Amino Acid Table
Masses of Biological Molecules
Monoisotopic amino acid residue masses and immonium ion masses.
The designations of -, +, and ++ roughly indicate which immonium ions are most abundant.
In the case of lysine, the immonium ion usually loses ammonia to give an ion at 84 u.
There are a few other odd-ball amino acid fragments that have been left out of the list, but these are the main ones.
| Amino acids |
|
|
Residue mass |
Immonium ion |
| Glycine |
Gly |
G |
5 7 .02147 |
30.03438 (-) |
| Alanine |
Ala |
A |
71.03712 |
44.05003 (-) |
| Serine |
Ser |
S |
87.03203 |
60.04494 (+) |
| Proline |
Pro |
P |
97.05277 |
70.06568 {++) |
| Valine |
Val |
V |
99.06842 |
72.08133 (++) |
| Threonine |
Thr |
T |
101.04768 |
74.06059 (+) |
| Cysteine |
Cys |
C |
103.00919 |
76.0221 (-) |
| Carbamidomethylated |
|
|
160.03065 |
133.0436 (+) |
| Carboxymethylated |
|
|
161.01466 |
134.0276 (+) |
| Acrylamide adduct |
|
|
174.0643 |
147.0772 (+) |
| Isoleucine |
Ile |
I |
113.08407 |
86.09698 {++) |
| Leucine |
Leu |
L |
113.08407 |
86.09698 {++) |
| Asparagine |
Asn |
N |
114.04293 |
87.05584 (+) |
| Aspartic acid |
Asp |
D |
115.02695 |
88.03986 (+) |
| Glutamine |
Gln |
Q |
128.05858 |
101.0715 (+) |
| Lysine |
Lys |
K |
128.09497 |
101.1079 (84.08136) |
| Glutamic acid |
Glu |
E |
129.0426 |
102.0555 (+) |
| Methionine |
Met |
M |
131.04049 |
104.0534 (+) |
| Oxidized methionine |
|
|
147.0354 |
120.0483 {+) |
| Histidine |
His |
H |
137.05891 |
110.0718 {++) |
| Phenylalanine |
Phe |
F |
147.06842 |
120.0813 {++) |
| Arginine |
Arg |
R |
156.10112 |
129.114 (-) |
| Tyrosine |
Tyr |
Y |
163.06333 |
136.0762 {++) |
| Tryptophan |
Trp |
W |
186.07932 |
159.0922 (+) |
Masses of Biological Molecules
Masses of Biological Molecules
This table lists dipeptide masses (sum of residue masses + 1Da).
The values are useful for assigning internal fragment-ions and the b2 ion in tandem mass spectra
Note: C-cm; carboxy-methyl Cys | C-am; acrylamide-modified Cys | M-ox; oxidized Met
• Residues DOWN the left indicate the EXPECTED residues
• Residues ACROSS the top indicate the MUTANT residues,
Masses of Biological Molecules
This table lists the delta masses between various amino acids and can be used to help explain how an observed mass change
could represent an AA mutation.
• Residues DOWN the left indicate the EXPECTED residues.
• Residues ACROSS the top indicate the MUTANT residues.
All values are (column-row). The mass difference observed is consistent with a ROW to COLUMN mutation.