Amino-terminal domain interactions of lambda integrase on arm-type DNA.
In contrast to the other tyrosine recombinase family members, integrase protein (Int) of bacteriophage lambda has an additional amino-terminal domain that binds to "arm-type" DNA sequences distant from those involved in strand exchange. The homomeric interaction between neighboring amino-terminal domains of Int is contributed by R30-D71 salt-bridge in a non-equivalent manner on Holliday-junction intermediates. In this report, R30 and D71 residues were investigated in regard to Int's cooperative binding to "arm-type" DNA and the attenuating function of "arm-type" DNA. The results suggest the electrostatic interaction between residues 30 and 71 is dependent on "arm-type" DNA and contributes the "selective" inhibition of catalytic activity of lambda Int by "arm-type" DNA.
Lee
Sang Yeol
SY
Department of Life Science, Kyungwon University, San 65, Bokjeong-Dong, Sujeong-Gu, Seongnam-Si, Kyeonggi-Do 461-701, Republic of Korea. leesaye@kyungwon.ac.kr