Final answer:
Omega-oxidation is a hepatic fatty acid catabolism pathway under high energy demand conditions, producing an alpha-α-keto fatty acid, followed by the creation of dicarboxylic acids and subsequent beta-oxidation at both ends, generating double acetyl-CoA units.
Step-by-step explanation:
Ω-Oxidation of Fatty Acids
Ω-oxidation, also known as omega oxidation, is a process of fatty acid catabolism that takes place predominantly in the liver. This oxidation process is particularly significant during conditions of high energy demand, such as lactation, severe diabetes, and starvation. Initially, the Ω-oxidation pathway involves the addition of a hydroxyl group to the omega (methyl) carbon of a fatty acid by hydroxylase enzymes. This hydroxyl group is further oxidized to a carboxylic acid, creating an alpha-α-keto fatty acid. What results is an α-Ω (alpha-omega) dicarboxylic acid. This compound can undergo β-oxidation at both ends of the molecule, enabling the creation of two molecules of acetyl-CoA concurrently.
Contrasting this path, traditional β-oxidation, also known as Knoop's beta oxidation of fatty acids, involves the cleavage of fatty acids at the β-carbon to form acetyl-CoA units. Each cycle of β-oxidation progressively shortens the fatty acid chain by two carbon atoms until the entire fatty acid is converted into acetyl-CoA units, which can then enter the citric acid cycle or be used in ketogenesis. The count of cycles needed and the ATP yield per fatty acid can be calculated to evaluate the energy generated from β-oxidation.