1
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Han J, Wang X, Niu S. Genome-Wide Identification of 2-Oxoglutarate and Fe (II)-Dependent Dioxygenase (2ODD-C) Family Genes and Expression Profiles under Different Abiotic Stresses in Camellia sinensis (L.). PLANTS (BASEL, SWITZERLAND) 2023; 12:1302. [PMID: 36986990 PMCID: PMC10051519 DOI: 10.3390/plants12061302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 02/27/2023] [Accepted: 03/11/2023] [Indexed: 06/19/2023]
Abstract
The 2-oxoglutarate and Fe (II)-dependent dioxygenase (2ODD-C) family of 2-oxoglutarate-dependent dioxygenases potentially participates in the biosynthesis of various metabolites under various abiotic stresses. However, there is scarce information on the expression profiles and roles of 2ODD-C genes in Camellia sinensis. We identified 153 Cs2ODD-C genes from C. sinensis, and they were distributed unevenly on 15 chromosomes. According to the phylogenetic tree topology, these genes were divided into 21 groups distinguished by conserved motifs and an intron/exon structure. Gene-duplication analyses revealed that 75 Cs2ODD-C genes were expanded and retained after WGD/segmental and tandem duplications. The expression profiles of Cs2ODD-C genes were explored under methyl jasmonate (MeJA), polyethylene glycol (PEG), and salt (NaCl) stress treatments. The expression analysis showed that 14, 13, and 49 Cs2ODD-C genes displayed the same expression pattern under MeJA and PEG treatments, MeJA and NaCl treatments, and PEG and NaCl treatments, respectively. A further analysis showed that two genes, Cs2ODD-C36 and Cs2ODD-C21, were significantly upregulated and downregulated after MeJA, PEG, and NaCl treatments, indicating that these two genes played positive and negative roles in enhancing the multi-stress tolerance. These results provide candidate genes for the use of genetic engineering technology to modify plants by enhancing multi-stress tolerance to promote phytoremediation efficiency.
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2
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Mierke F, Brink DP, Norbeck J, Siewers V, Andlid T. Functional genome annotation and transcriptome analysis of Pseudozyma hubeiensis BOT-O, an oleaginous yeast that utilizes glucose and xylose at equal rates. Fungal Genet Biol 2023; 166:103783. [PMID: 36870442 DOI: 10.1016/j.fgb.2023.103783] [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: 05/06/2022] [Revised: 02/10/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023]
Abstract
Pseudozyma hubeiensis is a basidiomycete yeast that has the highly desirable traits for lignocellulose valorisation of being equally efficient at utilization of glucose and xylose, and capable of their co-utilization. The species has previously mainly been studied for its capacity to produce secreted biosurfactants in the form of mannosylerythritol lipids, but it is also an oleaginous species capable of accumulating high levels of triacylglycerol storage lipids during nutrient starvation. In this study, we aimed to further characterize the oleaginous nature of P. hubeiensis by evaluating metabolism and gene expression responses during storage lipid formation conditions with glucose or xylose as a carbon source. The genome of the recently isolated P. hubeiensis BOT-O strain was sequenced using MinION long-read sequencing and resulted in the most contiguous P. hubeiensis assembly to date with 18.95 Mb in 31 contigs. Using transcriptome data as experimental support, we generated the first mRNA-supported P. hubeiensis genome annotation and identified 6540 genes. 80% of the predicted genes were assigned functional annotations based on protein homology to other yeasts. Based on the annotation, key metabolic pathways in BOT-O were reconstructed, including pathways for storage lipids, mannosylerythritol lipids and xylose assimilation. BOT-O was confirmed to consume glucose and xylose at equal rates, but during mixed glucose-xylose cultivation glucose was found to be taken up faster. Differential expression analysis revealed that only a total of 122 genes were significantly differentially expressed at a cut-off of |log2 fold change| ≥ 2 when comparing cultivation on xylose with glucose, during exponential growth and during nitrogen-starvation. Of these 122 genes, a core-set of 24 genes was identified that were differentially expressed at all time points. Nitrogen-starvation resulted in a larger transcriptional effect, with a total of 1179 genes with significant expression changes at the designated fold change cut-off compared with exponential growth on either glucose or xylose.
