title: The interaction of catalytic metal ions and ionizing groups in equilibrium studies and in transient intermediates of metal-substituted alcohol dehydrogenases.
abstract: The step of ternary complex interconversion in the reaction catalyzed by horse liver alcohol dehydrogenase has been resolved into five distinct molecular species with the aid of metal-substitution studies in combination with rapid-scanning spectrophotometry. A correlation with electronic absorption spectra at equilibrium provides structural insights into these intermediates. In contrast to NADH, NAD+ only leads to a conformational change of the protein when a negative charge has been created in the vicinity of the catalytic metal ion. This paper presents also a reevaluation of previous assignments of catalytically important groups in the light of some recent results.
mesh_terms: D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites; D002104:Cadmium / Q000378:metabolism; D002384:Catalysis; D003035:Cobalt / Q000378:metabolism; D003300:Copper / Q000378:metabolism; D006736:Horses; D008099:Liver / Q000201:enzymology*; D046911:Macromolecular Substances; D008670:Metals / Q000378:metabolism*; D015032:Zinc / Q000378:metabolism
chemical_list: D046911:Macromolecular Substances; D008670:Metals; D002104:Cadmium; D003035:Cobalt; D003300:Copper; D000429:Alcohol Oxidoreductases; D015032:Zinc