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The Journal of Clinical Investigation Feb 1965
HIGH ENERGY PHOSPHATE COMPOUNDS IN THE MYOCARDIUM DURING EXPERIMENTAL CONGESTIVE HEART FAILURE. PURINE AND PYRIMIDINE NUCLEOTIDES, CREATINE, AND CREATINE PHOSPHATE IN NORMAL AND IN FAILING HEARTS.
Topics: Adenine Nucleotides; Adenosine Triphosphate; Animals; Biochemical Phenomena; Biochemistry; Cardiomegaly; Chromatography; Coenzymes; Creatine; Creatinine; Cytosine Nucleotides; Dogs; Flavin-Adenine Dinucleotide; Guanine Nucleotides; Heart Failure; Metabolism; Myocardium; NAD; Nucleotides; Phosphates; Phosphocreatine; Pulmonary Valve Stenosis; Purines; Pyrimidine Nucleotides; Research; Uracil Nucleotides
PubMed: 14260162
DOI: 10.1172/JCI105135 -
Canadian Journal of Biochemistry Feb 1965
Topics: Adenine Nucleotides; Autoradiography; Chromatography; Guanine Nucleotides; Imidazoles; Nucleotides; Phosphates; Phosphorus Isotopes; Purines; Pyrimidine Nucleotides; Research; Triticum; Uracil Nucleotides
PubMed: 14325974
DOI: 10.1139/o65-031 -
Biochemical Pharmacology Oct 1982Biopsy specimens were obtained from patients treated with N-(phosphonacetyl)-L-aspartate (PALA) in a phase I clinical trial. Activities of aspartate carbamoyltransferase...
Biopsy specimens were obtained from patients treated with N-(phosphonacetyl)-L-aspartate (PALA) in a phase I clinical trial. Activities of aspartate carbamoyltransferase (ACTase), the target enzyme, in ten specimens before treatment varied from 0.4 to 1.7 units/mg. PALA was measured in protein-free extracts of thirteen specimens by inhibition of rat ACTase. At 1.5 to 145 hr after doses of 1 to 6 g/m2, PALA concentrations were 0.9 to 89 micrograms/g; at 4 hr or later the tissue concentrations were similar to those in plasma (five samples). The observed inhibition of ACTase (17-87%) correlated with the PALA concentrations. Pyrimidine nucleotides were decreased (relative to purine nucleotides) in nine to ten specimens, by 16-72%. ACTase partially purified from human spleen had a Km for carbamoyl phosphate of 20.6 microM and the Ki for PALA was 0.011 microM. The results suggest that inhibition of ACTase by PALA affects the concentration of pyrimidine nucleotides in human tumors in a dose-dependent manner.
Topics: Antimetabolites, Antineoplastic; Aspartate Carbamoyltransferase; Aspartic Acid; Drug Evaluation; Humans; Kinetics; Neoplasms; Organophosphorus Compounds; Phosphonoacetic Acid; Proteins; Pyrimidine Nucleotides; Uridine Triphosphate
PubMed: 7150358
DOI: 10.1016/0006-2952(82)90567-6 -
The Journal of Biological Chemistry Sep 1977Carbamyl-P synthetase (EC 2.7.2.9), aspartate transcarbamylase (EC 2.1.3.2), and dihydro-orotase (EC 3.5.2.3), the first three enzymes of the de novo pathway for...
Carbamyl-P synthetase (EC 2.7.2.9), aspartate transcarbamylase (EC 2.1.3.2), and dihydro-orotase (EC 3.5.2.3), the first three enzymes of the de novo pathway for synthesis of pyrimidine nucleotides, have been co-purified as a single oligomeric protein from a mutant line of hamster cells selected for its ability to resist N-(phosphonacetyl)-L-aspartate (PALA), a potent and specific inhibitor of aspartate transcarbamylase. All three enzymes overaccum,late in the mutant cells (Kempe, T.D., Swyryd, E.A., Bruist, M., and Stark, G.R. (1976) Cell 9, 541-550) and the oligomer represents nearly 10% of the total cellular protein. Tens of milligrams of oligomer have been purified to homogeneity by a simple and rapid procedure, with recovery of about 50% of all three activities. The pure protein contains only one size of polypeptide, Mr approximately 200,000, as revealed by electrophoresis in danaturing gels. All three enzyme activities are associated with this polypeptide, indicating that it is multifunctional. Further evidence for a multifunctional protein is provided by titration of the oligomer with radioactive PALA, which reveals that the number of PALA binding sites approximately equals the number of polypeptide chains. The isolated multifunctional protein is a mixture of trimers and hexamers.
