The family 22 carbohydrate-binding module of bifunctional xylanase/β-glucanase Xyn10E from Paenibacillus curdlanolyticus B-6 has an important role in lignocellulose degradation

Journal article

Authors/Editors

Strategic Research Themes

No matching items found.

Publication Details

Author list: Sermsathanaswadi J., Baramee S., Tachaapaikoon C., Pason P., Ratanakhanokchai K., Kosugi A.

Publisher: Elsevier

Publication year: 2017

Journal: Enzyme and Microbial Technology (0141-0229)

Volume number: 96

Start page: 75

End page: 84

Number of pages: 10

ISSN: 0141-0229

eISSN: 1879-0909

URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84990866300&doi=10.1016%2fj.enzmictec.2016.09.015&partnerID=40&md5=8eb9132e752598cfd8babbb41dab3baf

Languages: English-Great Britain (EN-GB)

View in Web of Science | View on publisher site | View citing articles in Web of Science

Abstract

A newly isolated endo-β-1,4-xylanase (Xyn10E) from Paenibacillus curdlanolyticus B-6 has a modular structure consisting of a family 22 carbohydrate-binding module (CBM), a glycoside hydrolase (GH) family 10 catalytic domain, two fibronectin type III (Fn3) domains, and a family 3 CBM at the C-terminus. Intact Xyn10E (rXyn10E), CBM22-deleted Xyn10E (X-CBM3), CBM3-deleted Xyn10E (X-CBM22), and GH10 catalytic domain only (X-GH10) were expressed in Escherichia coli. rXyn10E showed bifunctional degradation activity toward xylan and β-glucan and also degraded microcrystalline cellulose. Although X-CBM3 and X-GH10 had drastically reduced xylanase and β-glucanase activities, X-CBM22 mostly retained these activities. Similar Km values were obtained for rXyn10E and X-CBM3, but kcat and kcat/Km values for X-CBM3 and X-GH10 were lower than those for rXyn10E, suggesting that CBM22 of Xyn10E may contribute to catalytic efficiency. In binding assays, X-CBM3 was still able to bind to β-glucan, soluble xylan, insoluble xylan, and cellulose through GH10 and CBM3. These results indicate that CBM22 has an important role not only in binding to xylan and β-glucan but also in feeding both polysaccharides into the neighboring GH10 catalytic domain. rXyn10E showed remarkable synergism with rXyn11A, a major xylanase subunit of P. curdlanolyticus B-6, in the degradation of untreated corn stover and sugarcane bagasse; however, the combination of X-CBM3 and rXyn11A was not synergistic. These results indicate that Xyn10E and Xyn11A act synergistically on lignocellulosic biomass, and CBM22 is essential for efficient degradation of lignocellulosic materials. © 2016 Elsevier Inc.

Keywords

β-Glucanase