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Lázaro-Antón L, Veiga-da-Cunha M, Elizalde-Bielsa A, Chevalier N, Conde-Álvarez R, Iriarte M, Letesson JJ, Moriyón I, Van Schaftingen E, Zúñiga-Ripa A. A novel gluconeogenic route enables efficient use of erythritol in zoonotic Brucella. Front Vet Sci 2024; 11:1328293. [PMID: 38601913 PMCID: PMC11005471 DOI: 10.3389/fvets.2024.1328293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 01/29/2024] [Indexed: 04/12/2024] Open
Abstract
Brucellosis is a worldwide extended zoonosis caused by pathogens of the genus Brucella. While most B. abortus, B. melitensis, and B. suis biovars grow slowly in complex media, they multiply intensely in livestock genitals and placenta indicating high metabolic capacities. Mutant analyses in vitro and in infection models emphasize that erythritol (abundant in placenta and genitals) is a preferred substrate of brucellae, and suggest hexoses, pentoses, and gluconeogenic substrates use in host cells. While Brucella sugar and erythritol catabolic pathways are known, growth on 3-4 carbon substrates persists in Fbp- and GlpX-deleted mutants, the canonical gluconeogenic fructose 1,6-bisphosphate (F1,6bP) bisphosphatases. Exploiting the prototrophic and fast-growing properties of B. suis biovar 5, we show that gluconeogenesis requires fructose-bisphosphate aldolase (Fba); the existence of a novel broad substrate bisphosphatase (Bbp) active on sedoheptulose 1,7-bisphosphate (S1,7bP), F1,6bP, and other phosphorylated substrates; that Brucella Fbp unexpectedly acts on S1,7bP and F1,6bP; and that, while active in B. abortus and B. melitensis, GlpX is disabled in B. suis biovar 5. Thus, two Fba-dependent reactions (dihydroxyacetone-phosphate + glyceraldehyde 3-phosphate ⇌ F1,6bP; and dihydroxyacetone-phosphate + erythrose 4-phosphate ⇌ S1,7bP) can, respectively, yield fructose 6-phosphate and sedoheptulose 7-phosphate for classical gluconeogenesis and the Pentose Phosphate Shunt (PPS), the latter reaction opening a new gluconeogenic route. Since erythritol generates the PPS-intermediate erythrose 4-phosphate, and the Fba/Fbp-Bbp route predicts sedoheptulose 7-phosphate generation from erythrose 4-phosphate, we re-examined the erythritol connections with PPS. Growth on erythritol required transaldolase or the Fba/Fbp-Bbp pathway, strongly suggesting that Fba/Fbp-Bbp works as a PPS entry for both erythritol and gluconeogenic substrates in Brucella. We propose that, by increasing erythritol channeling into PPS through these peculiar routes, brucellae proliferate in livestock genitals and placenta in the high numbers that cause abortion and infertility, and make brucellosis highly contagious. These findings could be the basis for developing attenuated brucellosis vaccines safer in pregnant animals.
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Affiliation(s)
- Leticia Lázaro-Antón
- Departamento de Microbiología y Parasitología – IDISNA, Universidad de Navarra, Pamplona, Spain
| | - Maria Veiga-da-Cunha
- Groupe de Recherches Metaboliques, De Duve Institute, UCLouvain, Brussels, Belgium
| | - Aitor Elizalde-Bielsa
- Departamento de Microbiología y Parasitología – IDISNA, Universidad de Navarra, Pamplona, Spain
| | - Nathalie Chevalier
- Groupe de Recherches Metaboliques, De Duve Institute, UCLouvain, Brussels, Belgium
| | - Raquel Conde-Álvarez
- Departamento de Microbiología y Parasitología – IDISNA, Universidad de Navarra, Pamplona, Spain
| | - Maite Iriarte
- Departamento de Microbiología y Parasitología – IDISNA, Universidad de Navarra, Pamplona, Spain
| | | | - Ignacio Moriyón
- Departamento de Microbiología y Parasitología – IDISNA, Universidad de Navarra, Pamplona, Spain
| | | | - Amaia Zúñiga-Ripa
- Departamento de Microbiología y Parasitología – IDISNA, Universidad de Navarra, Pamplona, Spain
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2
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Kovářová J, Moos M, Barrett MP, Horn D, Zíková A. The bloodstream form of Trypanosoma brucei displays non-canonical gluconeogenesis. PLoS Negl Trop Dis 2024; 18:e0012007. [PMID: 38394337 PMCID: PMC10917290 DOI: 10.1371/journal.pntd.0012007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 03/06/2024] [Accepted: 02/16/2024] [Indexed: 02/25/2024] Open
Abstract
Trypanosoma brucei is a causative agent of the Human and Animal African Trypanosomiases. The mammalian stage parasites infect various tissues and organs including the bloodstream, central nervous system, skin, adipose tissue and lungs. They rely on ATP produced in glycolysis, consuming large amounts of glucose, which is readily available in the mammalian host. In addition to glucose, glycerol can also be used as a source of carbon and ATP and as a substrate for gluconeogenesis. However, the physiological relevance of glycerol-fed gluconeogenesis for the mammalian-infective life cycle forms remains elusive. To demonstrate its (in)dispensability, first we must identify the enzyme(s) of the pathway. Loss of the canonical gluconeogenic enzyme, fructose-1,6-bisphosphatase, does not abolish the process hence at least one other enzyme must participate in gluconeogenesis in trypanosomes. Using a combination of CRISPR/Cas9 gene editing and RNA interference, we generated mutants for four enzymes potentially capable of contributing to gluconeogenesis: fructose-1,6-bisphoshatase, sedoheptulose-1,7-bisphosphatase, phosphofructokinase and transaldolase, alone or in various combinations. Metabolomic analyses revealed that flux through gluconeogenesis was maintained irrespective of which of these genes were lost. Our data render unlikely a previously hypothesised role of a reverse phosphofructokinase reaction in gluconeogenesis and preclude the participation of a novel biochemical pathway involving transaldolase in the process. The sustained metabolic flux in gluconeogenesis in our mutants, including a triple-null strain, indicates the presence of a unique enzyme participating in gluconeogenesis. Additionally, the data provide new insights into gluconeogenesis and the pentose phosphate pathway, and improve the current understanding of carbon metabolism of the mammalian-infective stages of T. brucei.
