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Background Major cost of bioethanol is attributed to enzymes employed in biomass hydrolysis. Biomass hydrolyzing enzymes are predominantly produced from the hyper-cellulolytic mutant filamentous fungus Trichoderma reesei RUT-C30. Several decades of research have failed to provide an industrial grade organism other than T. reesei, capable of producing higher titers of an effective synergistic biomass hydrolyzing enzyme cocktail. Penicillium janthinellum NCIM1366 was reported as a cellulase hyper producer and a potential alternative to T. reesei, but a comparison of their hydrolytic performance was seldom attempted. Results Hydrolysis of acid or alkali-pretreated rice straw using cellulase enzyme preparations from P. janthinellum and T. reesei indicated 37 and 43% higher glucose release, respectively, with P. janthinellum enzymes. A comparison of these fungi with respect to their secreted enzymes indicated that the crude enzyme preparation from P. janthinellum showed 28% higher overall cellulase activity. It also had an exceptional tenfold higher beta-glucosidase activity compared to that of T. reesei, leading to a lower cellobiose accumulation and thus alleviating the feedback inhibition. P. janthinellum secreted more number of proteins to the extracellular medium whose total concentration was 1.8-fold higher than T. reesei. Secretome analyses of the two fungi revealed higher number of CAZymes and a higher relative abundance of cellulases upon cellulose induction in the fungus. Conclusions The results revealed the ability of P. janthinellum for efficient biomass degradation through hyper cellulase production, and it outperformed the established industrial cellulase producer T. reesei in the hydrolysis experiments. A higher level of induction, larger number of secreted CAZymes and a high relative proportion of BGL to cellulases indicate the possible reasons for its performance advantage in biomass hydrolysis.

Proteases have long been the target of many drugs, but their potential as therapeutic agents is a well-known, but under-explored area. Due to the heightened threat from new and emerging infectious agents, it is worthwhile to tap into the vast microbial protease resource to identify potential therapeutics. By docking proteases of the fungus Penicillium janthinellum NCIM 1366 with the proteins encoded by the SARS-CoV-2 virus, the enzymes that have the potential to bind with, and thereby degrade viral proteins were identified. In-silico docking analysis revealed that both fungal and commercially available proteases belonging to the A1A, M20A, S10, S8A and T1A families were able to bind the viral spike, envelope, ORF-7a and Nsp2 proteins (binding energy < −50 kJ/mol), thereby opening up the possibility of developing additional therapeutic applications for these enzymes.