中度嗜热菌Deinococcus geothermalis的自发突变特征  

CHARACTERIZATION OF SPONTANEOUS MUTATIONS IN A MODERATE THERMOPHILE Deinococcus geothermalis

作　　者：马婷婷[1] 汪虎[1] 田兵[1] 华跃进[1] 

机构地区：[1]浙江大学原子核农业科学研究所/农业部核农学重点开放实验室,浙江杭州310029

出　　处：《核农学报》2011年第5期898-903,共6页Journal of Nuclear Agricultural Sciences

基　　金：国家"863"项目(2007AA021305);国家自然科学基金重点资助项目(30830006);重大新药创制科技重大专项(2009ZXJ09001-034);转基因生物新品种培育重大专项项目(2009ZX08009-075B);农业部行业专项(200803034)

摘　　要：通过rpoB/Rifr系统研究了Deinococcus geothermalis DSM 11300的自发突变模式。在30℃和50℃分别获得自发突变株并测定其相应温度条件下的突变频率和突变率。结果表明,30℃培养下该菌的自发突变率是50℃培养的2倍,二者有22个不同的突变位点,表明温度影响了该菌的自发突变。此外,50℃培养的细菌SOD和CAT酶活性均强于30℃,其SOD和CAT基因的表达水平也是30℃培养的1.5倍之多。说明D.gethermails在30℃培养时突变率上升与其细胞内抗氧化酶的表达和活性下降相关。A spontaneous mutation pattern in Deinococcus geothermalisDSM 11300 was measured by using the rpoB/Rifr system.To investigate the relationship between spontaneous mutation and growth temperature,spontaneous mutants were generated at culture temperatures of 30℃ and 50℃,and the corresponding mutation frequencies and rates were measured.The results showed that the bacteria cultured at 30℃ had a two-fold higher spontaneous mutation rate than that cultured at 50℃,and 22 mutation sites differed between the bacteria grown at 30℃ and 50℃,indicating that temperature affected on the spontaneous mutation of D.geothermalis.The activities of SOD and CAT of D.geothermalisgrown at 50℃ were significantly higher than those grown at 30℃,and the SODand CATgene expression levels in D.geothermalisat 50℃ were about 2-fold higher than those grown at 30℃.These results indicated that the elevation of mutation rate when grown at 30℃ was associated with a decline of the antioxidant enzymes in D.geothermalis.

关 键 词：rpoB/Rifr 自发突变 突变率 

分 类 号：Q937[生物学—微生物学]