Page 186 - Color Atlas of Biochemistry

Protein Metabolism 177

A. Proteolytic enzymes

COO C-Terminus
Serine proteinase
H 3 N N-Terminus 3.4.21.n
Aminopeptidase Cysteine proteinase H 3 N COO
2
[Zn ] 3.4.11.n Exopeptidase 3.4.22.n
Endopeptidase Aspartate proteinase
3.4.23.n
Metalloproteinase Dipeptidase
H 3 N 3.4.24.n [Zn ] 3.4.13.n
2

Carboxy-
peptidase
Amino acid residue 3.4.17.n
COO

B. Proteasome C. Serine proteases

Folded Activated Disulfide Autocatalytic
protein ubiquitin bond cleavage
Auto-
cata-
lytic
cleavage
Marking Activation
with of
ubiquitin ubiquitin
Ubiquitinated
protein
Cleavage
by entero-
peptidase Active
19 S and trypsin center
particle
1 Enteropeptidase 2 Trypsin
Binding
3.4.21.9 3.4.21.4
20 S
nucleus 1. Trypsinogen activation

19 S
particle
Asp-102

Ser-195
Lysine residue

A

His-57
Unfolding Degradation
Substrate
A
2. Trypsin: active center

Koolman, Color Atlas of Biochemistry, 2nd edition © 2005 Thieme
All rights reserved. Usage subject to terms and conditions of license.