1
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Tian Z, Liu L, Wu L, Yang Z, Zhang Y, Du L, Zhang D. Enhancement of vitamin B 6 production driven by omics analysis combined with fermentation optimization. Microb Cell Fact 2024; 23:137. [PMID: 38750497 PMCID: PMC11095007 DOI: 10.1186/s12934-024-02405-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 04/24/2024] [Indexed: 05/19/2024] Open
Abstract
BACKGROUND Microbial engineering aims to enhance the ability of bacteria to produce valuable products, including vitamin B6 for various applications. Numerous microorganisms naturally produce vitamin B6, yet the metabolic pathways involved are rigorously controlled. This regulation by the accumulation of vitamin B6 poses a challenge in constructing an efficient cell factory. RESULTS In this study, we conducted transcriptome and metabolome analyses to investigate the effects of the accumulation of pyridoxine, which is the major commercial form of vitamin B6, on cellular processes in Escherichia coli. Our omics analysis revealed associations between pyridoxine and amino acids, as well as the tricarboxylic acid (TCA) cycle. Based on these findings, we identified potential targets for fermentation optimization, including succinate, amino acids, and the carbon-to-nitrogen (C/N) ratio. Through targeted modifications, we achieved pyridoxine titers of approximately 514 mg/L in shake flasks and 1.95 g/L in fed-batch fermentation. CONCLUSION Our results provide insights into pyridoxine biosynthesis within the cellular metabolic network for the first time. Our comprehensive analysis revealed that the fermentation process resulted in a remarkable final yield of 1.95 g/L pyridoxine, the highest reported yield to date. This work lays a foundation for the green industrial production of vitamin B6 in the future.
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Affiliation(s)
- Zhizhong Tian
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Linxia Liu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308, China
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Lijuan Wu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Zixuan Yang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Yahui Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
| | - Liping Du
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, China.
| | - Dawei Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
- National Center of Technology Innovation for Synthetic Biology, Tianjin, 300308, China.
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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2
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Liu L, Li J, Gai Y, Tian Z, Wang Y, Wang T, Liu P, Yuan Q, Ma H, Lee SY, Zhang D. Protein engineering and iterative multimodule optimization for vitamin B 6 production in Escherichia coli. Nat Commun 2023; 14:5304. [PMID: 37652926 PMCID: PMC10471632 DOI: 10.1038/s41467-023-40928-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 08/16/2023] [Indexed: 09/02/2023] Open
Abstract
Vitamin B6 is an essential nutrient with extensive applications in the medicine, food, animal feed, and cosmetics industries. Pyridoxine (PN), the most common commercial form of vitamin B6, is currently chemically synthesized using expensive and toxic chemicals. However, the low catalytic efficiencies of natural enzymes and the tight regulation of the metabolic pathway have hindered PN production by the microbial fermentation process. Here, we report an engineered Escherichia coli strain for PN production. Parallel pathway engineering is performed to decouple PN production and cell growth. Further, protein engineering is rationally designed including the inefficient enzymes PdxA, PdxJ, and the initial enzymes Epd and Dxs. By the iterative multimodule optimization strategy, the final strain produces 1.4 g/L of PN with productivity of 29.16 mg/L/h by fed-batch fermentation. The strategies reported here will be useful for developing microbial strains for the production of vitamins and other bioproducts having inherently low metabolic fluxes.
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Affiliation(s)
- Linxia Liu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- National Technology Innovation Center of Synthetic Biology, Tianjin, China
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Jinlong Li
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yuanming Gai
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
- National Technology Innovation Center of Synthetic Biology, Tianjin, China
| | - Zhizhong Tian
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Yanyan Wang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Tenghe Wang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Pi Liu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Qianqian Yuan
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Hongwu Ma
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Sang Yup Lee
- Department of Chemical and Biomolecular Engineering (BK21 four program), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
| | - Dawei Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.
- National Technology Innovation Center of Synthetic Biology, Tianjin, China.
- Key Laboratory of Engineering Biology for Low-Carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.
- University of Chinese Academy of Sciences, Beijing, China.
