Cloning of novel bacterial xylanases from lignocellulose-enriched compost metagenomic libraries

AMB Express

Lars Paulin¹  Simo Ellilä²  Mari Nyyssönen²  Merja Itävaara²  Anu Koivula²  Paul Bromann²  Kristiina Kruus² 

[1] Institute of Biotechnology, University of Helsinki;VTT Technical Research Centre of Finland;

关键词: Xylanase;    Metagenomics;    Lignocellulose;    Compost;    Screening;    Cloning;   

DOI  :  10.1186/s13568-019-0847-9

来源: DOAJ

【 摘 要 】

Abstract Xylanases are in important class of industrial enzymes that are essential for the complete hydrolysis of lignocellulosic biomass into fermentable sugars. In the present study, we report the cloning of novel xylanases with interesting properties from compost metagenomics libraries. Controlled composting of lignocellulosic materials was used to enrich the microbial population in lignocellulolytic organisms. DNA extracted from the compost samples was used to construct metagenomics libraries, which were screened for xylanase activity. In total, 40 clones exhibiting xylanase activity were identified and the thermostability of the discovered xylanases was assayed directly from the library clones. Five genes, including one belonging to the more rare family GH8, were selected for subcloning and the enzymes were expressed in recombinant form in E. coli. Preliminary characterization of the metagenome-derived xylanases revealed interesting properties of the novel enzymes, such as high thermostability and specific activity, and differences in hydrolysis profiles. One enzyme was found to perform better than a standard Trichoderma reesei xylanase in the hydrolysis of lignocellulose at elevated temperatures.

【 授权许可】

Unknown