z Lewis Liu
- Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, USDA, 1815 N. University Street, Peoria, IL, 61604, USA.
| | - Xiaoqiu Huang
- Department of Computer Science, Iowa State University, Ames, IA, 50011, USA
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11
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Vanacloig-Pedros E, Fisher KJ, Liu L, Debrauske DJ, Young MKM, Place M, Hittinger CT, Sato TK, Gasch AP. Comparative chemical genomic profiling across plant-based hydrolysate toxins reveals widespread antagonism in fitness contributions. FEMS Yeast Res 2022; 21:6650360. [PMID: 35883225 PMCID: PMC9508847 DOI: 10.1093/femsyr/foac036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 07/06/2022] [Accepted: 07/21/2022] [Indexed: 11/15/2022] Open
Abstract
The budding yeast Saccharomyces cerevisiae has been used extensively in fermentative industrial processes, including biofuel production from sustainable plant-based hydrolysates. Myriad toxins and stressors found in hydrolysates inhibit microbial metabolism and product formation. Overcoming these stresses requires mitigation strategies that include strain engineering. To identify shared and divergent mechanisms of toxicity and to implicate gene targets for genetic engineering, we used a chemical genomic approach to study fitness effects across a library of S. cerevisiae deletion mutants cultured anaerobically in dozens of individual compounds found in different types of hydrolysates. Relationships in chemical genomic profiles identified classes of toxins that provoked similar cellular responses, spanning inhibitor relationships that were not expected from chemical classification. Our results also revealed widespread antagonistic effects across inhibitors, such that the same gene deletions were beneficial for surviving some toxins but detrimental for others. This work presents a rich dataset relating gene function to chemical compounds, which both expands our understanding of plant-based hydrolysates and provides a useful resource to identify engineering targets.
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Affiliation(s)
- Elena Vanacloig-Pedros
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 53726, Madison, WI, United States
| | - Kaitlin J Fisher
- Laboratory of Genetics, University of Wisconsin-Madison, 53706, Madison, WI, United States
- Center for Genomic Science Innovation, University of Wisconsin-Madison, 53706, Madison, WI, United States
- J.F. Crow Institute for the Study of Evolution, 53706, Madison, WI, United States
| | - Lisa Liu
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 53726, Madison, WI, United States
| | - Derek J Debrauske
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 53726, Madison, WI, United States
| | - Megan K M Young
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 53726, Madison, WI, United States
| | - Michael Place
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 53726, Madison, WI, United States
| | - Chris Todd Hittinger
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 53726, Madison, WI, United States
- Laboratory of Genetics, University of Wisconsin-Madison, 53706, Madison, WI, United States
- Center for Genomic Science Innovation, University of Wisconsin-Madison, 53706, Madison, WI, United States
- J.F. Crow Institute for the Study of Evolution, 53706, Madison, WI, United States
| | - Trey K Sato
- Corresponding author: Trey K. Sato, Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 4117 Wisconsin Energy Institute, 1552 University Ave, Madison, WI 53726. Tel: (608) 890-2546; E-mail:
| | - Audrey P Gasch
- Corresponding author: Audrey P. Gasch, Center for Genomic Science Innovation, University of Wisconsin-Madison, 3422 Genetics-Biotechnology Center, 425 Henry Mall, Madison, WI 53704, United States. Tel: (608)265-0859; E-mail:
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12
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Lima CS, Neitzel T, Pirolla R, Dos Santos LV, Lenczak JL, Roberto IC, Rocha GJM. Metabolomic profiling of Spathaspora passalidarum fermentations reveals mechanisms that overcome hemicellulose hydrolysate inhibitors. Appl Microbiol Biotechnol 2022; 106:4075-4089. [PMID: 35622124 DOI: 10.1007/s00253-022-11987-y] [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: 08/09/2021] [Revised: 04/21/2022] [Accepted: 05/17/2022] [Indexed: 11/30/2022]
Abstract
Understanding the mechanisms involved in tolerance to inhibitors is the first step in developing robust yeasts for industrial second-generation ethanol (E2G) production. Here, we used ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) and MetaboAnalyst 4.0 for analysis of MS data to examine the changes in the metabolic profile of the yeast Spathaspora passalidarum during early fermentation of hemicellulosic hydrolysates containing high or low levels of inhibitors (referred to as control hydrolysate or CH and strategy hydrolysate or SH, respectively). During fermentation of SH, the maximum ethanol production was 16 g L-1 with a yield of 0.28 g g-1 and productivity of 0.22 g L-1 h-1, whereas maximum ethanol production in CH fermentation was 1.74 g L-1 with a yield of 0.11 g g-1 and productivity of 0.01 g L-1 h-1. The high level of inhibitors in CH induced complex physiological and biochemical responses related to stress tolerance in S. passalidarum. This yeast converted compounds with aldehyde groups (hydroxymethylfurfural, furfural, 4-hydroxybenzaldehyde, syringaldehyde, and vanillin) into less toxic compounds, and inhibitors were found to reduce cell viability and ethanol production. Intracellularly, high levels of inhibitors altered the energy homeostasis and redox balance, resulting in lower levels of ATP and NADPH, while that of glycolytic, pentose phosphate, and tricarboxylic acid (TCA) cycle pathways were the most affected, being the catabolism of glucogenic amino acids, the main cellular response to inhibitor-induced stress. This metabolomic investigation reveals interesting targets for metabolic engineering of ethanologenic yeast strains tolerant against multiple inhibitors for E2G production. KEY POINTS: • Inhibitors in the hydrolysates affected the yeast's redox balance and energy status. • Inhibitors altered the glycolytic, pentose phosphate, TCA cycle and amino acid pathways. • S. passalidarum converted aldehyde groups into less toxic compounds.
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Affiliation(s)
- Cleilton Santos Lima
- Department of Biotechnology, Engineering College of Lorena, University of São Paulo (USP), Estrada Municipal Do Campinho, s/n, Campinho, Lorena, SP, 12602-810, Brazil. .,Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Rua Giuseppe Máximo Scolfaro 10.000, Campinas, SP, 13083-100, Brazil.
| | - Thiago Neitzel
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Rua Giuseppe Máximo Scolfaro 10.000, Campinas, SP, 13083-100, Brazil.,Program in Bioenergy, Faculty of Food Engineering, State University of Campinas (UNICAMP), Rua Monteiro Lobato 80, Campinas, SP, 13083-862, Brazil
| | - Renan Pirolla
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Rua Giuseppe Máximo Scolfaro 10.000, Campinas, SP, 13083-100, Brazil
| | - Leandro Vieira Dos Santos
- Senai Innovation Institute for Biotechnology, São Paulo, SP, 01130-000, Brazil.,Genetics and Molecular Biology Graduate Program, Institute of Biology, State University of Campinas (UNICAMP), Rua Monteiro Lobato 255, Campinas, 13083-862, Brazil
| | - Jaciane Lutz Lenczak
- Department of Chemical Engineering and Food Engineering, University Campus - CTC, Federal University of Santa Catarina (UFSC), R. Do Biotério Central, Córrego Grande, s/n Florianópolis, SC, 88040-900, Brazil
| | - Inês Conceição Roberto
- Department of Biotechnology, Engineering College of Lorena, University of São Paulo (USP), Estrada Municipal Do Campinho, s/n, Campinho, Lorena, SP, 12602-810, Brazil
| | - George J M Rocha
- Department of Biotechnology, Engineering College of Lorena, University of São Paulo (USP), Estrada Municipal Do Campinho, s/n, Campinho, Lorena, SP, 12602-810, Brazil. .,Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Rua Giuseppe Máximo Scolfaro 10.000, Campinas, SP, 13083-100, Brazil.
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13
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Balasundaram G, Banu R, Varjani S, Kazmi AA, Tyagi VK. Recalcitrant compounds formation, their toxicity, and mitigation: Key issues in biomass pretreatment and anaerobic digestion. CHEMOSPHERE 2022; 291:132930. [PMID: 34800498 DOI: 10.1016/j.chemosphere.2021.132930] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/04/2021] [Accepted: 11/14/2021] [Indexed: 06/13/2023]
Abstract
Increasing energy demands and environmental issues have stressed the importance of sustainable methods of energy production. Anaerobic digestion (AD) of the biodegradable waste, i.e., agricultural residues, organic fraction of municipal solid waste (OFMSW), sewage sludge, etc., results in the production of biogas, which is a sustainable and cost feasible technique that reduces the dependence on fossil fuels and also overcomes the problems associated with biomass waste management. To solubilize the organic matter and enhance the susceptibility of hardly biodegradable fraction (i.e., lignocellulosic) for hydrolysis and increase methane production, several pretreatments, including physical, chemical, biological, and hybrid methods have been studied. However, these pretreatment methods under specific operating conditions result in the formation of recalcitrant compounds, such as sugars (xylose, Xylo-oligomers), organic acids (acetic, formic, levulinic acids), and lignin derivatives (poly and mono-phenolic compounds), causing significant inhibitory effects on anaerobic digestion. During the scaling up of these techniques from laboratory to industrial level, the focus on managing inhibitory compounds formed during pretreatment is envisaged to increase because of the need to use recalcitrant feedstocks in anaerobic digestion to increase biogas productivity. Therefore, it is crucial to understand the production mechanism of inhibitory compounds during pretreatment and work out the possible detoxification methods to improve anaerobic digestion. This paper critically reviews the earlier works based on the formation of recalcitrant compounds during feedstocks pretreatment under variable conditions, and their detrimental effects on process performance. The technologies to mitigate recalcitrant toxicity are also comprehensively discussed.
