Characterization of Dye-decolorizing Peroxidase (DyP) from Thermomonospora curvata Reveals Unique Catalytic Properties of A-type DyPs

摘要: Dye-decolorizing peroxidases (DyPs) comprise a new family of heme peroxidases, which has received much attention due to their potential applications in lignin degradation. A DyP from Thermomonospora curvata (TcDyP) was identified and characterized. Unlike other A-type enzymes, TcDyP is highly active toward wide range substrates including model compounds, the catalytic efficiency with ABTS (kcatapp/Kmapp = (1.7 × 107) m−1 s−1) close that fungal DyPs. Stopped-flow spectroscopy employed elucidate transient intermediates as well cycle involving wild-type (wt) mutant TcDyPs. Although residues Asp220 Arg327 are found necessary for compound I formation, His312 proposed play roles II reduction. Transient kinetics hydroquinone (HQ) oxidation by wt-TcDyP showed conversion resting state rate-limiting step, will explain contradictory observation made aspartate mutants Moreover, replacement significant effects on oligomerization redox (E°′) enzyme. Both were promote formation dimeric shift E°′ more negative potential. Not only do these results reveal unique property DyPs, but they also facilitate development enzymes degraders.