一种新型蚯蚓脱氧核糖核酸酶酶学性质的研究  

Characteristics of a novel deoxyribonuclease from earthworm Eisenia foetida

作　　者：王晓媛[1] 姚建强[1] 康慧芳[1] 樊慧杰[1] 杨利军[2] 牛勃[1] 

机构地区：[1]山西医科大学生物化学与分子生物学教研室,山西太原030001 [2]山西医科大学科技处,山西太原030001

出　　处：《中国生化药物杂志》2008年第1期12-15,共4页Chinese Journal of Biochemical Pharmaceutics

基　　金：国家自然科学基金(30472251);山西省青年科技研究基金(20051044)

摘　　要：目的研究蚯蚓组织中1种新型脱氧核糖核酸酶(EWD1)的主要酶学性质。方法用SDS-PAGE凝胶电泳、质谱分析、毛细管等点聚焦电泳法和酶活性测定等方法。结果EWD1的相对分子质量约为157000。Mn2+、Ca2+是该酶的抑制剂,Mg2+对酶的活性基本上没有影响。该酶的最适温度为37℃,最适pH值为5.2,等电点为6.12。以小牛胸腺DNA为底物,测得Km为1.58 mg/mL,Vmax为5.36 mg/(mL.min)。结论蚯蚓组织中发现的此种脱氧核糖核酸酶EWD1具有特殊的酶学性质,明显区别于已知的脱氧核糖核酸酶类。Purpose To study the major characteristics of a novel deoxyribonuclease （EWD1）from Earthworm Eisenia foetida. Methods SDS-PAGE gel electrophoresis, mass spectrometry （MALDI-TOF MS）, capillary electrophoresis isoelectric focusing （CE-IEF） and enzyme activity assays were used for the study. Results The molecular mass of EWD1 was about 157 000. Mn^2＋ and Ca^2＋ were inhibitors for EWD1, and Mg^2＋ had no effect on the enzyme activity. The optimum temperature was 37 ℃, and the optimum pH was 5.2. The Km and Vmax values of the purified enzyme were calculated as 1.58 mg/mL and 5.36 mg/（mL·min）, respectively, with calf thymus DNA as substrates at the optimum pH. Conclusion EWD1 extracted from Earth- worm Eisenia foetida has special characteristics which are different from those of the present DNase.

关 键 词：蚯蚓 脱氧核糖核酸酶 酶学性质 

分 类 号：Q55[生物学—生物化学]