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Affiliation(s)
- Friederike Mierke
- Food and Nutrition Science, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden; Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
| | - Daniel P Brink
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden; Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden
| | - Joakim Norbeck
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
| | - Verena Siewers
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden.
| | - Thomas Andlid
- Food and Nutrition Science, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
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3
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Geijer C, Faria-Oliveira F, Moreno AD, Stenberg S, Mazurkewich S, Olsson L. Genomic and transcriptomic analysis of Candida intermedia reveals the genetic determinants for its xylose-converting capacity. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:48. [PMID: 32190113 PMCID: PMC7068945 DOI: 10.1186/s13068-020-1663-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 01/21/2020] [Indexed: 05/05/2023]
Abstract
BACKGROUND An economically viable production of biofuels and biochemicals from lignocellulose requires microorganisms that can readily convert both the cellulosic and hemicellulosic fractions into product. The yeast Candida intermedia displays a high capacity for uptake and conversion of several lignocellulosic sugars including the abundant pentose d-xylose, an underutilized carbon source since most industrially relevant microorganisms cannot naturally ferment it. Thus, C. intermedia constitutes an important source of knowledge and genetic information that could be transferred to industrial microorganisms such as Saccharomyces cerevisiae to improve their capacity to ferment lignocellulose-derived xylose. RESULTS To understand the genetic determinants that underlie the metabolic properties of C. intermedia, we sequenced the genomes of both the in-house-isolated strain CBS 141442 and the reference strain PYCC 4715. De novo genome assembly and subsequent analysis revealed C. intermedia to be a haploid species belonging to the CTG clade of ascomycetous yeasts. The two strains have highly similar genome sizes and number of protein-encoding genes, but they differ on the chromosomal level due to numerous translocations of large and small genomic segments. The transcriptional profiles for CBS 141442 grown in medium with either high or low concentrations of glucose and xylose were determined through RNA-sequencing analysis, revealing distinct clusters of co-regulated genes in response to different specific growth rates, carbon sources and osmotic stress. Analysis of the genomic and transcriptomic data also identified multiple xylose reductases, one of which displayed dual NADH/NADPH co-factor specificity that likely plays an important role for co-factor recycling during xylose fermentation. CONCLUSIONS In the present study, we performed the first genomic and transcriptomic analysis of C. intermedia and identified several novel genes for conversion of xylose. Together the results provide insights into the mechanisms underlying saccharide utilization in C. intermedia and reveal potential target genes to aid in xylose fermentation in S. cerevisiae.
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Affiliation(s)
- Cecilia Geijer
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Fábio Faria-Oliveira
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Antonio D. Moreno
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
- Present Address: Biofuels Unit, Department of Energy, CIEMAT, Madrid, Spain
| | - Simon Stenberg
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Scott Mazurkewich
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Lisbeth Olsson
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
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4
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Tiukova IA, Brandenburg J, Blomqvist J, Sampels S, Mikkelsen N, Skaugen M, Arntzen MØ, Nielsen J, Sandgren M, Kerkhoven EJ. Proteome analysis of xylose metabolism in Rhodotorula toruloides during lipid production. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:137. [PMID: 31171938 PMCID: PMC6547517 DOI: 10.1186/s13068-019-1478-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 05/25/2019] [Indexed: 05/28/2023]
Abstract
BACKGROUND Rhodotorula toruloides is a promising platform organism for production of lipids from lignocellulosic substrates. Little is known about the metabolic aspects of lipid production from the lignocellolosic sugar xylose by oleaginous yeasts in general and R. toruloides in particular. This study presents the first proteome analysis of the metabolism of R. toruloides during conversion of xylose to lipids. RESULTS Rhodotorula toruloides cultivated on either glucose or xylose was subjected to comparative analysis of its growth dynamics, lipid composition, fatty acid profiles and proteome. The maximum growth and sugar uptake rate of glucose-grown R. toruloides cells were almost twice that of xylose-grown cells. Cultivation on xylose medium resulted in a lower final biomass yield although final cellular lipid content was similar between glucose- and xylose-grown cells. Analysis of lipid classes revealed the presence of monoacylglycerol in the early exponential growth phase as well as a high proportion of free fatty acids. Carbon source-specific changes in lipid profiles were only observed at early exponential growth phase, where C18 fatty acids were more saturated in xylose-grown cells. Proteins involved in sugar transport, initial steps of xylose assimilation and NADPH regeneration were among the proteins whose levels increased the most in xylose-grown cells across all time points. The levels of enzymes involved in the mevalonate pathway, phospholipid biosynthesis and amino acids biosynthesis differed in response to carbon source. In addition, xylose-grown cells contained higher levels of enzymes involved in peroxisomal beta-oxidation and oxidative stress response compared to cells cultivated on glucose. CONCLUSIONS The results obtained in the present study suggest that sugar import is the limiting step during xylose conversion by R. toruloides into lipids. NADPH appeared to be regenerated primarily through pentose phosphate pathway although it may also involve malic enzyme as well as alcohol and aldehyde dehydrogenases. Increases in enzyme levels of both fatty acid biosynthesis and beta-oxidation in xylose-grown cells was predicted to result in a futile cycle. The results presented here are valuable for the development of lipid production processes employing R. toruloides on xylose-containing substrates.
