Braun A, Hopper P, Grossman L
Basic Life Sci. 1975;5A:183-90. doi: 10.1007/978-1-4684-2895-7_22.
An endonuclease from Escherichia coli which acts specificially upon UV-irradiated DNA (correndonuclease II) and is absent from the uvrA and uvrB mutants has been isolated and partially chacterized. The enzyme is present in normal amounts in the urvC mutant. It elutes from phosphocellulose at about 0.25 M potassium phosphate (pH 7.5) and passes through dialysis tubing. The enzyme binds tightly to UV-irradiated DNA but does not bind to unirradiated DNA. The enzyme incises irradiated DNA to the 5' side of a pyrimidine dimer and leaves a 5'-phosphoryl terminus which can be resealed with polynucleotide ligase. The Km of the enzyme is about 1.5 X 10(-8) M dimers. Endonucleolytic activity of the enzyme is inhibited by caffeine with a KI of about 10mM.
一种来自大肠杆菌的核酸内切酶已被分离并部分表征，它特异性作用于紫外线照射过的DNA（校正核酸酶II），uvrA和uvrB突变体中不存在该酶。该酶在uvrC突变体中含量正常。它在约0.25M磷酸钾（pH 7.5）下从磷酸纤维素柱上洗脱，并能透过透析管。该酶与紫外线照射过的DNA紧密结合，但不与未照射的DNA结合。该酶在嘧啶二聚体的5'侧切割照射过的DNA，留下一个5'-磷酸末端，该末端可用多核苷酸连接酶重新封闭。该酶的Km约为1.5×10⁻⁸M二聚体。该酶的核酸内切酶活性被咖啡因抑制，抑制常数约为10mM。