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Affiliation(s)
- Gowtham Balasundaram
- Environmental BioTechnology Group (EBiTG), Department of Civil Engineering, Indian Institute of Technology, Roorkee, Roorkee, 247667, India
| | - Rajesh Banu
- Department of Life Sciences, Central University of Tamil Nadu, Thiruvarur 610005, Tamil Nadu, India
| | - Sunita Varjani
- Gujarat Pollution Control Board, Gandhinagar, 382 010, Gujarat, India
| | - A A Kazmi
- Environmental BioTechnology Group (EBiTG), Department of Civil Engineering, Indian Institute of Technology, Roorkee, Roorkee, 247667, India
| | - Vinay Kumar Tyagi
- Environmental BioTechnology Group (EBiTG), Department of Civil Engineering, Indian Institute of Technology, Roorkee, Roorkee, 247667, India.
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Physiological comparisons among Spathaspora passalidarum, Spathaspora arborariae, and Scheffersomyces stipitis reveal the bottlenecks for their use in the production of second-generation ethanol. Braz J Microbiol 2022; 53:977-990. [PMID: 35174461 PMCID: PMC9151973 DOI: 10.1007/s42770-022-00693-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 12/21/2021] [Indexed: 02/01/2023] Open
Abstract
The microbial conversion of pentoses to ethanol is one of the major drawbacks that limits the complete use of lignocellulosic sugars. In this study, we compared the yeast species Spathaspora arborariae, Spathaspora passalidarum, and Sheffersomyces stipitis regarding their potential use for xylose fermentation. Herein, we evaluated the effects of xylose concentration, presence of glucose, and temperature on ethanol production. The inhibitory effects of furfural, hydroxymethylfurfural (HMF), acetic acid, and ethanol were also determined. The highest ethanol yield (0.44 g/g) and productivity (1.02 g/L.h) were obtained using Sp. passalidarum grown in 100 g/L xylose at 32 °C. The rate of xylose consumption was reduced in the presence of glucose for the species tested. Hydroxymethylfurfural did not inhibit the growth of yeasts, whereas furfural extended their lag phase. Acetic acid inhibited the growth and fermentation of all yeasts. Furthermore, we showed that these xylose-fermenting yeasts do not produce ethanol concentrations greater than 4% (v/v), probably due to the inhibitory effects of ethanol on yeast physiology. Our data confirm that among the studied yeasts, Sp. passalidarum is the most promising for xylose fermentation, and the low tolerance to ethanol is an important aspect to be improved to increase its performance for second-generation (2G) ethanol production. Our molecular data showed that this yeast failed to induce the expression of some classical genes involved in ethanol tolerance. These findings suggest that Sp. passalidarum may have not activated a proper response to the stress, impacting its ability to overcome the negative effects of ethanol on the cells.
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Liu T, Zuo J, Shen Z, Zhou Y. Inhibition of biological acidification and mechanism of crotonaldehyde removal with glucose cometabolism. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 303:114090. [PMID: 34810021 DOI: 10.1016/j.jenvman.2021.114090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 11/06/2021] [Accepted: 11/08/2021] [Indexed: 06/13/2023]
Abstract
Biological acidification is an effective method in the treatment or pretreatment of industrial wastewater. Crotonaldehyde is a typical characteristic organic pollutant in petrochemical wastewater, but its effect on biological acidification is unclear. To investigate the inhibitory characteristic of crotonaldehyde on biological acidification and the mechanism of crotonaldehyde removal, variations in volatile fatty acid (VFA) yields, enzyme activities, biodegradation products, and microbial community structures were investigated by batch experiments in the presence of crotonaldehyde. The results showed that crotonaldehyde caused a 50% effect concentration (EC50) on the specific acidogenic activity (SAA) of 204.17 mg/L before 24 h, and then, the inhibitory effect was removed after 48 h as the dosage of crotonaldehyde was less than 1000 mg/L. Accordingly, crotonaldehyde was completely reduced to crotonyl alcohol by nicotinamide adenine dinucleotide (NADH) or oxidized to (E)-crotonic acid by aldehyde dehydrogenase (DHO) after 48 h. Next, 1-buanol and n-butyric acid were further metabolites, while the n-hexanoic acid detected with high-concentration crotonaldehyde might be due to the ORB pathway with 1-buanol as an electron donor. The dominant bacterial communities were Clostridium_sensu_stricto_1, Clostridium_sensu_stricto_11, Clostridium_sensu_stricto_12, which were related to the biodegradation process of crotonaldehyde. The findings of this research could provide a theoretical underpinning for developing the biological technologies to pretreat crotonaldehyde wastewater.
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Affiliation(s)
- Tao Liu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China; Research Center of Environmental Pollution Control Engineering Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China; School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Jiane Zuo
- School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Zhiqiang Shen
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China; Research Center of Environmental Pollution Control Engineering Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China.
| | - Yuexi Zhou
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China; Research Center of Environmental Pollution Control Engineering Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China.
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Branduardi P, Barroso L, Dato L, Louis EJ, Porro D. Molecular Tools for Leveraging the Potential of the Acid-Tolerant Yeast Zygosaccharomyces bailii as Cell Factory. Methods Mol Biol 2022; 2513:179-204. [PMID: 35781206 DOI: 10.1007/978-1-0716-2399-2_11] [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] [Indexed: 06/15/2023]
Abstract
Microorganisms offer a tremendous potential as cell factories, and they are indeed been used by humans since the previous centuries for biotransformations. Among them, yeasts combine the advantage of a unicellular state with a eukaryotic organization. Moreover, in the era of biorefineries, their biodiversity can offer solutions to specific process constraints. Zygosaccharomyces bailii, an ascomycete budding yeast, is widely known for its peculiar tolerance to different stresses, among which are organic acids. Moreover, the recent reclassification of the species, including diverse hybrids, is further expanding both fundamental and applied interests. It is therefore reasonable that despite the possibility to apply with this yeast some of the molecular tools and protocols routinely used to manipulate Saccharomyces cerevisiae, adjustments and optimizations are necessary. Here we describe in detail the methods for determining chromosome number, size, and aneuploidy, transformation, classical target gene disruption or gene integration, and designing of episomal expression plasmids helpful for engineering the yeast Z. bailii .
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Affiliation(s)
- Paola Branduardi
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy.
| | - Liliane Barroso
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
- Department of Genetics & Genome Biology, University of Leicester, Leicester, UK
| | - Laura Dato
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Edward J Louis
- Department of Genetics & Genome Biology, University of Leicester, Leicester, UK
| | - Danilo Porro
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
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17
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Zhang N, Shang Y, Wang F, Wang D, Hong J. Influence of prefoldin subunit 4 on the tolerance of Kluyveromyces marxianus to lignocellulosic biomass-derived inhibitors. Microb Cell Fact 2021; 20:224. [PMID: 34906148 PMCID: PMC8672639 DOI: 10.1186/s12934-021-01715-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 12/02/2021] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Kluyveromyces marxianus is a potentially excellent host for microbial cell factories using lignocellulosic biomass, due to its thermotolerance, high growth rate, and wide substrate spectrum. However, its tolerance to inhibitors derived from lignocellulosic biomass pretreatment needs to be improved. The prefoldin complex assists the folding of cytoskeleton which relates to the stress tolerance, moreover, several subunits of prefoldin have been verified to be involved in gene expression regulation. With the presence of inhibitors, the expression of a gene coding the subunit 4 of prefoldin (KmPFD4), a possible transcription factor, was significantly changed. Therefore, KmPFD4 was selected to evaluate its functions in inhibitors tolerance. RESULTS In this study, the disruption of the prefoldin subunit 4 gene (KmPFD4) led to increased concentration of intracellular reactive oxygen species (ROS) and disturbed the assembly of actin and tubulin in the presence of inhibitors, resulting in reduced inhibitor tolerance. Nuclear localization of KmPFD4 indicated that it could regulate gene expression. Transcriptomic analysis showed that upregulated gene expression related to ROS elimination, ATP production, and NAD+ synthesis, which is a response to the presence of inhibitors, disappeared in KmPFD4-disrupted cells. Thus, KmPFD4 impacts inhibitor tolerance by maintaining integration of the cytoskeleton and directly or indirectly affecting the expression of genes in response to inhibitors. Finally, overexpression of KmPFD4 enhanced ethanol fermentation with a 46.27% improvement in productivity in presence of the inhibitors. CONCLUSION This study demonstrated that KmPFD4 plays a positive role in the inhibitor tolerance and can be applied for the development of inhibitor-tolerant platform strains.
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Affiliation(s)
- Nini Zhang
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, People's Republic of China
| | - Yingying Shang
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, People's Republic of China
| | - Feier Wang
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, People's Republic of China
| | - Dongmei Wang
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, People's Republic of China.
- Biomedical Sciences and Health Laboratory of Anhui Province, University of Science & Technology of China, Hefei, 230027, China.
| | - Jiong Hong
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, People's Republic of China.
- Hefei National Laboratory for Physical Science at the Microscale, Hefei, Anhui, 230026, People's Republic of China.
- Biomedical Sciences and Health Laboratory of Anhui Province, University of Science & Technology of China, Hefei, 230027, China.