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Affiliation(s)
- Ievgeniia A. Tiukova
- Systems and Synthetic Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Göteborg, Sweden
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Jule Brandenburg
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Johanna Blomqvist
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
- Faculty of Science and Technology, Norwegian University of Life Sciences, Ås, Norway
| | - Sabine Sampels
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Nils Mikkelsen
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Morten Skaugen
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway
| | - Magnus Ø. Arntzen
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Ås, Norway
| | - Jens Nielsen
- Systems and Synthetic Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Göteborg, Sweden
| | - Mats Sandgren
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Eduard J. Kerkhoven
- Systems and Synthetic Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Göteborg, Sweden
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5
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Zhu K, Li G, Wei R, Mao Y, Zhao Y, He A, Bai Z, Deng Y. Systematic analysis of the effects of different nitrogen source and ICDH knockout on glycolate synthesis in Escherichia coli. J Biol Eng 2019; 13:30. [PMID: 30988698 PMCID: PMC6449901 DOI: 10.1186/s13036-019-0159-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 03/26/2019] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Glycolate is an important α-hydroxy carboxylic acid widely used in industrial and consumer applications. The production of glycolate from glucose in Escherichia coli is generally carried out by glycolysis and glyoxylate shunt pathways, followed by reduction to glycolate. Glycolate accumulation was significantly affected by nitrogen sources and isocitrate dehydrogenase (ICDH), which influenced carbon flux distribution between the tricarboxylic acid (TCA) cycle and the glyoxylate shunt, however, the mechanism was unclear. RESULTS Herein, we used RNA-Seq to explore the effects of nitrogen sources and ICDH knockout on glycolate production. The Mgly534 strain and the Mgly624 strain (with the ICDH deletion in Mgly534), displaying different phenotypes on organic nitrogen sources, were also adopted for the exploration. Though the growth of Mgly534 was improved on organic nitrogen sources, glycolate production decreased and acetate accumulated, while Mgly624 achieved a balance between cell growth and glycolate production, reaching 0.81 g glycolate/OD (2.6-fold higher than Mgly534). To further study Mgly624, the significant changed genes related to N-regulation, oxidative stress response and iron transport were analyzed. Glutamate and serine were found to increase the biomass and productivity respectively. Meanwhile, overexpressing the arginine transport gene argT accelerated the cell growth rate and increased the biomass. Further, the presence of Fe2+ also speeded up the cells growth and compensated for the lack of reducing equivalents. CONCLUSION Our studies identified that ICDH knockout strain was more suitable for glycolate production. RNA-Seq provided a better understanding of the ICDH knockout on cellular physiology and glycolate production.
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Affiliation(s)
- Kangjia Zhu
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), Jiangnan University, 1800 Lihu Road, Wuxi, 214122 Jiangsu China
- School of Biotechnology, Jiangnan University, 1800 Lihu Rd, Wuxi, 214122 Jiangsu China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
| | - Guohui Li
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), Jiangnan University, 1800 Lihu Road, Wuxi, 214122 Jiangsu China
- School of Biotechnology, Jiangnan University, 1800 Lihu Rd, Wuxi, 214122 Jiangsu China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
| | - Ren Wei
- Institute of Biochemistry, Leipzig University, Johannisallee 23, D-04103 Leipzig, Germany
| | - Yin Mao
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), Jiangnan University, 1800 Lihu Road, Wuxi, 214122 Jiangsu China
- School of Biotechnology, Jiangnan University, 1800 Lihu Rd, Wuxi, 214122 Jiangsu China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
| | - Yunying Zhao
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), Jiangnan University, 1800 Lihu Road, Wuxi, 214122 Jiangsu China
- School of Biotechnology, Jiangnan University, 1800 Lihu Rd, Wuxi, 214122 Jiangsu China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
| | - Aiyong He
- Jiangsu Key Laboratory for Biomass-based Energy and Enzyme Technology, Huaiyin Normal University, Huaian, 223300 China
| | - Zhonghu Bai
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), Jiangnan University, 1800 Lihu Road, Wuxi, 214122 Jiangsu China
- School of Biotechnology, Jiangnan University, 1800 Lihu Rd, Wuxi, 214122 Jiangsu China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
| | - Yu Deng
- National Engineering Laboratory for Cereal Fermentation Technology (NELCF), Jiangnan University, 1800 Lihu Road, Wuxi, 214122 Jiangsu China
- School of Biotechnology, Jiangnan University, 1800 Lihu Rd, Wuxi, 214122 Jiangsu China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122 Jiangsu China
- Jiangsu Key Laboratory for Biomass-based Energy and Enzyme Technology, Huaiyin Normal University, Huaian, 223300 China
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6
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Production of biofuels and chemicals from xylose using native and engineered yeast strains. Biotechnol Adv 2018; 37:271-283. [PMID: 30553928 DOI: 10.1016/j.biotechadv.2018.12.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 11/13/2018] [Accepted: 12/12/2018] [Indexed: 11/20/2022]
Abstract
Numerous metabolic engineering strategies have allowed yeasts to efficiently assimilate xylose, the second most abundant sugar component of lignocellulosic biomass. During the investigation of xylose utilization by yeasts, a global rewiring of metabolic networks upon xylose cultivation has been captured, as opposed to a pattern of glucose repression. A clear understanding of the xylose-induced metabolic reprogramming in yeast would shed light on the optimization of yeast-based bioprocesses to produce biofuels and chemicals using xylose. In this review, we delved into the characteristics of yeast xylose metabolism, and potential benefits of using xylose as a carbon source to produce various biochemicals with examples. Transcriptomic and metabolomic patterns of xylose-grown yeast cells were distinct from those on glucose-a conventional sugar of industrial biotechnology-and the gap might lead to opportunities to produce biochemicals efficiently. Indeed, limited glycolytic metabolic fluxes during xylose utilization could result in enhanced production of metabolites whose biosynthetic pathways compete for precursors with ethanol fermentation. Also, alleviation of glucose repression on cytosolic acetyl coenzyme A (acetyl-CoA) synthesis, and respiratory energy metabolism during xylose utilization enhanced production of acetyl-CoA derivatives. Consideration of singular properties of xylose metabolism, such as redox cofactor imbalance between xylose reductase and xylitol dehydrogenase, is necessary to maximize these positive xylose effects. This review argues the importance and benefits of xylose utilization as not only a way of expanding a substrate range, but also an effective environmental perturbation for the efficient production of advanced biofuels and chemicals in yeasts.
