Yonezawa Y, Nishioka H
Department of Chemical Engineering and Materials Science, Doshisha University, Kyotanabe, Kyoto, Japan.
J Toxicol Environ Health A. 1999 Jun 25;57(4):237-45. doi: 10.1080/009841099157683.
Sensitivities to sunlight of Escherichia coli mutants deficient in DNA repair capacities such as excision and recombination repair and their wild-type strain were compared. Higher sensitivities to sunlight were clearly observed in the mutant than wild-type strain, indicating that exposure to sunlight induces DNA damage which is repaired by DNA repair mechanisms. In order to assess the role of generation of reactive oxygen species (ROS) in DNA damage induced by exposure to natural sunlight, the kat-sod assay was performed using E. coli mutant strains deficient in ROS scavenging enzymes such as superoxide dismutase and/or catalase. Natural sunlight induced a significant generation of ROS, suggesting a possibility that sunlight induced ROS may be involved in DNA damage in bacterial cells.
比较了缺乏DNA修复能力（如切除修复和重组修复）的大肠杆菌突变体及其野生型菌株对阳光的敏感性。明显观察到突变体对阳光的敏感性高于野生型菌株，这表明暴露于阳光会诱导DNA损伤，而这种损伤可由DNA修复机制修复。为了评估活性氧（ROS）的产生在自然阳光照射诱导的DNA损伤中的作用，使用缺乏超氧化物歧化酶和/或过氧化氢酶等ROS清除酶的大肠杆菌突变菌株进行了kat-sod测定。自然阳光诱导了大量ROS的产生，这表明阳光诱导的ROS可能参与细菌细胞中的DNA损伤。
