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International Journal of Molecular... May 2023Autotaxin (ATX) or Ectonucleotide Pyrophosphatase/Phosphodiesterase 2 (ENPP2) is a secreted enzyme with lysophospholipase D activity, with its primary function being the...
Autotaxin (ATX) or Ectonucleotide Pyrophosphatase/Phosphodiesterase 2 (ENPP2) is a secreted enzyme with lysophospholipase D activity, with its primary function being the extracellular hydrolysis of lysophosphatidylcholine (LPC) to lysophosphatidic acid (LPA), a bioactive lipid [...].
Topics: Humans; Phosphoric Diester Hydrolases; Neoplasms; Lysophospholipids; Embryonic Development
PubMed: 37176032
DOI: 10.3390/ijms24098325 -
Bone Dec 2021Awareness for hypophosphatemic rickets has increased in the last years, based on the availability of specific medical treatments. Autosomal recessive hypophosphatemic... (Review)
Review
Awareness for hypophosphatemic rickets has increased in the last years, based on the availability of specific medical treatments. Autosomal recessive hypophosphatemic rickets type 2 (ARHR2) is a rare form of hypophosphatemic rickets, which is known to develop in survivors of generalized arterial calcification of infancy (GACI). Both disorders are based on a deficiency of ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) and present with a high clinical variability and a lack of a phenotype-genotype association. ARHR2 is characterized by phosphate wasting due to elevated fibroblast growth factor 23 (FGF23) levels and might represent a response of the organism to minimize ectopic calcification in individuals with ENPP1-deficiency. This report reviews the recent clinical and preclinical data on this ultra-rare disease in childhood.
Topics: Familial Hypophosphatemic Rickets; Fibroblast Growth Factor-23; Fibroblast Growth Factors; Humans; Phosphates; Phosphoric Diester Hydrolases; Pyrophosphatases; Rickets, Hypophosphatemic
PubMed: 34252603
DOI: 10.1016/j.bone.2021.116111 -
Cell Cycle (Georgetown, Tex.) Jul 2020Hepatocellular carcinoma (HCC) has a poor prognosis, owing to its high potential for growth and metastasis. In this study, we aimed to investigate the roles of in human...
Hepatocellular carcinoma (HCC) has a poor prognosis, owing to its high potential for growth and metastasis. In this study, we aimed to investigate the roles of in human HCCcell growth and metastasis. We analyzed the expression level in human HCC tissues paired normal tissues in the Oncomine database, and assessed the relationship between the expression levels with HCC patient's overall survival and the prognostic value of in human HCC by Kaplan-Meier survival analysis. Real-time PCR and Western Blot were used to examine the expression levels of in normal liver cell line (LO2) and human HCC cell lines (SMCC-7721, HepG2, Huh7, MHCC-97 H, and LM3). Through lentivirus infection, we established human HCC stable cell lines (Huh7 and LM3) overexpressing . Then, we detected these cell viability, colony , and invasion. Subsequently, we performed the gene set enrichment analysis (GSEA) for the RNA-seq data of HCC patients from TCGA. Finally, we examined the expression level of several oncogenes, including CCNB1, PKM2, MMP7, and MMP9, in these cells via real-time PCR assay. Here, we found thatis significantly downregulated in the human HCC tissues paired normal tissues. Furthermore, the high expression level of is associated with better clinical outcomes in human HCC. Overexpression of inhibitscell growth and metastasis in human HCC cells, and expression levels negatively correlate with cell cycle and metastasis in HCC tissues. Moreover, the level of is negatively correlated with CCNB1, PKM2, MMP7, and MMP9 in human HCC cells and HCC tissues. These findings highlight a novel tumor suppressor in human HCC growth and metastasis, and provide a promising diagnostic and prognostic factor for humanHCC.
