title: The first bacterial β-1,6-endoglucanase from Saccharophagus degradans 2-40Tfor the hydrolysis of pustulan and laminarin.
abstract: β-1,6-glucan is a polysaccharide found in brown macroalgae and fungal cell walls. In this study, a β-1,6-endoglucanase gene from Saccharophagus degradans 2-40T, gly30B, was cloned and overexpressed in Escherichia coli. Gly30B, which belongs to the glycoside hydrolase family 30 (GH30), was found to possess β-1,6-endoglucanase activity by hydrolyzing β-1,6-glycosidic linkages of pustulan (β-1,6-glucan derived from fungal cell walls) and laminarin (β-1,3-glucan with β-1,6-branchings, derived from brown macroalgae) to produce gentiobiose and glucose as the final products. The optimal pH and temperature for Gly30B activity were found to be pH 7.0 and 40 °C, respectively. The kinetic constants of Gly30B, Vmax, KM, and kcatwere determined to be 153.8 U/mg protein, 24.2 g/L, and 135.6 s-1for pustulan and 32.8 U/mg protein, 100.8 g/L, and 28.9 s-1for laminarin, respectively. To our knowledge, Gly30B is the first β-1,6-endoglucanase characterized from bacteria. Gly30B can be used to hydrolyze β-1,6-glucans of brown algae or fungal cell walls for producing gentiobiose as a high-value sugar and glucose as a fermentable sugar.
authors: Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea.
authors: Damao
authors: D
authors: Wang
authors: Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea.
authors: Do Hyoung
authors: DH
authors: Kim
authors: Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea.
authors: Eun Ju
authors: EJ
authors: Yun
authors: Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul, 02707, South Korea.
authors: Yong-Cheol
authors: YC
authors: Park
authors: Department of Agricultural Biotechnology, Seoul National University, Seoul, 08826, South Korea.
authors: Jin-Ho
authors: JH
authors: Seo
authors: Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea. khekim@korea.ac.kr.
authors: Kyoung Heon
authors: http://orcid.org/0000-0003-4600-8668
authors: KH
authors: Kim
mesh_terms: D002480:Cellulase / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D003001:Cloning, Molecular; D004187:Disaccharides / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D020563:Gammaproteobacteria / Q000201:enzymology* / Q000235:genetics; D015870:Gene Expression; D005936:Glucans / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D000459:Phaeophyceae; D011134:Polysaccharides / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D013696:Temperature
chemical_list: D004187:Disaccharides; D005936:Glucans; D011134:Polysaccharides; D011994:Recombinant Proteins; C002076:pustulan; C008247:laminaran; D002480:Cellulase; C100052:gentiobiose; D005947:Glucose
keywords: GH30; Hydrolysis; Saccharophagus degradans 2-40T; β-1,6-endoglucanase