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Lignocellulosic biomass is rich in lignins, which represent a bottomless natural source of aromatic compounds. Due to the high chemical complexity of these aromatic polymers, their biological fractionation remains challenging for biorefinery. The production of aromatics from the biological valorisation of lignins requires the action of ligninolytic peroxidases and laccases produced by fungi and bacteria. Therefore, identification of efficient ligninolytic enzymes with high stability represents a promising route for lignins biorefining. Our strategy consists in exploiting the enzymatic potential of the thermophilic bacterium, Thermobacillus xylanilyticus to produce robust and thermostable ligninolytic enzymes. In this context, a gene encoding a putative catalase-peroxidase was identified from the bacterial genome. The present work describes the production of the recombinant protein, its biochemical characterisation and ligninolytic potential. Our results show that the catalase-peroxidase from T. xylanilyticus is thermostable and exhibits catalase-peroxidase and manganese peroxidase activities. The electrochemical characterization using intermittent pulse amperometry showed the ability of the enzyme to oxidize small aromatic compounds derived from lignins. This promising methodology allows the fast screening of the catalase-peroxidase activity towards small phenolic molecules, suggesting its potential role in lignin transformation.