Spectroscopy ascorbate peroxidases

The resonance Raman spectrum of the class III ascorbate peroxidase isoenzyme II from tea leaves was consistent with an unusual five-coordinate quantum mechanically mixed-spin haem. Porphyrin-ring oxidation state marker bands were assigned for a range of Ru (Por)L2 complexes, where Por = TPP and substituted derivatives, L = PhNO. IR spectroscopy was used to probe the coupling of ground state molecular vibrations with low-energy electronic transitions of Ru(III, II) porphyrin dimer species. ... [Pg.299]

Aminophthalate anion Atmospheric pressure active nitrogen Analyte pulse perturbation-chemiluminescence spectroscopy Arthromyces rasomus peroxidase Ascorbic acid Adenosine triphosphate Avalanche photodiode 5-Bromo-4-chloro-3-indolyl 2,6-Di-t< r/-bu(yl-4-mclhyl phenol Bioluminescence Polyoxyethylene (23) dodecanol Bovine serum albumin Critical micelle concentration Calf alkaline phosphatase Continuous-addition-of-reagent Continuous-addition-of-reagent chemiluminescence spectroscopy Catecholamines Catechol... [Pg.594]

The oxidation of ascorbic acid in certain reactions has given evidence of an intermediate with the properties of a free radical which could be formed by one-electron oxidation. Thus, the rate-limiting step of ascorbic acid oxidation by Fe + and H2O2 was this one-electron oxidation (G12). Such a radical has now been identified in hydrogen peroxide-ascorbic acid solutions at pH 4.8 by electron paramagnetic resonance spectroscopy. The free radical, commonly referred to as monodehydroascorbic acid, decayed in about 15 minutes at this acid pH. It was also formed during the enzymatic oxidation of ascorbic acid by peroxidase (Yl). The existence of the monodehydroascorbic acid radical makes possible very... [Pg.130]