title: Increased yield of β-glucosidase-catalyzed hydrolysis reactions in the presence of betaine-type metabolite analog.
abstract: β-Glucosidases (EC 3.2.1.21), abundant enzymes distributed in animals, plants and microorganism, has been generating lots of attentions for bioethanol production from cellulosic biomass. In this study, using three different origins of β-glucosidases, glucose productivity of β-glucosidase-catalyzed hydrolysis reactions in the presence of synthetic betaine-type metabolite analog (2-N,N,N-tri-n-butylammonium) acetate, was investigated. By the addition of the analog, the hydrolysis yields for all β-glucosidases was highly improved from 4-13 to 64-100 %. To understand the factors affecting on the yield enhancements, the kinetic parameters, inhibition constants of end-product and temporal stability of β-glucosidases were compared. As a result, enhancement of the yields is mainly related to the increase in the temporal stability of β-glucosidases in the presence of the analog. The present findings lead to not only improve the glucose productivity of β-glucosidase-catalyzed hydrolysis reaction toward bioethanol production but also apply to a new stabilization method for various unstable enzymes.
authors.affiliation: Department of Nanobiochemistry, FIRST (Frontiers of Innovative Research in Science and Technology), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan.
authors.forename: Shiro
authors.initials: S
authors.lastname: Sehata
authors.affiliation: Department of Nanobiochemistry, FIRST (Frontiers of Innovative Research in Science and Technology), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan.
authors.forename: Ryojun
authors.initials: R
authors.lastname: Suzuki
authors.affiliation: Department of Nanobiochemistry, FIRST (Frontiers of Innovative Research in Science and Technology), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan. koumoto@center.konan-u.ac.jp.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Koumoto
mesh_terms: D060054:Agrobacterium / Q000201:enzymology*; D001426:Bacterial Proteins / Q000737:chemistry*; D001622:Betaine / Q000737:chemistry*; D002482:Cellulose / Q000737:chemistry; D005947:Glucose / Q000737:chemistry; D010940:Plant Proteins / Q000737:chemistry*; D000068181:Prunus dulcis / Q000201:enzymology*; D020124:Thermotoga maritima / Q000201:enzymology*; D001617:beta-Glucosidase / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D010940:Plant Proteins; D001622:Betaine; D002482:Cellulose; D001617:beta-Glucosidase; D005947:Glucose
keywords: Betaine-type cellular metabolite; Glucose productivity; Metabolite analog; Temporal stabilization; β-Glucosidase