The cellular location of dihydroorotate dehydrogenase: Relation to de novo biosynthesis of pyrimidines

1976 ◽  
Vol 176 (1) ◽  
pp. 82-90 ◽  
Author(s):  
Jane-Jane Chen ◽  
Mary Ellen Jones
Keyword(s):  
De Novo ◽  
Dihydroorotate Dehydrogenase ◽  
Cellular Location ◽  
De Novo Biosynthesis

scholarly journals Identification of 3,4-Dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine Derivatives as Novel Selective Inhibitors of Plasmodium falciparum Dihydroorotate Dehydrogenase

2021 ◽  
Vol 22 (13) ◽  
pp. 7236
Author(s):  
Endah Dwi Hartuti ◽  
Takaya Sakura ◽  
Mohammed S. O. Tagod ◽  
Eri Yoshida ◽  
Xinying Wang ◽  
...  
Keyword(s):  
Drug Target ◽  
De Novo ◽  
Dihydroorotate Dehydrogenase ◽  
Chemical Library ◽  
New Class ◽  
De Novo Biosynthesis ◽  
Starting Point ◽  
Novel Drugs ◽  
Low Toxicity ◽  
Fourth Step

Plasmodium falciparum’s resistance to available antimalarial drugs highlights the need for the development of novel drugs. Pyrimidine de novo biosynthesis is a validated drug target for the prevention and treatment of malaria infection. P. falciparum dihydroorotate dehydrogenase (PfDHODH) catalyzes the oxidation of dihydroorotate to orotate and utilize ubiquinone as an electron acceptor in the fourth step of pyrimidine de novo biosynthesis. PfDHODH is targeted by the inhibitor DSM265, which binds to a hydrophobic pocket located at the N-terminus where ubiquinone binds, which is known to be structurally divergent from the mammalian orthologue. In this study, we screened 40,400 compounds from the Kyoto University chemical library against recombinant PfDHODH. These studies led to the identification of 3,4-dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine and its derivatives as a new class of PfDHODH inhibitor. Moreover, the hit compounds identified in this study are selective for PfDHODH without inhibition of the human enzymes. Finally, this new scaffold of PfDHODH inhibitors showed growth inhibition activity against P. falciparum 3D7 with low toxicity to three human cell lines, providing a new starting point for antimalarial drug development.

scholarly journals Detection and location of the enzymes of de novo pyrimidine biosynthesis in mammalian spermatozoa

Reproduction ◽  
2002 ◽  
pp. 757-768 ◽  
Author(s):  
EA Carrey ◽  
C Dietz ◽  
DM Glubb ◽  
M Loffler ◽  
JM Lucocq ◽  
...  
Keyword(s):  
De Novo ◽  
Pyrimidine Biosynthesis ◽  
Dihydroorotate Dehydrogenase ◽  
Aspartate Transcarbamylase ◽  
Carbamyl Phosphate ◽  
Pyrimidine Nucleotides ◽  
Carbamyl Phosphate Synthetase ◽  
De Novo Biosynthesis ◽  
Ump Synthase ◽  
Mammalian Spermatozoa

Enzymes of the pathway for de novo biosynthesis of pyrimidine nucleotides have been reported in spermatozoa from fruitfly and mammals. The aim of the present study was to test the hypothesis that the enzymes for biosynthesis of uridine monophosphate (UMP) are concentrated near the mitochondria, which are segregated in the mid-piece of spermatozoa. Baby hamster kidney fibroblasts were compared with spermatozoa from rams, boars, bulls and men. Antibodies raised against synthetic peptides from sequences of the multienzyme polypeptides containing glutamine-dependent carbamyl phosphate synthetase, aspartate transcarbamylase and dihydroorotase (CAD) and UMP synthase, which catalyse reactions 1-3 and 5-6, respectively, were used, together with an affinity-purified antibody raised against dihydroorotate dehydrogenase (DHODH), the mitochondrial enzyme for step 4. Western blot analysis, immunofluorescent microscopy and immunoelectron microscopy confirmed that CAD and UMP synthase are found in the cytoplasm around and outside the mitochondria; DHODH is found exclusively inside the mitochondria. CAD was also located in the nucleus, where it has been reported in the nuclear matrix, and in the cytoplasm, apparently associated with the cytoskeleton. It is possible that CAD in the cytoplasm has a role unconnected with pyrimidine biosynthesis.