Topics: Carcinoma, Hepatocellular; Cell Cycle; Cell Movement; Cell Proliferation; Cell Survival; Gene Expression Regulation, Neoplastic; Humans; Inorganic Pyrophosphatase; Liver Neoplasms; Neoplasm Invasiveness; Neoplasm Metastasis; Neoplasm Proteins; Treatment Outcome; Tumor Stem Cell Assay
PubMed: 32578511
DOI: 10.1080/15384101.2020.1783472 -
Molecular Plant Pathology Mar 2021Plant viruses typically have highly condensed genomes, yet the plant-pathogenic viruses Cassava brown streak virus, Ugandan cassava brown streak virus, and Euphorbia... (Review)
Review
Plant viruses typically have highly condensed genomes, yet the plant-pathogenic viruses Cassava brown streak virus, Ugandan cassava brown streak virus, and Euphorbia ringspot virus are unusual in encoding an enzyme not yet found in any other virus, the "house-cleaning" enzyme inosine triphosphatase. Inosine triphosphatases (ITPases) are highly conserved enzymes that occur in all kingdoms of life and perform a house-cleaning function by hydrolysing the noncanonical nucleotide inosine triphosphate to inosine monophosphate. The ITPases encoded by cassava brown streak virus and Ugandan cassava brown streak virus have been characterized biochemically and are shown to have typical ITPase activity. However, their biological role in virus infection has yet to be elucidated. Here we review what is known of viral-encoded ITPases and speculate on potential roles in infection with the aim of generating a greater understanding of cassava brown streak viruses, a group of the world's most devastating viruses.
Topics: Manihot; Plant Diseases; Potyviridae; Pyrophosphatases; Viral Proteins; Inosine Triphosphatase
PubMed: 33471956
DOI: 10.1111/mpp.13021 -
Frontiers in Oncology 2022Inorganic pyrophosphatase (PPA1) encoded by PPA1 gene belongs to Soluble Pyrophosphatases (PPase) family and is expressed widely in various tissues of Homo sapiens, as... (Review)
Review
Inorganic pyrophosphatase (PPA1) encoded by PPA1 gene belongs to Soluble Pyrophosphatases (PPase) family and is expressed widely in various tissues of Homo sapiens, as well as significantly in a variety of malignancies. The hydrolysis of inorganic pyrophosphate (PPi) to produce orthophosphate (Pi) not only dissipates the negative effects of PPi accumulation, but the energy released by this process also serves as a substitute for ATP. PPA1 is highly expressed in a variety of tumors and is involved in proliferation, invasion, and metastasis during tumor development, through the JNK/p53, Wnt/β-catenin, and PI3K/AKT/GSK-3β signaling pathways. Because of its remarkable role in tumor development, PPA1 may serve as a biological target for adjuvant therapy of tumor malignancies. Further, PPA1 is a potential biomarker to predict survival in patients with cancer, where the assessment of its transcriptional regulation can provide an in-depth understanding. Herein, we describe the signaling pathways through which PPA1 regulates malignant tumor progression and provide new insights to establish PPA1 as a biomarker for tumor diagnosis.
PubMed: 36505776
DOI: 10.3389/fonc.2022.1012090 -
ChemMedChem Nov 2021Inhibition of membrane-bound pyrophosphatase (mPPase) with small molecules offer a new approach in the fight against pathogenic protozoan parasites. mPPases are absent...
Inhibition of membrane-bound pyrophosphatase (mPPase) with small molecules offer a new approach in the fight against pathogenic protozoan parasites. mPPases are absent in humans, but essential for many protists as they couple pyrophosphate hydrolysis to the active transport of protons or sodium ions across acidocalcisomal membranes. So far, only few nonphosphorus inhibitors have been reported. Here, we explore the chemical space around previous hits using a combination of screening and synthetic medicinal chemistry, identifying compounds with low micromolar inhibitory activities in the Thermotoga maritima mPPase test system. We furthermore provide early structure-activity relationships around a new scaffold having a pyrazolo[1,5-a]pyrimidine core. The most promising pyrazolo[1,5-a]pyrimidine congener was further investigated and found to inhibit Plasmodium falciparum mPPase in membranes as well as the growth of P. falciparum in an ex vivo survival assay.
