Oba K, Uritani I
J Biochem. 1975 Jun;77(6):1205-13.
Pyruvate decarboxylase [2-oxo acid carboxy-lyase, EC 4.1.1.1] was isolated from sweet potato roots and was partially purified from healthy and diseased tissues. There was no appreciable difference in properties between the enzymes from healthy and diseased tissues. The molecular weight of the enzyme was found to be 240,000 by polyacrylamide gel electrophoresis. Since sodium dodecyl sulfate polyacrylamide gel electrophoresis gave a molecular weight of 60,000 for the monomeric form of the enzyme, it is likely that sweet potato pyruvate decarboxylase contains 4 single polypeptide chains. The optimal pH of the decarboxylation reaction was 6.1--6.6. The Lineweaver-Burk double reciprocal plot curved upward, and the Hill coefficient was more than 1, with low concentrations of pyruvate. The enzyme was localized in the cytosol fraction. The activity of the enzyme increased in response to black-rot fungus infection, but decreased in response to cutting.
丙酮酸脱羧酶[2-氧代酸羧基裂解酶，EC 4.1.1.1]从甘薯根中分离得到，并从健康和患病组织中进行了部分纯化。来自健康和患病组织的酶在性质上没有明显差异。通过聚丙烯酰胺凝胶电泳发现该酶的分子量为240,000。由于十二烷基硫酸钠聚丙烯酰胺凝胶电泳给出该酶单体形式的分子量为60,000，因此甘薯丙酮酸脱羧酶可能包含4条单多肽链。脱羧反应的最佳pH为6.1--6.6。Lineweaver-Burk双倒数图向上弯曲，且在低浓度丙酮酸时希尔系数大于1。该酶定位于胞质溶胶部分。该酶的活性在响应黑腐病菌感染时增加，但在响应切割时降低。
