Rapid propagational interactions of slow binding inhibitor with RecA protein occur on the longer nucleoprotein filaments.
RecA protein is a DNA-dependent ATPase. RecA protein-mediated ATP hydrolysis occurs throughout the filamentous nucleoprotein complexes of RecA and DNA. Nucleotide analog ATP[gammaS] may not act simply as a competitive inhibitor, leading to inhibition kinetic patterns that are informative. When a mixture of ATP and ATP[gammaS] is present at the beginning of reaction, a transient phase lasting several minutes is observed in which the system approaches the state characteristic of the new ATP/ATP[gammaS] ratio. This phase consists of a burst or lag in ATP hydrolysis, depending on whether ATP or ATP[gammaS] respectively, is added first. The transition phase reflects a slow conformational change in a RecA monomer or a general adjustment in the structure of RecA filaments. The RecA filaments formed on longer DNA cofactor were more sensitive, and respond more rapidly to ATP[gammaS] than on shorter DNA cofactors.
Kim
Jong-Il
JI
Department of Food and Microbial Technology, Seoul Women's University, Seoul, Republic of Korea. jikim@swu.ac.kr
D000255:Adenosine Triphosphate / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000378:metabolism; D001667:Binding, Competitive; D004247:DNA / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D009698:Nucleoproteins / Q000378:metabolism; D011485:Protein Binding; D011938:Rec A Recombinases / Q000037:antagonists & inhibitors / Q000378:metabolism*
D009698:Nucleoproteins; C022571:adenosine 5'-O-(3-thiotriphosphate); D000255:Adenosine Triphosphate; D004247:DNA; D011938:Rec A Recombinases