1M3W

Crystal Structure of a Molecular Maquette Scaffold


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.80 Å
  • R-Value Free: 0.278 
  • R-Value Work: 0.234 
  • R-Value Observed: 0.234 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

X-ray Structure of a Maquette Scaffold

Huang, S.S.Gibney, B.R.Stayrook, S.E.Dutton, P.L.Lewis, M.

(2003) J Mol Biol 326: 1219-1225

  • DOI: 10.1016/s0022-2836(02)01441-9
  • Primary Citation of Related Structures:  
    1M3W

  • PubMed Abstract: 
  • Maquettes are de novo designed mimicries of nature used to test the construction and engineering criteria of oxidoreductases. One type of scaffold used in maquette construction is a four-alpha-helical bundle. The sequence of the four-alpha-helix bund ...

    Maquettes are de novo designed mimicries of nature used to test the construction and engineering criteria of oxidoreductases. One type of scaffold used in maquette construction is a four-alpha-helical bundle. The sequence of the four-alpha-helix bundle maquettes follows a heptad repeat pattern typical of left-handed coiled-coils. Initial designs were molten globular due partly to the minimalist approach taken by the designers. Subsequent iterative redesign generated several structured scaffolds with similar heme binding properties. Variant [I(6)F(13)](2), a structured scaffold, was partially resolved with NMR spectroscopy and found to have a set of mobile inter-helical packing interfaces. Here, the X-ray structure of a similar peptide ([I(6)F(13)M(31)](2) i.e. ([CGGG EIWKL HEEFLKK FEELLKL HEERLKKM](2))(2) which we call L31M), has been solved using MAD phasing and refined to 2.8A resolution. The structure shows that the maquette scaffold is an anti-parallel four-helix bundle with "up-up-down-down" topology. No pre-formed heme-binding pocket exists in the protein scaffold. We report unexpected inter-helical crossing angles, residue positions and translations between the helices. The crossing angles between the parallel helices are -5 degrees rather than the expected +20 degrees for typical left-handed coiled-coils. Deviation of the scaffold from the design is likely due to the distribution and size of hydrophobic residues. The structure of L31M points out that four identical helices may interact differently in a bundle and heptad repeats with an alternating [HPPHHPP]/[HPPHHPH] (H: hydrophobic, P: polar) pattern are not a sufficient design criterion to generate left-hand coiled-coils.


    Organizational Affiliation

    The Johnson Research Foundation, Department of Biochemistry and Biophysics, School of Medicine, University of Pennsylvania, 37th and Hamilton Walk, Philadelphia, PA 19102-6059, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
H10H24ABCD32N/AMutation(s): 0 
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
HG
Query on HG

Download CCD File 
A, C
MERCURY (II) ION
Hg
BQPIGGFYSBELGY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.80 Å
  • R-Value Free: 0.278 
  • R-Value Work: 0.234 
  • R-Value Observed: 0.234 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 26.9α = 90
b = 48.8β = 104.7
c = 46.7γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
SOLVEphasing
CNSrefinement

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-02-18
    Type: Initial release
  • Version 1.1: 2008-04-28
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance