Cholesterol ester formation involves esterification of cholesterol with which substance?

Cholesterol ester formation involves esterification of cholesterol with which substance?

• A. Protein
• B. Triglyceride
• C. Fatty acid
• D. Digitonin

Answer: (C)

Cholesterol ester formation relies on attaching a fatty acid to cholesterol to create a cholesteryl ester. The hydroxyl group on cholesterol is esterified by a fatty acyl group, typically donated as fatty acyl-CoA (with ACAT enzyme) or transferred from phosphatidylcholine in plasma (with LCAT). This creates a stable, highly hydrophobic cholesterol ester that can be packed into lipoproteins for transport and storage. The other options don’t provide the fatty acid needed to form the ester bond: proteins aren’t the acyl donor, triglycerides involve a glycerol backbone with fatty acids rather than cholesterol, and digitonin is just a detergent, not part of this esterification process.

Cholesterol ester formation relies on attaching a fatty acid to cholesterol to create a cholesteryl ester. The hydroxyl group on cholesterol is esterified by a fatty acyl group, typically donated as fatty acyl-CoA (with ACAT enzyme) or transferred from phosphatidylcholine in plasma (with LCAT). This creates a stable, highly hydrophobic cholesterol ester that can be packed into lipoproteins for transport and storage. The other options don’t provide the fatty acid needed to form the ester bond: proteins aren’t the acyl donor, triglycerides involve a glycerol backbone with fatty acids rather than cholesterol, and digitonin is just a detergent, not part of this esterification process.