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International Journal of Molecular... Oct 2022Pyrophosphate (PP) is a byproduct of over 120 biosynthetic reactions, and an overabundance of PP can inhibit industrial synthesis. Pyrophosphatases (PPases) can...
Pyrophosphate (PP) is a byproduct of over 120 biosynthetic reactions, and an overabundance of PP can inhibit industrial synthesis. Pyrophosphatases (PPases) can effectively hydrolyze pyrophosphate to remove the inhibitory effect of pyrophosphate. In the present work, a thermophilic alkaline inorganic pyrophosphatase from NA1 was studied. The optimum pH and temperature of Ton1914 were 9.0 and 80 °C, respectively, and the half-life was 52 h at 70 °C and 2.5 h at 90 °C. Ton1914 showed excellent thermal stability, and its relative enzyme activity, when incubated in Tris-HCl 9.0 containing 1.6 mM Mg at 90 °C for 5 h, was still 100%, which was much higher than the control, whose relative activity was only 37%. Real-time quantitative PCR (qPCR) results showed that the promotion of Ton1914 on long-chain DNA was more efficient than that on short-chain DNA when the same concentration of templates was supplemented. The yield of long-chain products was increased by 32-41%, while that of short-chain DNA was only improved by 9.5-15%. Ton1914 also increased the yields of UDP-glucose and UDP-galactose enzymatic synthesis from 40.1% to 84.8% and 20.9% to 35.4%, respectively. These findings suggested that Ton1914 has considerable potential for industrial applications.
Topics: Thermococcus; Inorganic Pyrophosphatase; Diphosphates; Archaeal Proteins; Pyrophosphatases; Uridine Diphosphate
PubMed: 36361526
DOI: 10.3390/ijms232112735 -
MBio Jun 2022Inositol pyrophosphates (IPPs) are signaling molecules that regulate cellular phosphate homeostasis in diverse eukaryal taxa. In fission yeast, mutations that increase...
Inositol pyrophosphates (IPPs) are signaling molecules that regulate cellular phosphate homeostasis in diverse eukaryal taxa. In fission yeast, mutations that increase 1,5-IP derepress the regulon while mutations that ablate IP synthesis are hyper-repressive. Fission yeast Asp1, the principal agent of 1,5-IP dynamics, is a bifunctional enzyme composed of an N-terminal IPP kinase domain and a C-terminal IPP pyrophosphatase domain. Here we conducted a biochemical characterization and mutational analysis of the autonomous Asp1 kinase domain (aa 1-385). Reaction of Asp1 kinase with IP and ATP resulted in both IP phosphorylation to 1-IP and hydrolysis of the ATP γ-phosphate, with near-equal partitioning between productive 1-IP synthesis and unproductive ATP hydrolysis under optimal kinase conditions. By contrast, reaction of Asp1 kinase with 5-IP is 22-fold faster than with IP and is strongly biased in favor of IP synthesis versus ATP hydrolysis. Alanine scanning identified essential constituents of the active site. We deployed the Ala mutants to show that derepression of expression correlated with Asp1's kinase activity. In the case of full-length Asp1, the activity of the C-terminal pyrophosphatase domain stifled net phosphorylation of the 1-position during reaction of Asp1 with ATP and either IP or 5-IP. We report that inorganic phosphate is a concentration-dependent enabler of net IP synthesis by full-length Asp1 , by virtue of its antagonism of IP turnover. Expression of the fission yeast phosphate regulon is sensitive to the intracellular level of the inositol pyrophosphate (IPP) signaling molecule 1,5-IP. IP dynamics are determined by Asp1, a bifunctional enzyme comprising N-terminal IPP 1-kinase and C-terminal IPP 1-pyrophosphatase domains that catalyze IP synthesis and catabolism, respectively. Here, we interrogated the activities and specificities of the Asp1 kinase domain and full length Asp1. We find that reaction of Asp1 kinase with 5-IP is 22-fold faster than with IP and is strongly biased in favor of IP synthesis versus the significant unproductive ATP hydrolysis seen during its reaction with IP. We report that full-length Asp1 catalyzes futile cycles of 1-phosphate phosphorylation by its kinase component and 1-pyrophosphate hydrolysis by its pyrophosphatase component that result in unproductive net consumption of the ATP substrate. Net synthesis of 1,5-IP is enabled by physiological concentrations of inorganic phosphate that selectively antagonize IP turnover.
