For All Medical & Non Medical Students

1. COMPOUND
LIPIDS By
N. Santhosh Kumar
Asst. Professor
Department Of Biochemistry
SIMS & RH
Tumkur

2. Phospholipids
Glycolipids
Lipoproteins

3. PHOSPHOLIPIDS
• Esters of fatty acids containing phosphate group, nitrogenous
bases and other substitution groups.
G
L
Y
C
E
R
O
L
FATTY ACID
FATTY ACID
Phosphate Nitrogenous Base

4. GLYCEROPHOSPHOLIPIDS
 Phospholipids containing alcohol as Glycerol -‘Glycero-phospholipids’.
 Hydroxyl groups at C1 & C2 of glycerol are esterified with carboxyl
groups of 2 FA.
 C3 hydroxyl group of glycerol is esterified to phosphoric acid.

5. Glycerophospholipids
Lecithin ( Phosphatidyl choline)
Cephalin ( phosphatidylethanolamine)
Phosphatidyl inositol
Phosphatidylserine
Cardiolipin (Phosphatidyl glycerol)
Plasmalogens

6. •It does not occur in the tissues.
•It is an intermediate in the synthesis of TG &
phospholipids.

7. Lecithin ( Phosphatidyl choline)
 lecithin is phosphatidic acid with Choline as the base.
 Most abundant phospholipid in
the cell membranes.
 It is distributed in animals in liver, egg yolk, brain, nerve tissue.
 Containing labile CH3 groups involved in methylation reactions.
O
O
H2C O C R
O
R C O CH
H2C O P O CH
2 CH2 N
+
CH3
CH3
CH3
O_
Phosphatidic Acid Choline

8. -Storage form of choline in body
- It play a role in nerve transmission as acetylcholine .
- Act as lipotropic factor & anti-cholesterol agent

9. Lecithin ( Phosphatidylcholine)
Dipalmitoyl lecithin Lysolecithin
 Found in lungs.
 Defect leads to Respiratory
distress syndrome in infants
-It formed by removal of the FA
either at C1 or C2 of lecithin
-Component of cobra venom & a
strong hemolysing agent.

10. lungs surfactant coats the alveolar
epithelium
Prevented collapse of the lung
reduces the surface tension within the
alveoli of the lung.
Defect in the syn of lungs
surfactant in premature infant
Collapse of the alveoli
In normal Respiratory distress
syndrome
Role of Dipalmitoyl lecithin
Decreased oxygenation of blood &
tachypnoea (rapid breathing)

11. Cephalin (phosphatidylethanolamine)
• Phosphatidic acid with ethanolamine as the nitrogenous base
• Involved in blood coagulation
• Increase the rate of thrombin formation by promoting binding of
factor –V, VIII & X
• Which catalyze the formation of thrombin from prothrombin

13. Phosphatidylinositol
• The myoinositol is attached to phosphatidic acid to form PI
• Important constituent of the cell membranes.
• Act as second messenger (diacyl glycerol & inositol triphosphate)
• Action of certain Hormones (eg: oxytocin, vasopressin) is mediated
through PI.
• It helps in the release of calcium.
O P
O
O
H2C
CH
H2C
O
C
R1
O O C
O
R2
OH
H
OH
H
H
OH
H
OH
H
O
H OH
phosphatidyl-
inositol

14. Phosphatidylserine
• Component of the cell membrane & occurs in brain & RBCs
• Plays a key role in cell cycle signaling
• Act as a signal for macrophages to engulf the cells
• Phosphatidyl threonine also present in certain tissues.

15. Phosphatidylglycerol (Cardiolipins)
• First isolated from cardiac muscle.
• It consists of 2 molecules of phosphatidic acid linked by an glycerol through
phosphate groups.
• Important component of inner mitochondrial membrane & also ETC along with
lecithin & cephalin- cellular respiration
• Antigenic properties.

16. Plasmalogens
• Found in bio-membranes in brain & muscle
• Phospholipids having α, β unsaturated FA in ether linkage with the
first OH-group of glycerol
• The second OH group is esterified to a fatty acid
• The phosphoric acid is attached to choline or ethanolamine.

17. Platelet activating factor
- C1 of glycerol -ether linked alkyl chain
- C2 is ester linked to acetic acid
- It synthesized by basophils
- stimulates platelet aggregation
- Release of serotonin from platelets,
- Involved in inflammation and allergic responses

18. 2) SPHINGO PHOSPHOLIPIDS
•If sphingosine present as alcohol -spingolipids.
Sphingomyelin:
Amide group of sphingol is
attached to carboxylic group of
fatty acid to produce –Ceramide

19. Sphingomyelin
Structural lipids of membranes of nerve tissue
Rich in Myelin sheath of nerve cell
Regulates enzyme systems- protein kinase &
protein phosphatase
Protects neural fibres of CNS

21. GLYCEROPHOSPHOLIPIDS (glycerol as alcohol)
Phosphatidyl choline lipotropic factor & lung surfactant
Phosphatidyl ethanolamine Participating in blood clotting process.
Phosphatidyl inositol (PI) second messenger & release of calcium
Phosphatidyl serine Major component of the cell membrane
Plasmalogens /
Platelet activating factor
stimulates platelet aggregation. Inflammation and
allergic reactions.
Cardiolipin Involved cellular respiration
SPINGOPHOSPHOLIPIDS (sphingosine as alcohol)
Sphingomyelin Protects neural fibres of CNS & myelin sheath
Overview of Phospholipids

22. Next PPT
CL-04 Gycolipids & lipoprotein