3Q6E

Human insulin in complex with cucurbit[7]uril


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.253 
  • R-Value Work: 0.206 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Molecular recognition of insulin by a synthetic receptor.

Chinai, J.M.Taylor, A.B.Ryno, L.M.Hargreaves, N.D.Morris, C.A.Hart, P.J.Urbach, A.R.

(2011) J.Am.Chem.Soc. 133: 8810-8813

  • DOI: 10.1021/ja201581x

  • PubMed Abstract: 
  • The discovery of molecules that bind tightly and selectively to desired proteins continues to drive innovation at the interface of chemistry and biology. This paper describes the binding of human insulin by the synthetic receptor cucurbit[7]uril (Q7) ...

    The discovery of molecules that bind tightly and selectively to desired proteins continues to drive innovation at the interface of chemistry and biology. This paper describes the binding of human insulin by the synthetic receptor cucurbit[7]uril (Q7) in vitro. Isothermal titration calorimetry and fluorescence spectroscopy experiments show that Q7 binds to insulin with an equilibrium association constant of 1.5 × 10(6) M(-1) and with 50-100-fold selectivity versus proteins that are much larger but lack an N-terminal aromatic residue, and with >1000-fold selectivity versus an insulin variant lacking the N-terminal phenylalanine (Phe) residue. The crystal structure of the Q7·insulin complex shows that binding occurs at the N-terminal Phe residue and that the N-terminus unfolds to enable binding. These findings suggest that site-selective recognition is based on the properties inherent to a protein terminus, including the unique chemical epitope presented by the terminal residue and the greater freedom of the terminus to unfold, like the end of a ball of string, to accommodate binding. Insulin recognition was predicted accurately from studies on short peptides and exemplifies an approach to protein recognition by targeting the terminus.


    Organizational Affiliation

    Department of Chemistry, Trinity University, One Trinity Place, San Antonio, Texas 78212, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Insulin A chain
A, C
21Homo sapiensMutation(s): 0 
Gene Names: INS
Find proteins for P01308 (Homo sapiens)
Go to Gene View: INS
Go to UniProtKB:  P01308
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Insulin B chain
B, D
30Homo sapiensMutation(s): 0 
Gene Names: INS
Find proteins for P01308 (Homo sapiens)
Go to Gene View: INS
Go to UniProtKB:  P01308
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
QQ7
Query on QQ7

Download SDF File 
Download CCD File 
D
cucurbit[7]uril
C42 H42 N28 O14
ZDOBFUIMGBWEAB-XGFHMVPTSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.253 
  • R-Value Work: 0.206 
  • Space Group: I 41 3 2
Unit Cell:
Length (Å)Angle (°)
a = 116.534α = 90.00
b = 116.534β = 90.00
c = 116.534γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
PHENIXrefinement
HKL-2000data scaling
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-04-20
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2011-11-02
    Type: Database references
  • Version 1.3: 2014-02-19
    Type: Other