Topics: Dose-Response Relationship, Drug; Humans; Molecular Structure; Pyrazoles; Pyrimidines; Pyrophosphatases; Structure-Activity Relationship
PubMed: 34459148
DOI: 10.1002/cmdc.202100392 -
Experimental Dermatology Apr 2022Pseudoxanthoma elasticum (PXE; OMIM 264800) is a rare heritable multisystem disorder, characterized by ectopic mineralization affecting elastic fibres in the skin, eyes...
Pseudoxanthoma elasticum (PXE; OMIM 264800) is a rare heritable multisystem disorder, characterized by ectopic mineralization affecting elastic fibres in the skin, eyes and the cardiovascular system. Skin findings often lead to early diagnosis of PXE, but currently, no specific treatment exists to counteract the progression of symptoms. PXE belongs to a group of Mendelian calcification disorders linked to pyrophosphate metabolism, which also includes generalized arterial calcification of infancy (GACI) and arterial calcification due to CD73 deficiency (ACDC). Inactivating mutations in ABCC6, ENPP1 and NT5E are the genetic cause of these diseases, respectively, and all of them result in reduced inorganic pyrophosphate (PP ) concentration in the circulation. Although PP is a strong inhibitor of ectopic calcification, oral supplementation therapy was initially not considered because of its low bioavailability. Our earlier work however demonstrated that orally administered pyrophosphate inhibits ectopic calcification in the animal models of PXE and GACI, and that orally given Na P O is absorbed in humans. Here, we report that gelatin-encapsulated Na H P O has similar absorption properties in healthy volunteers and people affected by PXE. The sodium-free K H P O form resulted in similar uptake in healthy volunteers and inhibited calcification in Abcc6 mice as effectively as its sodium counterpart. Novel pyrophosphate compounds showing higher bioavailability in mice were also identified. Our results provide an important step towards testing oral PP in clinical trials in PXE, or potentially any condition accompanied by ectopic calcification including diabetes, chronic kidney disease or ageing.
Topics: Animals; Dietary Supplements; Diphosphates; Humans; Mice; Mutation; Phosphoric Diester Hydrolases; Pseudoxanthoma Elasticum; Pyrophosphatases; Vascular Calcification
PubMed: 34758173
DOI: 10.1111/exd.14498 -
MBio Dec 2022Expression of the fission yeast Schizosaccharomyces pombe phosphate regulon is sensitive to the intracellular level of the inositol pyrophosphate signaling molecule...
Expression of the fission yeast Schizosaccharomyces pombe phosphate regulon is sensitive to the intracellular level of the inositol pyrophosphate signaling molecule 1,5-IP. IP dynamics are determined by Asp1, a bifunctional enzyme consisting of an N-terminal kinase domain and a C-terminal pyrophosphatase domain that catalyze IP synthesis and catabolism, respectively. Here, we report structures of the Asp1 kinase domain, crystallized with two protomers in the asymmetric unit, one of which was complexed with ligands (ADPNP, ADP, or ATP; Mg or Mn; IP, 5-IP, or 1,5-IP) and the other which was ligand-free. The ligand-free enzyme adopts an "open" conformation that allows ingress of substrates and egress of products. ADPNP, ADP, and ATP and associated metal ions occupy a deep phospho-donor pocket in the active site. IP or 5-IP engagement above the nucleotide favors adoption of a "closed" conformation, in which surface protein segments undergo movement and a disordered-to-ordered transition to form an inositol polyphosphate-binding site. In a structure mimetic of the kinase Michaelis complex, the anionic 5-IP phosphates are encaged by an ensemble of nine cationic amino acids: Lys43, Arg223, Lys224, Lys260, Arg274, Arg285, Lys290, Arg293, and Lys341. Alanine mutagenesis of amino acids that contact the adenosine nucleoside of the ATP donor underscored the contributions of Asp258 interaction with the ribose 3'-OH and of Glu248 with adenine-. Changing Glu248 to Gln elicited a gain of function whereby the kinase became adept at using GTP as phosphate donor. Wild-type Asp1 kinase can utilize -benzyl-ATP as phosphate donor. The inositol pyrophosphate signaling molecule 1,5-IP modulates fission yeast phosphate homeostasis via its action as an agonist of RNA 3'-processing and transcription termination. Cellular IP levels are determined by Asp1, a bifunctional enzyme composed of an N-terminal kinase and a C-terminal pyrophosphatase domain. Here, we present a series of crystal structures of the Asp1 kinase domain, in a ligand-free state and in complexes with nucleotides ADPNP, ADP, and ATP, divalent cations magnesium and manganese, and inositol polyphosphates IP, 5-IP, and 1,5-IP. Substrate binding elicits a switch from open to closed conformations, entailing a disordered-to-ordered transition and a rearrangement or movement of two peptide segments that form a binding site for the phospho-acceptor. Our structures, along with structure-guided mutagenesis, fortify understanding of the mechanism and substrate specificity of Asp1 kinase, and they extend and complement structural and functional studies of the orthologous human kinase PPIP5K2.
