Delta Mass
A Database of Protein Post Translational Modifications
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Avg.Mass
Change
Modification
-79 5' dephospho
-58 Desmosine (from Lysine)
-48 decomposed carboxymethylated Methionine
-44 decarboxylation of gamma carboxy Glutamate
-43 gamma-glutamyl semialdehyde (from arginine)
-42 Ornithine (from Arginine)
-34 Lysinoalanine (from Cysteine)
-34 Lanthionine (from Cysteine)
-34 Dehydroalanine (from Cysteine)
-30 Homoserine formed from Met by CNBr treatment
-27 Oxidation of arginine (to glutamic acid)
-18 Formylglycine (from cysteine)
-18 Pyroglutamic Acid formed from Glutamic Acid
-18 Dehydration (-H2O)
-18 S-gamma-Glutamyl (crosslinked to Cysteine)
-18 O-gamma-Glutamyl- (Crosslink to Serine)
-18 Serine to Dehydroalanine
-18 Alaninohistidine (Serine crosslinked to theta or pi carbon of Histidine)
-18 Misincorporation of Norleucine for Methionine
-18 Succinimide formation from aspartic acid
-17 Pyroglutamic Acid formed from Gln
-17 N-pyrrolidone carboxyl (N terminus)
-17 N alpha -(gamma-Glutamyl)-lysine
-17 N-(beta-Aspartyl)-Lysine (Crosslink)
-17 Succinimide formation from asparagine
-17 S-carbamoylmethylcysteine cyclization (N-terminus)
-16 Pyruvoyl- (Serine)
-5 Crosslink between Arg and His sidechains
-4 3,3',5,5'-TerTyr (Crosslink)
-2 Formylglycine (from serine)
-2 Disulphide bond formation (Cystine)
-2 S-(2-Histidyl)- (Crosslinked to Cysteine)
-2 S-(3-Tyr) (Crosslinked to Cysteine)
-2 3,3'-BiTyr (Crosslink)
-2 IsodiTyr (Crosslink)
-1 Allysine (from Lysine)
-1 Amide formation (C terminus)
-1 Oxidation of lysine (to aminoadipic semialdehyde)
1 Deamidation of Asparagine and Glutamine to Aspartate and Glutamate
1 Citruline (from Arginine)
2 Cysteine x2, reduction of Cystine (Cys-Cys)
2 Reduction of indole double bond of Trp
4 Oxidation of Trp to kynurenine
12 Lysine epsilon amino to imine
12 Cysteine (N-term) formaldehyde adduct (Cys to Thioproline conversion)
12 Formaldehyde adduct of Trp
13 Syndesine (from Lysine)
13 CM-Cys vs PAM-Cys
14 Methylation (N terminus, N epsilon of Lysine, O of Serine, Threonine or C terminus, N of Asparagine)
14 CAM-Cys vs PAM-Cys
14 Methylation (methyl esterification of Asp and Glu side chains)
15 delta-Hydroxy-allysine (from Lysine)
15 Oxidation of lysine (to aminoadipic acid)
16 Hydroxylation (of delta C of Lysine, beta C of Tryptophan, C3 or C4 of Proline, beta C of Aspartate)
16 Oxidation of Methionine (to Sulphoxide)
16 3,4-Dihydroxy-Phenylalanine (from Tyrosine) (DOPA)
16 Oxohistidine (from histidine)
16 Sulfenic Acid (from Cysteine)
16 Oxidation of proline (to gamma-glutamyl semialdehyde)
22 Sodium
28 Ethyl
28 N,N dimethylation (of Arginine or Lysine)
28 2,4-BisTrp-6,7-dione (from Tryptophan)
28 Formylation (CHO)
30 6,7 Dione (from Tryptophan)
32 3,4,6-Trihydroxy-Phenylalanine (from Tyrosine) (TOPA)
32 3,4-Dihydroxylation (of Proline)
