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Teles GH, Xavier MR, Da Silva JM, De Souza RB, de Barros Pita W, de Morais MA. The Metabolism of Respiring Carbon Sources by Dekkera bruxellensis and Its Relation with the Production of Acetate. Appl Biochem Biotechnol 2023; 195:6369-6391. [PMID: 36867386 DOI: 10.1007/s12010-023-04398-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/17/2023] [Indexed: 03/04/2023]
Abstract
Dekkera bruxellensis has been studied for several aspects of its metabolism over the past years, which has expanded our comprehension on its importance to industrial fermentation processes and uncovered its industrial relevance. Acetate is a metabolite often found in D. bruxellensis aerobic cultivations, whereas its production is linked to decreased ethanol yields. In a previous work, we aimed to understand how acetate metabolism affected the fermentation capacity of D. bruxellensis. In the present work, we evaluated the role of acetate metabolism in respiring cells using ammonium or nitrate as nitrogen sources. Our results showed that galactose is a strictly respiratory sugar and that a relevant part of its carbon is lost, while the remaining is metabolised through the Pdh bypass pathway before being assimilated into biomass. When this pathway was blocked, yeast growth was reduced while more carbon was assimilated to the biomass. In nitrate, more acetate was produced as expected, which increased carbon assimilation, although less galactose was uptaken from the medium. This scenario was not affected by the Pdh bypass inhibition. The confirmation that acetate production was crucial for carbon assimilation was brought by cultivations in pyruvate. All physiological data were connected to the expression patterns of PFK1, PDC1, ADH1, ALD3, ALD5 and ATP1 genes. Other respiring carbon sources could only be properly used by the cells when some external acetate was supplied. Therefore, the results reported herein helped in providing valuable contributions to the understanding of the oxidative metabolism in this potential industrial yeast.
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Affiliation(s)
- Gilberto Henrique Teles
- Laboratory of Microbial Genetics, Department of Genetics, Federal University of Pernambuco, Av. Moraes Rego, 1235. Cidade Universitária, Recife, PE, 50.670-901, Brazil
| | - Mariana Rodrigues Xavier
- Laboratory of Microbial Genetics, Department of Genetics, Federal University of Pernambuco, Av. Moraes Rego, 1235. Cidade Universitária, Recife, PE, 50.670-901, Brazil
| | | | - Rafael Barros De Souza
- Laboratory of Microbial Metabolism, Institute of Biological Sciences, University of Pernambuco, Recife, Brazil
| | | | - Marcos Antonio de Morais
- Laboratory of Microbial Genetics, Department of Genetics, Federal University of Pernambuco, Av. Moraes Rego, 1235. Cidade Universitária, Recife, PE, 50.670-901, Brazil.
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Tang H, Chen Z, Shao Y, Ju X, Li L. Development of an enzymatic cascade to systematically utilize lignocellulosic monosaccharide. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2023; 103:1974-1980. [PMID: 36448581 DOI: 10.1002/jsfa.12364] [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: 10/04/2022] [Revised: 11/23/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND The fermentation valorization of two main lignocellulosic monosaccharides, glucose and xylose, is extensively developed; however, it is restricted by limited yield and process complexity. An in vitro enzymatic cascade reaction can be an alternative approach. RESULTS In this study, a three-stage, five-enzyme cascade was developed to convert pretreated biomass to valuable chemicals. First, a ribose-5-phosphate isomerase B mutant isomerized xylose to d-xylulose with high substrate specificity, and a d-arabinose dehydrogenase continued to reduce d-xylulose to d-arabitol. Simultaneously, glucose was utilized for the coenzyme regeneration catalyzed by a glucose dehydrogenase, generating useful gluconic acid and achieving 73% of total conversion rate after 36 h. Then, six kinds of pretreated biomass lignocellulose were hydrolyzed by cellulase and hemicellulase, and corn cob was identified as the initial substrate for providing the highest monosaccharide content. A 65% conversion rate of the lignocellulosic xylose was obtained after 24 h. CONCLUSIONS This study presents a proof of concept to convert main lignocellulosic monosaccharides systematically by an enzymatic cascade at stoichiometric ratio. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Hengtao Tang
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, P. R. China
| | - Zhi Chen
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, P. R. China
| | - Yu Shao
- Engineering and Technology Centers of Transdermal Drug Delivery System of Jiangsu Province, Yunnan Baiyao Group Wuxi Pharmaceutical Co., Ltd, Wuxi, P. R. China
| | - Xin Ju
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, P. R. China
| | - Liangzhi Li
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, P. R. China
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3
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Tang H, Zhou Z, Chen Z, Ju X, Li L. Development of a sugar isomerase cascade to convert D-xylose to rare sugars. MOLECULAR CATALYSIS 2022. [DOI: 10.1016/j.mcat.2022.112672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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A High-Throughput Absolute Abundance Quantification Method for the Characterisation of Daqu Core Fungal Communities. FERMENTATION-BASEL 2022. [DOI: 10.3390/fermentation8080345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
An inherent issue in high-throughput sequencing applications is that they provide compositional data for relative abundance. This often obscures the true biomass and potential functions of fungi in the community. Therefore, we presented a high-throughput absolute quantification (HAQ) method to quantitatively estimate the fungal abundance in Daqu. In this study, five internal standard plasmids (ISPs) were designed for the fungal ITS2 subregion with high length variations. Five ISPs were then utilised to establish standard curves with a quantitative concentration range of 103–107 cells/g, and this was used to quantify the core fungi, including Basidiomycota, Ascomycota, and Mucoromycota. Using three types of mature Daqu from different regions, we demonstrated that the HAQ method yielded community profiles substantially different from those derived using relative abundances. Then, the HAQ method was applied to the Daqu during fermentation. The initial formation of the Daqu surface occurred in the fourth stage, which was mainly driven by moisture. The key fungi that caused the initial formation of the Daqu surface included Hyphopichia burtonii, Saccharomycopsis fibuligera, and Pichia kudriavzevii. The initial formation of the Daqu core occurred in the fifth stage, which was mainly affected by moisture and reducing the sugar content. The key fungi that cause the initial formation of the Daqu core included S. fibuligera and Paecilomyces verrucosus. We conclude that the HAQ method, when applied to ITS2 gene fungal community profiling, is quantitative and that its use will greatly improve our understanding of the fungal ecosystem in Daqu.
