Evaluation of secretome of highly efficient lignocellulolytic Penicillium sp. Dal 5 isolated from rhizosphere of conifers

Abstract

Penicillium sp. (Dal 5) isolated from rhizosphere of conifers from Dalhousie (Himachal Pradesh, India) was found to be an efficient cellulolytic strain. The culture under shake flask on CWR (cellulose, wheat bran and rice straw) medium produced appreciably higher levels of endoglucanase (35.69U/ml), β-glucosidase (4.20U/ml), cellobiohydrolase (2.86U/ml), FPase (1.2U/ml) and xylanase (115U/ml) compared to other Penicillium strains reported in literature. The mass spectroscopy analysis of Penicillium sp. Dal 5 secretome identified 108 proteins constituting an array of CAZymes including glycosyl hydrolases (GH) belonging to 24 different families, polysaccharide lyases (PL), carbohydrate esterases (CE), lytic polysaccharide mono-oxygenases (LPMO) in addition to swollenin and a variety of carbohydrate binding modules (CBM) indicating an elaborate genetic potential of this strain for hydrolysis of lignocellulosics. Further, the culture extract was evaluated for hydrolysis of alkali treated rice straw, wheat straw, bagasse and corn cob at 10% substrate loading rate.

Keywords: Carbohydrate binding modules; Exo-proteome; Glycosyl hydrolases; Hydrolysis; Penicillium sp. Dal 5.