本實驗以大腸桿菌作為SOS紅色螢光蛋白微生物感測器，此生物感測器可以偵測到DNA損傷藥劑便以紅色螢光蛋白作為DNA受損指標。其設計方式為個別以不同的啟動子(PrecA, PsulA, and PdinH)後面接上紅色螢光蛋白序列當作信號基因，設計完的生物感測器分別加入兩種DNA損傷藥劑:絲裂黴素以及萘啶酸，之後分別用了三種不同的儀器進行偵測，此三種儀器分別為: 多功能盤式分析系統(所有細胞一起偵測)、光學顯微鏡、流式細胞儀(對單一細胞進行偵測)。SOS紅色螢光蛋白微生物感測器可以簡單不繁雜的步驟偵測出DNA損傷藥劑。

E.coli SOS-RFP biosensors which express red fluorescent protein as a signal protein under the control of recA, sulA, and dinH gene promoters in SOS response were constructed for detection of DNA damage and evaluation of DNA damaging agents. Two kinds of DNA damaging agents, which were mitomycin C(MMC), and nalidixic acid(NA), were tested using our E.coli SOS-RFP biosensors cells. We used three techniques to detect responses of biosensors , including microplate reader(detection of whole cells), microscope, and flow cytometry(detection of single cells). The SOS-RFP bacterial biosensors provide a specific and simple method for detecting DNA damaging agents.

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