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Teles GH, da Silva JM, Xavier MR, de Souza RB, de Barros Pita W, de Morais Junior MA. Metabolic and biotechnological insights on the analysis of the Pdh bypass and acetate production in the yeast Dekkera bruxellensis. J Biotechnol 2022; 355:42-52. [PMID: 35760147 DOI: 10.1016/j.jbiotec.2022.06.008] [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: 03/27/2022] [Revised: 06/01/2022] [Accepted: 06/21/2022] [Indexed: 11/29/2022]
Abstract
The advancement of knowledge about the physiology of Dekkera bruxellensis has shown its potential for the production of fuel ethanol very close to the conventional fermenting yeast S. cerevisiae. However, some aspects of its metabolism remain uncovered. In the present study, the respiro-fermentative parameters of D. bruxellensis GDB 248 were evaluated under different cultivation conditions. The results showed that sucrose was more efficiently converted to ethanol than glucose, regardless the nitrogen source, which points out for the industrial efficiency of this yeast in sucrose-based substrate. The blockage of the cytosolic acetate production incremented the yeast fermentative efficiency by 27% (in glucose) and 14% (in sucrose). On the other hand, the presence of nitrate as inducer of acetate production reducing the production of ethanol. Altogether, these results settled the hypothesis that acetate metabolism is the main constraint for ethanol production. Besides, this acetate-generating pathway seems to exert some regulatory action on the flux and distribution of the carbon flowing throught the central metabolism. These physiological aspects were corroborated by the relative expression analysis of key genes in the crossroad to ethanol, acetate and biomass formation. All the results were discussed in the light of the industrial potential of this yeast.
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Affiliation(s)
- Gilberto Henrique Teles
- Laboratory of Microbial Genetics, Department of Genetics, Federal University of Pernambuco, Recife, Brazil
| | - Jackeline Maria da Silva
- Laboratory of Molecular Genetics, Department of Antibiotics, Federal University of Pernambuco, Recife, Brazil
| | - Mariana Rodrigues Xavier
- Laboratory of Microbial Genetics, Department of Genetics, Federal University of Pernambuco, Recife, Brazil
| | - Rafael Barros de Souza
- Laboratory of Microbial Metabolism, Institute of Biological Sciences, University of Pernambuco, Recife, Brazil
| | - Will de Barros Pita
- Laboratory of Molecular Genetics, Department of Antibiotics, Federal University of Pernambuco, Recife, Brazil
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Wang X, Luo X. Precursor Quantitation Methods for Next Generation Food Production. Front Bioeng Biotechnol 2022; 10:849177. [PMID: 35360389 PMCID: PMC8960114 DOI: 10.3389/fbioe.2022.849177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 02/22/2022] [Indexed: 11/21/2022] Open
Abstract
Food is essential for human survival. Nowadays, traditional agriculture faces challenges in balancing the need of sustainable environmental development and the rising food demand caused by an increasing population. In addition, in the emerging of consumers' awareness of health related issues bring a growing trend towards novel nature-based food additives. Synthetic biology, using engineered microbial cell factories for production of various molecules, shows great advantages for generating food alternatives and additives, which not only relieve the pressure laid on tradition agriculture, but also create a new stage in healthy and sustainable food supplement. The biosynthesis of food components (protein, fats, carbohydrates or vitamins) in engineered microbial cells often involves cellular central metabolic pathways, where common precursors are processed into different proteins and products. Quantitation of the precursors provides information of the metabolic flux and intracellular metabolic state, giving guidance for precise pathway engineering. In this review, we summarized the quantitation methods for most cellular biosynthetic precursors, including energy molecules and co-factors involved in redox-reactions. It will also be useful for studies worked on pathway engineering of other microbial-derived metabolites. Finally, advantages and limitations of each method are discussed.
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Affiliation(s)
- Xinran Wang
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Xiaozhou Luo
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
- Shenzhen Institute of Advanced Technology, Shenzhen, China
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State-of-the-art in analytical methods for metabolic profiling of Saccharomyces cerevisiae. Microchem J 2021. [DOI: 10.1016/j.microc.2021.106704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Wang R, Xu X, Yao X, Tang H, Ju X, Li L. Enhanced isomerization of rare sugars by ribose-5-phosphate isomerase A from Ochrobactrum sp. CSL1. Enzyme Microb Technol 2021; 148:109789. [PMID: 34116752 DOI: 10.1016/j.enzmictec.2021.109789] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 03/19/2021] [Accepted: 03/22/2021] [Indexed: 11/19/2022]
Abstract
Ribose-5-phosphate isomerase A (RpiA) is of great importance in biochemistry research, however its application in biotechnology has not been fully explored. In this study the activity of RpiA from Ochrobactrum sp. CSL1 (OsRpiA) towards D-allose was engineered based on sequential and structural analyses. Strategies of alanine scanning, rational design and saturated mutagenesis were employed to create three mutant libraries. A single mutant of K124A showed a 45 % activity improvement towards D-allose. The reaction properties of the mutant were analyzed, and a shift of optimal pH and higher thermal stability at low reaction temperatures were identified. The conversion of D-allose was also improved by 40 % using K124A, and higher activities on major substrates were found in the mutant's substrate scope, implying its application potential in rare sugar preparation. Kinetics analysis revealed that Km of K124A mutant decreased by 12 % and the catalytic efficiency increased by 65 % towards D-allose. Moreover, molecular dynamics simulation illustrated the binding of substrate and K124A was more stable than that of the wild-type. The shorter distance and more relax bond angle between the catalytic residue of K124A and D-allose explained the activity improvement in detail. This study highlights the potential of OsRpiA as a biocatalyst for rare sugar preparation, and provides distinct evidences for its catalytic mechanism.
