Ohshima S, Sekiguchi M
J Biochem. 1975 Feb;77(2):303-11. doi: 10.1093/oxfordjournals.jbchem.a130727.
Mutants of bacteriophage T4 which exhibit increased sensitivity to ultraviolet radiation were isolated and their abilities to induce an enzyme system to excise pyrimidine dimers were examined. Among 16 mutants isolated, 12 mutants were found to be defective in inducing T4 endonuclease V, which catalyzes the formation of dimer-specific breaks in ultraviolet-irradiated DNA. A leaky v mutant, which exhibits intermediate ultraviolet sensitivity, was also isolated; the mutant induces a low level of endonuclease V and excises only a small amount of kimers in vitro. Three other mutants, as well as x and y mutants, were able to induce both T4 endonuclease V and dimer-excision enzyme (5'yields 3' exonuclease).
分离出了对紫外线辐射敏感性增加的噬菌体T4突变体，并检测了它们诱导切除嘧啶二聚体的酶系统的能力。在分离出的16个突变体中，发现有12个突变体在诱导T4内切核酸酶V方面存在缺陷，该酶催化紫外线照射的DNA中形成二聚体特异性断裂。还分离出了一个渗漏型v突变体，其对紫外线具有中等敏感性；该突变体诱导产生低水平的内切核酸酶V，并且在体外仅切除少量二聚体。另外三个突变体以及x和y突变体能够诱导T4内切核酸酶V和二聚体切除酶（5'产生3'外切核酸酶）。
