How is malonyl-CoA synthesized?
Table of Contents
How is malonyl-CoA synthesized?
Malonyl-CoA is formed by carboxylating acetyl-CoA using the enzyme acetyl-CoA carboxylase. One molecule of acetyl-CoA joins with a molecule of bicarbonate, requiring energy rendered from ATP. Malonyl-CoA is utilised in fatty acid biosynthesis by the enzyme malonyl coenzyme A:acyl carrier protein transacylase (MCAT).
How does acetyl-CoA transfer from mitochondria to cytoplasm for fatty acid synthesis?
Acetyl-CoA is moved through the mitochondrial membrane, and enters the cytoplasm of the cell, as the molecule citrate. In the cytoplasm, these citrate molecules are once again converted back to acetyl-CoA. This reaction requires that the cell use up some energy by breaking down an ATP molecule.
How is acetyl-CoA transported out of mitochondria into the cytosol?
Citrate synthesized from oxaloacetate and acetyl-CoA is transported from mitochondria to the cytosol via the tricarboxylate anion carrier system and cleaved to yield acetyl-CoA and oxaloacetate. Figure 16.8. Cytoplasmic generation of acetyl-CoA via citrate transport and related reactions.
How is acetyl-CoA transported from the mitochondrial matrix?
Fatty acid biosynthesis occurs in the cytosol, so acetyl CoA has to be transported to the cytosol from mitochondria. As it can not cross the membrane, it is transported out of mitochondria as citrate. Citrate is formed by the condensation of acetyl CoA with oxaloacetate by the enzyme citrate synthase.
Which process transport the acetyl-CoA to mitochondria?
Cytoplasmic fatty acyl CoA is converted to fatty acyl carnitine by carnitine acyl transferase (CAT I), an enzyme of the inner leaflet of the outer mitochondrial membrane. Fatty acyl carnitine is then trransported by an antiport in exchange for free carnitine to the inner surface of the inner mitochondrial membrane.
Where does acetyl-CoA formation occur in the mitochondria?
Acetyl CoA formation occurs in the mitochondrial matrix through a process called beta-oxidation. Beta-oxidation is the breakdown of fatty acids to produce acetyl CoA. The mitochondrion is an organelle, and organelles are structures that perform specific jobs within the cell.
How is acetyl CoA transported out of mitochondria?
Fatty acid biosynthesis occurs in the cytosol, so acetyl CoA has to be transported to the cytosol from mitochondria. As it can not cross the membrane, it is transported out of mitochondria as citrate.
