Comprehensive in silico and gene expression profiles of MnP family genes in Phanerochaete chrysosporium towards lignin biodegradation

Abstract

Phanerochaete chrysosporium (Pc) is the primary fungal source for Lignin degrading enzymes (LDEs). A comprehensive in silico and gene expression analysis was carried out for one of the most important LDEs called manganese peroxidases (PcMnPs). We have identified five PcMnPs in BLAST genomic survey, which are putatively glycosylated extracellular proteins (39–40 kDa). These contain putative regulatory motifs for various factors, like, stress, metal ions, and nutrient components, peroxidase and ligninase motifs, and secretory signal peptides. PcMnPs also exhibit potent variation in transcript accumulation in time and stress-specific manner. Interestingly, PcMnPs were significantly expressed at later growth stages (144 h) and also found to be induced by different stresses and cofactors, such as, MnSO4, H2O2 and heat stress. Particularly, PcMnP1, PcMnP3, and PcMnP4 showed elevated expression in different time intervals and also under different concentration of nutritional components and stress treatments. In addition, molecular modeling and gene expression results indicate that PcMnP1 might serve as a potential candidate for lignin biodegradation. The present study revealed the structural variations and functioning of different modes of regulation of expression of the PcMnPs, which would be useful for the improvement of biodegradation of lignocelluloses and other recalcitrant wastes.