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Mass values used in FindMod : Post-translational modifications / Aminoacids / Other masses

1- Post-translational modifications (see also this page)

  abbreviation monoisotopic average UniProtKB/Swiss-Prot annotation
(controlled vocabulary)
Acetylation ACET 42.0106 42.0373 N-acetylalanine
N2-acetylarginine
N-acetylaspartate
N-acetylcysteine
N-acetylglutamate
N-acetylglycine
N6-acetyllysine
N-acetylmethionine
N-acetylproline
N-acetylserine
N-acetylthreonine
N-acetyltyrosine
N-acetylvaline
O-acetylserine
O-acetylthreonine
ADP-ribosylation ADP 541.0610 541.30 ADP-ribosylarginine
ADP-ribosylasparagine
ADP-ribosylcysteine
ADP-ribosylserine
PolyADP-ribosyl glutamic acid ‡
Allysine ALLYS -1.0316 -1.03  
Amidation AMID -0.9840 -0.9847 Alanine amide
Arginine amide
Aspartic acid 1-amide
Asparagine amide
Cysteine amide
Glutamic acid 1-amide
Glutamine amide
Glycine amide
Histidine amide
Isoleucine amide
Leucine amide
Lysine amide
Methionine amide
Phenylalanine amide
Proline amide
Serine amide
Threonine amide
Tryptophan amide
Tyrosine amide
Valine amide
S-archaeol ARCH 634.6628 635.14 S-archaeol cysteine
Beta-methylthiolation BMTH 45.9877118 46.08688 3-methylthioaspartic acid
Biotin BIOT 226.0776 226.2934  
Bromination BROM 77.9105 78.9 Bromohistidine
6'-bromotryptophan
N6-1-carboxyethyl lysine CETH 72.0211 72.06  
Cholesterol CHOL 368.3443 368.64 Cholesterol glycine ester
Cis-14-hydroxy-10,13-dioxo-7-heptadecenoic
acid aspartate ester		 CHDH 294.1831 294.39  
Citrullination CITR 0.9840276 0.98476 Citrulline
C-Mannosylation CMAN 162.052823 162.1424  
Cysteine sulfenic acid (-SOH) CSEA 15.9949146 15.9994  
Cysteine sulfinic acid (-SO2H) CSIA 31.9898292 31.9988  
Cysteine persulfide CYSP 31.9721 32.06  
Deamidation DEAM 0.9840 0.9847 Deamidated asparagine
Deamidated glutamine
Deamidation followed by a methylation DEAME 14.9997 15.01 Glutamate methyl ester (Gln)
n-Decanoate DECA 241.1678 241.33 O-decanoyl serine
O-decanoyl threonine
2,3-didehydroalanine (Ser) DHAS -18.0106 -18.02  
2,3-didehydrobutyrine DHB -18.0106 -18.02  
(Z)-2,3-didehydrotyrosine DHY -2.0156 -2.02  
S-diacylglycerol cysteine DIAC 576.5117¹ 576.94¹ S-diacylglycerol cysteine
Dihydroxylation DIHYDR 31.9898 32.00 3,4-dihydroxyarginine
3,4-dihydroxyproline
4,5-dihydroxylysine
Dimethylation DIMETH 28.0314 28.0538 Asymmetric dimethylarginine
N4,N4-dimethylasparagine
N6,N6-dimethyllysine
Omega-N-methylated arginine†
Symmetric dimethylarginine
Dimethylation of proline DIMETP 29.0391 29.06 N,N-dimethylproline
Diphthamide DIPH 143.1184 143.21  
FAD FAD 783.1415 783.542 O-8alpha-FAD tyrosine
Pros-8alpha-FAD histidine
S-8alpha-FAD cysteine
Tele-8alpha-FAD histidine
S-farnesyl cysteine FARN 204.1878 204.3556  
S-12-hydroxyfarnesyl cysteine FAR0 220.1827 220.35  
3-phenyllactic acid FLAC 0.9840 0.98  
FMN conjugation (Cys) FMNC 456.1046 456.34 S-4a-FMN cysteine
S-6-FMN cysteine
FMN conjugation (Ser/Thr) FMN 438.0940 438.33 FMN phosphoryl serine
FMN phosphoryl threonine
FMN conjugation (His) FMNH 454.0889 454.33 Tele-8alpha-FMN histidine
Formylation FORM 27.9949 28.0104 N-formylmethionine
N-formylglycine
N6-formyllysine
Geranyl-geranylation GERA 272.2504 272.4741 S-geranylgeranyl cysteine
Gamma-carboxyglutamic acid GGLU 43.98983 44.0098 4-carboxyglutamate
O-GlcNAc GLCN 203.0794 203.1950  
Glucosylation (Glycation) GLUC 162.0528 162.1424  
Glutathionylation GLUT 305.0680814 305.3056 glutathione
Hydroxylation HYDR 15.9949 15.9994 3',4'-dihydroxyphenylalanine (DOPA)
3-hydroxyasparagine
3-hydroxyaspartate
3-hydroxyproline
3-hydroxytryptophan
4-hydroxyarginine
4-hydroxyproline
5-hydroxylysine
D-4-hydroxyvaline
Hydroxyproline
Hypusine HYPU 87.0684 87.12  
Lipoyl LIPY 188.033 188.3027  
Methylation METH 14.0157 14.0269 5-methylarginine
2-methylglutamine
Cysteine methyl ester
Glutamate methyl ester (Glu)
Leucine methyl ester
Lysine methyl ester
Methylhistidine
N-methylalanine
N-methylisoleucine
N-methylleucine
N-methylmethionine
N-methylphenylalanine
N-methylproline
N-methyltyrosine
N4-methylasparagine
N5-methylarginine
N5-methylglutamine
N6-methyllysine
Omega-N-methylarginine
Pros-methylhistidine
S-methylcysteine
Tele-methylhistidine
Methionine sulfone MSONE 32.00 31.9898  
Myristoylation MYRI 210.1984 210.3598 N-myristoyl glycine
N(6)-myristoyl lysine
S-myristoyl cysteine
S-Nitrosylation NTRY 28.99017 28.99816 S-nitrosocysteine
n-Octanoate OCTA 126.1044 126.1986 O-octanoyl serine
O-octanoyl threonine
Omega-hydroxyceramide glutamate ester OHC 760.7308² 761.3²  
3-oxoalanine (Cys) OXOAC -17.9928 -18.08  
3-oxoalanine (Ser) OXOAS -2.0156 -2.02  
2-oxobutanoic acid OXOB -17.0265 -17.03  
Palmitoylation PALM 238.2297 238.4136 N-palmitoyl cysteine
N(6)-palmitoyl lysine
O-palmitoyl serine
O-palmitoyl threonine
S-palmitoyl cysteine
S-palmitoleyl cysteine PALE 236.2140 236.39  
Phosphatidylethanolamine amidated glycine PE 699.5203³ 699.98³  
Phosphorylation PHOS 79.9663 79.9799 4-aspartylphosphate
Phosphoarginine
Phosphocysteine
Phosphohistidine
Phosphoserine
Phosphothreonine
Phosphotyrosine
Pros-phosphohistidine
Tele-phosphohistidine
Pyridoxal phosphate PLP 229.014 229.129  
N6-poly(methylaminopropyl)lysine POLYM 426.4410 426.73  
Phosphopantetheine PPAN 339.078 339.3234  
Pyrrolidone carboxylic acid (Glu) PYRE -18.0106 -18.02  
Pyrrolysine PYRK 109.0528 109.13  
Pyrrolidone carboxylic acid PYRR -17.0266 -17.0306  
Pyruvic acid (Cys) PYRUC -33.0037 -33.10  
Pyruvic acid (Ser) PYRUS -17.0265 -17.03  
Sulfation SULF 79.9568 80.0642 Sulfoserine
Sulfothreonine
Sulfotyrosine
1-thioglycine THIOG 15.9772 16.06  
Thyroxine THRX 595.6123 595.68  
2',4',5'-topaquinone TOPA 29.9742 29.98  
Triiodothyronine THRN 469.7158 469.78  
Trimethylation TRIMETH 43.0548 43.09 N6-methylated lysine†
N6,N6,N6-trimethyllysine
N,N,N-trimethylalanine
N6,N6,N6-trimethyl-5-hydroxylysine TRIMETK 59.0497 59.09  

