5WLK

De Novo Design of Polynuclear Transition Metal Clusters in Helix Bundles-4EH2


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.178 
  • R-Value Work: 0.168 
  • R-Value Observed: 0.169 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

De Novo Design of Tetranuclear Transition Metal Clusters Stabilized by Hydrogen-Bonded Networks in Helical Bundles.

Zhang, S.Q.Chino, M.Liu, L.Tang, Y.Hu, X.DeGrado, W.F.Lombardi, A.

(2018) J Am Chem Soc 140: 1294-1304

  • DOI: 10.1021/jacs.7b08261
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • De novo design provides an attractive approach to test the mechanism by which metalloproteins define the geometry and reactivity of their metal ion cofactors. While there has been considerable progress in designing proteins that bind transition metal ...

    De novo design provides an attractive approach to test the mechanism by which metalloproteins define the geometry and reactivity of their metal ion cofactors. While there has been considerable progress in designing proteins that bind transition metal ions including iron-sulfur clusters, the design of tetranuclear clusters with oxygen-rich environments has not been accomplished. Here, we describe the design of tetranuclear clusters, consisting of four Zn 2+ and four carboxylate oxygens situated at the vertices of a distorted cube-like structure. The tetra-Zn 2+ clusters are bound at a buried site within a four-helix bundle, with each helix donating a single carboxylate (Glu or Asp) and imidazole (His) ligand, as well as second- and third-shell ligands. Overall, the designed site consists of four Zn 2+ and 16 polar side chains in a fully connected hydrogen-bonded network. The designed proteins have apolar cores at the top and bottom of the bundle, which drive the assembly of the liganding residues near the center of the bundle. The steric bulk of the apolar residues surrounding the binding site was varied to determine how subtle changes in helix-helix packing affect the binding site. The crystal structures of two of four proteins synthesized were in good agreement with the overall design; both formed a distorted cuboidal site stabilized by flanking second- and third-shell interactions that stabilize the primary ligands. A third structure bound a single Zn 2+ in an unanticipated geometry, and the fourth bound multiple Zn 2+ at multiple sites at partial occupancy. The metal-binding and conformational properties of the helical bundles in solution, probed by circular dichroism spectroscopy, analytical ultracentrifugation, and NMR, were consistent with the crystal structures.


    Organizational Affiliation

    Department of Chemical Sciences, University of Napoli "Federico II" , Via Cintia, 46, 80126 Napoli, Italy.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Helical Bundle 4EH2
A, B, C, D
28synthetic constructMutation(s): 0 
Protein Feature View
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download CCD File 
A, C
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.178 
  • R-Value Work: 0.168 
  • R-Value Observed: 0.169 
  • Space Group: P 31 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 80.995α = 90
b = 80.995β = 90
c = 65.308γ = 120
Software Package:
Software NamePurpose
REFMACrefinement
HKL-2000data reduction
SCALEPACKdata scaling
PHASERphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesGM54616

Revision History 

  • Version 1.0: 2018-01-03
    Type: Initial release
  • Version 1.1: 2018-01-31
    Changes: Database references
  • Version 1.2: 2018-02-07
    Changes: Database references
  • Version 1.3: 2020-01-01
    Changes: Author supporting evidence