Purification and characterization of the heat-stable calmodulin-binding protein from the matrix of bovine heart mitochondria.

A heat-stable calmodulin binding protein was purified and characterized from the matrix of bovine heart mitochondria. It bound specifically to calmodulin in the presence of calcium, and strongly inhibited the stimulatory activity of calmodulin on phosphodiesterase. The estimated molecular weight of the calmodulin-binding protein was 61,000 dalton determined by SDS-polyacrylamide gel electrophoresis.