Dopa and structurally related catecholamines in presence of hydrogen peroxide are oxidized in vitro by soybean lipoxygenase producing the corresponding melanin pigments. The kinetic parameters of the catecholasic reaction, measured as aminochrome formation, have been calculated. The rate of peroxidation depends on catecholamine and hydrogen peroxide concentration. The optimum: pH for the peroxidative activity of the enzyme is around 8.5. The enzyme, at higher pH values (pH 9 - 9.5), is also able to perform an oxidative reaction of the substrates. Implications of the possible biochemical relevance of the reactions are discussed. (C) 1994 Academic Press, Inc.
LIPOXYGENASE-CATALYZED OXIDATION OF CATECHOLAMINES / Rosei, Maria Anna; Blarzino, Carla; C., Foppoli; Mosca, Luciana; Coccia, Raffaella. - In: BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS. - ISSN 0006-291X. - 200:1(1994), pp. 344-350. [10.1006/bbrc.1994.1454]
LIPOXYGENASE-CATALYZED OXIDATION OF CATECHOLAMINES
ROSEI, Maria Anna;BLARZINO, Carla;MOSCA, Luciana;COCCIA, Raffaella
1994
Abstract
Dopa and structurally related catecholamines in presence of hydrogen peroxide are oxidized in vitro by soybean lipoxygenase producing the corresponding melanin pigments. The kinetic parameters of the catecholasic reaction, measured as aminochrome formation, have been calculated. The rate of peroxidation depends on catecholamine and hydrogen peroxide concentration. The optimum: pH for the peroxidative activity of the enzyme is around 8.5. The enzyme, at higher pH values (pH 9 - 9.5), is also able to perform an oxidative reaction of the substrates. Implications of the possible biochemical relevance of the reactions are discussed. (C) 1994 Academic Press, Inc.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