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3
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Richts B, Commichau FM. Underground metabolism facilitates the evolution of novel pathways for vitamin B6 biosynthesis. Appl Microbiol Biotechnol 2021; 105:2297-2305. [PMID: 33665688 PMCID: PMC7954711 DOI: 10.1007/s00253-021-11199-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/15/2021] [Accepted: 02/24/2021] [Indexed: 11/29/2022]
Abstract
Abstract The term vitamin B6 is a designation for the vitamers pyridoxal, pyridoxamine, pyridoxine and the respective phosphate esters pyridoxal-5′-phosphate (PLP), pyridoxamine-5′-phosphate and pyridoxine-5′-phosphate. Animals and humans are unable to synthesise vitamin B6. These organisms have to take up vitamin B6 with their diet. Therefore, vitamin B6 is of commercial interest as a food additive and for applications in the pharmaceutical industry. As yet, two naturally occurring routes for de novo synthesis of PLP are known. Both routes have been genetically engineered to obtain bacteria overproducing vitamin B6. Still, major genetic engineering efforts using the existing pathways are required for developing fermentation processes that could outcompete the chemical synthesis of vitamin B6. Recent suppressor screens using mutants of the Gram-negative and Gram-positive model bacteria Escherichia coli and Bacillus subtilis, respectively, carrying mutations in the native pathways or heterologous genes uncovered novel routes for PLP biosynthesis. These pathways consist of promiscuous enzymes and enzymes that are already involved in vitamin B6 biosynthesis. Thus, E. coli and B. subtilis contain multiple promiscuous enzymes causing a so-called underground metabolism allowing the bacteria to bypass disrupted vitamin B6 biosynthetic pathways. The suppressor screens also show the genomic plasticity of the bacteria to suppress a genetic lesion. We discuss the potential of the serendipitous pathways to serve as a starting point for the development of bacteria overproducing vitamin B6. Key points • Known vitamin B6 routes have been genetically engineered. • Underground metabolism facilitates the emergence of novel vitamin B6 biosynthetic pathways. • These pathways may be suitable to engineer bacteria overproducing vitamin B6.
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Affiliation(s)
- Björn Richts
- Department of General Microbiology, Institute for Microbiology and Genetics, University of Goettingen, Grisebachstrasse 8, 37077, Göttingen, Germany
| | - Fabian M Commichau
- FG Synthetic Microbiology, Institute for Biotechnology, BTU Cottbus-Senftenberg, Universitätsplatz 1, 01968, Senftenberg, Germany.
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4
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Huddleston JP, Raushel FM. Functional Characterization of Cj1427, a Unique Ping-Pong Dehydrogenase Responsible for the Oxidation of GDP-d- glycero-α-d- manno-heptose in Campylobacter jejuni. Biochemistry 2020; 59:1328-1337. [PMID: 32168448 PMCID: PMC7500870 DOI: 10.1021/acs.biochem.0c00097] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The capsular polysaccharides (CPS) of Campylobacter jejuni contain multiple heptose residues with variable stereochemical arrangements at C3-C6. The immediate precursor to all of these possible variations is currently believed to be GDP-d-glycero-α-d-manno-heptose. Oxidation of this substrate at C4 enables subsequent epimerization reactions at C3-C5 that can be coupled to the dehydration/reduction at C5/C6. However, the enzyme responsible for the critical oxidation of C4 from GDP-d-glycero-α-d-manno-heptose has remained elusive. The enzyme Cj1427 from C. jejuni NCTC 11168 was shown to catalyze the oxidation of GDP-d-glycero-α-d-manno-heptose to GDP-d-glycero-4-keto-α-d-lyxo-heptose in the presence of α-ketoglutarate using mass spectrometry and nuclear magnetic resonance spectroscopy. At pH 7.4, the apparent kcat is 0.6 s-1, with a value of kcat/Km of 1.0 × 104 M-1 s-1 for GDP-d-glycero-α-d-manno-heptose. α-Ketoglutarate is required to recycle the tightly bound NADH nucleotide in the active site of Cj1427, which does not dissociate from the enzyme during catalysis.
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Affiliation(s)
- Jamison P. Huddleston
- Department of Chemistry, Texas A&M University, College Station, Texas, 77843, United States
| | - Frank M. Raushel
- Department of Chemistry, Texas A&M University, College Station, Texas, 77843, United States
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas 77843, United States
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5
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Huddleston JP, Anderson TK, Spencer KD, Thoden JB, Raushel FM, Holden HM. Structural Analysis of Cj1427, an Essential NAD-Dependent Dehydrogenase for the Biosynthesis of the Heptose Residues in the Capsular Polysaccharides of Campylobacter jejuni. Biochemistry 2020; 59:1314-1327. [PMID: 32168450 DOI: 10.1021/acs.biochem.0c00096] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Many strains of Campylobacter jejuni display modified heptose residues in their capsular polysaccharides (CPS). The precursor heptose was previously shown to be GDP-d-glycero-α-d-manno-heptose, from which a variety of modifications of the sugar moiety have been observed. These modifications include the generation of 6-deoxy derivatives and alterations of the stereochemistry at C3-C6. Previous work has focused on the enzymes responsible for the generation of the 6-deoxy derivatives and those involved in altering the stereochemistry at C3 and C5. However, the generation of the 6-hydroxyl heptose residues remains uncertain due to the lack of a specific enzyme to catalyze the initial oxidation at C4 of GDP-d-glycero-α-d-manno-heptose. Here we reexamine the previously reported role of Cj1427, a dehydrogenase found in C. jejuni NTCC 11168 (HS:2). We show that Cj1427 is co-purified with bound NADH, thus hindering catalysis of oxidation reactions. However, addition of a co-substrate, α-ketoglutarate, converts the bound NADH to NAD+. In this form, Cj1427 catalyzes the oxidation of l-2-hydroxyglutarate back to α-ketoglutarate. The crystal structure of Cj1427 with bound GDP-d-glycero-α-d-manno-heptose shows that the NAD(H) cofactor is ideally positioned to catalyze the oxidation at C4 of the sugar substrate. Additionally, the overall fold of the Cj1427 subunit places it into the well-defined short-chain dehydrogenase/reductase superfamily. The observed quaternary structure of the tetrameric enzyme, however, is highly unusual for members of this superfamily.
