1
|
Tojo H, Tabeta H, Gunji S, Hirai MY, David P, Javot H, Ferjani A. Roles of type II H +-PPases and PPsPase1/PECP2 in early developmental stages and PPi homeostasis of Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2023; 14:1031426. [PMID: 36778688 PMCID: PMC9911876 DOI: 10.3389/fpls.2023.1031426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 01/09/2023] [Indexed: 06/18/2023]
Abstract
The regulation of intracellular pyrophosphate (PPi) level is crucial for proper morphogenesis across all taxonomic kingdoms. PPi is released as a byproduct from ~200 metabolic reactions, then hydrolyzed by either membrane-bound (H+-PPase) or soluble pyrophosphatases (PPases). In Arabidopsis, the loss of the vacuolar H+-PPase/FUGU5, a key enzyme in PPi homeostasis, results in delayed growth and a number of developmental defects, pointing to the importance of PPi homeostasis in plant morphogenesis. The Arabidopsis genome encodes several PPases in addition to FUGU5, such as PPsPase1/PECP2, VHP2;1 and VHP2;2, although their significance regarding PPi homeostasis remains elusive. Here, to assess their contribution, phenotypic analyses of cotyledon aspect ratio, palisade tissue cellular phenotypes, adaxial side pavement cell complexity, stomatal distribution, and etiolated seedling length were performed, provided that they were altered due to excess PPi in a fugu5 mutant background. Overall, our analyses revealed that the above five traits were unaffected in ppspase1/pecp2, vhp2;1 and vhp2;2 loss-of-function mutants, as well as in fugu5 mutant lines constitutively overexpressing PPsPase1/PECP2. Furthermore, metabolomics revealed that ppspase1/pecp2, vhp2;1 and vhp2;2 etiolated seedlings exhibited metabolic profiles comparable to the wild type. Together, these results indicate that the contribution of PPsPase1/PECP2, VHP2;1 and VHP2;2 to PPi levels is negligible in comparison to FUGU5 in the early stages of seedling development.
Collapse
Affiliation(s)
- Hiroshi Tojo
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
- Department of Biology, Tokyo Gakugei University, Koganei, Tokyo, Japan
| | - Hiromitsu Tabeta
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
- Department of Biology, Tokyo Gakugei University, Koganei, Tokyo, Japan
- RIKEN Center for Sustainable Resource Science, Yokohama, Japan
| | - Shizuka Gunji
- Department of Biology, Tokyo Gakugei University, Koganei, Tokyo, Japan
| | - Masami Y. Hirai
- RIKEN Center for Sustainable Resource Science, Yokohama, Japan
| | - Pascale David
- Aix Marseille Univ, CEA, CNRS, BIAM, Saint Paul-Lez-Durance, France
| | - Hélène Javot
- Aix Marseille Univ, CEA, CNRS, BIAM, Saint Paul-Lez-Durance, France
- Aix Marseille Univ, CEA, CNRS, BIAM, Marseille, France
| | - Ali Ferjani
- Department of Biology, Tokyo Gakugei University, Koganei, Tokyo, Japan
| |
Collapse
|
2
|
Hsieh WY, Wang HM, Chung YH, Lee KT, Liao HS, Hsieh MH. THIAMIN REQUIRING2 is involved in thiamin diphosphate biosynthesis and homeostasis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 111:1383-1396. [PMID: 35791282 DOI: 10.1111/tpj.15895] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 06/28/2022] [Accepted: 07/01/2022] [Indexed: 06/15/2023]
Abstract
The THIAMIN REQUIRING2 (TH2) protein comprising a mitochondrial targeting peptide followed by a transcription enhancement A and a haloacid dehalogenase domain is a thiamin monophosphate (TMP) phosphatase in the vitamin B1 biosynthetic pathway. The Arabidopsis th2-3 T-DNA insertion mutant was chlorotic and deficient in thiamin diphosphate (TDP). Complementation assays confirmed that haloacid dehalogenase domain alone was sufficient to rescue the th2-3 mutant. In pTH2:TH2-GFP/th2-3 complemented plants, the TH2-GFP was localized to the cytosol, mitochondrion, and nucleus, indicating that the vitamin B1 biosynthetic pathway extended across multi-subcellular compartments. Engineered TH2-GFP localized to the cytosol, mitochondrion, nucleus, and chloroplast, could complement the th2 mutant. Together, these results highlight the importance of intracellular TMP and thiamin trafficking in vitamin B1 biosynthesis. In an attempt to enhance the production of thiamin, we created various constructs to overexpress TH2-GFP in the cytosol, mitochondrion, chloroplast, and nucleus. Unexpectedly, overexpressing TH2-GFP resulted in an increase rather than a decrease in TMP. While studies on th2 mutants support TH2 as a TMP phosphatase, analyses of TH2-GFP overexpression lines implicating TH2 may also function as a TDP phosphatase in planta. We propose a working model that the TMP/TDP phosphatase activity of TH2 connects TMP, thiamin, and TDP into a metabolic cycle. The TMP phosphatase activity of TH2 is required for TDP biosynthesis, and the TDP phosphatase activity of TH2 may modulate TDP homeostasis in Arabidopsis.
