title: Characterization of 2'(3')-trinitrophenyl-ATP as an inhibitor of ATP-dependent initiation complex formation between the DNA polymerase III holoenzyme and primed DNA.
abstract: We have identified 2'(3')-trinitrophenyl-ATP to be an inhibitor of the ATP-dependent initiation complex formation reaction between the Escherichia coli DNA polymerase III holoenzyme and primed DNA. The inhibitor is specific for the initiation stage; once initiation complexes are formed the subsequent elongation reaction is unaffected. Three ATP-dependent DNA polymerase III holoenzyme reactions can be independently assayed: the ATP-dependent formation of initiation complexes, ATP binding, and the primed DNA-dependent hydrolysis of ATP. Trinitrophenyl ATP inhibits all three reactions to a similar extent with an apparent Ki between 6 and 15 microM in the presence of 5 microM ATP. This suggests all of these reactions are related and that they proceed through a common ATP-binding site. We include an improved purification of the DNA polymerase III holoenzyme in this report.
mesh_terms: D000255:Adenosine Triphosphate / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology*; D001665:Binding Sites; D004247:DNA / Q000378:metabolism*; D004258:DNA Polymerase III / Q000037:antagonists & inhibitors* / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology; D006868:Hydrolysis; D019384:Nucleic Acid Synthesis Inhibitors
chemical_list: C009587:2',3'-O-(2,4,6-trinitrophenyl)adenosine 5'-triphosphate; D019384:Nucleic Acid Synthesis Inhibitors; D000255:Adenosine Triphosphate; D004247:DNA; D004258:DNA Polymerase III