Effects of the metabolites of the branched-chain amino acids and cysteamine on the glycine cleavage system.
Effects of the metabolites of the branched-chain amino acids and cysteamine on the glycine cleavage system.
复制标题
支链氨基酸和半胱胺代谢物对甘氨酸裂解系统的影响。
DOI：
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发表时间：
1983
期刊：
影响因子：
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通讯作者：
K. Tada
中科院分区：
文献类型：
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作者：
K. Hayasaka;K. Tada
用肝提取物研究了支链氨基酸、CoA和半胱胺（β-巯基乙胺）的十种代谢产物对甘氨酸裂解系统的影响。结果表明，替格酰辅酶A、异丁酰辅酶A、琥珀酰辅酶A、甲基丙二酰辅酶A、异戊酰辅酶A、丙酰辅酶A等辅酶A衍生物以及辅酶A本身和半胱胺对肝脏提取物的甘氨酸裂解系统有明显的抑制作用。进一步研究了从鸡肝中纯化的P-蛋白和H-蛋白催化的甘氨酸-14CO_2交换反应，结果表明，替格酰基CoA对P-蛋白的活性具有明显的竞争性抑制作用，而半胱胺则通过增加甘氨酸的Km值和改变Vmax两种途径抑制P-蛋白的活性。
The effects of ten metabolites of the branched-chain amino acids, CoA and cysteamine (beta-mercaptoethylamine), on the glycine cleavage system were investigated with the liver extracts. It was found that CoA derivatives including tiglyl CoA, isobutyryl CoA, succinyl CoA, methylmalonyl CoA, isovaleryl CoA, propionyl CoA and CoA itself and cysteamine significantly inhibited the glycine cleavage system of the liver extracts. Further studies on the glycine-14CO2 exchange catalyzed by p-protein and H-protein purified from chicken liver indicated that tiglyl CoA inhibited the activity of P-protein in an apparently competitive manner with respect to H-protein, and that cysteamine inhibited the activity of P-protein in two ways, by increasing the Km value for glycine and changing Vmax.