Abstract: Calmodulin-binding proteins were purified from earthworm (Eisenia Foetida) by a procedure involving DEAE-Fast Flow, CaM-Sepharose 4B chromatographies. The purified CaM-binding proteins inhibited the activity of CaM-dependent PDE and the degree of inhibition increased with augmentation of the CaMBPs. But this inhibition could be eliminated by adding an excess of earthworm CaM. This appeared to be the typical character of CaM-binding Proteins. Three main bands of purified CaMBPs were shown on SDS-PAGE with apparent molecular weight of 62, 49 and 30kD. Their content percent was determined as 7.17%, 7.31% and 51.8% by gel scaning respectively. Three kinds of CaMBPs were detected by biotinylated CaM-overlay method. The assay of enzyme activity indicates that there was CaM-dependent Ca²⁺-ATPase activity, but no NAD kinase one.

Key words: Calmodulin-binding protein, Earthworm, Calmodulin, CaM-Sepharose 4B affinity column

摘要： 以赤子爱胜蚓(Eisenia Foetida)为材料，通过DEAE-Fast Flow离子交换层析、CaM-Sepharose亲和层析，分离纯化得到蚯蚓钙调素结合蛋白(CaMBPs)。纯化的CaMBPs对CaM激活的环核苷酸磷酸二酯酶活性有抑制作用，而且这种抑制作用可通过加入过量的CaM达到完全恢复。SDS-PAGE显示CaMBPs有3条明显主带，在EGTA存在时表现分子量分别为62, 49和30kD。紫外扫描测定含量分别为7.17%，7.31%和51.8%。用生物素-CaM覆盖法检测到3种CaM结合蛋白，与SDS-PAGE结果一致。酶活性测定实验表明在蚯蚓CaMBPs中有Ca²⁺-ATPase活性，但无NAD激酶活性。

关键词: 钙调素结合蛋白, 蚯蚓, 钙调素, CaM-Sepharose4B亲和柱