人血红细胞酪氨酸蛋白磷酸酶（PTPP）的研究Ⅱ·胞浆PTPP的分离纯化及其主要性质  

Research for Phosphotyrosyl Protein Phosphatases (PTPPs) of Human Erythrocytes Ⅱ· Purification and Characterization of Cytosolic PTPP

作　　者：朱茂祥[1] 吴国利[1] 

机构地区：[1]北京师范大学分子生物学及生物化学研究室,军事医学科学院放射医学研究所

出　　处：《生物化学杂志》1994年第2期174-179,共6页

基　　金：国家自然科学基金

摘　　要：人血红细胞胞浆部分经（ＮＨ_４）_２ＳＯ_４沉淀，ＤＥＡＥ－纤维素（ＤＥ５２）柱层析，磷酸纤维素柱层析（Ｐ１１）得到部分纯化的ＰＴＰＰ，产率：５．７％，提纯１０７５倍。以（３２）￣Ｐ－Ｔｙｒ－Ｐｏｌｙ（Ｇ_４：Ｔ）作底物，测得其表征Ｋｍ约为０．５－０．８μｍｏｌ／Ｌ，该酶的最适ｐＨ和最适温度分别为７．０－７．８及３７－４０℃。Ｚｎ￣（２＋）等二价金属离子及Ｎａ_３ＶＯ_４等酸根基团对其活性有明显的抑制作用；ＥＤＴＡ、甘油及ＤＴＴ、巯基乙醇等则对其有强烈激活作用；而氟化物、酒石酸等对ＰＴＰＰ活性基本无影响。此外，某些蛋白质、氨基酸、核苷酸及抗肿瘤药物等对ＰＴＰＰ活性也都有不同程度的影响。特别是一些ＰＫｓ及ＰＰｓ在体外对ＰＴＰＰ活性也具有不同的作用。Through (NH_4)_2SO_4 partial precipitation, DEAE-cellulose chromatography and phospho-cellulose chromatography, PTPP can be purified partially from human erythrocytes cytosol with a 5.7% yield and a 1075-fold enrichment. Using￣(32)P-Tyr-poly(G_4:T) as substrate, the apparent Km of the enzyme is 0. 5-0. 8μmol/L, and the optimum temperature and optimum pH are 37-40℃ and 7.0-7. 4, respectively. The PTPP activities can be inhibited by bivalent cations such as Zn￣(2+) etc. and many anions(group) such as VO￣(3-)_4 etc. EDTA,glycerol, DTT, mercaptoethanol etc. can stimulate the PTPP activities; Fluoride, tartrate,some inhibitor to acidic or alkaline phosphatases, have little effect on the PTPP activities. In addition, some proteins, nucleotides, amino acids, anti-tumour agents etc. have various effects on the PTPP activities. Especially, some PKs (protein kinases) and PPs (protein phosphatases) may regulate the PTPP activities, in vitro.

关 键 词：红细胞 胞浆 蛋白质 酪氨酸磷酸酶 

分 类 号：R329.26[医药卫生—人体解剖和组织胚胎学]