6O87

Crystal Structure of UDP-dependent glucosyltransferases (UGT) from Stevia rebaudiana in complex with UDP


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.194 
  • R-Value Work: 0.173 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Molecular basis for branched steviol glucoside biosynthesis.

Lee, S.G.Salomon, E.Yu, O.Jez, J.M.

(2019) Proc.Natl.Acad.Sci.USA 116: 13131-13136

  • DOI: 10.1073/pnas.1902104116
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Steviol glucosides, such as stevioside and rebaudioside A, are natural products roughly 200-fold sweeter than sugar and are used as natural, noncaloric sweeteners. Biosynthesis of rebaudioside A, and other related stevia glucosides, involves formatio ...

    Steviol glucosides, such as stevioside and rebaudioside A, are natural products roughly 200-fold sweeter than sugar and are used as natural, noncaloric sweeteners. Biosynthesis of rebaudioside A, and other related stevia glucosides, involves formation of the steviol diterpenoid followed by a series of glycosylations catalyzed by uridine diphosphate (UDP)-dependent glucosyltransferases. UGT76G1 from Stevia rebaudiana catalyzes the formation of the branched-chain glucoside that defines the stevia molecule and is critical for its high-intensity sweetness. Here, we report the 3D structure of the UDP-glucosyltransferase UGT76G1, including a complex of the protein with UDP and rebaudioside A bound in the active site. The X-ray crystal structure and biochemical analysis of site-directed mutants identifies a catalytic histidine and how the acceptor site of UGT76G1 achieves regioselectivity for branched-glucoside synthesis. The active site accommodates a two-glucosyl side chain and provides a site for addition of a third sugar molecule to the C3' position of the first C13 sugar group of stevioside. This structure provides insight on the glycosylation of other naturally occurring sweeteners, such as the mogrosides from monk fruit, and a possible template for engineering of steviol biosynthesis.


    Organizational Affiliation

    National Center for Mariculture, Israel Oceanographic and Limnological Research, Eilat, 8811201, Israel.,Department of Biology, Washington University in St. Louis, St. Louis, MO 63130.,Department of Chemistry & Biochemistry, University of North Carolina Wilmington, Wilmington, NC 28403.,Conagen, Inc., Bedford, MA 01730.,Department of Biology, Washington University in St. Louis, St. Louis, MO 63130; jjez@wustl.edu.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
UDP-glycosyltransferase 76G1
A
458Stevia rebaudianaMutation(s): 0 
Gene Names: UGT76G1
EC: 2.4.1.-
Find proteins for Q6VAB4 (Stevia rebaudiana)
Go to UniProtKB:  Q6VAB4
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
UDP
Query on UDP

Download SDF File 
Download CCD File 
A
URIDINE-5'-DIPHOSPHATE
C9 H14 N2 O12 P2
XCCTYIAWTASOJW-XVFCMESISA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.75 Å
  • R-Value Free: 0.194 
  • R-Value Work: 0.173 
  • Space Group: P 31 2 1
Unit Cell:
Length (Å)Angle (°)
a = 98.454α = 90.00
b = 98.454β = 90.00
c = 90.667γ = 120.00
Software Package:
Software NamePurpose
PHASERphasing
Cootmodel building
PHENIXrefinement
HKL-3000data collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2019-03-09 
  • Released Date: 2019-06-12 
  • Deposition Author(s): Lee, S.G., Jez, J.M.

Revision History 

  • Version 1.0: 2019-06-12
    Type: Initial release
  • Version 1.1: 2019-06-26
    Type: Data collection, Database references
  • Version 1.2: 2019-07-10
    Type: Data collection, Database references