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Affiliation(s)
- Rong Wang
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, PR China
| | - Xinqi Xu
- Fujian Key Laboratory of Marine Enzyme Engineering, College of Biosciences and Engineering, Fuzhou University, Fuzhou, 350116, PR China
| | - Xuemei Yao
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, PR China
| | - Hengtao Tang
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, PR China
| | - Xin Ju
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, PR China.
| | - Liangzhi Li
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, PR China.
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9
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Kumar K, Venkatraman V, Bruheim P. Adaptation of central metabolite pools to variations in growth rate and cultivation conditions in Saccharomyces cerevisiae. Microb Cell Fact 2021; 20:64. [PMID: 33750414 PMCID: PMC7941957 DOI: 10.1186/s12934-021-01557-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 03/01/2021] [Indexed: 11/19/2022] Open
Abstract
Background Saccharomyces cerevisiae is a well-known popular model system for basic biological studies and serves as a host organism for the heterologous production of commercially interesting small molecules and proteins. The central metabolism is at the core to provide building blocks and energy to support growth and survival in normal situations as well as during exogenous stresses and forced heterologous protein production. Here, we present a comprehensive study of intracellular central metabolite pool profiling when growing S. cerevisiae on different carbon sources in batch cultivations and at different growth rates in nutrient-limited glucose chemostats. The latest versions of absolute quantitative mass spectrometry-based metabolite profiling methodology were applied to cover glycolytic and pentose phosphate pathway metabolites, tricarboxylic acid cycle (TCA), complete amino acid, and deoxy-/nucleoside phosphate pools. Results Glutamate, glutamine, alanine, and citrate were the four most abundant metabolites for most conditions tested. The amino acid is the dominant metabolite class even though a marked relative reduction compared to the other metabolite classes was observed for nitrogen and phosphate limited chemostats. Interestingly, glycolytic and pentose phosphate pathway (PPP) metabolites display the largest variation among the cultivation conditions while the nucleoside phosphate pools are more stable and vary within a closer concentration window. The overall trends for glucose and nitrogen-limited chemostats were increased metabolite pools with the increasing growth rate. Next, comparing the chosen chemostat reference growth rate (0.12 h−1, approximate one-fourth of maximal unlimited growth rate) illuminates an interesting pattern: almost all pools are lower in nitrogen and phosphate limited conditions compared to glucose limitation, except for the TCA metabolites citrate, isocitrate and α-ketoglutarate. Conclusions This study provides new knowledge-how the central metabolism is adapting to various cultivations conditions and growth rates which is essential for expanding our understanding of cellular metabolism and the development of improved phenotypes in metabolic engineering. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-021-01557-8.
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Affiliation(s)
- Kanhaiya Kumar
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Vishwesh Venkatraman
- Department of Chemistry, Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Per Bruheim
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway.
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Deschoenmaeker F, Mihara S, Niwa T, Taguchi H, Wakabayashi KI, Toyoshima M, Shimizu H, Hisabori T. Thioredoxin pathway in anabaena sp. PCC 7120: activity of NADPH-thioredoxin reductase C. J Biochem 2021; 169:709-719. [PMID: 33537746 DOI: 10.1093/jb/mvab014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 01/28/2021] [Indexed: 11/13/2022] Open
Abstract
To understand the physiological role of NADPH-thioredoxin reductase C (NTRC) in cyanobacteria, we investigated an NTRC-deficient mutant strain of Anabaena sp., PCC 7120, cultivated under different regimes of nitrogen supplementation and light exposure. The deletion of ntrC did not induce a change in the cell structure and metabolic pathways. However, time-dependent changes in the abundance of specific proteins and metabolites were observed. A decrease in chlorophyll a was correlated with a decrease in chlorophyll a biosynthesis enzymes and PSI subunits. The deletion of ntrC led to a deregulation of nitrogen metabolism, including the NtcA accumulation and heterocyst-specific proteins while nitrate ions were available in the culture medium. Interestingly, this deletion resulted in a redox imbalance, indicated by higher peroxide levels, higher catalase activity, and the induction of chaperones such as MsrA. Surprisingly, the antioxidant protein 2-Cys Prx was down-regulated. The deficiency in ntrC also resulted in the accumulation of metabolites such as 6-phosphogluconate, ADP, and ATP. Higher levels of NADP+ and NADPH partly correlated with higher G6PDH activity. Rather than impacting protein expression levels, NTRC appears to be involved in the direct regulation of enzymes, especially during the dark to light transition period.