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18
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Adaptation of Saccharomyces cerevisiae in a concentrated spent sulphite liquor waste stream for increased inhibitor resistance. Appl Microbiol Biotechnol 2021; 106:455-468. [PMID: 34870737 DOI: 10.1007/s00253-021-11710-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 11/21/2021] [Accepted: 11/24/2021] [Indexed: 10/19/2022]
Abstract
The fermentation of spent sulphite liquor (SSL) from the pulping of hardwoods is limited by the combination of xylose, the primary fermentable sugar and high concentrations of microbial inhibitors that decrease the yeast fermentation ability. The inhibitor resistance phenotypes of xylose-capable Saccharomyces cerevisiae strains were therefore enhanced by combining rational engineering for multi-inhibitor tolerance, with adaptation in concentrated hardwood SSL as selective pressure. The adapted strains were assessed in fermentations with 60-80% v/v concentrated SSL under industrially relevant fermentation conditions. During adaptation, strains produced ethanol concentrations between 11.0 and 15.4 g/L in the range of that reported in literature. The adapted TFA40 and TP50 strains displayed enhanced inhibitor resistance phenotypes and were able to ferment xylose-rich SSL at pH below 5, exhibiting improved ethanol yields relative to the reference strain. Using yeast extract and peptone as nitrogen source in concentrated SSL fermentations further improved ethanol yields. However, strains exhibited a trade-off between resistance and ethanol productivity, indicating a carbon/energy cost for the expression of this inhibitor tolerance phenotype. KEY POINTS : • Achieved fermentation of xylose-rich hardwood spent sulphite liquor at pH below 5.0 • Adaptation of xylose-capable S. cerevisiae in concentrated spent sulphite liquor • Adapted strains exhibited enhanced inhibitor resistance phenotypes.
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Hoang AT, Nizetic S, Ong HC, Chong CT, Atabani AE, Pham VV. Acid-based lignocellulosic biomass biorefinery for bioenergy production: Advantages, application constraints, and perspectives. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 296:113194. [PMID: 34243094 DOI: 10.1016/j.jenvman.2021.113194] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 06/14/2021] [Accepted: 06/29/2021] [Indexed: 06/13/2023]
Abstract
The production of chemicals and fuels from renewable biomass with the primary aim of reducing carbon footprints has recently become one of the central points of interest. The use of lignocellulosic biomass for energy production is believed to meet the main criteria of maximizing the available global energy source and minimizing pollutant emissions. However, before usage in bioenergy production, lignocellulosic biomass needs to undergo several processes, among which biomass pretreatment plays an important role in the yield, productivity, and quality of the products. Acid-based pretreatment, one of the existing methods applied for lignocellulosic biomass pretreatment, has several advantages, such as short operating time and high efficiency. A thorough analysis of the characteristics of acid-based biomass pretreatment is presented in this review. The environmental concerns and future challenges involved in using acid pretreatment methods are discussed in detail to achieve clean and sustainable bioenergy production. The application of acid to biomass pretreatment is considered an effective process for biorefineries that aim to optimize the production of desired products while minimizing the by-products.
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Affiliation(s)
- Anh Tuan Hoang
- Institute of Engineering, Ho Chi Minh City University of Technology (HUTECH), Ho Chi Minh City, Viet Nam.
| | - Sandro Nizetic
- University of Split, FESB, Rudjera Boskovica 32, 21000, Split, Croatia
| | - Hwai Chyuan Ong
- Centre for Green Technology, Faculty of Engineering and IT, University of Technology Sydney, NSW, 2007, Australia.
| | - Cheng Tung Chong
- China-UK Low Carbon College, Shanghai Jiao Tong University, Lingang, Shanghai, 201306, China
| | - A E Atabani
- Alternative Fuels Research Laboratroy (AFRL), Energy Division, Department of Mechanical Engineering, Faculty of Engineering, Erciyes University, 38039, Kayseri, Turkey
| | - Van Viet Pham
- Institute of Maritime, Ho Chi Minh City University of Transport, Ho Chi Minh City, Viet Nam.
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Vancov T, Palmer J, Keen B. Pilot scale demonstration of a two-stage pretreatment and bioethanol fermentation process for cotton gin trash. BIORESOURCE TECHNOLOGY 2021; 335:125224. [PMID: 33984554 DOI: 10.1016/j.biortech.2021.125224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/21/2021] [Accepted: 04/23/2021] [Indexed: 06/12/2023]
Abstract
A two-stage dilute acid and steam explosion (SE) pretreatment process was developed and evaluated at pilot scale for ethanol production from cotton gin trash (CGT). Optimal conditions for CGT processing were defined as 1:6 solids to liquids ratio with 9% H2SO4 wt. on solids at 180 °C for 15 min. during stage 1 with ensuing pressed fibres successively exposed to SE at 200 °C for 5 min during stage 2. SE fibres were highly acquiescent to enzyme hydrolysis (76%) in the presence of PEG 6000, yielding 381 g glucose kg-1 fibre. Simultaneous saccharification and fermentation (SSF) trials validated the selected process option and additional fed-batch SSFs confirmed titres above the minimum 4% ww-1 benchmark for economically viable distillation. The practicality of converting CGT to ethanol was demonstrated at pilot scale with titres above 4% ww-1 and a conversion efficiency of 60% t-1 dry GCT.
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Affiliation(s)
- T Vancov
- NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, NSW, Australia.
| | - J Palmer
- NSW Department of Primary Industries, Wollongbar Primary Industries Institute, NSW, Australia
| | - B Keen
- NSW Department of Primary Industries, Wollongbar Primary Industries Institute, NSW, Australia
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21
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Liu Z, Radi M, Mohamed ETT, Feist AM, Dragone G, Mussatto SI. Adaptive laboratory evolution of Rhodosporidium toruloides to inhibitors derived from lignocellulosic biomass and genetic variations behind evolution. BIORESOURCE TECHNOLOGY 2021; 333:125171. [PMID: 33894448 DOI: 10.1016/j.biortech.2021.125171] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/07/2021] [Accepted: 04/08/2021] [Indexed: 06/12/2023]
Abstract
Using lignocellulosic biomass hydrolysate for the production of microbial lipids and carotenoids is still a challenge due to the poor tolerance of oleaginous yeasts to the inhibitors generated during biomass pretreatment. In this study, a strategy of adaptive laboratory evolution in hydrolysate-based medium was developed to improve the tolerance of Rhodosporidium toruloides to inhibitors present in biomass hydrolysate. The evolved strains presented better performance to grow in hydrolysate medium, with a significant reduction in their lag phases, and improved ability to accumulate lipids and produce carotenoids when compared to the wild-type starting strain. In the best cases, the lag phase was reduced by 72 h and resulted in lipid accumulation of 27.89 ± 0.80% (dry cell weight) and carotenoid production of 14.09 ± 0.12 mg/g (dry cell weight). Whole genome sequencing analysis indicated that the wild-type strain naturally contained tolerance-related genes, which provided a background that allowed the strain to evolve in biomass-derived inhibitors.
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Affiliation(s)
- Zhijia Liu
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, 2800 Kongens Lyngby, Denmark
| | - Mohammad Radi
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, 2800 Kongens Lyngby, Denmark
| | - Elsayed T T Mohamed
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, 2800 Kongens Lyngby, Denmark
| | - Adam M Feist
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, 2800 Kongens Lyngby, Denmark; Department of Bioengineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0412, USA
| | - Giuliano Dragone
- Department of Biotechnology and Biomedicine, Technical University of Denmark, SøltoftsPlads, Building 223, 2800 Kongens Lyngby, Denmark
| | - Solange I Mussatto
- Department of Biotechnology and Biomedicine, Technical University of Denmark, SøltoftsPlads, Building 223, 2800 Kongens Lyngby, Denmark.
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22
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Cao W, Zhao W, Yang B, Wang X, Shen Y, Wei T, Qin W, Li Z, Bao X. Proteomic analysis revealed the roles of YRR1 deletion in enhancing the vanillin resistance of Saccharomyces cerevisiae. Microb Cell Fact 2021; 20:142. [PMID: 34301255 PMCID: PMC8305865 DOI: 10.1186/s12934-021-01633-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 07/15/2021] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Vanillin is one of the important phenolic inhibitors in Saccharomyces cerevisiae for bioconversion of lignocellulosic materials and has been reported to inhibit the translation process in cells. In our previous studies, it was confirmed that the deletion of the transcription factor gene YRR1 enhanced vanillin resistance by promoting some translation-related processes at the transcription level. In this work, we investigated the effects of proteomic changes upon induction of vanillin stress and deletion of YRR1 to provide unique perspectives from a transcriptome analysis for comprehending the mechanisms of YRR1 deletion in the protective response of yeast to vanillin. RESULTS In wild-type cells, vanillin reduced two dozens of ribosomal proteins contents while upregulated proteins involved in glycolysis, oxidative phosphorylation, and the pentose phosphate pathway in cells. The ratios of NADPH/NADP+ and NADH/NAD+ were increased when cells responded to vanillin stress. The differentially expressed proteins perturbed by YRR1 deletion were much more abundant than and showed no overlaps with transcriptome changes, indicating that Yrr1 affects the synthesis of certain proteins. Forty-eight of 112 upregulated proteins were involved in the stress response, translational and transcriptional regulation. YRR1 deletion increased the expression of HAA1-encoding transcriptional activator, TMA17-encoding proteasome assembly chaperone and MBF1-encoding coactivator at the protein level, as confirmed by ELISA. Cultivation data showed that the overexpression of HAA1 and TMA17 enhanced resistance to vanillin in S. cerevisiae. CONCLUSIONS Cells conserve energy by decreasing the content of ribosomal proteins, producing more energy and NAD(P)H for survival in response to vanillin stress. Yrr1 improved vanillin resistance by increasing the protein quantities of Haa1, Tma17 and Mbf1. These results showed the response of S. cerevisiae to vanillin and how YRR1 deletion increases vanillin resistance at the protein level. These findings may advance our knowledge of how YRR1 deletion protects yeast from vanillin stress and offer novel targets for genetic engineering of designing inhibitor-resistant ethanologenic yeast strains.
