Controlled depolymerization of cellulose by light-driven lytic polysaccharide oxygenases

• Published in: Nature communications 2020-02, Vol.11 (1), p.890-12, Article 890
• Main Authors: Bissaro, Bastien, Kommedal, Eirik, Røhr, Åsmund K., Eijsink, Vincent G. H.
• Format: Article
• Language: English
• Subjects: 631/45/603; 639/638/92/173; 82/16; 82/80; 82/83; Biocatalysis; Biotechnology; Cellulose - chemistry; Cellulose - metabolism; Enzyme Stability; Fungal Proteins - chemistry; Fungal Proteins - genetics; Fungal Proteins - metabolism; Humanities and Social Sciences; Hydrogen Peroxide - metabolism; Kinetics; Life Sciences; Light; multidisciplinary; Oxygenases - chemistry; Oxygenases - genetics; Oxygenases - metabolism; Polymerization - radiation effects; Science; Science (multidisciplinary); Streptomyces coelicolor - chemistry; Streptomyces coelicolor - enzymology; Streptomyces coelicolor - genetics; Streptomyces coelicolor - radiation effects
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-020-14744-9

Lytic polysaccharide (mono)oxygenases (LPMOs) perform oxidative cleavage of polysaccharides, and are key enzymes in biomass processing and the global carbon cycle. It has been shown that LPMO reactions may be driven by light, using photosynthetic pigments or photocatalysts, but the mechanism behind this highly attractive catalytic route remains unknown. Here, prompted by the discovery that LPMOs catalyze a peroxygenase reaction more efficiently than a monooxygenase reaction, we revisit these light-driven systems, using an LPMO from Streptomyces coelicolor ( Sc AA10C) as model cellulolytic enzyme. By using coupled enzymatic assays, we show that H 2 O 2 is produced and necessary for efficient light-driven activity of Sc AA10C. Importantly, this activity is achieved without addition of reducing agents and proportional to the light intensity. Overall, the results highlight the importance of controlling fluxes of reactive oxygen species in LPMO reactions and demonstrate the feasibility of light-driven, tunable enzymatic peroxygenation to degrade recalcitrant polysaccharides. Lytic polysaccharide (mono)oxygenases (LPMOs) perform oxidative cleavage of polysaccharides. Here, the authors showed that the light-driven activity of LPMOs is dependent on hydrogen peroxide availability and can be controlled via the light intensity provided.