BIOCHEMICAL AND STRUCTURAL CHARACTERIZATION OF DYE DECOLORIZING PEROXIDASE FROM BACILLUS SUBTILIS

Abstract

Dye-decolorizing peroxidases (DyPs) are a new family of heme-containing peroxidase, which have been reported in a wide range of bacteria and fungi. DyPs differ significantly from other well-known heme peroxidases such as horseradish peroxidase and class II peroxidase in relation to primary sequence, tertiary structures, catalytic residues, and substrate specificity. Based on the sequence homology, the DyPs have been sub-classified into four distinct classes, i.e., Class A, B, C, and D. The crystal structures from every class have been elucidated to explain the catalytic mechanism. However, class A-type DyPs are not yet well characterized regarding the substrate-binding sites. The aim of the work presented in this thesis, entitled “Biochemical and structural characterization of dye decolorizing peroxidase (DyP) from Bacillus subtilis” was to biochemically and structurally characterize the DyP involved in the oxidation of various types of dyes as well as lignin-related model compounds and wheat straw lignocellulose. The present work was carried out on DyP from Bacillus subtilis, which belongs to class A-type of DyP.