1.1.9.1 heme heme group participates in enzymatic mechanism 389953 1.1.9.1 pyrroloquinoline quinone - 389953 1.1.9.1 heme binding of pyrroloquinoline quinone induces shifts in the resonances of the methyl groups of the heme porphyrin ring in the oxidized form of the apoenzyme and a shift in the methionine heme ligand resonance of the reduced form of the apoenzyme. A major effect of pyrroloquinoline quinone binding to apo-QH-EDH is a rotation of the methionine ligand of heme c. Pyrroloquinoline quinone becomes tightly bound, the event leading to a compact enzyme conformation which is able to catalyze rapid intramolecular electron transfer 389956 1.1.9.1 pyrroloquinoline quinone binding of pyrroloquinoline quinone induces shifts in the resonances of the methyl groups of the heme porphyrin ring in the oxidized form of the apoenzyme and a shift in the methionine heme ligand resonance of the reduced form of the apoenzyme. A major effect of pyrroloquinoline quinone binding to apo-QH-EDH is a rotation of the methionine ligand of heme c. Pyrroloquinoline quinone becomes tightly bound, the event leading to a compact enzyme conformation which is able to catalyze rapid intramolecular electron transfer 389956 1.1.9.1 heme holoenzyme contains equimolar amounts of pyrroloquinoline quinone, Ca2+ and covalently bound heme. Low-spin heme protein 389960 1.1.9.1 pyrroloquinoline quinone holoenzyme contains equimolar amounts of pyrroloquinoline quinone, Ca2+ and covalently bound heme. Reconstitution of apoenzyme with pyrroloquinoline quinone analogues results in a decreased activity and enantioselectivity for the oxidation of chiral alcohols. Possession of the o-quinone or o-quinol moiety is not essential for binding but it is for activity 389960 1.1.9.1 heme - 678768 1.1.9.1 heme c both isoforms ADH IIB and ADH IIG 687362 1.1.9.1 pyrroloquinoline quinone both isoforms ADH IIB and ADH IIG 687362 1.1.9.1 heme in the crystals, the four hemes in the unit cell have only two different orientations, related by an 180° rotation about the b axis. The heme rings are oriented parallel to the b axis 701480