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Affiliation(s)
- Frédéric Deschoenmaeker
- Laboratory for Chemistry and Life Science, Institute for Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan
| | - Shoko Mihara
- Laboratory for Chemistry and Life Science, Institute for Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan.,Department of Life Science, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama 226-8501, Japan
| | - Tatsuya Niwa
- Cell Biology Center, Institute for Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-S2-19, Midori-ku, Yokohama, 226-8503 Japan
| | - Hideki Taguchi
- Cell Biology Center, Institute for Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-S2-19, Midori-ku, Yokohama, 226-8503 Japan
| | - Ken-Ichi Wakabayashi
- Laboratory for Chemistry and Life Science, Institute for Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan.,Department of Life Science, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama 226-8501, Japan
| | - Masakazu Toyoshima
- Department of Bioinformatic Engeneering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Hiroshi Shimizu
- Department of Bioinformatic Engeneering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Toru Hisabori
- Laboratory for Chemistry and Life Science, Institute for Innovative Research, Tokyo Institute of Technology, Nagatsuta 4259-R1-8, Midori-ku, Yokohama, 226-8503, Japan.,Department of Life Science, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama 226-8501, Japan
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Tang H, Ju X, Zhao J, Li L. Engineering ribose-5-phosphate isomerase B from a central carbon metabolic enzyme to a promising sugar biocatalyst. Appl Microbiol Biotechnol 2021; 105:509-523. [PMID: 33394147 DOI: 10.1007/s00253-020-11075-z] [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: 10/07/2020] [Revised: 12/12/2020] [Accepted: 12/23/2020] [Indexed: 10/22/2022]
Abstract
Ribose-5-phosphate isomerase B (RpiB) was first identified in the pentose phosphate pathway responsible for the inter-conversion of ribose-5-phosphate and ribulose-5-phosphate. Though there are seldom key enzymes in central carbon metabolic system developed as useful biocatalysts, RpiB with the advantages of wide substrate scope and high stereoselectivity has become a potential biotechnological tool to fulfill the demand of rare sugars currently. In this review, the pivotal roles of RpiB in carbon metabolism are summarized, and their sequence identity and structural similarity are discussed. Substrate binding and catalytic mechanisms are illustrated to provide solid foundations for enzyme engineering. Interesting differences in origin, physiological function, structure, and catalytic mechanism between RpiB and ribose-5-phosphate isomerase A are introduced. Moreover, enzyme engineering efforts for rare sugar production are stressed, and prospects of future development are concluded briefly in the viewpoint of biocatalysis. Aided by the progresses of structural and computational biology, the application of RpiB will be promoted greatly in the preparation of valuable molecules. KEY POINTS: • Detailed illustration of RpiB's vital function in central carbon metabolism. • Potential of RpiB in sequence, substrate scope, and mechanism for application. • Enzyme engineering efforts to promote RpiB in the preparation of rare sugars.
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Affiliation(s)
- Hengtao Tang
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No.99 Xuefu Rd., Huqiu district, Suzhou, 215009, Jiangsu Province, People's Republic of China
| | - Xin Ju
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No.99 Xuefu Rd., Huqiu district, Suzhou, 215009, Jiangsu Province, People's Republic of China
| | - Jing Zhao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, People's Republic of China
| | - Liangzhi Li
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, No.99 Xuefu Rd., Huqiu district, Suzhou, 215009, Jiangsu Province, People's Republic of China.
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Novel allosteric inhibition of phosphoribulokinase identified by ensemble kinetic modeling of Synechocystis sp. PCC 6803 metabolism. Metab Eng Commun 2020; 11:e00153. [PMID: 33312875 PMCID: PMC7721636 DOI: 10.1016/j.mec.2020.e00153] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 10/17/2020] [Accepted: 11/17/2020] [Indexed: 12/11/2022] Open
Abstract
The present study attempted a computer simulation of the metabolism of a model cyanobacteria, Synechocystis sp. PCC 6803 (PCC 6803) to predict allosteric inhibitions that are likely to occur in photoautotrophic and mixotrophic conditions as well as in a metabolically engineered strain. PCC 6803 is a promising host for direct biochemical production from CO2; however, further investigation of allosteric regulation is required for rational metabolic engineering to produce target compounds. Herein, ensemble modeling of microbial metabolism was applied to build accurate predictive models by synthesizing the results of multiple models with different parameter sets into a single score to identify plausible allosteric inhibitions. The data driven-computer simulation using metabolic flux, enzyme abundance, and metabolite concentration data successfully identified candidates for allosteric inhibition. The enzyme assay experiment using the recombinant protein confirmed isocitrate was a non-competitive inhibitor of phosphoribulokinase as a novel allosteric regulation of cyanobacteria metabolism.
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Kitamura S, Shimizu H, Toya Y. Identification of a rate-limiting step in a metabolic pathway using the kinetic model and in vitro experiment. J Biosci Bioeng 2020; 131:271-276. [PMID: 33168471 DOI: 10.1016/j.jbiosc.2020.10.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/19/2020] [Accepted: 10/22/2020] [Indexed: 11/16/2022]
Abstract
Identification of the rate-limiting step in a metabolic pathway is an important challenge in metabolic engineering for enhancing pathway flow. Although specific enzyme activities (Vmax) provide valuable clues for the identification, it is time-consuming and difficult to measure multiple enzymes in the pathway because different assay protocols are required for each enzyme. In the present study, we propose a method to simultaneously determine the Vmax values of multiple enzymes using a kinetic model with a time course of the intermediate concentrations through an in vitro experiment. To demonstrate this method, nine glycolysis reactions for converting glucose-6-phosphate (G6P) to pyruvate in Escherichia coli were considered. In a reaction mixture containing G6P and cofactors, glycolysis was initiated by adding a crude cell extract obtained from stationary phase cells. The Vmax values were optimized to minimize the difference between the measured and simulated time-courses using a kinetic model. Metabolic control analysis using the kinetic model with the estimated Vmax values revealed that fructose bisphosphate aldolase (FBA) was the rate-limiting step in the upper part of glycolysis. The addition of FBA in the reaction mixture successfully increased the glycolytic flux in vitro. Furthermore, in vivo, the specific glucose consumption rate of an FBA overexpression strain was 1.4 times higher than that of the control strain during the stationary phase. These results confirmed that FBA was the rate-limiting step in glycolysis under the stationary phase. This approach provides Vmax values of multiple enzymes in a pathway for metabolic control analysis with a kinetic model.
