Development of Photoaffinity Probe for the Discovery of Steviol Glycosides Biosynthesis Pathway in <i>Stevia rebuadiana</i> and Rapid Substrate Screening
responsible for the biosynthesis pathway coded for the genes is ongoing, and the unknown functional diversity of this class of enzymes has been revealed by genome sequencing. Commonly, it is feasible in annotating of biosyntheticgenes of prokaryotes due to the existence of geneclusters of secondary metabolites. However, in eukaryotes, the biosyntheticgenes are not compactly clustered in the way of prokaryotes
ApUGT, a diterpene glycosyltransferase from Andrographis paniculata, could transfer a glucose to the C-19 hydroxyl moiety of andrograpanin to form neoandrographolide. This glycosyltransferase has a broad substrate scope, and it can glycosylate 26 natural and unnatural compounds of different structural types. This study provides a basis for exploring the glycosylation mechanism of ent-labdane-type diterpenes and plays an important role in diversifying the structures used in drug discovery.
[EN] REBAUDIOSIDE A DERIVATIVE PRODUCTS AND METHODS FOR MAKING<br/>[FR] PRODUITS DÉRIVÉS DU REBAUDIOSIDE A ET PROCÉDÉS DE FABRICATION ASSOCIÉS
申请人:COCA COLA CO
公开号:WO2009108680A3
公开(公告)日:2009-12-03
A complete specific cleavage of glucosyl and ester linkages of stevioside for preparing steviol with a β-galactosidase from Sulfolobus solfataricus
作者:Jun-Ming Chen、Yong-mei Xia、Hui-da Wan、Hai-jun Wang、Xiang Liu
DOI:10.1016/j.molcatb.2014.03.011
日期:2014.7
beta-Galactosidases from Sulfolobus solfataricus have been used to synthesize galactooligosaccharide and lactulose. In this work, a beta-galactosidase from S. solfataricus with weak beta-glucosidase activity but high lipase activity was employed as catalyst to assist hydrolysis of stevioside to obtain steviol, an important starting reagent of synthetic bioactive materials and the main metablite of stevioside in human digistion. The beta-galactosidase presented a strict substrate specifity on converting stevioside to steviol in a stoichiometric yield. The beta-galactosidase favors the cleavage of glycoside linkages prior to cleavage of glycosyl ester linkage. The hydrolysis is external diffusion controlled and hence has to bear low substrate concentration in regular process, but this can be solved with product removal or enzyme immobilization. The immobilization of the beta-galactosidase onto cross-linked chitosan microspheres did not enhance the enzyme's thermal or pH stability but eliminated the external diffusion, and therefore speeded the hydrolysis in 3 folds. The relative reaction activity dropped only 1.75% after 6 runs of using the immobilized beta-galactosidase. (c) 2014 Elsevier B.V. All rights reserved.
[EN] PRODUCTION OF STEVIOL GLYCOSIDES IN RECOMBINANT HOSTS<br/>[FR] PRODUCTION DE GLYCOSIDES DE STÉVIOL DANS DES HÔTES DE RECOMBINAISON
申请人:EVOLVA SA
公开号:WO2016120486A1
公开(公告)日:2016-08-04
The invention relates to recombinant microorganisms and methods for producing steviol glycosides, glycosylated ent-kaurenol, and glycosylated ent-kaurenoic acid.