本研究透過引入2-酮戊二酸:鐵氧還蛋白氧化還原酶（2-oxoglutarate: ferredoxin oxidoreductase, OGOR）之外源基因，以蘋果酸（malate）作為碳源，並以硝酸鈉（NaNO_3）的作為電子接受者，設計了一套以 Arduino 為核心的無線傳輸與光密度感測的生物反應系統，利用該系統進行實驗室適應性演化實驗。實驗將原本的異營型的大腸桿菌菌株經過146天的適應性演化後突變成在厭氧條件下可將二氧化碳（CO_2）作為無機碳源使用的混營型菌株，此外，該菌株在演化過程中，藉助氫氣（H_2），開發出了新的能量來源途徑，能以蘋果酸（malate）作為電子供體，並搭配硝酸鈉（NaNO_3）作為電子接受者，即使在缺乏二氧化碳（CO_2）和氫氣（H_2）的厭氧條件下，仍能進行顯著的生長。
本研究中使用的生物反應器具備無線傳輸功能，電子零件安裝便捷且易於維護。此外，由於系統體積小巧，可以在裝上無線充電裝置後於不同的設備之間移植。此系統能夠支持多種實驗方式和電子零件模組，在不同的氣體條件下進行長期不間斷的氣體量測及菌株培養等實驗。

This study introduced a foreign gene encoding 2-oxoglutarate:ferredoxin oxidoreductase (OGOR) into Escherichia coli, using malate as a carbon source and NaNO_3 as an electron acceptor. We designed an Arduino-based bioreactor system with wireless transmission and optical density sensing for laboratory adaptive evolution experiments. Over 146 days, the original heterotrophic E. coli evolved into a mixotrophic strain capable of utilizing CO_2 as an inorganic carbon source under anaerobic conditions. Furthermore, the strain, with the assistance of H_2 during its evolution, developed a new energy source pathway, utilizing malate as an electron donor and sodium nitrate as an electron acceptor. Even under anaerobic conditions lacking both CO_2 and H_2, it can still achieve significant growth.
The bioreactor featured wireless transmission for easy installation and maintenance of components. Its compact design also supported wireless charging, facilitating transfer across different devices. This flexible system enabled long-term, uninterrupted gas measurement and bacterial culture under varying environmental conditions.

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