Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Agriculture / Faculty of Agriculture >
Peer-reviewed Journal Articles, etc >
Engineered dextranase from Streptococcus mutans enhances the production of longer isomaltooligosaccharides
Title: | Engineered dextranase from Streptococcus mutans enhances the production of longer isomaltooligosaccharides |
Authors: | Klahan, Patcharapa Browse this author | Okuyama, Masayuki Browse this author →KAKEN DB | Jinnai, Kohei Browse this author | Ma, Min Browse this author | Kikuchi, Asako Browse this author | Kumagai, Yuya Browse this author →KAKEN DB | Tagami, Takayoshi Browse this author | Kimura, Atsuo Browse this author →KAKEN DB |
Keywords: | Glycoside hydrolase family 66 | dextranase | isomaltooligosaccharides | bond cleavage frequency |
Issue Date: | Sep-2018 |
Publisher: | Taylor & Francis |
Journal Title: | Bioscience biotechnology and biochemistry |
Volume: | 82 |
Issue: | 9 |
Start Page: | 1480 |
End Page: | 1487 |
Publisher DOI: | 10.1080/09168451.2018.1473026 |
PMID: | 29806555 |
Abstract: | Herein, we investigated enzymatic properties and reaction specificities of Streptococcus mutans dextranase, which hydrolyzes α-(1→6)-glucosidic linkages in dextran to produce isomaltooligosaccharides. Reaction specificities of wild-type dextranase and its mutant derivatives were examined using dextran and a series of enzymatically prepared p-nitrophenyl α-isomaltooligosaccharides. In experiments with 4-mg·mL⁻¹ dextran, isomaltooligosaccharides with degrees of polymerization (DP) of 3 and 4 were present at the beginning of the reaction, and glucose and isomaltose were produced by the end of the reaction. Increased concentrations of the substrate dextran (40 mg·mL⁻¹) yielded isomaltooligosaccharides with higher DP, and the mutations T558H, W279A/T563N, and W279F/T563N at the -3 and -4 subsites affected hydrolytic activities of the enzyme, likely reflecting decreases in substrate affinity at the -4 subsite. In particular, T558H increased the proportion of isomaltooligosaccharide with DP of 5 in hydrolysates following reactions with 4-mg·mL⁻¹ dextran.Abbreviations CI: cycloisomaltooligosaccharide; CITase: CI glucanotransferase; CITase-Bc: CITase from Bacillus circulans T-3040; DP: degree of polymerization of glucose unit; GH: glycoside hydrolase family; GTF: glucansucrase; HPAEC-PAD: high performance anion-exchange chromatography-pulsed amperometric detection; IG: isomaltooligosaccharide; IGn: IG with DP of n (n, 2‒5); PNP: p-nitrophenol; PNP-Glc: p-nitrophenyl α-glucoside; PNP-IG: p-nitrophenyl isomaltooligosaccharide; PNP-IGn: PNP-IG with DP of n (n, 2‒6); SmDex: dextranase from Streptococcus mutans; SmDexTM: S. mutans ATCC25175 SmDex bearing Gln100‒Ile732. |
Rights: | This is an Accepted Manuscript of an article published by Taylor & Francis in Bioscience biotechnology and biochemistry on 26/05/2018, available online: http://www.tandfonline.com/10.1080/09168451.2018.1473026. |
Type: | article (author version) |
URI: | http://hdl.handle.net/2115/74378 |
Appears in Collections: | 農学院・農学研究院 (Graduate School of Agriculture / Faculty of Agriculture) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
|
Submitter: 奥山 正幸
|