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Affiliation(s)
- Sayaka Kitamura
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Hiroshi Shimizu
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yoshihiro Toya
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
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Absolute Quantification of the Central Carbon Metabolome in Eight Commonly Applied Prokaryotic and Eukaryotic Model Systems. Metabolites 2020; 10:metabo10020074. [PMID: 32093075 PMCID: PMC7073941 DOI: 10.3390/metabo10020074] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 02/14/2020] [Accepted: 02/17/2020] [Indexed: 02/07/2023] Open
Abstract
Absolute quantification of intracellular metabolite pools is a prerequisite for modeling and in-depth biological interpretation of metabolomics data. It is the final step of an elaborate metabolomics workflow, with challenges associated with all steps—from sampling to quantifying the physicochemically diverse metabolite pool. Chromatographic separation combined with mass spectrometric (MS) detection is the superior platform for high coverage, selective, and sensitive detection of metabolites. Herein, we apply our quantitative MS-metabolomics workflow to measure and present the central carbon metabolome of a panel of commonly applied biological model systems. The workflow includes three chromatographic methods combined with isotope dilution tandem mass spectrometry to allow for absolute quantification of 68 metabolites of glycolysis, the pentose phosphate pathway, the tricarboxylic acid cycle, and the amino acid and (deoxy) nucleoside pools. The biological model systems; Bacillus subtilis, Saccharomyces cerevisiae, two microalgal species, and four human cell lines were all cultured in commonly applied culture media and sampled in exponential growth phase. Both literature and databases are scarce with comprehensive metabolite datasets, and existing entries range over several orders of magnitude. The workflow and metabolite panel presented herein can be employed to expand the list of reference metabolomes, as encouraged by the metabolomics community, in a continued effort to develop and refine high-quality quantitative metabolomics workflows.
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Okahashi N, Kawana S, Iida J, Shimizu H, Matsuda F. Fragmentation of Dicarboxylic and Tricarboxylic Acids in the Krebs Cycle Using GC-EI-MS and GC-EI-MS/MS. ACTA ACUST UNITED AC 2020; 8:A0073. [PMID: 32010541 PMCID: PMC6920549 DOI: 10.5702/massspectrometry.a0073] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 07/15/2019] [Indexed: 12/22/2022]
Abstract
Isotope labeling measurements using mass spectrometry can provide informative insights on the metabolic systems of various organisms. The detailed identification of carbon positions included in the fragment ions of dicarboxylic and tricarboxylic acids in central carbon metabolism is needed for precise interpretation of the metabolic states. In this study, fragment ions containing the carbon backbone cleavage of dicarboxylic and tricarboxylic in the Krebs cycle were investigated by using gas chromatography (GC)-electron ionization (EI)-MS and GC-EI-MS/MS. The positions of decarboxylation in the dicarboxylic and tricarboxylic acids were successfully identified by analyses using position-specific 13C-labeled standards prepared by in vitro enzymatic reactions. For example, carboxyl groups of C1 and C6 of trimethylsilyl (TMS)- and tert-butyldimethylsilyl (TBDMS)-derivatized malic and citric acids were primarily cleaved by EI. MS/MS analyses were also performed, and fragment ions of TBDMS-citric and α-ketoglutaric acids (αKG) with the loss of two carboxyl groups in collision-induced dissociation (CID) were observed.
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Affiliation(s)
- Nobuyuki Okahashi
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka, Japan
| | - Shuichi Kawana
- Analytical and Measuring Instruments Division, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, Japan
| | - Junko Iida
- Analytical and Measuring Instruments Division, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, Japan.,Osaka University Shimadzu Analytical Innovation Research Laboratory, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka, Japan
| | - Hiroshi Shimizu
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka, Japan
| | - Fumio Matsuda
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka, Japan
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Maruyama M, Nishiguchi H, Toyoshima M, Okahashi N, Matsuda F, Shimizu H. Time-resolved analysis of short term metabolic adaptation at dark transition in Synechocystis sp. PCC 6803. J Biosci Bioeng 2019; 128:424-428. [PMID: 30979614 DOI: 10.1016/j.jbiosc.2019.03.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 03/25/2019] [Accepted: 03/25/2019] [Indexed: 12/22/2022]
Abstract
In photosynthetic organisms, such as cyanobacteria, ATP and NADPH are generated through the light reaction, and then are used for CO2 fixation in the dark reaction. As light intensity always fluctuates under natural conditions, balancing the cofactor regeneration and consumption is essential to maintain active CO2 fixation as well as for metabolic engineering of strains that produce biochemicals. In this study, a time-resolved metabolome analysis of Synechocystis sp. PCC 6803 (PCC6803) was conducted to investigate a metabolic adaptation at 0-15 min after a sudden shift from light to dark conditions. Rapid accumulation of sedoheptulose 7-phosphate, ribulose 5-phosphate, xylulose 5-phosphate, and 6-phosphogluconate suggested that the central metabolism of PCC6803 was regulated by inactivation of phosphoribulokinase and activation of glucose-6-phosphate dehydrogenase (G6PDH) probably via the redox regulation. The culture and metabolic profile of the Δzwf strain lacking G6PDH showed that the role of G6PDH in regeneration of NADPH could be complemented by the activation of isocitrate dehydrogenase in the TCA cycle, indicating the importance of the rapid regulation of NADPH regeneration after the shift to dark conditions. The mechanism underlying metabolic regulation is also useful for metabolic engineering of PCC6803, as the Δzwf strain produced higher amount of organic acids than wild type.
