Download Citric Acid Cycle (CAC)

Citric Acid Cycle (C.A.C.)
Mitochondrial Structure (cont.)
TCA
Cycle
O
Co - ASH
||
Step 1
CH3
S
CoA
O
C
O
O
O-
O-
Citrate
Synthase
O
OH
C
O-
O
C
O
O-
C
O-
Oxaloacetate
Citrate (3° Alcohol)
Step 2 & 3
O
C
O-
H2 O
C
H
OO
O
C
C
H
C
O-
O-
O-
O
O
O
C
Aconitase
O-
Citrate
C
O-
O
HO
O
O
C
HO
O-
Aconitate
C
O-
Isocitrate
(2° alcohol)
Step 4
O
O
C
C
O-
O-
O
O
C
C
O-
NAD+
O-
NADH + H+
O
O
HO
C
H
Isocitrate
C
Isocitrate
O-
O
Dehydrogenase
O-
Oxalosuccinate
CONT. NEXT SLIDE
Step 5
Classic biological redox Rx.
CO2
2° alcohol oxidized to a keto
NAD+ reduced.
O
C
O-
• Carboxylic acids that are 
to a keto group spontaneously
decarboxylate.
C
O
C
O
O-
 - keto glutarate
Step 6
O
C
O-
O
CO2
C
CoASH
O-
C
C
O
NAD+
NADH + H+
C
C
O-
O
 - keto
glutarate
 - keto
dehydrogenase
O
Succinate
Co-A
CONT. NEXT SLIDE
PGTP =
8 Kcal/m
H2O
GDP
ATP
GTP
ADP
CoASH
O
C
Step 7
OC
C
O
O-
Succinate
Succinate
Synthetase
Step 8, 9, 10
O
O
O-
H
C
H
H
C
H
O
FAD
O-
Succinate
FADH2
O
O - HOH
C
H
H
C
O
S.D.H
O-
Fumarate
Trans Dehydrogenation
O
-
NAD +
O
NAOD +
H+
HO
C
H
C
H
C
H
O
C
Fumarase
O
M.D.H
O-
O-
Malate
O.A.A
2° Alcohol
Oxidized to keto
NADH +
OO