Versatile peroxidase of Bjerkandera fumosa: Substrate and inhibitor specificity
The inhibitor and substrate specificities of versatile peroxidase from Bjerkandera fumosa (VPBF) were studied. Two different effects were found: NaN3, Tween-80, anthracene, and fluorene decreased the activity of VPBF, but p-aminobenzoic acid increased it. A mixed mechanism of effector influence on the activity of this enzyme was shown. The catalytic properties of VPBF in the oxidation of mono- and polycyclic aromatic compounds were studied also. 2,7-Diaminofluorene, ABTS, veratryl alcohol, and syringaldazine can be oxidized by VPBF in two ways: either directly by the enzyme or by diffusible chelated Mn3+ as an oxidizing agent. During VPBF oxidation of 2,7-diaminofluorene, both with and without Mn2+, biphasic kinetics with apparent saturation in both micromolar and millimolar ranges were obtained. In the case of ABTS, inhibition of VPBF activity by an excess of substrate was observed. Direct oxidation of p-aminobenzoic acid by versatile peroxidase was found for the first time. The oxidation of three- and four-ring PAHs by VPBF was investigated, and the oxidation of anthracene, phenanthrene, fluorene, pyrene, chrysene, and fluoranthene was shown. The products of PAH oxidation (9,10-anthraquinone, 9,10-phenanthrenequinone, and 9-fluorenone) catalyzed by VPBF were identified.
► The mixed mechanism of effectors on activity of versatile peroxidase was showed. ► The inhibition of versatile peroxidase (VPBF) activity by excess of ABTS was observed. ► Biphasic kinetic of 2,7-diaminofluorene oxidation by VPBF was obtained. ► The direct oxidation of p-aminobenzoic acid by versatile peroxidase was found. ► The quinone products of PAH oxidation by VPBF were identified.
Journal: Enzyme and Microbial Technology - Volume 52, Issue 1, 10 January 2013, Pages 44–53