隨著世界人口的成長，發展可替代能源以減低對化石能源的需求已是人類文明對未來發展的共識，生質能源以農業廢棄物作為原料，在生產能源的同時還可避免過去燃燒、掩埋帶來的汙染。以生物轉化法進行生物質的水解具有反應條件溫和與易於操作等優點，僅需要投入可大量分泌生物質水解酶之菌株於反應槽中即可，然而若環境中無相關底物存在，菌體仍會持續表達非必須基因，最終能量耗盡而導致死亡。為改善上述缺點，本研究設計了兩種系統，在環境中存在不同多醣生物質時，可分別轉錄不同報告基因，以期達到感測之目的，在確認感測效果正常後，將此報告基因替換為水解酶基因，可使其在生物轉化法應用上更具實用性。系統一以糖類誘導型啟動子作為設計元件，當環境中存在木質纖維素時，將會被持續少量分泌至胞外的纖維素水解酶與半纖維素水解酶水解，而後各自產物糖類將誘導不同啟動子開啟下游螢光蛋白轉錄，目前已達成對木聚醣之感測，對纖維素的感測亦完成了系統的建立，並持續調整以提升偵測效果；而另一系統參考Clostridium thermocellum在艱困環境下發展出的生存策略，利用σI2 轉錄因子與 RsgI2跨膜蛋白之間的交互作用力，使其可在環境中存在纖維素時，釋放轉錄因子並表達相關啟動子下游之綠螢光蛋白以達成感測之目的，先前的研究已建構了具相關基因之質體與確立排列調控方式，並逐一確認元件的效果，本研究專注於跨膜蛋白的正確表達與感測能力。

The global population growth leads to a consensus in human that the development of alternative energy to reduce reliance on fossil fuels is necessary. Biomass energy, which uses agricultural waste as raw material, has the advantage of generating energy and reducing pollution. Biocatalytic biomass hydrolysis provides mild reaction conditions and eazy operation. However, no matter there are any substrates in the environment, bacteria will continue expressing non-essential genes, ultimately depleting their own energy. To address these limitations, two systems were designed in this study, enable the transcription of different reporter genes in the presence of various polysaccharide biomass.
System 1 employs sugar-inducible promoters as design elements. Hydrolitic enzyme are continuously secreted in small quantities. Once lignocellulosic is present in the environment, they will be spontaneous hydrolysis. Subsequently, the sugar products induce different promoters, initiating the transcription of downstream fluorescent proteins. The sensing of xylan has been successfully achieved, and the establishment of a cellulose sensing system has been completed, with ongoing adjustments to enhance the detection effectiveness. The second system take the survival strategy of Clostridium thermocellum. Utilizes the interaction between the σI2 transcription factor and the RsgI2 transmembrane protein to release the transcription factor in the presence of cellulose. Previous research has constructed plasmids containing relevant genes, established the arrangement and regulation methods and confirmed the effects of individual components. This study focuses on ensuring the proper expression and sensing capabilities of transmembrane proteins.

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