Chemistry Reference
In-Depth Information
O
O
COOH
N
N
O
N
α
HO
•
O
2
COOH
+
O
β
γ
O
O
O
2
•
•
O
H
2
O
N
O
O
OH
OH
O
OH
O
CH
2
O
O
O
O
N
N
N
N
O
CH
3
O
O
O
O
OH
O
H
O
OH
O
OH
O
O
NH
2
+14 Da
(Minor product)
+16 Da
(Minor product)
-30 Da
(Major product)
+
O
CH
3
(Side-chain modification)
(Backbone cleavage)
Figure 4.22.
Oxidation of glu by the radical transfer from the γ-carbon at the side
chains of the protein (adapted from xu and chance [261] with the permission of the
American chemical Society).
OH
HO
4
3
NHR
′
NHR
′
NHR
′
NHR
′
NHR
′
HO˙/O
2
/HOO·
5
O
HO
+
+
+
N
N
O
O
N
N
N
O
O
O
R
O
R
O
R
O
R
O
R
O
(Pyroglutamic acid)
+ 14 Da
(3-Hydroxyproline)
+ 16 Da
(4-Hydroxyproline)
+ 16 Da
(5-Hydroxyproline)
+ 16 Da
HO˙/O
2
/HOO·
H
2
N-R
′
+ CO
2
+
NHR
′
NHR
′
HOOC
NH
NHR
′
O
O
HOOC
H
2
N
N
HN
O
O
O
R
O
(Glutamyl)
+
R-COOH
R
O
R
O
(2-Pyrrolidone)
(Glutamic acid)
+ 32 Da
(Glutamyl semialdehyde)
R-COOH + NH
2
-(CH
2
)
3
-COOH
(
γ
-Amino butyric acid)
(R, R
′
= N- and C-terminal sides of protein molecule)
(Backbone cleavage)
(Side-chain modification)
Figure 4.23.
Modification of Pro (adapted from xu and chance [261] with the permis-
sion of the American chemical Society).
Search WWH ::
Custom Search