Takahashi M, Bertrand-Burggraf E, Fuchs R P, Nordén B
Institut de Biologie Moléculaire et Cellulaire du CNRS, Strasbourg, France.
FEBS Lett. 1992 Dec 7;314(1):10-2. doi: 10.1016/0014-5793(92)81448-u.
The interaction between UvrABC excinuclease from Escherichia coli and ultraviolet light-(UV) damaged DNA was studied by flow linear dichroism. The dichroism signal from DNA was drastically decreased in intensity upon incubation with UvrA and UvrB or whole enzyme in the presence of effector ATP. The change was specific for UV-damaged DNA, and a concluded suppressed DNA orientation suggests the wrapping of DNA around the protein. The incubation with the UvrC subunit alone also somewhat reduces the signal, however, in this case the change was smaller and not specific for UV-damaged DNA. The structural modification of DNA, promoted by the (UvrA2-UvrB) complex, probably facilitates or stabilizes the interaction of the UvrC subunit with DNA for the excision.
利用流动线性二色性研究了来自大肠杆菌的UvrABC核酸外切酶与紫外线(UV)损伤DNA之间的相互作用。在效应物ATP存在的情况下,与UvrA和UvrB或全酶一起孵育时,DNA的二色性信号强度急剧下降。这种变化对UV损伤的DNA具有特异性,得出的DNA取向受抑制表明DNA围绕蛋白质缠绕。单独与UvrC亚基孵育也会在一定程度上降低信号,然而,在这种情况下,变化较小且对UV损伤的DNA不具有特异性。由(UvrA2-UvrB)复合物促进的DNA结构修饰可能促进或稳定UvrC亚基与DNA的相互作用以进行切除。