1. Figure, 21-23
Head group attachment
Membrane phospholipids:
Glycerophospholipids
sphingolipids
Backbone
Glycerol, sphingosine
Fatty acid
Hydrophilic head
Exchange head group

2. Figure, 21-24
Two strategies for forming phosphodiester bond

3. Polar head in eukaryotes
Figure, 21-26
Polar head in eukaryotes
Signal transduction

4. Figure, 21-27, 28-a
Salvage pathway in yeast
Major pathway in Eukaryotes
(yeast)
In mammals
(no CDP-diacylglycerol and serine
to PS)
Head-group exchange
(PC—PS or PE—PS)
S-adenosylmethionine
S-adenosylhomocysteine
phosphatidylserine

5. Figure, b
Phosphatidylcholine in mammals
Salvage pathway
Choline reused (strategy 2)

6. Figure, 21-29 summary of the pathways
for synthesis of major phospholipid
Mutation in ethanolamine kinase
Eliminate phosphatidylethanolamine
Synthesis: less in membrane
Transient paralysis:
electrical stimulation

7. Figure, 21-30
Ether lipid,
Plasmalogen
platelet-activating factor
Half of the heart
phospholipid

11. Head group

12. peroxisome

13. Figure, 21-31
Sphingolipids
2nd big group
Lung surfactant

14. O-
Step 1
18 C amine

15. Step 2
(SER)
Step 3
Step 4
Glycolipid
Glycosidic linkage

17. Figure, 21-32
Not required in diet
Cell membrane
Steroid hormone
Bile acids

18. Figure, 21-33
Cholesterol biosynthesis
In liver
condensation 6C 5C
polymerization
30C
cyclization

19. Figure, 21-34
Synthesis of mevalonate
cytosol
Rate-limiting step
Release 3CoA
(membrane of the SER)

20. Figure, 21-35
Mevalonate to activated isoprene
Use 3 ATP
Release 1 CO2

21. Figure, 21-36
Squalene
10C
15C
30C

22. (rose oil)

24. Figure, 21-37
Ring closure
Mixed function oxidase
plants
20 steps
Methyl group migration
and removal

25. Figure, 21-38
Cholesteryl esters
Stored or
in lipoprotein particles

26. Figure 21-39
Plasma Lipoproteins-
Lipid transport
(LDL)

27. Figure 21-39B

31. Figure21-40
Lipoprotein and
Lipid transport
apoA-I
apoB100
apoE
apoB100
apoCII--lipase

32. Figure 21-42
Uptake of cholesterol
by receptor-mediated
endocytosis

33. Figure21-40
Lipoprotein and
Lipid transport
apoA-I
SR-BI
ABC1

34. Chylomicron and VLDL remnants
Figure 21-41
Chylomicron and VLDL remnants
Surface of nascent HDL

35. Figure, 21-44
Regulation of cholesterol dp p
Inhibit
transcription

36. Figure, 21-43
SREBP (sterol regulatory element-binding protein) activation
SCAP: SREBP cleavage-activating protein—
binds to cholesterol and other sterols
HMG CoA reductase
LDLR

37. statin Figure, 21-45 Inhibitors of HMG-CoA reductase
Cholestyramine-resin binds to bile acids
-prevent reabsorption
Competitive inhibition of
HMG-CoA reductase
statin

38. Figure, isoprenoid
Prenylation
Proetins are anchored to
cellular membrane

39. Figure, 21-46
Steroid hormones from cholesterol
Increase
gluconeogenesis
And TAG cycle

40. Figure, 21-47
Side chain cleavage
Adrenal cortex
mitochondria
Hydroxylation
and cleavage

41. Fatty liver:
TAG formation and export imbalance
Extensive accumulation of TAG—cirrhosis
Free fatty acids increase in plasma, then to liver accumulation
Block production of plasma lipoproteins
a. apolipoprotein synthesis
b. lipoprotein
c. phospholipid
d. secretary pathway
Ethanol—fatty liver
Ethanol is converted to be acetaldehyde by alcohol dehydrogenase
and NADH is produced
Excess NADH inhibit CAC and increase lipogenesis (cholesterol)

42. Homework:
How insulin regulates lipid metabolism?