(¹) Representative structure (palmitate- and oleate-substituted glycerol).
(²) Representative structure (triacontanoate-substituted icosasphingosine).
(³) Representative structure (palmitate- and oleate-substituted glycerol bound to phosphoethanolamine).
(‡) Polymer of ribosylglutamic acid.
(†) Ambiguous description used in the cases where the exact methylation type has not been characterized yet.

2- Amino acids

monoisotopic average
Alanine (A) 71.03711 71.0788
Arginine (R) 156.10111 156.1875
Asparagine (N) 114.04293 114.1038
Aspartic acid (D) 115.02694 115.0886
Cysteine (C) 103.00919 103.1388
Glutamic acid (E) 129.04259 129.1155
Glutamine (Q) 128.05858 128.1307
Glycine (G) 57.02146 57.0519
Histidine (H) 137.05891 137.1411
Isoleucine (I) 113.08406 113.1594
Leucine (L) 113.08406 113.1594
Lysine (K) 128.09496 128.1741
Methionine (M) 131.04049 131.1926
Phenylalanine (F) 147.06841 147.1766
Proline (P) 97.05276 97.1167
Serine (S) 87.03203 87.0782
Threonine (T) 101.04768 101.1051
Tryptophan (W) 186.07931 186.2132
Tyrosine (Y) 163.06333 163.1760
Valine (V) 99.06841 99.1326
Non-standard amino acids
Selenocysteine (U) 150.953636 150.0388
Pyrrolysine (O) 237.147727 237.3018

3- Mass differences due to amino acid substitutions: using average / monoisotopic mass values.

4- Other mass values

monoisotopic average
Alkylation 14.01564 14.02688
Carbamylation 43.00581 43.02502
Carboxymethyl cysteine (Cys_CM) 161.01466 161.1755
Carboxyamidomethyl cysteine (Cys_CAM) 160.03065 160.1908
Pyridyl-ethyl cysteine (Cys_PE) 208.067039 208.284
Propionamide cysteine (Cys_PAM) 174.04631 174.2176
Methionine sulfoxide (MSO) 147.0354 147.1920
Homoserine Lactone (HSL) 100.03985 100.09714
H 1.00783 1.00794
H+ 1.00728 1.00739
O 15.9949146 15.9994
H2O 18.01056 18.01524
Last modified 14/Feb/2006 by ELG

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