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Affiliation(s)
- Jamison P Huddleston
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Thomas K Anderson
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Keelan D Spencer
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - James B Thoden
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Frank M Raushel
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States.,Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas 77843, United States
| | - Hazel M Holden
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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6
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Richts B, Rosenberg J, Commichau FM. A Survey of Pyridoxal 5'-Phosphate-Dependent Proteins in the Gram-Positive Model Bacterium Bacillus subtilis. Front Mol Biosci 2019; 6:32. [PMID: 31134210 PMCID: PMC6522883 DOI: 10.3389/fmolb.2019.00032] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 04/18/2019] [Indexed: 11/13/2022] Open
Abstract
The B6 vitamer pyridoxal 5′-phosphate (PLP) is a co-factor for proteins and enzymes that are involved in diverse cellular processes. Therefore, PLP is essential for organisms from all kingdoms of life. Here we provide an overview about the PLP-dependent proteins from the Gram-positive soil bacterium Bacillus subtilis. Since B. subtilis serves as a model system in basic research and as a production host in industry, knowledge about the PLP-dependent proteins could facilitate engineering the bacteria for biotechnological applications. The survey revealed that the majority of the PLP-dependent proteins are involved in metabolic pathways like amino acid biosynthesis and degradation, biosynthesis of antibacterial compounds, utilization of nucleotides as well as in iron and carbon metabolism. Many PLP-dependent proteins participate in de novo synthesis of the co-factors biotin, folate, heme, and NAD+ as well as in cell wall metabolism, tRNA modification, regulation of gene expression, sporulation, and biofilm formation. A surprisingly large group of PLP-dependent proteins (29%) belong to the group of poorly characterized proteins. This review underpins the need to characterize the PLP-dependent proteins of unknown function to fully understand the “PLP-ome” of B. subtilis.
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Affiliation(s)
- Björn Richts
- Department of General Microbiology, University of Goettingen, Göttingen, Germany
| | - Jonathan Rosenberg
- Department of General Microbiology, University of Goettingen, Göttingen, Germany
| | - Fabian M Commichau
- Department of General Microbiology, University of Goettingen, Göttingen, Germany
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7
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Paczia N, Becker-Kettern J, Conrotte JF, Cifuente JO, Guerin ME, Linster CL. 3-Phosphoglycerate Transhydrogenation Instead of Dehydrogenation Alleviates the Redox State Dependency of Yeast de Novo l-Serine Synthesis. Biochemistry 2019; 58:259-275. [PMID: 30668112 DOI: 10.1021/acs.biochem.8b00990] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The enzymatic mechanism of 3-phosphoglycerate to 3-phosphohydroxypyruvate oxidation, which forms the first step of the main conserved de novo serine synthesis pathway, has been revisited recently in certain microorganisms. While this step is classically considered to be catalyzed by an NAD-dependent dehydrogenase (e.g., PHGDH in mammals), evidence has shown that in Pseudomonas, Escherichia coli, and Saccharomyces cerevisiae, the PHGDH homologues act as transhydrogenases. As such, they use α-ketoglutarate, rather than NAD+, as the final electron acceptor, thereby producing D-2-hydroxyglutarate in addition to 3-phosphohydroxypyruvate during 3-phosphoglycerate oxidation. Here, we provide a detailed biochemical and sequence-structure relationship characterization of the yeast PHGDH homologues, encoded by the paralogous SER3 and SER33 genes, in comparison to the human and other PHGDH enzymes. Using in vitro assays with purified recombinant enzymes as well as in vivo growth phenotyping and metabolome analyses of yeast strains engineered to depend on either Ser3, Ser33, or human PHGDH for serine synthesis, we confirmed that both yeast enzymes act as transhydrogenases, while the human enzyme is a dehydrogenase. In addition, we show that the yeast paralogs differ from the human enzyme in their sensitivity to inhibition by serine as well as hydrated NADH derivatives. Importantly, our in vivo data support the idea that a 3PGA transhydrogenase instead of dehydrogenase activity confers a growth advantage under conditions where the NAD+:NADH ratio is low. The results will help to elucidate why different species evolved different reaction mechanisms to carry out a widely conserved metabolic step in central carbon metabolism.