Topics: Acid Phosphatase; Adenosine Triphosphate; Diphosphates; Gene Expression; Inositol Phosphates; Multifunctional Enzymes; Phosphotransferases (Phosphate Group Acceptor); Pyrophosphatases; Schizosaccharomyces; Schizosaccharomyces pombe Proteins
PubMed: 35536002
DOI: 10.1128/mbio.01034-22 -
International Journal of Molecular... Feb 2022Calcium pyrophosphate (CPP) deposition disease (CPPD) is a form of CPP crystal-induced arthritis. A high concentration of extracellular pyrophosphate (ePPi) in synovial...
Calcium pyrophosphate (CPP) deposition disease (CPPD) is a form of CPP crystal-induced arthritis. A high concentration of extracellular pyrophosphate (ePPi) in synovial fluid is positively correlated with the formation of CPP crystals, and ePPi can be upregulated by ankylosis human (ANKH) and ectonucleotide pyrophosphatase 1 (ENPP1) and downregulated by tissue non-specific alkaline phosphatase (TNAP). However, there is currently no drug that eliminates CPP crystals. We explored the effects of the histone deacetylase (HDAC) inhibitors (HDACis) trichostatin A (TSA) and vorinostat (SAHA) on CPP formation. Transforming growth factor (TGF)-β1-treated human primary cultured articular chondrocytes (HC-a cells) were used to increase ePPi and CPP formation, which were determined by pyrophosphate assay and CPP crystal staining assay, respectively. Artificial substrates thymidine 5'-monophosphate p-nitrophenyl ester (p-NpTMP) and p-nitrophenyl phosphate (p-NPP) were used to estimate ENPP1 and TNAP activities, respectively. The HDACis TSA and SAHA significantly reduced mRNA and protein expressions of ANKH and ENPP1 but increased TNAP expression in a dose-dependent manner in HC-a cells. Further results demonstrated that TSA and SAHA decreased ENPP1 activity, increased TNAP activity, and limited levels of ePPi and CPP. As expected, both TSA and SAHA significantly increased the acetylation of histones 3 and 4 but failed to block Smad-2 phosphorylation induced by TGF-β1. These results suggest that HDACis prevented the formation of CPP by regulating ANKH, ENPP1, and TNAP expressions and can possibly be developed as a potential drug to treat or prevent CPPD.
Topics: Calcium Pyrophosphate; Chondrocalcinosis; Chondrocytes; Histone Deacetylase Inhibitors; Humans; Pyrophosphatases
PubMed: 35269745
DOI: 10.3390/ijms23052604 -
Pharmacological Research Sep 2023In our previous multicenter study, we delineated the inherent metabolic features of colorectal cancer (CRC). Therein, we identified a member of the ectonucleotide...
In our previous multicenter study, we delineated the inherent metabolic features of colorectal cancer (CRC). Therein, we identified a member of the ectonucleotide pyrophosphatase/ phosphodiesterase family (ENPP2) as a significant differential metabolite of CRC. In this study, the role of ENPP2 in CRC has been demonstrated using established in vitro and in vivo models including ENPP2 gene knockdown, and use of the ENPP2 inhibitor, GLPG1690. We found that CRC proliferation was decreased after either ENPP2 gene knockdown or use of ENPP2 inhibitors. We further evaluated the role of GLPG1690 in AOM/DSS-induced CRC mice via intestinal barrier function, macrophage polarization, inflammatory response and microbial homeostasis. Results of immunofluorescence staining and Western blotting showed that GLPG1690 can restore gut-barrier function by increasing the expression of tight junction proteins, claudin-1, occludin and ZO-1. M2 tumor-associated macrophage polarization and colonic inflammation were attenuated after treatment with GLPG1690 using the Azoxymethane/Dextran Sodium Sulfate (AOM/DSS) model. Moreover, 16 S rDNA pyrosequencing and metagenomic analysis showed that GLPG1690 could alleviate gut dysbiosis in mice. Furthermore, administration of GLPG1690 with antibiotics as well as fecal microbiota transplantation assays demonstrated a close link between the efficacy of GLPG1690 and the gut microbiota composition. Finally, results of metabolomic analysis implicated mainly the gut microbiota-derived metabolites of aromatic amino acids in CRC progression. These findings may provide novel insights into the development of small-molecule ENPP2 inhibitors for the treatment of CRC.
