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Identification, characterization and differential expression analysis of a pteridine synthesis related gene, Ccptps, in koi carp (Cyprinus carpio L.). Comp Biochem Physiol B Biochem Mol Biol 2022; 264:110814. [DOI: 10.1016/j.cbpb.2022.110814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 11/12/2022] [Accepted: 11/14/2022] [Indexed: 11/17/2022]
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2
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Zallot R, Harrison KJ, Kolaczkowski B, de Crécy-Lagard V. Functional Annotations of Paralogs: A Blessing and a Curse. Life (Basel) 2016; 6:life6030039. [PMID: 27618105 PMCID: PMC5041015 DOI: 10.3390/life6030039] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/29/2016] [Accepted: 09/02/2016] [Indexed: 12/15/2022] Open
Abstract
Gene duplication followed by mutation is a classic mechanism of neofunctionalization, producing gene families with functional diversity. In some cases, a single point mutation is sufficient to change the substrate specificity and/or the chemistry performed by an enzyme, making it difficult to accurately separate enzymes with identical functions from homologs with different functions. Because sequence similarity is often used as a basis for assigning functional annotations to genes, non-isofunctional gene families pose a great challenge for genome annotation pipelines. Here we describe how integrating evolutionary and functional information such as genome context, phylogeny, metabolic reconstruction and signature motifs may be required to correctly annotate multifunctional families. These integrative analyses can also lead to the discovery of novel gene functions, as hints from specific subgroups can guide the functional characterization of other members of the family. We demonstrate how careful manual curation processes using comparative genomics can disambiguate subgroups within large multifunctional families and discover their functions. We present the COG0720 protein family as a case study. We also discuss strategies to automate this process to improve the accuracy of genome functional annotation pipelines.
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Affiliation(s)
- Rémi Zallot
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA.
| | - Katherine J Harrison
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA.
| | - Bryan Kolaczkowski
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA.
| | - Valérie de Crécy-Lagard
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA.
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Phillips G, Grochowski LL, Bonnett S, Xu H, Bailly M, Haas-Blaby C, El Yacoubi B, Iwata-Reuyl D, White RH, de Crécy-Lagard V. Functional promiscuity of the COG0720 family. ACS Chem Biol 2012; 7:197-209. [PMID: 21999246 PMCID: PMC3262898 DOI: 10.1021/cb200329f] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The biosynthesis of GTP derived metabolites such as tetrahydrofolate (THF), biopterin (BH(4)), and the modified tRNA nucleosides queuosine (Q) and archaeosine (G(+)) relies on several enzymes of the Tunnel-fold superfamily. A subset of these proteins includes the 6-pyruvoyltetrahydropterin (PTPS-II), PTPS-III, and PTPS-I homologues, all members of the COG0720 family that have been previously shown to transform 7,8-dihydroneopterin triphosphate (H(2)NTP) into different products. PTPS-II catalyzes the formation of 6-pyruvoyltetrahydropterin in the BH(4) pathway, PTPS-III catalyzes the formation of 6-hydroxylmethyl-7,8-dihydropterin in the THF pathway, and PTPS-I catalyzes the formation of 6-carboxy-5,6,7,8-tetrahydropterin in the Q pathway. Genes of these three enzyme families are often misannotated as they are difficult to differentiate by sequence similarity alone. Using a combination of physical clustering, signature motif, phylogenetic codistribution analyses, in vivo complementation studies, and in vitro enzymatic assays, a complete reannotation of the COG0720 family was performed in prokaryotes. Notably, this work identified and experimentally validated dual function PTPS-I/III enzymes involved in both THF and Q biosynthesis. Both in vivo and in vitro analyses showed that the PTPS-I family could tolerate a translation of the active site cysteine and was inherently promiscuous, catalyzing different reactions on the same substrate or the same reaction on different substrates. Finally, the analysis and experimental validation of several archaeal COG0720 members confirmed the role of PTPS-I in archaeosine biosynthesis and resulted in the identification of PTPS-III enzymes with variant signature sequences in Sulfolobus species. This study reveals an expanded versatility of the COG0720 family members and illustrates that for certain protein families extensive comparative genomic analysis beyond homology is required to correctly predict function.
