Lignocellulosic biomass is a renewable and low-cost source of energy, emerging as an alternative to the use of fossil fuels. Due to its recalcitrant nature, the use of an arsenal of enzymes is required for its deconstruction into fermentable sugars, what increase the costs related to the production of second generation (2G) ethanol. In this regard, enzymes currently classified as Auxiliary Activity 9 and 10 (AA9 and AA10) or Lytic Polysaccharide Monooxygenases (LPMOs) emerge as boosters of (hemi) cellulase activities reducing the loading of canonical enzymes on reaction. AA10 are produced mainly by bacterial strains and several studies pointed out their role in increasing the release of sugars from synthetical and natural biomasses when these enzymes are added to the reaction with cellulases. By this way, the aims of this project were the selection, cloning, purification, characterization and application of new sources of AA10 on lignocellulosic biomass deconstruction aiming the production of ethanol 2G.