Inhibition of RecA protein by the Escherichia coli RecX protein: modulation by the RecA C terminus and filament functional state.
The RecX protein is a potent inhibitor of RecA activities. We identified several factors that affect RecX-RecA interaction. The interaction is enhanced by the RecA C terminus and by significant concentrations of free Mg(2+) ion. The interaction is also enhanced by an N-terminal His(6) tag on the RecX protein. We conclude that RecX protein interacts most effectively with a RecA functional state designated A(o) and that the RecA C terminus has a role in modulating the interaction. We further identified a C-terminal point mutation in RecA protein (E343K) that significantly alters the interaction between RecA and RecX proteins.
Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Dr., Madison, WI 53706-1544, USA.
Julia C
JC
Drees
Shelley L
SL
Lusetti
Michael M
MM
Cox
D000251:Adenosine Triphosphatases / Q000737:chemistry; D000255:Adenosine Triphosphate / Q000737:chemistry; D001426:Bacterial Proteins / Q000737:chemistry / Q000502:physiology*; D002021:Buffers; D003001:Cloning, Molecular; D004247:DNA / Q000737:chemistry; D004277:DNA, Single-Stranded / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial; D006868:Hydrolysis; D007477:Ions; D008274:Magnesium / Q000737:chemistry; D017354:Point Mutation; D017434:Protein Structure, Tertiary; D011938:Rec A Recombinases / Q000037:antagonists & inhibitors* / Q000737:chemistry; D013997:Time Factors
D001426:Bacterial Proteins; D002021:Buffers; D004277:DNA, Single-Stranded; D029968:Escherichia coli Proteins; D007477:Ions; C430523:RecX protein, Xanthomonas campestris; D000255:Adenosine Triphosphate; D004247:DNA; D011938:Rec A Recombinases; D000251:Adenosine Triphosphatases; D008274:Magnesium