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Affiliation(s)
- Wenyan Cao
- State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Key Laboratory of Shandong Microbial Engineering, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan, 250353, China
| | - Weiquan Zhao
- State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Key Laboratory of Shandong Microbial Engineering, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan, 250353, China
| | - Bolun Yang
- State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Key Laboratory of Shandong Microbial Engineering, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan, 250353, China
| | - Xinning Wang
- State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Key Laboratory of Shandong Microbial Engineering, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan, 250353, China.
| | - Yu Shen
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Binhai Road 72, Qingdao, 266237, China
| | - Tiandi Wei
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Binhai Road 72, Qingdao, 266237, China
| | - Wensheng Qin
- Department of Biology, Lakehead University, 955 Oliver Rd, Thunder Bay, ON, P7B 5E1, Canada
| | - Zailu Li
- State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Key Laboratory of Shandong Microbial Engineering, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan, 250353, China
| | - Xiaoming Bao
- State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Key Laboratory of Shandong Microbial Engineering, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan, 250353, China
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Adebami GE, Kuila A, Ajunwa OM, Fasiku SA, Asemoloye MD. Genetics and metabolic engineering of yeast strains for efficient ethanol production. J FOOD PROCESS ENG 2021. [DOI: 10.1111/jfpe.13798] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
| | - Arindam Kuila
- Department of Bioscience and Biotechnology Banasthali University Vanasthali India
| | - Obinna M. Ajunwa
- Department of Microbiology Modibbo Adama University of Technology Yola Nigeria
| | - Samuel A. Fasiku
- Department of Biological Sciences Ajayi Crowther University Oyo Nigeria
| | - Michael D. Asemoloye
- Department of Pharmaceutical Science and Technology Tianjin University Tianjin China
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Stress modulation as a means to improve yeasts for lignocellulose bioconversion. Appl Microbiol Biotechnol 2021; 105:4899-4918. [PMID: 34097119 DOI: 10.1007/s00253-021-11383-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 05/20/2021] [Accepted: 05/28/2021] [Indexed: 12/15/2022]
Abstract
The second-generation (2G) fermentation environment for lignocellulose conversion presents unique challenges to the fermentative organism that do not necessarily exist in other industrial fermentations. While extreme osmotic, heat, and nutrient starvation stresses are observed in sugar- and starch-based fermentation environments, additional pre-treatment-derived inhibitor stress, potentially exacerbated by stresses such as pH and product tolerance, exist in the 2G environment. Furthermore, in a consolidated bioprocessing (CBP) context, the organism is also challenged to secrete enzymes that may themselves lead to unfolded protein response and other stresses. This review will discuss responses of the yeast Saccharomyces cerevisiae to 2G-specific stresses and stress modulation strategies that can be followed to improve yeasts for this application. We also explore published -omics data and discuss relevant rational engineering, reverse engineering, and adaptation strategies, with the view of identifying genes or alleles that will make positive contributions to the overall robustness of 2G industrial strains. KEYPOINTS: • Stress tolerance is a key driver to successful application of yeast strains in biorefineries. • A wealth of data regarding stress responses has been gained through omics studies. • Integration of this knowledge could inform engineering of fit for purpose strains.
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Liu ZL. Reasons for 2-furaldehyde and 5-hydroxymethyl-2-furaldehyde resistance in Saccharomyces cerevisiae: current state of knowledge and perspectives for further improvements. Appl Microbiol Biotechnol 2021; 105:2991-3007. [PMID: 33830300 DOI: 10.1007/s00253-021-11256-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 03/16/2021] [Accepted: 03/23/2021] [Indexed: 11/25/2022]
Abstract
Common toxic compounds 2-furaldehyde (furfural) and 5-hydroxymethyl-2-furaldehyde (HMF) are formed from dehydration of pentose and hexose, respectively, during decomposition of lignocellulosic biomass polymers. Furfural and HMF represent a major class of aldehyde toxic chemicals that inhibit microbial growth and interfere with subsequent fermentation for production of renewable fuels and chemicals. Understanding mechanisms of yeast tolerance aids development of tolerant strains as the most economic means to overcome the toxicity. This review updates current knowledge on yeast resistance to these toxic chemicals obtained from rapid advances in the past few years. Findings are largely exemplified by an adapted strain NRRL Y-50049 compared with its progenitor, the industrial yeast Saccharomyces cerevisiae type strain NRRL Y-12632. Newly characterized molecular phenotypes distinguished acquired resistant components of Y-50049 from innate stress response of its progenitor Y-12632. These findings also raised important questions on how to address more deeply ingrained changes in addition to local renovations for yeast adaptation. An early review on understandings of yeast tolerance to these inhibitory compounds is available and its contents omitted here to avoid redundancy. Controversial and confusing issues on identification of yeast resistance to furfural and HMF are further clarified aiming improved future research. Propositions and perspectives on research understanding molecular mechanisms of yeast resistance and future improvements are also presented. KEY POINTS: • Distinguished adapted resistance from innate stress response in yeast. • Defined pathway-based molecular phenotypes of yeast resistance. • Proposed genomic insight and perspectives on yeast resistance and adaptation.
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Affiliation(s)
- Z Lewis Liu
- National Center for Agricultural Utilization Research, Bioenergy Research Unit, USDA Agricultural Research Service, 1815 N. University Street, Peoria, IL, 61604, USA.
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26
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Analysis of the response of the cell membrane of Saccharomyces cerevisiae during the detoxification of common lignocellulosic inhibitors. Sci Rep 2021; 11:6853. [PMID: 33767301 PMCID: PMC7994549 DOI: 10.1038/s41598-021-86135-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 03/11/2021] [Indexed: 01/31/2023] Open
Abstract
Gaining an in-depth understanding of the response of Saccharomyces cerevisiae to the different inhibitors generated during the pretreatment of lignocellulosic material is driving the development of new strains with higher inhibitor tolerances. The objective of this study is to assess, using flow cytometry, how three common inhibitors (vanillin, furfural, and acetic acid) affect the membrane potential, the membrane permeability and the concentration of reactive oxygen species (ROS) during the different fermentations. The membrane potential decreased during the detoxification phase and reflected on the different mechanisms of the toxicity of the inhibitors. While vanillin and furfural caused a metabolic inhibition and a gradual depolarization, acetic acid toxicity was related to fast acidification of the cytosol, causing an immediate depolarization. In the absence of acetic acid, ethanol increased membrane permeability, indicating a possible acquired tolerance to ethanol due to an adaptive response to acetic acid. The intracellular ROS concentration also increased in the presence of the inhibitors, indicating oxidative stress. Measuring these features with flow cytometry allows a real-time assessment of the stress of a cell culture, which can be used in the development of new yeast strains and to design new propagation strategies to pre-adapt the cell cultures to the inhibitors.
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27
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Jayakody LN, Jin YS. In-depth understanding of molecular mechanisms of aldehyde toxicity to engineer robust Saccharomyces cerevisiae. Appl Microbiol Biotechnol 2021; 105:2675-2692. [PMID: 33743026 DOI: 10.1007/s00253-021-11213-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 02/17/2021] [Accepted: 02/28/2021] [Indexed: 11/25/2022]
Abstract
Aldehydes are ubiquitous electrophilic compounds that ferment microorganisms including Saccharomyces cerevisiae encounter during the fermentation processes to produce food, fuels, chemicals, and pharmaceuticals. Aldehydes pose severe toxicity to the growth and metabolism of the S. cerevisiae through a variety of toxic molecular mechanisms, predominantly via damaging macromolecules and hampering the production of targeted compounds. Compounds with aldehyde functional groups are far more toxic to S. cerevisiae than all other functional classes, and toxic potency depends on physicochemical characteristics of aldehydes. The yeast synthetic biology community established a design-build-test-learn framework to develop S. cerevisiae cell factories to valorize the sustainable and renewable biomass, including the lignin-derived substrates. However, thermochemically pretreated biomass-derived substrate streams contain diverse aldehydes (e.g., glycolaldehyde and furfural), and biological conversions routes of lignocellulosic compounds consist of toxic aldehyde intermediates (e.g., formaldehyde and methylglyoxal), and some of the high-value targeted products have aldehyde functional group (e.g., vanillin and benzaldehyde). Numerous studies comprehensively characterized both single and additive effects of aldehyde toxicity via systems biology investigations, and novel molecular approaches have been discovered to overcome the aldehyde toxicity. Based on those novel approaches, researchers successfully developed synthetic yeast cell factories to convert lignocellulosic substrates to valuable products, including aldehyde compounds. In this mini-review, we highlight the salient relationship of physicochemical characteristics and molecular toxicity of aldehydes, the molecular detoxification and macromolecules protection mechanisms of aldehydes, and the advances of engineering robust S. cerevisiae against complex mixtures of aldehyde inhibitors. KEY POINTS: • We reviewed structure-activity relationships of aldehyde toxicity on S. cerevisiae. • Two-tier protection mechanisms to alleviate aldehyde toxicity are presented. • We highlighted the strategies to overcome the synergistic toxicity of aldehydes.
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Affiliation(s)
- Lahiru N Jayakody
- School of Biological Sciences, Southern Illinois University Carbondale, Carbondale, IL, USA.
- Fermentation Science Institute, Southern Illinois University Carbondale, Carbondale, IL, USA.
| | - Yong-Su Jin
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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28
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Kumari S, Kumar M, Gaur NA, Prasad R. Multiple roles of ABC transporters in yeast. Fungal Genet Biol 2021; 150:103550. [PMID: 33675986 DOI: 10.1016/j.fgb.2021.103550] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 01/29/2021] [Accepted: 02/25/2021] [Indexed: 12/20/2022]
Abstract
The ATP binding cassette (ABC) transporters, first discovered as high-affinity nutrient importers in bacteria, rose to prominence when their ability to confer multidrug resistance (MDR) to cancer cells was realized. The most characterized human permeability glycoprotein (P-gp) is a dominant exporter of anti-cancer drugs and its overexpression is directly linked to MDR. The overexpression of drug efflux pumps belonging to the ABC superfamily is also a frequent cause of resistance to antifungals. Fungi has a battery of ABC proteins, but in variable numbers and at different subcellular locations. These proteins perform many critical functions, from serving as gatekeepers for xenobiotic cleansing to translocating various structurally unrelated cargoes, including lipids, fatty acids, ions, peptides, sterols, metabolites and toxins. Their emerging additional roles in cellular physiology and virulence call for attention to analyze and re-examine their divergent functions in yeast. In brief, this review traces the history of ABC transporters in yeast and discusses their typical physiological functions that go beyond their well-known role as antifungal drug efflux pumps.
