An Acidic Thermostable Recombinant Aspergillus nidulans Endoglucanase Is Active towards Distinct Agriculture Residues.
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 K m = 27.5 ± 4.33 mg/mL, V max = 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.
Department of Cellular Biology, Institute of Biological Sciences, University of Brasilia, 70.910-900 Brasilia, DF, Brazil.
Eveline Queiroz de Pinho
EQ
Tavares
Marciano Regis
MR
Rubini
Thiago Machado
TM
Mello-de-Sousa
Gilvan Caetano
GC
Duarte
Fabrícia Paula
FP
de Faria
Edivaldo Ximenes
EX
Ferreira Filho
Cynthia Maria
CM
Kyaw
Ildinete
I
Silva-Pereira
Marcio Jose
MJ
Poças-Fonseca