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7
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Xu Q, Fu Y, Li S, Jiang L, Rongfeng G, Huang H. Integrated transcriptomic and metabolomic analysis of Rhizopus oryzae with different morphologies. Process Biochem 2018. [DOI: 10.1016/j.procbio.2017.10.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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8
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Gorochowski TE, Espah Borujeni A, Park Y, Nielsen AA, Zhang J, Der BS, Gordon DB, Voigt CA. Genetic circuit characterization and debugging using RNA-seq. Mol Syst Biol 2017; 13:952. [PMID: 29122925 PMCID: PMC5731345 DOI: 10.15252/msb.20167461] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Genetic circuits implement computational operations within a cell. Debugging them is difficult because their function is defined by multiple states (e.g., combinations of inputs) that vary in time. Here, we develop RNA‐seq methods that enable the simultaneous measurement of: (i) the states of internal gates, (ii) part performance (promoters, insulators, terminators), and (iii) impact on host gene expression. This is applied to a three‐input one‐output circuit consisting of three sensors, five NOR/NOT gates, and 46 genetic parts. Transcription profiles are obtained for all eight combinations of inputs, from which biophysical models can extract part activities and the response functions of sensors and gates. Various unexpected failure modes are identified, including cryptic antisense promoters, terminator failure, and a sensor malfunction due to media‐induced changes in host gene expression. This can guide the selection of new parts to fix these problems, which we demonstrate by using a bidirectional terminator to disrupt observed antisense transcription. This work introduces RNA‐seq as a powerful method for circuit characterization and debugging that overcomes the limitations of fluorescent reporters and scales to large systems composed of many parts.
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Affiliation(s)
- Thomas E Gorochowski
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Amin Espah Borujeni
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yongjin Park
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Alec Ak Nielsen
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jing Zhang
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Bryan S Der
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - D Benjamin Gordon
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.,Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Christopher A Voigt
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA .,Broad Institute of MIT and Harvard, Cambridge, MA, USA
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9
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Acevedo A, Conejeros R, Aroca G. Ethanol production improvement driven by genome-scale metabolic modeling and sensitivity analysis in Scheffersomyces stipitis. PLoS One 2017; 12:e0180074. [PMID: 28658270 PMCID: PMC5489217 DOI: 10.1371/journal.pone.0180074] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 06/11/2017] [Indexed: 11/18/2022] Open
Abstract
The yeast Scheffersomyces stipitis naturally produces ethanol from xylose, however reaching high ethanol yields is strongly dependent on aeration conditions. It has been reported that changes in the availability of NAD(H/+) cofactors can improve fermentation in some microorganisms. In this work genome-scale metabolic modeling and phenotypic phase plane analysis were used to characterize metabolic response on a range of uptake rates. Sensitivity analysis was used to assess the effect of ARC on ethanol production indicating that modifying ARC by inhibiting the respiratory chain ethanol production can be improved. It was shown experimentally in batch culture using Rotenone as an inhibitor of the mitochondrial NADH dehydrogenase complex I (CINADH), increasing ethanol yield by 18%. Furthermore, trajectories for uptakes rates, specific productivity and specific growth rate were determined by modeling the batch culture, to calculate ARC associated to the addition of CINADH inhibitor. Results showed that the increment in ethanol production via respiratory inhibition is due to excess in ARC, which generates an increase in ethanol production. Thus ethanol production improvement could be predicted by a change in ARC.