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Affiliation(s)
- Julie Kovářová
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Martin Moos
- Institute of Entomology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Michael P. Barrett
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
| | - David Horn
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee, United Kingdom
| | - Alena Zíková
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
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3
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Zhu W, Chu H, Zhang Y, Luo T, Yu H, Zhu H, Liu Y, Gao H, Zhao Y, Li Q, Wang X, Li G, Yang W. Fructose-1,6-bisphosphatase 1 dephosphorylates IκBα and suppresses colorectal tumorigenesis. Cell Res 2023; 33:245-257. [PMID: 36646759 PMCID: PMC9977772 DOI: 10.1038/s41422-022-00773-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 12/26/2022] [Indexed: 01/18/2023] Open
Abstract
Emerging evidence demonstrates that some metabolic enzymes that phosphorylate soluble metabolites can also phosphorylate a variety of protein substrates as protein kinases to regulate cell cycle, apoptosis and many other fundamental cellular processes. However, whether a metabolic enzyme dephosphorylates protein as a protein phosphatase remains unknown. Here we reveal the gluconeogenic enzyme fructose 1,6-biphosphatase 1 (FBP1) that catalyzes the hydrolysis of fructose 1,6-bisphosphate (F-1,6-BP) to fructose 6-phosphate (F-6-P) as a protein phosphatase by performing a high-throughput screening of metabolic phosphatases with molecular docking followed by molecular dynamics (MD) simulations. Moreover, we identify IκBα as the substrate of FBP1-mediated dephosphorylation by performing phosphoproteomic analysis. Mechanistically, FBP1 directly interacts with and dephosphorylates the serine (S) 32/36 of IκBα upon TNFα stimulation, thereby inhibiting NF-κB activation. MD simulations indicate that the catalytic mechanism of FBP1-mediated IκBα dephosphorylation is similar to F-1,6-BP dephosphorylation, except for higher energetic barriers for IκBα dephosphorylation. Functionally, FBP1-dependent NF-κB inactivation suppresses colorectal tumorigenesis by sensitizing tumor cells to inflammatory stresses and preventing the mobilization of myeloid-derived suppressor cells. Our finding reveals a previously unrecognized role of FBP1 as a protein phosphatase and establishes the critical role of FBP1-mediated IκBα dephosphorylation in colorectal tumorigenesis.
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Affiliation(s)
- Wencheng Zhu
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Huiying Chu
- Laboratory of Molecular Modeling, State Key Lab of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, China
| | - Yajuan Zhang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Tianhang Luo
- Department of General Surgery, Changhai Hospital, The Second Military Medical University, Shanghai, China
| | - Hua Yu
- Precise Genome Engineering Center, School of Life Sciences, Guangzhou University, Guangzhou, Guangdong, China
| | - Hongwen Zhu
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Ye Liu
- Laboratory of Molecular Modeling, State Key Lab of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, China
| | - Hong Gao
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Yun Zhao
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Sciences, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang, China
| | - Quanlin Li
- Endoscopy Center and Endoscopy Research Institute, Zhongshan Hospital, Fudan University, Shanghai, China.
| | - Xiongjun Wang
- Precise Genome Engineering Center, School of Life Sciences, Guangzhou University, Guangzhou, Guangdong, China.
| | - Guohui Li
- Laboratory of Molecular Modeling, State Key Lab of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, China.
| | - Weiwei Yang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China.
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Sciences, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, Zhejiang, China.
