methylated glycine alpha-amino trimethylated protonated-residue N,N,N-trimethylglycine (trimethylammonio)ethanoic acid 1+ 1-carboxy-N,N,N-trimethylmethanazanium 101.0840606689453125 101.15000152587890625 2-trimethylammonioacetate 43.054775238037109375 43.090000152587890625 C 3 H 7 N 0 O 0 C 5 H 11 N 1 O 1 G MOD:01982 MOD_RES N,N,N-trimethylglycine N,N,N-trimethylglycine cation N,N,N-trimethylglycinium N-term N2Me3+Gly PSI-MOD betaine carboxy-N,N,N-trimethylmethanaminium carboxymethyl-trimethylazanium glycine betaine modification from RESID natural uniprot.ptm:PTM-0485