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Affiliation(s)
- Nicole Paczia
- Luxembourg Centre for Systems Biomedicine , University of Luxembourg , L-4367 Belvaux , Luxembourg
| | - Julia Becker-Kettern
- Luxembourg Centre for Systems Biomedicine , University of Luxembourg , L-4367 Belvaux , Luxembourg
| | - Jean-François Conrotte
- Luxembourg Centre for Systems Biomedicine , University of Luxembourg , L-4367 Belvaux , Luxembourg
| | - Javier O Cifuente
- Structural Biology Unit , CIC bioGUNE Technological Park of Bizkaia , 48160 Derio , Vizcaya , Spain
| | - Marcelo E Guerin
- Structural Biology Unit , CIC bioGUNE Technological Park of Bizkaia , 48160 Derio , Vizcaya , Spain.,IKERBASQUE , Basque Foundation for Science , 48013 Bilbao , Spain
| | - Carole L Linster
- Luxembourg Centre for Systems Biomedicine , University of Luxembourg , L-4367 Belvaux , Luxembourg
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8
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Relation of the pdxB-usg- truA- dedA Operon and the truA Gene to the Intracellular Survival of Salmonella enterica Serovar Typhimurium. Int J Mol Sci 2019; 20:ijms20020380. [PMID: 30658401 PMCID: PMC6358828 DOI: 10.3390/ijms20020380] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/11/2019] [Accepted: 01/15/2019] [Indexed: 11/28/2022] Open
Abstract
Salmonella is the genus of Gram-negative, facultative intracellular pathogens that have the ability to infect large numbers of animal or human hosts. The S. enterica usg gene is associated with intracellular survival based on ortholog screening and identification. In this study, the λ-Red recombination system was used to construct gene deletion strains and to investigate whether the identified operon was related to intracellular survival. The pdxB-usg-truA-dedA operon enhanced the intracellular survival of S. enterica by resisting the oxidative environment and the usg and truA gene expression was induced by H2O2. Moreover, the genes in this operon (except for dedA) contributed to virulence in mice. These findings indicate that the pdxB-usg-truA-dedA operon functions in resistance to oxidative environments during intracellular survival and is required for in vivo S. enterica virulence. This study provides insight toward a better understand of the characteristics of intracellular pathogens and explores the gene modules involved in their intracellular survival.
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9
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Matelska D, Shabalin IG, Jabłońska J, Domagalski MJ, Kutner J, Ginalski K, Minor W. Classification, substrate specificity and structural features of D-2-hydroxyacid dehydrogenases: 2HADH knowledgebase. BMC Evol Biol 2018; 18:199. [PMID: 30577795 PMCID: PMC6303947 DOI: 10.1186/s12862-018-1309-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 11/27/2018] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND The family of D-isomer specific 2-hydroxyacid dehydrogenases (2HADHs) contains a wide range of oxidoreductases with various metabolic roles as well as biotechnological applications. Despite a vast amount of biochemical and structural data for various representatives of the family, the long and complex evolution and broad sequence diversity hinder functional annotations for uncharacterized members. RESULTS We report an in-depth phylogenetic analysis, followed by mapping of available biochemical and structural data on the reconstructed phylogenetic tree. The analysis suggests that some subfamilies comprising enzymes with similar yet broad substrate specificity profiles diverged early in the evolution of 2HADHs. Based on the phylogenetic tree, we present a revised classification of the family that comprises 22 subfamilies, including 13 new subfamilies not studied biochemically. We summarize characteristics of the nine biochemically studied subfamilies by aggregating all available sequence, biochemical, and structural data, providing comprehensive descriptions of the active site, cofactor-binding residues, and potential roles of specific structural regions in substrate recognition. In addition, we concisely present our analysis as an online 2HADH enzymes knowledgebase. CONCLUSIONS The knowledgebase enables navigation over the 2HADHs classification, search through collected data, and functional predictions of uncharacterized 2HADHs. Future characterization of the new subfamilies may result in discoveries of enzymes with novel metabolic roles and with properties beneficial for biotechnological applications.
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Affiliation(s)
- Dorota Matelska
- Department of Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA, 22908, USA.,Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02-089, Warsaw, Poland
| | - Ivan G Shabalin
- Department of Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA, 22908, USA.,Center for Structural Genomics of Infectious Diseases (CSGID), Charlottesville, VA, 22908, USA
| | - Jagoda Jabłońska
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02-089, Warsaw, Poland
| | - Marcin J Domagalski
- Department of Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA, 22908, USA.,Center for Structural Genomics of Infectious Diseases (CSGID), Charlottesville, VA, 22908, USA
| | - Jan Kutner
- Department of Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA, 22908, USA.,Laboratory for Structural and Biochemical Research, Biological and Chemical Research Centre, Department of Chemistry, University of Warsaw, Zwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Krzysztof Ginalski
- Laboratory of Bioinformatics and Systems Biology, Centre of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02-089, Warsaw, Poland.
| | - Wladek Minor
- Department of Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA, 22908, USA. .,Center for Structural Genomics of Infectious Diseases (CSGID), Charlottesville, VA, 22908, USA. .,Department of Chemistry, University of Warsaw, Ludwika Pasteura 1, 02-093, Warsaw, Poland.
