辐射对耐辐射球菌(Deinococcus radiodurans)抗氧化酶活性提高的影响

ENHANCEMENT OF ANTIOXIDANT ENZYMES' ACTIVITIES BY IRRADIATION IN Deinococcus radiodurans

利用低剂量 ( 5 0～ 1 5 0 0Gy)的60 Coγ射线辐照处于稳定早期的耐辐射球菌培养物 ,考察了辐照剂量和辐照后培养时间对菌体中抗氧化酶 ,即超氧化物歧化酶 (SOD)和过氧化氢酶 (CAT)含量的影响。结果表明 ,在一定辐照条件 ( 2 0 0～ 1 0 0 0Gy)下 ,经过 30～ 60min的辐照后培养 ,菌体中SOD和CAT酶活性显著提高 ,其中 1 0 0 0Gy辐照且辐照后培养 30min的SOD酶活性达到1 49 69U mg ,CAT酶活性达 1 85 5 0 1U mg。分别比对照 (未辐照 )提高了 75 5 9%和 60 98%。低水平辐照 ( 0～ 1 0 0 0Gy)对菌体生物量的影响不明显。

Cultures of Deinococcus radiodurans at early stage of stable phase were treated by low doses of γ ray (50～1500Gy) and the effects of γ ray irradiation on activities of antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT), were investigated. The results indicated that SOD and CAT activities in cells increased significantly during the post incubation (30～60min) after the irradiation (200～1000Gy). At 30min after the irradiation of 1000Gy, SOD and CAT activities reached 149 69 U/mg and 1855 01 U/mg, respectively, which were 75.59% and 60 98% higher than those of controls (without irradiation) respectively. Low doses of irradiation (0～1000Gy) were found to have little effects on cell mass.