scholarly journals Structural and Biochemical Features of Eimeria tenella Dihydroorotate Dehydrogenase, a Potential Drug Target

Genes ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1468
Author(s):  
Dan Sato ◽  
Endah Dwi Hartuti ◽  
Daniel Ken Inaoka ◽  
Takaya Sakura ◽  
Eri Amalia ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Drug Target ◽  
De Novo ◽  
Binding Pocket ◽  
Severe Form ◽  
Eimeria Tenella ◽  
Potential Drug Target ◽  
Dihydroorotate Dehydrogenase ◽  
Potential Drug ◽  
De Novo Biosynthesis

Dihydroorotate dehydrogenase (DHODH) is a mitochondrial monotopic membrane protein that plays an essential role in the pyrimidine de novo biosynthesis and electron transport chain pathways. In Eimeria tenella, an intracellular apicomplexan parasite that causes the most severe form of chicken coccidiosis, the activity of pyrimidine salvage pathway at the intracellular stage is negligible and it relies on the pyrimidine de novo biosynthesis pathway. Therefore, the enzymes of the de novo pathway are considered potential drug target candidates for the design of compounds with activity against this parasite. Although, DHODHs from E. tenella (EtDHODH), Plasmodium falciparum (PfDHODH), and human (HsDHODH) show distinct sensitivities to classical DHODH inhibitors, in this paper, we identify ferulenol as a potent inhibitor of both EtDHODH and HsDHODH. Additionally, we report the crystal structures of EtDHODH and HsDHODH in the absence and presence of ferulenol. Comparison of these enzymes showed that despite similar overall structures, the EtDHODH has a long insertion in the N-terminal helix region that assumes a disordered configuration. In addition, the crystal structures revealed that the ferulenol binding pocket of EtDHODH is larger than that of HsDHODH. These differences can be explored to accelerate structure-based design of inhibitors specifically targeting EtDHODH.

scholarly journals Antiviral Activity of Inhibitors of Pyrimidine De-Novo Biosynthesis

1996 ◽  
Vol 7 (1) ◽  
pp. 7-13 ◽  
Author(s):  
M. Wachsman ◽  
F. M. Hamzeh ◽  
N. B. Assadi ◽  
P. S. Lietman
Keyword(s):  
Antiviral Activity ◽  
Human Cytomegalovirus ◽  
Hcmv Infection ◽  
De Novo ◽  
Antiviral Effect ◽  
Pyrimidine Biosynthesis ◽  
Dihydroorotate Dehydrogenase ◽  
Dot Blot ◽  
De Novo Biosynthesis ◽  
Biosynthesis Inhibitors

Evaluation of the elevation of host cell biosynthesis of deoxynucleoside triphosphates (dNTP's) induced by human cytomegalovirus (HCMV) infection as a target for antiviral therapeutics was carried out. The concentrations of all four intracellular dNTP's rose rapidly following HCMV infection, and were markedly above baseline by 8 h post infection (p.i.). All four deoxynucleoside triphosphates remained elevated above baseline for at least 72 h p.i. The effects of inhibitors of the de-novo pathway of pyrimidine biosynthesis on HCMV viral replication-were quantified by DNA dot blot. All pyrimidine biosynthesis inhibitors examined inhibited the HCMV DNA replication at concentrations that were non-toxic to the cell. These drugs were also more effective against HCMV, which is highly dependent on host denovo synthesis, than against HSV-1 which encodes enzymes capable of increasing the supply of dNTP's. The antiviral effect of brequinar, an inhibitor of one of the enzymes of the de-novo pathway (dihydroorotate dehydrogenase), was examined to determine if it coincided with a decrease in dNTP's. HCMV-infected fibroblasts and uninfected control cells were treated with a concentration of brequinar able to inhibit HCMV DNA levels 90%. It was found that brequinar markedly lowered the levels of dTTP found in treated cells compared to untreated cells in both HCMV-infected and uninfected cells.

scholarly journals De novo Neurosteroidogenesis in Human Microglia: Involvement of the 18 kDa Translocator Protein

