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PLoSONE：食品安全快速檢測技術獲進展

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近日，美國《公共科學圖書館-綜合》在線報道了乙酰膽堿酯酶酵母表面展示系統的構建及其在有機磷和氨基甲酸酯類農藥殘留快速檢測中的應用 。該成果由中科院上海生科院營養所王慧研究組完成，系統核心技術已獲中國發明專利授權，研發的檢測試劑盒即將在上海開展示范應用 。
有機磷和氨基甲酸酯類殺蟲劑是我國使用的主要農藥品種之一，也是造成農產品污染最嚴重的農藥品種之一 。酶抑制法是有機磷和氨基甲酸酯類殺蟲劑最常用的快檢方法 。目前主要使用的檢測酶類為乙酰膽堿酯酶，但其穩定性不足且價格昂貴 。
王慧研究組構建了乙酰膽堿酯酶的酵母表面展示系統 。表達在酵母表面的重組乙酰膽堿酯酶表現出高活性，在酶抑制法檢測分析中較市售乙酰膽堿酯酶的靈敏度更高 。同時，用酵母細胞作為酶固定化載體，避免了游離酶性質不穩定、極易失活等缺點，也可使后續酶的分離純化過程更為簡易，顯著降低成本 。
【PLoSONE：食品安全快速檢測技術獲進展】生物谷推薦的英文摘要

PLoS ONEdoi: 10.1371/journal.pone.0072986
Surface Display of Recombinant Drosophila melanogaster Acetylcholinesterase for Detection of Organic Phosphorus and Carbamate Pesticides
Jingquan Li，#1，3 Qian Ba，#1，3 Jun Yin，#1 Songjie Wu，1 Fangfang Zhuan，1 Songci Xu，1 Junyang Li，1 Joelle K. Salazar，2 Wei Zhang，2 and Hui Wang1，3，*
Acetylcholinesterase (AChE) is commonly used for the detection of organophosphate (OP) and carbamate (CB) insecticides. However，the cost of this commercially available enzyme is high，making high-throughput insecticide detection improbable. In this study we constructed a new AChE yeast expression system in Saccharomyces cerevisiae for the expression of a highly reactive recombinant AChE originating from Drosophila melanogaster (DmAChE). Specifically，the coding sequence of DmAChE was fused with the 3′-terminal half of an α-agglutinin anchor region，along with an antigen tag for the detection of the recombinant protein. The target sequence was cloned into the yeast expression vector pYes-DEST52，and the signal peptide sequence was replaced with a glucoamylase secretion region for induced expression. The resultant engineered vector was transformed into S. cerevisiae. DmAChE was expressed and displayed on the cell surface after galactose induction. Our results showed that the recombinant protein displayed activity comparable to the commercial enzyme. We also detected different types of OP and CB insecticides through enzyme inhibition assays，with the expressed DmAChE showing high sensitivity. These results show the construction of a new yeast expression system for DmAChE，which can subsequently be used for detecting OP and CB insecticides with reduced economic costs.