Transcriptomic analysis ofLentinus squarrosulusprovide insights into its biodegradation ability

Abstract

AbstractBasidiomycetes are of special interest in biotechnological research for their versatile potential in degradation of lignocellulosic biomass. This study accordingly reports analysis of transcriptome of a white-rot BasidiomyceteL.squarrosulusgrown in simple potato dextrose broth supplemented with aromatic compound, reactive black dye to gain an insight into the degradation ability of the fungus. RNA was sequenced using Illumina NextSeq 500 to obtain 6,679,162 high quality paired end reads that were assembledde novousing CLC assembly cell to generate 25,244 contigs.Putative functions were assigned for the 10,494 transcripts based on sequence similarities through BLAST2GO 5.2 and Function annotator. Functional assignments revealed enhanced oxidoreductase activity through the expression of diverse biomass degrading enzymes and their corresponding co-regulators. CAZyme analysis through dbCAN and CUPP revealed the presence of 6 families of polysaccharide lyases, 51 families of glycoside hydrolases, 23 families of glycoside transferases, 7 families of carbohydrate esterases and 10 families of Auxiliary activities.Genes encoding the ligninolytic enzymes and auxiliary activities among the transcript sequences were identified through gene prediction by AUGUSTUS and FGENESH. Biochemical analysis of a couple of biomass degrading enzymes substantiated the functional predictions. In essence,L.squarrosulusgrown in a simple medium devoid of lignocellulosic substrate demonstrated presence of a repertoire of lignocellulose degrading enzymesimplying that source of lignocellulose is not required for expression of these biomass degrading enzymes. The study hereby underlines the significance ofL.squarrosulusin biomass degradation and its future functional exploitation in biomass conversion applications.