PURIFICATION AND CHARACTERIZATION OF SALUTARIDINE - NADPH 7-OXIDOREDUCTASE FROM PAPAVER-SOMNIFERUM
PURIFICATION AND CHARACTERIZATION OF SALUTARIDINE - NADPH 7-OXIDOREDUCTASE FROM PAPAVER-SOMNIFERUM
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DOI：
10.1016/s0031-9422(00)90793-3
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发表时间：
1993-09-01
期刊：
影响因子：
3.8
通讯作者：
ZENK, MH
中科院分区：
文献类型：
--
作者：
GERARDY, R;ZENK, MH
在罂粟细胞培养物和分化的植物中发现了一种酶，其使用NADPH作为共底物立体选择性地将罂粟生物碱salutaridine还原为（7S）-salutaridinol（=正向反应）。使用一个七步的程序，从细胞悬浮培养物中纯化的酶的表观电泳同质性。分离的酶是M（r）52+/-3 X 10（3）的单一多肽，显示出4.4的等电点。生理正向反应的最适pH为6.0-6.5，逆反应的最适pH为9.0-9.5。Salutaridine和NADPH的表观K（m）值（正向反应）分别为23 μ M和125 μ M。该酶介导NADPH的pro-S氢化物（B型）向salutaridine的C-7的高度底物特异性转移。还原酶是一种胞质酶。对含异喹啉的植物和细胞培养物的筛选表明，该酶仅存在于罂粟和大苞牡丹中。由氧化还原酶催化的还原步骤使得salutaridinol分子准备好形成氧化物桥，其表征吗啡和相关的鸦片生物碱。
An enzyme which stereoselectively reduces the Papaver alkaloid, salutaridine, to (7S)-salutaridinol (=forward reaction) using NADPH as cosubstrate was discovered in Papaver somniferum cell cultures and differentiated plants. Using a seven-step procedure, the enzyme was purified from cell suspension cultures to apparent electrophoretic homogeneity. The isolated enzyme is a single polypeptide of M(r) 52+/-3 x 10(3) displaying an isoelectric point of 4.4. The physiological forward reaction has a pH optimum at 6.0-6.5, the reverse reaction at pH 9.0-9.5. The apparent K(m) values (forward reaction) for salutaridine and NADPH are 23 muM and 125 muM, respectively. The enzyme mediates the highly substrate-specific transfer of the pro-S hydride (B-type) of NADPH to C-7 of salutaridine. The reductase is a cytosolic enzyme. Screening of isoquinoline-containing plants and cell cultures demonstrated that the enzyme occurs only in P. somniferum and P. bracteatum. The reductive step catalysed by the oxidoreductase renders the salutaridinol molecule ready for the formation of the oxide bridge which characterizes morphine and related opium alkaloids.