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Affiliation(s)
- Gabriela Phillips
- Department of Microbiology and Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611
| | - Laura L. Grochowski
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061
| | - Shilah Bonnett
- Department of Chemistry, Portland State University, Portland, OR 97207
| | - Huimin Xu
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061
| | - Marc Bailly
- Department of Microbiology and Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611
| | - Crysten Haas-Blaby
- Department of Microbiology and Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611
| | - Basma El Yacoubi
- Department of Microbiology and Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611
| | - Dirk Iwata-Reuyl
- Department of Chemistry, Portland State University, Portland, OR 97207
| | - Robert H. White
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061
| | - Valérie de Crécy-Lagard
- Department of Microbiology and Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611
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4
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Wang H, Yang B, Hao G, Feng Y, Chen H, Feng L, Zhao J, Zhang H, Chen YQ, Wang L, Chen W. Biochemical characterization of the tetrahydrobiopterin synthesis pathway in the oleaginous fungus Mortierella alpina. MICROBIOLOGY (READING, ENGLAND) 2011; 157:3059-3070. [PMID: 21852350 PMCID: PMC4811656 DOI: 10.1099/mic.0.051847-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Revised: 08/10/2011] [Accepted: 08/17/2011] [Indexed: 11/18/2022]
Abstract
We characterized the de novo biosynthetic pathway of tetrahydrobiopterin (BH₄) in the lipid-producing fungus Mortierella alpina. The BH₄ cofactor is essential for various cell processes, and is probably present in every cell or tissue of higher organisms. Genes encoding two copies of GTP cyclohydrolase I (GTPCH-1 and GTPCH-2) for the conversion of GTP to dihydroneopterin triphosphate (H₂-NTP), 6-pyruvoyltetrahydropterin synthase (PTPS) for the conversion of H₂-NTP to 6-pyruvoyltetrahydropterin (PPH₄), and sepiapterin reductase (SR) for the conversion of PPH₄ to BH₄, were expressed heterologously in Escherichia coli. The recombinant enzymes were produced as His-tagged fusion proteins and were purified to homogeneity to investigate their enzymic activities. Enzyme products were analysed by HPLC and electrospray ionization-MS. Kinetic parameters and other properties of GTPCH, PTPS and SR were investigated. Physiological roles of BH₄ in M. alpina are discussed, and comparative analyses between GTPCH, PTPS and SR proteins and other homologous proteins were performed. The presence of two functional GTPCH enzymes has, as far as we are aware, not been reported previously, reflecting the unique ability of this fungus to synthesize both BH₄ and folate, using the GTPCH product as a common substrate. To our knowledge, this study is the first to report the comprehensive characterization of a BH₄ biosynthesis pathway in a fungus.
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Affiliation(s)
- Hongchao Wang
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, PR China
| | - Bo Yang
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, PR China
| | - Guangfei Hao
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, PR China
| | - Yun Feng
- TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin Economic-Technological Development Area, Tianjin 300457, PR China
| | - Haiqin Chen
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, PR China
| | - Lu Feng
- TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin Economic-Technological Development Area, Tianjin 300457, PR China
| | - Jianxin Zhao
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, PR China
| | - Hao Zhang
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, PR China
| | - Yong Q. Chen
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, PR China
| | - Lei Wang
- TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin Economic-Technological Development Area, Tianjin 300457, PR China
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi 214122, PR China
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5
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Sumi-Ichinose C, Urano F, Shimomura A, Sato T, Ikemoto K, Shiraishi H, Senda T, Ichinose H, Nomura T. Genetically rescued tetrahydrobiopterin-depleted mice survive with hyperphenylalaninemia and region-specific monoaminergic abnormalities. J Neurochem 2005; 95:703-14. [PMID: 16135092 DOI: 10.1111/j.1471-4159.2005.03402.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
One of the possibly mutated genes in DOPA-responsive dystonia (DRD, Segawa's disease) is the gene encoding GTP cyclohydrolase I, which is the rate-limiting enzyme for tetrahydrobiopterin (BH4) biosynthesis. Based on our findings on 6-pyruvoyltetrahydropterin synthase (PTS) gene-disrupted (Pts(-/-)) mice, we suggested that the amount of tyrosine hydroxylase (TH) protein in dopaminergic nerve terminals is regulated by the intracellular concentration of BH4. In this present work, we rescued Pts(-/-) mice by transgenic introduction of human PTS cDNA under the control of the dopamine beta-hydroxylase promoter to examine regional differences in the sensitivity of dopaminergic neurons to BH4-insufficiency. The DPS-rescued (Pts(-/-), DPS) mice showed severe hyperphenylalaninemia. Human PTS was efficiently expressed in noradrenergic regions but only in a small number of dopaminergic neurons. Biopterin and dopamine contents, and TH activity in the striatum were poorly restored compared with those in the midbrain. TH-immunoreactivity in the lateral region of the striatum was far weaker than that in the medial region or in the nucleus accumbens. We concluded that dopaminergic nerve terminals projecting to the lateral region of the striatum are the most sensitive to BH4-insufficiency. Biochemical and pathological changes in DPS-rescued mice were similar to those in human malignant hyperphenylalaninemia and DRD.
