BMS1011: Lipid Synthesis and Oxidation

What is the primary function of the triacylglycerol cycle?

Which of the following lipoproteins is responsible for transporting cholesterol from the liver to tissues?

What is the composition of lipoproteins?

What is the primary function of LDL?

What is the precursor molecule for cholesterol synthesis?

Which of the following lipoproteins is responsible for transporting cholesterol from the intestines to the liver?

What is the primary function of HDL?

What is the composition of triacylglycerols?

What is the primary function of the triacylglycerol cycle in relation to cholesterol synthesis?

Which of the following is a characteristic of lipoproteins?

Fatty Acid Synthesis

Fatty acid synthesis begins with the formation of malonyl-CoA from acetyl-CoA, CO2, and ATP
The process is catalyzed by the fatty acid synthase enzyme and occurs in the cytosol
Elongation of fatty acid chain involves condensation, reduction, dehydration, and reduction reactions
The overall synthesis of palmitate (16C fatty acid) requires 7 acetyl-CoA, 7 CO2, 7 ATP, and 14 NADPH
The process involves the transfer of acetyl-CoA and malonyl-CoA, and the reduction of β-keto group using NADPH
Sources of NADPH include malic enzyme and the pentose phosphate pathway
Fatty acid synthesis is regulated and distinct from fatty acid breakdown, requiring acetyl-CoA, NADPH, and malonyl-CoA as key precursors

Triacylglycerol Synthesis

Triacylglycerol synthesis involves the formation of triacylglycerol from fatty acids and glycerol
Synthesis and degradation of triacylglycerol are tightly regulated
The triacylglycerol cycle helps to re-synthesize triacylglycerols

Cholesterol Synthesis

Cholesterol synthesis involves the synthesis of cholesterol from acetyl-CoA
Cholesterol is transported in the blood as lipoproteins
Chylomicrons transport cholesterol and triacylglycerol from the intestines to the liver
VLDL transports cholesterol and triacylglycerol from the liver to tissues
LDL delivers cholesterol to tissues
HDL removes cholesterol from peripheral tissues

Understand the significance of lipogenesis and compare lipid oxidation with reductive biosynthesis in this topic on lipid synthesis, triglycerides, and cholesterol.