Interaction of the RecA protein of Escherichia coli with single-stranded oligodeoxyribonucleotides.
The RecA protein of Escherichia coli performs a number of ATP-dependent, in vitro reactions and is a DNA-dependent ATPase. Small oligodeoxyribonucleotides were used as DNA cofactors in a kinetic analysis of the ATPase reaction. Polymers of deoxythymidilic acid as well as oligonucleotides of mixed base composition stimulated the RecA ATPase activity in a length-dependent fashion. Both the initial rate and the extent of the reaction were affected by chain length. Full activity was seen with chain lengths > or = 30 nt. Partial activity was seen with chain lengths of 15-30 nt. The lower activity of shorter oligonucleotides was not simply due to a reduced affinity for DNA, since effects of chain length on KmATP and the Hill coefficient for ATP hydrolysis were also observed. The results also suggested that single-stranded DNA secondary structure frequently affects the ATPase activity of RecA protein with oligodeoxyribonucleotides.
Bianco
P R
PR
Department of Biochemistry and Molecular Biology, University of Texas Medical School, Houston 77225, USA.
Weinstock
G M
GM
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D004277:DNA, Single-Stranded / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D007700:Kinetics; D011485:Protein Binding; D011938:Rec A Recombinases / Q000378:metabolism*
D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D000255:Adenosine Triphosphate; D011938:Rec A Recombinases; D000251:Adenosine Triphosphatases