流式細胞儀是利用光照射細菌，來檢測細菌的光基因電路表現的標準方法，但是它必須先在外部誘發基因，再放進儀器中偵測基因表現，是需要耗費較多人力成本，而且實驗上也較為繁瑣。在本研究中，我們設計了一個工作體積約10ml的閃爍計數瓶的生物反應器，能夠即時偵測CCaS-CCaR光感測系統的基因表現。報導基因蛋白的光密度、螢光蛋白偵測和誘導基因的光源，由四個發光二極體和兩個光電晶體組成。經過市售偵測儀器校正之後，此實驗裝置能夠自動化操作，同時做細菌培養並記錄其生長和基因表現，不需要額外的人力操作。我們做了用不同有機物(葡萄糖、琥珀酸鹽、乙酸鹽和丙酮酸鹽)作為基本培養基的碳來源實驗，觀察其細菌生長的基因表達。還有透過連續稀釋步驟證明光基因電路調變的演化實驗。

Current standard protocol to characterize such optogenetic circuit of bacterial cells using flow cytometry in light tubes and well plates for light exposure is tedious, labor intensive and cumbersome. In this work, we engineer a bioreactor of working volume ~10 ml for in vivo, real time optogenetic characterization of E. coli with a CCaS-CCaR light sensing system. The optical density, fluorescence detection for reporter protein as well as the light input stimuli are provided by four light emitting diode sources and two photodetectors. Once calibrated, the device can cultivate the cells and record both the microbial growth and gene expression without human intervention. We measure gene expression for cell growth under different organic substrates(glucose, succinate, acetate, and pyruvate) as carbon source in minimal medium and demonstrate evolutionary tuning of optogenetic circuit by serial dilution passage.

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