32 Oxidation of Methionine (to Sulphone)
32 Oxidation of proline (to glutamic acid)
32 Double oxidation of Trp
32 Trisulfide bond (additional sulfur in disulfide bond)
34 3-Chlorination (of Tyrosine with 35Cl)
36 3-Chlorination (of Tyrosine with 37Cl)
38 Potassium
42 Acetylation (N terminus, N epsilon of Lysine, O of Serine) (Ac)
42 N-Trimethylation (of Lysine)
43 Carbamylation
44 disodium
45 Nitro (NO2)
46 beta-Methylthio-aspartic acid
48 Cysteic acid, oxidation of cysteine
51 Piperidine adduct to C-terminal Cys
56 t-butyl ester(OtBu) and t-butyl (tBu)
57 Glycyl (-G-,-Gly-)
57 Carboxamidomethyl (on Cysteine and other residues)
58 Carboxymethyl (on Cysteine and other residues)
60 sodium + potassium
64 Selenocysteine (from Serine)
67 Asp transamidation with piperidine
68 3,5-Dichlorination (of Tyrosine with 35Cl)
69 Dehydroalanine (Dha)
70 3,5-Dichlorination (of Tyrosine with mixture of 35Cl and 37Cl))
70 Pyruvate
71 Sarcosyl
71 Alanyl (-A-, -Ala-)
71 Acetamidomethyl (Acm)
71 Propionamide or Acrylamide adduct
72 3,5-Dichlorination (of Tyrosine with 37Cl)
74 S-(sn-1-Glyceryl) (on Cysteine)
74 Glycerol Ester (on Glutamic acid side chain)
75 Glycine (G, Gly)
76 Phenyl ester (OPh) (on acidic)
76 Beta mercaptoethanol adduct
78 3-Bromination (of Tyrosine with 79Br)
78 L-o-bromination of Phe with 79Br
80 L-o-bromination of Phe with 81Br
80 Sulphonation (SO3H) (of PMC group)
80 Sulphation (of O of Tyrosine)
80 Phosphorylation (O of Serine, Threonine, Tyrosine and Aspartate, N epsilon of Lysine)
80 3-Bromination (of Tyrosine with 81Br)
82 Cyclohexyl ester (OcHex)
83 Dehydroamino butyric acid (Dhb)
83 Homoseryl lactone
85 2-Aminobutyric acid (Abu)
85 2-Aminoisobutyric acid (Aib)
85 Gamma Aminobutyryl
86 t-butyloxymethyl (Bum)
86 Diaminopropionyl
87 N-(4-NH2-2-OH-butyl)- (of Lysine) (Hypusine)
87 Seryl (-S-, -Ser-)
88 t-butylsulfenyl (StBu)
89 Alanine (A, Ala)
89 Sarcosine (Sar)
90 Anisyl
90 Benzyl (Bzl) and benzly ester (OBzl)
93 1,2-ethanedithiol (EDT)
95 Dehydroprolyl
96 Trifluoroacetyl (TFA)
97 N-hydroxysuccinimide (ONSu, OSu)
97 Prolyl (-P-, -Pro-)
98 Cysteic acid x2, oxidation of cystine
98 Tetramethylguanidinium termination by-product on amine
98 Phosphate/sulphate adduct of proteins
99 Valyl (-V-, -Val-)
99 Isovalyl (-I-,-Iva-)
100 t-Butyloxycarbonyl (tBoc)
101 Threoyl (-T-, -Thr-)
101 Homoseryl (-Hse-)
103 Cystyl (-C-, -Cys-)
104 4-Methylbenzyl (Meb)
104 Benzoyl (Bz)
105 Serine (S, Ser)
105 Pyridylethylation of cysteine
106 HMP (hydroxymethylphenyl) linker
106 Thioanisyl
106 Thiocresyl
111 2-Piperidinecarboxylic acid (Pip)
111 Pyroglutamyl
113 Hydroxyprolyl (-Hyp-)
113 Isoleucyl (-I-, -Ile-)
113 Leucyl (-L-, -Leu-)
113 Norleucyl (-Nle-)
114 Asparagyl (-N-, -Asn-)
114 t-amyloxycarbonyl (Aoc)
114 Ornithyl (-Orn-)
115 Proline (P, Pro)
115 Aspartyl (-D-, -Asp-)
117 Succinyl
117 Valine (V, Val)
117 Hydroxybenzotriazole ester (HOBt)
