Search results

Dihydroorotate dehydrogenase (DHODH, EC 1.3.99.11), the fourth enzyme of pyrimidine de novo synthesis, is an integral flavoprotein of the inner mitchondrial membrane and is functionally connected to the respiratory chain. Here, experiments have been directed toward determining the roles of the N-terminal sequence motifs both in enzymatic properties of insect DHODH produced in vitro and the in vivo

In mammals, the four native deoxyribonucleosides are phosphorylated to the corresponding monophosphates by four deoxyribonucleoside kinases, which have specialized substrate specificities. These four enzymes are likely to originate from a common progenitor kinase. Insects appear to have only one multisubstrate deoxyribonucleoside kinase (dNK, EC 2.7.1.145), which prefers pyrimidine nucleosides, bu

In eukaryotic cells deoxyribonucleoside kinases belonging to three phylogenetic sub-families have been found: (i) thymidine kinase 1 (TK1)-like enzymes, which are strictly pyrimidine deoxyribonucleoside-specific kinases; (ii) TK2-like enzymes, which include pyrimidine deoxyribonucleoside kinases and a single multisubstrate kinase from Drosophila melanogaster (Dm-dNK); and (iii) deoxycytidine/deoxy

Deoxyribonucleoside kinases phosphorylate deoxyribonucleosides and activate a number of medically important nucleoside analogs. Here we report the structure of the Drosophila deoxyribonucleoside kinase with deoxycytidine bound at the nucleoside binding site and that of the human deoxyguanosine kinase with ATP at the nucleoside substrate binding site. Compared to the human kinase, the Drosophila ki

Mammalian dihydroorotate dehydrogenase, the fourth enzyme of pyrimidine de novo synthesis is an integral protein of the inner mitochondrial membrane that faces the intermembrane space and is functionally connected to the respiratory chain via ubiquinone. Here, we describe the first cloning and analyzing of the complete cDNA of mouse dihydroorotate dehydrogenase. Based on our recent functional expr

In contrast to all known deoxyribonucleoside kinases, a single highly efficient deoxyribonucleoside kinase from Drosophila melanogaster (Dm-dNK) is able to phosphorylate all precursor nucleosides for DNA synthesis. Dm-dNK was mutated in vitro by high-frequency random mutagenesis, expressed in the thymidine kinase-deficient Escherichia coli strain KY895 and clones were selected for sensitivity to t

In animals, dihydroorotate dehydrogenase (DHODH) is a mitochondrial protein that carries out the fourth step in de novo pyrimidine biosynthesis. Because this is the only enzyme of this pathway that is localized to mitochondria and because the enzyme is cytosolic in some bacteria and fungi, we carried out studies to understand the mode of targeting of animal DHODH and its submitochondrial localizat

The occurrence of a deoxyribonucleoside kinase in Drosophila melanogaster (Dm-dNK) with remarkably broad substrate specificity has recently been indicated (Munch-Petersen, B., Piskur, J., and Søndergaard, L. (1998) J. Biol. Chem. 273, 3926-3931). To prove that the capacity to phosphorylate all four deoxyribonucleosides is in fact associated to one polypeptide chain, partially sequenced cDNA clones

Mitochondrial dihydroorotate dehydrogenase (DHOdehase; EC 1.3.99.11) is a target of anti-proliferative, immunosuppressive and anti-parasitic agents. Here, redoxal, (2,2'-[3,3'-dimethoxy[1, 1'-biphenyl]-4,4'-diyl)diimino]bis-benzoic acid, was studied with isolated mitochondria and the purified recombinant human and rat enzyme to find out the mode of kinetic interaction with this target. Its pattern

Mitochondrially-bound dihydroorotate dehydrogenase (EC 1.3.99.11) catalyzes the fourth sequential step in the de novo synthesis of uridine monophosphate. The enzyme has been identified as or surmised to be the pharmacological target for isoxazol, triazine, cinchoninic acid and (naphtho)quinone derivatives, which exerted antiproliferative, immunosuppressive, and antiparasitic effects. Despite this

The isoxazol leflunomide (N-(4-trifluoromethylphenyl)-5-methylisoxazol-4-carboxamide) and its active metabolite A77-1726 (N-(4-trifluoromethyl)-phenyl-2-cyano-3-hydroxy-crotonic acidamide) are promising disease-modifying antirheumatic drugs now in clinical trials. The malononitrilamides MNA279 (2-cyano-3-cyclopropyl-3-oxo-(4-cyanophenyl)propionamide) MNA715(N-(4-trifluoromethyl)-phenyl-2-cyano-3-h

Mitochondrially bound dihydroorotate-ubiquinone oxidoreductase (dihydroorotate dehydrogenase, EC 1.3.99.11) catalyzes the fourth sequential step in the de novo synthesis of uridine monophosphate. Based on the recent functional expression of the complete rat dihydroorotate dehydrogenase by means of the baculovirus expression vector system in Trichoplusia ni cells, a procedure is described that allo

Mammalian dihydroorotate dehydrogenase (EC 1.3.99.11), the fourth enzyme of pyrimidine de novo synthesis is located in the mitochondrial inner membrane with functional connection to the respiratory chain. From the cDNA of rat liver dihydroorotate dehydrogenase cloned in our laboratory the first complete sequence of a mammalian enzyme was deduced. Two hydrophobic stretches centered around residues

Human mitochondrial dihydroorotate dehydrogenase (the fourth enzyme of pyrimidine de novo synthesis) has been overproduced by means of a recombinant baculovirus that contained the human cDNA fragment for this protein. After virus infection and protein expression in Trichoplusia ni cells (BTI-Tn-5B1-4), the subcellular distribution of the recombinant dihydroorotate dehydrogenase was determined by t

Mitochondrially bound dihydroorotate dehydrogenase catalyses the fourth sequential step in the de novo synthesis of uridine monophosphate. 312-bp and 983-bp regions of the human dihydroorotate dehydrogenase sequence (1496 bp) were amplified by the polymerase chain reaction, and subcloned into the expression vector pQE 32. The identity of the PCR products was verified by dideoxynucleotide sequencin

In 1962, the first thorough investigation into the expansion of the Swedish public sector was presented as a doctoral dissertation by Erik Höök. This article investigates the origin and reception of this thesis. Höök’s work has been consid ered a standard work of financial statistics. However, it attracted heavy criticism in the media and from other academics for having explained the public sector

We investigate two parallel school reforms in Sweden to assess the long-run health effects of education. One reform only increased years of schooling, while the other increased years of schooling but also removed tracking leading to a more mixed socioeconomic peer group. By differencing the effects of the parallel reforms we separate the effect of de-tracking and peers from that of more schooling.

The purpose of this paper is to increase our understanding of the governing of flood risk mitigation in advanced liberal society, through an in-depth Swedish case study. By combining social network analysis and genealogy, this paper investigates who is involved, how they organise, their modes of thinking, how they mitigate flood risk, as well as how such regime of practises have come into being. T

The aim of this study was to establish creatinine growth curves separately for males and females that can be used to adjust childhood levels of serum creatinine to corresponding adult levels. Linear regression with fractional polynomials of age as independent variable was used to construct creatinine growth curves for a reference cohort (n = 83,157 samples from Belgium and Sweden, age 2–40 years).

This article analyzes administrative practices in relation to the emergence of novel technologies. “Smart mobility” is an umbrella term used to denote the potentially disruptive changes in the transport sector relating to automatization, digitalization, and the platform economy. While this development is largely driven by industry, public administrations are engaging in a number of processes where