2-pyrrolidone-5-carboxylic acid (Glu) -18.010564804077148438 -18.020000457763671875 112.03985595703125 112.1100006103515625 H -2 O -1 PyrGlu(Glu) 2-pyrrolidone-5-carboxylic acid N-term E 5-pyrrolidone-2-carboxylic acid 5-oxopyrrolidine-2-carboxylic acid From DeltaMass: References: The conversion of glutamic acid to pyroglutamic was reported for the beta-amyloid protein. Miller et al. Arch. Biochem. Biophy. (1993) 301, 41-52 [DeltaMass]. The modification in amyloid protein is probably an artifact of treatment with strong acid under anhydrous conditions. Peptides with N-terminal glutamic acid isolated from single cells of Aplysia neurons show partial conversion to pyroglutamic acid, possibly dependent on a temperature sensitive factor [JSG]. MOD:00420 5-oxoproline 2-oxopyrrolidine-5-carboxylic acid PSI-MOD Pyroglutamic Acid formed from Glutamic Acid A protein modification that effectively converts an L-glutamic acid residue to 2-pyrrolidone-5-carboxylic acid. (2S)-5-oxo-2-pyrrolidinecarboxylic acid PCA artifact ntermpeppyroe pyroglutamic acid Pyro-glu from E MOD_RES Pyrrolidone carboxylic acid (Glu) C 5 H 6 N 1 O 2 Glu->pyro-Glu modified L-glutamic acid residue 2-pyrrolidone-5-carboxylic acid