Topics: Animals; Mice; Azoxymethane; Cell Proliferation; Colitis; Colorectal Neoplasms; Dextran Sulfate; Disease Models, Animal; Gastrointestinal Microbiome; Mice, Inbred C57BL; Phosphoric Diester Hydrolases
PubMed: 37524154
DOI: 10.1016/j.phrs.2023.106877 -
Journal of Multidisciplinary Healthcare 2022It is very unusual to see evidence of arterial calcification in infants and children, and when detected, genetic disorders of calcium metabolism should be suspected.... (Review)
Review
It is very unusual to see evidence of arterial calcification in infants and children, and when detected, genetic disorders of calcium metabolism should be suspected. Generalized arterial calcification of infancy (GACI) is a hereditary disease, which is characterized by severe arterial calcification of medium sized arteries, mostly involving the media with marked intimal proliferation and ectopic mineralization of the extravascular tissues. It is caused by inactivating variants in genes encoding either ENPP1, in a majority of cases (70-75%), or ABCC6, in a minority (9-10%). Despite similar histologic appearances between ENPP1 and ABCC6 deficiencies, including arterial calcification, organ calcification, and cardiovascular calcification, mortality is higher in subjects carrying the ENPP1 versus ABCC6 variants (40% vs 10%, respectively). Overall mortality in individuals with GACI is high (55%) before the age of 6 months, with 24.4% dying in utero or being stillborn. Rare cases show spontaneous regression with age, while others who survive into adulthood often manifest musculoskeletal complications (osteoarthritis and interosseous membrane ossification), enthesis mineralization, and cervical spine fusion. Despite recent advances in the understanding of the genetic mechanisms underlying this disease, there is still no ideal therapy for the resolution of vascular calcification in GACI. Although bisphosphonates with anti-calcification properties have been commonly used for the treatment of CAGI, their benefit is controversial, with favorable results reported at one year and questionable benefit with delayed initiation of treatment. Enzyme replacement therapy with administration of recombinant form of ENPP1 prevents calcification and mortality, improves hypertension and cardiac function, and prevents intimal proliferation and osteomalacia in mouse models of ENPP1 deficiency. Therefore, newer treatments targeting genes are on the horizon. In this article, we review up to date knowledge of the understanding of GACI, its clinical, pathologic, and etiologic understanding and treatment in support of more comprehensive care of GACI patients.
PubMed: 35677616
DOI: 10.2147/JMDH.S251861 -
Cancer Letters May 2023Studies have shown that acetylation modification plays an important role in tumor proliferation and metastasis. Phospholysine phosphohistidine inorganic pyrophosphate...
Studies have shown that acetylation modification plays an important role in tumor proliferation and metastasis. Phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) is downregulated in certain tumors, as a tumor suppressor role. However, the regulation of LHPP expression and its function in nasopharyngeal carcinoma (NPC) remain unclear. In the present study, we found that LHPP was downregulated in NPC, and overexpression of LHPP inhibited the proliferation and invasion of NPC cells. Mechanistically, HDAC4 deacetylated LHPP at K6 and promoted the degradation of LHPP through TRIM21 mediated K48-linked ubiquitination. HDAC4 was confirmed to be highly expressed in NPC cells and promoted the proliferation and invasion of NPC cells through LHPP. Further research found that LHPP could inhibit the phosphorylation of tyrosine kinase TYK2, thereby inhibiting the activity of STAT1. In vivo, knockdown of HDAC4 or treatment with small molecule inhibitor Tasquinimod targeting HDAC4 could significantly inhibit the proliferation and metastasis of NPC by upregulating LHPP. In conclusion, our finding demonstrated that HDAC4/LHPP signal axis promotes the proliferation and metastasis of NPC through upregulating TYK2-STAT1 phosphorylation activation. This research will provide novel evidence and intervention targets for NPC metastasis.