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4
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Szabó K, Miskei M, Farkas I, Dombrádi V. The phosphatome of opportunistic pathogen Candida species. FUNGAL BIOL REV 2021. [DOI: 10.1016/j.fbr.2020.12.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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5
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Chen L, Zhao X, He Y, Yang H. Cloning, purification and characterisation of cytosolic fructose-1,6-bisphosphatase from mung bean (Vigna radiata). Food Chem 2021; 347:128973. [PMID: 33444888 DOI: 10.1016/j.foodchem.2020.128973] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 11/26/2020] [Accepted: 12/28/2020] [Indexed: 10/22/2022]
Abstract
To improve the crop yield and quality, the cytosolic fructose-1,6-bisphosphatase (cFBPase) from mung bean (Vigna radiata), a rate-limiting enzyme in gluconeogenesis, was cloned, purified, and structurally characterised. To function it required Mg2+ and Mn2+ at 0.01-10 mM. The Michaelis-Menton constant and adenosine monophosphate (AMP) inhibitory constant (Ki) were 7.96 and 111.09 μM, respectively. The functional site residues of AMP binding (Arg30, Asp32, and Phe33) and the active site residues (Asn218 and Met251) were tested via site-directed mutagenesis and molecular docking. Asn218 and Met251 were replaced by Tyr and Leu, respectively. The M251L mutant showed enhanced substrate affinity and activity, resulting from decreased binding energy (-2.58 kcal·mol-1) and molecular distance (4.2 Å). AMP binding site mutations changed the enzyme activities, indicating a connection between the binding and active sites. Furthermore, Ki and docking analysis revealed that Asp32 plays a key role in maintaining the AMP binding conformation.
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Affiliation(s)
- Lin Chen
- Department of Food Science and Technology, National University of Singapore, Singapore 117542, Singapore; National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Suzhou, Jiangsu 215123, PR China
| | - Xue Zhao
- Department of Food Science and Technology, National University of Singapore, Singapore 117542, Singapore; National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Suzhou, Jiangsu 215123, PR China
| | - Yun He
- Department of Food Science and Technology, National University of Singapore, Singapore 117542, Singapore; National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Suzhou, Jiangsu 215123, PR China
| | - Hongshun Yang
- Department of Food Science and Technology, National University of Singapore, Singapore 117542, Singapore; National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Suzhou, Jiangsu 215123, PR China.
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6
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Pechmann S. Programmed Trade-offs in Protein Folding Networks. Structure 2020; 28:1361-1375.e4. [PMID: 33053320 DOI: 10.1016/j.str.2020.09.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 07/25/2020] [Accepted: 09/23/2020] [Indexed: 12/14/2022]
Abstract
Molecular chaperones as specialized protein quality control enzymes form the core of cellular protein homeostasis. How chaperones selectively interact with their substrate proteins thus allocate their overall limited capacity remains poorly understood. Here, I present an integrated analysis of sequence and structural determinants that define interactions of protein domains as the basic protein folding unit with the Saccharomyces cerevisiae Hsp70 Ssb. Structural homologs of single-domain proteins that differentially interact with Ssb for de novo folding were found to systematically differ in complexity of their folding landscapes, selective use of nonoptimal codons, and presence of short discriminative sequences, thus highlighting pervasive trade-offs in chaperone-assisted protein folding landscapes. However, short discriminative sequences were found to contribute by far the strongest signal toward explaining Ssb interactions. This observation suggested that some chaperone interactions may be directly programmed in the amino acid sequences rather than responding to folding challenges, possibly for regulatory advantages.
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Affiliation(s)
- Sebastian Pechmann
- Département de biochimie, Université de Montréal, 2900 Boulevard Edouard-Montpetit, Montréal, QC H3T 1J4, Canada.
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7
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Ayna A, Moody PCE. Activity of fructose-1,6-bisphosphatase from Campylobacter jejuni. Biochem Cell Biol 2020; 98:518-524. [PMID: 32125881 DOI: 10.1139/bcb-2020-0021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The glycolytic pathway of the enteric pathogen Campylobacter jejuni is incomplete; the absence of phosphofructokinase means that the suppression of futile cycling at this point in the glycolytic-gluconeogenic pathway might not be required, and therefore the mechanism for controlling pathway flux is likely to be quite different or absent. In this study, the characteristics of fructose-1,6-bisphosphatase (FBPase) of C. jejuni are described and the regulation of this enzyme is compared with the equivalent enzymes from organisms capable of glycolysis. The enzyme is insensitive to AMP inhibition, unlike other type I FBPases. Campylobacter jejuni FBPase also shows limited sensitivity to other glycolytic and gluconeogenic intermediates. The allosteric cooperative control of the enzyme's activity found in type I FBPases appears to have been lost.
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Affiliation(s)
- Adnan Ayna
- Department of Chemistry, Faculty of Sciences and Arts, Bingol University, 12000 Bingol, Turkey
| | - Peter C E Moody
- Leicester Institute of Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Leicester, LE1 7RH, UK
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8
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Fructose 1,6- bisphosphatase: getting the message across. Biosci Rep 2019; 39:BSR20190124. [PMID: 30804231 PMCID: PMC6400660 DOI: 10.1042/bsr20190124] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 02/19/2019] [Accepted: 02/25/2019] [Indexed: 02/07/2023] Open
Abstract
Fructose 1,6-bisphosphatase (FBPase) is a key enzyme in gluconeogenesis. It is a potential drug target in the treatment of type II diabetes. The protein is also associated with a rare inherited metabolic disease and some cancer cells lack FBPase activity which promotes glycolysis facilitating the Warburg effect. Thus, there is interest in both inhibiting the enzyme (for diabetes treatment) and restoring its activity (in relevant cancers). The mammalian enzyme is tetrameric, competitively inhibited by Fructose 2,6-bisphosphate and negatively allosterically regulated by AMP. This allosteric regulation requires information transmission between the AMP binding site and the active site of the enzyme. A recent paper by Topaz et al. (Bioscience Reports (2019) 39, pii:BSR20180960) has added additional detail to our understanding of this information transmission process. Two residues in the AMP binding site (Lys112 and Tyr113) were shown to be involved in initiating the message between the two sites. This tyrosine residue has recently be shown to be important with protein’s interaction with the antidiabetic drug metformin. A variant designed to increase metal ion affinity (M248D) resulted in a five-fold increase in enzymatic activity. Interestingly alterations of two residues at the subunit interfaces (Tyr164 and Met177) resulted in increased responsiveness to AMP. Overall, these findings may have implications in the design of novel FBPase inhibitors or activators.
