ISOLATION AND SOME PROPERTIES OF A CYTOSOL AND A MITOCHONDRIAL MALIC ENZYME FROM BOVINE BRAIN
ISOLATION AND SOME PROPERTIES OF A CYTOSOL AND A MITOCHONDRIAL MALIC ENZYME FROM BOVINE BRAIN
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DOI：
10.1016/0003-9861(72)90201-9
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发表时间：
1972-01-01
影响因子：
3.9
通讯作者：
FRENKEL, R
中科院分区：
文献类型：
--
作者：
FRENKEL, R
从牛脑中分离并部分纯化了两种不同的苹果酸酶同工酶。通过在不同离子强度的溶液中制备匀浆并通过提取分离的线粒体，已经确定一种同工酶（BI）位于胞质溶胶中，另一种位于线粒体中（B II）。同工酶不仅在电泳和色谱迁移率上不同，而且在动力学性质上也不同，因为只有线粒体变体在低浓度l（−）苹果酸时显示出协同性。的同工酶也表现出显着的差异，在他们的能力，催化丙酮酸还原羧化为苹果酸，因为羧化速率接近1 5的脱羧速度的胞质酶，只有1 100的线粒体同工酶。
Two distinct isozymes of malic enzyme from bovine brain have been separated and purified partially. By preparing homogenates in solutions of different ionic strength and by extracting isolated mitochondria, it has been established that one isozyme (BI) is located in the cytosol and the other in the mitochondria (B II). The isozymes differ not only in their electrophoretic and chromatographic mobilities, but also in their kinetic properties, since only the mitochondrial variant shows cooperativity at low concentrations of l (−) malate. The isozymes also show a marked difference in their capability to catalyze the reductive carboxylation of pyruvate to malate, since the carboxylation rate approaches 1 5 that of the decarboxylation velocity for the cytosol enzyme, and only 1 100 for the mitochondrial isozyme.