Correct option is C
In β-oxidation, the fatty acids are oxidized by removing a two-carbon unit at the C-2 position of the fatty acyl chain. However, the oxidation process involves several intermediate steps that begin with the β-carbon (C-3) of the fatty acid. The first oxidation step in the cycle involves the formation of a double bond between the C-2 and C-3 positions (α-β unsaturation), and subsequent reactions result in the cleavage of two-carbon units.
Information Booster:
β-oxidation involves four key steps: oxidation (creating a double bond), hydration (adding water), a second oxidation step (forming a keto group), and thiolysis (cleaving two-carbon acetyl-CoA).
The C-3 position of the fatty acid is involved in the initial oxidation step, making this position critical for the subsequent removal of a two-carbon acetyl-CoA unit.
In each round of β-oxidation, a two-carbon acetyl-CoA molecule is cleaved from the fatty acid, reducing the chain by two carbons each time.
This two-carbon unit is then utilized in the citric acid cycle (Krebs cycle) for further energy production.
Additional Information:
(a) It occurs in the intermembrane space (IMS) region of mitochondria: This is incorrect because β-oxidation occurs in the mitochondrial matrix, not the intermembrane space.
(b) All the reactions are the same for the saturated and unsaturated fatty acids: This is incorrect. Unsaturated fatty acids undergo additional steps like isomerization and reduction due to their double bonds.
(d) Lipoprotein lipase catalyzes the first step: Lipoprotein lipase hydrolyzes triglycerides into free fatty acids, but it does not directly catalyze the first step of β-oxidation.
