CarnitinPalmitoyltransferase

Carnitine palmitoyltransferase, often abbreviated as CPT, refers to a group of enzymes crucial for cellular energy metabolism. These enzymes are primarily involved in the transport of long-chain fatty acids from the cytoplasm into the mitochondrial matrix. This process is essential for beta-oxidation, the breakdown of fatty acids to produce adenosine triphosphate (ATP), the main energy currency of the cell.

There are two main isoforms of carnitine palmitoyltransferase: CPT1 and CPT2. CPT1 is located on the outer mitochondrial membrane and catalyzes the first committed step in fatty acid oxidation by attaching a carnitine molecule to the fatty acyl-CoA, forming a fatty acyl-carnitine. This intermediate can then be transported across the inner mitochondrial membrane. CPT2 resides on the inner mitochondrial membrane and reverses this reaction, converting the fatty acyl-carnitine back into fatty acyl-CoA and free carnitine, allowing the fatty acyl-CoA to enter the mitochondrial matrix for beta-oxidation.

Deficiencies in CPT enzymes can lead to various metabolic disorders, collectively known as carnitine palmitoyltransferase deficiency. These conditions impair the body's ability to utilize fatty acids for energy, particularly during periods of fasting or increased energy demand. Symptoms can range from muscle weakness and pain to more severe neurological and cardiac issues. Diagnosis often involves biochemical testing of blood and urine, and management typically focuses on dietary interventions and avoiding prolonged fasting.