大肠杆菌DNA聚合酶缺陷型突变体中的DNA修复

DNA repair in DNA-polymerase-deficient mutants of Escherichia coli.

作者信息

Smith D W, Tait R C, Harris A L

出版信息

Basic Life Sci. 1975;5B:473-81. doi: 10.1007/978-1-4684-2898-8_8.

Abstract

Escherichia coli mutants deficient in DNA polymerase I, in DNA polymerases I and II, or in DNA polymerase III can efficiently and completely execute excision-repair and postreplication repair of the UV-damaged DNA at 30 degrees C and 43 degrees C when assayed by alkaline sucrose gradients. Repair by Pol I- and Pol I-, Pol II- cells is inhibited by 1-beta-D-arabinofuranosylcytosine (araC) at 43 degrees C but not at 30 degrees C, whereas that by Pol III- cells is insensitive to araC at any temperature. Thus, either Pol I or Pol III is required for complete and efficient repair, and in their absence Pol II mediates a limited, incomplete dark repair of UV-damaged DNA.

摘要

当通过碱性蔗糖梯度进行检测时，缺乏DNA聚合酶I、缺乏DNA聚合酶I和II或缺乏DNA聚合酶III的大肠杆菌突变体，在30摄氏度和43摄氏度时能够高效且完全地执行紫外线损伤DNA的切除修复和复制后修复。在43摄氏度而非30摄氏度时，Pol I-细胞以及Pol I-、Pol II-细胞的修复会受到1-β-D-阿拉伯呋喃糖基胞嘧啶（araC）的抑制，而Pol III-细胞的修复在任何温度下对araC均不敏感。因此，完全且高效的修复需要Pol I或Pol III，在它们缺失的情况下，Pol II介导紫外线损伤DNA的有限、不完全的暗修复。