小牛胸腺末端脱氧核苷酰转移酶的分离纯化

Isolation of terminal deoxynucleotidyltransferase(TdT) from calf thymus

目的：利用蛋白质分离纯化技术提取末端脱氧核苷酰转移酶（ＴｄＴ），以研究其分子组成、理化性质，探讨其与白血病之间的联系。方法：用匀浆、ＤＥＡＥ纤维素柱层析、磷酸纤维素柱层析、（ＮＨ４）２ＳＯ４分段盐析、Ｓｅｐｈａｄｅｘ柱层析、羟磷灰石柱层析等方法，从小牛胸腺中分离纯化ＴｄＴ。每步均留样，测蛋白质含量和酶活力。结果：经一系列分离步骤，纯化ＴｄＴ，酶的活力增加２６．４倍，并发现在羟磷灰石柱层析的穿过峰部分，存在一个对ＴｄＴ有抑制作用的组份。结论：本研究成功地纯化ＴｄＴ，为进一步研究其理化性质及其临床应用奠定基础。

Objective:Isolation of terminal deoxynucleotidyltransferase(TdT) for studying its molecular constitute,physical and chemical properties,and its relation to leukemia.Methods:Homogenation,DEAE cellulose column chromatography,(NH 4) 2SO 4 fractional salting out,Sephadex column chromatography and hydroxyapatite(HA) column chromatography were used to isolate TdT from calf thymus.The samples from every step were measured for content of the protein and the activity of the enzyme.Results:After a series of purification steps,the specific activity of TdT increased 26.4 times.An inhibition component of TdT was found in the elution fluid of HA column chromatography.Conclusions:Purification of TdT was succeeded for further studying its physical and chemical properties and its clinical application.