Crystal Structures of the C-Glycosyltransferase UGT708C1 from Buckwheat Provide Insights into the Mechanism of C-Glycosylation.
Plant Cell
; 32(9): 2917-2931, 2020 09.
Article
en En
| MEDLINE
| ID: mdl-32699169
ABSTRACT
C-Glycosyltransferases (CGTs) catalyze the formation of C-glycosidic bonds for the biosynthesis of C-glycosides, but the underlying mechanism is unclear. This process improves the solubility and bioavailability of specialized metabolites, which play important roles in plant growth and development and represent rich resources for drug discovery. Here, we performed functional and structural studies of the CGT UGT708C1 from buckwheat (Fagopyrum esculentum). Enzymatic analysis showed that UGT708C1 is capable of utilizing both UDP-galactose and UDP-glucose as sugar donors. Our structural studies of UGT708C1 complexed with UDP-glucose and UDP identified the key roles of Asp382, Gln383, Thr151, and Thr150 in recognizing the sugar moiety of the donor substrate and Phe130, Tyr102, and Phe198 in binding and stabilizing the acceptor. A systematic site-directed mutagenesis study confirmed the important roles of these residues. Further structural analysis combined with molecular dynamics simulations revealed that phloretin binds to the acceptor binding pocket in a bent state with a precise spatial disposition and complementarity. These findings provide insights into a catalytic mechanism for CGTs.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Proteínas de Plantas
/
Glicosiltransferasas
/
Fagopyrum
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Plant Cell
Asunto de la revista:
BOTANICA
Año:
2020
Tipo del documento:
Article