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Affiliation(s)
- Alejandro Acevedo
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Av. Brasil 2085, Valparaíso, Chile
| | - Raúl Conejeros
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Av. Brasil 2085, Valparaíso, Chile
- * E-mail:
| | - Germán Aroca
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Av. Brasil 2085, Valparaíso, Chile
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10
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Gao M, Cao M, Suástegui M, Walker J, Rodriguez Quiroz N, Wu Y, Tribby D, Okerlund A, Stanley L, Shanks JV, Shao Z. Innovating a Nonconventional Yeast Platform for Producing Shikimate as the Building Block of High-Value Aromatics. ACS Synth Biol 2017; 6:29-38. [PMID: 27600996 DOI: 10.1021/acssynbio.6b00132] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The shikimate pathway serves an essential role in many organisms. Not only are the three aromatic amino acids synthesized through this pathway, but many secondary metabolites also derive from it. Decades of effort have been invested into engineering Saccharomyces cerevisiae to produce shikimate and its derivatives. In addition to the ability to express cytochrome P450, S. cerevisiae is generally recognized as safe for producing compounds with nutraceutical and pharmaceutical applications. However, the intrinsically complicated regulations involved in central metabolism and the low precursor availability in S. cerevisiae has limited production levels. Here we report the development of a new platform based on Scheffersomyces stipitis, whose superior xylose utilization efficiency makes it particularly suited to produce the shikimate group of compounds. Shikimate was produced at 3.11 g/L, representing the highest level among shikimate pathway products in yeasts. Our work represents a new exploration toward expanding the current collection of microbial factories.
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Affiliation(s)
- Meirong Gao
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Mingfeng Cao
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Miguel Suástegui
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - James Walker
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Natalia Rodriguez Quiroz
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Yutong Wu
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Dana Tribby
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Adam Okerlund
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Levi Stanley
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Jacqueline V. Shanks
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
| | - Zengyi Shao
- Department of Chemical and Biological
Engineering, ‡NSF Engineering Research Center
for Biorenewable Chemicals (CBiRC), §Department of Chemistry, ∥Interdepartmental Microbiology
Program, Iowa State University, Ames, Iowa 50011, United States
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11
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A Synthetic Hybrid Promoter for Xylose-Regulated Control of Gene Expression in Saccharomyces Yeasts. Mol Biotechnol 2016; 59:24-33. [DOI: 10.1007/s12033-016-9991-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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12
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Xu Q, Liu Y, Li S, Jiang L, Huang H, Wen J. Transcriptome analysis of Rhizopus oryzae in response to xylose during fumaric acid production. Bioprocess Biosyst Eng 2016; 39:1267-80. [DOI: 10.1007/s00449-016-1605-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Accepted: 04/04/2016] [Indexed: 12/20/2022]
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13
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Xylose-induced dynamic effects on metabolism and gene expression in engineered Saccharomyces cerevisiae in anaerobic glucose-xylose cultures. Appl Microbiol Biotechnol 2015; 100:969-85. [DOI: 10.1007/s00253-015-7038-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Revised: 09/14/2015] [Accepted: 09/22/2015] [Indexed: 12/27/2022]
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Liu X, Luo Y, Mohamed OA, Liu D, Wei G. Global transcriptome analysis of Mesorhizobium alhagi CCNWXJ12-2 under salt stress. BMC Microbiol 2014; 14:1. [PMID: 25539655 PMCID: PMC4302635 DOI: 10.1186/s12866-014-0319-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 12/11/2014] [Indexed: 11/24/2022] Open
Abstract
Background Mesorhizobium alhagi CCNWXJ12-2 is a α-proteobacterium which could be able to fix nitrogen in the nodules formed with Alhagi sparsifolia in northwest of China. Desiccation and high salinity are the two major environmental problems faced by M. alhagi CCNWXJ12-2. In order to identify genes involved in salt-stress adaption, a global transcriptional analysis of M. alhagi CCNWXJ12-2 growing under salt-free and high salt conditions was carried out. The next generation sequencing technology, RNA-Seq, was used to obtain the transcription profiles. Results We have compared the transcriptome of M. alhagi growing in TY medium under high salt conditions (0.4 M NaCl) with salt free conditions as a control. A total of 1,849 differentially expressed genes (fold change ≧ 2) were identified and 933 genes were downregulated while 916 genes were upregulated under high salt condition. Except for the upregulation of some genes proven to be involved in salt resistance, we found that the expression levels of protein secretion systems were changed under high salt condition and the expression levels of some heat shock proteins were reduced by salt stress. Notably, a gene encoding YadA domain-containing protein (yadA), a gene encoding trimethylamine methyltransferase (mttB) and a gene encoding formate--tetrahydrofolate ligase (fhs) were highly upregulated. Growth analysis of the three gene knockout mutants under salt stress demonstrated that yadA was involved in salt resistance while the other two were not. Conclusions To our knowledge, this is the first report about transcriptome analysis of a rhizobia using RNA-Seq to elucidate the salt resistance mechanism. Our results showed the complex mechanism of bacterial adaption to salt stress and it was a systematic work for bacteria to cope with the high salinity environmental problems. Therefore, these results could be helpful for further investigation of the bacterial salt resistance mechanism. Electronic supplementary material The online version of this article (doi:10.1186/s12866-014-0319-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | - Gehong Wei
- State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,, College of Life Sciences, Northwest A&F University, Yangling 712100, Shaanxi, China.
