title: Purification, characterization and function analysis of an extracellular β-glucosidase from elongating stipe cell walls in Coprinopsis cinerea.
abstract: A β-glycoside hydrolase was isolated from cell walls material in Coprinopsis cinerea elongating stipes. By analysis of SDS-PAGE, MALDI-TOF/TOF MS and substrate specificity, this enzyme was characterized as an extracellular β-glucosidase which is a trimer consisting of three homosubunits. β-Glucosidase did not degrade β-glucans with modified ends, whereas it hydrolyzed various β-glucans with free ends and related oligosaccharides with β-1,3-, β-1,4- or β-1,6-linkages. Although this β-glucosidase possesses glycosyltransferase activity on laminarioligosaccharides, it did not transfer glucose residues from laminaritriose to β-glucan in stipe cell walls to produce larger β-glucan molecules; instead, it caused a decrease in the molecular size of stipe wall β-glucan by removing glucose. Relatively, the molecular size of wall β-glucans in the elongating apical stipe was less than that found in the non-elongating basal stipes, and this β-glucosidase was more highly expressed in the elongating apical stipe than in non-elongating basal regions. Therefore, we propose that β-glucosidase functions by trimming or cutting the β-glucan side chains on the β-1,3-glucan backbone to prevent them from forming longer branches, keeping the wall plastic to promote diffuse wall growth.
authors.affiliation: Jiangsu Key Laboratory for Microbes and Microbial Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Science, Nanjing Normal University, Nanjing 210023, PR China zhangwenming206@126.com.
authors.forename: Wenming
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Jiangsu Key Laboratory for Microbes and Microbial Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Science, Nanjing Normal University, Nanjing 210023, PR China.
authors.forename: Liqin
authors.initials: L
authors.lastname: Kang
authors.affiliation: Jiangsu Key Laboratory for Microbes and Microbial Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Science, Nanjing Normal University, Nanjing 210023, PR China.
authors.forename: Mingmei
authors.initials: M
authors.lastname: Yang
authors.affiliation: Jiangsu Key Laboratory for Microbes and Microbial Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Science, Nanjing Normal University, Nanjing 210023, PR China.
authors.forename: Yajun
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Jiangsu Key Laboratory for Microbes and Microbial Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Science, Nanjing Normal University, Nanjing 210023, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.affiliation: Jiangsu Key Laboratory for Microbes and Microbial Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Science, Nanjing Normal University, Nanjing 210023, PR China.
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Jiangsu Key Laboratory for Microbes and Microbial Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Science, Nanjing Normal University, Nanjing 210023, PR China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Yuan
mesh_terms: D000363:Agaricales / Q000166:cytology / Q000201:enzymology* / Q000254:growth & development*; D002473:Cell Wall / Q000201:enzymology / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D016695:Glycosyltransferases; D006868:Hydrolysis; D009844:Oligosaccharides / Q000378:metabolism; D047071:beta-Glucans / Q000737:chemistry / Q000378:metabolism*; D001617:beta-Glucosidase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D009844:Oligosaccharides; D047071:beta-Glucans; C033363:beta-1,3-glucan; D016695:Glycosyltransferases; D001617:beta-Glucosidase
keywords: Coprinopsis cinerea; extracellular β-glucosidase; glycosyltransferase activity; hydrolyase activity; stipe elongation