Sidorowicz W, Canizaro P C, Bĕhal F J
Am J Hematol. 1984;17(4):383-91. doi: 10.1002/ajh.2830170408.
An aminopeptidase-P has been purified 230-fold from human erythrocytes. The purified enzyme cleaved arginine from des-(Arg9)-bradykinin (Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe) had a molecular weight in nondenaturing buffers of 155,000 +/- 6,900 daltons, was not inactivated by chelating agents, had a pH optimum of 7.2, and was stimulated by manganous ions. The aminopeptidase-P was stable in intact erythrocytes for at least 21 days. Extensively washed and intact human erythrocytes cleaved arginine from exogenously supplied des-(Arg9)-bradykinin; arginine was the earliest-appearing reaction product. Purified aminopeptidase-P also cleaved a group of X-proline dipeptides including leucyl-proline, methionyl-proline, phenylalanyl-proline, arginyl-proline, and alanyl-proline. The total intra-erythrocytic aminopeptidase-P activity of the "average 70-kg man" was 2,600 units, approximately five times the amount of activity in the total lung mass. The human erythrocyte aminopeptidase-P activity was not tightly bound to the erythrocyte membrane. Intact erythrocytes also exhibited some kinin-converting enzyme activity.
一种氨肽酶 - P已从人红细胞中纯化出来，纯化倍数达230倍。纯化后的酶能从去（精氨酸9）-缓激肽（精氨酸 - 脯氨酸 - 脯氨酸 - 甘氨酸 - 苯丙氨酸 - 丝氨酸 - 脯氨酸 - 苯丙氨酸）中切割精氨酸，在非变性缓冲液中的分子量为155,000±6,900道尔顿，不被螯合剂灭活，最适pH值为7.2，且受锰离子刺激。氨肽酶 - P在完整红细胞中至少21天保持稳定。经过充分洗涤的完整人红细胞能从外源供应的去（精氨酸9）-缓激肽中切割精氨酸；精氨酸是最早出现的反应产物。纯化后的氨肽酶 - P还能切割一组X - 脯氨酸二肽，包括亮氨酰 - 脯氨酸、甲硫氨酰 - 脯氨酸、苯丙氨酰 - 脯氨酸、精氨酰 - 脯氨酸和丙氨酰 - 脯氨酸。“平均体重70千克的人”红细胞内氨肽酶 - P的总活性为2600单位，约为全肺组织活性的五倍。人红细胞氨肽酶 - P的活性并非紧密结合于红细胞膜。完整红细胞还表现出一些激肽转化酶活性。
