Methylation
| Kingdom | Residues | Position | Rule |
|---|---|---|---|
| all | C,K,R,H,D,E,N,Q | anywhere (but not N-terminus) | - |
| Eukaryotes | P,A | N-terminus | - |
| Prokaryotes | A | N-terminus | - |
| Prokaryotes | F,Y,I,L,M | N-terminus after cleavage of signal peptide | rule PS00409: Consensus pattern [KRHEQSTAG]-G-[FYLIVM]-[ST]-[LT]-[LIVP]-E-[LIVMFWSTAG](14) |
Mass differences:
| METH | DIMETH | TRIMETH | |
|---|---|---|---|
| average | 14.0269 | 28.0538 | 42.08 |
| monoisotopic | 14.0157 | 28.0314 | 42.046950 |