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Affiliation(s)
- Chiho Sumi-Ichinose
- Department of Pharmacology, School of Medicine, Fujita Health University, Tokoake, Aichi, Japan.
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6
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Suzuki T, Kurita H, Ichinose H. GTP cyclohydrolase I utilizes metal-free GTP as its substrate. EUROPEAN JOURNAL OF BIOCHEMISTRY 2004; 271:349-55. [PMID: 14717702 DOI: 10.1046/j.1432-1033.2003.03933.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
GTP cyclohydrolase I (GCH) is the rate-limiting enzyme for the synthesis of tetrahydrobiopterin and its activity is important in the regulation of monoamine neurotransmitters such as dopamine, norepinephrine and serotonin. We have studied the action of divalent cations on the enzyme activity of purified recombinant human GCH expressed in Escherichia coli. First, we showed that the enzyme activity is dependent on the concentration of Mg-free GTP. Inhibition of the enzyme activity by Mg2+, as well as by Mn2+, Co2+ or Zn2+, was due to the reduction of the availability of metal-free GTP substrate for the enzyme, when a divalent cation was present at a relatively high concentration with respect to GTP. We next examined the requirement of Zn2+ for enzyme activity by the use of a protein refolding assay, because the recombinant enzyme contained approximately one zinc atom per subunit of the decameric protein. Only when Zn2+ was present was the activity of the denatured enzyme effectively recovered by incubation with a chaperone protein. These are the first data demonstrating that GCH recognizes Mg-free GTP and requires Zn2+ for its catalytic activity. We suggest that the cellular concentration of divalent cations can modulate GCH activity, and thus tetrahydrobiopterin biosynthesis as well.
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Affiliation(s)
- Takahiro Suzuki
- Department of Life Science, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Japan
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7
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Woo HJ, Hwang YK, Kim YJ, Kang JY, Choi YK, Kim CG, Park YS. Escherichia coli 6-pyruvoyltetrahydropterin synthase ortholog encoded by ygcM has a new catalytic activity for conversion of sepiapterin to 7,8-dihydropterin. FEBS Lett 2002; 523:234-8. [PMID: 12123838 DOI: 10.1016/s0014-5793(02)02997-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The putative gene (ygcM) of Escherichia coli was verified in vitro to encode the ortholog of 6-pyruvoyltetrahydropterin synthase (PTPS). Unexpectedly, the enzyme was found to convert sepiapterin to 7,8-dihydropterin without any cofactors. The enzymatic product 7,8-dihydropterin was identified by HPLC and mass spectrometry analyses, suggesting a novel activity of the enzyme to cleave the C6 side chain of sepiapterin. The optimal activity occurred at pH 6.5-7.0. The reaction rate increased up to 3.2-fold at 60-80 degrees C, reflecting the thermal stability of the enzyme. The reaction required no metal ion and was activated slightly by low concentrations (1-5 mM) of EDTA. The apparent K(m) value for sepiapterin was determined as 0.92 mM and the V(max) value was 151.3 nmol/min/mg. The new catalytic function of E. coli PTPS does not imply any physiological role, because sepiapterin is not an endogenous substrate of the organism. The same activity, however, was also detected in a PTPS ortholog of Synechocystis sp. PCC 6803 but not significant in Drosophila and human enzymes, suggesting that the activity may be prevalent in bacterial PTPS orthologs.
