Pope C N, Padilla S S
Neurotoxicology Division, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711.
Biochem Pharmacol. 1989 Jan 1;38(1):181-8. doi: 10.1016/0006-2952(89)90166-4.
Neurotoxic esterase (neuropathy target enzyme, NTE) is an enzyme whose irreversible inhibition is the apparent first step in the induction of organophosphorus-induced delayed neuropathy. NTE is an integral membrane protein and thus must be solubilized before isolation can be attempted. This study describes solubilization of active chicken brain NTE with the nondenaturing detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS) and characterization of the detergent-solubilized enzyme by gel exclusion chromatography. When detergent-solubilized membranes were chromatographed on Sepharose gel exclusion media, NTE activity eluted with an apparent molecular weight of 880-970 kD. When [3H]diisopropylphosphorofluoridate-radiolabeled membranes and unlabeled microsomal membranes were CHAPS-solubilized, combined and chromatographed on Sepharose 4B, NTE activity coeluted with two radiolabeled proteins (Mr = 148 kD and Mr = 112 kD using sodium dodecyl sulfate-polyacrylamide gel electrophoresis with reducing conditions). Another radiolabeled protein (Mr = 92 kD) coeluted exclusively with inhibitor-resistant esterase activity. This study provides strong evidence that the 148 and 112 kD proteins are subunits of a multicomponent NTE complex.
神经毒性酯酶（神经病靶标酶，NTE）是一种酶，其不可逆抑制是有机磷诱导的迟发性神经病发生过程中明显的第一步。NTE是一种整合膜蛋白，因此在尝试分离之前必须先进行增溶。本研究描述了用非变性去污剂3-[(3-胆酰胺丙基)二甲基铵]-1-丙烷磺酸盐（CHAPS）增溶活性鸡脑NTE，并通过凝胶排阻色谱法对去污剂增溶的酶进行表征。当去污剂增溶的膜在琼脂糖凝胶排阻介质上进行色谱分析时，NTE活性以表观分子量880 - 970 kD洗脱。当用[³H]二异丙基氟磷酸酯放射性标记的膜和未标记的微粒体膜用CHAPS增溶、合并并在琼脂糖4B上进行色谱分析时，NTE活性与两种放射性标记的蛋白质（在还原条件下使用十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳，Mr = 148 kD和Mr = 112 kD）共洗脱。另一种放射性标记的蛋白质（Mr = 92 kD）仅与抗抑制剂酯酶活性共洗脱。本研究提供了有力证据，表明148 kD和112 kD的蛋白质是多组分NTE复合物的亚基。
