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A novel Lytic Polysaccharide Monooxygenase (LPMO) family AA9 (PMO9A_MALCI) protein from thermophilic fungus Malbranchea cinnamomea was cloned and expressed in Pichia pastoris. The expressed protein was purified to homogeneity using ion exchange and hydrophobic interaction chromatography. SDS-PAGE analysis showed PMO9A_MALCI to be ~27 kDa protein. High performance anion exchange chromatography and mass spectrometry confirmed that purified protein was active against an array of cellulosic (avicel, carboxy methyl cellulose) and hemicellulosic (birch wood xylan, wheat arabinoxylan and rye arabinoxylan) substrates, releasing both oxidized and unoxidized cello-oligosaccharide and xylo-oligosaccharide products respectively. Presence of double oxidized products during mass spectrometric analysis as well as in-silico analysis confirmed that the expressed protein belongs to Type 3 …