Page 202 - Color Atlas of Biochemistry

Porphyrin Metabolism 193

A. Heme biosynthesis

2 Tricarboxylic
acid cycle R 2 R 1
Succinyl COO
CoA R 1 A B R 2
CH N N
2
Heme Fe 2+
CH
2 N N
2+ D C
S C O R 1 R 1
A
2
R 3 R 3 Vinyl
H C COO Glycine residue
2
NH 3
R
Fe 2 8 COO
1
S CH 2 CH 2
2 A Protoporphyrin IX
CH 3 CH CH 2
2 CO 2
6[H] 7 R 1 R 2 R 3

1 COO Protoporphyrinogen IX
1 COO CH
2
2 5-Amino- 2 CO
CH 2 CH 2 levulinate 2 6 Mitochondrion
(ALA)
CH 2 O C O 2
5
H C C 5 CH 2
2
O
NH 3 NH 3 Cytoplasm

Coproporphyrinogen III
COO COO
CH 2 CH 2
CH 3 CH 2 CH 2
4 CO 5
2 2
R 1 R 2 R 3
2 H O
2
COO
OOC CH 2 R 2 R 1 COO COO
R 1
CH CH A B R 2 COO CH CH
Pyrrole 2 2 NH HN 2 2
ring C C 3 4 CH 2 CH 2 CH 2
NH HN
H C C CH D C
2
N R 1 R 1 R 1 R 2 R 3
NH 3 H 4 NH 4 H O
2
R 3 R 3
Porphobilinogen Uroporphyrinogen III

1 5-Aminolevulinate synthase 2 Porphobilinogen synthase 3 Hydroxymethylbilane synthase
[PLP] 2.3.1.37 4.2.1.24 4.3.1.8
4 Uroporphyrinogen-III synthase
4.2.1.75

Koolman, Color Atlas of Biochemistry, 2nd edition © 2005 Thieme
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