Campbell M T, Sutton R, Pollak J K
Eur J Biochem. 1982 Jul;125(2):401-6. doi: 10.1111/j.1432-1033.1982.tb06697.x.
A putative precursor of carbamoyl-phosphate synthase was isolated from a microsomal wash fraction and purified by high-pressure liquid chromatography. Autolytic degradation and limited proteolysis were used to characterize the putative precursor of carbamoyl-phosphate synthase and to show its similarity to the processed enzyme. The carbamoyl-phosphate synthase precursor underwent a time-dependent and concentration-dependent conversion into a dimeric or polymeric form. When labelled with 125I and incubated with foetal rat liver mitochondria the precursor was bound to the mitochondria and about 30% of the label was imported into the matrix space. This labelling required the presence of ATP and was time-dependent. Mitoplasts also imported the carbamoyl-phosphate synthase precursor. After import of the precursor, increases in carbamoyl-phosphate synthase activity could be demonstrated in foetal rat liver mitochondria.
从微粒体洗涤组分中分离出氨甲酰磷酸合成酶的一种假定前体，并通过高压液相色谱法进行纯化。利用自溶降解和有限蛋白酶解来表征氨甲酰磷酸合成酶的假定前体，并显示其与加工后的酶的相似性。氨甲酰磷酸合成酶前体经历了时间依赖性和浓度依赖性的转化，形成二聚体或多聚体形式。用125I标记并与胎鼠肝线粒体一起孵育时，前体与线粒体结合，约30%的标记物被导入基质空间。这种标记需要ATP的存在，并且是时间依赖性的。线粒体膜也能导入氨甲酰磷酸合成酶前体。在前体导入后，胎鼠肝线粒体中的氨甲酰磷酸合成酶活性可得到增强。
