Properties of hemicellulases of the enzyme complex from Trichoderma longibrachiatum

• Published in: Applied biochemistry and microbiology Vol. 42; no. 6; pp. 573 - 583
• Main Authors: Markov, A V, Gusakov, A V, Dzedzyulya, E I, Ustinov, B B, Antonov, A A, Okunev, ON, Bekkarevich, A O, Sinitsyn, AP
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01.12.2006
• Subjects: Enzymes; Hypocrea jecorina; Microbiology; Trichoderma longibrachiatum
• ISSN: 0003-6838; 1608-3024
• DOI: 10.1134/S000368380606007X

Six xylan-hydrolyzing enzymes have been isolated from the preparations Celloviridin G20x and Xybeten-Xyl, obtained earlier based on the strain 1 Trichoderma longibrachiatum (Trichoderma reesei) TW-1. The enzymes isolated were represented by three xylanases (XYLs), XYL I (20 kDa, pI 5.5), XYL II (21 kDa, pI 9.5), XYL III (30 kDa, pI 9.1); endoglucanase I (EG I), an enzyme exhibiting xylanase activity (57 kDa, pI 4.6); and two exodepolymerases, β-xylosidase (β-XYL; 80 kDa, pI 4.5) and α-L-arabinofuranosidase I (α-L-AF I; 55 kDa, pI 7.4). The substrate specificity of the enzymes isolated was determined. XYL II exhibited maximum specific xylanase activity (190 U/mg). The content of the enzymes in the preparation was assessed. Maximum contributions to the total xylanase activities of preparations Celloviridin G20x and Xybeten-Xyl were made by EG I and XYL II, respectively. Effects of temperature and pH on the enzyme activities, their stabilities under various conditions, and the kinetics of exhaustive hydrolysis of glucuronoxylan and arabinoxylan were studied. Combinations of endodepolymerases (XYL I, XYL II, XYL III, or EG I) and exodepolymerases (α-L-AF I or β-XYL) produced synergistic effects on arabinoxylan cleavage. The reverse was the case when endodepolymerases, such as XYL I or EG I, were combined with α-L-AF I.[PUBLICATION ABSTRACT]