Identification of two distinct protein carboxyl methyltransferases in eucaryotic cells.

Two distinct protein carboxyl methyltransferases (PCM) were identified in the electric organ of Torpedo ocellata. They were separated from each other in the active form by means of nondenaturing gel electrophoresis and by p-(chloromercuri)benzoate-agarose chromatography, and were individually identified by specific polyclonal antibodies. The existence of at least two distinct PCMs in eucaryotic cells raises the possibility that these enzymes are involved in distinct transmethylation reactions.