文章基本信息

标题：Effect of NaN3 on Oxygen-Dependent Lethality of UV-A in Escherichia coli Mutants Lacking Active Oxygen-Defence and DNA-Repair Systems.
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作者：KAZUMASA YAMADA ; TETSUYOSHI ONO ; HAJIME NISHIOKA 等
期刊名称：Journal of Radiation Research
印刷版ISSN：0449-3060
电子版ISSN：1349-9157
出版年度：1996
卷号：37
期号：1
页码：29-37
DOI：10.1269/jrr.37.29
摘要：Escherichia coli mutants which lack defence systems against such active oxygen forms as OxyR (Δ oxyR ), superoxide dismutase (SOD) ( sodA and sodB ) and catalase ( katE and katG ) are sensitive to UV-A lethality under aerobic conditions, whereas OxyR- and SOD-mutants have resistance under anaerobic conditions and in the presence of sodium azide (NaN 3 ) during irradiation. UV-A induces lipid peroxidation in the Δ oxyR mutant, which is suppressed by NaN 3 . These results suggest that UV-A generates 1 O 2 or the hydroxyl radical to produce lipid peroxides intracellularly in the Δ oxyR mutant and that O 2 - stress may be generated in the sodAB mutant after 8 hr of exposure to UV-A. The sensitivities of such DNA repair-deficient mutants as recA ind- and uvrA to UV-A also were examined and compared. These mutants are sensitive to UV-A lethality under aerobic conditions but show only slight resistance under anaerobic conditions or in the presence of NaN 3 during irradiation. We conclude that NaN 3 protects these mutant cells from oxygen-dependent UV-A lethality.
关键词：UV-A; active oxygen; NaN 3 ; E; coli