LipidMetabolismI
Dr.KevinAhern
Fat and Glycerophospholipid Synthesis
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Phosphatidic Acid
Glycerol-3-P
Fat (Triacylglycerol)
Glycerophospholipids
Fat Breakdown
Signaling
Catalysis
Glycero PhosphoLipid
Glycerophospholipids / Phosphatides
• Glycerophospholipic Synthesis Involves CDP-Activated Intermediate
• Two General Mechanisms
Phosphatidic Acid + CTP + PPi
CDP-Diacylglycerol
Phosphatidyl Portion of Final Product
Will Split Off as CMP
CDP-Diacylglycerol + Inositol
+
Phosphatidylinositol + CMP
• Second Mechanism - Activate Add-on Molecule
ATP ATP CTP PPi
Ethanolamine Phosphorylethanolamine CDP-Ethanolamine
Splits OffAdds to Diacylglycerol
CDP-Ethanolamine + CMP + Diacylglycerol Phosphatidylethanolamine
Sphingolipid Biosynthesis
SphingolipidsBranch Point
Amino Acid
Fatty Acid
Ceramide Synthesis
Sphingolipid Synthesis
MembraneLipidMetabolism• Sphingolipids
PhosphocholineR = OR
PhosphoethanolamineR =
Single SugarR =
Complex SugarR =
Sphingomyelin
Cerebroside
Ganglioside
Sphingolipid Breakdown Diseases
Cholesterol Biosynthesis
Acetyl Group
Cholesterol
Branch Point
Cholesterol Biosynthesis
IPP + DPP
IPP DMAPP
Geranyl-PP
Lanosterol
Acetyl-CoA
Farnesyl-PP
IPP
Squalene2
5 Carbons Each
10 Carbons
15 Carbons
30 Carbons
30 Carbons
Lanosterol Cholesterol
19 Steps
Cholesterol Metabolism
Cholesterol Bile AcidsExcretion
Mineralocorticoids &
Corticosteroids
Cholesterol Metabolism
Lipid Movement From the Diet
Removal of 2 Fatty Acids
Reattachment of 2 Fatty Acids
Inside IntestineOutside Intestine
Apolipoprotein Complexes
Receptor-mediated Endocytosis
Foam Cell Aggregate
Carotid Artery Plaque