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Affiliation(s)
- Sonam Kumari
- Yeast Biofuel Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Mohit Kumar
- Yeast Biofuel Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India; Amity Institute of Integrative Science and Health, Amity Institute of Biotechnology, Amity University Gurgaon, 122413 Haryana, India
| | - Naseem A Gaur
- Yeast Biofuel Group, International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India.
| | - Rajendra Prasad
- Amity Institute of Integrative Science and Health, Amity Institute of Biotechnology, Amity University Gurgaon, 122413 Haryana, India.
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29
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Kłosowski G, Mikulski D. Impact of Lignocellulose Pretreatment By-Products on S. cerevisiae Strain Ethanol Red Metabolism during Aerobic and An-aerobic Growth. Molecules 2021; 26:molecules26040806. [PMID: 33557207 PMCID: PMC7913964 DOI: 10.3390/molecules26040806] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 01/31/2021] [Accepted: 02/01/2021] [Indexed: 11/16/2022] Open
Abstract
Understanding the specific response of yeast cells to environmental stress factors is the starting point for selecting the conditions of adaptive culture in order to obtain a yeast line with increased resistance to a given stress factor. The aim of the study was to evaluate the specific cellular response of Saccharomyces cerevisiae strain Ethanol Red to stress caused by toxic by-products generated during the pretreatment of lignocellulose, such as levulinic acid, 5-hydroxymethylfurfural, furfural, ferulic acid, syringaldehyde and vanillin. The presence of 5-hydroxymethylfurfural at the highest analyzed concentration (5704.8 ± 249.3 mg/L) under aerobic conditions induced the overproduction of ergosterol and trehalose. On the other hand, under anaerobic conditions (during the alcoholic fermentation), a decrease in the biosynthesis of these environmental stress indicators was observed. The tested yeast strain was able to completely metabolize 5-hydroxymethylfurfural, furfural, syringaldehyde and vanillin, both under aerobic and anaerobic conditions. Yeast cells reacted to the presence of furan aldehydes by overproducing Hsp60 involved in the control of intracellular protein folding. The results may be helpful in optimizing the process parameters of second-generation ethanol production, in order to reduce the formation and toxic effects of fermentation inhibitors.
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30
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Paes BG, Steindorff AS, Formighieri EF, Pereira IS, Almeida JRM. Physiological characterization and transcriptome analysis of Pichia pastoris reveals its response to lignocellulose-derived inhibitors. AMB Express 2021; 11:2. [PMID: 33389238 PMCID: PMC7779389 DOI: 10.1186/s13568-020-01170-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 12/16/2020] [Indexed: 12/11/2022] Open
Abstract
The negative effects of lignocellulose-derived inhibitors such as acetic acid and furaldehydes on microbial metabolism constitute a significant drawback to the usage of biomass feedstocks for the production of fuels and chemicals. The yeast Pichia pastoris has shown a great biotechnological potential for producing heterologous proteins and renewable chemicals. Despite its relevance, the performance of P. pastoris in presence of lignocellulose-derived inhibitors remains unclear. In this work, our results show for the first time the dose-dependent response of P. pastoris to acetic acid, furaldehydes (HMF and furfural), and sugarcane biomass hydrolysate, both at physiological and transcriptional levels. The yeast was able to grow in synthetic media with up to 6 g.L-1 acetic acid, 1.75 g.L-1 furaldehydes or hydrolysate diluted to 10% (v/v). However, its metabolism was completely hindered in presence of hydrolysate diluted to 30% (v/v). Additionally, the yeast was capable to co-consume acetic acid and glucose. At the transcriptional level, P. pastoris response to lignocellulose-derived inhibitors relays on the up-regulation of genes related to transmembrane transport, oxidoreductase activities, RNA processing, and the repression of pathways related to biosynthetic processes and central carbon metabolism. These results demonstrate a polygenetic response that involves detoxification activities, and maintenance of energy and cellular homeostasis. In this context, ALD4, OYE3, QOR2, NTL100, YCT1, and PPR1 were identified as target genes to improve P. pastoris tolerance. Altogether, this work provides valuable insights into the P. pastoris stress tolerance, which can be useful to expand its use in different bioprocesses.
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Affiliation(s)
- Barbara G Paes
- Laboratory of Genetics and Biotechnology, Embrapa Agroenergia, Parque Estação Biológica, PqEB - W3 Norte Final s/no, Brasília, DF, 70.770-901, Brazil
- Graduate Program of Molecular Biology, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, Brazil
| | - Andrei Stecca Steindorff
- Laboratory of Genetics and Biotechnology, Embrapa Agroenergia, Parque Estação Biológica, PqEB - W3 Norte Final s/no, Brasília, DF, 70.770-901, Brazil
| | - Eduardo F Formighieri
- Laboratory of Genetics and Biotechnology, Embrapa Agroenergia, Parque Estação Biológica, PqEB - W3 Norte Final s/no, Brasília, DF, 70.770-901, Brazil
| | - Ildinete Silva Pereira
- Laboratory of Genetics and Biotechnology, Embrapa Agroenergia, Parque Estação Biológica, PqEB - W3 Norte Final s/no, Brasília, DF, 70.770-901, Brazil
- Graduate Program of Molecular Biology, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, Brazil
| | - João Ricardo M Almeida
- Laboratory of Genetics and Biotechnology, Embrapa Agroenergia, Parque Estação Biológica, PqEB - W3 Norte Final s/no, Brasília, DF, 70.770-901, Brazil.
- Graduate Program of Microbial Biology, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, Brazil.
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Sehnem NT, Machado ÂS, Matte CR, Morais MADE, Ayub MAZ. Second-generation ethanol production by Wickerhamomyces anomalus strain adapted to furfural, 5-hydroxymethylfurfural (HMF), and high osmotic pressure. AN ACAD BRAS CIENC 2020; 92:e20181030. [PMID: 33084752 DOI: 10.1590/0001-3765202020181030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 04/08/2019] [Indexed: 11/22/2022] Open
Abstract
The aims of this work were to improve cell tolerance towards high concentrations of furfural and 5-hydroxymethylfurfural (HMF) of an osmotolerant strain of Wickerhamomyces anomalus by means of evolutionary engineering, and to determine its ethanol production under stress conditions. Cells were grown in the presence of furfural, HMF, either isolated or in combination, and under high osmotic pressure conditions. The most toxic condition for the parental strain was the combination of both furans, under which it was unable to grow and to produce ethanol. However, the tolerant adapted strain achieved a yield of ethanol of 0.43 g g-1glucose in the presence of furfural and HMF, showing an alcohol dehydrogenase activity of 0.68 mU mg protein-1. For this strain, osmotic pressure, did not affect its growth rate. These results suggest that W. anomalus WA-HF5.5strain shows potential to be used in second-generation ethanol production systems.
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Affiliation(s)
- Nicole T Sehnem
- Universidade Federal do Rio Grande do Sul, Departamento de Tecnologia de Alimentos, Av. Bento Gonçalves, 9500, Campus do Vale, 91501-970 Porto Alegre, RS, Brazil
| | - Ângela S Machado
- Universidade Federal do Rio Grande do Sul, Departamento de Tecnologia de Alimentos, Av. Bento Gonçalves, 9500, Campus do Vale, 91501-970 Porto Alegre, RS, Brazil
| | - Carla R Matte
- Universidade Federal do Rio Grande do Sul, Departamento de Tecnologia de Alimentos, Av. Bento Gonçalves, 9500, Campus do Vale, 91501-970 Porto Alegre, RS, Brazil
| | - Marcos Antonio DE Morais
- Universidade Federal de Pernambuco, Departamento de Genética, Av. Moraes Rego, 1235, Cidade Universitária, 50670901 Recife, PE, Brazil
| | - Marco AntÔnio Z Ayub
- Universidade Federal do Rio Grande do Sul, Departamento de Tecnologia de Alimentos, Av. Bento Gonçalves, 9500, Campus do Vale, 91501-970 Porto Alegre, RS, Brazil
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32
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Origin, Impact and Control of Lignocellulosic Inhibitors in Bioethanol Production—A Review. ENERGIES 2020. [DOI: 10.3390/en13184751] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Bioethanol production from lignocellulosic biomass is still struggling with many obstacles. One of them is lignocellulosic inhibitors. The aim of this review is to discuss the most known inhibitors. Additionally, the review addresses different detoxification methods to degrade or to remove inhibitors from lignocellulosic hydrolysates. Inhibitors are formed during the pretreatment of biomass. They derive from the structural polymers-cellulose, hemicellulose and lignin. The formation of inhibitors depends on the pretreatment conditions. Inhibitors can have a negative influence on both the enzymatic hydrolysis and fermentation of lignocellulosic hydrolysates. The inhibition mechanisms can be, for example, deactivation of enzymes or impairment of vital cell structures. The toxicity of each inhibitor depends on its chemical and physical properties. To decrease the negative effects of inhibitors, different detoxification methods have been researched. Those methods focus on the chemical modification of inhibitors into less toxic forms or on the separation of inhibitors from lignocellulosic hydrolysates. Each detoxification method has its limitations on the removal of certain inhibitors. To choose a suitable detoxification method, a deep molecular understanding of the inhibition mechanism and the inhibitor formation is necessary.
