Birkhold S G, Sams A R
Department of Poultry Science, Texas A & M University System, College Station 77843-2472.
Comp Biochem Physiol Biochem Mol Biol. 1994 Apr;107(4):519-23. doi: 10.1016/0305-0491(94)90179-1.
A single anion-exchange column resolved two peaks of calcium-activated neutral protease activity, corresponding to the two calpain forms chicken skeletal muscle. Multiple columns have previously been needed to resolve the two isoforms from avian tissue. Calcium requirement assays confirmed one form to require approximately 100 microM Ca2+ for half-maximal activity, while the other required approximately 500 microM Ca2+. Electrophoresis revealed that the enzymes were not purified to homogeneity.
一个阴离子交换柱分离出了钙激活中性蛋白酶活性的两个峰，这两个峰对应于鸡骨骼肌中的两种钙蛋白酶形式。此前需要多个柱才能从禽类组织中分离出这两种同工型。钙需求测定证实，一种形式在钙离子浓度约为100微摩尔/升时达到最大活性的一半，而另一种则需要约500微摩尔/升的钙离子。电泳显示这些酶并未被纯化至均一状态。