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9
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Gluconeogenesis is essential for trypanosome development in the tsetse fly vector. PLoS Pathog 2018; 14:e1007502. [PMID: 30557412 PMCID: PMC6312356 DOI: 10.1371/journal.ppat.1007502] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 12/31/2018] [Accepted: 12/04/2018] [Indexed: 11/19/2022] Open
Abstract
In the glucose-free environment that is the midgut of the tsetse fly vector, the procyclic form of Trypanosoma brucei primarily uses proline to feed its central carbon and energy metabolism. In these conditions, the parasite needs to produce glucose 6-phosphate (G6P) through gluconeogenesis from metabolism of non-glycolytic carbon source(s). We showed here that two phosphoenolpyruvate-producing enzymes, PEP carboxykinase (PEPCK) and pyruvate phosphate dikinase (PPDK) have a redundant function for the essential gluconeogenesis from proline. Indeed, incorporation of 13C-enriched proline into G6P was abolished in the PEPCK/PPDK null double mutant (Δppdk/Δpepck), but not in the single Δppdk and Δpepck mutant cell lines. The procyclic trypanosome also uses the glycerol conversion pathway to feed gluconeogenesis, since the death of the Δppdk/Δpepck double null mutant in glucose-free conditions is only observed after RNAi-mediated down-regulation of the expression of the glycerol kinase, the first enzyme of the glycerol conversion pathways. Deletion of the gene encoding fructose-1,6-bisphosphatase (Δfbpase), a key gluconeogenic enzyme irreversibly producing fructose 6-phosphate from fructose 1,6-bisphosphate, considerably reduced, but not abolished, incorporation of 13C-enriched proline into G6P. In addition, the Δfbpase cell line is viable in glucose-free conditions, suggesting that an alternative pathway can be used for G6P production in vitro. However, FBPase is essential in vivo, as shown by the incapacity of the Δfbpase null mutant to colonise the fly vector salivary glands, while the parental phenotype is restored in the Δfbpase rescued cell line re-expressing FBPase. The essential role of FBPase for the development of T. brucei in the tsetse was confirmed by taking advantage of an in vitro differentiation assay based on the RNA-binding protein 6 over-expression, in which the procyclic forms differentiate into epimastigote forms but not into mammalian-infective metacyclic parasites. In total, morphology, immunofluorescence and cytometry analyses showed that the differentiation of the epimastigote stages into the metacyclic forms is abolished in the Δfbpase mutant.
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10
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Xu YF, Lu W, Chen JC, Johnson SA, Gibney PA, Thomas DG, Brown G, May AL, Campagna SR, Yakunin AF, Botstein D, Rabinowitz JD. Discovery and Functional Characterization of a Yeast Sugar Alcohol Phosphatase. ACS Chem Biol 2018; 13:3011-3020. [PMID: 30240188 DOI: 10.1021/acschembio.8b00804] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Sugar alcohols (polyols) exist widely in nature. While some specific sugar alcohol phosphatases are known, there is no known phosphatase for some important sugar alcohols (e.g., sorbitol-6-phosphate). Using liquid chromatography-mass spectrometry-based metabolomics, we screened yeast strains with putative phosphatases of unknown function deleted. We show that the yeast gene YNL010W, which has close homologues in all fungi species and some plants, encodes a sugar alcohol phosphatase. We term this enzyme, which hydrolyzes sorbitol-6-phosphate, ribitol-5-phosphate, and (d)-glycerol-3-phosphate, polyol phosphatase 1 or PYP1. Polyol phosphates are structural analogs of the enediol intermediate of phosphoglucose isomerase (Pgi). We find that sorbitol-6-phosphate and ribitol-5-phosphate inhibit Pgi and that Pyp1 activity is important for yeast to maintain Pgi activity in the presence of environmental sugar alcohols. Pyp1 expression is strongly positively correlated with yeast growth rate, presumably because faster growth requires greater glycolytic and accordingly Pgi flux. Thus, yeast express the previously uncharacterized enzyme Pyp1 to prevent inhibition of glycolysis by sugar alcohol phosphates. Pyp1 may be useful for engineering sugar alcohol production.