118 Dimethylbenzyl (diMeBzl)
119 Threonine (T, Thr)
119 Cysteinylation
120 Benzyloxymethyl (Bom)
120 p-methoxybenzyl (Mob, Mbzl)
121 4-Nitrophenyl, p-Nitrophenyl (ONp)
121 Cysteine (C, Cys)
125 Chlorobenzyl (ClBzl)
126 Iodination (of Histidine[C4] or Tyrosine[C3])
126 octanoylation
128 Glutamyl (-Q-, -Gln-)
128 Lysyl (-K-, -Lys-)
129 Glutamyl (-E-, -Glu-)
129 O-Methyl Aspartamyl
130 N alpha -(gamma-Glutamyl)-Glu
131 Norleucine (Nle)
131 Hydroxyproline (Hyp)
131 Isoleucine (I, Ile)
131 Leucine (L, Leu)
131 Methionyl (-M-, -Met-)
131 Hydroxy Aspartamyl
131 bb-dimethyl Cystenyl
132 Asparagine (N, Asn)
132 Pentoses (Ara, Rib, Xyl)
133 Aspartic Acid (D, Asp)
134 Benzyloxycarbonyl (Z)
134 Adamantyl (Ada)
135 p-Nitrobenzyl ester (ONb)
137 Histidyl (-H-, -His-)
142 N-methyl Glutaminyl
142 N-methyl Lysyl
143 O-methyl Glutamyl
143 Diphthamide (from Histidine)
144 Hydroxy Lysyl (-Hyl-)
145 Methyl Methionyl
146 Glutamine (Q, Gln)
146 Deoxyhexoses (Fuc, Rha)
146 Lysine (K, Lys)
146 Pentosyl
146 Aminoethyl Cysteinyl (AECys)
147 4-Glycosyloxy- (pentosyl,C5) (of Proline)
147 Glutamic Acid (E, Glu)
147 Phenylalanyl- (-F-, -Phe-)
147 Methionyl Sulfoxide
148 Pyridyl Alanyl
149 2-Nitrobenzoyl (NBz)
149 Methionine (M, Met)
149 Fluorophenylalanyl
150 Dimethoxybenzyl Trp
153 2-Nitrophenylsulphenyl (Nps)
154 4-Toluenesulphonyl (Tosyl, Tos)
154 3-nitro-2-pyridinesulfenyl (Npys)
155 Histidine (H, His)
156 3,5-Dibromination (of Tyrosine with 79Br)
156 Arginyl (-R-, -Arg-)
157 Citrulline
158 3,5-Dibromination (of Tyrosine with mixture of 79Br and 81Br)
159 Dichlorobenzyl (Dcb)
160 3,5-Dibromination (of Tyrosine with 81Br)
160 Carboxyamidomethyl Cystenyl
161 Hexosamines (GalN, GlcN)
161 Carboxymethyl cysteine (Cmc)
161 Carboxymethyl Cystenyl
161 Methylphenylalanyl
162 Inositol
162 N-Glucosyl (N terminus or N epsilon of Lysine) (Aminoketose)
162 O-Glycosyl- (to Serine or Threonine)
162 Linker attached to peptide in Fmoc peptide synthesis
162 Hexoses (Fru, Gal, Glc, Man)
163 Tyrosinyl (-Y-, -Tyr-)
163 MethionylSulphone
165 Phenylalanine (F, Phe)
166 2,4 -dinitrophenyl (Dnp)
166 Pentaflourophenyl (Pfp)
166 Diphenylmethyl (Dpm)
167 Phospho Seryl
169 2-Chlorobenzyloxycarbonyl (ClZ)
169 Napthyl acetyl
170 N-acetyl Lysyl
170 N-methyl Arginyl
170 Decanoic acid modification of Cys in active site
172 Ethanedithiol/TFA cyclic adduct
173 Carboxy Glutamyl (Gla)
174 Arginine (R, Arg)
174 Acetamidomethyl Cystenyl
174 Acrylamidyl Cystenyl
176 N-Glucuronyl (N terminus)
177 delta-Glycosyloxy- (of Lysine) or beta-Glycosyloxy- (of Phenylalanine or Tyrosine)
177 4-Glycosyloxy- (hexosyl,C6) (of Proline)
177 Benzyl Seryl
177 N-methyl Tyrosinyl
178 a-N-Gluconoylation (His Tagged proteins)
179 p-Nitrobenzyloxycarbonyl (4Nz)
179 2,4,5-Trichlorophenyl
180 2,4,6-trimethyloxybenzyl (Tmob)
180 Xanthyl (Xan)
181 Tyrosine (Y, Tyr)
182 Chlorophenylalanyl
