Abstract
The DNA-damaging agent mitomycin C ( MMC ) was found to induce B-phase cell cycle arrest ( equivalent to G1 arrest in eukaryotes ) in the radiation-resistant bacterium Deinococcus radiodurans IR. The arrested cells were able to grow in a synchronous fashion when they washed followed by incubating in a fresh medium. D. radiodurans IR cells synchronized at different cell cycle phases exhibited different UV and MMC resistance, with a decreasing order of B> C> D (C and D are equivalent to S and G2 phase of eukaryotes, respectively ). Similar decreasing resistance does not occur when synchronized IR cells subjected to heat killing. Synchronized cultures were also subjected to cell volume determination by using Coulter size analyzer. The results showed that a newly born daughter cell grows in the B phase with increasing about 30﹪of its original volume, 40﹪in the C phase and 30﹪in the D phase. This is the first attempt to apply flow cytometry (FCM) in studying D. radiodurans and to apply both of Coulter size analyzer and FCM in studying cell cycle characteristics of a microorganism.2. 英文摘要………………………………………………...…..23. 緒言…………………………………………………………34. 材料與方法…………………………………………………..55. 結果…………………………………………………………...86. 討論………………………………………………………….157. 參考文獻…………………………………………………….208. 圖………………………………………………………………i9. 附錄………………………………………………………..xiii