Xylanase and beta-xylosidase from Penicillium janczewskii: Purification, characterization and hydrolysis of substrates

Author(s)

Fanchini Terrasan, Cesar Rafael ; Manuel Guisan, Jose ; Carmona, Eleonora Cano

• Document type: Journal article
• Source: ELECTRONIC JOURNAL OF BIOTECHNOLOGY; v. 23, p. 54-62, SEP 2016.
• Web of Science Citations: 12

Abstract

Background: Xylanases and beta-D-xylosidases are the most important enzymes responsible for the degradation of xylan, the second main constituent of plant cell walls. Results: In this study, the main extracellular xylanase (XYL I) and beta-xylosidase (BXYL I) from the fungus Penicillium janczewskii were purified, characterized and applied for the hydrolysis of different substrates. Their molecular weights under denaturing and non-denaturing conditions were, respectively, 30.4 and 23.6 kDa for XYL I, and 100 and 200 kDa for BXYL I, indicating that the latter is homodimeric. XYL I is highly glycosylated (78%) with optimal activity in pH 6.0 at 65 degrees C, while BXYL I presented lower sugar content (10.5%) and optimal activity in pH 5.0 at 75 degrees C. The half-lives of XYL I at 55, 60 and 65 degrees C were 125, 16 and 6 min, respectively. At 60 degrees C, BXYL I retained almost 100% of the activity after 6 h. NH4+, Na+, DTT and beta-mercaptoethanol stimulated XYL I, while activation of BXYL I was not observed. Interestingly, XYL I was only partially inhibited by Hg2+, while BXYL I was completely inhibited. Xylobiose, xylotriose and larger xylooligosaccharides were the main products from xylan hydrolysis by XYL I. BXYL I hydrolyzed xylobiose and larger xylooligosaccharides with no activity against xylans. Conclusion: The enzymes act synergistically in the degradation of xylans, and present industrial characteristics especially in relation to optimal activity at high temperatures, prolonged stability of BXYL I at 60 degrees C, and stability of XYL I in wide pH range. (C) 2016 Pontificia Universidad Catolica de Valparaiso. Production and hosting by Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 07/08640-8 - Xylanases, b-xylosidases from Penicillium janczewskii: purification, characterization and application in cellulosic pulp bleaching and for animal feed
• Grantee: César Rafael Fanchini Terrasan
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 10/16582-0 - Purification, properties and application of xylanolytic enzymes produced by Penicillium janczewskii
• Grantee: Eleonora Cano Carmona
• Support Opportunities: Regular Research Grants