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Affiliation(s)
- Hyun Joo Woo
- Department of Microbiology, Inje University, 621-749, Kimhae, South Korea
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8
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Sumi-Ichinose C, Ohtsuki M, Shiraishi H, Nomura T. [Perspectives on tetrahydrobiopterin research]. Nihon Yakurigaku Zasshi 2001; 118:371-7. [PMID: 11778454 DOI: 10.1254/fpj.118.371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Tetrahydrobiopterin ((6R)-L-erythro-tetrahydrobiopterin, BH4) is de novo synthesized from GTP. Enzymes involved in its synthesis are the rate limiting enzyme GTP cyclohydrolase I, 6-pyruvoyl tetrahydropterin synthase (PTPS) and sepiapterin reductase. Abnormalities in the metabolism of BH4 have been demonstrated in some diseases affecting the central nervous systems such as atypical phenylketonuria, hereditary progressive dystonia (Segawa's disease). Furthermore, BH4 has been shown to be involved in vascular protection. It is suggested that the dysfunction of endothelial BH4 leads to atherosclerosis. Recently we established BH4-deficient mice by disrupting the PTPS gene to investigate the effects of BH4 depletion on the animals and the involvement of BH4 in regulating biological functions including neural systems. Investigation utilizing this model animal can contribute to the development of new therapeutic strategies toward various diseases involving neurological and vascular systems. Pterin derivatives other than biopterin may also be involved in the regulation of a variety of biological functions. We found that ciliated protozoan Tetrahymena pyriformis synthesizes tetrahydromonapterin, isomer of BH4, and its levels alter according to the progress of the cell cycle. How pterin derivatives are related to the human physiology and diseases is an interesting subject of investigation.
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Affiliation(s)
- C Sumi-Ichinose
- Department of Pharmacology, Fujita Health University School of Medicine, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192, Japan
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9
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Kawai K, Fujimoto K, Okamoto A, Inaba A, Yamada H, Katoh S. Transient Activation of Dihydropteridine Reductase by Ca 2+-activated Proteolysis. Zoolog Sci 2000. [DOI: 10.2108/0289-0003(2000)17[437:taodrb]2.0.co;2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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10
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Ploom T, Thöny B, Yim J, Lee S, Nar H, Leimbacher W, Richardson J, Huber R, Auerbach G. Crystallographic and kinetic investigations on the mechanism of 6-pyruvoyl tetrahydropterin synthase. J Mol Biol 1999; 286:851-60. [PMID: 10024455 DOI: 10.1006/jmbi.1998.2511] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The enzyme 6-pyruvoyl tetrahydropterin synthase (PTPS) catalyses the second step in the de novo biosynthesis of tetrahydrobiopterin, the conversion of dihydroneopterin triphosphate to 6-pyruvoyl tetrahydropterin. The Zn and Mg-dependent reaction includes a triphosphate elimination, a stereospecific reduction of the N5-C6 double bond and the oxidation of both side-chain hydroxyl groups. The crystal structure of the inactive mutant Cys42Ala of PTPS in complex with its natural substrate dihydroneopterinetriphosphate was determined at 1.9 A resolution. Additionally, the uncomplexed enzyme was refined to 2.0 A resolution. The active site of PTPS consists of the pterin-anchoring Glu A107 neighboured by two catalytic motifs: a Zn(II) binding site and an intersubunit catalytic triad formed by Cys A42, Asp B88 and His B89. In the free enzyme the Zn(II) is in tetravalent co-ordination with three histidine ligands and a water molecule. In the complex the water is replaced by the two substrate side-chain hydroxyl groups yielding a penta-co-ordinated Zn(II) ion. The Zn(II) ion plays a crucial role in catalysis. It activates the protons of the substrate, stabilizes the intermediates and disfavours the breaking of the C1'C2' bond in the pyruvoyl side-chain. Cys A42 is activated by His B89 and Asp B88 for proton abstraction from the two different substrate side-chain atoms C1', and C2'. Replacing Ala A42 in the mutant structure by the wild-type Cys by modelling shows that the C1' and C2' substrate side-chain protons are at equal distances to Cys A42 Sgamma. The basicity of Cys A42 may be increased by a catalytic triad His B89 and Asp B88. The active site of PTPS seems to be optimised to carry out proton abstractions from two different side-chain C1' and C2' atoms, with no obvious preference for one of them. Kinetic studies with dihydroneopterin monophosphate reveal that the triphosphate moiety of the substrate is necessary for enzyme specifity.
