Pyrroloquinoline Quinone Synthase

Pyrroloquinoline quinone (PQQ) is a cofactor found in a class of proteins known as quinoproteins. The enzyme PQQ synthase (PQQC) catalyzes the final step in the pathway in a reaction that involves ring cyclization and the eight-electron oxidation of 3a-(2-amino-2-carboxyethyl)-4,5-dioxo-4,5,6,7,8,9-hexahydroquinoline-7,9-dicarboxylic-acid with molecular oxygen to form PQQ. The model of PQQC showing PQQ and oxygen as they are bound to the enzyme was presented to Professor Judith Klinman, University of California, Berkeley, on the occasion of her 70th birthday in 2011. She has continues studying the enzyme. The sculpture, made of nickel plated brass, stands 22 inches above a granite base.