5X9M

Structure of hyper-sweet thaumatin (D21N)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 0.93 Å
  • R-Value Free: 0.147 
  • R-Value Work: 0.137 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Subatomic structure of hyper-sweet thaumatin D21N mutant reveals the importance of flexible conformations for enhanced sweetness.

Masuda, T.Okubo, K.Murata, K.Mikami, B.Sugahara, M.Suzuki, M.Temussi, P.A.Tani, F.

(2019) Biochimie 157: 57-63

  • DOI: 10.1016/j.biochi.2018.10.020
  • Primary Citation of Related Structures:  
    5X9L, 5X9M

  • PubMed Abstract: 
  • One of the sweetest proteins found in tropical fruits (with a threshold of 50 nM), thaumatin, is also used commercially as a sweetener. Our previous study successfully produced the sweetest thaumatin mutant (D21N), designated hyper-sweet thaumatin, which decreases the sweetness threshold to 31 nM ...

    One of the sweetest proteins found in tropical fruits (with a threshold of 50 nM), thaumatin, is also used commercially as a sweetener. Our previous study successfully produced the sweetest thaumatin mutant (D21N), designated hyper-sweet thaumatin, which decreases the sweetness threshold to 31 nM. To investigate why the D21N mutant is sweeter than wild-type thaumatin, we compared the structure of the D21N mutant solved at a subatomic resolution of 0.93 Å with that of wild-type thaumatin determined at 0.90 Å. Although the overall structure of the D21N mutant resembles that of wild-type thaumatin, our subatomic resolution analysis successfully assigned and discriminated the detailed atomic positions of side-chains at position 21. The relative B-factor value of the side-chain at position 21 in the D21N mutant was higher than that of wild-type thaumatin, hinting at a greater flexibility of side-chain at 21 in the hyper-sweet D21N mutant. Furthermore, alternative conformations of Lys19, which is hydrogen-bonded to Asp21 in wild-type, were found only in the D21N mutant. Subatomic resolution analysis revealed that flexible conformations at the sites adjacent to positions 19 and 21 play a crucial role in enhancing sweet potency and may serve to enhance the complementarity of electrostatic potentials for interaction with the sweet taste receptor.


    Organizational Affiliation

    Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Thaumatin IA207Thaumatococcus danielliiMutation(s): 1 
UniProt
Find proteins for P02883 (Thaumatococcus daniellii)
Explore P02883 
Go to UniProtKB:  P02883
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
TLA
Query on TLA

Download Ideal Coordinates CCD File 
B [auth A], C [auth A]L(+)-TARTARIC ACID
C4 H6 O6
FEWJPZIEWOKRBE-JCYAYHJZSA-N
 Ligand Interaction
GOL
Query on GOL

Download Ideal Coordinates CCD File 
D [auth A], E [auth A], F [auth A]GLYCEROL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 0.93 Å
  • R-Value Free: 0.147 
  • R-Value Work: 0.137 
  • Space Group: P 41 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 57.964α = 90
b = 57.964β = 90
c = 150.222γ = 90
Software Package:
Software NamePurpose
SHELXphasing
HKL-2000data collection
HKL-2000data scaling
SHELXL-97refinement

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2018-03-14
    Type: Initial release
  • Version 1.1: 2019-03-27
    Changes: Data collection, Database references