Topics: Aspartate Carbamoyltransferase; Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing); Cell Line; Dihydroorotase; Electrophoresis, Polyacrylamide Gel; Molecular Weight; Multienzyme Complexes; Protein Denaturation; Pyrimidine Nucleotides; Ultracentrifugation
PubMed: 19472
DOI: No ID Found -
Nucleic Acids Research Mar 2010Cytokinins are important plant hormones, and their biosynthesis most begins with the transfer of isopentenyl group from dimethylallyl diphosphate (DMAPP) to the N6-amino...
Crystal structure and substrate specificity of plant adenylate isopentenyltransferase from Humulus lupulus: distinctive binding affinity for purine and pyrimidine nucleotides.
Cytokinins are important plant hormones, and their biosynthesis most begins with the transfer of isopentenyl group from dimethylallyl diphosphate (DMAPP) to the N6-amino group of adenine by either adenylate isopentenyltransferase (AIPT) or tRNA-IPT. Plant AIPTs use ATP/ADP as an isopentenyl acceptor and bacterial AIPTs prefer AMP, whereas tRNA-IPTs act on specific sites of tRNA. Here, we present the crystal structure of an AIPT-ATP complex from Humulus lupulus (HlAIPT), which is similar to the previous structures of Agrobacterium AIPT and yeast tRNA-IPT. The enzyme is structurally homologous to the NTP-binding kinase family of proteins but forms a solvent-accessible channel that binds to the donor substrate DMAPP, which is directed toward the acceptor substrate ATP/ADP. When measured with isothermal titration calorimetry, some nucleotides displayed different binding affinities to HlAIPT with an order of ATP > dATP approximately ADP > GTP > CTP > UTP. Two basic residues Lys275 and Lys220 in HlAIPT interact with the beta and gamma-phosphate of ATP. By contrast, the interactions are absent in Agrobacterium AIPT because they are replaced by the acidic residues Asp221 and Asp171. Despite its structural similarity to the yeast tRNA-IPT, HlAIPT has evolved with a different binding strategy for adenylate.
Topics: Alkyl and Aryl Transferases; Aspartic Acid; Catalytic Domain; Crystallography, X-Ray; Humulus; Models, Molecular; Purine Nucleotides; Pyrimidine Nucleotides; RNA, Transfer; Rhizobium; Substrate Specificity
PubMed: 20007608
DOI: 10.1093/nar/gkp1093 -
Ryoikibetsu Shokogun Shirizu 1998
Review
Topics: 5'-Nucleotidase; Diagnosis, Differential; Humans; Purine-Pyrimidine Metabolism, Inborn Errors; Pyrimidine Nucleotides
PubMed: 9590109
DOI: No ID Found -
Biotechnology Progress 2011The presence of purines and pyrimidines bases, nucleosides, and nucleotides in the culture medium has shown to differently affect the growth of a Chinese hamster ovary...
The presence of purines and pyrimidines bases, nucleosides, and nucleotides in the culture medium has shown to differently affect the growth of a Chinese hamster ovary (CHO) cell line producing the secreted form of the human placental alkaline phosphatase enzyme (SEAP; Carvalhal et al., Biotech Prog. 2003;19:69-83). CHO, BHK, as well as Sf9 cell growth was clearly reduced in the presence of purines but was not affected by pyrimidines at the concentrations tested. The knowledge about the mechanisms by which nucleotides exert their effect when present outside the cells remains very incomplete. The catabolism of both extracellular purines and pyrimidines was followed during the culture of CHO cells. Purines/pyrimidines nucleotides added at a concentration of 1 mM to the culture medium decreased to negligible concentrations in the first 2 days. Purine and pyrimidine catabolism originated only purinic and pyrimidic end-products, respectively. The comparison between AMP catabolism in serum-free cultures (CHO cells expressing Factor VII and Sf9 cells) and in cultures containing serum (CHO cells expressing SEAP and BHK cells expressing Factor VII) showed that AMP extracellular catabolism is mediated by both cells and enzymes present in the serum. This work shows that the quantification of purines and pyrimidines in the culture medium is essential in animal cell culture optimization. When using AMP addition as a chemical cell growth strategy for recombinant protein production improvement, AMP extracellular concentration monitoring allows the optimization of the multiple AMP addition strategy for a prolonged cell culture duration with high specific productivity.
