title: Characterization of a thermostable endo-1,3(4)-β-glucanase from Caldicellulosiruptor sp. strain F32 and its application for yeast lysis.
abstract: β-1,3-Glucans, important structural components of cell wall or nutritional components of the endosperm, are extensively found in bacteria, fungi, yeast, algae, and plants. The structural complexity of β-1,3-glucans implies that the enzymatic depolymerization of polysaccharides needs combined activities of distinct enzymes. In this study, Lam16A-GH, the catalytic module of a putative glycoside hydrolase (GH) family 16 laminarinase/lichenase from thermophilic bacterium Caldicellulosiruptor sp. F32, was purified and characterized through heterologous expression in Escherichia coli. Lam16A-GH can hydrolyze both β-1,3-glucan (laminarin) and β-1,3-1,4-glucan (barley β-glucan) revealed by analysis of the products of polysaccharide degradation using thin-layer chromatography (TLC). The time required for the loss of 50 % of its activity is 45 h under the optimal condition of 75 °C and pH 6.5. Oligosaccharides degradation assay indicated that Lam16A-GH can catalyze endo-hydrolysis of the β-1,4 glycosidic linkage adjacent to a 3-O-substituted glucosyl residue in the mixed linked β-glucans, as well as the β-1,3 linkage. The survival rate of Saccharomyces cerevisiae cells depends on the addition of Lam16A-GH, and the cytoplasm protein was released from the apparently deconstructed yeast cells. These results indicate that the bi-functional thermostable Lam16A-GH exhibits unique enzymatic properties and potential for yeast lysis.
authors.affiliation: Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China.
authors.forename: Dong-Dong
authors.initials: DD
authors.lastname: Meng
authors.affiliation: Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
authors.affiliation: Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China.
authors.forename: Xiao-Qing
authors.initials: XQ
authors.lastname: Ma
authors.affiliation: Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China.
authors.forename: Shi-Qi
authors.initials: SQ
authors.lastname: Ji
authors.affiliation: Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Lu
authors.affiliation: Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China. lifl@qibebt.ac.cn.
authors.forename: Fu-Li
authors.initials: FL
authors.lastname: Li
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002473:Cell Wall / Q000737:chemistry; D002855:Chromatography, Thin Layer; D003001:Cloning, Molecular; D044644:Endo-1,3(4)-beta-Glucanase / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005936:Glucans / Q000737:chemistry; D006026:Glycoside Hydrolases / Q000235:genetics / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D009844:Oligosaccharides / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000166:cytology*; D013379:Substrate Specificity; D013696:Temperature; D046950:Thermoanaerobacterium / Q000201:enzymology* / Q000235:genetics; D015854:Up-Regulation; D047071:beta-Glucans / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D005936:Glucans; D009844:Oligosaccharides; D047071:beta-Glucans; C040088:1,4-glucan; C033363:beta-1,3-glucan; D006026:Glycoside Hydrolases; D044644:Endo-1,3(4)-beta-Glucanase; C028020:licheninase
keywords: Caldicellulosiruptor; Endo-1,3(4)-β-glucanase; Glycoside hydrolase; Thermostable; Yeast lysis