title: Interactions between Escherichia coli nucleoside-diphosphate kinase and DNA.
abstract: Nucleoside-diphosphate (NDP) kinase (NTP:nucleoside-diphosphate phosphotransferase) catalyzes the reversible transfer of gamma-phosphates from nucleoside triphosphates to nucleoside diphosphates through an invariant histidine residue. It has been reported that the high-energy phosphorylated enzyme intermediate exhibits a protein phosphotransferase activity toward the protein histidine kinases CheA and EnvZ, members of the two-component signal transduction systems in bacteria. Here we demonstrate that the apparent protein phosphotransferase activity of NDP kinase occurs only in the presence of ADP, which can mediate the phosphotransfer from the phospho-NDP kinase to the target enzymes in catalytic amounts (approximately 1 nm). These findings suggest that the protein kinase activity of NDP kinase is probably an artifact attributable to trace amounts of contaminating ADP. Additionally, we show that Escherichia coli NDP kinase, like its human homologue NM23-H2/PuF/NDP kinase B, can bind and cleave DNA. Previous in vivo functions of E. coli NDP kinase in the regulation of gene expression that have been attributed to a protein phosphotransferase activity can be explained in the context of NDP kinase-DNA interactions. The conservation of the DNA binding and DNA cleavage activities between human and bacterial NDP kinases argues strongly for the hypothesis that these activities play an essential role in NDP kinase function in vivo.
authors.affiliation: Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544-1014, USA.
authors.forename: Mikhail N
authors.initials: MN
authors.lastname: Levit
authors.forename: Bozena M
authors.initials: BM
authors.lastname: Abramczyk
authors.forename: Jeffry B
authors.initials: JB
authors.lastname: Stock
authors.forename: Edith H
authors.initials: EH
authors.lastname: Postel
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D001426:Bacterial Proteins; D001665:Binding Sites; D002384:Catalysis; D004247:DNA / Q000737:chemistry* / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins; D000071677:Histidine Kinase; D006801:Humans; D007700:Kinetics; D008565:Membrane Proteins / Q000378:metabolism; D000072236:Methyl-Accepting Chemotaxis Proteins; D008956:Models, Chemical; D009097:Multienzyme Complexes / Q000378:metabolism; D009701:Nucleoside-Diphosphate Kinase / Q000737:chemistry* / Q000378:metabolism*; D010766:Phosphorylation; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D015398:Signal Transduction; D013329:Structure-Activity Relationship
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins; D009097:Multienzyme Complexes; D000244:Adenosine Diphosphate; D004247:DNA; D000071677:Histidine Kinase; C000607608:cheA protein, E coli; C057843:envZ protein, E coli; D009701:Nucleoside-Diphosphate Kinase