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33
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Yadav N, Pranaw K, Khare SK. Screening of lactic acid bacteria stable in ionic liquids and lignocellulosic by-products for bio-based lactic acid production. ACTA ACUST UNITED AC 2020. [DOI: 10.1016/j.biteb.2020.100423] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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34
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van Dijk M, Mierke F, Nygård Y, Olsson L. Nutrient-supplemented propagation of Saccharomyces cerevisiae improves its lignocellulose fermentation ability. AMB Express 2020; 10:157. [PMID: 32857229 PMCID: PMC7455642 DOI: 10.1186/s13568-020-01070-y] [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: 06/02/2020] [Accepted: 07/18/2020] [Indexed: 12/21/2022] Open
Abstract
Propagation conditions have been shown to be of considerable importance for the fermentation ability of Saccharomyces cerevisiae. The limited tolerance of yeast to inhibitors present in lignocellulosic hydrolysates is a major challenge in second-generation bioethanol production. We have investigated the hypothesis that the addition of nutrients during propagation leads to yeast cultures with improved ability to subsequently ferment lignocellulosic materials. This hypothesis was tested with and without short-term adaptation to wheat straw or corn stover hydrolysates during propagation of the yeast. The study was performed using the industrial xylose-fermenting S. cerevisiae strain CR01. Adding a mixture of pyridoxine, thiamine, and biotin to unadapted propagation cultures improved cell growth and ethanol yields during fermentation in wheat straw hydrolysate from 0.04 g g−1 to 0.19 g g−1 and in corn stover hydrolysate from 0.02 g g−1 to 0.08 g g−1. The combination of short–term adaptation and supplementation with the vitamin mixture during propagation led to ethanol yields of 0.43 g g−1 in wheat straw hydrolysate fermentation and 0.41 g g−1 in corn stover hydrolysate fermentation. These ethanol yields were improved compared to ethanol yields from cultures that were solely short-term adapted (0.37 and 0.33 g g−1). Supplementing the propagation medium with nutrients in combination with short-term adaptation was thus demonstrated to be a promising strategy to improve the efficiency of industrial lignocellulosic fermentation.
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35
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Liang Z, Wang X, Bao X, Wei T, Hou J, Liu W, Shen Y. Newly identified genes contribute to vanillin tolerance in Saccharomyces cerevisiae. Microb Biotechnol 2020; 14:503-516. [PMID: 32729986 PMCID: PMC7936312 DOI: 10.1111/1751-7915.13643] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 07/05/2020] [Accepted: 07/13/2020] [Indexed: 12/12/2022] Open
Abstract
Exploring the mechanisms of tolerance in microorganisms to vanillin, which is derived from lignin, will benefit the design of robust cell factories that produce biofuels and chemicals using lignocellulosic materials. Our objective was to identify the genes related to vanillin tolerance in Saccharomyces cerevisiae. We investigated the effects on vanillin tolerance of several genes that have site mutations in the highly vanillin‐tolerant strain EMV‐8 compared to its parental line NAN‐27. The results showed that overexpression of GCY1, a gene that encodes an aldo‐keto reductase that also has mRNA‐binding activity, YPR1, a paralog of GCY1 that encodes an aldo‐keto reductase, PEX5, a gene that encodes a peroxisomal membrane signal receptor and MBF1, a gene that encodes a multiprotein bridging factor increase the specific growth rates (μ) by 49%, 41%, 44% and 48 %, respectively, in medium containing 6 mmol l−1 vanillin. Among these gene products, Gcy1p and Ypr1p showed NADPH‐dependent and NAD(P)H‐dependent vanillin reductase activity, respectively. The reductase‐inactive mutant Gcy1pY56F also increased vanillin tolerance in S. cerevisiae, suggesting that other mechanisms exist. Although TRS85 and PEX5, genes for which the mRNAs are binding targets of Gcy1p, were shown to be related to vanillin tolerance, both the mRNA and protein levels of these genes were not changed by overexpression of GCY1. The relationship between the mRNA‐binding activity of Gcy1p and its positive effect on vanillin tolerance is still not clear. Finally, we found that the point mutation D112A in Mbf1p, which disrupts the binding of Mbf1p and the TATA element‐binding protein (TBP), did not decrease the positive effect of Mbf1p on vanillin tolerance. This indicates that the binding of Mbf1p and TBP is not necessary for the positive effect on vanillin tolerance mediated by Mbf1p. We have successfully identified new genes related to vanillin tolerance and provided novel targets that can be used to improve the vanillin tolerance of S. cerevisiae. Moreover, we have extended our understanding of the proteins encoded by these genes.
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Affiliation(s)
- Zhenzhen Liang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Xinning Wang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, China.,State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qi Lu University of Technology, Jinan, 250353, China
| | - Xiaoming Bao
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, China.,State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qi Lu University of Technology, Jinan, 250353, China
| | - Tiandi Wei
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Jin Hou
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Yu Shen
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, China
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36
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Chen H, Li J, Wan C, Fang Q, Bai F, Zhao X. Improvement of inhibitor tolerance in Saccharomyces cerevisiae by overexpression of the quinone oxidoreductase family gene YCR102C. FEMS Yeast Res 2020; 19:5543220. [PMID: 31374572 DOI: 10.1093/femsyr/foz055] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 07/31/2019] [Indexed: 12/14/2022] Open
Abstract
Budding yeast Saccharomyces cerevisiae is widely used for lignocellulosic biorefinery. However, its fermentation efficiency is challenged by various inhibitors (e.g. weak acids, furfural) in the lignocellulosic hydrolysate, and acetic acid is commonly present as a major inhibitor. The effects of oxidoreductases on the inhibitor tolerance of S. cerevisiae have mainly focused on furfural and vanillin, whereas the influence of quinone oxidoreductase on acetic acid tolerance is still unknown. In this study, we show that overexpression of a quinone oxidoreductase-encoding gene, YCR102C, in S. cerevisiae, significantly enhanced ethanol production under acetic acid stress as well as in the inhibitor mixture, and also improved resistance to simultaneous stress of 40°C and 3.6 g/L acetic acid. Increased catalase activities, NADH/NAD+ ratio and contents of several metals, especially potassium, were observed by YCR102C overexpression under acetic acid stress. To our knowledge, this is the first report that the quinone oxidoreductase family protein is related to acid stress tolerance. Our study provides a novel strategy to increase lignocellulosic biorefinery efficiency using yeast cell factory.
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Affiliation(s)
- Hongqi Chen
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jie Li
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Chun Wan
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Qing Fang
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China
| | - Fengwu Bai
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xinqing Zhao
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
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37
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Substrate promiscuity of polyketide synthase enables production of tsetse fly attractants 3-ethylphenol and 3-propylphenol by engineering precursor supply in yeast. Sci Rep 2020; 10:9962. [PMID: 32561880 PMCID: PMC7305150 DOI: 10.1038/s41598-020-66997-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 06/01/2020] [Indexed: 11/09/2022] Open
Abstract
Tsetse flies are the transmitting vector of trypanosomes causing human sleeping sickness and animal trypanosomiasis in sub-saharan Africa. 3-alkylphenols are used as attractants in tsetse fly traps to reduce the spread of the disease. Here we present an inexpensive production method for 3-ethylphenol (3-EP) and 3-propylphenol (3-PP) by microbial fermentation of sugars. Heterologous expression in the yeast Saccharomyces cerevisiae of phosphopantetheinyltransferase-activated 6-methylsalicylic acid (6-MSA) synthase (MSAS) and 6-MSA decarboxylase converted acetyl-CoA as a priming unit via 6-MSA into 3-methylphenol (3-MP). We exploited the substrate promiscuity of MSAS to utilize propionyl-CoA and butyryl-CoA as alternative priming units and the substrate promiscuity of 6-MSA decarboxylase to produce 3-EP and 3-PP in yeast fermentations. Increasing the formation of propionyl-CoA by expression of a bacterial propionyl-CoA synthetase, feeding of propionate and blocking propionyl-CoA degradation led to the production of up to 12.5 mg/L 3-EP. Introduction of a heterologous 'reverse ß-oxidation' pathway provided enough butyryl-CoA for the production of 3-PP, reaching titers of up to 2.6 mg/L. As the concentrations of 3-alkylphenols are close to the range of the concentrations deployed in tsetse fly traps, the yeast broths might become promising and inexpensive sources for attractants, producible on site by rural communities in Africa.
