Mowbray Sherry L, Elfström Lisa T, Ahlgren Kerstin M, Andersson C Evalena, Widersten Mikael
Department of Molecular Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Protein Sci. 2006 Jul;15(7):1628-37. doi: 10.1110/ps.051792106. Epub 2006 Jun 2.
Epoxide hydrolases catalyze the conversion of epoxides to diols. The known functions of such enzymes include detoxification of xenobiotics, drug metabolism, synthesis of signaling compounds, and intermediary metabolism. In plants, epoxide hydrolases are thought to participate in general defense systems. In the present study, we report the first structure of a plant epoxide hydrolase, one of the four homologous enzymes found in potato. The structure was solved by molecular replacement and refined to a resolution of 1.95 A. Analysis of the structure allows a better understanding of the observed substrate specificities and activity. Further, comparisons with mammalian and fungal epoxide hydrolase structures reported earlier show the basis of differing substrate specificities in the various epoxide hydrolase subfamilies. Most plant enzymes, like the potato epoxide hydrolase, are expected to be monomers with a preference for substrates with long lipid-like substituents of the epoxide ring. The significance of these results in the context of biological roles and industrial applications is discussed.
环氧化物水解酶催化环氧化物转化为二醇。这类酶的已知功能包括对外源化合物的解毒、药物代谢、信号化合物的合成以及中间代谢。在植物中，环氧化物水解酶被认为参与一般防御系统。在本研究中，我们报道了一种植物环氧化物水解酶的首个结构，它是马铃薯中发现的四种同源酶之一。该结构通过分子置换法解析，并精修至1.95埃的分辨率。对该结构的分析有助于更好地理解所观察到的底物特异性和活性。此外，与先前报道的哺乳动物和真菌环氧化物水解酶结构进行比较，揭示了不同环氧化物水解酶亚家族中底物特异性差异的基础。大多数植物酶，如马铃薯环氧化物水解酶，预计为单体，偏好具有长链类脂取代基的环氧化物环的底物。本文讨论了这些结果在生物学作用和工业应用背景下具有何种意义。
