Meijer A J, von Woerkom G M, Eggelte T A
Biochim Biophys Acta. 1976 Apr 9;430(1):53-61. doi: 10.1016/0005-2728(76)90221-8.
Phthalonic acid is a powerful inhibitor of alpha-oxoglutarate transport in mitochondria. This conclusion is based on the following observations: 1. Phthalonic acid inhibits the oxidation of alpha-oxoglutarate but has no effect on the oxidation of glutamate or cis-aconitate. 2. With arsenite present, phthalonic acid inhibits the oxidation of glutamate plus malate and of cis-aconitate plus malate. Under these conditions alpha-oxoglutarate accumulates inside the mitochondria. With glutamate plus malate as substrates the inhibition is competitive with malate with a Ki value of 20 muM. 3. Phthalonic acid inhibits the oxidation of intramitochondrial NAD(P)H by alpha-oxoglutarate plus ammonia. The inhibition is competitive with respect to alpha-oxoglutarate with a Ki of 30 muM. 4. Phthalonic acid inhibits the exchange between extramitochondrial alpha-oxoglutarate and intramitochondrial malate.
邻苯二甲酸是线粒体中α-酮戊二酸转运的强效抑制剂。这一结论基于以下观察结果：1. 邻苯二甲酸抑制α-酮戊二酸的氧化，但对谷氨酸或顺乌头酸的氧化没有影响。2. 存在亚砷酸盐时，邻苯二甲酸抑制谷氨酸加苹果酸以及顺乌头酸加苹果酸的氧化。在这些条件下，α-酮戊二酸在线粒体内积累。以谷氨酸加苹果酸作为底物时，这种抑制作用与苹果酸具有竞争性，Ki值为20μM。3. 邻苯二甲酸抑制α-酮戊二酸加氨对线粒体内NAD(P)H的氧化。这种抑制作用相对于α-酮戊二酸具有竞争性，Ki为30μM。4. 邻苯二甲酸抑制线粒体外α-酮戊二酸与线粒体内苹果酸之间的交换。
