Collect. Czech. Chem. Commun. 2001, 66, 663-675

To the Mechanism of Horseradish Peroxidase-Mediated Degradation of a Recalcitrant Dye Remazol Brilliant Blue R

Markéta Mikšanováa, Jiří Hudečeka, Jan Pácab and Marie Stiborováa,*

a Department of Biochemistry, Charles University, 128 40 Prague 2, Czech Republic
b Department of Fermentation Chemistry and Bioengineering, Institute of Chemical Technology, Prague, 166 28 Prague 6, Czech Republic


The in vitro enzymatic metabolism of a recalcitrant dye Remazol Brilliant Blue R (RBBR) was investigated using horseradish peroxidase (HRP). At optimum pH (4.5), the apparent Michaelis constant (KM) value for the oxidation of RBBR catalyzed by HRP is 14.8 μmol l-1. HRP-mediated conversion of RBBR proceeds via a conventional peroxidase reaction, by a sequential one-electron oxidation of two molecules of RBBR by the peroxidase Compounds I and II. The oxidation is inhibited by radical trapping agents (nicotinamide adenine dinucleotide reduced (NADH), ascorbate, glutathione). This confirms that the peroxidase-mediated oxidation of RBBR proceeds via radical mechanism. Gel permeation profile of the RBBR oxidation products shows that the pattern of molecular weight distribution was shifted to the higher molecular weight region indicating formation of RBBR oligomers. In addition to HRP, the RBBR dye is also oxidized by another peroxidase, the mammalian lactoperoxidase.

Keywords: Recalcitrant organopollutants; Biodegradation; Peroxidases; Enzyme reaction mechanism; Metabolism; Anthracenes; Quinones; Sulfonates; Dyes.

References: 31 live references.