Abstract: Both Calmodulin(CaM) and a Neo-Calcium Binding Protein(NCBP) were separated and purified from earthworm(Eisenia foetida) by phenyl-sepharose CL-4B hydrophobic chromatography and DEAE-F.F.ion exchange chromatography. Two proteins were shown to be homogeneous by SDS-PAGE, PAGE, and IEF. Molecular weight and pI of CaM and NCBP are 18.9 kD and 16kD, 3.6 and 4.3 respectively. Their peptide map is different. Both of thier N-terminus are Gly. C-terminus of CaM is Met. The electrophoretic mobility of earthworm CaM and NCBP effected by Ca²⁺ is similarly as that of the bovine brain CaM. Earthworm CaM can activate bovine heart cyclic nucleotide phosphodiesterase, NCBP has similar properties too. The Phe/Tyrratio is 8∶1, while that of NCBP is 7∶2. We can observe thier characterstic UV absorption peaks. A Comparison between the properties of earthworm CaM and NCBP indicates that they are similar to each other.

Key words: Calmodulin, Neo-Calcium binding protein, Earthworm, Cyclic nucleotide phosphodiesterase

摘要： 以赤子爱胜蚓(Eisenia Foetida)为材料分离纯化了钙调素(Calmodulin, CaM)，并得到一种新的钙结合蛋白(Neo-Calcium Binding Protein, NCBP)经SDS-PAGE、PAGE 和等电聚焦电泳鉴定，这两种蛋白均表现均一。CaM分子量为18.9kD，NCBP为16kD, 等电点分别为3.6和4.3，两种蛋白具有不同的肽谱。研究证明蚯蚓CaM具有与其他来源 CaM所特有的性质，对环核苷酸磷酸二酯酶有明显的激活作用，电泳行为受Ca^2＋的影响出现CaM特征性电泳行为，NCBP亦有类似性质。CaM和NCBP N_-端均为Gly，CaM C_-末端为 Met。经氨基酸组成分析表明蚯蚓CaM及NCBP和其他动物CaM一样，不含Cys和Trp。其中Phe/Tyr比分别为8∶1和7∶2。可观察到它们的特征性紫外吸收光谱。

关键词: 钙调素, 新钙结合蛋白, 蚯蚓, 环核苷酸磷酸二酯酶