Biochemistry: Most Important Steps in Beta Oxidation of FA.

Lipid Metabolism

Knoop 1904 was the first scientist to discover β-oxidation.
The carbon that is attached to the carboxylic group is known as α-carbon, the carbon next to it is known as β- carbon (3^rd carbon including the COOH group). Oxidation of fatty acids occurs at the β-carbon. That is why it is known as β- oxidation. The last carbon is known as omega carbon.
When fats are hydrolyzed by lipases, we get glycerol plus fatty acids.
Glycerol comes to the liver where by enzyme glycerol kinase it will form glycerol-3-PO₄, which can be dehydrogenated by Glycerol -3- PO₄ dehydrogenase to DHAP- intermediate of glycolysis can be used for energy purpose or for gluconeogenesis by reversal of glycolysis. Secondly the Glycerol-3 PO₄ can go in the adipose tissue.
For the synthesis of fat glycerol must be in Glycerol -3- PO₄ form. Adipose tissue does not contain glycerol kinase so they are dependent on liver for the supply of Glycerol -3- PO₄.
Fatty acids are known as free fatty acids or NEFA. These FFA are bound to albumin in plasma for transport and in the cells to FA binding protein (never free).
Beta oxidation takes place in mitochondria while FFA are present in cytosol. These FA have to be transferred into the mitochondria for oxidation.

Activation
Oxidation – removal of Hydrogen or addition of oxygen (FAD dependent dehydrogenation)
Hydration
2^nd oxidation (NAD dependent)
Cleavage

FOR COMPLETE LECTURE PLEASE VISIT THE COURSE PAGE IN BIOCHEMISTRY II SECTION. CLICK THE CURRICULUM TAB TO VIEW FULL LIST IN METABOLISM OF LIPIDS.