Question

Describe the β-oxidation of the fatty acid palmitate.

biochemistry

Answer 1

Beta oxidation of fatty acid palmitate can be described in the following steps:

1. Palmitate is activated first and converted to palmitoyl-CoA by the enzyme thiokinase in the cytosol.From cytosol ,it is transported through the mitochondrial membranes into the mitochondrial matrix via help of carnitine.ATP is converted to AMP+PPi in this process.
2. Palmitoyl-CoA is then converted to trans-Δ²-enoyl-CoA by the enzyme acyl-CoA dehydrogenase.This is a dehydrogenation step.FAD is converted to FADH2.FADH2 goes through ETC and gets converted to ATP molceules.
3. trans-Δ²-enoyl-CoA is then converted to -Hydroxyacyl-CoA by enzyme Enoyl-CoA hydratase.This is a hydration reaction which involves addition of water.
4. -Hydroxyacyl-CoA is converted to -Ketoacyl-CoA by enzyme  -Hydroxyacyl-CoA dehydrogenase.This is a dehydrogenation reaction.NAD+is converted to NADH+H+. NADH+ H+ goes through ETC to form ATP molecules.
5. Next , -Ketoacyl-CoA is cleaved by enzyme acyl-CoA acetyltransferase or thiolase in the presence of CoA-SH to form acetyl CoA and the thioester of palmitate with two carbons less known as myristoyl-CoA.