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Affiliation(s)
- Yi-Fan Xu
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, United States
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Wenyun Lu
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, United States
| | - Jonathan C. Chen
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, United States
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Sarah A. Johnson
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, United States
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Patrick A. Gibney
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, United States
| | - David G. Thomas
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, United States
| | - Greg Brown
- Department of Chemical Engineering and Applied Chemistry, Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Amanda L. May
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Shawn R. Campagna
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Alexander F. Yakunin
- Department of Chemical Engineering and Applied Chemistry, Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - David Botstein
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, United States
- Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, United States
| | - Joshua D. Rabinowitz
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, United States
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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11
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Nocek BP, Khusnutdinova AN, Ruszkowski M, Flick R, Burda M, Batyrova K, Brown G, Mucha A, Joachimiak A, Berlicki Ł, Yakunin AF. Structural Insights into Substrate Selectivity and Activity of Bacterial Polyphosphate Kinases. ACS Catal 2018. [DOI: 10.1021/acscatal.8b03151] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Boguslaw P. Nocek
- Midwest Center for Structural Genomics and Structural Biology Center, Department of Biosciences, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Anna N. Khusnutdinova
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E5, Canada
| | - Milosz Ruszkowski
- Synchrotron Radiation Research Section of MCL, National Cancer Institute, Argonne, Illinois 60439, United States
| | - Robert Flick
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E5, Canada
| | - Malgorzata Burda
- Department of Bioorganic Chemistry, Faculty of Chemistry, Wroclaw University of Science and Technology, 50-370 Wroclaw, Poland
| | - Khorcheska Batyrova
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E5, Canada
| | - Greg Brown
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E5, Canada
| | - Artur Mucha
- Department of Bioorganic Chemistry, Faculty of Chemistry, Wroclaw University of Science and Technology, 50-370 Wroclaw, Poland
| | - Andrzej Joachimiak
- Midwest Center for Structural Genomics and Structural Biology Center, Department of Biosciences, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Łukasz Berlicki
- Department of Bioorganic Chemistry, Faculty of Chemistry, Wroclaw University of Science and Technology, 50-370 Wroclaw, Poland
| | - Alexander F. Yakunin
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON M5S 3E5, Canada
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12
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Ganapathy U, Marrero J, Calhoun S, Eoh H, de Carvalho LPS, Rhee K, Ehrt S. Two enzymes with redundant fructose bisphosphatase activity sustain gluconeogenesis and virulence in Mycobacterium tuberculosis. Nat Commun 2015; 6:7912. [PMID: 26258286 PMCID: PMC4535450 DOI: 10.1038/ncomms8912] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 06/25/2015] [Indexed: 01/23/2023] Open
Abstract
The human pathogen Mycobacterium tuberculosis (Mtb) likely utilizes host fatty acids as a carbon source during infection. Gluconeogenesis is essential for the conversion of fatty acids into biomass. A rate-limiting step in gluconeogenesis is the conversion of fructose 1,6-bisphosphate to fructose 6-phosphate by a fructose bisphosphatase (FBPase). The Mtb genome contains only one annotated FBPase gene, glpX. Here we show that, unexpectedly, an Mtb mutant lacking GLPX grows on gluconeogenic carbon sources and has detectable FBPase activity. We demonstrate that the Mtb genome encodes an alternative FBPase (GPM2, Rv3214) that can maintain gluconeogenesis in the absence of GLPX. Consequently, deletion of both GLPX and GPM2 is required for disruption of gluconeogenesis and attenuation of Mtb in a mouse model of infection. Our work affirms a role for gluconeogenesis in Mtb virulence and reveals previously unidentified metabolic redundancy at the FBPase-catalysed reaction step of the pathway. Mycobacterium tuberculosis feeds on host fatty acids during infection, a process that requires a fructose bisphosphatase (FBPase) enzyme for gluconeogenesis. Here, Ganapathy et al. show that the bacterium has two different FBPases and that this enzymatic activity is required for full virulence.