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10
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Becker-Kettern J, Paczia N, Conrotte JF, Zhu C, Fiehn O, Jung PP, Steinmetz LM, Linster CL. NAD(P)HX repair deficiency causes central metabolic perturbations in yeast and human cells. FEBS J 2018; 285:3376-3401. [PMID: 30098110 DOI: 10.1111/febs.14631] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 06/20/2018] [Accepted: 08/08/2018] [Indexed: 12/20/2022]
Abstract
NADHX and NADPHX are hydrated and redox inactive forms of the NADH and NADPH cofactors, known to inhibit several dehydrogenases in vitro. A metabolite repair system that is conserved in all domains of life and that comprises the two enzymes NAD(P)HX dehydratase and NAD(P)HX epimerase, allows reconversion of both the S- and R-epimers of NADHX and NADPHX to the normal cofactors. An inherited deficiency in this system has recently been shown to cause severe neurometabolic disease in children. Although evidence for the presence of NAD(P)HX has been obtained in plant and human cells, little is known about the mechanism of formation of these derivatives in vivo and their potential effects on cell metabolism. Here, we show that NAD(P)HX dehydratase deficiency in yeast leads to an important, temperature-dependent NADHX accumulation in quiescent cells with a concomitant depletion of intracellular NAD+ and serine pools. We demonstrate that NADHX potently inhibits the first step of the serine synthesis pathway in yeast. Human cells deficient in the NAD(P)HX dehydratase also accumulated NADHX and showed decreased viability. In addition, those cells consumed more glucose and produced more lactate, potentially indicating impaired mitochondrial function. Our results provide first insights into how NADHX accumulation affects cellular functions and pave the way for a better understanding of the mechanism(s) underlying the rapid and severe neurodegeneration leading to early death in NADHX repair-deficient children.
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Affiliation(s)
- Julia Becker-Kettern
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Belvaux, Luxembourg
| | - Nicole Paczia
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Belvaux, Luxembourg
| | - Jean-François Conrotte
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Belvaux, Luxembourg
| | - Chenchen Zhu
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, Heidelberg, Germany
| | - Oliver Fiehn
- NIH West Coast Metabolomics Center, University of California Davis, CA, USA
| | - Paul P Jung
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Belvaux, Luxembourg
| | - Lars M Steinmetz
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, Heidelberg, Germany.,Stanford Genome Technology Center, Stanford University, Palo Alto, CA, USA.,Department of Genetics, Stanford University School of Medicine, CA, USA
| | - Carole L Linster
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Belvaux, Luxembourg
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11
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Guo X, Zhang M, Cao M, Zhang W, Kang Z, Xu P, Ma C, Gao C. d-2-Hydroxyglutarate dehydrogenase plays a dual role in l-serine biosynthesis and d-malate utilization in the bacterium Pseudomonas stutzeri. J Biol Chem 2018; 293:15513-15523. [PMID: 30131334 DOI: 10.1074/jbc.ra118.003897] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/29/2018] [Indexed: 02/03/2023] Open
Abstract
Pseudomonas is a very large bacterial genus in which several species can use d-malate for growth. However, the enzymes that can metabolize d-malate, such as d-malate dehydrogenase, appear to be absent in most Pseudomonas species. d-3-Phosphoglycerate dehydrogenase (SerA) can catalyze the production of d-2-hydroxyglutarate (d-2-HG) from 2-ketoglutarate to support d-3-phosphoglycerate dehydrogenation, which is the initial reaction in bacterial l-serine biosynthesis. In this study, we show that SerA of the Pseudomonas stutzeri strain A1501 reduces oxaloacetate to d-malate and that d-2-HG dehydrogenase (D2HGDH) from P. stutzeri displays d-malate-oxidizing activity. Of note, D2HGDH participates in converting a trace amount of d-malate to oxaloacetate during bacterial l-serine biosynthesis. Moreover, D2HGDH is crucial for the utilization of d-malate as the sole carbon source for growth of P. stutzeri A1501. We also found that the D2HGDH expression is induced by the exogenously added d-2-HG or d-malate and that a flavoprotein functions as a soluble electron carrier between D2HGDH and electron transport chains to support d-malate utilization by P. stutzeri These results support the idea that D2HGDH evolves as an enzyme for both d-malate and d-2-HG dehydrogenation in P. stutzeri In summary, D2HGDH from P. stutzeri A1501 participates in both a core metabolic pathway for l-serine biosynthesis and utilization of extracellular d-malate.
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Affiliation(s)
- Xiaoting Guo
- From the State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China
| | - Manman Zhang
- From the State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China
| | - Menghao Cao
- From the State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China
| | - Wen Zhang
- the Institute of Medical Sciences, Second Hospital of Shandong University, Jinan 250033, China, and
| | - Zhaoqi Kang
- From the State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China
| | - Ping Xu
- the State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Cuiqing Ma
- From the State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China
| | - Chao Gao
- From the State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China,
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12
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Rosenberg J, Yeak KC, Commichau FM. A two-step evolutionary process establishes a non-native vitamin B6 pathway in Bacillus subtilis. Environ Microbiol 2017; 20:156-168. [PMID: 29027347 DOI: 10.1111/1462-2920.13950] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 09/22/2017] [Accepted: 09/27/2017] [Indexed: 12/11/2022]
Abstract
Pyridoxal 5'-phosphate (PLP), the most important form of vitamin B6 serves as a cofactor for many proteins. Two alternative pathways for de novo PLP biosynthesis are known: the short deoxy-xylulose-5-phosphate (DXP)-independent pathway, which is present in the Gram-positive model bacterium Bacillus subtilis and the longer DXP-dependent pathway, which has been intensively studied in the Gram-negative model bacterium Escherichia coli. Previous studies revealed that bacteria contain many promiscuous enzymes causing a so-called 'underground metabolism', which can be important for the evolution of novel pathways. Here, we evaluated the potential of B. subtilis to use a truncated non-native DXP-dependent PLP pathway from E. coli for PLP synthesis. Adaptive laboratory evolution experiments revealed that two non-native enzymes catalysing the last steps of the DXP-dependent PLP pathway and two genomic alterations are sufficient to allow growth of vitamin B6 auxotrophic bacteria as rapid as the wild type. Thus, the existence of an underground metabolism in B. subtilis facilitates the generation of a pathway for synthesis of PLP using parts of a non-native vitamin B6 pathway. The introduction of non-native enzymes into a metabolic network and rewiring of native metabolism could be helpful to generate pathways that might be optimized for producing valuable substances.
