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Nucleoside Diphosphate Kinase (nucleoside + diphosphate_kinase)
Selected AbstractsThe role of Ureaplasma nucleoside monophosphate kinases in the synthesis of nucleoside triphosphatesFEBS JOURNAL, Issue 8 2007Liya Wang Mollicutes are wall-less bacteria and cause various diseases in humans, animals and plants. They have the smallest genomes with low G + C content and lack many genes of DNA, RNA and protein precursor biosynthesis. Nucleoside diphosphate kinase (NDK), a house-keeping enzyme that plays a critical role in the synthesis of nucleic acids precursors, i.e. NTPs and dNTPs, is absent in all the Mollicutes genomes sequenced to date. Therefore, it would be of interest to know how Mollicutes synthesize dNTPs/NTPs without NDK. To answer this question, nucleoside monophosphate kinases (NMPKs) from Ureaplasma were studied regarding their role in the synthesis of NTPs/dNTPs. In this work, Ureaplasma adenylate kinase, cytidylate kinase, uridylate kinase and thymidylate kinase were cloned and expressed in Escherichia coli. The recombinant enzymes were purified and characterized. These NMPKs are base specific, as indicated by their names, and capable of converting (d)NMPs directly to (d)NTPs. The catalytic rates of (d)NTPs and (d)NDP synthesis by these NMPKs were determined using tritium-labelled (d)NMPs, and the rates for (d)NDP synthesis, in general, were much higher (up to 100-fold) than that of (d)NTP. Equilibrium studies with adenylate kinase suggested that the rates of NTPs/dNTPs synthesis by NMPKs in vivo are probably regulated by the levels of (d)NMPs. These results strongly indicate that NMPKs could substitute the NDK function in vivo. [source] Structure of Ynk1 from the yeast Saccharomyces cerevisiaeACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 7 2008Huabing Wang Nucleoside diphosphate kinase (NDPK) catalyzes the transfer of the ,-phosphate from nucleoside triphosphates to nucleoside diphosphates. In addition to biochemical studies, a number of crystal structures of NDPK from various organisms, including both native proteins and complexes with nucleotides or nucleotide analogues, have been determined. Here, the crystal structure of Ynk1, an NDPK from the yeast Saccharomyces cerevisiae, has been solved at 3.1,Å resolution. Structural analysis strongly supports the oligomerization state of this protein being hexameric rather than tetrameric. [source] Protein preparation, crystallization and preliminary X-ray analysis of Trypanosoma cruzi nucleoside diphosphate kinase 1ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 7 2010J. A. Gómez Barroso The flagellated protozoan parasite Trypanosoma cruzi is the aetiological agent of Chagas disease. Nucleoside diphosphate kinases (NDPKs) are enzymes that are involved in energy management and nucleoside balance in the cell. T. cruzi TcNDPK1, a canonical isoform, was overexpressed in Escherichia coli as an N-terminally poly-His-tagged fusion protein and crystallized. Crystals grew after 72,h in 0.2,M MgCl2, 20% PEG 3350. Data were collected to 3.5,Å resolution using synchrotron X-ray radiation at the National Synchrotron Light Laboratory (Campinas, Brazil). The crystals belonged to the trigonal space group P3, with unit-cell parameters a = b = 127.84, c = 275.49,Å. Structure determination is under way and will provide relevant information that may lead to the first step in rational drug design for the treatment of Chagas disease. [source] Production, purification, crystallization and preliminary X-ray diffraction studies of the nucleoside diphosphate kinase b from Leishmania majorACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 11 2009Celisa Caldana Costa Tonoli Nucleoside diphosphate kinases (NDKs; EC 2.7.4.6) play an essential role in the synthesis of nucleotides from intermediates in the salvage pathway in all parasitic trypanosomatids and their structural studies will be instrumental in shedding light on the biochemical machinery involved in the parasite life cycle and host,parasite interactions. In this work, NDKb from Leishmania major was overexpressed in Escherichia coli, purified to homogeneity and crystallized using the sitting-drop vapour-diffusion method. The NDK crystal diffracted to 2.2,Å resolution and belonged to the trigonal crystal system, with unit-cell parameters a = 114.2, c = 93.9,Å. Translation-function calculations yielded an unambiguous solution in the enantiomorphic space group P3221. [source] Nm23-H1 promotes adhesion of CAL 27 cells in vitroMOLECULAR CARCINOGENESIS, Issue 9 2009ica Bago Abstract nm23-H1 was found to diminish metastatic potential of carcinoma cell