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38
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Kuang X, Ouyang Y, Guo Y, Li Q, Wang H, Abrha GT, Ayepa E, Gu Y, Li X, Chen Q, Ma M. New insights into two yeast BDHs from the PDH subfamily as aldehyde reductases in context of detoxification of lignocellulosic aldehyde inhibitors. Appl Microbiol Biotechnol 2020; 104:6679-6692. [PMID: 32556414 DOI: 10.1007/s00253-020-10722-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 05/25/2020] [Accepted: 06/04/2020] [Indexed: 12/30/2022]
Abstract
At least 24 aldehyde reductases from Saccharomyces cerevisiae have been characterized and most function in in situ detoxification of lignocellulosic aldehyde inhibitors, but none is classified into the polyol dehydrogenase (PDH) subfamily of the medium-chain dehydrogenase/reductase (MDR) superfamily. This study confirmed that two (2R,3R)-2,3-butanediol dehydrogenases (BDHs) from industrial (denoted Y)/laboratory (denoted B) strains of S. cerevisiae, Bdh1p(Y)/Bdh1p(B) and Bdh2p(Y)/Bdh2p(B), were members of the PDH subfamily with an NAD(P)H binding domain and a catalytic zinc binding domain, and exhibited reductive activities towards lignocellulosic aldehyde inhibitors, such as acetaldehyde, glycolaldehyde, and furfural. Especially, the highest enzyme activity towards acetaldehyde by Bdh2p(Y) was 117.95 U/mg with cofactor nicotinamide adenine dinucleotide reduced (NADH). Based on the comparative kinetic property analysis, Bdh2p(Y)/Bdh2p(B) possessed higher specific activity, substrate affinity, and catalytic efficiency towards glycolaldehyde than Bdh1p(Y)/Bdh1p(B). This was speculated to be related to their 49% sequence differences and five nonsynonymous substitutions (Ser41Thr, Glu173Gln, Ile270Leu, Ile316Met, and Gly317Cys) occurred in their conserved NAD(P)H binding domains. Compared with BDHs from a laboratory strain, Bdh1p(Y) and Bdh2p(Y) from an industrial strain displayed five nonsynonymous mutations (Thr12, Asn61, Glu168, Val222, and Ala235) and three nonsynonymous mutations (Ala34, Ile96, and Ala369), respectively. From a first analysis with selected aldehydes, their reductase activities were different from BDHs of laboratory strain, and their catalytic efficiency was higher towards glycolaldehyde and lower towards acetaldehyde. Comparative investigation of kinetic properties of BDHs from S. cerevisiae as aldehyde reductases provides a guideline for their practical applications in in situ detoxification of aldehyde inhibitors during lignocellulose bioconversion.Key Points• Two yeast BDHs have enzyme activities for reduction of aldehydes.• Overexpression of BDHs slightly improves yeast tolerance to acetaldehyde and glycolaldehyde.• Bdh1p and Bdh2p differ in enzyme kinetic properties.• BDHs from strains with different genetic backgrounds differ in enzyme kinetic properties.
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Affiliation(s)
- Xiaolin Kuang
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China
| | - Yidan Ouyang
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China
| | - Yaping Guo
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China.,Patent Examination Cooperation Sichuan Center of the Patent Office, SIPO, Chengdu, 610213, Sichuan, People's Republic of China
| | - Qian Li
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China
| | - Hanyu Wang
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China
| | - Getachew Tafere Abrha
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China
| | - Ellen Ayepa
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China
| | - Yunfu Gu
- Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China
| | - Xi Li
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China
| | - Qiang Chen
- Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China
| | - Menggen Ma
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, No. 211 Huimin Road, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China. .,Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, People's Republic of China.
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39
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Mahboubi A, Elyasi S, Doyen W, De Wever H, Taherzadeh MJ. Concentration-driven reverse membrane bioreactor for the fermentation of highly inhibitory lignocellulosic hydrolysate. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.01.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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40
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Hu X, Han X, Wu L, Wang H, Ouyang Y, Li Q, Kuang X, Xiang Q, Yu X, Li X, Gu Y, Zhao K, Chen Q, Ma M. The open reading frame 02797 from Candida tropicalis encodes a novel NADH-dependent aldehyde reductase. Protein Expr Purif 2020; 171:105625. [PMID: 32173567 DOI: 10.1016/j.pep.2020.105625] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 03/10/2020] [Accepted: 03/10/2020] [Indexed: 12/17/2022]
Abstract
Owing to its high-temperature tolerance, robustness, and wide use of carbon sources, Candida tropicalis is considered a good candidate microorganism for bioconversion of lignocellulose to ethanol. It also has the intrinsic ability to in situ detoxify aldehydes derived from lignocellulosic hydrolysis. However, the aldehyde reductases that catalyze this bioconversion in C. tropicalis remain unknown. Herein, we found that the uncharacterized open reading frame (ORF), CTRG_02797, from C. tropicalis encodes a novel and broad substrate-specificity aldehyde reductase that reduces at least seven aldehydes. This enzyme strictly depended on NADH rather than NADPH as the co-factor for catalyzing the reduction reaction. Its highest affinity (Km), maximum velocity (Vmax), catalytic rate constant (Kcat), and catalytic efficiency (Kcat/Km) were observed when reducing acetaldehyde (AA) and its enzyme activity was influenced by different concentrations of salts, metal ions, and chemical protective additives. Protein localization assay demonstrated that Ctrg_02797p was localized in the cytoplasm in C. tropicalis cells, which ensures an effective enzymatic reaction. Finally, Ctrg_02797p was grouped into the cinnamyl alcohol dehydrogenase (CADH) subfamily of the medium-chain dehydrogenase/reductase family. This research provides guidelines for exploring more uncharacterized genes with reduction activity for detoxifying aldehydes.
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Affiliation(s)
- Xiangdong Hu
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Xuebing Han
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Lan Wu
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Hanyu Wang
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Yidan Ouyang
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Qian Li
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Xiaolin Kuang
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Quanju Xiang
- Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Xiumei Yu
- Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Xi Li
- College of Landscape Architecture, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Yunfu Gu
- Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Ke Zhao
- Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Qiang Chen
- Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China
| | - Menggen Ma
- Institute of Resources and Geographic Information Technology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China; Department of Applied Microbiology, College of Resources, Sichuan Agricultural University, Wenjiang, Chengdu, 611130, Sichuan, PR China.
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41
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Biocatalytic reduction of 5-hydroxymethylfurfural to 2,5-furandimethanol using coconut (Cocos nucifera L.) water. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2020. [DOI: 10.1016/j.bcab.2020.101551] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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42
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Dielectric property measurements as a method to determine the physiological state of Kluyveromyces marxianus and Saccharomyces cerevisiae stressed with furan aldehydes. Appl Microbiol Biotechnol 2019; 103:9633-9642. [DOI: 10.1007/s00253-019-10152-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 09/06/2019] [Accepted: 09/22/2019] [Indexed: 02/07/2023]
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43
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Effective diffusion coefficients and bioconversion rates of inhibitory compounds in flocs of Saccharomyces cerevisiae. ELECTRON J BIOTECHN 2019. [DOI: 10.1016/j.ejbt.2019.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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44
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Luziatelli F, Brunetti L, Ficca AG, Ruzzi M. Maximizing the Efficiency of Vanillin Production by Biocatalyst Enhancement and Process Optimization. Front Bioeng Biotechnol 2019; 7:279. [PMID: 31681753 PMCID: PMC6813415 DOI: 10.3389/fbioe.2019.00279] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 10/03/2019] [Indexed: 01/20/2023] Open
Abstract
The rising demand of bio-vanillin and the possibility to use microbial biotransformation to produce this compound from agroindustrial byproducts are economically attractive. However, there are still several bottlenecks, including substrate and product toxicity, formation of undesired products and genetic stability of the recombinant strains, that impede an efficient use of recombinant Escherichia coli strains to make the whole process cost effective. To overcome these problems, we developed a new E. coli strain, named FR13, carrying the Pseudomonas genes encoding feruloyl-CoA synthetase and feruloyl-CoA hydratase/aldolase integrated into the chromosome and, using resting cells, we demonstrated that the vanillin yield and selectivity were strongly affected by the physiological state of the cells, the temperature used for the growth and the recovery of the biomass and the composition and pH of the bioconversion buffer. The substrate consumption rate and the vanillin yield increased using a sodium/potassium phosphate buffer at pH 9.0 as bioconversion medium. Optimization of the bioprocess variables, using response surface methodology, together with the use of a two-phase (solid-liquid) system for the controlled release of ferulic acid allowed us to increase the vanillin yield up to 28.10 ± 0.05 mM. These findings showed that recombinant plasmid-free E. coli strains are promising candidates for the production of vanillin at industrial scale and that a reduction of the cost of the bioconversion process requires approaches that minimize the toxicity of both ferulic acid and vanillin.
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Affiliation(s)
| | | | | | - Maurizio Ruzzi
- Department for Innovation in Biological, Agro-Food and Forest Systems (DIBAF), University of Tuscia, Viterbo, Italy
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45
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Feldman D, Kowbel DJ, Cohen A, Glass NL, Hadar Y, Yarden O. Identification and manipulation of Neurospora crassa genes involved in sensitivity to furfural. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:210. [PMID: 31508149 PMCID: PMC6724289 DOI: 10.1186/s13068-019-1550-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 08/24/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Biofuels derived from lignocellulosic biomass are a viable alternative to fossil fuels required for transportation. Following plant biomass pretreatment, the furan derivative furfural is present at concentrations which are inhibitory to yeasts. Detoxification of furfural is thus important for efficient fermentation. Here, we searched for new genetic attributes in the fungus Neurospora crassa that may be linked to furfural tolerance. The fact that furfural is involved in the natural process of sexual spore germination of N. crassa and that this fungus is highly amenable to genetic manipulations makes it a rational candidate for this study. RESULTS Both hypothesis-based and unbiased (random promotor mutagenesis) approaches were performed to identify N. crassa genes associated with the response to furfural. Changes in the transcriptional profile following exposure to furfural revealed that the affected processes were, overall, similar to those observed in Saccharomyces cerevisiae. N. crassa was more tolerant (by ~ 30%) to furfural when carboxymethyl cellulose was the main carbon source as opposed to sucrose, indicative of a link between carbohydrate metabolism and furfural tolerance. We also observed increased tolerance in a Δcre-1 mutant (CRE-1 is a key transcription factor that regulates the ability of fungi to utilize non-preferred carbon sources). In addition, analysis of aldehyde dehydrogenase mutants showed that ahd-2 (NCU00378) was involved in tolerance to furfural as well as the predicted membrane transporter NCU05580 (flr-1), a homolog of FLR1 in S. cerevisiae. Further to the rational screening, an unbiased approach revealed additional genes whose inactivation conferred increased tolerance to furfural: (i) NCU02488, which affected the abundance of the non-anchored cell wall protein NCW-1 (NCU05137), and (ii) the zinc finger protein NCU01407. CONCLUSIONS We identified attributes in N. crassa associated with tolerance or degradation of furfural, using complementary research approaches. The manipulation of the genes involved in furan sensitivity can provide a means for improving the production of biofuel producing strains. Similar research approaches can be utilized in N. crassa and other filamentous fungi to identify additional attributes relevant to other furans or toxic chemicals.
