有機磷化合物為一種神經毒素，廣泛用於製造農藥及殺蟲劑，而有機磷農藥也是國內目前使用最廣泛、用量最大宗的農藥，但過度使用此類化合物不只對人體身體造成危害，其廢棄物對於環境也會造成影響，而現行對於有機磷酸酯化合物及其廢棄物的處理方式還維持在傳統的焚燒或掩埋，但是這兩種方法都會對環境造成汙染，如何在不造成額外汙染又有效率的處理此類化合物變成一個重要的課題。
近十年來，運用酵素降解有機磷化合物的方法受到許多人注意。有機磷酸酯水解酶源自於微生物Pseudomonas diminuta，具有降解機磷化合物的功能，可應用於有機磷農藥的降解及檢測，是一種具有高發展潛力的酵素。本研究之目的為藉由分子生物學中的基因轉殖技術製備一個以外膜囊泡為載體的重組蛋白用於降解有機磷化合物，希望藉由OMVs特殊的結構可以賦予所表達蛋白特殊的功能，而其結果顯示其研究所表達之OPH可以有效率的降解有機磷化合物，而其所建立的重組蛋白具有較高的熱穩定度且即使連續使用十次也依然維持80%以上的活性。

Organophosphate compounds (OPs) are a group of highly toxic compounds that are widely used as agricultural and domestic pesticides. The overuse of OPs not only caused environmental pollution but also increased the risk of human health. However, current techniques for detoxifying OPs rely on harsh chemical treatment. With the developments in biotechnology, enzymatic methods are increasingly used for detection and destruction of OPs. Organophosphorus hydrolase (OPH) isolated from soil microorganisms is one of the candidates that possesses the capability of hydrolyzing OPs efficiently. However, practical applications of large-scale enzymatic degradation have always been limited by the cost and stability of OPH. As a cost-effective alternative, enzyme immobilization is one of the generally used techniques to increase the reaction efficiency, enzyme stability and reusability of enzyme by immobilizing enzyme to the support. Different types of materials ranging from inorganic supports , nanomaterials to biomaterials have been utilized as enzyme supports. Outer membrane vesicles (OMVs) are 20 to 200 nm proteoliposomes, naturally derived from the outer membrane of gram-negative bacteria as part of their life cycle. Recently, OMVs have been utilized as platform nanomaterial supports to the fusion of heterologous proteins for enhanced functionality thus creating “designer OMVs.” However, a drawback of using designer OMVs is that they could not be isolated and purified easily due to its nanoscale size. To solve the problem, we engineered designer OMVs having two functionalities; OP degradation, and cellulose binding activities. The resulting bi-functional designer OMVs immobilized on cellulose exhibited enhanced OPH activity, recyclability, operational stability, and can be recovered from the reaction mixture via centrifugation.

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