182 Mesitylene-2-sulfonyl (Mts)
183 AEBSF
184 Isopropyl Lysyl
186 Tryptophanyl (-W-, - Trp-)
186 Carboxymethyl Lysyl
188 N-Lipoyl- (on Lysine)
190 Matrix alpha cyano MH+
191 Benzyl Threonyl
193 Benzyl Cystenyl
197 Napthyl Alanyl
198 Succinyl Aspartamyl
201 HMP (hydroxymethylphenyl)/TFA adduct
203 N-acetylhexosamines (GalNAc, GlcNAc)
204 Tryptophan (W, Trp)
204 Cystine ((Cys)2)
204 Farnesylation
206 S-Farnesyl-
206 Myristoylation-4H (2 double bonds)
208 Myristoleylation (myristoyl with one double bond)
208 Pyridylethyl Cystenyl
210 Myristoylation
212 4-Methoxy-2,3,6-trimethylbenzenesulfonyl (Mtr)
213 2-Bromobenzyloxycarbonyl (BrZ)
214 Formyl Tryptophanyl
219 Benzyl Glutamyl
219 Anisole Adducted Glutamyl
222 9-Fluorenylmethyloxycarbonyl (Fmoc)
222 S-cystenyl Cystenyl
226 Biotinylation (amide bond to lysine)
226 Dimethoxybenzhydryl (Mbh)
229 N-Pyridoxyl (on Lysine)
231 Pyridoxal phosphate (Schiff Base formed to lysine)
233 Dansyl (Dns)
233 Nicotinyl Lysyl
238 2-(p-biphenyl)isopropyl-oxycarbonyl (Bpoc)
238 Palmitoylation
242 Triphenylmethyl (Trityl, Trt)
243 Tyrosinyl Sulphate
243 Phospho Tyrosinyl
252 Pbf (pentamethyldihydrobenzofuransulfonyl)
252 3,5-Diiodination (of Tyrosine)
258 a-N-6-Phosphogluconoylation (His Tagged proteins)
259 N alpha -(gamma-Glutamyl)-Glu2
266 Stearoylation
266 Pmc (2,2,5,7,8- Pentamethylchroman-6-sulphonyl)
272 Geranylgeranylation
272 Monomethoxytrityl
276 S-Geranylgeranyl
283 O-GlcNAc-1-phosphorylation (of Serine)
289 5'phos dCytidinyl
289 iodo Tyrosinyl
290 Aldohexosyl Lysyl
291 Sialyl
291 N-acetylneuraminic acid (Sialic acid, NeuAc, NANA, SA)
304 5'phos dThymidinyl
305 5'phos Cytidinyl
305 Glutathionation
306 O-Uridinylylation (of Tyrosine)
306 5'phos Uridinyl
307 N-glycolneuraminic acid (NeuGc)
307 S-farnesyl Cystenyl
313 5'phos dAdenosyl
324 O-pantetheinephosphorylation (of Serine)
327 SucPhencarb Lysyl
329 5'phos dGuanosyl
329 5'phos Adenosinyl
329 O-5'-Adenosylation ( of Tyrosine)
339 4'-Phosphopantetheine
342 S-palmityl Cystenyl
345 5'phos Guanosyl
354 Biotinyl Lysyl
359 Fluorescein labelling of peptide N-terminal using NHS ester
365 Hex-HexNAc
388 N alpha -(gamma-Glutamyl)-Glu3
391 Dioctyl Phthalate
395 PMC Lysyl
409 Aedans Cystenyl
413 Dioctyl Phthalate Sodium Adduct
415 di-iodo Tyrosinyl
423 PMC Arginyl
454 S-Coenzyme A
457 AMP Lysyl
470 3,5,3'-Triiodothyronine (from Tyrosine)
524 S-(sn-1-Dipalmitoyl-glyceryl)- (on Cysteine)
541 S-(ADP-ribosyl)- (on Cysteine)
541 N-(ADP-ribosyl)- (on Arginine)
541 O-ADP-ribosylation (on Glutamate or C terminus)
541 ADP-rybosylation (from NAD)
587 S-Phycocyanobilin (on Cysteine)
617 S-Heme (on Cysteine)
648 N theta -(ADP-ribosyl) diphthamide (of Histidine)
657 NeuAc-Hex-HexNAc
783 O-8 alpha-Flavin [FAD])- (of Tyrosine)
784 S-(6-Flavin [FAD])- (on Cysteine)
784 N theta and N pi-(8alpha-Flavin) (on Histidine)
893 (Hex)3-HexNAc-HexNAc
1,039 (Hex)3-HexNAc-(dHex)HexNAc