title: Enzymatic properties of β-1,3-glucanase from Streptomyces sp Mo.
abstract: Streptomyces sp Mo endo-β-1,3-glucanase was found to have hydrolyzing activity toward curdlan and released laminarioligosaccharides selectively. The molecular weight was estimated to be 36000 Da and its N-terminal amino acid sequence was VTPPDISVTN. The optimal pH was 6 and the enzyme was found to be stable from pH 5 to 8. The optimal temperature was 60 °C and the activity was stable below 50 °C. The enzyme hydrolyzed selectively curdlan containing only β-1,3 linkages. The enzyme had 89% relative activity toward Laminaria digitata laminarin, which contains a small amount of β-1,6 linkages compared with curdlan, while Eisenia bicyclis laminarin with a higher amount of β-1,6-linkages, was not hydrolyzed. Mo enzyme adsorbed completely on curdlan powder. The enzymatic hydrolysis of curdlan powder resulted in the accumulation of laminaribiose (yield 81.7%). Trisaccharide was inevitably released from the hydrolysis of laminarioligosaccharides with 5 to 7 degrees of polymerization (DP). Although the enzyme cleaved off disaccharide (DP 2) from tetrasaccharide (DP 4), the reaction rate was lower than those of DP 5 to 7. The results indicated that the active site of Mo endo-β-1,3-glucanase can efficiently recognize glucosyl residue chain of greater than DP 5 and hydrolyzes the β-1,3 linkage between the 3rd and 4th glucosyl residue.
authors.affiliation: Department of Life and Nutritional Science, Fukuyama University, Fukuyama, Hiroshima, Japan. kurakake@fubac.fukuyama-u.ac.jp
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kurakake
authors.forename: Yuuki
authors.initials: Y
authors.lastname: Yamanouchi
authors.forename: Kouta
authors.initials: K
authors.lastname: Kinohara
authors.forename: Shingo
authors.initials: S
authors.lastname: Moriyama
mesh_terms: D004269:DNA, Bacterial / Q000235:genetics; D004187:Disaccharides / Q000737:chemistry; D004693:Glucan Endo-1,3-beta-D-Glucosidase / Q000737:chemistry*; D005936:Glucans; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008970:Molecular Weight; D011134:Polysaccharides / Q000737:chemistry; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013302:Streptomyces / Q000201:enzymology* / Q000235:genetics; D013379:Substrate Specificity; D013696:Temperature; D047071:beta-Glucans / Q000737:chemistry
chemical_list: D004269:DNA, Bacterial; D004187:Disaccharides; D005936:Glucans; D011134:Polysaccharides; D012336:RNA, Ribosomal, 16S; D047071:beta-Glucans; C014637:laminaribiose; C038459:curdlan; C008247:laminaran; D004693:Glucan Endo-1,3-beta-D-Glucosidase