title: In vitro synthesis of linear α-1,3-glucan and chemical modification to ester derivatives exhibiting outstanding thermal properties.
abstract: Bio-based polymer is considered as one of potentially renewable materials to reduce the consumption of petroleum resources. We report herein on the one-pot synthesis and development of unnatural-type bio-based polysaccharide, α-1,3-glucan. The synthesis can be achieved by in vitro enzymatic polymerization with GtfJ enzyme, one type of glucosyltransferase, cloned from Streptococcus salivarius ATCC 25975 utilizing sucrose, a renewable feedstock, as a glucose monomer source, via environmentally friendly one-pot water-based reaction. The structure of α-1,3-glucan is completely linear without branches with weight-average molecular weight (Mw) of 700 kDa. Furthermore, acetate and propionate esters of α-1,3-glucan were synthesized and characterized. Interestingly, α-1,3-glucan acetate showed a comparatively high melting temperature at 339 °C, higher than that of commercially available thermoplastics such as PET (265 °C) and Nylon 6 (220 °C). Thus, the discovery of crystalline α-1,3-glucan esters without branches with high thermal stability and melting temperature opens the gate for further researches in the application of thermoplastic materials.
authors.affiliation: Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Sakarin
authors.initials: S
authors.lastname: Puanglek
authors.affiliation: Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kimura
authors.affiliation: Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Enomoto-Rogers
authors.affiliation: Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.|Materials Structure Group 1, Research &Utilization Division, Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan.
authors.forename: Taizo
authors.initials: T
authors.lastname: Kabe
authors.affiliation: Department of Environmental and Natural Resource Sciences, Tokyo University of Agriculture and Technology, 3-8-1 Harumi-cho, Fuchu-shi, Tokyo, 183-8509, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Yoshida
authors.affiliation: Department of Forest and Biomaterials Science, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 60608502, Japan.|Department of Plant &Environmental New Resources, College of Life Sciences, Kyung Hee University, 1, Seocheon-dong, Giheung-ku, Yongin-si, Gyeonggi-do, 446-701, Korea.
authors.forename: Masahisa
authors.initials: M
authors.lastname: Wada
authors.affiliation: Department of Biomaterial Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Tadahisa
authors.initials: T
authors.lastname: Iwata
mesh_terms: D066241:Carbon-13 Magnetic Resonance Spectroscopy; D004952:Esters / Q000138:chemical synthesis / Q000737:chemistry*; D005936:Glucans / Q000138:chemical synthesis* / Q000737:chemistry*; D005964:Glucosyltransferases / Q000378:metabolism; D008970:Molecular Weight; D066244:Proton Magnetic Resonance Spectroscopy; D013291:Streptococcus / Q000201:enzymology; D013696:Temperature; D044366:Transition Temperature
chemical_list: D004952:Esters; D005936:Glucans; C045788:alpha-1,3-glucan; D005964:Glucosyltransferases