2021 ◽  
Vol 22 (6) ◽  
pp. 3115
Author(s):  
Lorenzo Germelli ◽  
Eleonora Da Pozzo ◽  
Chiara Giacomelli ◽  
Chiara Tremolanti ◽  
Laura Marchetti ◽  
...  
Keyword(s):  
Neurotrophic Factor ◽  
De Novo ◽  
Neuroactive Steroids ◽  
Translocator Protein ◽  
Compensatory Mechanism ◽  
Human Microglia ◽  
De Novo Biosynthesis ◽  
Murine Microglia ◽  
Synthetic Ligand ◽  
Tspo Expression

Neuroactive steroids are potent modulators of microglial functions and are capable of counteracting their excessive reactivity. This action has mainly been ascribed to neuroactive steroids released from other sources, as microglia have been defined unable to produce neurosteroids de novo. Unexpectedly, immortalized murine microglia recently exhibited this de novo biosynthesis; herein, de novo neurosteroidogenesis was characterized in immortalized human microglia. The results demonstrated that C20 and HMC3 microglial cells constitutively express members of the neurosteroidogenesis multiprotein machinery—in particular, the transduceosome members StAR and TSPO, and the enzyme CYP11A1. Moreover, both cell lines produce pregnenolone and transcriptionally express the enzymes involved in neurosteroidogenesis. The high TSPO expression levels observed in microglia prompted us to assess its role in de novo neurosteroidogenesis. TSPO siRNA and TSPO synthetic ligand treatments were used to reduce and prompt TSPO function, respectively. The TSPO expression downregulation compromised the de novo neurosteroidogenesis and led to an increase in StAR expression, probably as a compensatory mechanism. The pharmacological TSPO stimulation the de novo neurosteroidogenesis improved in turn the neurosteroid-mediated release of Brain-Derived Neurotrophic Factor. In conclusion, these results demonstrated that de novo neurosteroidogenesis occurs in human microglia, unravelling a new mechanism potentially useful for future therapeutic purposes.

scholarly journals Dietary Essential Amino Acid Restriction Promotes Hyperdipsia via Hepatic FGF21

Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1469
Author(s):  
Patricia M. Rusu ◽  
Andrea Y. Chan ◽  
Mathias Heikenwalder ◽  
Oliver J. Müller ◽  
Adam J. Rose
Keyword(s):  
Amino Acid ◽  
Growth Factor ◽  
Dietary Protein ◽  
Essential Amino Acid ◽  
De Novo ◽  
Fibroblast Growth Factor 21 ◽  
Fibroblast Growth ◽  
De Novo Biosynthesis ◽  
Dietary Requirements ◽  
Dietary Amino Acid

Prior studies have reported that dietary protein dilution (DPD) or amino acid dilution promotes heightened water intake (i.e., hyperdipsia) however, the exact dietary requirements and the mechanism responsible for this effect are still unknown. Here, we show that dietary amino acid (AA) restriction is sufficient and required to drive hyperdipsia during DPD. Our studies demonstrate that particularly dietary essential AA (EAA) restriction, but not non-EAA, is responsible for the hyperdipsic effect of total dietary AA restriction (DAR). Additionally, by using diets with varying amounts of individual EAA under constant total AA supply, we demonstrate that restriction of threonine (Thr) or tryptophan (Trp) is mandatory and sufficient for the effects of DAR on hyperdipsia and that liver-derived fibroblast growth factor 21 (FGF21) is required for this hyperdipsic effect. Strikingly, artificially introducing Thr de novo biosynthesis in hepatocytes reversed hyperdipsia during DAR. In summary, our results show that the DPD effects on hyperdipsia are induced by the deprivation of Thr and Trp, and in turn, via liver/hepatocyte-derived FGF21.

scholarly journals De novo biosynthesis of linoleic acid is widespread in parasitic wasps

2021 ◽  
Author(s):  
Bastian Broschwitz ◽  
Lorena Prager ◽  
Tamara Pokorny ◽  
Joachim Ruther
Keyword(s):  
Linoleic Acid ◽  
De Novo ◽  
Parasitic Wasps ◽  
De Novo Biosynthesis
Sign in / Sign up

Export Citation Format

Share Document