Topics: Humans; Adenosine Diphosphate; Adenosine Triphosphate; Diphosphates; Inositol Phosphates; Multifunctional Enzymes; Phosphotransferases (Phosphate Group Acceptor); Pyrophosphatases; Schizosaccharomyces; Schizosaccharomyces pombe Proteins
PubMed: 36468882
DOI: 10.1128/mbio.03087-22 -
Frontiers in Bioengineering and... 2023NADH pyrophosphatase, a hydrolase catalyzing the phosphate bond of NADH to reduced nicotinamide mononucleotide, has potential applications in the food, cosmetic and...
NADH pyrophosphatase, a hydrolase catalyzing the phosphate bond of NADH to reduced nicotinamide mononucleotide, has potential applications in the food, cosmetic and pharmaceutical industry. Here, we investigated the effects of vector screening, promoter and RBS strategies on NADH pyrophosphatase expression and protein engineering on its enzymatic activity and thermal stability. In this study, we describe a NADH pyrophosphatase derived from (). Strategies focusing on expression regulation including screening vectors, optimizing promoters and ribosome binding sites were utilized to enhance the productivity of (1.8 U/mL). Moreover, protein engineering was adopted to further improve the catalytic properties of , achieving 3.3-fold higher activity and 3.6-fold greater thermostability at 50°C. Furthermore, fermentation for the combined mutant R148A-H149E () production in a 7 L fermenter was implemented and the enzyme activity of reached 33.0 U/mL. Finally, the was applied in the catalysis of NADH with the highest NMNH yield of 16.65 g/L. In conclusion, we constructed a commercially available genetically engineered strain with high activity and thermal stability of NADH pyrophosphatase, laying a broad foundation for the biocatalytic industrial production of NMNH and expand its application range.
PubMed: 37082214
DOI: 10.3389/fbioe.2023.1159965 -
Biochemistry and Cell Biology =... Oct 2022Inorganic pyrophosphatase (iPPase) is an enzyme that cleaves pyrophosphate into two phosphate molecules. This enzyme is an essential component of in vitro transcription...
Inorganic pyrophosphatase (iPPase) is an enzyme that cleaves pyrophosphate into two phosphate molecules. This enzyme is an essential component of in vitro transcription (IVT) reactions for RNA preparation as it prevents pyrophosphate from precipitating with magnesium, ultimately increasing the rate of the IVT reaction. Large-scale RNA production is often required for biochemical and biophysical characterization studies of RNA, therefore requiring large amounts of IVT reagents. Commercially purchased iPPase is often the most expensive component of any IVT reaction. In this paper, we demonstrate that iPPase can be produced in large quantities and high quality using a reasonably generic laboratory facility and that laboratory-purified iPPase is as effective as commercially available iPPase. Furthermore, using size exclusion chromatography coupled with multi-angle light scattering and dynamic light scattering, analytical ultracentrifugation, and small-angle X-ray scattering, we demonstrate that yeast iPPase can form tetramers and hexamers in solution as well as the enzymatically active dimer. Our work provides a robust protocol for laboratories involved with RNA in vitro transcription to efficiently produce active iPPase, significantly reducing the financial strain of large-scale RNA production.
Topics: Diphosphates; Inorganic Pyrophosphatase; Magnesium; Pyrophosphatases; RNA
PubMed: 35926232
DOI: 10.1139/bcb-2022-0118