ACID–BASE PROPERTIES - Oxidation of Amino Acids, Peptides, and Proteins: Kinetics and Mechanism - page 57

TABLE 2.1. ( Continued )

Type of
Side
Chain

Abbreviated
Name (One
Letter) Name Structure of the Side Chain p K a1 p K a2 p K a3

Phenylalanine Phe (F)

2.28 f 9.34 f

-

CH 2

Proline j

Pro (P)

k

10.6 l

-

O

H
N

C

OH

a From Fiol et al. [43].
b From Fiol et al. [44].
c From Bastug et al. [74] at I = 0.10 M (NaClO 4 ).
d From Martell and Smith [42].
e From Demirelli and Köseoĝlu [45].
f From Nagai et al. [32].
g From Martell and Smith [42] at I = 0.1 M.
h From Sharma et al. [39].
i From Sharma et al. [41].
j This is drawn in full.
k From Martell and Smith [42].
l From Fazary et al. [3].

TABLE 2.2. Dissociation Constants of Cystine, Glutathione (Reduced and
Oxidized) at Zero Ionic Strength at 25°C

Glutathione
(Reduced) b

Glutathione
(Oxidized) c Cystine a Diglycine d Triglycine e

p K a1 1.36 2.14 1.22 3.06 3.26

p K a2 1.61 3.71 2.12 8.1 7.9

8.64 9.08 3.28 - -

p K a3

p K a4 9.41 10.13 4.21 - -

p K a5 - - 9.45 - -

p K a6 - - 10.49 - -

a From Furia et al. [28].
b From Crea et al. [37].
c From Crea et al. [38].
d From Armesto et al. [124].
e From Simic et al. [125].