Carnitine palmitoyltransferase I (CPT 1, also known as carnitine acyltransferase I) is a regulatory enzyme in mitochondrial long-chain acyl-CoA uptake and further oxidation. CPT 1 is associated with the outer mt-membrane and catalyses the formation of acylcarnitines from acyl-CoA and L-carnitine. In the next step, acyl-carnitines are transported to the mitochondrial matrix via carnitine-acylcarnitine translocase in exchange for free carnitine. In the inner side of the mtIM carnitine palmitoyltransferase 2 converts the acyl-carnitines to carnitine and acyl-CoAs. There are three enzyme isoforms: CPT 1A (liver type), CPT 1B (muscle type), CPT 1C (brain type). Isoforms have significantly different kinetic and regulatory properties. Malonyl-CoA is an endogenous inhibitor of CPT 1.
Abbreviation: CPT 1
MitoPedia topics: Enzyme