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Affiliation(s)
- Masaharu Maruyama
- Department of Bioinformatics Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Hiroki Nishiguchi
- Department of Bioinformatics Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Masakazu Toyoshima
- Department of Bioinformatics Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Nobuyuki Okahashi
- Department of Bioinformatics Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Fumio Matsuda
- Department of Bioinformatics Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Hiroshi Shimizu
- Department of Bioinformatics Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
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Nishiguchi H, Hiasa N, Uebayashi K, Liao J, Shimizu H, Matsuda F. Transomics data-driven, ensemble kinetic modeling for system-level understanding and engineering of the cyanobacteria central metabolism. Metab Eng 2019; 52:273-283. [DOI: 10.1016/j.ymben.2019.01.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 01/05/2019] [Accepted: 01/06/2019] [Indexed: 11/26/2022]
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Tokuyama K, Toya Y, Matsuda F, Cress BF, Koffas MAG, Shimizu H. Magnesium starvation improves production of malonyl-CoA-derived metabolites in Escherichia coli. Metab Eng 2018; 52:215-223. [PMID: 30529031 DOI: 10.1016/j.ymben.2018.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 12/04/2018] [Accepted: 12/05/2018] [Indexed: 12/23/2022]
Abstract
Starvation of essential nutrients, such as nitrogen, sulfur, magnesium, and phosphorus, leads cells into stationary phase and potentially enhances target metabolite production because cells do not consume carbon for the biomass synthesis. The overall metabolic behavior changes depend on the type of nutrient starvation in Escherichia coli. In the present study, we determined the optimum nutrient starvation type for producing malonyl-CoA-derived metabolites such as 3-hydroxypropionic acid (3HP) and naringenin in E. coli. For 3HP production, high production titer (2.3 or 2.0 mM) and high specific production rate (0.14 or 0.28 mmol gCDW-1 h-1) was observed under sulfur or magnesium starvation, whereas almost no 3HP production was detected under nitrogen or phosphorus starvation. Metabolic profiling analysis revealed that the intracellular malonyl-CoA concentration was significantly increased under the 3HP producing conditions. This accumulation should contribute to the 3HP production because malonyl-CoA is a precursor of 3HP. Strong positive correlation (r = 0.95) between intracellular concentrations of ATP and malonyl-CoA indicates that the ATP level is important for malonyl-CoA synthesis due to the ATP requirement by acetyl-CoA carboxylase. For naringenin production, magnesium starvation led to the highest production titer (144 ± 15 μM) and specific productivity (127 ± 21 μmol gCDW-1). These results demonstrated that magnesium starvation is a useful approach to improve the metabolic state of strains engineered for the production of malonyl-CoA derivatives.
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Affiliation(s)
- Kento Tokuyama
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yoshihiro Toya
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Fumio Matsuda
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Brady F Cress
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - Mattheos A G Koffas
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA; Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - Hiroshi Shimizu
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
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19
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Okahashi N, Maeda K, Kawana S, Iida J, Shimizu H, Matsuda F. Sugar phosphate analysis with baseline separation and soft ionization by gas chromatography-negative chemical ionization-mass spectrometry improves flux estimation of bidirectional reactions in cancer cells. Metab Eng 2018; 51:43-49. [PMID: 30176394 DOI: 10.1016/j.ymben.2018.08.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 07/31/2018] [Accepted: 08/29/2018] [Indexed: 11/16/2022]
Abstract
Precise measurement of sugar phosphates in glycolysis and the pentose phosphate (PP) pathway for 13C-metabolic flux analysis (13C-MFA) is needed to understand cancer-specific metabolism. Although various analytical methods have been proposed, analysis of sugar phosphates is challenging because of the structural similarity of various isomers and low intracellular abundance. In this study, gas chromatography-negative chemical ionization-mass spectrometry (GC-NCI-MS) is applied to sugar phosphate analysis with o-(2,3,4,5,6-pentafluorobenzyl) oxime (PFBO) and trimethylsilyl (TMS) derivatization. Optimization of the GC temperature gradient achieved baseline separation of sugar phosphates in 31 min. Mass spectra showed the predominant generation of fragment ions containing all carbon atoms in the sugar phosphate backbone. The limit of detection of pentose 5-phosphates and hexose 6-phosphates was 10 nM. The method was applied to 13C-labeling measurement of sugar phosphates for 13C-MFA of the MCF-7 human breast cancer cell line. 13C-labeling of sugar phosphates for 13C-MFA improved the estimation of the net flux and reversible flux of bidirectional reactions in glycolysis and the PP pathway.
