Lytic polysaccharide monooxygenase (LPMO) that depolymerizes crystalline and amorphous polysaccharides via the oxidation of scissile alpha- or beta-(1-4)-glycosidic bonds, yielding C1 or C4 oxidation products. Catalysis by LPMOs requires the reduction of the active-site copper from Cu(II) to Cu(I) by a reducing agent and H(2)O(2) or O(2) as a cosubstrate. The synergistic activity of LPMO9B with xylanase Xyl10G or cellulase Cel5B shows efficient bioconversion rates of 56 and 174 percent in pretreated kenaf (Hibiscus cannabinus) and oak, respectively