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Affiliation(s)
- Jonathan Rosenberg
- Department of General Microbiology, Institute for Microbiology and Genetics, Georg-August-University Göttingen, Göttingen, Germany
| | - KahYen C Yeak
- Department of General Microbiology, Institute for Microbiology and Genetics, Georg-August-University Göttingen, Göttingen, Germany
| | - Fabian M Commichau
- Department of General Microbiology, Institute for Microbiology and Genetics, Georg-August-University Göttingen, Göttingen, Germany
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13
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Coupling between d-3-phosphoglycerate dehydrogenase and d-2-hydroxyglutarate dehydrogenase drives bacterial l-serine synthesis. Proc Natl Acad Sci U S A 2017; 114:E7574-E7582. [PMID: 28827360 DOI: 10.1073/pnas.1619034114] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
l-Serine biosynthesis, a crucial metabolic process in most domains of life, is initiated by d-3-phosphoglycerate (d-3-PG) dehydrogenation, a thermodynamically unfavorable reaction catalyzed by d-3-PG dehydrogenase (SerA). d-2-Hydroxyglutarate (d-2-HG) is traditionally viewed as an abnormal metabolite associated with cancer and neurometabolic disorders. Here, we reveal that bacterial anabolism and catabolism of d-2-HG are involved in l-serine biosynthesis in Pseudomonas stutzeri A1501 and Pseudomonas aeruginosa PAO1. SerA catalyzes the stereospecific reduction of 2-ketoglutarate (2-KG) to d-2-HG, responsible for the major production of d-2-HG in vivo. SerA combines the energetically favorable reaction of d-2-HG production to overcome the thermodynamic barrier of d-3-PG dehydrogenation. We identified a bacterial d-2-HG dehydrogenase (D2HGDH), a flavin adenine dinucleotide (FAD)-dependent enzyme, that converts d-2-HG back to 2-KG. Electron transfer flavoprotein (ETF) and ETF-ubiquinone oxidoreductase (ETFQO) are also essential in d-2-HG metabolism through their capacity to transfer electrons from D2HGDH. Furthermore, while the mutant with D2HGDH deletion displayed decreased growth, the defect was rescued by adding l-serine, suggesting that the D2HGDH is functionally tied to l-serine synthesis. Substantial flux flows through d-2-HG, being produced by SerA and removed by D2HGDH, ETF, and ETFQO, maintaining d-2-HG homeostasis. Overall, our results uncover that d-2-HG-mediated coupling between SerA and D2HGDH drives bacterial l-serine synthesis.
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14
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Haft DH, Pierce PG, Mayclin SJ, Sullivan A, Gardberg AS, Abendroth J, Begley DW, Phan IQ, Staker BL, Myler PJ, Marathias VM, Lorimer DD, Edwards TE. Mycofactocin-associated mycobacterial dehydrogenases with non-exchangeable NAD cofactors. Sci Rep 2017; 7:41074. [PMID: 28120876 PMCID: PMC5264612 DOI: 10.1038/srep41074] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 12/12/2016] [Indexed: 01/08/2023] Open
Abstract
During human infection, Mycobacterium tuberculosis (Mtb) survives the normally bacteriocidal phagosome of macrophages. Mtb and related species may be able to combat this harsh acidic environment which contains reactive oxygen species due to the mycobacterial genomes encoding a large number of dehydrogenases. Typically, dehydrogenase cofactor binding sites are open to solvent, which allows NAD/NADH exchange to support multiple turnover. Interestingly, mycobacterial short chain dehydrogenases/reductases (SDRs) within family TIGR03971 contain an insertion at the NAD binding site. Here we present crystal structures of 9 mycobacterial SDRs in which the insertion buries the NAD cofactor except for a small portion of the nicotinamide ring. Line broadening and STD-NMR experiments did not show NAD or NADH exchange on the NMR timescale. STD-NMR demonstrated binding of the potential substrate carveol, the potential product carvone, the inhibitor tricyclazol, and an external redox partner 2,6-dichloroindophenol (DCIP). Therefore, these SDRs appear to contain a non-exchangeable NAD cofactor and may rely on an external redox partner, rather than cofactor exchange, for multiple turnover. Incidentally, these genes always appear in conjunction with the mftA gene, which encodes the short peptide MftA, and with other genes proposed to convert MftA into the external redox partner mycofactocin.
