An Acidic Thermostable Recombinant Aspergillus nidulans Endoglucanase Is Active towards Distinct Agriculture Residues

Abstract EN

Aspergillus nidulans is poorly exploited as a source of enzymes for lignocellulosic residues degradation for biotechnological purposes.

This work describes the A.

nidulans Endoglucanase A heterologous expression in Pichia pastoris, the purification and biochemical characterization of the recombinant enzyme.

Active recombinant endoglucanase A (rEG A) was efficiently secreted as a 35 kDa protein which was purified through a two-step chromatography procedure.

The highest enzyme activity was detected at 50°C/pH 4.

rEG A retained 100% of activity when incubated at 45 and 55°C for 72 h.

Purified rEG A kinetic parameters towards CMC were determined as Km=27.5±4.33 mg/mL, Vmax=1.185±0.11 mmol/min, and 55.8 IU (international units)/mg specific activity.

Recombinant P.

pastoris supernatant presented hydrolytic activity towards lignocellulosic residues such as banana stalk, sugarcane bagasse, soybean residues, and corn straw.

These data indicate that rEG A is suitable for plant biomass conversion into products of commercial importance, such as second-generation fuel ethanol.