Collapse
Affiliation(s)
- Wei-Yu Hsieh
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Hsin-Mei Wang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Yi-Hsin Chung
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Kim-Teng Lee
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
- Molecular and Biological Agricultural Sciences, Taiwan International Graduate Program, Academia Sinica, Taipei, 11529, Taiwan
| | - Hong-Sheng Liao
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Ming-Hsiun Hsieh
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
- Molecular and Biological Agricultural Sciences, Taiwan International Graduate Program, Academia Sinica, Taipei, 11529, Taiwan
- Department of Life Sciences, National Central University, Taoyuan, 32001, Taiwan
- Biotechnology Center, National Chung-Hsing University, Taichung, 40227, Taiwan
| |
Collapse
|
3
|
Liu Z, Farkas P, Wang K, Kohli M, Fitzpatrick TB. B vitamin supply in plants and humans: the importance of vitamer homeostasis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 111:662-682. [PMID: 35673947 PMCID: PMC9544542 DOI: 10.1111/tpj.15859] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 06/02/2022] [Accepted: 06/06/2022] [Indexed: 05/26/2023]
Abstract
B vitamins are a group of water-soluble micronutrients that are required in all life forms. With the lack of biosynthetic pathways, humans depend on dietary uptake of these compounds, either directly or indirectly, from plant sources. B vitamins are frequently given little consideration beyond their role as enzyme accessory factors and are assumed not to limit metabolism. However, it should be recognized that each individual B vitamin is a family of compounds (vitamers), the regulation of which has dedicated pathways. Moreover, it is becoming increasingly evident that individual family members have physiological relevance and should not be sidelined. Here, we elaborate on the known forms of vitamins B1 , B6 and B9 , their distinct functions and importance to metabolism, in both human and plant health, and highlight the relevance of vitamer homeostasis. Research on B vitamin metabolism over the past several years indicates that not only the total level of vitamins but also the oft-neglected homeostasis of the various vitamers of each B vitamin is essential to human and plant health. We briefly discuss the potential of plant biology studies in supporting human health regarding these B vitamins as essential micronutrients. Based on the findings of the past few years we conclude that research should focus on the significance of vitamer homeostasis - at the organ, tissue and subcellular levels - which could improve the health of not only humans but also plants, benefiting from cross-disciplinary approaches and novel technologies.
Collapse
Affiliation(s)
- Zeguang Liu
- Vitamins and Environmental Stress Responses in Plants, Department of Botany and Plant BiologyUniversity of GenevaQuai Ernest‐Ansermet 30CH‐1211Geneva 4Switzerland
| | - Peter Farkas
- Vitamins and Environmental Stress Responses in Plants, Department of Botany and Plant BiologyUniversity of GenevaQuai Ernest‐Ansermet 30CH‐1211Geneva 4Switzerland
| | - Kai Wang
- Vitamins and Environmental Stress Responses in Plants, Department of Botany and Plant BiologyUniversity of GenevaQuai Ernest‐Ansermet 30CH‐1211Geneva 4Switzerland
| | - Morgan‐Océane Kohli
- Vitamins and Environmental Stress Responses in Plants, Department of Botany and Plant BiologyUniversity of GenevaQuai Ernest‐Ansermet 30CH‐1211Geneva 4Switzerland
| | - Teresa B. Fitzpatrick
- Vitamins and Environmental Stress Responses in Plants, Department of Botany and Plant BiologyUniversity of GenevaQuai Ernest‐Ansermet 30CH‐1211Geneva 4Switzerland
| |
Collapse
|
4
|
Product inhibition of mammalian thiamine pyrophosphokinase is an important mechanism for maintaining thiamine diphosphate homeostasis. Biochim Biophys Acta Gen Subj 2021; 1866:130071. [PMID: 34942318 DOI: 10.1016/j.bbagen.2021.130071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 12/04/2021] [Accepted: 12/15/2021] [Indexed: 11/20/2022]
Abstract
BACKGROUND Thiamine diphosphate (ThDP), an indispensable cofactor for oxidative energy metabolism, is synthesized through the reaction thiamine + ATP ⇆ ThDP + AMP, catalyzed by thiamine pyrophosphokinase 1 (TPK1), a cytosolic dimeric enzyme. It was claimed that the equilibrium of the reaction is in favor of the formation of thiamine and ATP, at odds with thermodynamic calculations. Here we show that this discrepancy is due to feedback inhibition by the product ThDP. METHODS We used a purified recombinant mouse TPK1 to study reaction kinetics in the forward (physiological) and for the first time also in the reverse direction. RESULTS Keq values reported previously are strongly underestimated, due to the fact the reaction in the forward direction rapidly slows down and reaches a pseudo-equilibrium as ThDP accumulates. We found that ThDP is a potent non-competitive inhibitor (Ki ≈ 0.4 μM) of the forward reaction. In the reverse direction, a true equilibrium is reached with a Keq of about 2 × 10-5, strongly in favor of ThDP formation. In the reverse direction, we found a very low Km for ThDP (0.05 μM), in agreement with a tight binding of ThDP to the enzyme. GENERAL SIGNIFICANCE Inhibition of TPK1 by ThDP explains why intracellular ThDP levels remain low after administration of even very high doses of thiamine. Understanding the consequences of this feedback inhibition is essential for developing reliable methods for measuring TPK activity in tissue extracts and for optimizing the therapeutic use of thiamine and its prodrugs with higher bioavailability under pathological conditions.
Collapse
|
5
|
Joshi J, Mimura M, Suzuki M, Wu S, Gregory JF, Hanson AD, McCarty DR. The Thiamin-Requiring 3 Mutation of Arabidopsis 5-Deoxyxylulose-Phosphate Synthase 1 Highlights How the Thiamin Economy Impacts the Methylerythritol 4-Phosphate Pathway. FRONTIERS IN PLANT SCIENCE 2021; 12:721391. [PMID: 34421975 PMCID: PMC8377734 DOI: 10.3389/fpls.2021.721391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 07/14/2021] [Indexed: 06/01/2023]
Abstract
The thiamin-requiring mutants of Arabidopsis have a storied history as a foundational model for biochemical genetics in plants and have illuminated the central role of thiamin in metabolism. Recent integrative genetic and biochemical analyses of thiamin biosynthesis and utilization imply that leaf metabolism normally operates close to thiamin-limiting conditions. Thus, the mechanisms that allocate thiamin-diphosphate (ThDP) cofactor among the diverse thiamin-dependent enzymes localized in plastids, mitochondria, peroxisomes, and the cytosol comprise an intricate thiamin economy. Here, we show that the classical thiamin-requiring 3 (th3) mutant is a point mutation in plastid localized 5-deoxyxylulose synthase 1 (DXS1), a key regulated enzyme in the methylerythritol 4-phosphate (MEP) isoprene biosynthesis pathway. Substitution of a lysine for a highly conserved glutamate residue (E323) located at the subunit interface of the homodimeric enzyme conditions a hypomorphic phenotype that can be rescued by supplying low concentrations of thiamin in the medium. Analysis of leaf thiamin vitamers showed that supplementing the medium with thiamin increased total ThDP content in both wild type and th3 mutant plants, supporting a hypothesis that the mutant DXS1 enzyme has a reduced affinity for the ThDP cofactor. An unexpected upregulation of a suite of biotic-stress-response genes associated with accumulation of downstream MEP intermediate MEcPP suggests that th3 causes mis-regulation of DXS1 activity in thiamin-supplemented plants. Overall, these results highlight that the central role of ThDP availability in regulation of DXS1 activity and flux through the MEP pathway.
Collapse
Affiliation(s)
- Jaya Joshi
- Department of Horticultural Sciences, University of Florida, Gainesville, FL, United States
| | - Manaki Mimura
- Plant Cytogenetics, Department of Gene Function and Phenomics, National Institute of Genetics, Mishima, Japan
| | - Masaharu Suzuki
- Department of Horticultural Sciences, University of Florida, Gainesville, FL, United States
| | - Shan Wu
- Department of Horticultural Sciences, University of Florida, Gainesville, FL, United States
| | - Jesse F. Gregory
- Department Food Science and Human Nutrition, University of Florida, Gainesville, FL, United States
| | - Andrew D. Hanson
- Department of Horticultural Sciences, University of Florida, Gainesville, FL, United States
| | - Donald R. McCarty
- Department of Horticultural Sciences, University of Florida, Gainesville, FL, United States
| |
Collapse
|
6
|
Tannert M, Balcke GU, Tissier A, Köck M. At4g29530 is a phosphoethanolamine phosphatase homologous to PECP1 with a role in flowering time regulation. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:1072-1083. [PMID: 34098589 DOI: 10.1111/tpj.15367] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 05/28/2021] [Indexed: 05/25/2023]
Abstract
Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) are the most abundant phospholipids in membranes. The biosynthesis of phospholipids occurs mainly via the Kennedy pathway. Recent studies have shown that through this pathway, choline (Cho) moieties are synthesized through the methylation of phosphoethanolamine (PEtn) to phosphocholine (PCho) by phospho-base N-methyltransferase. In Arabidopsis thaliana, the phosphoethanolamine/phosphocholine phosphatase1 (PECP1) is described as an enzyme that regulates the synthesis of PCho by decreasing the PEtn level during phosphate starvation to avoid the energy-consuming methylation step. By homology search, we identified a gene (At4g29530) encoding a putative PECP1 homolog from Arabidopsis with a currently unknown biological function in planta. We found that At4g29530 is not induced by phosphate starvation, and is mainly expressed in leaves and flowers. The analysis of null mutants and overexpression lines revealed that PEtn, rather than PCho, is the substrate in vivo, as in PECP1. Hydrophilic interaction chromatography-coupled mass spectrometry analysis of head group metabolites shows an increased PEtn level and decreased ethanolamine level in null mutants. At4g29530 null mutants have an early flowering phenotype, which is corroborated by a higher PC/PE ratio. Furthermore, we found an increased PCho level. The choline level was not changed, so the results corroborate that the PEtn-dependent pathway is the main route for the generation of Cho moieties. We assume that the PEtn-hydrolyzing enzyme participates in fine-tuning the metabolic pathway, and helps prevent the energy-consuming biosynthesis of PCho through the methylation pathway.
Collapse
Affiliation(s)
- Martin Tannert
- Biocenter, Martin Luther University Halle-Wittenberg, Weinbergweg 22, Halle (Saale), 06120, Germany
| | - Gerd Ulrich Balcke
- Department Cell and Metabolic Biology, Institute of Plant Biochemistry, Weinberg 3, Halle (Saale), 06120, Germany
| | - Alain Tissier
- Department Cell and Metabolic Biology, Institute of Plant Biochemistry, Weinberg 3, Halle (Saale), 06120, Germany
| | - Margret Köck
- Biocenter, Martin Luther University Halle-Wittenberg, Weinbergweg 22, Halle (Saale), 06120, Germany
| |
Collapse
|
7
|
Microbial cell factories for the sustainable manufacturing of B vitamins. Curr Opin Biotechnol 2018; 56:18-29. [PMID: 30138794 DOI: 10.1016/j.copbio.2018.07.006] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Revised: 07/20/2018] [Accepted: 07/23/2018] [Indexed: 12/16/2022]
Abstract
Vitamins are essential compounds in human and animal diets. Their demand is increasing globally in food, feed, cosmetics, chemical and pharmaceutical industries. Most current production methods are unsustainable because they use non-renewable sources and often generate hazardous waste. Many microorganisms produce vitamins naturally, but their corresponding metabolic pathways are tightly regulated since vitamins are needed only in catalytic amounts. Metabolic engineering is accelerating the development of microbial cell factories for vitamins that could compete with chemical methods that have been optimized over decades, but scientific hurdles remain. Additional technological and regulatory issues need to be overcome for innovative bioprocesses to reach the market. Here, we review the current state of development and challenges for fermentative processes for the B vitamin group.
Collapse
|
8
|
Ellens KW, Christian N, Singh C, Satagopam VP, May P, Linster CL. Confronting the catalytic dark matter encoded by sequenced genomes. Nucleic Acids Res 2017; 45:11495-11514. [PMID: 29059321 PMCID: PMC5714238 DOI: 10.1093/nar/gkx937] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 10/03/2017] [Indexed: 01/02/2023] Open
Abstract
The post-genomic era has provided researchers with a deluge of protein sequences. However, a significant fraction of the proteins encoded by sequenced genomes remains without an identified function. Here, we aim at determining how many enzymes of uncertain or unknown function are still present in the Saccharomyces cerevisiae and human proteomes. Using information available in the Swiss-Prot, BRENDA and KEGG databases in combination with a Hidden Markov Model-based method, we estimate that >600 yeast and 2000 human proteins (>30% of their proteins of unknown function) are enzymes whose precise function(s) remain(s) to be determined. This illustrates the impressive scale of the ‘unknown enzyme problem’. We extensively review classical biochemical as well as more recent systematic experimental and computational approaches that can be used to support enzyme function discovery research. Finally, we discuss the possible roles of the elusive catalysts in light of recent developments in the fields of enzymology and metabolism as well as the significance of the unknown enzyme problem in the context of metabolic modeling, metabolic engineering and rare disease research.
Collapse
Affiliation(s)
- Kenneth W Ellens
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Nils Christian
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Charandeep Singh
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Venkata P Satagopam
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Patrick May
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Carole L Linster
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| |
Collapse
|
9
|
Sannino D, Angert ER. Genomic insights into the thiamin metabolism of Paenibacillus thiaminolyticus NRRL B-4156 and P. apiarius NRRL B-23460. Stand Genomic Sci 2017; 12:59. [PMID: 29026451 PMCID: PMC5627462 DOI: 10.1186/s40793-017-0276-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 09/25/2017] [Indexed: 01/01/2023] Open
Abstract
Paenibacillus thiaminolyticus is the model organism for studying thiaminase I, an enigmatic extracellular enzyme. Originally isolated from the feces of clinical patients suffering from thiamin deficiency, P. thiaminolyticus has been implicated in thiamin deficiencies in humans and other animals due to its ability to produce this thiamin-degrading enzyme. Its close relative, P. apiarius, also produces thiaminase I and was originally isolated from dead honeybee larvae, though it has not been reported to be a honeybee pathogen. We generated draft genomes of the type strains of both species, P. thiaminolyticus NRRL B-4156 and P. apiarius NRRL B-23460, to deeply explore potential routes of thiamin metabolism. We discovered that the thiaminase I gene is located in a highly conserved operon with thiamin biosynthesis and salvage genes, as well as genes involved in the biosynthesis of the antibiotic bacimethrin. Based on metabolic pathway predictions, P. apiarius NRRL B-23460 has the genomic capacity to synthesize thiamin de novo using a pathway that is rarely seen in bacteria, but P. thiaminolyticus NRRL B-4156 is a thiamin auxotroph. Both genomes encode importers for thiamin and the pyrimidine moiety of thiamin, as well as enzymes to synthesize thiamin from pyrimidine and thiazole.
Collapse
|
10
|
Hsieh WY, Liao JC, Wang HT, Hung TH, Tseng CC, Chung TY, Hsieh MH. The Arabidopsis thiamin-deficient mutant pale green1 lacks thiamin monophosphate phosphatase of the vitamin B 1 biosynthesis pathway. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 91:145-157. [PMID: 28346710 DOI: 10.1111/tpj.13552] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 03/20/2017] [Accepted: 03/21/2017] [Indexed: 05/24/2023]
Abstract
Thiamin diphosphate (TPP, vitamin B1 ) is an essential coenzyme present in all organisms. Animals obtain TPP from their diets, but plants synthesize TPPde novo. We isolated and characterized an Arabidopsis pale green1 (pale1) mutant that contained higher concentrations of thiamin monophosphate (TMP) and less thiamin and TPP than the wild type. Supplementation with thiamin, but not the thiazole and pyrimidine precursors, rescued the mutant phenotype, indicating that the pale1 mutant is a thiamin-deficient mutant. Map-based cloning and whole-genome sequencing revealed that the pale1 mutant has a mutation in At5g32470 encoding a TMP phosphatase of the TPP biosynthesis pathway. We further confirmed that the mutation of At5g32470 is responsible for the mutant phenotypes by complementing the pale1 mutant with constructs overexpressing full-length At5g32470. Most plant TPP biosynthetic enzymes are located in the chloroplasts and cytosol, but At5g32470-GFP localized to the mitochondrion of the root, hypocotyl, mesophyll and guard cells of the 35S:At5g32470-GFP complemented plants. The subcellular localization of a functional TMP phosphatase suggests that the complete vitamin B1 biosynthesis pathway may involve the chloroplasts, mitochondria and cytosol in plants. Analysis of PALE1 promoter-uidA activity revealed that PALE1 is mainly expressed in vascular tissues of Arabidopsis seedlings. Quantitative RT-PCR analysis of TPP biosynthesis genes and genes encoding the TPP-dependent enzymes pyruvate dehydrogenase, α-ketoglutarate dehydrogenase and transketolase revealed that the transcript levels of these genes were upregulated in the pale1 mutant. These results suggest that endogenous levels of TPP may affect the expression of genes involved in TPP biosynthesis and TPP-dependent enzymes.
Collapse
Affiliation(s)
- Wei-Yu Hsieh
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Jo-Chien Liao
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Hsin-Tzu Wang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Tzu-Huan Hung
- Biotechnology Division, Taiwan Agricultural Research Institute, Taichung, 41362, Taiwan
| | - Ching-Chih Tseng
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Tsui-Yun Chung
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Ming-Hsiun Hsieh
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529, Taiwan
| |
Collapse
|
11
|
Mangel N, Fudge JB, Fitzpatrick TB, Gruissem W, Vanderschuren H. Vitamin B1 diversity and characterization of biosynthesis genes in cassava. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:3351-3363. [PMID: 28859374 PMCID: PMC5853225 DOI: 10.1093/jxb/erx196] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Accepted: 05/22/2017] [Indexed: 05/06/2023]
Abstract
Vitamin B1, which consists of the vitamers thiamin and its phosphorylated derivatives, is an essential micronutrient for all living organisms because it is required as a metabolic cofactor in several enzymatic reactions. Genetic diversity of vitamin B1 biosynthesis and accumulation has not been investigated in major crop species other than rice and potato. We analyzed cassava germplasm for accumulation of B1 vitamers. Vitamin B1 content in leaves and roots of 41 cassava accessions showed significant variation between accessions. HPLC analyses of B1 vitamers revealed distinct profiles in cassava leaves and storage roots, with nearly equal relative levels of thiamin pyrophosphate and thiamin monophosphate in leaves, but mostly thiamin pyrophosphate in storage roots. Unusually, the cassava genome has two genes encoding the 4-amino-2-methyl-5-hydroxymethylpyrimidine phosphate synthase, THIC (MeTHIC1 and MeTHIC2), both of which carry a riboswitch in the 3'-UTR, as well as the adenylated thiazole synthase, THI1 (MeTHI1a and MeTHI1b). The THIC and THI1 genes are expressed at very low levels in storage roots compared with the accumulation of vitamin B1, indicating only limited biosynthesis de novo therein. In leaves, vitamin B1 content is negatively correlated with THIC and THI1 expression levels, suggesting post-transcriptional regulation of THIC by the riboswitch present in the 3'-UTR of the THIC mRNA and regulation of THI1 by promoter activity or alternative post-transcriptional mechanisms.
Collapse
Affiliation(s)
| | - Jared B Fudge
- Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Teresa B Fitzpatrick
- Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | | | - Hervé Vanderschuren
- Department of Biology, ETH Zurich, Zurich, Switzerland
- AgroBioChem Department, Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| |
Collapse
|
12
|
Bunik V, Aleshin V. Analysis of the Protein Binding Sites for Thiamin and Its Derivatives to Elucidate the Molecular Mechanisms of the Noncoenzyme Action of Thiamin (Vitamin B1). STUDIES IN NATURAL PRODUCTS CHEMISTRY 2017. [DOI: 10.1016/b978-0-444-63930-1.00011-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
13
|
Sa N, Rawat R, Thornburg C, Walker KD, Roje S. Identification and characterization of the missing phosphatase on the riboflavin biosynthesis pathway in Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 88:705-716. [PMID: 27490826 DOI: 10.1111/tpj.13291] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 07/22/2016] [Accepted: 07/25/2016] [Indexed: 06/06/2023]
Abstract
Despite the importance of riboflavin as the direct precursor of the cofactors flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN), the physiologically relevant catalyst dephosphorylating the riboflavin biosynthesis pathway intermediate 5-amino-6-ribitylamino-2,4(1H,3H) pyrimidinedione 5'-phosphate (ARPP) has not been characterized from any organism. By using as the query sequence a previously identified plastidial FMN hydrolase AtcpFHy1 (At1g79790), belonging to the haloacid dehalogenase (HAD) superfamily, seven candidates for the missing ARPP phosphatase were found, cloned, recombinantly expressed, and purified. Activity screening showed that the enzymes encoded by AtcpFHy1, At4g11570, and At4g25840 catalyze dephosphorylation of ARPP. AtcpFHy1 was renamed AtcpFHy/PyrP1, At4g11570 and At4g25840 were named AtPyrP2 and AtGpp1/PyrP3, respectively. Subcellular localization in planta indicated that AtPyrP2 was localized in plastids and AtGpp1/PyrP3 in mitochondria. Biochemical characterization of AtcpFHy/PyrP1 and AtPyrP2 showed that they have similar Km values for the substrate ARPP, with AtcpFHy/PyrP1 having higher catalytic efficiency. Screening of 21 phosphorylated substrates showed that AtPyrP2 is specific for ARPP. Molecular weights of AtcpFHy/PyrP1 and AtPyrP2 were estimated at 46 and 72 kDa, suggesting dimers. pH and temperature optima for AtcpFHy/PyrP1 and AtPyrP2 were ~7.0-8.5 and 40-50°C. T-DNA knockout of AtcpFHy/PyrP1 did not affect the flavin profile of the transgenic plants, whereas silencing of AtPyrP2 decreased accumulation of riboflavin, FMN, and FAD. Our results strongly support AtPyrP2 as the missing phosphatase on the riboflavin biosynthesis pathway in Arabidopsis thaliana. The identification of this enzyme closes a long-standing gap in understanding of the riboflavin biosynthesis in plants.
Collapse
Affiliation(s)
- Na Sa
- Institute of Biological Chemistry, Washington State University, Pullman, WA, 99164, USA
| | - Renu Rawat
- Institute of Biological Chemistry, Washington State University, Pullman, WA, 99164, USA
| | - Chelsea Thornburg
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Kevin D Walker
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Sanja Roje
- Institute of Biological Chemistry, Washington State University, Pullman, WA, 99164, USA
| |
Collapse
|
14
|
Baier F, Copp JN, Tokuriki N. Evolution of Enzyme Superfamilies: Comprehensive Exploration of Sequence–Function Relationships. Biochemistry 2016; 55:6375-6388. [DOI: 10.1021/acs.biochem.6b00723] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- F. Baier
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - J. N. Copp
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - N. Tokuriki
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| |
Collapse
|
15
|
Goyer A. Thiamin biofortification of crops. Curr Opin Biotechnol 2016; 44:1-7. [PMID: 27750185 DOI: 10.1016/j.copbio.2016.09.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 09/08/2016] [Accepted: 09/14/2016] [Indexed: 12/25/2022]
Abstract
Thiamin is essential for human health. While plants are the ultimate source of thiamin in most human diets, staple foods like white rice have low thiamin content. Therefore, populations whose diets are mainly based on low-thiamin staple crops suffer from thiamin deficiency. Biofortification of rice grain by engineering the thiamin biosynthesis pathway has recently been attempted, with up to 5-fold increase in thiamin content in unpolished seeds. However, polished seeds that retain only the starchy endosperm had similar thiamin content than that of non-engineered plants. Various factors such as limited supply of precursors, limited activity of thiamin biosynthetic enzymes, dependence on maternal tissues to supply thiamin, or lack of thiamin stabilizing proteins may have hindered thiamin increase in the endosperm.
Collapse
Affiliation(s)
- Aymeric Goyer
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97330, United States; Hermiston Agricultural Research and Extension Center, Oregon State University, Hermiston, OR 97838, United States.
| |
Collapse
|
16
|
Storari M, Kulli S, Wüthrich D, Bruggmann R, Berthoud H, Arias-Roth E. Genomic approach to studying nutritional requirements of Clostridium tyrobutyricum and other Clostridia causing late blowing defects. Food Microbiol 2016; 59:213-23. [PMID: 27375262 DOI: 10.1016/j.fm.2016.05.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 04/29/2016] [Accepted: 05/23/2016] [Indexed: 11/16/2022]
Abstract
Clostridium tyrobutyricum is the main microorganism responsible for the late blowing defect in hard and semi-hard cheeses, causing considerable economic losses to the cheese industry. Deeper knowledge of the metabolic requirements of this microorganism can lead to the development of more effective control approaches. In this work, the amino acids and B vitamins essential for sustaining the growth of C. tyrobutyricum were investigated using a genomic approach. As the first step, the genomes of four C. tyrobutyricum strains were analyzed for the presence of genes putatively involved in the biosynthesis of amino acids and B vitamins. Metabolic pathways could be reconstructed for all amino acids and B vitamins with the exception of biotin (vitamin B7) and folate (vitamin B9). The biotin pathway was missing the enzyme amino-7-oxononanoate synthase that catalyzes the condensation of pimeloyl-ACP and l-alanine to 8-amino-7-oxononanoate. In the folate pathway, the missing genes were those coding for para-aminobenzoate synthase and aminodeoxychorismate lyase enzymes. These enzymes are responsible for the conversion of chorismate into para-aminobenzoate (PABA). Two C. tyrobutyircum strains whose genome was analyzed in silico as well as other 10 strains isolated from cheese were tested in liquid media to confirm these observations. 11 strains showed growth in a defined liquid medium containing biotin and PABA after 6-8 days of incubation. No strain showed growth when only one or none of these compounds were added, confirming the observations obtained in silico. Furthermore, the genome analysis was extended to genomes of single strains of other Clostridium species potentially causing late blowing, namely Clostridium beijerinckii, Clostridium sporogenes and Clostridium butyricum. Only the biotin biosynthesis pathway was incomplete for C. butyricum and C. beijerincki. In contrast, C. sporogenes showed missing enzymes in biosynthesis pathways of several amino acids as well as biotin, folate, and cobalamin (vitamin B12). These observations agree with the results of growth experiments of these species in liquid media reported in the literature. The results of this study suggest that biotin and folate are potential targets for reducing late blowing in cheese and highlight the usefulness of genomic analysis for identifying essential nutrients in bacteria.
Collapse
Affiliation(s)
| | - Sandra Kulli
- Institute for Food Sciences, Agroscope, Bern, Switzerland
| | - Daniel Wüthrich
- Interfaculty Bioinformatics Unit and Swiss Institute of Bioinformatics, University of Bern, Bern, Switzerland
| | - Rémy Bruggmann
- Interfaculty Bioinformatics Unit and Swiss Institute of Bioinformatics, University of Bern, Bern, Switzerland
| | | | | |
Collapse
|
17
|
Henry CS, Lerma-Ortiz C, Gerdes SY, Mullen JD, Colasanti R, Zhukov A, Frelin O, Thiaville JJ, Zallot R, Niehaus TD, Hasnain G, Conrad N, Hanson AD, de Crécy-Lagard V. Systematic identification and analysis of frequent gene fusion events in metabolic pathways. BMC Genomics 2016; 17:473. [PMID: 27342196 PMCID: PMC4921024 DOI: 10.1186/s12864-016-2782-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 05/26/2016] [Indexed: 11/19/2022] Open
Abstract
Background Gene fusions are the most powerful type of in silico-derived functional associations. However, many fusion compilations were made when <100 genomes were available, and algorithms for identifying fusions need updating to handle the current avalanche of sequenced genomes. The availability of a large fusion dataset would help probe functional associations and enable systematic analysis of where and why fusion events occur. Results Here we present a systematic analysis of fusions in prokaryotes. We manually generated two training sets: (i) 121 fusions in the model organism Escherichia coli; (ii) 131 fusions found in B vitamin metabolism. These sets were used to develop a fusion prediction algorithm that captured the training set fusions with only 7 % false negatives and 50 % false positives, a substantial improvement over existing approaches. This algorithm was then applied to identify 3.8 million potential fusions across 11,473 genomes. The results of the analysis are available in a searchable database at http://modelseed.org/projects/fusions/. A functional analysis identified 3,000 reactions associated with frequent fusion events and revealed areas of metabolism where fusions are particularly prevalent. Conclusions Customary definitions of fusions were shown to be ambiguous, and a stricter one was proposed. Exploring the genes participating in fusion events showed that they most commonly encode transporters, regulators, and metabolic enzymes. The major rationales for fusions between metabolic genes appear to be overcoming pathway bottlenecks, avoiding toxicity, controlling competing pathways, and facilitating expression and assembly of protein complexes. Finally, our fusion dataset provides powerful clues to decipher the biological activities of domains of unknown function. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2782-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Christopher S Henry
- Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA. .,Computation Institute, The University of Chicago, Chicago, IL, 60637, USA.