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Affiliation(s)
- Daniel H Haft
- National Institutes of Health (NIH), Bethesda, MD 20892, USA
| | - Phillip G Pierce
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Beryllium Discovery Corp., 7869 NE Day Road West, Bainbridge Island, WA 98110, USA
| | - Stephen J Mayclin
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Beryllium Discovery Corp., 7869 NE Day Road West, Bainbridge Island, WA 98110, USA
| | - Amy Sullivan
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Beryllium Discovery Corp., 7869 NE Day Road West, Bainbridge Island, WA 98110, USA
| | - Anna S Gardberg
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Beryllium Discovery Corp., 7869 NE Day Road West, Bainbridge Island, WA 98110, USA
| | - Jan Abendroth
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Beryllium Discovery Corp., 7869 NE Day Road West, Bainbridge Island, WA 98110, USA
| | - Darren W Begley
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Beryllium Discovery Corp., 7869 NE Day Road West, Bainbridge Island, WA 98110, USA
| | - Isabelle Q Phan
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Center for Infectious Disease Research (formerly Seattle Biomedical Research Institute), 307 Westlake Avenue North, Seattle WA 98109, USA
| | - Bart L Staker
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Center for Infectious Disease Research (formerly Seattle Biomedical Research Institute), 307 Westlake Avenue North, Seattle WA 98109, USA
| | - Peter J Myler
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Center for Infectious Disease Research (formerly Seattle Biomedical Research Institute), 307 Westlake Avenue North, Seattle WA 98109, USA.,University of Washington, Department of Medical Education and Biomedical Informatics &Department of Global Health, Seattle WA 98195, USA
| | - Vasilios M Marathias
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Beryllium Discovery Corp., 7869 NE Day Road West, Bainbridge Island, WA 98110, USA
| | - Donald D Lorimer
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Beryllium Discovery Corp., 7869 NE Day Road West, Bainbridge Island, WA 98110, USA
| | - Thomas E Edwards
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, WA 98109, USA.,Beryllium Discovery Corp., 7869 NE Day Road West, Bainbridge Island, WA 98110, USA
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15
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Rosenberg J, Ischebeck T, Commichau FM. Vitamin B6 metabolism in microbes and approaches for fermentative production. Biotechnol Adv 2016; 35:31-40. [PMID: 27890703 DOI: 10.1016/j.biotechadv.2016.11.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 11/21/2016] [Accepted: 11/21/2016] [Indexed: 12/20/2022]
Abstract
Vitamin B6 is a designation for the six vitamers pyridoxal, pyridoxine, pyridoxamine, pyridoxal 5'-phosphate (PLP), pyridoxine 5'-phosphate, and pyridoxamine. PLP, being the most important B6 vitamer, serves as a cofactor for many proteins and enzymes. In contrast to other organisms, animals and humans have to ingest vitamin B6 with their food. Several disorders are associated with vitamin B6 deficiency. Moreover, pharmaceuticals interfere with metabolism of the cofactor, which also results in vitamin B6 deficiency. Therefore, vitamin B6 is a valuable compound for the pharmaceutical and the food industry. Although vitamin B6 is currently chemically synthesized, there is considerable interest on the industrial side to shift from chemical processes to sustainable fermentation technologies. Here, we review recent findings regarding biosynthesis and homeostasis of vitamin B6 and describe the approaches that have been made in the past to develop microbial production processes. Moreover, we will describe novel routes for vitamin B6 biosynthesis and discuss their potential for engineering bacteria that overproduce the commercially valuable substance. We also highlight bottlenecks of the vitamin B6 biosynthetic pathways and propose strategies to circumvent these limitations.
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Affiliation(s)
- Jonathan Rosenberg
- Department of General Microbiology, Georg-August-University of Göttingen, Grisebachstr. 8, D-37077 Göttingen, Germany
| | - Till Ischebeck
- Department of Plant Biochemistry, Georg-August-University of Göttingen, Justus-von-Liebig-Weg 11, D-37077 Göttingen, Germany
| | - Fabian M Commichau
- Department of General Microbiology, Georg-August-University of Göttingen, Grisebachstr. 8, D-37077 Göttingen, Germany.