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Affiliation(s)
- Uday Ganapathy
- Department of Microbiology and Immunology, Weill Cornell Medical College, 413 East 69th Street, New York, New York 10021, USA
| | - Joeli Marrero
- Department of Microbiology and Immunology, Weill Cornell Medical College, 413 East 69th Street, New York, New York 10021, USA
| | - Susannah Calhoun
- Department of Microbiology and Immunology, Weill Cornell Medical College, 413 East 69th Street, New York, New York 10021, USA
| | - Hyungjin Eoh
- Department of Medicine, Weill Cornell Medical College, New York, New York 10021, USA
| | | | - Kyu Rhee
- Department of Medicine, Weill Cornell Medical College, New York, New York 10021, USA
| | - Sabine Ehrt
- Department of Microbiology and Immunology, Weill Cornell Medical College, 413 East 69th Street, New York, New York 10021, USA
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13
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Kuznetsova E, Nocek B, Brown G, Makarova KS, Flick R, Wolf YI, Khusnutdinova A, Evdokimova E, Jin K, Tan K, Hanson AD, Hasnain G, Zallot R, de Crécy-Lagard V, Babu M, Savchenko A, Joachimiak A, Edwards AM, Koonin EV, Yakunin AF. Functional Diversity of Haloacid Dehalogenase Superfamily Phosphatases from Saccharomyces cerevisiae: BIOCHEMICAL, STRUCTURAL, AND EVOLUTIONARY INSIGHTS. J Biol Chem 2015; 290:18678-98. [PMID: 26071590 DOI: 10.1074/jbc.m115.657916] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Indexed: 12/15/2022] Open
Abstract
The haloacid dehalogenase (HAD)-like enzymes comprise a large superfamily of phosphohydrolases present in all organisms. The Saccharomyces cerevisiae genome encodes at least 19 soluble HADs, including 10 uncharacterized proteins. Here, we biochemically characterized 13 yeast phosphatases from the HAD superfamily, which includes both specific and promiscuous enzymes active against various phosphorylated metabolites and peptides with several HADs implicated in detoxification of phosphorylated compounds and pseudouridine. The crystal structures of four yeast HADs provided insight into their active sites, whereas the structure of the YKR070W dimer in complex with substrate revealed a composite substrate-binding site. Although the S. cerevisiae and Escherichia coli HADs share low sequence similarities, the comparison of their substrate profiles revealed seven phosphatases with common preferred substrates. The cluster of secondary substrates supporting significant activity of both S. cerevisiae and E. coli HADs includes 28 common metabolites that appear to represent the pool of potential activities for the evolution of novel HAD phosphatases. Evolution of novel substrate specificities of HAD phosphatases shows no strict correlation with sequence divergence. Thus, evolution of the HAD superfamily combines the conservation of the overall substrate pool and the substrate profiles of some enzymes with remarkable biochemical and structural flexibility of other superfamily members.
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Affiliation(s)
- Ekaterina Kuznetsova
- From the Structural Genomics Consortium, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Boguslaw Nocek
- the Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439
| | - Greg Brown
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Kira S Makarova
- the National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland 20894
| | - Robert Flick
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Yuri I Wolf
- the National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland 20894
| | - Anna Khusnutdinova
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Elena Evdokimova
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Ke Jin
- the Department of Biochemistry, Research and Innovation Centre, University of Regina, Regina, Saskatchewan S4S 0A2, Canada, and
| | - Kemin Tan
- the Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439
| | - Andrew D Hanson
- the Horticultural Sciences Department, Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611
| | - Ghulam Hasnain
- the Horticultural Sciences Department, Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611
| | - Rémi Zallot
- the Horticultural Sciences Department, Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611
| | - Valérie de Crécy-Lagard
- the Horticultural Sciences Department, Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32611
| | - Mohan Babu
- the Department of Biochemistry, Research and Innovation Centre, University of Regina, Regina, Saskatchewan S4S 0A2, Canada, and
| | - Alexei Savchenko
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Andrzej Joachimiak
- the Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439
| | - Aled M Edwards
- From the Structural Genomics Consortium, University of Toronto, Toronto, Ontario M5G 1L7, Canada, the Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439
| | - Eugene V Koonin
- the National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland 20894
| | - Alexander F Yakunin
- the Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada,
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14
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Coker OO, Warit S, Rukseree K, Summpunn P, Prammananan T, Palittapongarnpim P. Functional characterization of two members of histidine phosphatase superfamily in Mycobacterium tuberculosis. BMC Microbiol 2013; 13:292. [PMID: 24330471 PMCID: PMC3866925 DOI: 10.1186/1471-2180-13-292] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 12/07/2013] [Indexed: 01/19/2023] Open
Abstract
Background Functional characterization of genes in important pathogenic bacteria such as Mycobacterium tuberculosis is imperative. Rv2135c, which was originally annotated as conserved hypothetical, has been found to be associated with membrane protein fractions of H37Rv strain. The gene appears to contain histidine phosphatase motif common to both cofactor-dependent phosphoglycerate mutases and acid phosphatases in the histidine phosphatase superfamily. The functions of many of the members of this superfamily are annotated based only on similarity to known proteins using automatic annotation systems, which can be erroneous. In addition, the motif at the N-terminal of Rv2135c is ‘RHA’ unlike ‘RHG’ found in most members of histidine phosphatase superfamily. These necessitate the need for its experimental characterization. The crystal structure of Rv0489, another member of the histidine phosphatase superfamily in M. tuberculosis, has been previously reported. However, its biochemical characteristics remain unknown. In this study, Rv2135c and Rv0489 from M. tuberculosis were cloned and expressed in Escherichia coli with 6 histidine residues tagged at the C terminal. Results Characterization of the purified recombinant proteins revealed that Rv0489 possesses phosphoglycerate mutase activity while Rv2135c does not. However Rv2135c has an acid phosphatase activity with optimal pH of 5.8. Kinetic parameters of Rv2135c and Rv0489 are studied, confirming that Rv0489 is a cofactor dependent phosphoglycerate mutase of M. tuberculosis. Additional characterization showed that Rv2135c exists as a tetramer while Rv0489 as a dimer in solution. Conclusion Most of the proteins orthologous to Rv2135c in other bacteria are annotated as phosphoglycerate mutases or hypothetical proteins. It is possible that they are actually phosphatases. Experimental characterization of a sufficiently large number of bacterial histidine phosphatases will increase the accuracy of the automatic annotation systems towards a better understanding of this important group of enzymes.