Topics: Humans; Cell Line, Tumor; Cell Movement; Cell Proliferation; Gene Expression Regulation, Neoplastic; Histone Deacetylases; Nasopharyngeal Carcinoma; Nasopharyngeal Neoplasms; Repressor Proteins; Signal Transduction; Inorganic Pyrophosphatase
PubMed: 37023940
DOI: 10.1016/j.canlet.2023.216158 -
Nature Communications Mar 2024Tumor cells must rewire nucleotide synthesis to satisfy the demands of unbridled proliferation. Meanwhile, they exhibit augmented reactive oxygen species (ROS)...
Tumor cells must rewire nucleotide synthesis to satisfy the demands of unbridled proliferation. Meanwhile, they exhibit augmented reactive oxygen species (ROS) production which paradoxically damages DNA and free deoxy-ribonucleoside triphosphates (dNTPs). How these metabolic processes are integrated to fuel tumorigenesis remains to be investigated. MYC family oncoproteins coordinate nucleotide synthesis and ROS generation to drive the development of numerous cancers. We herein perform a Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based functional screen targeting metabolic genes and identified nudix hydrolase 1 (NUDT1) as a MYC-driven dependency. Mechanistically, MYC orchestrates the balance of two metabolic pathways that act in parallel, the NADPH oxidase 4 (NOX4)-ROS pathway and the Polo like kinase 1 (PLK1)-NUDT1 nucleotide-sanitizing pathway. We describe LC-1-40 as a potent, on-target degrader that depletes NUDT1 in vivo. Administration of LC-1-40 elicits excessive nucleotide oxidation, cytotoxicity and therapeutic responses in patient-derived xenografts. Thus, pharmacological targeting of NUDT1 represents an actionable MYC-driven metabolic liability.
Topics: Humans; Nudix Hydrolases; Reactive Oxygen Species; Oxidation-Reduction; Nucleotides
PubMed: 38493213
DOI: 10.1038/s41467-024-46572-6 -
Ectopic Calcification and Hypophosphatemic Rickets: Natural History of ENPP1 and ABCC6 Deficiencies.Journal of Bone and Mineral Research :... Nov 2021Generalized arterial calcification of infancy (GACI) is a rare disorder caused by ENPP1 or ABCC6 variants. GACI is characterized by low pyrophosphate, arterial...
Generalized arterial calcification of infancy (GACI) is a rare disorder caused by ENPP1 or ABCC6 variants. GACI is characterized by low pyrophosphate, arterial calcification, and high mortality during the first year of life, but the natural course and possible differences between the causative genes remain unknown. In all, 247 individual records for patients with GACI (from birth to 58.3 years of age) across 19 countries were reviewed. Overall mortality was 54.7% (13.4% in utero or stillborn), with a 50.4% probability of death before the age of 6 months (critical period). Contrary to previous publications, we found that bisphosphonate treatment had no survival benefit based on a start-time matched analysis and inconclusive results when initiated within 2 weeks of birth. Despite a similar prevalence of GACI phenotypes between ENPP1 and ABCC6 deficiencies, including arterial calcification (77.2% and 89.5%, respectively), organ calcification (65.8% and 84.2%, respectively), and cardiovascular complications (58.4% and 78.9%, respectively), mortality was higher for ENPP1 versus ABCC6 variants (40.5% versus 10.5%, respectively; p = 0.0157). Higher prevalence of rickets was reported in 70.8% of surviving affected individuals with ENPP1 compared with that of ABCC6 (11.8%; p = 0.0001). Eleven affected individuals presenting with rickets and without a GACI diagnosis, termed autosomal recessive hypophosphatemic rickets type 2 (ARHR2), all had confirmed ENPP1 variants. Approximately 70% of these patients demonstrated evidence of ectopic calcification or complications similar to those seen in individuals with GACI, which shows that ARHR2 is not a distinct condition from GACI but represents part of the spectrum of ENPP1 deficiency. Overall, this study identified an early mortality risk in GACI patients despite attempts to treat with bisphosphonates, high prevalence of rickets almost exclusive to ENPP1 deficiency, and a spectrum of heterogenous calcification and multiple organ complications with both ENPP1 and ABCC6 variants, which suggests an overlapping pathology. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). This article has been contributed to by US Government employees and their work is in the public domain in the USA.
