Fungal laccases are industrially important enzymes,that have great potential as biocatalysts oxidizing a variety of aromatic compounds using water as the sole by-product. Inthis work, Trametes versicolor laccase (TvL) enzyme, including nineN-acetyl D-glucosamines (NAG) which are attached to the protein scaffold on the six positions viathe glycosidic bonds. No other type of sugars was found in contrast to other fungal laccases. Removal of N-glycans from TvLleads to increase the hydrophobicity of the enzyme, as well as the reductionof stability and the catalyticreactions. However,due to the lack of the proper force field for the glycans, they are ignored in the theoretical studies. The present study aims to assess the effects of the N-glycan structure, stability and activity of TvLthrough the simulation of the native and the deglycosated structures. Molecular dynamics(MD)simulation results reveal that the removal of N-glycans increases the number of the cavities from eleven to sixteen. However, the removal of glycans is associated with reducing the channels providing the substrate access. The removal of the N-glycan segments induces the significant changes in the flexibility of the residues that affect the enzyme activities.

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