Functional characterization of Clonostachys rosea LPMOs

Wider research context: Lytic polysaccharide monooxygenases (LPMOs) are powerful enzymes that oxidatively cleave glycosidic bonds in polysaccharides, thus boosting the activity of well-known hydrolytic depolymerizing enzymes. The process involves molecular oxygen/hydrogen peroxide and an electron donor, such as enzymes of GMC oxidoreductase family (e.g. cellobiose dehydrogenase), small-molecule reductants or photoactive pigments. Clonostachys rosea (Hypocreales, Ascomycota) is a filamentous fungus that colonizes living plants as an endophyte, and parasitizes on and kills other fungi (necrotrophic mycoparasite). Upon sequencing of the C. rosea genomes, the gene family encoding LPMOs (AA9), as well as the GMC oxidoreductase family (AA3) were found to be significantly expanded. In contrast, the genomes of the saprotrophic and mycoparasitic Trichoderma species (ecologically very similar to C. rosea) have significantly low number of AA9 and AA3 genes. Research objectives: We aim to unravel the catalytic activities and substrate specificities of C. rosea novel LPMOs, identify new structure-function aspects in combination with biochemical characterizations, and study their synergies with other native C. rosea enzymes such as GMC oxidoreductases.