Fatty Acid Biosynthesis
Transport of Acetyl-CoA
Cytosol Side
CoASH +
ATP + H 2O
Acetyl-CoA
+ ADP + P i
NADH
oxaloacetate
citrate
+
NAD
+
NADPH
+ CO 2
pyruvate
malate
Citrate lyase
Malic enzyme
Tricarboxylate
carrier
Pyruvate
carrier
oxaloacetate
citrate
CoASH
NADP
H2 O +
Acetyl-CoA
pyruvate
ADP + P i
ATP + H 2O + CO 2
Matrix Side
Formation of Malonyl-CoA
O
CoA S C CH3 + CO 2 + ATP + H2 O
• catalyzed by acetyl-CoA carboxylase
Biochemistry Handout 31.1
O
CoA S C C COOH + ADP + Pi
H2
Repeating Cycle of Fatty Acid Biosynthesis
Fatty acid
synthase
system
O
(Cys) S C CH3
Repeat
cycle
(Ser)-Pan SH
Ma-CoA
CoASH
O
(Cys) S C CH3
O
(Ser)-Pan S C C COOH
H2
CO2
(Cys) SH
O
O
(Ser)-Pan S C C C CH3
H2
NADPH + H+
NADP+
O
(Cys) S C C C CH3
H2 H2
(Ser)-Pan SH
(Cys) SH
O
OH
(Ser)-Pan S C C C CH3
H2 H
H2O
(Cys) SH
O
(Ser)-Pan S C C C CH3
H H
NADPH + H+
NADP+
(Cys) SH
O
(Ser)-Pan S C C C CH3
H2 H2
Biochemistry Handout 31.2
Transfer of acyl group
to cysteine
Lipid Biosynthesis
Preparation of Glycerol and Fatty Acids
Glycerol
glycerol + ATP glycerol-3-phosphate + ADP
or
dihydroxyacetone phosphate + NADH + H+ glycerol-3-phosphate + NAD+
Fatty Acids
fatty acid + CoASH + ATP acyl-CoA + AMP + PPi
Biochemistry Handout 31.3
Formation of Glycerol-Based Phospholipids and Triacylglycerols
H 2C OH
HO CH
O
H 2C O P OH
OH glycerol-3-phosphate
Ac-CoA
CoASH
O
H 2C O C R
HO CH O
H 2C O P OH
OH
Ac-CoA
CoASH
CTP PPi
O
O H 2C O C R
R C O CH
O
H 2C O P OH
OH
H2O
inositol
or
serine
NH2
CMP
O
O H 2C O C R
N
R C O CH
O
O
O
N
H 2C O P O P O CH2
O
OH
OH
CDP-diacylglycerol
Pi
PI
or
PS
OH OH
O
O H 2C O C R
R C O CH
H 2C OH
1,2 diacylglycerol
Ac-CoA
CoASH
O
O H 2C O C R
R C O CH
H 2C O C R
O triacylglycerol
NH2
N
O
O
O
C/E O P O P O CH2
O
OH
OH
N
CMP
CDP-C/E
PPi
CTP
OH OH
phosphoryl C or E
ADP
ATP
choline
or
ethanolamine
Biochemistry Handout 31.4
PC
or
PE