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Affiliation(s)
- T Ploom
- Max-Planck-Institut für Biochemie, Abteilung Strukturforschung, Am Klopferspitz 18a, Martinsried, 82152, Germany.
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11
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Turri MO, Ilg EC, Thöny B, Blau N. Structure, genomic localization and recombinant expression of the mouse 6-pyruvoyl-tetrahydropterin synthase gene. Biol Chem 1998; 379:1441-7. [PMID: 9894812 DOI: 10.1515/bchm.1998.379.12.1441] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The 6-pyruvoyl-tetrahydropterin synthase (PTPS) is the second enzyme in the biosynthetic pathway from GTP to tetrahydrobiopterin (BH4). BH4 is an essential cofactor of NO synthases and aromatic amino acid hydroxylases, the latter being responsible for hepatic phenylalanine degradation and monoamine neurotransmitter biosynthesis. BH4 deficiency due to autosomal recessive mutations in the human gene for PTPS leads to a broad range of phenotypes ranging from mild hyperphenylalaninemia to high phenylalanine levels concomitant with neurotransmitter depletion. An animal model to study PTPS deficiency is thus desired to investigate the molecular basis of the disease and its variability. Here, we report on the isolation and recombinant expression of the mouse PTPS gene, Pts. It is located on chromosome 9C-D and contains six exons with an open reading frame of 144 codons. The derived protein monomer has a molecular mass of 16187 Da and shows 82% and 93% identity to its human and rat counterparts, respectively. The mouse PTPS was expressed in bacterial cells and purified to homogeneity. The kinetic properties of the recombinant protein, apparent Km of approximately 10 microM and k(cat) of 0.27 s(-1), were similar to the native mouse enzyme in liver and brain extracts, and to the corresponding human and rat PTPS.
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Affiliation(s)
- M O Turri
- Department of Pediatrics, University of Zürich, Switzerland
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12
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Imaoka T, Date I, Ohmoto T, Nagatsu T. Significant behavioral recovery in Parkinson's disease model by direct intracerebral gene transfer using continuous injection of a plasmid DNA-liposome complex. Hum Gene Ther 1998; 9:1093-102. [PMID: 9607420 DOI: 10.1089/hum.1998.9.7-1093] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
As an alternative to virus-mediated gene transfer, we previously demonstrated a simple, safe, and efficient transfer of foreign gene into the central nervous system using continuous injection of a plasmid DNA-cationic liposome complex. To explore whether this approach can be applied to the treatment of certain neurological disorders, we used an experimental model of Parkinson's disease (PD) in the present study. Following continuous injection for 7 days, tyrosine hydroxylase (TH) and aromatic L-amino acid decarboxylase (AADC) genes carried by a bovine papilloma virus-based plasmid vector were efficiently introduced into glial cells in the striatum of 6-hydroxydopamine-lesioned rats. Significant recovery in apomorphine-induced rotational behavior of PD models was obtained by transfection of TH gene and this effect continued for up to 5 weeks after injection. Moreover, cotransfection of TH with AADC genes was readily accomplished by this procedure and resulted in a greater and longer-lasting improvement of apomorphine-induced rotational behavior than was achieved by transfection of TH gene alone. We suggest that this approach is a controllable and manageable alternative to other methods of gene therapy for the treatment of PD.