Topics: Familial Hypophosphatemic Rickets; Humans; Infant; Multidrug Resistance-Associated Proteins; Mutation; Phosphoric Diester Hydrolases; Pyrophosphatases; Vascular Calcification
PubMed: 34355424
DOI: 10.1002/jbmr.4418 -
Veterinary Research Jan 2021Inorganic pyrophosphatase (PPase) participates in energy cycle and plays a vital role in hydrolysis of inorganic pyrophosphate (PPi) into inorganic phosphate (Pi). The...
Inorganic pyrophosphatase (PPase) participates in energy cycle and plays a vital role in hydrolysis of inorganic pyrophosphate (PPi) into inorganic phosphate (Pi). The aim of this study was to investigate the biological properties of a Trichinella spiralis PPase (TsPPase) and its role in larval molting and developmental process. The predicted TsPPase consisted of 367 amino acids with a molecular mass of 41.48 kDa and a pI of 5.76. Amino acid sequence alignment and phylogenetic analysis showed that the TsPPase gene encodes a functional family I soluble PPase with the same characteristics as prokaryotic, plant and animal/fungal soluble PPase. The rTsPPase was expressed and purified, it has the activity to catalyze the hydrolysis of PPi to Pi, and the activity was dependent on Mg, pH and temperature. The enzymatic activity of rTsPPase was significantly inhibited after its metal binding sites mutation. TsPPase was transcribed and expressed in all T. spiralis phases, especially in muscle larvae (ML) and intestinal infective larvae (IIL). Immunofluorescence assay (IFA) revealed that TsPPase was mainly located in cuticle and stichosome. When the ML and IIL were treated with TsPPase-specific siRNA-279, TsPPase expression and enzymatic activity were obviously reduced, the larval molting and development were also impeded. Intestinal IIL as well as AW burden, IIL molting rates from mice infected with siRNA-treated ML were obviously suppressed. The results indicated that rTsPPase possesses the enzymatic activity of native inorganic pyrophosphatase, and TsPPase plays an important role in development and molting process of intestinal T. spiralis larval stages.
Topics: Animals; Blotting, Western; Electrophoresis, Polyacrylamide Gel; Female; Fluorescent Antibody Technique; Inorganic Pyrophosphatase; Larva; Mice; Mice, Inbred BALB C; Molting; Mutagenesis, Site-Directed; Phylogeny; Real-Time Polymerase Chain Reaction; Sequence Alignment; Trichinella spiralis; Trichinellosis
PubMed: 33413587
DOI: 10.1186/s13567-020-00877-8 -
The New Phytologist Mar 2023In plants, inosine is enzymatically introduced in some tRNAs, but not in other RNAs or DNA. Nonetheless, our data show that RNA and DNA from Arabidopsis thaliana contain...
In plants, inosine is enzymatically introduced in some tRNAs, but not in other RNAs or DNA. Nonetheless, our data show that RNA and DNA from Arabidopsis thaliana contain (deoxy)inosine, probably derived from nonenzymatic adenosine deamination in nucleic acids and usage of (deoxy)inosine triphosphate (dITP and ITP) during nucleic acid synthesis. We combined biochemical approaches, LC-MS, as well as RNA-Seq to characterize a plant INOSINE TRIPHOSPHATE PYROPHOSPHATASE (ITPA) from A. thaliana, which is conserved in many organisms, and investigated the sources of deaminated purine nucleotides in plants. Inosine triphosphate pyrophosphatase dephosphorylates deaminated nucleoside di- and triphosphates to the respective monophosphates. ITPA loss-of-function causes inosine di- and triphosphate accumulation in vivo and an elevated inosine and deoxyinosine content in RNA and DNA, respectively, as well as salicylic acid (SA) accumulation, early senescence, and upregulation of transcripts associated with immunity and senescence. Cadmium-induced oxidative stress and biochemical inhibition of the INOSINE MONOPHOSPHATE DEHYDROGENASE leads to more IDP and ITP in the wild-type (WT), and this effect is enhanced in itpa mutants, suggesting that ITP originates from ATP deamination and IMP phosphorylation. Inosine triphosphate pyrophosphatase is part of a molecular protection system in plants, preventing the accumulation of (d)ITP and its usage for nucleic acid synthesis.
Topics: Adenosine Triphosphate; DNA; Inosine Triphosphate; Nucleic Acids; Purine Nucleotides; Pyrophosphatases; RNA
PubMed: 36464781
DOI: 10.1111/nph.18656