Topics: Adenosine Monophosphate; Animals; Cell Line; Cell-Free System; Chromatography, High Pressure Liquid; Cricetinae; Culture Media; Purine Nucleotides; Pyrimidine Nucleotides
PubMed: 21695809
DOI: 10.1002/btpr.656 -
Biochimica Et Biophysica Acta Nov 1976The 5-thio and 5-methylmercurithio derivatives of UTP, dUTP and dCTP have been synthesized and tested as substrates for nucleic acid polymerases. The 5-thio-nucleotides...
The 5-thio and 5-methylmercurithio derivatives of UTP, dUTP and dCTP have been synthesized and tested as substrates for nucleic acid polymerases. The 5-thio-nucleotides were polymerized inefficiently by both RNA polymerase and DNA polymerase I of Escherichia coli. The 5-methylmercurithio derivatives of dUTP and dCTP were, however, utilized by DNA polymerase I, an enzyme insensitive to mercurial compounds, although they were potent inhibitors of all other polymerases tested. While polymers containing the 5-thio substituent possess structural abnormalities, most likely interstrand disulfide bridges, polymers containing 5-methylmercurithio groups appear normal. The latter polynucleotides are readily separated from non-sulfated polymers by chromatography on mercuriagarose.
Topics: DNA-Directed DNA Polymerase; DNA-Directed RNA Polymerases; Dithiothreitol; Escherichia coli; Kinetics; Methylmercury Compounds; Nucleic Acid Denaturation; Pyrimidine Nucleotides; Spectrophotometry, Ultraviolet; Sulfhydryl Compounds; Templates, Genetic
PubMed: 791373
DOI: 10.1016/0005-2787(76)90350-6 -
The Journal of Biological Chemistry May 1956
Topics: Animals; Mammals; Nucleotides; Pyrimidine Nucleotides
PubMed: 13319363
DOI: No ID Found -
Journal of Biomolecular NMR May 2003Triple-resonance two-dimensional H6/H5(C4N)H and C6/C5(C4N)H experiments are described that provide through-bond H6/H5 or C6/C5 to imino/amino correlations in pyrimidine...
Triple resonance experiments for the simultaneous correlation of H6/H5 and exchangeable protons of pyrimidine nucleotides in 13C,15N-labeled RNA applicable to larger RNA molecules.
Triple-resonance two-dimensional H6/H5(C4N)H and C6/C5(C4N)H experiments are described that provide through-bond H6/H5 or C6/C5 to imino/amino correlations in pyrimidine bases in (13)C,(15)N-labeled RNA. The experiments simultaneously transfer H6/H5 magnetization by an INEPT step to the C6/C5 nuclei and by homonuclear CC- and heteronuclear CN-TOCSY steps via the intervening C4 nucleus to the N3/N4 nuclei and then by a reverse INEPT step to the imino/amino hydrogens. The sensitivity of these experiments is high as demonstrated using a 30-nucleotide pyrimidine rich RNA at a concentration of 0.9 mM at temperatures of 10 degrees C and 25 degrees C. This indicates the general applicability of the experiments and the possibility to obtain correlations for imino resonances in non-canonical regions of the target RNA.
Topics: Base Sequence; Carbon Isotopes; Isotope Labeling; Magnetic Resonance Spectroscopy; Models, Molecular; Nitrogen Isotopes; Nucleic Acid Conformation; Pyrimidine Nucleotides; RNA
PubMed: 12766404
DOI: 10.1023/a:1023040520291