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Affiliation(s)
- T Imaoka
- Department of Neurological Surgery, Okayama University Medical School, Japan
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13
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Hoshiga M, Hatakeyama K. Enzymatic synthesis of 6R-[U-14C]tetrahydrobiopterin from [U-14C]GTP. Methods Enzymol 1997; 281:123-9. [PMID: 9250975 DOI: 10.1016/s0076-6879(97)81017-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- M Hoshiga
- Osaka Medical College, Department of Internal Medicine, Japan
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14
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Werner ER, Werner-Felmayer G, Wachter H. High-performance liquid chromatographic methods for the quantification of tetrahydrobiopterin biosynthetic enzymes. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1996; 684:51-8. [PMID: 8906465 DOI: 10.1016/0378-4347(95)00507-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Tetrahydrobiopterin is a cofactor in hydroxylation reactions, including phenylalanine 4-monooxygenase, tyrosine 3-monooxygenase, tryptophan 5-monooxygenase, alkyl glycol ether monooxygenase and nitric oxide synthase. Determination of its biosynthesis is carried out to diagnose inherited diseases leading to partial defects in tetrahydrobiopterin synthesis. In addition, tetrahydrobiopterin synthesis is induced by proinflammatory cytokines, and intracellular levels of tetrahydro-biopterin in many cases limit the activity of tetrahydrobiopterin-dependent reactions, such as nitric oxide synthase in intact cells. Biosynthesis of tetrahydrobiopterin from guanosine 5'-triphosphate (GTP) requires the action of three enzymes, GTP-cyclohydrolase I (E.C. 3.5.4.16), 6-pyruvoyl tetrahydropterin synthase (EC, 4.6.1.10) and sepiapterin reductase (E.C. 1.1.1.153). Methods for quantification of biopterin and related pteridines in biological matrices by HPLC and application of these for determining the activity of the three tetrahydrobiopterin biosynthetic enzymes are reviewed in this article.
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Affiliation(s)
- E R Werner
- Institut für Medizinische Chemie and Piechemic, Universität Innsbuck, Austria
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15
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Werner ER, Werner-Felmayer G, Wachter H, Mayer B. Biosynthesis of nitric oxide: dependence on pteridine metabolism. Rev Physiol Biochem Pharmacol 1996; 127:97-135. [PMID: 8533013 DOI: 10.1007/bfb0048266] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- E R Werner
- Institut für Medizinische Chemie und Biochemie, Universität Innsbruck, Austria
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16
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Oppliger T, Thöny B, Nar H, Bürgisser D, Huber R, Heizmann CW, Blau N. Structural and functional consequences of mutations in 6-pyruvoyltetrahydropterin synthase causing hyperphenylalaninemia in humans. Phosphorylation is a requirement for in vivo activity. J Biol Chem 1995; 270:29498-506. [PMID: 7493990 DOI: 10.1074/jbc.270.49.29498] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Four naturally occurring mutants with single amino acid alterations in human 6-pyruvoyltetrahydropterin synthase (PTPS) were overexpressed and characterized in vitro. The corresponding DNA mutations were found in patients with hyperphenylalaninemia and monoamine neurotransmitter insufficiency due to lack of the tetrahydrobiopterin biosynthetic enzyme PTPS. To predict the structure of the mutant enzymes, computer modeling was performed based on the solved three-dimensional structure of the homohexameric rat enzyme. One mutant (delta V57) is incorrectly folded and thus unstable in vitro and in vivo, while a second mutant (P87L) has substantial activity but enhanced sensitivity to local unfolding. Two other mutants, R16C and R25Q, form stable homomultimers and exhibit significant activity in vitro but no activity in COS-1 cells. In vivo 32P labeling showed that wild-type PTPS, P87L, and R25Q are phosphorylated, while R16C is not modified. This strongly suggests that the serine 19 within the consensus sequence for various kinases, RXXS, is the site of modification. Our results demonstrate that PTPS undergoes protein phosphorylation and requires additional, not yet identified post-translational modification(s) for its in vivo function.