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Affiliation(s)
- Nobuyuki Okahashi
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Kousuke Maeda
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Shuichi Kawana
- Analytical and Measuring Instruments Division, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, Japan.
| | - Junko Iida
- Analytical and Measuring Instruments Division, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, Japan; Osaka University Shimadzu Analytical Innovation Research Laboratory, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka, Japan.
| | - Hiroshi Shimizu
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Fumio Matsuda
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
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Li P, Fu X, Li S, Zhang L. Engineering TATA-binding protein Spt15 to improve ethanol tolerance and production in Kluyveromyces marxianus. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:207. [PMID: 30061929 PMCID: PMC6058363 DOI: 10.1186/s13068-018-1206-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Accepted: 07/16/2018] [Indexed: 05/26/2023]
Abstract
BACKGROUND Low ethanol tolerance of Kluyveromyces marxianus limits its application in high-temperature ethanol fermentation. As a complex phenotype, ethanol tolerance involves synergistic actions of many genes that are widely distributed throughout the genome, thereby being difficult to engineer. TATA-binding protein is the most common target of global transcription machinery engineering for improvement of complex phenotypes. RESULTS A random mutagenesis library of K. marxianus TATA-binding protein Spt15 was constructed and subjected to screening under ethanol stress. Two mutant strains with improved ethanol tolerance were identified, one of which (denoted as M2) exhibited increased ethanol productivity. The mutant of Spt15 in strain M2 (denoted as Spt15-M2) has a single amino acid substitution at position 31 (Lys → Glu). RNA-Seq-based transcriptomic analysis revealed cellular transcription profile changes resulting from Spt15-M2. Spt15-M2 caused changes in transcriptional level of most of the genes in the central carbon metabolism network. Compared with control strain, 444 differentially expressed genes (DEGs) were identified in strain M2 (fold change > 2, Padj < 0.05), including 48 up-regulated and 396 down-regulated. The up-regulated DEGs are involved in amino acid transport, long-chain fatty acid biosynthesis and MAPK signaling pathway, while the down-regulated DEGs are related to ribosome biogenesis, translation and protein synthesis. Five candidate genes (GAP1, GNP1, FAR1, STE2 and TEC1), which were found to be up-regulated in M2 strain, were overexpressed for a gain-of-function assay. However, the overexpression of no single gene helped improve ethanol tolerance as SPT15-M2 did. CONCLUSIONS This work demonstrates that ethanol tolerance of K. marxianus can be improved by engineering its TATA-binding protein. A single amino acid substitution (K31E) of TATA-binding protein Spt15 is able to bring differential expression of hundreds of genes that acted as an interconnected network for the phenotype of ethanol tolerance. Future perspectives of this technique in K. marxianus were discussed.
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Affiliation(s)
- Pengsong Li
- Institute of New Energy Technology, MOST-USDA Joint Research Center for Biofuels, Beijing Engineering Research Center for Biofuels, Tsinghua University, Beijing, 100084 China
| | - Xiaofen Fu
- Institute of New Energy Technology, MOST-USDA Joint Research Center for Biofuels, Beijing Engineering Research Center for Biofuels, Tsinghua University, Beijing, 100084 China
| | - Shizhong Li
- Institute of New Energy Technology, MOST-USDA Joint Research Center for Biofuels, Beijing Engineering Research Center for Biofuels, Tsinghua University, Beijing, 100084 China
| | - Lei Zhang
- Institute of New Energy Technology, MOST-USDA Joint Research Center for Biofuels, Beijing Engineering Research Center for Biofuels, Tsinghua University, Beijing, 100084 China
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21
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Nagai H, Masuda A, Toya Y, Matsuda F, Shimizu H. Metabolic engineering of mevalonate-producing Escherichia coli strains based on thermodynamic analysis. Metab Eng 2018; 47:1-9. [DOI: 10.1016/j.ymben.2018.02.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 12/07/2017] [Accepted: 02/25/2018] [Indexed: 01/07/2023]
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22
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Ishii J, Morita K, Ida K, Kato H, Kinoshita S, Hataya S, Shimizu H, Kondo A, Matsuda F. A pyruvate carbon flux tugging strategy for increasing 2,3-butanediol production and reducing ethanol subgeneration in the yeast Saccharomyces cerevisiae. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:180. [PMID: 29983743 PMCID: PMC6020211 DOI: 10.1186/s13068-018-1176-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 06/16/2018] [Indexed: 05/06/2023]
Abstract
BACKGROUND The yeast Saccharomyces cerevisiae is a promising host cell for producing a wide range of chemicals. However, attempts to metabolically engineer Crabtree-positive S. cerevisiae invariably face a common issue: how to reduce dominant ethanol production. Here, we propose a yeast metabolic engineering strategy for decreasing ethanol subgeneration involving tugging the carbon flux at an important hub branching point (e.g., pyruvate). Tugging flux at a central glycolytic overflow metabolism point arising from high glycolytic activity may substantially increase higher alcohol production in S. cerevisiae. We validated this possibility by testing 2,3-butanediol (2,3-BDO) production, which is routed via pyruvate as the important hub compound. RESULTS By searching for high-activity acetolactate synthase (ALS) enzymes that catalyze the important first-step reaction in 2,3-BDO biosynthesis, and tuning several fermentation conditions, we demonstrated that a stronger pyruvate pulling effect (tugging of pyruvate carbon flux) is very effective for increasing 2,3-BDO production and reducing ethanol subgeneration by S. cerevisiae. To further confirm the validity of the pyruvate carbon flux tugging strategy, we constructed an evolved pyruvate decarboxylase (PDC)-deficient yeast (PDCΔ) strain that lacked three isozymes of PDC. In parallel with re-sequencing to identify genomic mutations, liquid chromatography-tandem mass spectrometry analysis of intermediate metabolites revealed significant accumulation of pyruvate and NADH in the evolved PDCΔ strain. Harnessing the high-activity ALS and additional downstream enzymes in the evolved PDCΔ strain resulted in a high yield of 2,3-BDO (a maximum of 0.41 g g-1 glucose consumed) and no ethanol subgeneration, thereby confirming the utility of our strategy. Using this engineered strain, we demonstrated a high 2,3-BDO titer (81.0 g L-1) in a fed-batch fermentation using a high concentration of glucose as the sole carbon source. CONCLUSIONS We demonstrated that the pyruvate carbon flux tugging strategy is very effective for increasing 2,3-BDO production and decreasing ethanol subgeneration in Crabtree-positive S. cerevisiae. High activity of the common first-step enzyme for the conversion of pyruvate, which links to both the TCA cycle and amino acid biosynthesis, is likely important for the production of various chemicals by S. cerevisiae.
