Calmodulin binding proteins in rat liver mitochondria.

Calmodulin binding proteins have been found in submitochondrial fractions obtained from highly purified rat liver mitochondria. The matrix fraction contains two major calmodulin binding proteins: one, having Mr of 145,000, apparently is carbamoyl-phosphate synthetase. Another has a Mr of 58,000 and has not been associated with enzyme activities. A major calmodulin binding protein of unknown function and having Mr of 32,000 has been found in the Triton X-100 solubilizate of the inner membrane. Minor amounts of two calmodulin binding proteins having Mr of about 37,000 and 56,000 have been found in the outer membrane.