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Affiliation(s)
| | | | | | | | | | - Prasit Palittapongarnpim
- Department of Microbiology, Faculty of Science, Mahidol University, Rama 6 Road, Bangkok 10400, Thailand.
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15
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Xu YF, Létisse F, Absalan F, Lu W, Kuznetsova E, Brown G, Caudy AA, Yakunin AF, Broach JR, Rabinowitz JD. Nucleotide degradation and ribose salvage in yeast. Mol Syst Biol 2013; 9:665. [PMID: 23670538 PMCID: PMC4039369 DOI: 10.1038/msb.2013.21] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 04/08/2013] [Indexed: 12/30/2022] Open
Abstract
Nucleotide degradation is a universal metabolic capability. Here we combine metabolomics, genetics and biochemistry to characterize the yeast pathway. Nutrient starvation, via PKA, AMPK/SNF1, and TOR, triggers autophagic breakdown of ribosomes into nucleotides. A protein not previously associated with nucleotide degradation, Phm8, converts nucleotide monophosphates into nucleosides. Downstream steps, which involve the purine nucleoside phosphorylase, Pnp1, and pyrimidine nucleoside hydrolase, Urh1, funnel ribose into the nonoxidative pentose phosphate pathway. During carbon starvation, the ribose-derived carbon accumulates as sedoheptulose-7-phosphate, whose consumption by transaldolase is impaired due to depletion of transaldolase's other substrate, glyceraldehyde-3-phosphate. Oxidative stress increases glyceraldehyde-3-phosphate, resulting in rapid consumption of sedoheptulose-7-phosphate to make NADPH for antioxidant defense. Ablation of Phm8 or double deletion of Pnp1 and Urh1 prevent effective nucleotide salvage, resulting in metabolite depletion and impaired survival of starving yeast. Thus, ribose salvage provides means of surviving nutrient starvation and oxidative stress.
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Affiliation(s)
- Yi-Fan Xu
- Lewis Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA
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16
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Biochemical characterization and functional analysis of fructose-1,6-bisphosphatase from Clonorchis sinensis. Mol Biol Rep 2013; 40:4371-82. [PMID: 23652997 DOI: 10.1007/s11033-013-2508-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Accepted: 04/27/2013] [Indexed: 01/07/2023]
Abstract
Fructose-1,6-bisphosphatase (FBPase), a key regulatory enzyme of gluconeogenesis, plays an essential role in metabolism and development of most organisms. To the wealth of available knowledge about FBPase from Clonorchis sinensis (CsFBPase), in this study, the characteristics of CsFBPase and its potential role in pathogenesis of clonorchiasis were investigated. The Km value of CsFBPase was calculated to be 41.9 uM. The optimal temperature and pH of CsFBPase were 37 °C and pH 7.5-8.0, respectively. In addition, Mg(2+) or K(+) played a regulatory role in enzyme activity of CsFBPase. Both transcriptional and translational level of CsFBPase were higher in metacercariae (one of larva stages) than those in adult worm (P < 0.05). CsFBPase were observed to extensively express in the intestine, vitellaria and tegument of adult worms and ubiquitously in metacercariae. Moreover, CsFBPase was confirmed as a component of excretory/secretory products. Consequently, the translocation of CsFBPase could be detected on epithelial cells of bile duct in liver of C. sinensis infected rat. Recombinant CsFBPase can specifically bind to the membrane of human hepatic stellate cell line LX-2 by immunofluorescence analysis and stimulated proliferation and activation of LX-2 which demonstrated by Cell Counting Kit-8 and upregulation of key fibrosis-related factors, such as α-smooth muscle actin, collagen I and collagen III using qRT-PCR. Thus, we predicated that CsFBPase might be a multifunctional enzyme which played as both regulatory enzyme and virulence factor in pathogenesis of C. sinensis infection.
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Sainz-Polo MA, Lafraya A, Polo A, Marín-Navarro J, Polaina J, Sanz-Aparicio J. Crystallization and preliminary X-ray diffraction analysis of the invertase from Saccharomyces cerevisiae. Acta Crystallogr Sect F Struct Biol Cryst Commun 2012; 68:1538-41. [PMID: 23192042 PMCID: PMC3509983 DOI: 10.1107/s1744309112044417] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 10/25/2012] [Indexed: 11/11/2022]
Abstract
Saccharomyces cerevisiae invertase (ScInv) is an enzyme encoded by the SUC2 gene that releases β-fructose from the nonreducing termini of various β-D-fructofuranoside substrates. Its ability to produce 6-kestose by transglycosylation makes this enzyme an interesting research target for applications in industrial biotechnology. The native enzyme, which presents a high degree of oligomerization, was crystallized by vapour-diffusion methods. The crystals belonged to space group P3(1)21, with unit-cell parameters a=268.6, b=268.6, c=224.4 Å. The crystals diffracted to 3.3 Å resolution and gave complete data sets using a synchrotron X-ray source.
