FAD modified residue modified L-aspartic acid residue O4-(8alpha-FAD)-L-aspartate (2S)-2-amino-4-oxo-4-[8alpha-riboflavin 5'-(trihydrogen diphosphate) 5'->5'-ester with adenosine]oxybutanoic acid 783.1414794921875 783.53997802734375 898.16845703125 898.6300048828125 8alpha-[(4-aspartyl)oxy]FAD A protein modification that effectively converts an L-aspartic acid residue to O4-(8alpha-FAD)-L-aspartate. C 27 H 31 N 9 O 15 P 2 C 31 H 36 N 10 O 18 P 2 D MOD:01668 O4-(8alpha-FAD)-L-aspartate PSI-MOD natural