Cloning and expression of two genes coding endo-β-1,4-glucanases from Trichoderma asperellum PQ34 in Pichia pastoris

Two genes coding emlo-beta-1,TglucallaSCS were cloned In tin l'rich.oderma asperellun. PQ34 wh ch was isolated from Thua Thien Hue province, Vietnam. The expression of these genes in Pichia pastoris produced two enzymes with molecular masses of approximately 46 klla (about 42 klla enzyme and 4 kDa of signal peptide). The effects of induction tirne and temperature, inducer concentration, and culture medium on the endo-,3-1,4-glucanase activity were investigated. The results showed that the highest total activities 01 two endo-beta-1,4-gbicanases were approximately 4.7 x 10(-8) kat (from Glul-TA gene) and 7.3 x 10(-8) kat (from Glu2-TA gene) occurred after 4 days of induction using, 25 mL L-1 methanol at 30 degrees C when the yeast cells were cultured in a YPL medium (C) 2015 Institute of Chemistry, Slovak Academy of Sciences