PLoSONE：食品安全快速检测技术获进展食品

近日，美国《公共科学图书馆-综合》在线报道了乙酰胆碱酯酶酵母表面展示系统的构建及其在有机磷和氨基甲酸酯类农药残留快速检测中的应用。该成果由中科院上海生科院营养所王慧研究组完成，系统核心技术已获中国发明专利授权，研发的检测试剂盒即将在上海开展示范应用。
有机磷和氨基甲酸酯类杀虫剂是我国使用的主要农药品种之一，也是造成农产品污染最严重的农药品种之一。酶抑制法是有机磷和氨基甲酸酯类杀虫剂最常用的快检方法。目前主要使用的检测酶类为乙酰胆碱酯酶，但其稳定性不足且价格昂贵。
王慧研究组构建了乙酰胆碱酯酶的酵母表面展示系统。表达在酵母表面的重组乙酰胆碱酯酶表现出高活性，在酶抑制法检测分析中较市售乙酰胆碱酯酶的灵敏度更高。同时，用酵母细胞作为酶固定化载体，避免了游离酶性质不稳定、极易失活等缺点，也可使后续酶的分离纯化过程更为简易，显著降低成本。
【PLoSONE：食品安全快速检测技术获进展】生物谷推荐的英文摘要

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.