Constantopoulos G, Barranger J A
Biochem Med. 1983 Feb;29(1):51-6. doi: 10.1016/0006-2944(83)90053-4.
Extracts of pigeon liver acetone powder showed, by a radiochemical method, considerable pyruvate decarboxylating activity. The 10-30% saturated ammonium sulfate fraction of these extracts required the addition of CoA, NAD+, and TPP for maximum pyruvate decarboxylating activity and presumably contained the pyruvate dehydrogenase complex (PDHC). The activity in the 40-60% saturated ammonium sulfate fraction had no requirement for CoA and/or NAD+ but had an absolute requirement for TPP. In similar preparations obtained from fresh pigeon liver, the PDHC activity was found in the 0-30% saturated ammonium sulfate fraction and only a small amount of pyruvate decarboxylating activity (independent of CoA and NAD+) was found in the 40-60% saturated ammonium sulfate fraction. The pyruvate decarboxylating activity which is found in the 40-60% saturated ammonium sulfate fraction of these extracts and has an absolute requirement for TPP, may represent pyruvate dehydrogenase (E1, EC 1.2.4.1), probably derived from PDHC by the acetone treatment at pH 7.8, or aging of the preparation.
通过放射化学方法发现，鸽肝丙酮粉提取物具有相当可观的丙酮酸脱羧活性。这些提取物中硫酸铵饱和度为10%-30%的部分，为使丙酮酸脱羧活性达到最大值，需要添加辅酶A、烟酰胺腺嘌呤二核苷酸（NAD⁺）和硫胺素焦磷酸（TPP），推测其中含有丙酮酸脱氢酶复合体（PDHC）。硫酸铵饱和度为40%-60%的部分中的活性对辅酶A和/或烟酰胺腺嘌呤二核苷酸没有需求，但对硫胺素焦磷酸有绝对需求。在从新鲜鸽肝获得的类似制剂中，丙酮酸脱氢酶复合体活性存在于硫酸铵饱和度为0%-30%的部分，而在硫酸铵饱和度为40%-60%的部分中仅发现少量丙酮酸脱羧活性（不依赖于辅酶A和烟酰胺腺嘌呤二核苷酸）。在这些提取物中硫酸铵饱和度为40%-60%的部分中发现的、对硫胺素焦磷酸有绝对需求的丙酮酸脱羧活性，可能代表丙酮酸脱氢酶（E1，EC 1.2.4.1），可能是由于在pH 7.8条件下进行丙酮处理或制剂老化，从丙酮酸脱氢酶复合体衍生而来。
