人脑型肌酸激酶(CK-BB)的分离和提纯

Isolation and Purification of Human Brain Creatine Kinase(CK-BB)

肌酸激酶(CK)由B及M两个亚单位组成,分子量83000～85000,包括肌酸激酶MM(CK-MM)、肌酸激酶MB(CK-MB)及肌酸激酶BB(CK-BB)三种同功酶。CK-BB的抗体能与CK-MB发生交叉反应,但不与CK-MM反应。CK-BB在血中含量甚微,难用CK-BB抗体检出。急性心肌梗塞(AMI)时血中CK-MB增多,并可用CK-BB抗体检出,有利于对AMI作出早期诊断。分离提纯CK-BB是临床应用这一技术的基础。现有的CK-BB分离提纯法,尚存在一些缺点。本文报道改良的从人脑分离提纯CK-BB的方法。

A improved method for isolation and purification of CK--BB from human brain is introduced. CK--BB of fraction IV was purified to approximately 306. 9 fold as compared with homogenate of human brain. The specific activity was 322.2 IU/mg protein. The recovery of creatine kinase activity was 52.8%. This fraction was analyzed by SDS--PAGE. It showed a single major band with an estimated molecular weight of 43000 when it stained with coomassie blue. Purity of fraction V was much better than fraction IV, but some CK activity was lost.