pyrroloquinoline quinone 330.012420654296875 330.209991455078125 37.906494140625 37.9199981689453125 coenzyme PQQ pyrroloquinoline quinone E, Y CROSSLNK Pyrroloquinoline quinone (Glu-Tyr) A protein modification that effectively doubly cross-links an L-glutamic acid residue and an L-tyrosine residue with a carbon-carbon bond and a carbon-nitrogen bond to form pyrroloquinoline quinone. methoxatin H -10 O 3 natural 4,5-dihydro-4,5-dioxo-1H-pyrrolo[2,3-5,6]quinoline-2,7,9-tricarboxylic acid 2,4,6-tricarboxylic-pyrrolo[2,3-5,6]quinoline 8,9-quinone MOD:00288 C 14 H 6 N 2 O 8 PSI-MOD Cross-link 2. 2,7,9-tricarboxy-1H-pyrrolo(2,3-f)quinoline-4,5-dione none uncategorized crosslinked residues crosslinked L-glutamic acid residue crosslinked L-tyrosine residue