Thomas K R, Olivera B M
J Biol Chem. 1978 Jan 25;253(2):424-9.
A homopolymer system has been developed to examine the digestion strategies of DNA exonucleases. Escherichia coli exonuclease I and lambda-exonuclease, are processive enzymes. However, T7 exonuclease, spleen exonuclease, E. coli exonuclease III, the 3' leads to 5'-exonuclease of T4 DNA polymerase, and both the 3' leads to 5' and the 5' leads to 3' activity of E. coli DNA polymerase I dissociate frequently from the substrate during the course of digestion. Regions of duplex DNA are a dissociation signal for exonuclease I.
已开发出一种均聚物系统来研究DNA核酸外切酶的消化策略。大肠杆菌核酸外切酶I和λ核酸外切酶是持续合成酶。然而，T7核酸外切酶、脾核酸外切酶、大肠杆菌核酸外切酶III、T4 DNA聚合酶的3'至5'核酸外切酶活性以及大肠杆菌DNA聚合酶I的3'至5'和5'至3'活性在消化过程中经常从底物上解离。双链DNA区域是核酸外切酶I的解离信号。