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Zhao G, Yao Y, Hou L, Wang C, Cao X. Comparison of the genomes and transcriptomes associated with the different protease secretions of Aspergillus oryzae 100-8 and 3.042. Biotechnol Lett 2014; 36:2053-8. [PMID: 25048221 DOI: 10.1007/s10529-014-1574-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 05/29/2014] [Indexed: 10/25/2022]
Abstract
Aspergillus oryzae is used to produce traditional fermented foods and beverages. A. oryzae 3.042 produces a neutral protease and an alkaline protease but rarely an acid protease, which is unfavourable to soy-sauce fermentation. A. oryzae 100-8 was obtained by N(+) ion implantation mutagenesis of A. oryzae 3.042, and the protease secretions of these two strains are different. Sequencing the genome of A. oryzae 100-8 and comparing it to the genomes of A. oryzae 100-8 and 3.042 revealed some differences, such as single nucleotide polymorphisms, nucleotide deletion or insertion. Some of these differences may reflect the ability of A. oryzae to secrete proteases. Transcriptional sequencing and analysis of the two strains during the same growth processes provided further insights into the genes and pathways involved in protease secretion.
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Affiliation(s)
- Guozhong Zhao
- Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Ministry of Education, Tianjin, 300457, People's Republic of China,
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Li J, Lin L, Li H, Tian C, Ma Y. Transcriptional comparison of the filamentous fungus Neurospora crassa growing on three major monosaccharides D-glucose, D-xylose and L-arabinose. BIOTECHNOLOGY FOR BIOFUELS 2014; 7:31. [PMID: 24581151 PMCID: PMC4015282 DOI: 10.1186/1754-6834-7-31] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 02/14/2014] [Indexed: 05/09/2023]
Abstract
BACKGROUND D-glucose, D-xylose and L-arabinose are the three major monosaccharides in plant cell walls. Complete utilization of all three sugars is still a bottleneck for second-generation cellulolytic bioethanol production, especially for L-arabinose. However, little is known about gene expression profiles during L-arabinose utilization in fungi and a comparison of the genome-wide fungal response to these three major monosaccharides has not yet been reported. RESULTS Using next-generation sequencing technology, we have analyzed the transcriptome of N. crassa grown on L-arabinose versus D-xylose, with D-glucose as the reference. We found that the gene expression profiles on L-arabinose were dramatically different from those on D-xylose. It appears that L-arabinose can rewire the fungal cell metabolic pathway widely and provoke the expression of many kinds of sugar transporters, hemicellulase genes and transcription factors. In contrast, many fewer genes, mainly related to the pentose metabolic pathway, were upregulated on D-xylose. The rewired metabolic response to L-arabinose was significantly different and wider than that under no carbon conditions, although the carbon starvation response was initiated on L-arabinose. Three novel sugar transporters were identified and characterized for their substrates here, including one glucose transporter GLT-1 (NCU01633) and two novel pentose transporters, XAT-1 (NCU01132), XYT-1 (NCU05627). One transcription factor associated with the regulation of hemicellulase genes, HCR-1 (NCU05064) was also characterized in the present study. CONCLUSIONS We conducted the first transcriptome analysis of Neurospora crassa grown on L-arabinose and performed a comparative analysis with cells grown on D-xylose and D-glucose, which deepens the understanding of the utilization of L-arabinose and D-xylose in filamentous fungi. The dataset generated by this research will be useful for mining target genes for D-xylose and L-arabinose utilization engineering and the novel sugar transportes identified are good targets for pentose untilization and biofuels production. Moreover, hemicellulase production by fungi could be improved by modifying the hemicellulase regulator discovered here.
