What is the role of carnitine shuttle?
The carnitine shuttle, a transport chain that consists of three enzymatic reactions, helps fatty acids to pass the mitochondrial membrane. They are transformed into the activated form (= acyl CoA) by the formation of a thioester linkage between the fatty acid carboxyl group and the thiol group of coenzyme A.
What is the function of carnitine shuttle in fatty acid oxidation?
The main function of carnitine is the transfer of long-chain fatty acids to mitochondria for subsequent β-oxidation . Carnitine also binds acyl residues deriving from the intermediary metabolism of amino acids and help in their elimination functioning as a scavenger .
Where does carnitine shuttle occur?
outer mitochondrial membrane
Long chain fatty acids enter the mitochondria via an acyl-carnitine shuttle where fatty acids (acyl groups) are first bound to CoA and then transferred to carnitine at the outer mitochondrial membrane.
What is carnitine carrier system?
A small molecule, carnitine, serves as a carrier across the mitochondrial membrane. This pathway requires no chemical energy supply; rather, the fact that the fatty acid in the mitochondrial matrix is being broken down by oxidation drives the process.
What is the role of L carnitine in fatty acid metabolism?
Essentially, L-carnitine transports the chains of fatty acids into the mitochondrial matrix, thus allowing the cells to break down fat and get energy from the stored fat reserves.
How is carnitine synthesized?
This molecule is either obtained from the diet or is synthesized in the body from L-lysine (bound to protein) which is methylated 3 consecutive times by an S-adenosyl-methionine.
How does fatty acyl carnitine move into the mitochondrial matrix from the intermembrane space?
The fatty acyl group is transported into the mitochondrial matrix, where it undergoes beta-oxidation. In the intermembrane space of the mitochondria, fatty acyl CoA reacts with carnitine in a reaction catalyzed by carnitine acyltransferase I (CAT-I), yielding CoA and fatty acyl carnitine.
What is carnitine shuttle and where it is present?
The carnitine shuttle represents a mechanism by which long-chain fatty acids, which are impermeable to the mitochondrial membranes, are transported into the mitochondrial matrix for the purpose β-oxidation and energy production.
Why do we need carnitine?
Carnitine plays a critical role in energy production. It transports long-chain fatty acids into the mitochondria so they can be oxidized (“burned”) to produce energy. It also transports the toxic compounds generated out of this cellular organelle to prevent their accumulation.