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16
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Becker-Kettern J, Paczia N, Conrotte JF, Kay DP, Guignard C, Jung PP, Linster CL. Saccharomyces cerevisiae Forms D-2-Hydroxyglutarate and Couples Its Degradation to D-Lactate Formation via a Cytosolic Transhydrogenase. J Biol Chem 2016; 291:6036-58. [PMID: 26774271 DOI: 10.1074/jbc.m115.704494] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Indexed: 12/23/2022] Open
Abstract
The D or L form of 2-hydroxyglutarate (2HG) accumulates in certain rare neurometabolic disorders, and high D-2-hydroxyglutarate (D-2HG) levels are also found in several types of cancer. Although 2HG has been detected in Saccharomyces cerevisiae, its metabolism in yeast has remained largely unexplored. Here, we show that S. cerevisiae actively forms the D enantiomer of 2HG. Accordingly, the S. cerevisiae genome encodes two homologs of the human D-2HG dehydrogenase: Dld2, which, as its human homolog, is a mitochondrial protein, and the cytosolic protein Dld3. Intriguingly, we found that a dld3Δ knock-out strain accumulates millimolar levels of D-2HG, whereas a dld2Δ knock-out strain displayed only very moderate increases in D-2HG. Recombinant Dld2 and Dld3, both currently annotated as D-lactate dehydrogenases, efficiently oxidized D-2HG to α-ketoglutarate. Depletion of D-lactate levels in the dld3Δ, but not in the dld2Δ mutant, led to the discovery of a new type of enzymatic activity, carried by Dld3, to convert D-2HG to α-ketoglutarate, namely an FAD-dependent transhydrogenase activity using pyruvate as a hydrogen acceptor. We also provide evidence that Ser3 and Ser33, which are primarily known for oxidizing 3-phosphoglycerate in the main serine biosynthesis pathway, in addition reduce α-ketoglutarate to D-2HG using NADH and represent major intracellular sources of D-2HG in yeast. Based on our observations, we propose that D-2HG is mainly formed and degraded in the cytosol of S. cerevisiae cells in a process that couples D-2HG metabolism to the shuttling of reducing equivalents from cytosolic NADH to the mitochondrial respiratory chain via the D-lactate dehydrogenase Dld1.
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Affiliation(s)
- Julia Becker-Kettern
- From the Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4367 Belvaux and
| | - Nicole Paczia
- From the Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4367 Belvaux and
| | - Jean-François Conrotte
- From the Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4367 Belvaux and
| | - Daniel P Kay
- From the Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4367 Belvaux and
| | - Cédric Guignard
- the Luxembourg Institute of Science and Technology, 41 Rue du Brill, L-4422 Belvaux, Luxembourg
| | - Paul P Jung
- From the Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4367 Belvaux and
| | - Carole L Linster
- From the Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4367 Belvaux and
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17
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Inhibitory cross-talk upon introduction of a new metabolic pathway into an existing metabolic network. Proc Natl Acad Sci U S A 2012; 109:E2856-64. [PMID: 22984162 DOI: 10.1073/pnas.1208509109] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Evolution or engineering of novel metabolic pathways can endow microbes with new abilities to degrade anthropogenic pollutants or synthesize valuable chemicals. Most studies of the evolution of new pathways have focused on the origins and quality of function of the enzymes involved. However, there is an additional layer of complexity that has received less attention. Introduction of a novel pathway into an existing metabolic network can result in inhibitory cross-talk due to adventitious interactions between metabolites and macromolecules that have not previously encountered one another. Here, we report a thorough examination of inhibitory cross-talk between a novel metabolic pathway for synthesis of pyridoxal 5'-phosphate and the existing metabolic network of Escherichia coli. We demonstrate multiple problematic interactions, including (i) interference by metabolites in the novel pathway with metabolic processes in the existing network, (ii) interference by metabolites in the existing network with the function of the novel pathway, and (iii) diversion of metabolites from the novel pathway by promiscuous activities of enzymes in the existing metabolic network. Identification of the mechanisms of inhibitory cross-talk can reveal the types of adaptations that must occur to enhance the performance of a novel metabolic pathway as well as the fitness of the microbial host. These findings have important implications for evolutionary studies of the emergence of novel pathways in nature as well as genetic engineering of microbes for "green" manufacturing processes.
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18
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Mukherjee T, Hanes J, Tews I, Ealick SE, Begley TP. Pyridoxal phosphate: biosynthesis and catabolism. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:1585-96. [PMID: 21767669 DOI: 10.1016/j.bbapap.2011.06.018] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Revised: 06/26/2011] [Accepted: 06/29/2011] [Indexed: 11/19/2022]
Abstract
Vitamin B(6) is an essential cofactor that participates in a large number of biochemical reactions. Pyridoxal phosphate is biosynthesized de novo by two different pathways (the DXP dependent pathway and the R5P pathway) and can also be salvaged from the environment. It is one of the few cofactors whose catabolic pathway has been comprehensively characterized. It is also known to function as a singlet oxygen scavenger and has protective effects against oxidative stress in fungi. Enzymes utilizing vitamin B(6) are important targets for therapeutic agents. This review provides a concise overview of the mechanistic enzymology of vitamin B(6) biosynthesis and catabolism. This article is part of a Special Issue entitled: Pyridoxal Phosphate Enzymology.
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Affiliation(s)
- Tathagata Mukherjee
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
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19
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Abstract
4-Phospho-D-erythronate is an intermediate in synthesis of pyridoxal 5'-phosphate in some bacteria and an inhibitor of ribose 5-phosphate isomerase. Previous synthetic schemes for the preparation of 4-phospho-D-erythronate required expensive precursors and typically gave low yields. We report a straightforward synthesis of 4-phospho-D-erythronate from the inexpensive precursor D-erythronolactone in 5 steps with a preparatively useful yield of 22%.
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