2DS2

Crystal structure of mabinlin II


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.221 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structure of Mabinlin II: a novel structural type of sweet proteins and the main structural basis for its sweetness.

Li, D.F.Jiang, P.Zhu, D.Y.Hu, Y.Max, M.Wang, D.C.

(2008) J.Struct.Biol. 162: 50-62

  • DOI: 10.1016/j.jsb.2007.12.007

  • PubMed Abstract: 
  • The crystal structure of a sweet protein Mabinlin II (Mab II) isolated from the mature seeds of Capparis masaikai Levl. grown in Southern China has been determined at 1.7A resolution by the SIRAS method. The Mab II 3D structure features in an "all al ...

    The crystal structure of a sweet protein Mabinlin II (Mab II) isolated from the mature seeds of Capparis masaikai Levl. grown in Southern China has been determined at 1.7A resolution by the SIRAS method. The Mab II 3D structure features in an "all alpha" fold mode consisting of A- and B-chains crosslinked by four disulfide bridges, which is distinct from all known sweet protein structures. The Mabinlin II molecule shows an amphiphilic surface, a cationic face (Face A) and a neutral face (Face B). A unique structural motif consisting of B54-B64 was found in Face B, which adopts a special sequence, NL-P-NI-C-NI-P-NI, featuring four [Asn-Leu/Ile] units connected by three conformational-constrained residues, thus is called the [NL/I] tetralet motif. The experiments for testing the possible interactions of separated A-chain and B-chain and the native Mabinlin II to the sweet-taste receptor were performed through the calcium imaging experiments with the HEK293E cells coexpressed hT1R2/T1R3. The result shows that hT1R2/T1R3 responds to both the integrated Mabinlin II and the individual B-chain in the same scale, but not to A-chain. The sweetness evaluation further identified that the separated B-chain can elicit the sweetness alone, but A-chain does not. All data in combination revealed that the sweet protein Mabinlin II can interact with the sweet-taste receptor hT1R2/T1R3 to elicit its sweet taste, and the B-chain with a unique [NL/I] tetralet motif is the essential structural element for the interaction with sweet-taste receptor to elicit the sweetness, while the A-chain may play a role in gaining a long aftertaste for the integrate Mabinlin II. The findings reported in this paper will be advantage for understanding the diversity of sweet proteins and engineering research for development of a unique sweetener for the food and agriculture based on the Mabinlin II structure as a native model.


    Organizational Affiliation

    National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing 100101, People's Republic of China.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Sweet protein mabinlin-2 chain A
A, C
33Capparis masaikaiMutation(s): 0 
Find proteins for P30233 (Capparis masaikai)
Go to UniProtKB:  P30233
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Sweet protein mabinlin-2 chain B
B, D
72Capparis masaikaiMutation(s): 0 
Find proteins for P30233 (Capparis masaikai)
Go to UniProtKB:  P30233
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ACY
Query on ACY

Download SDF File 
Download CCD File 
D
ACETIC ACID
C2 H4 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.221 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 80.110α = 90.00
b = 51.080β = 122.77
c = 47.340γ = 90.00
Software Package:
Software NamePurpose
SHARPphasing
CrystalCleardata reduction
CRYSTALdata collection
CNSrefinement
SCALAdata scaling

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-06-12
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance