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Hemasa A, Spry C, Mack M, Saliba KJ. Mutation of the Plasmodium falciparum Flavokinase Confers Resistance to Roseoflavin and 8-Aminoriboflavin. ACS Infect Dis 2024; 10:2939-2949. [PMID: 38920250 DOI: 10.1021/acsinfecdis.4c00289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2024]
Abstract
The riboflavin analogues, roseoflavin and 8-aminoriboflavin, inhibit malaria parasite proliferation by targeting riboflavin utilization. To determine their mechanism of action, we generated roseoflavin-resistant parasites by in vitro evolution. Relative to wild-type, these parasites were 4-fold resistant to roseoflavin and cross-resistant to 8-aminoriboflavin. Whole genome sequencing of the resistant parasites revealed a missense mutation leading to an amino acid change (L672H) in the gene coding for a putative flavokinase (PfFK), the enzyme responsible for converting riboflavin into the cofactor flavin mononucleotide (FMN). To confirm that the L672H mutation is responsible for the phenotype, we generated parasites with the missense mutation incorporated into the PfFK gene. The IC50 values for roseoflavin and 8-aminoriboflavin against the roseoflavin-resistant parasites created through in vitro evolution were indistinguishable from those against parasites in which the missense mutation was introduced into the native PfFK. We also generated two parasite lines episomally expressing GFP-tagged versions of either the wild-type or mutant forms of PfFK. We found that PfFK-GFP localizes to the parasite cytosol and that immunopurified PfFK-GFP phosphorylated riboflavin, roseoflavin, and 8-aminoriboflavin. The L672H mutation increased the KM for roseoflavin, explaining the resistance phenotype. Mutant PfFK is no longer capable of phosphorylating 8-aminoriboflavin, but its antiplasmodial activity against resistant parasites can still be antagonized by increasing the extracellular concentration of riboflavin, consistent with it also inhibiting parasite growth through competitive inhibition of PfFK. Our findings, therefore, are consistent with roseoflavin and 8-aminoriboflavin inhibiting parasite proliferation by inhibiting riboflavin phosphorylation and via the generation of toxic flavin cofactor analogues.
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Affiliation(s)
- Ayman Hemasa
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Christina Spry
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Matthias Mack
- Institute for Technical Microbiology, Department of Biotechnology, Mannheim University of Applied Sciences, Mannheim 68163, Germany
| | - Kevin J Saliba
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
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2
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Yuzon JD, Schultzhaus Z, Wang Z. Transcriptomic and genomic effects of gamma-radiation exposure on strains of the black yeast Exophiala dermatitidis evolved to display increased ionizing radiation resistance. Microbiol Spectr 2023; 11:e0221923. [PMID: 37676019 PMCID: PMC10581076 DOI: 10.1128/spectrum.02219-23] [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: 05/25/2023] [Accepted: 07/15/2023] [Indexed: 09/08/2023] Open
Abstract
IMPORTANCE Ionizing radiation poses a significant threat to living organisms and human health, given its destructive nature and widespread use in fields such as medicine and the potential for nuclear disasters. Melanized fungi exhibit remarkable survival capabilities, enduring doses up to 1,000-fold higher than mammals. Through adaptive laboratory evolution, we validated the protective role of constitutive upregulation of DNA repair genes in the black yeast Exophiala dermatitidis, enhancing survival after radiation exposure. Surprisingly, we found that evolved strains lacking melanin still achieved high levels of radioresistance. Our study unveiled the significance of robust activation and enhancement of redox homeostasis, as evidenced by the profound transcriptional changes and increased accumulation of mutations, in substantially improving ionizing radiation resistance in the absence of melanin. These findings underscore the delicate balance between DNA repair and redox homeostasis for an organism's ability to endure and recover from radiation exposure.
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Affiliation(s)
- Jennifer D. Yuzon
- National Research Council Postdoctoral Research Associate, US Naval Research Laboratory, Washington, USA
| | - Zachary Schultzhaus
- Center for Bio/Molecular Science and Engineering, US Naval Research Laboratory, Washington, USA
| | - Zheng Wang
- Center for Bio/Molecular Science and Engineering, US Naval Research Laboratory, Washington, USA
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3
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da Fonseca-Pereira P, Monteiro-Batista RDC, Araújo WL, Nunes-Nesi A. Harnessing enzyme cofactors and plant metabolism: an essential partnership. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 114:1014-1036. [PMID: 36861364 DOI: 10.1111/tpj.16167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 02/18/2023] [Accepted: 02/25/2023] [Indexed: 05/31/2023]
Abstract
Cofactors are fundamental to the catalytic activity of enzymes. Additionally, because plants are a critical source of several cofactors (i.e., including their vitamin precursors) within the context of human nutrition, there have been several studies aiming to understand the metabolism of coenzymes and vitamins in plants in detail. For example, compelling evidence has been brought forth regarding the role of cofactors in plants; specifically, it is becoming increasingly clear that an adequate supply of cofactors in plants directly affects their development, metabolism, and stress responses. Here, we review the state-of-the-art knowledge on the significance of coenzymes and their precursors with regard to general plant physiology and discuss the emerging functions attributed to them. Furthermore, we discuss how our understanding of the complex relationship between cofactors and plant metabolism can be used for crop improvement.
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Affiliation(s)
- Paula da Fonseca-Pereira
- National Institute of Science and Technology on Plant Physiology under Stress Conditions, Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Rita de Cássia Monteiro-Batista
- National Institute of Science and Technology on Plant Physiology under Stress Conditions, Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Wagner L Araújo
- National Institute of Science and Technology on Plant Physiology under Stress Conditions, Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
| | - Adriano Nunes-Nesi
- National Institute of Science and Technology on Plant Physiology under Stress Conditions, Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, Minas Gerais, Brazil
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4
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Kwon S. Structural Insight into the Working Mechanism of the FAD Synthetase from the Human Pathogen Streptococcus pneumoniae: A Molecular Docking Simulation Study. Int J Mol Sci 2023; 24:ijms24043121. [PMID: 36834532 PMCID: PMC9962085 DOI: 10.3390/ijms24043121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/29/2023] [Accepted: 02/01/2023] [Indexed: 02/08/2023] Open
Abstract
Flavin adenine dinucleotide synthetases (FADSs) catalyze FAD biosynthesis through two consecutive catalytic reactions, riboflavin (RF) phosphorylation and flavin mononucleotide (FMN) adenylylation. Bacterial FADSs have RF kinase (RFK) and FMN adenylyltransferase (FMNAT) domains, whereas the two domains are separated into two independent enzymes in human FADSs. Bacterial FADSs have attracted considerable attention as drug targets due to the fact that they differ from human FADSs in structure and domain combinations. In this study, we analyzed the putative FADS structure from the human pathogen Streptococcus pneumoniae (SpFADS) determined by Kim et al., including conformational changes of key loops in the RFK domain upon substrate binding. Structural analysis and comparisons with a homologous FADS structure revealed that SpFADS corresponds to a hybrid between open and closed conformations of the key loops. Surface analysis of SpFADS further revealed its unique biophysical properties for substrate attraction. In addition, our molecular docking simulations predicted possible substrate-binding modes at the active sites of the RFK and FMNAT domains. Our results provide a structural basis to understand the catalytic mechanism of SpFADS and develop novel SpFADS inhibitors.
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Affiliation(s)
- Sunghark Kwon
- Department of Biotechnology, Konkuk University, Chungju 27478, Chungbuk, Republic of Korea;
- Research Institute for Biomedical & Health Science, Konkuk University, Chungju 27478, Chungbuk, Republic of Korea
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5
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Lynch JH, Roje S. A higher plant FAD synthetase is fused to an inactivated FAD pyrophosphatase. J Biol Chem 2022; 298:102626. [PMID: 36273586 PMCID: PMC9678776 DOI: 10.1016/j.jbc.2022.102626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 10/16/2022] [Accepted: 10/17/2022] [Indexed: 11/05/2022] Open
Abstract
The riboflavin derivatives FMN and flavin adenine dinucleotide (FAD) are critical cofactors for wide-ranging biological processes across all kingdoms of life. Although it is well established that these flavins can be readily interconverted, in plants, the responsible catalysts and regulatory mechanisms remain poorly understood. Here, we report the cloning and biochemical characterization of an FAD synthetase encoded by the gene At5g03430, which we have designated AtFADS1 (A. thaliana FADS1). The catalytic properties of the FAD synthetase activity are similar to those reported for other FAD synthetases, except that we observed maximum activity with Zn2+ as the associated divalent metal cation. Like human FAD synthetase, AtFADS1 exists as an apparent fusion with an ancestral FAD pyrophosphatase, a feature that is conserved across plants. However, we detected no pyrophosphatase activity with AtFADS1, consistent with an observed loss of a key catalytic residue in higher plant evolutionary history. In contrast, we determined that algal FADS1 retains both FAD synthetase and pyrophosphatase activity. We discuss the implications, including the potential for yet-unstudied biologically relevant noncatalytic functions, and possible evolutionary pressures that have led to the loss of FAD pyrophosphatase activity, yet universal retention of an apparently nonfunctional domain in FADS of land plants.
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Affiliation(s)
- Joseph H Lynch
- Institute of Biological Chemistry, Washington State University, Pullman, Washington, USA
| | - Sanja Roje
- Institute of Biological Chemistry, Washington State University, Pullman, Washington, USA.
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Arib C, Liu H, Liu Q, Cieutat AM, Paleni D, Li X, Spadavecchia J. Flavin Adenine Dinucleotide (FAD) Pegylated (PEG)-Complexes: Proof of Concept (PoC) of theranostic tool on a Murine Breast Cancer Model. Nanotheranostics 2022; 6:175-183. [PMID: 34976592 PMCID: PMC8671949 DOI: 10.7150/ntno.63496] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 08/08/2021] [Indexed: 01/10/2023] Open
Abstract
Flavin adenine dinucleotide (FAD) plays a key role in an extensive range of cellular oxidation-reduction reactions, which is engaged in metabolic pathways. The purpose of this study was to realize pegylated flavins formulation, named FAD and FAD-PEG diacid complex as theranostic tool in cancer therapy. For this objective, a murine breast cancer model, which was induced by mouse-derived4T1 breast cancer cells was studied to assess the therapeutic efficacy of FAD (named NP1) and FAD-PEG diacid complex (named NP2). The cytokines were monitored to evaluate the serum inflammatory factors to develop the blood cell content of different groups of nude mice. The experimental model shows that an intravenous injection of FAD (NP1) can significantly reduce tumour volume, tumour index and thymus index, and decrease neutrophils (NE), monocytes (MO), eosinophils (EO), and basophils (BA). At the same time, the content of IL-1α, IL-12P70, TNF α, IL-1β and IL-6 was significantly reduced, and the content of IL-10 was significantly increased. These results provide the proof-of-concept for FAD as a smart adjuvant for cancer therapy and encourages their further development in the field of Nanomedicine.
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Affiliation(s)
- Celia Arib
- CNRS, UMR 7244, NBD-CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Sorbonne Paris Nord, campus Bobigny, France
| | - Hui Liu
- Department of Hepatobiliary Surgery, Guangdong Provincial Key Laboratory of Regional Immunity and Diseases & Carson International Cancer Center, Shenzhen University General Hospital & Shenzhen University Clinical Medical Academy Center, Shenzhen University, Shenzhen, China
| | - Qiqian Liu
- CNRS, UMR 7244, NBD-CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Sorbonne Paris Nord, campus Bobigny, France
| | - Anne-Marie Cieutat
- CNRS, UMR 7244, NBD-CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Sorbonne Paris Nord, campus Bobigny, France
| | - Didier Paleni
- BioEVEN start-up, 75 rue de Lourmel 75015 Paris, France
| | - Xiaowu Li
- Department of Hepatobiliary Surgery, Guangdong Provincial Key Laboratory of Regional Immunity and Diseases & Carson International Cancer Center, Shenzhen University General Hospital & Shenzhen University Clinical Medical Academy Center, Shenzhen University, Shenzhen, China
| | - Jolanda Spadavecchia
- CNRS, UMR 7244, NBD-CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Sorbonne Paris Nord, campus Bobigny, France.,Department of Hepatobiliary Surgery, Guangdong Provincial Key Laboratory of Regional Immunity and Diseases & Carson International Cancer Center, Shenzhen University General Hospital & Shenzhen University Clinical Medical Academy Center, Shenzhen University, Shenzhen, China
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7
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Bruni F, Giancaspero TA, Oreb M, Tolomeo M, Leone P, Boles E, Roberti M, Caselle M, Barile M. Subcellular Localization of Fad1p in Saccharomyces cerevisiae: A Choice at Post-Transcriptional Level? Life (Basel) 2021; 11:967. [PMID: 34575116 PMCID: PMC8470081 DOI: 10.3390/life11090967] [Citation(s) in RCA: 2] [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: 07/29/2021] [Revised: 09/06/2021] [Accepted: 09/13/2021] [Indexed: 11/24/2022] Open
Abstract
FAD synthase is the last enzyme in the pathway that converts riboflavin into FAD. In Saccharomyces cerevisiae, the gene encoding for FAD synthase is FAD1, from which a sole protein product (Fad1p) is expected to be generated. In this work, we showed that a natural Fad1p exists in yeast mitochondria and that, in its recombinant form, the protein is able, per se, to both enter mitochondria and to be destined to cytosol. Thus, we propose that FAD1 generates two echoforms-that is, two identical proteins addressed to different subcellular compartments. To shed light on the mechanism underlying the subcellular destination of Fad1p, the 3' region of FAD1 mRNA was analyzed by 3'RACE experiments, which revealed the existence of (at least) two FAD1 transcripts with different 3'UTRs, the short one being 128 bp and the long one being 759 bp. Bioinformatic analysis on these 3'UTRs allowed us to predict the existence of a cis-acting mitochondrial localization motif, present in both the transcripts and, presumably, involved in protein targeting based on the 3'UTR context. Here, we propose that the long FAD1 transcript might be responsible for the generation of mitochondrial Fad1p echoform.
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Affiliation(s)
- Francesco Bruni
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
| | - Teresa Anna Giancaspero
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
| | - Mislav Oreb
- Institute of Molecular Biosciences, Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany; (M.O.); (E.B.)
| | - Maria Tolomeo
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
| | - Piero Leone
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
| | - Eckhard Boles
- Institute of Molecular Biosciences, Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany; (M.O.); (E.B.)
| | - Marina Roberti
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
| | - Michele Caselle
- Physics Department, University of Turin and INFN, Via P. Giuria 1, 10125 Turin, Italy;
| | - Maria Barile
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari Aldo Moro, Via Orabona 4, 70125 Bari, Italy; (F.B.); (T.A.G.); (M.T.); (P.L.); (M.R.)
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8
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Alteration of Flavin Cofactor Homeostasis in Human Neuromuscular Pathologies. Methods Mol Biol 2021; 2280:275-295. [PMID: 33751442 DOI: 10.1007/978-1-0716-1286-6_18] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The aim of this short review chapter is to provide a brief summary of the relevance of riboflavin (Rf or vitamin B2) and its derived cofactors flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) for human neuromuscular bioenergetics.Therefore, as a completion of this book we would like to summarize what kind of human pathologies could derive from genetic disturbances of Rf transport, flavin cofactor synthesis and delivery to nascent apoflavoproteins, as well as by alteration of vitamin recycling during protein turnover.
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Arib C, Liu H, Liu Q, Cieutat AM, Paleni D, Li X, Spadavecchia J. A Pegylated Flavin Adenine Dinucleotide PEG Complex to Boost Immunogenic and Therapeutic Effects in a Liver Cancer Model. Nanotheranostics 2021; 5:405-416. [PMID: 33912380 PMCID: PMC8077970 DOI: 10.7150/ntno.59290] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 04/03/2021] [Indexed: 01/10/2023] Open
Abstract
Flavin adenine dinucleotide (FAD) is engaged in several metabolic diseases. Its main role is being a cofactor essential for the activity of many flavoproteins, which play a crucial role in electron transport pathways in living systems. The aim of this study was to apply a pegylated flavins formulation named FAD-PEG diacide complex as theranostic pathway in cancer therapy. For this purpose, a mouse liver cancer model induced by Hepa1-6 cells was used to evaluate the therapeutic efficacy of FAD (named NP1) and FAD-PEG diacide complex (named NP2). The cytokines were applied to screen the serum inflammatory factors, to establish the blood cell content of different groups of nude mice. The highlights follows that FAD formulations (NP1; NP2) significantly suppressed the tumor growth and reduced the tumor index without effects on the body weight of mice. Furthermore, NP2 significantly reduced the serum levels of cytokines IL-6, TNF-α and IL-12 (P70). The reported results provide the proof-of-concept for the synthesis of a smart adjuvant for liver cancer therapy and support their further development in the field of nanomedicine.
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Affiliation(s)
- Celia Arib
- CNRS, UMR 7244, NBD-CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Paris 13, Sorbonne Paris Nord, Bobigny, France
| | - Hui Liu
- Department of Hepatobiliary Surgery, Guangdong Provincial Key Laboratory of Regional Immunity and Diseases & Carson International Cancer Center, Shenzhen University General Hospital & Shenzhen University Clinical Medical Academy Center, Shenzhen University, Shenzhen, China
| | - Qiqian Liu
- CNRS, UMR 7244, NBD-CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Paris 13, Sorbonne Paris Nord, Bobigny, France
| | - Anne-Marie Cieutat
- CNRS, UMR 7244, NBD-CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Paris 13, Sorbonne Paris Nord, Bobigny, France
| | - Didier Paleni
- BioEVEN start-up, 75 rue de Lourmel 75015 Paris, France
| | - Xiaowu Li
- Department of Hepatobiliary Surgery, Guangdong Provincial Key Laboratory of Regional Immunity and Diseases & Carson International Cancer Center, Shenzhen University General Hospital & Shenzhen University Clinical Medical Academy Center, Shenzhen University, Shenzhen, China
| | - Jolanda Spadavecchia
- CNRS, UMR 7244, NBD-CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Paris 13, Sorbonne Paris Nord, Bobigny, France.,Department of Hepatobiliary Surgery, Guangdong Provincial Key Laboratory of Regional Immunity and Diseases & Carson International Cancer Center, Shenzhen University General Hospital & Shenzhen University Clinical Medical Academy Center, Shenzhen University, Shenzhen, China
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Zhou G, Pan Q, Hu Z, Qiu J, Yu Z. Heterologous Expression and Characterization of Flavinadenine Dinucleotide Synthetase from Candida famata for Flavin Adenine Dinucleotide Production. Protein Pept Lett 2021; 28:229-239. [PMID: 32640951 DOI: 10.2174/0929866527666200708151327] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/02/2020] [Accepted: 06/05/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Flavin adenine dinucleotide (FAD) is a redox-active coenzyme that regulates several important enzymatic reactions during metabolism. FAD is used in the medicinal and food industries and FAD supplements have been used to treat some inheritable diseases. FAD can be biosynthesized from flavin mononucleotide (FMN) and adenosine triphosphate (ATP), catalyzed by FAD synthetase (FADS). OBJECTIVE The aim of this study was to heterologously express the gene encoding FADS from the flavinogenic yeast Candida famata (FADSCf) for biosynthesis of FAD. METHODS The sequence encoding FADSCf was retrieved and heterologously expressed in Escherichia coli. The structure and enzymatic properties of recombinant FADSCf were characterized. RESULTS FADSCf (279 amino acids) was successfully expressed in E. coli BL21 (DE3), with a theoretical molecular weight of 32299.79 Da and an isoelectric point of 6.09. Secondary structural analysis showed that the number of α-helices was 2-fold higher than the number of β-sheets, indicating that the protein was highly hydrophilic. Under fixed ATP concentration, FADSCf had a Km of 0.04737±0.03158 mM and a Vmax of 3.271±0.79 μM/min/mg. Under fixed FMN concentration, FADSCf had a Km of 0.1214±0.07464 mM and a Vmax of 2.6695±0.3715 μM/min/mg. Enzymatic reactions in vitro showed that expressed FADSCf could form 80 mM of FAD per mg of enzyme after 21 hours under the following conditions: 0.5 mM FMN, 5 mM ATP and 10 mM Mg2+. CONCLUSION Under optimized conditions (0.5 mM FMN, 5 mM ATP and 10 mM Mg2+), the production of FAD reached 80 mM per mg of FADSCf after a 21-hour reaction. Our results indicate that purified recombinant FADSCf can be used for the biosynthesis of FAD.
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Affiliation(s)
- Guoqiang Zhou
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou-310014, China
| | - Qiaoqiao Pan
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou-310014, China
| | - Zeyu Hu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou-310014, China
| | - Juanping Qiu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou-310014, China
| | - Zhiliang Yu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou-310014, China
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11
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Du W, Ruan C, Li J, Li H, Ding J, Zhao S, Jiang X. Quantitative proteomic analysis of Xanthoceras sorbifolium Bunge seedlings in response to drought and heat stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 160:8-17. [PMID: 33445043 DOI: 10.1016/j.plaphy.2021.01.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
Yellowhorn (Xanthoceras sorbifolium Bunge) is a woody oil species that is widely distributed in northwestern China. To investigate the molecular mechanisms underlying the drought and heat tolerance response of yellowhorn seedlings, changes in protein abundance were analyzed via comparative proteomics. Drought and heat treatment of seedlings was applied in growth chamber, and the leaves were harvested after 7 days of treatment. The total protein was extracted, and comparative proteomic analysis was performed via isobaric tag for relative and absolute quantitation (iTRAQ). The abundance of most of the proteins associated with oxidative phosphorylation, NADH dehydrogenase and superoxide dismutase (SOD) was reduced. The differential proteins associated with photosynthesis enzymes indicated that stress had different effects on photosystem I (PSI) and photosystem II (PSII). After comprehensively analyzing the results, we speculated that drought and heat stress could hinder the synthesis of riboflavin, reducing NADH dehydrogenase content, which might further have an impact on energy utilization. Yellowhorn seedlings relied on Fe-Mn SOD enzymes rather than Cu/Zn SOD enzymes to remove reactive oxygen species (ROS). In addition, heat-shock proteins (HSPs) had significant increase and played a key role in stress response, which could be divided into two categories according to their transcription and translation efficiency. Over all, the results can provide a basis for understanding the molecular mechanism underlying resistance to drought and heat stress in yellowhorn and for subsequent research of posttranslational modification-related omics of key proteins.
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Affiliation(s)
- Wei Du
- Institute of Plant Resources, Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Nationalities University, Dalian, 116600, China
| | - Chengjiang Ruan
- Institute of Plant Resources, Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Nationalities University, Dalian, 116600, China.
| | - Jingbin Li
- Institute of Plant Resources, Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Nationalities University, Dalian, 116600, China
| | - He Li
- Institute of Plant Resources, Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Nationalities University, Dalian, 116600, China
| | - Jian Ding
- Institute of Plant Resources, Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Nationalities University, Dalian, 116600, China
| | - Siyang Zhao
- Institute of Plant Resources, Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Nationalities University, Dalian, 116600, China
| | - Xin Jiang
- Institute of Plant Resources, Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Nationalities University, Dalian, 116600, China
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12
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Jiang L, Strobbe S, Van Der Straeten D, Zhang C. Regulation of plant vitamin metabolism: backbone of biofortification for the alleviation of hidden hunger. MOLECULAR PLANT 2021; 14:40-60. [PMID: 33545049 DOI: 10.1016/j.molp.2020.11.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/22/2020] [Accepted: 11/25/2020] [Indexed: 05/04/2023]
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Leone P, Tolomeo M, Barile M. Continuous and Discontinuous Approaches to Study FAD Synthesis and Degradation Catalyzed by Purified Recombinant FAD Synthase or Cellular Fractions. Methods Mol Biol 2021; 2280:87-116. [PMID: 33751431 DOI: 10.1007/978-1-0716-1286-6_7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Riboflavin, or vitamin B2, is the precursor of flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), essential redox (and sometimes non-redox) cofactors of a large number of flavoenzymes involved in energetic metabolism, protein folding, apoptosis, chromatin remodeling, and a number of other cell regulatory processes.The cellular and subcellular steady-state concentrations of flavin cofactors, which are available for flavoprotein biogenesis and assembly, depend on carrier-mediated transport processes and on coordinated synthesizing/destroying enzymatic activities, catalyzed by enzymes whose catalytic and structural properties are still matter of investigation.Alteration of flavin homeostasis has been recently correlated to human pathological conditions, such as neuromuscular disorders and cancer, and therefore we propose here protocols useful to detect metabolic processes involved in FAD forming and destroying.Our protocols exploit the chemical-structural differences between riboflavin, FMN , and FAD , which are responsible for differences in the spectroscopic properties (mainly fluorescence) of the two cofactors (FMN and FAD); therefore, in our opinion, when applicable measurements of fluorescence changes in continuo represent the elective techniques to follow FAD synthesis and degradation. Thus, after procedures able to calibrate flavin concentrations (Subheading 3.1), we describe simple continuous and rapid procedures, based on the peculiar optical properties of free flavins, useful to determine the rate of cofactor metabolism catalyzed by either recombinant enzymes or natural enzymes present in cellular lysates/subfractions (Subheading 3.2).Fluorescence properties of free flavins can also be useful in analytical determinations of the three molecular flavin forms, based on HPLC separation, with a quite high sensitivity. Assaying at different incubation times the molecular composition of the reaction mixture is a discontinuous experimental approach to measure the rate of FAD synthesis/degradation catalyzed by cell lysates or recombinant FAD synthase (Subheading 3.3). Continuous and discontinuous approaches can, when necessary, be performed in parallel.
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Affiliation(s)
- Piero Leone
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari "A. Moro", Bari, Italy
| | - Maria Tolomeo
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari "A. Moro", Bari, Italy
| | - Maria Barile
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari "A. Moro", Bari, Italy.
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Hu L, Wang N, Cardona E, Walsh AJ. Fluorescence intensity and lifetime redox ratios detect metabolic perturbations in T cells. BIOMEDICAL OPTICS EXPRESS 2020; 11:5674-5688. [PMID: 33149978 PMCID: PMC7587263 DOI: 10.1364/boe.401935] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 08/21/2020] [Accepted: 09/08/2020] [Indexed: 05/17/2023]
Abstract
The auto-fluorescent coenzymes reduced nicotinamide dinucleotide (NADH) and oxidized flavin adenine dinucleotide (FAD) allow label-free detection of cellular metabolism. The optical redox ratio, which is traditionally computed as the ratio of NADH and FAD intensities, allows quantification of cell redox state. In addition to multiple formulations of the optical redox ratio from NADH and FAD intensity measurements, a fluorescence lifetime redox ratio (FLIRR) based on the fractions of protein-bound NADH and FAD was developed to overcome the limitations of experimental factors that influence fluorescence intensity measurements. In this paper, we compare fluorescence-intensity computations of the optical redox ratio with the fluorescence lifetime redox ratio for quiescent and activated T cells. Fluorescence lifetime images of NAD(P)H and FAD of T cells were acquired with a two-photon fluorescence lifetime microscope. Metabolic perturbation experiments, including inhibition of glycolysis, oxidative phosphorylation, glutaminolysis, and fatty acid synthesis revealed differences between the intensity and lifetime redox ratios. Statistical analysis reveals that the FLIRR has a lower standard deviation and skewness (two-tail T-test, P value = 0.05) than the intensity redox ratio. Correlation analysis revealed a weak relationship between FLIRR and intensity redox ratio for individual cells, with a stronger correlation identified for activated T cells (Linear regression, R-value = 0.450) than quiescent T cells (R-value = 0.172). Altogether, the results demonstrate that while both the fluorescence lifetime and intensity redox ratios resolve metabolic perturbations in T cells, the endpoints are influenced by different metabolic processes.
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Schall P, Marutschke L, Grimm B. The Flavoproteome of the Model Plant Arabidopsis thaliana. Int J Mol Sci 2020; 21:ijms21155371. [PMID: 32731628 PMCID: PMC7432721 DOI: 10.3390/ijms21155371] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/22/2020] [Accepted: 07/25/2020] [Indexed: 12/17/2022] Open
Abstract
Flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) are essential cofactors for enzymes, which catalyze a broad spectrum of vital reactions. This paper intends to compile all potential FAD/FMN-binding proteins encoded by the genome of Arabidopsis thaliana. Several computational approaches were applied to group the entire flavoproteome according to (i) different catalytic reactions in enzyme classes, (ii) the localization in subcellular compartments, (iii) different protein families and subclasses, and (iv) their classification to structural properties. Subsequently, the physiological significance of several of the larger flavoprotein families was highlighted. It is conclusive that plants, such as Arabidopsis thaliana, use many flavoenzymes for plant-specific and pivotal metabolic activities during development and for signal transduction pathways in response to biotic and abiotic stress. Thereby, often two up to several homologous genes are found encoding proteins with high protein similarity. It is proposed that these gene families for flavoproteins reflect presumably their need for differential transcriptional control or the expression of similar proteins with modified flavin-binding properties or catalytic activities.
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Tolomeo M, Nisco A, Leone P, Barile M. Development of Novel Experimental Models to Study Flavoproteome Alterations in Human Neuromuscular Diseases: The Effect of Rf Therapy. Int J Mol Sci 2020; 21:ijms21155310. [PMID: 32722651 PMCID: PMC7432027 DOI: 10.3390/ijms21155310] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 07/20/2020] [Accepted: 07/21/2020] [Indexed: 02/07/2023] Open
Abstract
Inborn errors of Riboflavin (Rf) transport and metabolism have been recently related to severe human neuromuscular disorders, as resulting in profound alteration of human flavoproteome and, therefore, of cellular bioenergetics. This explains why the interest in studying the “flavin world”, a topic which has not been intensively investigated before, has increased much over the last few years. This also prompts basic questions concerning how Rf transporters and FAD (flavin adenine dinucleotide) -forming enzymes work in humans, and how they can create a coordinated network ensuring the maintenance of intracellular flavoproteome. The concept of a coordinated cellular “flavin network”, introduced long ago studying humans suffering for Multiple Acyl-CoA Dehydrogenase Deficiency (MADD), has been, later on, addressed in model organisms and more recently in cell models. In the frame of the underlying relevance of a correct supply of Rf in humans and of a better understanding of the molecular rationale of Rf therapy in patients, this review wants to deal with theories and existing experimental models in the aim to potentiate possible therapeutic interventions in Rf-related neuromuscular diseases.
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17
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Meyer EH, Welchen E, Carrie C. Assembly of the Complexes of the Oxidative Phosphorylation System in Land Plant Mitochondria. ANNUAL REVIEW OF PLANT BIOLOGY 2019; 70:23-50. [PMID: 30822116 DOI: 10.1146/annurev-arplant-050718-100412] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Plant mitochondria play a major role during respiration by producing the ATP required for metabolism and growth. ATP is produced during oxidative phosphorylation (OXPHOS), a metabolic pathway coupling electron transfer with ADP phosphorylation via the formation and release of a proton gradient across the inner mitochondrial membrane. The OXPHOS system is composed of large, multiprotein complexes coordinating metal-containing cofactors for the transfer of electrons. In this review, we summarize the current state of knowledge about assembly of the OXPHOS complexes in land plants. We present the different steps involved in the formation of functional complexes and the regulatory mechanisms controlling the assembly pathways. Because several assembly steps have been found to be ancestral in plants-compared with those described in fungal and animal models-we discuss the evolutionary dynamics that lead to the conservation of ancestral pathways in land plant mitochondria.
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Affiliation(s)
- Etienne H Meyer
- Organelle Biology and Biotechnology Research Group, Max Planck Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
- Current affiliation: Institute of Plant Physiology, Martin-Luther-University Halle-Wittenberg, 06120 Halle, Germany;
| | - Elina Welchen
- Cátedra de Biología Celular y Molecular, Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, 3000 Santa Fe, Argentina
| | - Chris Carrie
- Plant Sciences Research Group, Department Biologie I, Ludwig-Maximilians-Universität, 82152 Planegg-Martinsried, Germany
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Cimini S, Gualtieri C, Macovei A, Balestrazzi A, De Gara L, Locato V. Redox Balance-DDR-miRNA Triangle: Relevance in Genome Stability and Stress Responses in Plants. FRONTIERS IN PLANT SCIENCE 2019; 10:989. [PMID: 31428113 PMCID: PMC6688120 DOI: 10.3389/fpls.2019.00989] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 07/15/2019] [Indexed: 05/05/2023]
Abstract
Plants are continuously faced with complex environmental conditions which can affect the oxidative metabolism and photosynthetic efficiency, thus leading to the over-production of reactive oxygen species (ROS). Over a certain threshold, ROS can damage DNA. DNA damage, unless repaired, can affect genome stability, thus interfering with cell survival and severely reducing crop productivity. A complex network of pathways involved in DNA damage response (DDR) needs to be activated in order to maintain genome integrity. The expression of specific genes belonging to these pathways can be used as indicators of oxidative DNA damage and effective DNA repair in plants subjected to stress conditions. Managing ROS levels by modulating their production and scavenging systems shifts the role of these compounds from toxic molecules to key messengers involved in plant tolerance acquisition. Oxidative and anti-oxidative signals normally move among the different cell compartments, including the nucleus, cytosol, and organelles. Nuclei are dynamically equipped with different redox systems, such as glutathione (GSH), thiol reductases, and redox regulated transcription factors (TFs). The nuclear redox network participates in the regulation of the DNA metabolism, in terms of transcriptional events, replication, and repair mechanisms. This mainly occurs through redox-dependent regulatory mechanisms comprising redox buffering and post-translational modifications, such as the thiol-disulphide switch, glutathionylation, and S-nitrosylation. The regulatory role of microRNAs (miRNAs) is also emerging for the maintenance of genome stability and the modulation of antioxidative machinery under adverse environmental conditions. In fact, redox systems and DDR pathways can be controlled at a post-transcriptional level by miRNAs. This review reports on the interconnections between the DDR pathways and redox balancing systems. It presents a new dynamic picture by taking into account the shared regulatory mechanism mediated by miRNAs in plant defense responses to stress.
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Affiliation(s)
- Sara Cimini
- Unit of Food Science and Human Nutrition, Campus Bio-Medico University of Rome, Rome, Italy
| | - Carla Gualtieri
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - Anca Macovei
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - Alma Balestrazzi
- Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | - Laura De Gara
- Unit of Food Science and Human Nutrition, Campus Bio-Medico University of Rome, Rome, Italy
| | - Vittoria Locato
- Unit of Food Science and Human Nutrition, Campus Bio-Medico University of Rome, Rome, Italy
- *Correspondence: Vittoria Locato,
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19
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Lynch JH, Sa N, Saeheng S, Raffaelli N, Roje S. Characterization of a non-nudix pyrophosphatase points to interplay between flavin and NAD(H) homeostasis in Saccharomyces cerevisiae. PLoS One 2018; 13:e0198787. [PMID: 29902190 PMCID: PMC6002036 DOI: 10.1371/journal.pone.0198787] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 05/28/2018] [Indexed: 12/11/2022] Open
Abstract
The flavin cofactors FMN and FAD are required for a wide variety of biological processes, however, little is known about their metabolism. Here, we report the cloning and biochemical characterization of the Saccharomyces cerevisiae pyrophosphatase Fpy1p. Genetic and functional studies suggest that Fpy1p may play a key role in flavin metabolism and is the first-reported non-Nudix superfamily enzyme to display FAD pyrophosphatase activity. Characterization of mutant yeast strains found that deletion of fpy1 counteracts the adverse effects that are caused by deletion of flx1, a known mitochondrial FAD transporter. We show that Fpy1p is capable of hydrolyzing FAD, NAD(H), and ADP-ribose. The enzymatic activity of Fpy1p is dependent upon the presence of K+ and divalent metal cations, with similar kinetic parameters to those that have been reported for Nudix FAD pyrophosphatases. In addition, we report that the deletion of fpy1 intensifies the FMN-dependence of null mutants of the riboflavin kinase Fmn1p, demonstrate that fpy1 mutation abolishes the decreased fitness resulting from the deletion of the flx1 ORF, and offer a possible mechanism for the genetic interplay between fpy1, flx1 and fmn1.
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Affiliation(s)
- Joseph H. Lynch
- Institute of Biological Chemistry, Washington State University, Pullman, WA, United States of America
| | - Na Sa
- Institute of Biological Chemistry, Washington State University, Pullman, WA, United States of America
| | - Sompop Saeheng
- Institute of Biological Chemistry, Washington State University, Pullman, WA, United States of America
| | - Nadia Raffaelli
- Dipartimento di Scienze Agrarie, Alimentari e Ambientali, Università Politecnica delle Marche, Ancona, Italy
| | - Sanja Roje
- Institute of Biological Chemistry, Washington State University, Pullman, WA, United States of America
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20
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Biochemistry and Physiology of Vitamins in Euglena. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 979:65-90. [DOI: 10.1007/978-3-319-54910-1_5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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21
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Olsen RKJ, Koňaříková E, Giancaspero TA, Mosegaard S, Boczonadi V, Mataković L, Veauville-Merllié A, Terrile C, Schwarzmayr T, Haack TB, Auranen M, Leone P, Galluccio M, Imbard A, Gutierrez-Rios P, Palmfeldt J, Graf E, Vianey-Saban C, Oppenheim M, Schiff M, Pichard S, Rigal O, Pyle A, Chinnery PF, Konstantopoulou V, Möslinger D, Feichtinger RG, Talim B, Topaloglu H, Coskun T, Gucer S, Botta A, Pegoraro E, Malena A, Vergani L, Mazzà D, Zollino M, Ghezzi D, Acquaviva C, Tyni T, Boneh A, Meitinger T, Strom TM, Gregersen N, Mayr JA, Horvath R, Barile M, Prokisch H. Riboflavin-Responsive and -Non-responsive Mutations in FAD Synthase Cause Multiple Acyl-CoA Dehydrogenase and Combined Respiratory-Chain Deficiency. Am J Hum Genet 2016; 98:1130-1145. [PMID: 27259049 PMCID: PMC4908180 DOI: 10.1016/j.ajhg.2016.04.006] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 04/13/2016] [Indexed: 12/27/2022] Open
Abstract
Multiple acyl-CoA dehydrogenase deficiencies (MADDs) are a heterogeneous group of metabolic disorders with combined respiratory-chain deficiency and a neuromuscular phenotype. Despite recent advances in understanding the genetic basis of MADD, a number of cases remain unexplained. Here, we report clinically relevant variants in FLAD1, which encodes FAD synthase (FADS), as the cause of MADD and respiratory-chain dysfunction in nine individuals recruited from metabolic centers in six countries. In most individuals, we identified biallelic frameshift variants in the molybdopterin binding (MPTb) domain, located upstream of the FADS domain. Inasmuch as FADS is essential for cellular supply of FAD cofactors, the finding of biallelic frameshift variants was unexpected. Using RNA sequencing analysis combined with protein mass spectrometry, we discovered FLAD1 isoforms, which only encode the FADS domain. The existence of these isoforms might explain why affected individuals with biallelic FLAD1 frameshift variants still harbor substantial FADS activity. Another group of individuals with a milder phenotype responsive to riboflavin were shown to have single amino acid changes in the FADS domain. When produced in E. coli, these mutant FADS proteins resulted in impaired but detectable FADS activity; for one of the variant proteins, the addition of FAD significantly improved protein stability, arguing for a chaperone-like action similar to what has been reported in other riboflavin-responsive inborn errors of metabolism. In conclusion, our studies identify FLAD1 variants as a cause of potentially treatable inborn errors of metabolism manifesting with MADD and shed light on the mechanisms by which FADS ensures cellular FAD homeostasis.
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MESH Headings
- Adult
- Blotting, Western
- Case-Control Studies
- Cells, Cultured
- Electron Transport
- Female
- Fibroblasts/drug effects
- Fibroblasts/metabolism
- Fibroblasts/pathology
- Flavin-Adenine Dinucleotide/metabolism
- Frameshift Mutation/genetics
- Gene Expression Profiling
- Humans
- Infant
- Infant, Newborn
- Liver/drug effects
- Liver/metabolism
- Liver/pathology
- Male
- Mitochondrial Diseases/drug therapy
- Mitochondrial Diseases/genetics
- Mitochondrial Diseases/pathology
- Multiple Acyl Coenzyme A Dehydrogenase Deficiency/drug therapy
- Multiple Acyl Coenzyme A Dehydrogenase Deficiency/genetics
- Multiple Acyl Coenzyme A Dehydrogenase Deficiency/pathology
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Mutagenesis, Site-Directed
- Nucleotidyltransferases/genetics
- Protein Binding
- RNA, Messenger/genetics
- Real-Time Polymerase Chain Reaction
- Reverse Transcriptase Polymerase Chain Reaction
- Riboflavin/pharmacology
- Skin/drug effects
- Skin/metabolism
- Skin/pathology
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
- Vitamin B Complex/pharmacology
- Young Adult
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Affiliation(s)
- Rikke K J Olsen
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and University Hospital, 8200 Aarhus N, Denmark.
| | - Eliška Koňaříková
- Institute of Human Genetics, Technische Universität München, 81675 Munich, Germany; Institute of Human Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Teresa A Giancaspero
- Department of Biosciences, Biotechnology, and Biopharmaceutics, University of Bari Aldo Moro, 70125 Bari, Italy
| | - Signe Mosegaard
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and University Hospital, 8200 Aarhus N, Denmark
| | - Veronika Boczonadi
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Lavinija Mataković
- Department of Paediatrics, Paracelsus Medical University, SALK Salzburg, 5020 Salzburg, Austria
| | - Alice Veauville-Merllié
- Service Maladies Héréditaires du Métabolisme et Dépistage Néonatal, Centre de Biologie et Pathologie Est, Centre Hospitalier Universitaire Lyon, 69500 Bron, France
| | - Caterina Terrile
- Institute of Human Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Thomas Schwarzmayr
- Institute of Human Genetics, Technische Universität München, 81675 Munich, Germany; Institute of Human Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Tobias B Haack
- Institute of Human Genetics, Technische Universität München, 81675 Munich, Germany; Institute of Human Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Mari Auranen
- Clinical Neurosciences, Neurology, University of Helsinki and Helsinki University Hospital, 340 Helsinki, Finland
| | - Piero Leone
- Department of Biosciences, Biotechnology, and Biopharmaceutics, University of Bari Aldo Moro, 70125 Bari, Italy
| | - Michele Galluccio
- Department DiBEST (Biology, Ecology, and Earth Sciences), University of Calabria, 87036 Arcavacata di Rende, Italy
| | - Apolline Imbard
- Biochemistry Hormonology Laboratory, Robert-Debré Hospital, 75019 Paris, France; Pharmacy Faculty, Paris Sud University, 92019 Chatenay-Malabry, France
| | - Purificacion Gutierrez-Rios
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK; Centro Andaluz de Biología del Desarrollo, Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Johan Palmfeldt
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and University Hospital, 8200 Aarhus N, Denmark
| | - Elisabeth Graf
- Institute of Human Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Christine Vianey-Saban
- Service Maladies Héréditaires du Métabolisme et Dépistage Néonatal, Centre de Biologie et Pathologie Est, Centre Hospitalier Universitaire Lyon, 69500 Bron, France
| | - Marcus Oppenheim
- Neurometabolic Unit, National Hospital for Neurology and Neurosurgery, London WCIN 3BG, UK
| | - Manuel Schiff
- INSERM UMR 1141, Hôpital Robert Debré, 75019 Paris, France; Reference Center for Inherited Metabolic Diseases, Robert-Debré Hospital, Assistance Publique - Hôpitaux de Paris, 75019 Paris, France; Faculté de Médecine Denis Diderot, Université Paris Diderot (Paris 7), 75013 Paris, France
| | - Samia Pichard
- Reference Center for Inherited Metabolic Diseases, Robert-Debré Hospital, Assistance Publique - Hôpitaux de Paris, 75019 Paris, France
| | - Odile Rigal
- Biochemistry Hormonology Laboratory, Robert-Debré Hospital, 75019 Paris, France
| | - Angela Pyle
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Patrick F Chinnery
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK; Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Cambridge CB2 0QQ, UK
| | | | - Dorothea Möslinger
- Department of Pediatrics, Medical University of Vienna, 1090 Vienna, Austria
| | - René G Feichtinger
- Department of Paediatrics, Paracelsus Medical University, SALK Salzburg, 5020 Salzburg, Austria
| | - Beril Talim
- Pathology Unit, Department of Pediatrics, Hacettepe University Children's Hospital, 06100 Ankara, Turkey
| | - Haluk Topaloglu
- Neurology Unit, Department of Pediatrics, Hacettepe University Children's Hospital, 06100 Ankara, Turkey
| | - Turgay Coskun
- Metabolism Unit, Department of Pediatrics, Hacettepe University Children's Hospital, 06100 Ankara, Turkey
| | - Safak Gucer
- Pathology Unit, Department of Pediatrics, Hacettepe University Children's Hospital, 06100 Ankara, Turkey
| | - Annalisa Botta
- Medical Genetics Section, Department of Biomedicine and Prevention, Tor Vergata University of Rome, 00133 Rome, Italy
| | - Elena Pegoraro
- Neuromuscular Center, Department of Neurosciences, University of Padova, 35129 Padova, Italy
| | - Adriana Malena
- Neuromuscular Center, Department of Neurosciences, University of Padova, 35129 Padova, Italy
| | - Lodovica Vergani
- Neuromuscular Center, Department of Neurosciences, University of Padova, 35129 Padova, Italy
| | - Daniela Mazzà
- Italy Institute of Medical Genetics, Catholic University of Roma, 00168 Rome, Italy
| | - Marcella Zollino
- Italy Institute of Medical Genetics, Catholic University of Roma, 00168 Rome, Italy
| | - Daniele Ghezzi
- Molecular Neurogenetics Unit, Foundation IRCCS Neurological Institute C. Besta, 20126 Milan, Italy
| | - Cecile Acquaviva
- Service Maladies Héréditaires du Métabolisme et Dépistage Néonatal, Centre de Biologie et Pathologie Est, Centre Hospitalier Universitaire Lyon, 69500 Bron, France
| | - Tiina Tyni
- Department of Pediatric Neurology, Hospital for Children and Adolescence, Helsinki University Central Hospital, 280 Helsinki, Finland
| | - Avihu Boneh
- Murdoch Childrens Research Institute and University of Melbourne, Melbourne, VIC 3010, Australia
| | - Thomas Meitinger
- Institute of Human Genetics, Technische Universität München, 81675 Munich, Germany; Institute of Human Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Tim M Strom
- Institute of Human Genetics, Technische Universität München, 81675 Munich, Germany; Institute of Human Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
| | - Niels Gregersen
- Research Unit for Molecular Medicine, Department of Clinical Medicine, Aarhus University and University Hospital, 8200 Aarhus N, Denmark
| | - Johannes A Mayr
- Department of Paediatrics, Paracelsus Medical University, SALK Salzburg, 5020 Salzburg, Austria
| | - Rita Horvath
- Wellcome Trust Centre for Mitochondrial Research, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Maria Barile
- Department of Biosciences, Biotechnology, and Biopharmaceutics, University of Bari Aldo Moro, 70125 Bari, Italy.
| | - Holger Prokisch
- Institute of Human Genetics, Technische Universität München, 81675 Munich, Germany; Institute of Human Genetics, Helmholtz Zentrum München, 85764 Neuherberg, Germany
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22
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Herguedas B, Lans I, Sebastián M, Hermoso JA, Martínez-Júlvez M, Medina M. Structural insights into the synthesis of FMN in prokaryotic organisms. ACTA ACUST UNITED AC 2015; 71:2526-42. [PMID: 26627660 DOI: 10.1107/s1399004715019641] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 10/16/2015] [Indexed: 11/10/2022]
Abstract
Riboflavin kinases (RFKs) catalyse the phosphorylation of riboflavin to produce FMN. In most bacteria this activity is catalysed by the C-terminal module of a bifunctional enzyme, FAD synthetase (FADS), which also catalyses the transformation of FMN into FAD through its N-terminal FMN adenylyltransferase (FMNAT) module. The RFK module of FADS is a homologue of eukaryotic monofunctional RFKs, while the FMNAT module lacks homologyto eukaryotic enzymes involved in FAD production. Previously, the crystal structure of Corynebacterium ammoniagenes FADS (CaFADS) was determined in its apo form. This structure predicted a dimer-of-trimers organization with the catalytic sites of two modules of neighbouring protomers approaching each other, leading to a hypothesis about the possibility of FMN channelling in the oligomeric protein. Here, two crystal structures of the individually expressed RFK module of CaFADS in complex with the products of the reaction, FMN and ADP, are presented. Structures are complemented with computational simulations, binding studies and kinetic characterization. Binding of ligands triggers dramatic structural changes in the RFK module, which affect large portions of the protein. Substrate inhibition and molecular-dynamics simulations allowed the conformational changes that take place along the RFK catalytic cycle to be established. The influence of these conformational changes in the FMNAT module is also discussed in the context of the full-length CaFADS protomer and the quaternary organization.
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Affiliation(s)
- Beatriz Herguedas
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, and Instituto de Biocomputación y Física de Sistemas Complejos (Joint Unit BIFI-IQFR), Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Isaias Lans
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, and Instituto de Biocomputación y Física de Sistemas Complejos (Joint Unit BIFI-IQFR), Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - María Sebastián
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, and Instituto de Biocomputación y Física de Sistemas Complejos (Joint Unit BIFI-IQFR), Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Juan A Hermoso
- GCMBE - Instituto Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain
| | - Marta Martínez-Júlvez
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, and Instituto de Biocomputación y Física de Sistemas Complejos (Joint Unit BIFI-IQFR), Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Milagros Medina
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, and Instituto de Biocomputación y Física de Sistemas Complejos (Joint Unit BIFI-IQFR), Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
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Giancaspero TA, Colella M, Brizio C, Difonzo G, Fiorino GM, Leone P, Brandsch R, Bonomi F, Iametti S, Barile M. Remaining challenges in cellular flavin cofactor homeostasis and flavoprotein biogenesis. Front Chem 2015; 3:30. [PMID: 25954742 PMCID: PMC4406087 DOI: 10.3389/fchem.2015.00030] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 04/05/2015] [Indexed: 12/27/2022] Open
Abstract
The primary role of the water-soluble vitamin B2 (riboflavin) in cell biology is connected with its conversion into FMN and FAD, the cofactors of a large number of dehydrogenases, oxidases and reductases involved in a broad spectrum of biological activities, among which energetic metabolism and chromatin remodeling. Subcellular localisation of FAD synthase (EC 2.7.7.2, FADS), the second enzyme in the FAD forming pathway, is addressed here in HepG2 cells by confocal microscopy, in the frame of its relationships with kinetics of FAD synthesis and delivery to client apo-flavoproteins. FAD synthesis catalyzed by recombinant isoform 2 of FADS occurs via an ordered bi-bi mechanism in which ATP binds prior to FMN, and pyrophosphate is released before FAD. Spectrophotometric continuous assays of the reconstitution rate of apo-D-aminoacid oxidase with its cofactor, allowed us to propose that besides its FAD synthesizing activity, hFADS is able to operate as a FAD “chaperone.” The physical interaction between FAD forming enzyme and its clients was further confirmed by dot blot and immunoprecipitation experiments carried out testing as a client either a nuclear lysine-specific demethylase 1 (LSD1) or a mitochondrial dimethylglycine dehydrogenase (Me2GlyDH, EC 1.5.8.4). Both enzymes carry out similar reactions of oxidative demethylation, in which tetrahydrofolate is converted into 5,10-methylene-tetrahydrofolate. A direct transfer of the cofactor from hFADS2 to apo-dimethyl glycine dehydrogenase was also demonstrated. Thus, FAD synthesis and delivery to these enzymes are crucial processes for bioenergetics and nutri-epigenetics of liver cells.
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Affiliation(s)
- Teresa A Giancaspero
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari Aldo Moro Bari, Italy
| | - Matilde Colella
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari Aldo Moro Bari, Italy
| | - Carmen Brizio
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari Aldo Moro Bari, Italy
| | - Graziana Difonzo
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari Aldo Moro Bari, Italy
| | - Giuseppina M Fiorino
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari Aldo Moro Bari, Italy
| | - Piero Leone
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari Aldo Moro Bari, Italy
| | - Roderich Brandsch
- Institut für Biochemie und Molekularbiologie, Universität Freiburg Freiburg, Germany
| | - Francesco Bonomi
- Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente, Università degli Studi di Milano Milano, Italy
| | - Stefania Iametti
- Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente, Università degli Studi di Milano Milano, Italy
| | - Maria Barile
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari Aldo Moro Bari, Italy ; Dipartimento di Scienze della Vita, Istituto di Biomembrane e Bioenergetica, CNR Bari, Italy
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Li L, Hu L, Han LP, Ji H, Zhu Y, Wang X, Ge J, Xu M, Shen D, Dong H. Expression of turtle riboflavin-binding protein represses mitochondrial electron transport gene expression and promotes flowering in Arabidopsis. BMC PLANT BIOLOGY 2014; 14:381. [PMID: 25547226 PMCID: PMC4310184 DOI: 10.1186/s12870-014-0381-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 12/11/2014] [Indexed: 05/12/2023]
Abstract
BACKGROUND Recently we showed that de novo expression of a turtle riboflavin-binding protein (RfBP) in transgenic Arabidopsis increased H2O2 concentrations inside leaf cells, enhanced the expression of floral regulatory gene FD and floral meristem identity gene AP1 at the shoot apex, and induced early flowering. Here we report that RfBP-induced H2O2 presumably results from electron leakage at the mitochondrial electron transport chain (METC) and this source of H2O2 contributes to the early flowering phenotype. RESULTS While enhanced expression of FD and AP1 at the shoot apex was correlated with early flowering, the foliar expression of 13 of 19 METC genes was repressed in RfBP-expressing (RfBP+) plants. Inside RfBP+ leaf cells, cytosolic H2O2 concentrations were increased possibly through electron leakage because similar responses were also induced by a known inducer of electron leakage from METC. Early flowering no longer occurred when the repression on METC genes was eliminated by RfBP gene silencing, which restored RfBP+ to wild type in levels of FD and AP1 expression, H2O2, and flavins. Flowering was delayed by the external riboflavin application, which brought gene expression and flavins back to the steady-state levels but only caused 55% reduction of H2O2 concentrations in RfBP+ plants. RfBP-repressed METC gene expression remedied the cytosolic H2O2 diminution by genetic disruption of transcription factor NFXLl and compensated for compromises in FD and AP1 expression and flowering time. By contrast, RfBP resembled a peroxisomal catalase mutation, which augments the cytosolic H2O2, to enhance FD and AP1 expression and induce early flowering. CONCLUSIONS RfBP-repressed METC gene expression potentially causes electron leakage as one of cellular sources for the generation of H2O2 with the promoting effect on flowering. The repressive effect on METC gene expression is not the only way by which RfBP induces H2O2 and currently unappreciated factors may also function under RfBP+ background.
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Affiliation(s)
- Liang Li
- Department of Plant Pathology, Nanjing Agricultural University and State Ministry of Education Key Laboratory of Integrated Management of Crop Pathogens and Insect Pests, Nanjing, 210095 China
| | - Li Hu
- Department of Plant Pathology, Nanjing Agricultural University and State Ministry of Education Key Laboratory of Integrated Management of Crop Pathogens and Insect Pests, Nanjing, 210095 China
| | - Li-Ping Han
- Department of Plant Pathology, Nanjing Agricultural University and State Ministry of Education Key Laboratory of Integrated Management of Crop Pathogens and Insect Pests, Nanjing, 210095 China
| | - Hongtao Ji
- Department of Plant Pathology, Nanjing Agricultural University and State Ministry of Education Key Laboratory of Integrated Management of Crop Pathogens and Insect Pests, Nanjing, 210095 China
| | - Yueyue Zhu
- Department of Plant Pathology, Nanjing Agricultural University and State Ministry of Education Key Laboratory of Integrated Management of Crop Pathogens and Insect Pests, Nanjing, 210095 China
| | - Xiaobing Wang
- Department of Plant Pathology, Nanjing Agricultural University and State Ministry of Education Key Laboratory of Integrated Management of Crop Pathogens and Insect Pests, Nanjing, 210095 China
| | - Jun Ge
- Department of Plant Pathology, Nanjing Agricultural University and State Ministry of Education Key Laboratory of Integrated Management of Crop Pathogens and Insect Pests, Nanjing, 210095 China
| | - Manyu Xu
- Department of Plant Pathology, Nanjing Agricultural University and State Ministry of Education Key Laboratory of Integrated Management of Crop Pathogens and Insect Pests, Nanjing, 210095 China
| | - Dan Shen
- Department of Plant Pathology, Nanjing Agricultural University and State Ministry of Education Key Laboratory of Integrated Management of Crop Pathogens and Insect Pests, Nanjing, 210095 China
| | - Hansong Dong
- Department of Plant Pathology, Nanjing Agricultural University and State Ministry of Education Key Laboratory of Integrated Management of Crop Pathogens and Insect Pests, Nanjing, 210095 China
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Giancaspero TA, Dipalo E, Miccolis A, Boles E, Caselle M, Barile M. Alteration of ROS homeostasis and decreased lifespan in S. cerevisiae elicited by deletion of the mitochondrial translocator FLX1. BIOMED RESEARCH INTERNATIONAL 2014; 2014:101286. [PMID: 24895546 PMCID: PMC4033422 DOI: 10.1155/2014/101286] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 03/20/2014] [Accepted: 04/01/2014] [Indexed: 01/15/2023]
Abstract
This paper deals with the control exerted by the mitochondrial translocator FLX1, which catalyzes the movement of the redox cofactor FAD across the mitochondrial membrane, on the efficiency of ATP production, ROS homeostasis, and lifespan of S. cerevisiae. The deletion of the FLX1 gene resulted in respiration-deficient and small-colony phenotype accompanied by a significant ATP shortage and ROS unbalance in glycerol-grown cells. Moreover, the flx1Δ strain showed H2O2 hypersensitivity and decreased lifespan. The impaired biochemical phenotype found in the flx1Δ strain might be justified by an altered expression of the flavoprotein subunit of succinate dehydrogenase, a key enzyme in bioenergetics and cell regulation. A search for possible cis-acting consensus motifs in the regulatory region upstream SDH1-ORF revealed a dozen of upstream motifs that might respond to induced metabolic changes by altering the expression of Flx1p. Among these motifs, two are present in the regulatory region of genes encoding proteins involved in flavin homeostasis. This is the first evidence that the mitochondrial flavin cofactor status is involved in controlling the lifespan of yeasts, maybe by changing the cellular succinate level. This is not the only case in which the homeostasis of redox cofactors underlies complex phenotypical behaviours, as lifespan in yeasts.
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Affiliation(s)
| | - Emilia Dipalo
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari “A. Moro”, Via Orabona 4, 70126 Bari, Italy
| | - Angelica Miccolis
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari “A. Moro”, Via Orabona 4, 70126 Bari, Italy
| | - Eckhard Boles
- Institute of Molecular Biosciences, Goethe University Frankfurt, Max-von-Laue Straße 9, 60438 Frankfurt am Main, Germany
| | - Michele Caselle
- Dipartimento di Fisica, Via P. Giuria 1, 10125 Torino, Italy
| | - Maria Barile
- Istituto di Biomembrane e Bioenergetica, CNR, Via Amendola 165/A, 70126 Bari, Italy
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari “A. Moro”, Via Orabona 4, 70126 Bari, Italy
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Solti Á, Müller B, Czech V, Sárvári É, Fodor F. Functional characterization of the chloroplast ferric chelate oxidoreductase enzyme. THE NEW PHYTOLOGIST 2014; 202:920-928. [PMID: 24506824 DOI: 10.1111/nph.12715] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 01/08/2014] [Indexed: 05/24/2023]
Abstract
Iron (Fe) has an essential role in the biosynthesis of chlorophylls and redox cofactors, and thus chloroplast iron uptake is a process of special importance. The chloroplast ferric chelate oxidoreductase (cFRO) has a crucial role in this process but it is poorly characterized. To study the localization and mechanism of action of cFRO, sugar beet (Beta vulgaris cv Orbis) chloroplast envelope fractions were isolated by gradient ultracentrifugation, and their purity was tested by western blotting against different marker proteins. The ferric chelate reductase (FCR) activity of envelope fractions was studied in the presence of NAD(P)H (reductants) and FAD coenzymes. Reduction of Fe(III)-ethylenediaminetetraacetic acid was monitored spectrophotometrically by the Fe(II)-bathophenanthroline disulfonate complex formation. FCR activity, that is production of free Fe(II) for Fe uptake, showed biphasic saturation kinetics, and was clearly associated only to chloroplast inner envelope (cIE) vesicles. The reaction rate was > 2.5 times higher with NADPH than with NADH, which indicates the natural coenzyme preference of cFRO activity and its dependence on photosynthesis. FCR activity of cIE vesicles isolated from Fe-deficient plants also showed clear biphasic kinetics, where the KM of the low affinity component was elevated, and thus this component was down-regulated.
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Affiliation(s)
- Ádám Solti
- Department of Plant Physiology and Molecular Plant Biology, Institute of Biology, Eötvös Loránd University, Pázmány P. sétány 1/C, Budapest, 1117, Hungary
| | - Brigitta Müller
- Department of Plant Physiology and Molecular Plant Biology, Institute of Biology, Eötvös Loránd University, Pázmány P. sétány 1/C, Budapest, 1117, Hungary
| | - Viktória Czech
- Department of Plant Physiology and Molecular Plant Biology, Institute of Biology, Eötvös Loránd University, Pázmány P. sétány 1/C, Budapest, 1117, Hungary
| | - Éva Sárvári
- Department of Plant Physiology and Molecular Plant Biology, Institute of Biology, Eötvös Loránd University, Pázmány P. sétány 1/C, Budapest, 1117, Hungary
| | - Ferenc Fodor
- Department of Plant Physiology and Molecular Plant Biology, Institute of Biology, Eötvös Loránd University, Pázmány P. sétány 1/C, Budapest, 1117, Hungary
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27
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Serrano A, Frago S, Herguedas B, Martínez-Júlvez M, Velázquez-Campoy A, Medina M. Key residues at the riboflavin kinase catalytic site of the bifunctional riboflavin kinase/FMN adenylyltransferase from Corynebacterium ammoniagenes. Cell Biochem Biophys 2013; 65:57-68. [PMID: 22892871 DOI: 10.1007/s12013-012-9403-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Many known prokaryotic organisms depend on a single bifunctional enzyme, encoded by the RibC of RibF gene and named FAD synthetase (FADS), to convert Riboflavin (RF), first into FMN and then into FAD. The reaction occurs through the sequential action of two activities present on a single polypeptide chain where the N-terminus is responsible for the ATP:FMN adenylyltransferase (FMNAT) activity and the C-terminus for the ATP: riboflavin kinase (RFK) activity. Sequence and structural analysis suggest that T208, N210 and E268 at the C-terminus RFK module of Corynebacterium ammoniagenes FADS (CaFADS) might be key during RF phosphorylation. The effect of site-directed mutagenesis on the RFK activity, as well as on substrates and products binding, indicates that T208 and N210 provide the RFK active-site geometry for binding and catalysis, while E268 might be involved in the catalytic step as catalytic base. These data additionally suggest concerted conformational changes at the RFK module of CaFADS during its activity. Mutations at the RFK site also modulate the binding parameters at the FMNAT active site of CaFADS, altering the catalytic efficiency in the transformation of FMN into FAD. This observation supports the hypothesis that the hexameric assembly previously revealed by the crystal structure of CaFADS might play a functional role during catalysis.
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Affiliation(s)
- Ana Serrano
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Pedro Cerbuna, 12, 50009 Saragossa, Spain
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28
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Giancaspero TA, Locato V, Barile M. A regulatory role of NAD redox status on flavin cofactor homeostasis in S. cerevisiae mitochondria. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2013; 2013:612784. [PMID: 24078860 PMCID: PMC3774037 DOI: 10.1155/2013/612784] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 07/18/2013] [Indexed: 01/18/2023]
Abstract
Flavin adenine dinucleotide (FAD) and nicotinamide adenine dinucleotide (NAD) are two redox cofactors of pivotal importance for mitochondrial functionality and cellular redox balance. Despite their relevance, the mechanism by which intramitochondrial NAD(H) and FAD levels are maintained remains quite unclear in Saccharomyces cerevisiae. We investigated here the ability of isolated mitochondria to degrade externally added FAD and NAD (in both its reduced and oxidized forms). A set of kinetic experiments demonstrated that mitochondrial FAD and NAD(H) destroying enzymes are different from each other and from the already characterized NUDIX hydrolases. We studied here, in some detail, FAD pyrophosphatase (EC 3.6.1.18), which is inhibited by NAD(+) and NADH according to a noncompetitive inhibition, with Ki values that differ from each other by an order of magnitude. These findings, together with the ability of mitochondrial FAD pyrophosphatase to metabolize endogenous FAD, presumably deriving from mitochondrial holoflavoproteins destined to degradation, allow for proposing a novel possible role of mitochondrial NAD redox status in regulating FAD homeostasis and/or flavoprotein degradation in S. cerevisiae.
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Affiliation(s)
| | - Vittoria Locato
- Centro Integrato di Ricerca, Università Campus Bio-Medico di Roma, Via Alvaro del Portillo 21, 00128 Roma, Italy
| | - Maria Barile
- Istituto di Biomembrane e Bioenergetica, CNR, Via Orabona 4, 70126 Bari, Italy
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università degli Studi di Bari “Aldo Moro”, Via Orabona 4, 70126 Bari, Italy
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29
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Giancaspero TA, Busco G, Panebianco C, Carmone C, Miccolis A, Liuzzi GM, Colella M, Barile M. FAD synthesis and degradation in the nucleus create a local flavin cofactor pool. J Biol Chem 2013; 288:29069-80. [PMID: 23946482 DOI: 10.1074/jbc.m113.500066] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
FAD is a redox cofactor ensuring the activity of many flavoenzymes mainly located in mitochondria but also relevant for nuclear redox activities. The last enzyme in the metabolic pathway producing FAD is FAD synthase (EC 2.7.7.2), a protein known to be localized both in cytosol and in mitochondria. FAD degradation to riboflavin occurs via still poorly characterized enzymes, possibly belonging to the NUDIX hydrolase family. By confocal microscopy and immunoblotting experiments, we demonstrate here the existence of FAD synthase in the nucleus of different experimental rat models. HPLC experiments demonstrated that isolated rat liver nuclei contain ∼300 pmol of FAD·mg(-1) protein, which was mainly protein-bound FAD. A mean FAD synthesis rate of 18.1 pmol·min(-1)·mg(-1) protein was estimated by both HPLC and continuous coupled enzymatic spectrophotometric assays. Rat liver nuclei were also shown to be endowed with a FAD pyrophosphatase that hydrolyzes FAD with an optimum at alkaline pH and is significantly inhibited by adenylate-containing nucleotides. The coordinate activity of these FAD forming and degrading enzymes provides a potential mechanism by which a dynamic pool of flavin cofactor is created in the nucleus. These data, which significantly add to the biochemical comprehension of flavin metabolism and its subcellular compartmentation, may also provide the basis for a more detailed comprehension of the role of flavin homeostasis in biologically and clinically relevant epigenetic events.
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30
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Kim HJ, Winge DR. Emerging concepts in the flavinylation of succinate dehydrogenase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:627-36. [PMID: 23380393 DOI: 10.1016/j.bbabio.2013.01.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 01/14/2013] [Accepted: 01/18/2013] [Indexed: 12/28/2022]
Abstract
The Succinate Dehydrogenase (SDH) heterotetrameric complex catalyzes the oxidation of succinate to fumarate in the tricarboxylic acid (TCA) cycle and in the aerobic respiratory chains of eukaryotes and bacteria. Essential in this catalysis is the covalently-linked cofactor flavin adenine dinucleotide (FAD) in subunit1 (Sdh1) of the SDH enzyme complex. The mechanism of FAD insertion and covalent attachment to Sdh1 is unknown. Our working concept of this flavinylation process has relied mostly on foundational works from the 1990s and by applying the principles learned from other enzymes containing a similarly linked FAD. The discovery of the flavinylation factor Sdh5, however, has provided new insight into the possible mechanism associated with Sdh1 flavinylation. This review focuses on encapsulating prior and recent advances towards understanding the mechanism associated with flavinylation of Sdh1 and how this flavinylation process affects the overall assembly of SDH. This article is part of a Special Issue entitled: Respiratory complex II: Role in cellular physiology and disease.
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Affiliation(s)
- Hyung J Kim
- Department of Medicine and Biochemistry, University of Utah Health Sciences Center, Salt Lake City, UT 84132, USA
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31
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Role of key residues at the flavin mononucleotide (FMN):adenylyltransferase catalytic site of the bifunctional riboflavin kinase/flavin adenine dinucleotide (FAD) Synthetase from Corynebacterium ammoniagenes. Int J Mol Sci 2012. [PMID: 23203077 PMCID: PMC3509593 DOI: 10.3390/ijms131114492] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
In mammals and in yeast the conversion of Riboflavin (RF) into flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) is catalysed by the sequential action of two enzymes: an ATP:riboflavin kinase (RFK) and an ATP:FMN adenylyltransferase (FMNAT). However, most prokaryotes depend on a single bifunctional enzyme, FAD synthetase (FADS), which folds into two modules: the C-terminal associated with RFK activity and the N-terminal associated with FMNAT activity. Sequence and structural analysis suggest that the 28-HxGH-31, 123-Gx(D/N)-125 and 161-xxSSTxxR-168 motifs from FADS must be involved in ATP stabilisation for the adenylylation of FMN, as well as in FAD stabilisation for FAD phyrophosphorolysis. Mutants were produced at these motifs in the Corynebacterium ammoniagenes FADS (CaFADS). Their effects on the kinetic parameters of CaFADS activities (RFK, FMNAT and FAD pyrophosphorilase), and on substrates and product binding properties indicate that H28, H31, N125 and S164 contribute to the geometry of the catalytically competent complexes at the FMNAT-module of CaFADS.
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Arabidopsis RIBA proteins: two out of three isoforms have lost their bifunctional activity in riboflavin biosynthesis. Int J Mol Sci 2012. [PMID: 23203051 PMCID: PMC3509567 DOI: 10.3390/ijms131114086] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Riboflavin serves as a precursor for flavocoenzymes (FMN and FAD) and is essential for all living organisms. The two committed enzymatic steps of riboflavin biosynthesis are performed in plants by bifunctional RIBA enzymes comprised of GTP cyclohydrolase II (GCHII) and 3,4-dihydroxy-2-butanone-4-phosphate synthase (DHBPS). Angiosperms share a small RIBA gene family consisting of three members. A reduction of AtRIBA1 expression in the Arabidopsis rfd1mutant and in RIBA1 antisense lines is not complemented by the simultaneously expressed isoforms AtRIBA2 and AtRIBA3. The intensity of the bleaching leaf phenotype of RIBA1 deficient plants correlates with the inactivation of AtRIBA1 expression, while no significant effects on the mRNA abundance of AtRIBA2 and AtRIBA3 were observed. We examined reasons why both isoforms fail to sufficiently compensate for a lack of RIBA1 expression. All three RIBA isoforms are shown to be translocated into chloroplasts as GFP fusion proteins. Interestingly, both AtRIBA2 and AtRIBA3 have amino acid exchanges in conserved peptides domains that have been found to be essential for the two enzymatic functions. In vitro activity assays of GCHII and DHBPS with all of the three purified recombinant AtRIBA proteins and complementation of E. coli ribA and ribB mutants lacking DHBPS and GCHII expression, respectively, confirmed the loss of bifunctionality for AtRIBA2 and AtRIBA3. Phylogenetic analyses imply that the monofunctional, bipartite RIBA3 proteins, which have lost DHBPS activity, evolved early in tracheophyte evolution.
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Gerdes S, Lerma-Ortiz C, Frelin O, Seaver SMD, Henry CS, de Crécy-Lagard V, Hanson AD. Plant B vitamin pathways and their compartmentation: a guide for the perplexed. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:5379-95. [PMID: 22915736 DOI: 10.1093/jxb/ers208] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The B vitamins and the cofactors derived from them are essential for life. B vitamin synthesis in plants is consequently as crucial to plants themselves as it is to humans and animals, whose B vitamin nutrition depends largely on plants. The synthesis and salvage pathways for the seven plant B vitamins are now broadly known, but certain enzymes and many transporters have yet to be identified, and the subcellular locations of various reactions are unclear. Although very substantial, what is not known about plant B vitamin pathways is regrettably difficult to discern from the literature or from biochemical pathway databases. Nor do databases accurately represent all that is known about B vitamin pathways-above all their compartmentation-because the facts are scattered throughout the literature, and thus hard to piece together. These problems (i) deter discoveries because newcomers to B vitamins cannot see which mysteries still need solving; and (ii) impede metabolic reconstruction and modelling of B vitamin pathways because genes for reactions or transport steps are missing. This review therefore takes a fresh approach to capture current knowledge of B vitamin pathways in plants. The synthesis pathways, key salvage routes, and their subcellular compartmentation are surveyed in depth, and encoded in the SEED database (http://pubseed.theseed.org/seedviewer.cgi?page=PlantGateway) for Arabidopsis and maize. The review itself and the encoded pathways specifically identify enigmatic or missing reactions, enzymes, and transporters. The SEED-encoded B vitamin pathway collection is a publicly available, expertly curated, one-stop resource for metabolic reconstruction and modeling.
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Affiliation(s)
- Svetlana Gerdes
- Mathematics and Computer Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 USA
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Silencing of FAD synthase gene in Caenorhabditis elegans upsets protein homeostasis and impacts on complex behavioral patterns. Biochim Biophys Acta Gen Subj 2012; 1820:521-31. [PMID: 22306247 DOI: 10.1016/j.bbagen.2012.01.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 01/18/2012] [Accepted: 01/22/2012] [Indexed: 12/29/2022]
Abstract
BACKGROUND FAD synthase is a ubiquitous enzyme that catalyses the last step of FAD biosynthesis, allowing for the biogenesis of several flavoproteins. In humans different isoforms are generated by alternative splicing, isoform 1 being localized in mitochondria. Homology searching in Caenorabditis elegans leads to the identification of two human FAD synthase homologues, coded by the single copy gene R53.1. METHODS The C. elegans R53.1 gene was silenced by feeding. The expression level of transcripts was established by semi-quantitative RT-PCR. Overall protein composition was evaluated by two-dimensional electrophoresis. Enzymatic activities were measured by spectrophotometry and oxygen consumption by polarography on isolated mitochondria. RESULTS From R53.1 two transcripts are generated by trans-splicing. Reducing by 50% the transcription efficiency of R53.1 by RNAi results in a 50% reduction in total flavin with decrease in ATP content and increase in ROS level. Significant phenotypical changes are noticed in knock-down nematodes. Among them, a significant impairment in locomotion behaviour possibly due to altered cholinergic transmission. At biochemical level, impairment of flavoenzyme activities and of some KCN-insensitive oxygen-consuming enzymes is detected. At proteomic level, at least 15 abundant proteins are affected by R53.1 gene silencing, among which superoxide dismutases. CONCLUSION AND GENERAL SIGNIFICANCE For the first time we addressed the existence of different isoforms of FAD-metabolizing enzymes in nematodes. A correlation between FAD synthase silencing and flavoenzyme derangement, energy shortage and redox balance impairment is apparent. In this aspect R53.1-interfered nematodes could provide an animal model system for studying human pathologies with alteration in flavin homeostasis/flavoenzyme biogenesis.
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Hedtke B, Alawady A, Albacete A, Kobayashi K, Melzer M, Roitsch T, Masuda T, Grimm B. Deficiency in riboflavin biosynthesis affects tetrapyrrole biosynthesis in etiolated Arabidopsis tissue. PLANT MOLECULAR BIOLOGY 2012; 78:77-93. [PMID: 22081402 DOI: 10.1007/s11103-011-9846-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Accepted: 10/29/2011] [Indexed: 05/03/2023]
Abstract
Tetrapyrrole biosynthesis is controlled by multiple environmental and endogenous cues. Etiolated T-DNA insertion mutants were screened for red fluorescence as result of elevated levels of protochlorophyllide and four red fluorescent in the dark (rfd) mutants were isolated and identified. rfd3 and rfd4 belong to the group of photomorphogenic cop/det/fus mutants. rfd1 and rfd2 had genetic lesions in RIBA1 and FLU encoding the dual-functional protein GTP cyclohydrolase II/3,4-dihydroxy-2-butanone-4-phosphate synthase and a negative regulator of tetrapyrrole biosynthesis, respectively. RIBA1 catalyses the initial reaction of the metabolic pathway of riboflavin biosynthesis and rfd1 contains reduced contents of riboflavin and the flavo-coenzymes FMN and FAD. Transcriptome analysis of rfd1 revealed up-regulated genes encoding nucleus-localized factors involved in cytokinin signalling and numerous down-regulated LEA genes as well as an auxin-inducible GH3 gene. Alteration of cytokinin metabolism of rfd1was confirmed by elevated contents of active forms of cytokinin and stimulated expression of an ARR6::GUS reporter construct. An etiolated quadruple ckx (cytokinin oxidase) mutant with impaired cytokinin degradation as well as different knockout mutants for the negative AUX/IAA regulators shy2-101 (iaa3), axr2-1 (iaa7) and slr-1 (iaa14) showed also excessive protochlorophyllide accumulation. The transcript levels of CHLH and HEMA1 encoding Mg chelatase and glutamyl-tRNA reductase were increased in rfd1 and the AUX/IAA loss-of-function mutants. It is proposed that reduced riboflavin synthesis impairs the activity of the flavin-containing cytokinin oxidase, increases cytokinin contents and de-represses synthesis of 5-aminolevulinic acid of tetrapyrrole metabolism in darkness. As result of the mutant analyses, the antagonistic cytokinin and auxin signalling is required for a balanced tetrapyrrole biosynthesis in the dark.
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Affiliation(s)
- Boris Hedtke
- Institute of Biology/Plant Physiology, Humboldt University Berlin, Berlin, Germany
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Rawat R, Sandoval FJ, Wei Z, Winkler R, Roje S. An FMN hydrolase of the haloacid dehalogenase superfamily is active in plant chloroplasts. J Biol Chem 2011; 286:42091-42098. [PMID: 22002057 PMCID: PMC3234908 DOI: 10.1074/jbc.m111.260885] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 10/13/2011] [Indexed: 11/06/2022] Open
Abstract
FMN hydrolases catalyze dephosphorylation of FMN to riboflavin. Although these enzymes have been described in many organisms, few had their corresponding genes cloned and their recombinant proteins biochemically characterized, and none had their physiological roles determined. We found previously that FMN hydrolase activity in pea chloroplasts is Mg(2+)-dependent, suggesting an enzyme of the haloacid dehalogenase (HAD) superfamily. In this study, a new FMN hydrolase was purified by multistep chromatography after ammonium sulfate precipitation. The molecular weight of the native protein was estimated at ∼59,400, a dimer of about twice the predicted molecular weight of most HAD superfamily phosphatases. After SDS-PAGE of the partially purified material, two separate protein bands within 25-30 kDa were extracted from the gel and analyzed by nanoLC-MS/MS. Peptide sequence matching to the protein samples suggested the presence of three HAD-like hydrolases. cDNAs for sequence homologs from Arabidopsis thaliana of these proteins were expressed in Escherichia coli. Activity screening of the encoded proteins showed that the At1g79790 gene encodes an FMN hydrolase (AtcpFHy1). Plastid localization of AtcpFHy1 was confirmed using fluorescence microscopy of A. thaliana protoplasts transiently expressing the N-terminal fusion of AtcpFHy1 to enhanced green fluorescent protein. Phosphatase activity of AtcpFHy1 is FMN-specific, as assayed with 19 potential substrates. Kinetic parameters and pH and temperature optima for AtcpFHy1 were determined. A phylogenetic analysis of putative phosphatases of the HAD superfamily suggested distinct evolutionary origins for the plastid AtcpFHy1 and the cytosolic FMN hydrolase characterized previously.
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Affiliation(s)
- Renu Rawat
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164
| | - Francisco J Sandoval
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164
| | - Zhaoyang Wei
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164
| | - Robert Winkler
- Departamento de Biotecnología y Tecnología de Alimentos, Instituto Tecnológico y de Estudios Superiores de Monterrey, 64849 Monterrey, Nuevo León, Mexico
| | - Sanja Roje
- Institute of Biological Chemistry, Washington State University, Pullman, Washington 99164.
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Torchetti EM, Bonomi F, Galluccio M, Gianazza E, Giancaspero TA, Iametti S, Indiveri C, Barile M. Human FAD synthase (isoform 2): a component of the machinery that delivers FAD to apo-flavoproteins. FEBS J 2011; 278:4434-49. [PMID: 21951714 DOI: 10.1111/j.1742-4658.2011.08368.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A soluble form of human FAD synthase (isoform 2; hFADS2) was produced and purified to homogeneity as a recombinant His-tagged protein. The enzyme binds 1 mole of the FAD product very tightly, although noncovalently. Complete release of FAD from the 'as isolated' protein requires extensive denaturation. A 75 : 25 mixture of apo/holoprotein could be prepared by treatment with mild chaotropes, allowing estimatation of the contribution made by bound FAD to the protein stability and evaluatation of whether structural rearrangements may be required for FAD release. Under turnover conditions, the enzyme catalyzes FAD assembly from ATP and FMN and, at a much lower rate, the pyrophosphorolytic hydrolysis of FAD. Several mechanistic features of both reactions were investigated in detail, along with their dependence on environmental conditions (pH, temperature, dependence on metals). Our data indicate that FAD release may represent the rate-limiting step of the whole catalytic cycle and that the process leading to FAD synthesis, and delivery to client apoproteins may be tightly controlled.
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Affiliation(s)
- Enza M Torchetti
- Dipartimento di Biochimica e Biologia Molecolare E. Quagliariello (DBBM), Università degli Studi di Bari, Bari, Italy
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Di Martino C, Pallotta ML. Mitochondria-localized NAD biosynthesis by nicotinamide mononucleotide adenylyltransferase in Jerusalem artichoke (Helianthus tuberosus L.) heterotrophic tissues. PLANTA 2011; 234:657-670. [PMID: 21598001 DOI: 10.1007/s00425-011-1428-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 04/30/2011] [Indexed: 05/30/2023]
Abstract
Current studies in plants suggest that the content of the coenzyme NAD is variable and potentially important in determining cell fate. In cases that implicate NAD consumption, re-synthesis must occur to maintain dinucleotide pools. Despite information on the pathways involved in NAD synthesis in plants, the existence of a mitochondrial nicotinamide mononucleotide adenylyltransferase (NMNAT) activity which catalyses NAD synthesis from nicotinamide mononucleotide (NMN) and ATP has not been reported. To verify the latter assumed pathway, experiments with purified and bioenergetically active mitochondria prepared from tubers of Jerusalem artichoke (Helianthus tuberosus L.) were performed. To determine whether NAD biosynthesis might occur, NMN was added to Jerusalem artichoke mitochondria (JAM) and NAD biosynthesis was tested by means of HPLC and spectroscopically. Our results indicate that JAM contain a specific NMNAT inhibited by Na-pyrophosphate, AMP and ADP-ribose. The dependence of NAD synthesis rate on NMN concentration shows saturation kinetics with K (m) and V (max) values of 82 ± 1.05 μM and 4.20 ± 0.20 nmol min(-1) mg(-1) protein, respectively. The enzyme's pH and temperature dependence were also investigated. Fractionation studies revealed that mitochondrial NMNAT activity was present in the soluble matrix fraction. The NAD pool needed constant replenishment that might be modulated by environmental inputs. Thus, the mitochondrion in heterotrophic plant tissues ensures NAD biosynthesis by NMNAT activity and helps to orchestrate NAD metabolic network in implementing the survival strategy of cells.
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Affiliation(s)
- Catello Di Martino
- Department of Animal, Plant and Environmental Sciences, University of Molise, Via F. De Sanctis, 86100 Campobasso, Italy
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Deng B, Deng S, Sun F, Zhang S, Dong H. Down-regulation of free riboflavin content induces hydrogen peroxide and a pathogen defense in Arabidopsis. PLANT MOLECULAR BIOLOGY 2011; 77:185-201. [PMID: 21720919 DOI: 10.1007/s11103-011-9802-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2010] [Accepted: 06/08/2011] [Indexed: 05/26/2023]
Abstract
Riboflavin mediates many bioprocesses associated with the generation of hydrogen peroxide (H₂O₂), a cellular signal that regulates defense responses in plants. Although plants can synthesize riboflavin, the levels vary widely in different organs and during different stages of development, indicating that changes in riboflavin levels may have physiological effects. Here, we show that changing riboflavin content affects H₂O₂ accumulation and a pathogen defense in Arabidopsis thaliana. Leaf content of free riboflavin was modulated by ectopic expression of the turtle gene encoding riboflavin-binding protein (RfBP). The RfBP-expressing Arabidopsis thaliana (REAT) plants produced the RfBP protein that possessed riboflavin-binding activity. Compared with the wild-type plant, several tested REAT lines had >70% less flavins of free form. This change accompanied an elevation in the level of H₂O₂ and an enhancement of plant resistance to a bacterial pathogen. All the observed REAT characters were eliminated due to RfBP silencing (RfBPi) under REAT background. When an H₂O₂ scavenger was applied, H₂O₂ level declined in all the plants, and REAT no longer exhibited the phenotype of resistance enhancement. However, treatment with an NADPH oxidase inhibitor diminished H₂O₂ content and pathogen defense in wild-type and RfBPi but not in REAT. Our results suggest that the intrinsic down-regulation of free flavins is responsible for NADPH oxidase-independent H₂O₂ accumulation and the pathogen defense.
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Affiliation(s)
- Benliang Deng
- State Ministry of Education Key Laboratory of Integrated Management of Crop Pests, Nanjing Agricultural University, Nanjing 210095, China
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Abbas CA, Sibirny AA. Genetic control of biosynthesis and transport of riboflavin and flavin nucleotides and construction of robust biotechnological producers. Microbiol Mol Biol Rev 2011; 75:321-60. [PMID: 21646432 PMCID: PMC3122625 DOI: 10.1128/mmbr.00030-10] [Citation(s) in RCA: 243] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Riboflavin [7,8-dimethyl-10-(1'-d-ribityl)isoalloxazine, vitamin B₂] is an obligatory component of human and animal diets, as it serves as the precursor of flavin coenzymes, flavin mononucleotide, and flavin adenine dinucleotide, which are involved in oxidative metabolism and other processes. Commercially produced riboflavin is used in agriculture, medicine, and the food industry. Riboflavin synthesis starts from GTP and ribulose-5-phosphate and proceeds through pyrimidine and pteridine intermediates. Flavin nucleotides are synthesized in two consecutive reactions from riboflavin. Some microorganisms and all animal cells are capable of riboflavin uptake, whereas many microorganisms have distinct systems for riboflavin excretion to the medium. Regulation of riboflavin synthesis in bacteria occurs by repression at the transcriptional level by flavin mononucleotide, which binds to nascent noncoding mRNA and blocks further transcription (named the riboswitch). In flavinogenic molds, riboflavin overproduction starts at the stationary phase and is accompanied by derepression of enzymes involved in riboflavin synthesis, sporulation, and mycelial lysis. In flavinogenic yeasts, transcriptional repression of riboflavin synthesis is exerted by iron ions and not by flavins. The putative transcription factor encoded by SEF1 is somehow involved in this regulation. Most commercial riboflavin is currently produced or was produced earlier by microbial synthesis using special selected strains of Bacillus subtilis, Ashbya gossypii, and Candida famata. Whereas earlier RF overproducers were isolated by classical selection, current producers of riboflavin and flavin nucleotides have been developed using modern approaches of metabolic engineering that involve overexpression of structural and regulatory genes of the RF biosynthetic pathway as well as genes involved in the overproduction of the purine precursor of riboflavin, GTP.
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Affiliation(s)
| | - Andriy A. Sibirny
- Institute of Cell Biology, NAS of Ukraine, Lviv 79005, Ukraine
- University of Rzeszow, Rzeszow 35-601, Poland
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Ouyang M, Ma J, Zou M, Guo J, Wang L, Lu C, Zhang L. The photosensitive phs1 mutant is impaired in the riboflavin biogenesis pathway. JOURNAL OF PLANT PHYSIOLOGY 2010; 167:1466-1476. [PMID: 20580123 DOI: 10.1016/j.jplph.2010.05.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2010] [Revised: 05/17/2010] [Accepted: 05/19/2010] [Indexed: 05/27/2023]
Abstract
A photosensitive (phs1) mutant of Arabidopsis thaliana was isolated and characterized. The PHS1 gene was cloned using a map-based approach. The gene was found to encode a protein containing a deaminase-reductase domain that is involved in the riboflavin pathway. The phenotype and growth of the phs1 mutant were comparable to that of the wild-type when the plants were grown under low light conditions. When the light intensity was increased, the mutant was characterized by stunted growth and bleached leaves as well as a decrease in FNR activity. The NADPH levels declined, whereas the NADP(+) levels increased, leading to a decrease in the NADPH/NADP(+) ratio. The mutant suffered from severe photooxidative damage with an increase in antioxidant enzyme activity and a drastic reduction in the levels of chlorophyll and photosynthetic proteins. Supplementing the mutant with exogenous FAD rescued the photosensitive phenotype, even under increasing light intensity. The riboflavin pathway therefore plays an important role in protecting plants from photooxidative damage.
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Affiliation(s)
- Min Ouyang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
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Evolutionary divergence of chloroplast FAD synthetase proteins. BMC Evol Biol 2010; 10:311. [PMID: 20955574 PMCID: PMC2972280 DOI: 10.1186/1471-2148-10-311] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Accepted: 10/18/2010] [Indexed: 01/18/2023] Open
Abstract
Background Flavin adenine dinucleotide synthetases (FADSs) - a group of bifunctional enzymes that carry out the dual functions of riboflavin phosphorylation to produce flavin mononucleotide (FMN) and its subsequent adenylation to generate FAD in most prokaryotes - were studied in plants in terms of sequence, structure and evolutionary history. Results Using a variety of bioinformatics methods we have found that FADS enzymes localized to the chloroplasts, which we term as plant-like FADS proteins, are distributed across a variety of green plant lineages and constitute a divergent protein family clearly of cyanobacterial origin. The C-terminal module of these enzymes does not contain the typical riboflavin kinase active site sequence, while the N-terminal module is broadly conserved. These results agree with a previous work reported by Sandoval et al. in 2008. Furthermore, our observations and preliminary experimental results indicate that the C-terminus of plant-like FADS proteins may contain a catalytic activity, but different to that of their prokaryotic counterparts. In fact, homology models predict that plant-specific conserved residues constitute a distinct active site in the C-terminus. Conclusions A structure-based sequence alignment and an in-depth evolutionary survey of FADS proteins, thought to be crucial in plant metabolism, are reported, which will be essential for the correct annotation of plant genomes and further structural and functional studies. This work is a contribution to our understanding of the evolutionary history of plant-like FADS enzymes, which constitute a new family of FADS proteins whose C-terminal module might be involved in a distinct catalytic activity.
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Torchetti EM, Brizio C, Colella M, Galluccio M, Giancaspero TA, Indiveri C, Roberti M, Barile M. Mitochondrial localization of human FAD synthetase isoform 1. Mitochondrion 2010; 10:263-73. [PMID: 20060505 DOI: 10.1016/j.mito.2009.12.149] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Revised: 12/14/2009] [Accepted: 12/22/2009] [Indexed: 10/20/2022]
Abstract
FAD synthetase or ATP:FMN adenylyl transferase (FADS or FMNAT, EC 2.7.7.2) is a key enzyme in the metabolic pathway that converts riboflavin into the redox cofactor FAD. We face here the still controversial sub-cellular localization of FADS in eukaryotes. First, by western blotting experiments, we confirm the existence in rat liver of different FADS isoforms which are distinct for molecular mass and sub-cellular localization. A cross-reactive band with an apparent molecular mass of 60 kDa on SDS-PAGE is localized in the internal compartments of freshly isolated purified rat liver mitochondria. Recently we have identified two isoforms of FADS in humans, that differ for an extra-sequence of 97 amino acids at the N-terminus, present only in isoform 1 (hFADS1). The first 17 residues of hFADS1 represent a cleavable mitochondrial targeting sequence (by Target-P prediction). The recombinant hFADS1 produced in Escherichia coli showed apparent K(m) and V(max) values for FMN equal to 1.3+/-0.7 microM and 4.4+/-1.3 nmol x min(-1) x mg protein(-1), respectively, and was inhibited by FMN at concentration higher than 1.5 microM. The in vitro synthesized hFADS1, but not hFADS2, is imported into rat liver mitochondria and processed into a lower molecular mass protein product. Immunofluorescence confocal microscopy performed on BHK-21 and Caco-2 cell lines transiently expressing the two human isoforms, definitively confirmed that hFADS1, but not hFADS2, localizes in mitochondria.
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Affiliation(s)
- Enza Maria Torchetti
- Dipartimento di Biochimica e Biologia Molecolare E. Quagliariello, Università degli Studi di Bari, Via Orabona 4, I-70126 Bari, Italy.
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Herguedas B, Martínez-Júlvez M, Frago S, Medina M, Hermoso JA. Crystallization and preliminary X-ray diffraction studies of FAD synthetase from Corynebacterium ammoniagenes. Acta Crystallogr Sect F Struct Biol Cryst Commun 2009; 65:1285-8. [PMID: 20054130 PMCID: PMC2802882 DOI: 10.1107/s1744309109044789] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2009] [Accepted: 10/27/2009] [Indexed: 11/10/2022]
Abstract
FAD synthetase from Corynebacterium ammoniagenes (CaFADS), a prokaryotic bifunctional enzyme that catalyses the phosphorylation of riboflavin as well as the adenylylation of FMN, has been crystallized using the hanging-drop vapour-diffusion method at 277 K. Diffraction-quality cubic crystals of native and selenomethionine-labelled (SeMet-CaFADS) protein belonged to the cubic space group P2(1)3, with unit-cell parameters a = b = c = 133.47 A and a = b = c = 133.40 A, respectively. Data sets for native and SeMet-containing crystals were collected to 1.95 and 2.42 A resolution, respectively.
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Affiliation(s)
- Beatriz Herguedas
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, and Institute of Biocomputation and Physics of Complex Systems, Universidad de Zaragoza, 50009 Zaragoza, Spain
- Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto de Química-Física ‘Rocasolano’, Consejo Superior de Investigaciones Científicas, Serrano 119, 28006 Madrid, Spain
| | - Marta Martínez-Júlvez
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, and Institute of Biocomputation and Physics of Complex Systems, Universidad de Zaragoza, 50009 Zaragoza, Spain
| | - Susana Frago
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, and Institute of Biocomputation and Physics of Complex Systems, Universidad de Zaragoza, 50009 Zaragoza, Spain
| | - Milagros Medina
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, and Institute of Biocomputation and Physics of Complex Systems, Universidad de Zaragoza, 50009 Zaragoza, Spain
| | - Juan A. Hermoso
- Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto de Química-Física ‘Rocasolano’, Consejo Superior de Investigaciones Científicas, Serrano 119, 28006 Madrid, Spain
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Frago S, Velázquez-Campoy A, Medina M. The puzzle of ligand binding to Corynebacterium ammoniagenes FAD synthetase. J Biol Chem 2009; 284:6610-9. [PMID: 19136717 PMCID: PMC2652324 DOI: 10.1074/jbc.m808142200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2008] [Revised: 12/11/2008] [Indexed: 11/06/2022] Open
Abstract
In bacteria, riboflavin phosphorylation and subsequent conversion of FMN into FAD are carried out by FAD synthetase, a single bifunctional enzyme. Both reactions require ATP and Mg(2+). The N-terminal domain of FAD synthetase appears to be responsible for the adenylyltransferase activity, whereas the C-terminal domain would be in charge of the kinase activity. Binding to Corynebacterium ammoniagenes FAD synthetase of its products and substrates, as well as of several analogues, is analyzed. Binding parameters for adenine nucleotides to each one of the two adenine nucleotide sites are reported. In addition, it is demonstrated for the first time that the enzyme presents two independent flavin sites, each one related with one of the enzymatic activities. The binding parameters of flavins to these sites are also provided. The presence of Mg(2+) and of both adenine nucleotides and flavins cooperatively modulates the interaction parameters for the other ligands. Our data also suggest that during its double catalytic cycle FAD synthetase must suffer conformational changes induced by adenine nucleotide-Mg(2+) or flavin binding. They might include not only rearrangement of the different protein loops but also alternative conformations between domains.
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Affiliation(s)
- Susana Frago
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, and Institute of Biocomputation and Physics of Complex Systems
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