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Affiliation(s)
- Daria Feldman
- Department of Plant Pathology and Microbiology, The R.H. Smith Faculty Agriculture, Food and Environment, The Hebrew University of Jerusalem, 7600001 Rehovot, Israel
| | - David J. Kowbel
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720 USA
| | - Adi Cohen
- Department of Plant Pathology and Microbiology, The R.H. Smith Faculty Agriculture, Food and Environment, The Hebrew University of Jerusalem, 7600001 Rehovot, Israel
| | - N. Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720 USA
- Environmental Genomics and Systems Biology Division, The Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 USA
| | - Yitzhak Hadar
- Department of Plant Pathology and Microbiology, The R.H. Smith Faculty Agriculture, Food and Environment, The Hebrew University of Jerusalem, 7600001 Rehovot, Israel
| | - Oded Yarden
- Department of Plant Pathology and Microbiology, The R.H. Smith Faculty Agriculture, Food and Environment, The Hebrew University of Jerusalem, 7600001 Rehovot, Israel
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46
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Kim S, Lee J, Sung BH. Isolation and Characterization of the Stress-Tolerant Candida tropicalis YHJ1 and Evaluation of Its Xylose Reductase for Xylitol Production From Acid Pre-treatment Wastewater. Front Bioeng Biotechnol 2019; 7:138. [PMID: 31338365 PMCID: PMC6626919 DOI: 10.3389/fbioe.2019.00138] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 05/22/2019] [Indexed: 11/13/2022] Open
Abstract
A stress-tolerant yeast was isolated from honey using acid hydrolysate generated from sequential acid-/alkali-pretreatment of empty palm fruit bunch fiber (EPFBF). The isolated yeast was identified molecularly, taxonomically, and morphologically as Candida tropicalis YHJ1, and analyzed for application in xylitol production. The isolated yeast showed stress tolerance toward various chemical reagents and could grow with up to 600 g/L xylose in the culture medium. This yeast also had a broad carbohydrate utilization spectrum, and its xylitol yield was greatest in medium supplemented with xylose as the sole carbon source. In batch fermentation for xylitol production, the yeast could convert xylose prepared from acidic EPFBF pretreatment wastewater into xylitol. Interestingly, C. tropicalis YHJ1 xylose reductase, containing a Ser279 residue, exhibited more effective xylitol conversion compared to orthologous Candida enzymes containing Leu279 or Asn279; this improvement was associated with NADPH binding, as predicted through homologous structure modeling and enzyme kinetic analysis. Taken together, these results show a novel stress-tolerant yeast strain that may be applicable to xylitol production from toxic lignocellulosic byproducts.
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Affiliation(s)
- Seonghun Kim
- Jeonbuk Branch Institute, Korea Research Institute of Bioscience and Biotechnology, Jeongeup, South Korea.,Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology, Daejeon, South Korea
| | - Jinhyuk Lee
- Genome Editing Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea.,Department of Bioinformatics, KRIBB School of Bioscience, University of Science and Technology, Daejeon, South Korea
| | - Bong Hyun Sung
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea.,Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology, Daejeon, South Korea
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47
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Zhou P, Yao R, Zhang H, Bao J. Unique glucose oxidation catalysis of
Gluconobacter oxydans
constitutes an efficient cellulosic gluconic acid fermentation free of inhibitory compounds disturbance. Biotechnol Bioeng 2019; 116:2191-2199. [DOI: 10.1002/bit.27020] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 04/14/2019] [Accepted: 05/09/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Pingping Zhou
- School of BioengineeringState Key Laboratory of Bioreactor Engineering, East China University of Science and TechnologyShanghai China
| | - Ruimiao Yao
- School of BioengineeringState Key Laboratory of Bioreactor Engineering, East China University of Science and TechnologyShanghai China
| | - Hongsen Zhang
- School of BioengineeringState Key Laboratory of Bioreactor Engineering, East China University of Science and TechnologyShanghai China
- Key Laboratory of Enzyme Engineering of Agricultural MicrobiologyMinistry of AgricultureCollege of Life ScienceHenan Agricultural UniversityZhengzhou China
| | - Jie Bao
- School of BioengineeringState Key Laboratory of Bioreactor Engineering, East China University of Science and TechnologyShanghai China
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48
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Protein expression analysis revealed a fine-tuned mechanism of in situ detoxification pathway for the tolerant industrial yeast Saccharomyces cerevisiae. Appl Microbiol Biotechnol 2019; 103:5781-5796. [PMID: 31139900 DOI: 10.1007/s00253-019-09906-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 05/07/2019] [Accepted: 05/07/2019] [Indexed: 12/18/2022]
Abstract
Inhibitory compounds liberated from lignocellulose pretreatment are representative toxic chemicals that repress microbial growth and metabolism. A tolerant strain of the industrial yeast Saccharomyces cerevisiae is able to detoxify a major class of toxic compounds while producing ethanol. Knowledge on the yeast tolerance was mostly obtained by gene expression analysis and limited protein expression evidence is yet available underlying the yeast adaptation. Here we report a comparative protein expression profiling study on Y-50049, a tolerant strain compared with its parental industrial type strain Y-12632. We found a distinctive protein expression of glucose-6-phosphate dehydrogenase (Zwf1) in Y-50049 but not in Y-12632, in the relatively conserved glycolysis and pentose phosphate pathway (PPP) in response to a combinational challenge of 2-furaldehyde (furfural) and 5-hydroxymethyl-2-furaldehyde (HMF). A group of proteins with aldehyde reduction activity was uniquely induced expressed in Y-50049 but not in Y-12632. Such evidence allowed fine-tuning a mechanism of the renovated in situ detoxification by Y-50049. As the key protein, Zwf1 drove the glucose metabolism in favor of the oxidative branch of the PPP facilitating in situ detoxification of the toxic chemicals by Y-50049. The activated expression of Zwf1 generated the essential cofactor nicotinamide adenine dinucleotide phosphate (NADPH) enabling reduction of furfural and HMF through a group of aldehyde reduction enzymes. In return, the activate aldehyde reductions released desirable feedbacks of NADP+ stimulating continued oxidative activity of Zwf1. Thus, a well-maintained cofactor regeneration cycle was established to restore the cofactor imbalance caused by furfural-HMF. Challenges and perspectives on adaptation of significantly differential expressions of ribosomal proteins and other unique proteins are also discussed.
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49
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Wang H, Li Q, Zhang Z, Zhou C, Ayepa E, Abrha GT, Han X, Hu X, Yu X, Xiang Q, Li X, Gu Y, Zhao K, Xie C, Chen Q, Ma M. YKL107W from Saccharomyces cerevisiae encodes a novel aldehyde reductase for detoxification of acetaldehyde, glycolaldehyde, and furfural. Appl Microbiol Biotechnol 2019; 103:5699-5713. [DOI: 10.1007/s00253-019-09885-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 04/24/2019] [Accepted: 04/29/2019] [Indexed: 02/05/2023]
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50
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Yi X, Gao Q, Zhang L, Wang X, He Y, Hu F, Zhang J, Zou G, Yang S, Zhou Z, Bao J. Heterozygous diploid structure of Amorphotheca resinae ZN1 contributes efficient biodetoxification on solid pretreated corn stover. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:126. [PMID: 31139256 PMCID: PMC6528196 DOI: 10.1186/s13068-019-1466-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Accepted: 05/10/2019] [Indexed: 05/31/2023]
Abstract
BACKGROUND Fast, complete, and ultimate removal of inhibitory compounds derived from lignocellulose pretreatment is the prerequisite for efficient production of cellulosic ethanol and biochemicals. Biodetoxification is the most promising method for inhibitor removal by its unique advantages. The biodetoxification mechanisms of a unique diploid fungus responsible for highly efficient biodetoxification in solid-state culture was extensively investigated in the aspects of cellular structure, genome sequencing, transcriptome analysis, and practical biodetoxification. RESULTS The inborn heterozygous diploid structure of A. resinae ZN1 uniquely contributed to the enhancement of inhibitor tolerance and conversion. The co-expression of gene pairs contributed to the enhancement of the degradation of lignocellulose-derived model inhibitors. The ultimate inhibitors degradation pathways and sugar conservation were elucidated by microbial degradation experimentation as well as the genomic and transcriptomic sequencing analysis. CONCLUSIONS The finding of the heterozygous diploid structure in A. resinae ZN1 on biodetoxification took the first insight into the global overview of biodetoxification mechanism of lignocellulose-derived inhibitors. This study provided a unique and practical biodetoxification biocatalyst of inhibitor compounds for lignocellulose biorefinery processing, as well as the synthetic biology tools on biodetoxification of biorefinery fermenting strains.
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Affiliation(s)
- Xia Yi
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237 China
- Jiangxi Provincial Laboratory of Systems Biomedicine, Jiujiang University, 17 Lufeng Road, Jiujiang, 332000 China
| | - Qiuqiang Gao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237 China
| | - Lei Zhang
- CAS Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032 China
| | - Xia Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237 China
- Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Yanqing He
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237 China
| | - Fengxian Hu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237 China
| | - Jian Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237 China
| | - Gen Zou
- CAS Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032 China
| | - Shihui Yang
- Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Zhihua Zhou
- CAS Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032 China
| | - Jie Bao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237 China
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