lines and therefore was placed in the group of metastatic suppressor genes. Its protein product has a function of a nucleoside diphosphate kinase (NDPK) as well as protein kinase and nuclease. Though it was found that Nm23-H1 is involved in many cellular processes, it is still not known how it promotes metastatic suppressor activity. Since the process of metastasis is dependent on adhesion properties of cells, the goal of our work was to describe the adhesion properties of CAL 27 cells (oral squamous cell carcinoma of the tongue) overexpressing FLAG/nm23-H1. In our experiments, cells overexpressing nm23-H1 show reduced migratory and invasive potential. Additionally, cells overexpressing nm23-H1 adhere stronger on substrates (collagen IV and fibronectin) and show more spread morphology than the control cells. Results obtained by EGF induction of migration revealed that the adhesion strength predetermined cell response to chemoattractant and that Nm23-H1, in this cell type, does not interfere with, EGF induced, Ras signaling pathway. These data contribute to the overall knowledge about nm23-H1 and its role in cell adhesion, migration, and invasion, especially in oral squamous cell carcinoma. © 2009 Wiley-Liss, Inc. [source] Exclusion of 5 functional candidate genes for distal hereditary motor neuropathy type II (distal HMN II) linked to 12q24.3ANNALS OF HUMAN GENETICS, Issue 6 2001J. IROBI Distal hereditary motor neuropathies (distal HMNs) are characterised by degeneration of anterior horn cells of the spinal cord resulting in muscle weakness and atrophy. Distal HMN type II is genetically linked to chromosome 12q24.3 and located within a 13 cM region flanked by markers D12S86 and D12S340. We previously excluded the human phospholipase A2 group 1B gene (PLA2G1B) as the disease causing gene. Here, we report the mutation analysis of five other candidate genes localised within the distal HMN II region: the cytoskeletal proteins paxillin (PXN) and restin (RSN); the acidic ribosomal phosphoprotein, large P0 subunit (RPLP0); a nucleoside diphosphate kinase (NME2B); and the , 3 subunit of the voltage-gated calcium channel (CACNB3). DNA sequencing of the coding regions was performed but no disease causing mutations could be identified, hence excluding these five genes for distal HMN type II. [source] Protein preparation, crystallization and preliminary X-ray analysis of Trypanosoma cruzi nucleoside diphosphate kinase 1ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 7 2010J. A. Gómez Barroso The flagellated protozoan parasite Trypanosoma cruzi is the aetiological agent of Chagas disease. Nucleoside diphosphate kinases (NDPKs) are enzymes that are involved in energy management and nucleoside balance in the cell. T. cruzi TcNDPK1, a canonical isoform, was overexpressed in Escherichia coli as an N-terminally poly-His-tagged fusion protein and crystallized. Crystals grew after 72,h in 0.2,M MgCl2, 20% PEG 3350. Data were collected to 3.5,Å resolution using synchrotron X-ray radiation at the National Synchrotron Light Laboratory (Campinas, Brazil). The crystals belonged to the trigonal space group P3, with unit-cell parameters a = b = 127.84, c = 275.49,Å. Structure determination is under way and will provide relevant information that may lead to the first step in rational drug design for the treatment of Chagas disease. [source] Purification, crystallization and preliminary structural analysis of nucleoside diphosphate kinase from Bacillus anthracisACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 12 2007Gauri Misra Bacillus anthracis nucleoside diphosphate kinase (BaNdk) is an enzyme whose primary function is to maintain deoxynucleotide triphosphate (dNTP) pools by converting deoxynucleotide diphosphates to triphosphates using ATP as the major phosphate donor. Although the structures of Ndks from a variety of organisms have been elucidated, the enzyme from sporulating bacteria has not been structurally characterized to date. Crystals of the B. anthracis enzyme were grown using the vapour-diffusion method from a hanging drop consisting of 2,µl 10,mg,ml,1 protein in 50,mM Tris,HCl pH 8.0, 50,mM NaCl, 5,mM EDTA equilibrated against 500,µl reservoir solution consisting of 2.25,M ammonium formate and 0.1,M HEPES buffer pH 7.25. Diffraction data extending to 2.0,Å were collected at room temperature from a single crystal with unit-cell parameters a = b = 107.53, c = 52.3,Å. The crystals are hexagonal in shape and belong to space group P6322. The crystals contain a monomer in the asymmetric unit, which corresponds to a Matthews coefficient (VM) of 2.1,Å3,Da,1 and a solvent content of about 36.9%. [source] | ||||||||||