title: Biosynthesis of (+)-catechin glycosides using recombinant amylosucrase from Deinococcus geothermalis DSM 11300.
abstract: Amylosucrase (ASase, EC 2.4.1.4) is a glucosyltransferase that hydrolyzes sucrose into glucose and fructose and produces amylose-like glucan polymers from the released glucose. (+)-Catechin is a plant polyphenolic metabolite having skin-whitening and antioxidant activities. In this study, the ASase gene from Deinococcus geothermalis (dgas) was expressed in Escherichia coli, while the recombinant DGAS enzyme was purified using a glutathione S-transferase fusion system. The (+)-catechin glycoside derivatives were synthesized from (+)-catechin using DGAS transglycosylation activity. We confirmed the presence of two major transglycosylation products using TLC. The (+)-catechin transglycosylation products were isolated using silica gel open column chromatography and recycling-HPLC. Two (+)-catechin major transfer products were determined through (1)H and (13)C NMR to be (+)-catechin-3'-O-α-D-glucopyranoside with a glucose molecule linked to (+)-catechin and (+)-catechin-3'-O-α-D-maltoside with a maltose linked to (+)-catechin. The presence of (+)-catechin maltooligosaccharides in the DGAS reaction was also confirmed via recycling-HPLC and enzymatic analysis. The effects of various reaction conditions (temperature, enzyme concentration, and molar ratio of acceptor and donor) on the yield and type of (+)-catechin glycosides were investigated.
authors: Graduate School of Biotechnology and Institute of Life Sciences & Resources, Kyung Hee University, Yongin 446-701, Republic of Korea.
authors: Hyun-Kug
authors: HK
authors: Cho
authors: Hee-Hang
authors: HH
authors: Kim
authors: Dong-Ho
authors: DH
authors: Seo
authors: Jong-Hyun
authors: JH
authors: Jung
authors: Ji-Hae
authors: JH
authors: Park
authors: Nam-In
authors: NI
authors: Baek
authors: Myo-Jeong
authors: MJ
authors: Kim
authors: Sang-Ho
authors: SH
authors: Yoo
authors: Jaeho
authors: J
authors: Cha
authors: Young-Rok
authors: YR
authors: Kim
authors: Cheon-Seok
authors: CS
authors: Park
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002392:Catechin / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D034301:Deinococcus / Q000201:enzymology* / Q000235:genetics; D005964:Glucosyltransferases / Q000235:genetics / Q000378:metabolism*; D006027:Glycosides / Q000096:biosynthesis* / Q000737:chemistry; D006031:Glycosylation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013395:Sucrose / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D006027:Glycosides; D011994:Recombinant Proteins; D013395:Sucrose; D002392:Catechin; D005964:Glucosyltransferases; C019700:amylosucrase