The synergism of manganese peroxidase and laccase from Cerrena unicolor BBP6 in denim dye decolorization and the construction of gene co-expression system in Pichia pastoris

Two types of extracellular ligninolytic enzymes of white-rot fungi, i.e., laccase and manganese peroxidase (MnP), are commonly in denim bleaching process due to their superior degradation capability of synthetic dyes. In the process of bleaching by extracellular broth of Cerrena unicolor BBP6, MnP was primarily responsible for the decolorization of denims, while laccase played an assisting role in the decolorizing reaction by participating in the production of HO to initiate the catalytic reaction of MnP. A gene co-expression system in Pichia pastoris was constructed based on the synergism of both MnP and laccase, showing a significantly enhanced decolorization effect on denims. Our results demonstrated that the recombinant enzyme complex (rMnP3-BBP6 and rLacA-189) has shown promising application potential in textile industries, especially in denim bleaching process.