Purification, characterization and partial amino acid sequences of carnitine palmitoyl-transferase from human liver

Carnitine palmitoyl-transferase has been extracted with 0.5% Tween-20 from human liver homogenate and purified to homogeneity. The purified enzyme has a native Mr of 274 kDa. The subunit Mr is of 66 kDa, as shown by SDS-PAGE and immunoblots obtained with antibodies raised against human CPT. Purified CPT shows high affinity for palmitoyl-CoA and palmitoyl-carnitine and is not inhibited by malonyl-CoA. Seven tryptic peptides and the N-terminal of purified human CPT have been sequenced, and found homologous to rat CPT sequence. Both antibodies and peptide sequences are important tools for the investigation of the molecular basis of CPT deficiency in man.