Kiguchi S
Acta Med Okayama. 1983 Apr;37(2):85-91. doi: 10.18926/AMO/32415.
Metabolism of 3-mercaptopyruvate was investigated using homogenates of rat heart, liver and kidney. When 3-mercaptopyruvate was incubated with heart homogenate, L-cysteine, L-alanine, S-(2-hydroxy-2-carboxyethylthio)-L-cysteine and 3-mercaptolactate were produced. At the same time, a decrease in the amounts of L-glutamate and L-aspartate was demonstrated. These results indicate that 3-mercaptopyruvate was converted to L-cysteine by cysteine aminotransferase (EC 2.6.1.3), to 3-mercaptolactate by lactate dehydrogenase (EC 1.1.1.27), and to pyruvate by 3-mercaptopyruvate sulfurtransferase (EC 2.8.1.2), and that HCETC and L-alanine were formed from these products. In the presence of liver homogenate, 3-mercaptopyruvate was mainly metabolized by 3-mercaptopyruvate sulfurtransferase; production of L-cysteine was small and HCETC was not formed. The metabolism of 3-mercaptopyruvate in the presence of kidney homogenate was intermediate between heart and liver: a fair amount of L-cysteine was formed, but HCETC was not produced. A peak which corresponds to L-cysteine-glutathione disulfide on the chromatogram of amino acid analysis was present when 3-mercaptopyruvate was incubated with heart or liver homogenate, but not with kidney homogenate.
利用大鼠心脏、肝脏和肾脏的匀浆研究了3-巯基丙酮酸的代谢。当3-巯基丙酮酸与心脏匀浆一起孵育时，会产生L-半胱氨酸、L-丙氨酸、S-(2-羟基-2-羧乙基硫基)-L-半胱氨酸和3-巯基乳酸。同时，L-谷氨酸和L-天冬氨酸的量有所减少。这些结果表明，3-巯基丙酮酸通过半胱氨酸转氨酶（EC 2.6.1.3）转化为L-半胱氨酸，通过乳酸脱氢酶（EC 1.1.1.27）转化为3-巯基乳酸，并通过3-巯基丙酮酸硫转移酶（EC 2.8.1.2）转化为丙酮酸，并且这些产物形成了HCETC和L-丙氨酸。在肝脏匀浆存在的情况下，3-巯基丙酮酸主要通过3-巯基丙酮酸硫转移酶进行代谢；L-半胱氨酸的生成量较少，且未形成HCETC。在肾脏匀浆存在的情况下，3-巯基丙酮酸的代谢介于心脏和肝脏之间：形成了相当数量的L-半胱氨酸，但未产生HCETC。当3-巯基丙酮酸与心脏或肝脏匀浆一起孵育时，氨基酸分析色谱图上出现了一个与L-半胱氨酸-谷胱甘肽二硫化物相对应的峰，但与肾脏匀浆一起孵育时则没有。