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Affiliation(s)
- Jingen Li
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Liangcai Lin
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
| | - Huiyan Li
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
| | - Chaoguang Tian
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
| | - Yanhe Ma
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
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Differential gene expression in Pycnoporus coccineus during interspecific mycelial interactions with different competitors. Appl Environ Microbiol 2013; 79:6626-36. [PMID: 23974131 DOI: 10.1128/aem.02316-13] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Fungi compete against each other for environmental resources. These interspecific combative interactions encompass a wide range of mechanisms. In this study, we highlight the ability of the white-rot fungus Pycnoporus coccineus to quickly overgrow or replace a wide range of competitor fungi, including the gray-mold fungus Botrytis cinerea and the brown-rot fungus Coniophora puteana. To gain a better understanding of the mechanisms deployed by P. coccineus to compete against other fungi and to assess whether common pathways are used to interact with different competitors, differential gene expression in P. coccineus during cocultivation was assessed by transcriptome sequencing and confirmed by quantitative reverse transcription-PCR analysis of a set of 15 representative genes. Compared with the pure culture, 1,343 transcripts were differentially expressed in the interaction with C. puteana and 4,253 were differentially expressed in the interaction with B. cinerea, but only 197 transcripts were overexpressed in both interactions. Overall, the results suggest that a broad array of functions is necessary for P. coccineus to replace its competitors and that different responses are elicited by the two competitors, although a portion of the mechanism is common to both. However, the functions elicited by the expression of specific transcripts appear to converge toward a limited set of roles, including detoxification of secondary metabolites.
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Comparative RNA-sequencing of the acarbose producer Actinoplanes sp. SE50/110 cultivated in different growth media. J Biotechnol 2013; 167:166-77. [DOI: 10.1016/j.jbiotec.2012.10.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2012] [Revised: 09/18/2012] [Accepted: 10/28/2012] [Indexed: 12/14/2022]
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Caspeta L, Nielsen J. Toward systems metabolic engineering ofAspergillusandPichiaspecies for the production of chemicals and biofuels. Biotechnol J 2013; 8:534-44. [DOI: 10.1002/biot.201200345] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 02/19/2013] [Accepted: 03/14/2013] [Indexed: 12/11/2022]
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Chung BKS, Lakshmanan M, Klement M, Ching CB, Lee DY. Metabolic reconstruction and flux analysis of industrial Pichia yeasts. Appl Microbiol Biotechnol 2013; 97:1865-73. [PMID: 23339015 DOI: 10.1007/s00253-013-4702-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 01/03/2013] [Accepted: 01/07/2013] [Indexed: 12/24/2022]
Abstract
Pichia yeasts have been recognized as important microbial cell factories in the biotechnological industry. Notably, the Pichia pastoris and Pichia stipitis species have attracted much research interest due to their unique cellular physiology and metabolic capability: P. pastoris has the ability to utilize methanol for cell growth and recombinant protein production, while P. stipitis is capable of assimilating xylose to produce ethanol under oxygen-limited conditions. To harness these characteristics for biotechnological applications, it is highly required to characterize their metabolic behavior. Recently, following the genome sequencing of these two Pichia species, genome-scale metabolic networks have been reconstructed to model the yeasts' metabolism from a systems perspective. To date, there are three genome-scale models available for each of P. pastoris and P. stipitis. In this mini-review, we provide an overview of the models, discuss certain limitations of previous studies, and propose potential future works that can be conducted to better understand and engineer Pichia yeasts for industrial applications.
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Affiliation(s)
- Bevan Kai-Sheng Chung
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, #06-01, Centros, Singapore 138668, Singapore
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Papini M, Nookaew I, Uhlén M, Nielsen J. Scheffersomyces stipitis: a comparative systems biology study with the Crabtree positive yeast Saccharomyces cerevisiae. Microb Cell Fact 2012; 11:136. [PMID: 23043429 PMCID: PMC3528450 DOI: 10.1186/1475-2859-11-136] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Accepted: 09/13/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Scheffersomyces stipitis is a Crabtree negative yeast, commonly known for its capacity to ferment pentose sugars. Differently from Crabtree positive yeasts such as Saccharomyces cerevisiae, the onset of fermentation in S. stipitis is not dependent on the sugar concentration, but is regulated by a decrease in oxygen levels. Even though S. stipitis has been extensively studied due to its potential application in pentoses fermentation, a limited amount of information is available about its metabolism during aerobic growth on glucose. Here, we provide a systems biology based comparison between the two yeasts, uncovering the metabolism of S. stipitis during aerobic growth on glucose under batch and chemostat cultivations. RESULTS Starting from the analysis of physiological data, we confirmed through 13C-based flux analysis the fully respiratory metabolism of S. stipitis when growing both under glucose limited or glucose excess conditions. The patterns observed showed similarity to the fully respiratory metabolism observed for S. cerevisiae under chemostat cultivations however, intracellular metabolome analysis uncovered the presence of several differences in metabolite patterns. To describe gene expression levels under the two conditions, we performed RNA sequencing and the results were used to quantify transcript abundances of genes from the central carbon metabolism and compared with those obtained with S. cerevisiae. Interestingly, genes involved in central pathways showed different patterns of expression, suggesting different regulatory networks between the two yeasts. Efforts were focused on identifying shared and unique families of transcription factors between the two yeasts through in silico transcription factors analysis, suggesting a different regulation of glycolytic and glucoenogenic pathways. CONCLUSIONS The work presented addresses the impact of high-throughput methods in describing and comparing the physiology of Crabtree positive and Crabtree negative yeasts. Based on physiological data and flux analysis we identified the presence of one metabolic condition for S. stipitis under aerobic batch and chemostat cultivations, which shows similarities to the oxidative metabolism observed for S. cerevisiae under chemostat cultivations. Through metabolome analysis and genome-wide transcriptomic analysis several differences were identified. Interestingly, in silico analysis of transciption factors was useful to address a different regulation of mRNAs of genes involved in the central carbon metabolism. To our knowledge, this is the first time that the metabolism of S. stiptis is investigated in details and is compared to S. cerevisiae. Our study provides useful results and allows for the possibility to incorporate these data into recently developed genome-scaled metabolic, thus contributing to improve future industrial applications of S. stipitis as cell factory.