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Affiliation(s)
- M. Angela Sainz-Polo
- Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física ‘Rocasolano’, CSIC, Serrano 119, 28006 Madrid, Spain
| | - Alvaro Lafraya
- Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Paterna, Valencia, Spain
| | - Aitana Polo
- Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física ‘Rocasolano’, CSIC, Serrano 119, 28006 Madrid, Spain
| | - Julia Marín-Navarro
- Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Paterna, Valencia, Spain
| | - Julio Polaina
- Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Paterna, Valencia, Spain
| | - Julia Sanz-Aparicio
- Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física ‘Rocasolano’, CSIC, Serrano 119, 28006 Madrid, Spain
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18
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Structure and activity of the Saccharomyces cerevisiae dUTP pyrophosphatase DUT1, an essential housekeeping enzyme. Biochem J 2011; 437:243-53. [PMID: 21548881 DOI: 10.1042/bj20110304] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Genomes of all free-living organisms encode the enzyme dUTPase (dUTP pyrophosphatase), which plays a key role in preventing uracil incorporation into DNA. In the present paper, we describe the biochemical and structural characterization of DUT1 (Saccharomyces cerevisiae dUTPase). The hydrolysis of dUTP by DUT1 was strictly dependent on a bivalent metal cation with significant activity observed in the presence of Mg2+, Co2+, Mn2+, Ni2+ or Zn2+. In addition, DUT1 showed a significant activity against another potentially mutagenic nucleotide: dITP. With both substrates, DUT1 demonstrated a sigmoidal saturation curve, suggesting a positive co-operativity between the subunits. The crystal structure of DUT1 was solved at 2 Å resolution (1 Å=0.1 nm) in an apo state and in complex with the non-hydrolysable substrate α,β-imido dUTP or dUMP product. Alanine-replacement mutagenesis of the active-site residues revealed seven residues important for activity including the conserved triad Asp87/Arg137/Asp85. The Y88A mutant protein was equally active against both dUTP and UTP, indicating that this conserved tyrosine residue is responsible for discrimination against ribonucleotides. The structure of DUT1 and site-directed mutagenesis support a role of the conserved Phe142 in the interaction with the uracil base. Our work provides further insight into the molecular mechanisms of substrate selectivity and catalysis of dUTPases.
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Abstract
Glucose is catabolized in yeast via two fundamental routes, glycolysis and the oxidative pentose phosphate pathway, which produces NADPH and the essential nucleotide component ribose-5-phosphate. Here, we describe riboneogenesis, a thermodynamically driven pathway that converts glycolytic intermediates into ribose-5-phosphate without production of NADPH. Riboneogenesis begins with synthesis, by the combined action of transketolase and aldolase, of the seven-carbon bisphosphorylated sugar sedoheptulose-1,7-bisphosphate. In the pathway's committed step, sedoheptulose bisphosphate is hydrolyzed to sedoheptulose-7-phosphate by the enzyme sedoheptulose-1,7-bisphosphatase (SHB17), whose activity we identified based on metabolomic analysis of the corresponding knockout strain. The crystal structure of Shb17 in complex with sedoheptulose-1,7-bisphosphate reveals that the substrate binds in the closed furan form in the active site. Sedoheptulose-7-phosphate is ultimately converted by known enzymes of the nonoxidative pentose phosphate pathway to ribose-5-phosphate. Flux through SHB17 increases when ribose demand is high relative to demand for NADPH, including during ribosome biogenesis in metabolically synchronized yeast cells.
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Proteomic analysis of excretory secretory products from Clonorchis sinensis adult worms: molecular characterization and serological reactivity of a excretory-secretory antigen-fructose-1,6-bisphosphatase. Parasitol Res 2011; 109:737-44. [PMID: 21424807 DOI: 10.1007/s00436-011-2316-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2010] [Accepted: 02/23/2011] [Indexed: 01/29/2023]
Abstract
Clonorchis sinensis is a food-borne zoonotic parasite that resides in bile ducts and causes clonorchiasis, which may result in cholelithiasis, cholecystitis, hepatic fibrosis, and liver tumors. Although total excretory secretory products (ESP) of C. sinensis adults induce hepatic fibrosis in vivo in rats, the causative mechanism is not well understood. To study components of the ESP, C. sinensis culture medium was collected and analyzed using shotgun LC-MS/MS. We identified a total of 110 proteins, including glycometabolic enzymes (such as fructose-1,6-bisphosphatase (FBPase) and enolase), detoxification enzymes (such as glutamate dehydrogenase, dihydrolipoamide dehydrogenase and cathepsin B endopeptidase), and a number of RAB family proteins. To identify a potential causative agent for hepatic fibrosis, we expressed and purified a recombinant FBPase, a 1,041-bp gene product that encodes a 41.7-kDa protein with prototypical FBPase domains and that can form a tetramer with a molecular mass of 166.8 kDa. In addition, we found that FBPase is an antigen present in the ESP and in circulation. Immunofluorescence showed that FBPase localizes to the intestinal cecum and vitellarium in C. sinensis adults. Our results describe the components of the excretory secretory products from C. sinensis adult worms and suggest that FBPase may be an important antigen present in the ESP of C. sinensis and may lay the foundation for additional studies on the development of clonorchiasis-associated hepatic fibrosis.
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21
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Current awareness on yeast. Yeast 2010. [DOI: 10.1002/yea.1724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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