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Affiliation(s)
- Jun Ishii
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501 Japan
| | - Keisuke Morita
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871 Japan
| | - Kengo Ida
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501 Japan
| | - Hiroko Kato
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501 Japan
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871 Japan
| | - Shohei Kinoshita
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871 Japan
| | - Shoko Hataya
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501 Japan
| | - Hiroshi Shimizu
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871 Japan
| | - Akihiko Kondo
- Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501 Japan
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe, 657-8501 Japan
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro, Tsurumi, Yokohama, 230-0045 Japan
| | - Fumio Matsuda
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871 Japan
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro, Tsurumi, Yokohama, 230-0045 Japan
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Matsuda F, Toya Y, Shimizu H. Learning from quantitative data to understand central carbon metabolism. Biotechnol Adv 2017; 35:971-980. [DOI: 10.1016/j.biotechadv.2017.09.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 09/01/2017] [Accepted: 09/14/2017] [Indexed: 12/23/2022]
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Okahashi N, Matsuda F, Yoshikawa K, Shirai T, Matsumoto Y, Wada M, Shimizu H. Metabolic engineering of isopropyl alcohol-producingEscherichia colistrains with13C-metabolic flux analysis. Biotechnol Bioeng 2017; 114:2782-2793. [DOI: 10.1002/bit.26390] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 07/02/2017] [Accepted: 07/27/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Nobuyuki Okahashi
- Department of Bioinfomatic Engineering; Graduate School of Information Science and Technology; Osaka University; Osaka Japan
| | - Fumio Matsuda
- Department of Bioinfomatic Engineering; Graduate School of Information Science and Technology; Osaka University; Osaka Japan
| | - Katsunori Yoshikawa
- Department of Bioinfomatic Engineering; Graduate School of Information Science and Technology; Osaka University; Osaka Japan
| | - Tomokazu Shirai
- Synthetic Chemicals Laboratory; Mitsui Chemicals Inc.; Mobara Chiba Japan
| | - Yoshiko Matsumoto
- Synthetic Chemicals Laboratory; Mitsui Chemicals Inc.; Mobara Chiba Japan
| | - Mitsufumi Wada
- Synthetic Chemicals Laboratory; Mitsui Chemicals Inc.; Mobara Chiba Japan
| | - Hiroshi Shimizu
- Department of Bioinfomatic Engineering; Graduate School of Information Science and Technology; Osaka University; Osaka Japan
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25
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Morita K, Nomura Y, Ishii J, Matsuda F, Kondo A, Shimizu H. Heterologous expression of bacterial phosphoenol pyruvate carboxylase and Entner-Doudoroff pathway in Saccharomyces cerevisiae for improvement of isobutanol production. J Biosci Bioeng 2017; 124:263-270. [PMID: 28539187 DOI: 10.1016/j.jbiosc.2017.04.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 04/07/2017] [Indexed: 11/30/2022]
Abstract
Bacterial phosphoenol pyruvate carboxylase (PPC) and enzymes in the Entner-Doudoroff (ED) pathway were heterologously expressed in Saccharomyces cerevisiae to improve the NADPH supply required for the bio-production of chemicals such as isobutanol. The heterologous expression of PPC from Synechocystis sp. PCC6803 increased in the isobutabol titer 1.45-fold (93.2±1.6 mg/L) in metabolically engineered S. cerevisiae strains producing isobutanol. This result suggested that the pyruvate and NADPH supply for isobutanol biosynthesis was activated by PPC overexpression. On the other hand, the expression of two enzymes organizing the ED pathway (6-phosphogluconate dehydratase [6PGD] and 2-dehydro-3-deoxy-phosphogluconate aldolase [KDPGA]) had no effect to isobutabol bio-production. Further analysis, however, revealed that additional expression of 6PGD and KDPGA improved the growth rate of S. cerevisiae strain BY4742 gnd1Δ. A 13C-labeling experiment using [1-13C] glucose also suggested that metabolic flow levels in the ED pathway increased slightly with the additional expression. These results showed that the ED pathway was successfully constructed in S. cerevisiae, even though activity of the pathway was too weak to improve isobutanol biosynthesis.
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Affiliation(s)
- Keisuke Morita
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Yuta Nomura
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Jun Ishii
- Graduate School of Science, Technology, and Innovation, Kobe University, 1-1 Rokkodaicho, Nada, Kobe 657-8501, Japan.
| | - Fumio Matsuda
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Akihiko Kondo
- Graduate School of Science, Technology, and Innovation, Kobe University, 1-1 Rokkodaicho, Nada, Kobe 657-8501, Japan.
| | - Hiroshi Shimizu
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
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26
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Single Cell Protein Production by Saccharomyces cerevisiae Using an Optimized Culture Medium Composition in a Batch Submerged Bioprocess. Appl Biochem Biotechnol 2016; 179:1336-45. [DOI: 10.1007/s12010-016-2069-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 03/30/2016] [Indexed: 10/21/2022]
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