Unravelling yeast cellulase potential: A computational approach to structural study, cellulolytic activity, and docking

Abstract

The discovery of highly efficient catalysts capable of enhancing the biomass conversion represents a significant challenge within the biofuel production sector. Cellulolytic enzymes originating from microorganisms are promising catalysts for bioethanol conversion. In this study, we conducted a comparative analysis of cellulase, especially Endo β-1,4 glucanase enzymes, from five different non-conventional yeast species. These enzymes were evaluated in the presence of microcrystalline cellulose as the substrate, and their structural, physicochemical properties and molecular docking were studied using in silico screening techniques. During multiple sequence alignment, we identified conserved catalytic amino residues in yeast cellulases, highlighting the pivotal role of glutamic acid in cellulose hydrolysis. Using InterProScan, we determined that the obtained sequence belonged to the GH5 and GH45 families and domains. The key amino acid residues involved in the interaction were glutamic acid, serine, alanine, arginine, asparagine, and histidine. Notably, the docking score for Candida fabianii was significantly lower (-12.95kcal/mol) than that of the other enzymes, indicating a strong affinity for cellulose. In conclusion, our results underscore the importance of a key amino acid residue in Endo β-1,4 glucanase from Candida fabianii, which may enhance the selectivity of endoglucanase toward cellulose.