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:

METHDIMETHTRIMETH
average 14.026928.053842.08
monoisotopic 14.015728.031442.046950