| | - Claudia Lerma-Ortiz
- Microbiology and Cell Science Department, University of Florida, Gainesville, FL, 32611, USA
| | - Svetlana Y Gerdes
- Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA.,Microbiology and Cell Science Department, University of Florida, Gainesville, FL, 32611, USA
| | - Jeffrey D Mullen
- Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Ric Colasanti
- Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Aleksey Zhukov
- Microbiology and Cell Science Department, University of Florida, Gainesville, FL, 32611, USA
| | - Océane Frelin
- Horticultural Sciences Department, University of Florida, Gainesville, FL, 32611, USA
| | - Jennifer J Thiaville
- Microbiology and Cell Science Department, University of Florida, Gainesville, FL, 32611, USA
| | - Rémi Zallot
- Microbiology and Cell Science Department, University of Florida, Gainesville, FL, 32611, USA
| | - Thomas D Niehaus
- Horticultural Sciences Department, University of Florida, Gainesville, FL, 32611, USA
| | - Ghulam Hasnain
- Horticultural Sciences Department, University of Florida, Gainesville, FL, 32611, USA
| | - Neal Conrad
- Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Andrew D Hanson
- Horticultural Sciences Department, University of Florida, Gainesville, FL, 32611, USA
| | - Valérie de Crécy-Lagard
- Microbiology and Cell Science Department, University of Florida, Gainesville, FL, 32611, USA.
| |
Collapse
|
18
|
Dong W, Thomas N, Ronald PC, Goyer A. Overexpression of Thiamin Biosynthesis Genes in Rice Increases Leaf and Unpolished Grain Thiamin Content But Not Resistance to Xanthomonas oryzae pv. oryzae. FRONTIERS IN PLANT SCIENCE 2016; 7:616. [PMID: 27242822 PMCID: PMC4861732 DOI: 10.3389/fpls.2016.00616] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 04/22/2016] [Indexed: 05/06/2023]
Abstract
Thiamin diphosphate (ThDP), also known as vitamin B1, serves as an enzymatic cofactor in glucose metabolism, the Krebs cycle, and branched-chain amino acid biosynthesis in all living organisms. Unlike plants and microorganisms, humans are not able to synthesize ThDP de novo and must obtain it from their diet. Staple crops such as rice are poor sources of thiamin. Hence, populations that mainly consume rice commonly suffer thiamin deficiency. In addition to thiamin's nutritional function, studies in rice have shown that some thiamin biosynthesis genes are involved in resistance to Xanthomonas oryzae, which causes a serious disease in rice fields. This study shows that overexpression of two thiamin biosynthesis genes, 4-methyl-5-β-hydroxyethylthiazole phosphate synthase and 4-amino-2-methyl-5-hydroxymethylpyrimidine phosphate synthase, involved in the first steps of the thiazole and pyrimidine synthesis branches, respectively, increased thiamin content up to fivefold in unpolished seeds that retain the bran. However, thiamin levels in polished seeds with removed bran were similar to those found in polished control seeds. Plants with higher accumulation of thiamin did not show enhanced resistance to X. oryzae. These results indicate that stacking of two traits can enhance thiamin accumulation in rice unpolished grain. We discuss potential roadblocks that prevent thiamin accumulation in the endosperm.
Collapse
Affiliation(s)
- Wei Dong
- Department of Botany and Plant Pathology, Oregon State UniversityCorvallis, OR, USA
- Hermiston Agricultural Research and Extension Center, Oregon State UniversityHermiston, OR, USA
| | - Nicholas Thomas
- Department of Plant Pathology, University of California, DavisDavis, CA, USA
| | - Pamela C. Ronald
- Department of Plant Pathology, University of California, DavisDavis, CA, USA
| | - Aymeric Goyer
- Department of Botany and Plant Pathology, Oregon State UniversityCorvallis, OR, USA
- Hermiston Agricultural Research and Extension Center, Oregon State UniversityHermiston, OR, USA
- *Correspondence: Aymeric Goyer,
| |
Collapse
|