derives from alpha-amino propanoylated residue alpha-amino 3x(13)C-labeled propanoylated residue 187.1312408447265625 187.2100067138671875 59.03627777099609375 59.04000091552734375 Propionyl:13C(3) X H 4 (13)C 3 O 1 A protein modification that effectively replaces a residue alpha-amino- or alpha-imino-hydrogen with a 3x(13)C-labeled propanoyl group. PSI-MOD Propionate labeling reagent heavy form (+3amu), N-term & K MOD:00452 N-term artifact C 6 H 16 (13)C 3 N 2 O 2 isotope tagged reagent derivatized residue (13)C isotope tagged reagent