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Affiliation(s)
- Marta Papini
- Novo Nordisk Foundation Center for Biosustainability, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg, SE, 412 96, Sweden
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Liu T, Zou W, Liu L, Chen J. A constraint-based model of Scheffersomyces stipitis for improved ethanol production. BIOTECHNOLOGY FOR BIOFUELS 2012; 5:72. [PMID: 22998943 PMCID: PMC3503688 DOI: 10.1186/1754-6834-5-72] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 09/13/2012] [Indexed: 05/28/2023]
Abstract
UNLABELLED BACKGROUND As one of the best xylose utilization microorganisms, Scheffersomyces stipitis exhibits great potential for the efficient lignocellulosic biomass fermentation. Therefore, a comprehensive understanding of its unique physiological and metabolic characteristics is required to further improve its performance on cellulosic ethanol production. RESULTS A constraint-based genome-scale metabolic model for S. stipitis CBS 6054 was developed on the basis of its genomic, transcriptomic and literature information. The model iTL885 consists of 885 genes, 870 metabolites, and 1240 reactions. During the reconstruction process, 36 putative sugar transporters were reannotated and the metabolisms of 7 sugars were illuminated. Essentiality study was conducted to predict essential genes on different growth media. Key factors affecting cell growth and ethanol formation were investigated by the use of constraint-based analysis. Furthermore, the uptake systems and metabolic routes of xylose were elucidated, and the optimization strategies for the overproduction of ethanol were proposed from both genetic and environmental perspectives. CONCLUSIONS Systems biology modelling has proven to be a powerful tool for targeting metabolic changes. Thus, this systematic investigation of the metabolism of S. stipitis could be used as a starting point for future experiment designs aimed at identifying the metabolic bottlenecks of this important yeast.
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Affiliation(s)
- Ting Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, China
| | - Wei Zou
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, China
| | - Liming Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, China
| | - Jian Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu, 214122, China
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Caspeta L, Shoaie S, Agren R, Nookaew I, Nielsen J. Genome-scale metabolic reconstructions of Pichia stipitis and Pichia pastoris and in silico evaluation of their potentials. BMC SYSTEMS BIOLOGY 2012; 6:24. [PMID: 22472172 PMCID: PMC3364918 DOI: 10.1186/1752-0509-6-24] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 04/04/2012] [Indexed: 11/18/2022]
Abstract
Background Pichia stipitis and Pichia pastoris have long been investigated due to their native abilities to metabolize every sugar from lignocellulose and to modulate methanol consumption, respectively. The latter has been driving the production of several recombinant proteins. As a result, significant advances in their biochemical knowledge, as well as in genetic engineering and fermentation methods have been generated. The release of their genome sequences has allowed systems level research. Results In this work, genome-scale metabolic models (GEMs) of P. stipitis (iSS884) and P. pastoris (iLC915) were reconstructed. iSS884 includes 1332 reactions, 922 metabolites, and 4 compartments. iLC915 contains 1423 reactions, 899 metabolites, and 7 compartments. Compared with the previous GEMs of P. pastoris, PpaMBEL1254 and iPP668, iLC915 contains more genes and metabolic functions, as well as improved predictive capabilities. Simulations of physiological responses for the growth of both yeasts on selected carbon sources using iSS884 and iLC915 closely reproduced the experimental data. Additionally, the iSS884 model was used to predict ethanol production from xylose at different oxygen uptake rates. Simulations with iLC915 closely reproduced the effect of oxygen uptake rate on physiological states of P. pastoris expressing a recombinant protein. The potential of P. stipitis for the conversion of xylose and glucose into ethanol using reactors in series, and of P. pastoris to produce recombinant proteins using mixtures of methanol and glycerol or sorbitol are also discussed. Conclusions In conclusion the first GEM of P. stipitis (iSS884) was reconstructed and validated. The expanded version of the P. pastoris GEM, iLC915, is more complete and has improved capabilities over the existing models. Both GEMs are useful frameworks to explore the versatility of these yeasts and to capitalize on their biotechnological potentials.
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Affiliation(s)
- Luis Caspeta
- Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
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