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Affiliation(s)
- T Oppliger
- Department of Pediatrics, University of Zürich, Switzerland
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Regulation of tetrahydrobiopterin biosynthesis in cultured dopamine neurons by depolarization and cAMP. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)32647-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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18
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Bürgisser DM, Thöny B, Redweik U, Hunziker P, Heizmann CW, Blau N. Expression and characterization of recombinant human and rat liver 6-pyruvoyl tetrahydropterin synthase. Modified cysteine residues inhibit the enzyme activity. EUROPEAN JOURNAL OF BIOCHEMISTRY 1994; 219:497-502. [PMID: 8307017 DOI: 10.1111/j.1432-1033.1994.tb19964.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
6-Pyruvoyl-tetrahydropterin synthase is the rate-limiting enzyme in the synthesis of human tetrahydrobiopterin, a cofactor for several hydroxylases involved in catecholamine and serotonin biosynthesis. The human and rat liver cDNAs encoding the 16-kDa subunit of 6-pyruvoyl tetrahydropterin synthase were expressed as maltose-binding-6-pyruvoyl-tetrahydropterin-synthase fusion proteins. After cleavage from the fusion protein, the human and rat enzymes were purified to homogeneity. Apparent Km for the substrate dihydroneopterin triphosphate (8.5 microM for the human and 8.0 microM for the rat enzyme), pI (4.6 and 4.8) and heat stability of the recombinant enzymes were similar to the native enzymes. The specific activity of the enzymes was enhanced up to fourfold in the presence of dithiothreitol during purification. The modification of the only cysteine residue in rat 6-pyruvoyl tetrahydropterin synthase, which is conserved in the human enzyme, inhibited its activity up to 80%. Modification under non-reducing conditions of both cysteine residues of the human enzyme by N-ethylpyridine resulted in a 95% loss of enzyme activity. This demonstrates that the two cysteines are not linked by disulfide bridges but rather involved in catalysis. Cross-linking experiments and analysis by gel electrophoresis showed predominantly trimeric and hexameric forms of the recombinant enzymes from both species suggesting that the native form is a homohexamer of 98 kDa, for the human, and 95 kDa, for the rat enzyme, composed of two trimeric subunits.
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Affiliation(s)
- D M Bürgisser
- Department of Pediatrics, University of Zürich, Switzerland
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19
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Hirayama K, Lentz SI, Kapatos G. Tetrahydrobiopterin cofactor biosynthesis: GTP cyclohydrolase I mRNA expression in rat brain and superior cervical ganglia. J Neurochem 1993; 61:1006-14. [PMID: 8103077 DOI: 10.1111/j.1471-4159.1993.tb03614.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
GTP cyclohydrolase I (GTPCH) is the rate-limiting enzyme in the biosynthesis of tetrahydrobiopterin, the reduced pteridine cofactor required for catecholamine (CA), indoleamine, and nitric oxide biosynthesis. We have used the reverse transcription-polymerase chain reaction technique, based on the published cDNA sequence for rat liver GTPCH, to clone a portion of the GTPCH transcript from rat adrenal gland mRNA and have used this clone for the analysis of GTPCH mRNA in brain and other tissues of the rat by northern blot, nuclease protection assay, and in situ hybridization. Two GTPCH mRNA transcripts of 1.2 and 3.8 kb in length were detected by northern blot, with the 1.2-kb form predominating in the liver and the 3.8-kb form in the pineal gland, adrenal gland, brainstem, and hypothalamic neurons maintained in culture. In situ hybridization studies localized GTPCH mRNA to CA-containing perikarya in the locus ceruleus, ventral tegmental area, and substantia nigra, pars compacta. Levels of GTPCH mRNA in central and peripheral catecholamine neurons determined by nuclease protection assay were increased twofold 24 h after a single injection of the CA-depleting drug reserpine; both the 1.2- and 3.8-kb transcripts were increased in the adrenal gland. Low levels of GTPCH mRNA were also detected by nuclease protection assay in the striatum, hippocampus, and cerebellum, brain regions that do not contain monoaminergic perikarya.
