Oh T J, Lee C W, Kim I G
Department of Radiation Biology, Korea Atomic Energy Research Institute, Yusong, Taejon, Korea.
Microbiol Res. 1999 Sep;154(2):179-83. doi: 10.1016/S0944-5013(99)80012-3.
The SOS response of Escherichia coli strains carrying the lacZ gene fused to the polB (dinA), dinB or dinD gene were investigated after treatment with several chemical agents and gamma-radiation. The induction levels of polB::lacZ reached levels between 4.0- and 9.0-fold 120 min after treatment with nalidixic acid, H2O2 or ethanol. Pentachlorophenol did not significantly induce any din genes. gamma-Irradiation is not an inducer of polB and ethanol failed to induce dinB::lacZ and dinD::lacZ. Following irradiation with a dose of 10 Gy the responses of dinB and dinD were induced about 2.5-3.0-fold above non-irradiated dinB and dinD. We found that the responses of din::lacZ fusion genes to these genotoxins are induced in a dose-dependent manner. The polB gene showed antagonistic responses to the simultaneous treatment of nalidixic acid and H2O2 or nalidixic acid and ethanol. In addition, dinB and dinD in the presence of both nalidixic acid and H2O2 at the same time showed no synergistic responses.
在用几种化学试剂和γ射线处理后，对携带与polB（dinA）、dinB或dinD基因融合的lacZ基因的大肠杆菌菌株的SOS反应进行了研究。在用萘啶酸、过氧化氢或乙醇处理120分钟后，polB::lacZ的诱导水平达到4.0至9.0倍之间。五氯苯酚未显著诱导任何din基因。γ射线不是polB的诱导剂，乙醇也未能诱导dinB::lacZ和dinD::lacZ。在用10 Gy剂量照射后，dinB和dinD的反应比未照射的dinB和dinD诱导约2.5至3.0倍。我们发现din::lacZ融合基因对这些基因毒素的反应是以剂量依赖方式诱导的。polB基因对萘啶酸与过氧化氢或萘啶酸与乙醇的同时处理表现出拮抗反应。此外，在同时存在萘啶酸和过氧化氢的情况下，dinB和dinD没有表现出协同反应。
