|
13C-labeling
|
m0
|
m1
|
m2
|
m3
|
m4
|
fragment
|
|---|
|
natural
|
1
|
0
|
0
|
0
|
0
|
C2C4
|
|
natural
|
1
|
0
|
0
|
0
|
0
|
C2C5
|
|
3-13C-Gln
|
0.008
|
0.986
|
0.0
|
0.005
|
0
|
C2C4
|
|
3-13C-Gln
|
0.005
|
0.9895
|
0.001
|
0.003
|
0.001
|
C2C5
|
|
U-13C-Gln
|
0.004
|
0.005
|
0.018
|
0.973
|
0
|
C2C4
|
|
U-13C-Gln
|
0.003
|
0.003
|
0.01
|
0.022
|
0.959
|
C2C5
|
|
n:3:U_90:2:8
|
0.889
|
0.020
|
0.002
|
0.089
|
0
|
C2C4
|
|
n:3:U_90:2:8
|
0.888
|
0.021
|
0.001
|
0.002
|
0.088
|
C2C5
|
|
n:3:U_40:30:30
|
0.437
|
0.277
|
0.006
|
0.280
|
0
|
C2C4
|
|
n:3:U_40:30:30
|
0.436
|
0.277
|
0.003
|
0.007
|
0.276
|
C2C5
|
|
n:3:U_95:2:3
|
0.940
|
0.026
|
0.001
|
0.032
|
0.0
|
C2C4
|
|
n:3:U_95:2:3
|
0.940
|
0.027
|
0.0
|
0.001
|
0.032
|
C2C5
|
- The calculated artificial labeling of naturally or artificially 13C labeled C2–C4 and C2–C5 fragments of glutamine was obtained by applying the algorithm modified to account for the isotopic effect. The samples were prepared either from unlabeled glutamine (natural), 13C- glutamine labeled at position 3 (3-13C-Gln), uniformly labeled glutamine (U-13C-Gln), or various ratios of these samples: natural : 3-13C-Gln : U-13C-Gln (n:3:U) as indicated