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Affiliation(s)
- K Hirayama
- Department of Psychiatry, Wayne State University School of Medicine, Detroit, Michigan 48201
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20
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Thöny B, Leimbacher W, Blau N, Heizmann CW, Bürgisser D. Human liver 6-pyruvoyl-tetrahydropterin synthase: expression of the cDNA, purification and preliminary characterization of the recombinant protein. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1993; 338:187-90. [PMID: 8304107 DOI: 10.1007/978-1-4615-2960-6_37] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- B Thöny
- Division of Clinical Chemistry, University Children's Hospital, Zürich, Switzerland
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21
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Masada M. Enzymatic properties of 6-pyruvoyl tetrahydropterin synthase purified from fat bodies of silkworm larvae. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1993; 338:191-4. [PMID: 8304108 DOI: 10.1007/978-1-4615-2960-6_38] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- M Masada
- Department of Bioresources Chemistry, Faculty of Horticulture, Chiba University, Japan
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22
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Levine RA, States JC, Anastasiadis PZ, Kuhn DM. Cloning and characterization of genes encoding tetrahydrobiopterin biosynthetic enzymes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1993; 338:139-45. [PMID: 7905695 DOI: 10.1007/978-1-4615-2960-6_28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- R A Levine
- William T. Gossett Neurology Laboratories, Henry Ford Hospital, Detroit, MI 48201
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23
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Hoshiga M, Hatakeyama K, Kagamiyama H. Tissue distribution of tetrahydrobiopterin generating enzymes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1993; 338:223-6. [PMID: 8304114 DOI: 10.1007/978-1-4615-2960-6_44] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- M Hoshiga
- Department of Medical Chemistry, Osaka Medical College, Japan
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24
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Hirayama K, Lentz SI, Kapatos G. Expression of GTP cyclohydrolase I (GTPCH) mRNA in the rat: tissue distribution and effect of reserpine. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1993; 338:175-8. [PMID: 8304104 DOI: 10.1007/978-1-4615-2960-6_34] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- K Hirayama
- Department of Psychiatry, Wayne State University School of Medicine, Detroit, Michigan 48201
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25
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Thöny B, Leimbacher W, Bürgisser D, Heizmann CW. Human 6-pyruvoyltetrahydropterin synthase: cDNA cloning and heterologous expression of the recombinant enzyme. Biochem Biophys Res Commun 1992; 189:1437-43. [PMID: 1282802 DOI: 10.1016/0006-291x(92)90235-d] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
6-Pyruvoyl-tetrahydropterin synthase (PTPS) is involved in the biosynthesis of tetrahydrobiopterin (BH4), an essential cofactor for enzymes such as the hepatic phenylalanine hydroxylase. BH4 deficiency causes malignant hyperphenylalaninemia. We cloned the human liver cDNA encoding PTPS. The coding region for PTPS contains 145 amino acids and predicts a polypeptide of 16'387 Da. The human amino acid sequence showed a 82% identity with the rat liver sequence. Expression of the cDNA in E. coli yielded the active enzyme and showed immunoreactivity with antibodies against the rat liver PTPS. This is the basis for the molecular understanding of BH4 deficiency in patients suffering from a defect in PTPS activity.
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Affiliation(s)
- B Thöny
- Department of Pediatrics, University of Zürich, Switzerland
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26
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Hatakeyama K, Harada T, Kagamiyama H. IMP dehydrogenase inhibitors reduce intracellular tetrahydrobiopterin levels through reduction of intracellular GTP levels. Indications of the regulation of GTP cyclohydrolase I activity by restriction of GTP availability in the cells. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(19)36747-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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27
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Hauer CR, Leimbacher W, Hunziker P, Neuheiser F, Blau N, Heizmann CW. 6-pyruvoyl tetrahydropterin synthase from salmon liver: amino acid sequence analysis by tandem mass spectrometry. Biochem Biophys Res Commun 1992; 182:953-9. [PMID: 1734893 DOI: 10.1016/0006-291x(92)91824-a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The most frequent variant of atypical phenylketonuria, an inborn error of metabolism, is characterized by a low activity of the 6-pyruvoyl tetrahydropterin synthase. We purified and characterized this enzyme from salmon liver known to contain high levels. After digestion, peptides were sequenced by tandem mass spectrometry and/or automated Edman microsequence analysis. Both a free amine terminus and an N-acetylated amine terminus were found, indicating the presence of two isoforms. The peptide sequences determined here have a high degree of homology with the protein sequence deduced from cDNA for rat 6-pyruvoyl tetrahydropterin synthase (1), however, the amine termini of these proteins differ significantly.
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Affiliation(s)
- C R Hauer
- Department of Pediatrics, University of Zurich, Switzerland
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