title: Chemiluminescent oxidation of ribose catalyzed by horseradish peroxidase in presence of hydrogen peroxide.
abstract: The reaction of ribose with horseradish peroxidase in the presence of H2O2 is accompanied by light emission. The detection of horseradish peroxidase Compound II (FeO2+) indicates that the enzyme participates in a normal peroxidatic cycle. Hydrogen peroxide converts horseradish peroxidase into Compound 1 (FeO2+) which in turn is converted into Compound II by abstracting a hydrogen atom from ribose forming a ribosyl radical. In aerated solutions oxygen rapidly adds to the ribosyl radical. Based on the spectral characteristics and the enhancement of the chemiluminescence by chlorophyll-a, xanthene dyes, D2O and DABCO, it is suggested that the excited species, apparently triplet carbonyls and 1O2, are formed from the biomolecular decay of the peroxyl radicals via the Russell mechanism.
authors.affiliation: Institut für Physiologische Chemie 1, Universität Düsseldorf, Federal Republic of Germany.
authors.forename: M H
authors.initials: MH
authors.lastname: Medeiros
authors.forename: H
authors.initials: H
authors.lastname: Sies
mesh_terms: D006735:Horseradish Peroxidase / Q000378:metabolism*; D006861:Hydrogen Peroxide; D007700:Kinetics; D008163:Luminescent Measurements; D009005:Monosaccharides; D010084:Oxidation-Reduction; D010544:Peroxidases / Q000378:metabolism*; D012266:Ribose; D013053:Spectrophotometry
chemical_list: D009005:Monosaccharides; D012266:Ribose; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase; D010544:Peroxidases