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 1IN3 | pdb_00001in3

Peptide Antagonist of IGFBP1, (i,i+8) Covalently Restrained Analog


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 80 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the least restraint violations 

wwPDB Validation 3D Report Full Report

Validation slider image for 1IN3

This is version 1.3 of the entry. See complete history. 

Literature

Structure-function analysis of a phage display-derived peptide that binds to insulin-like growth factor binding protein 1.

Skelton, N.J., Chen, Y.M., Dubree, N., Quan, C., Jackson, D.Y., Cochran, A., Zobel, K., Deshayes, K., Baca, M., Pisabarro, M.T., Lowman, H.B.

(2001) Biochemistry 40: 8487-8498

  • DOI: https://doi.org/10.1021/bi0103866
  • Primary Citation Related Structures: 
    1GJE, 1GJF, 1GJG, 1IMW, 1IN2, 1IN3

  • PubMed Abstract: 

    Highly structured, peptide antagonists of the interaction between insulin-like growth factor 1 (IGF-I) and IGF binding protein 1 (IGFBP-1) have recently been discovered by phage display of naïve peptide libraries [Lowman, H. B., et al. (1998) Biochemistry 37, 8870--8878]. We now report a detailed analysis of the features of this turn-helix peptide motif that are necessary for IGFBP-1 binding and structural integrity. Further rounds of phage randomization indicate the importance of residues contributing to a hydrophobic patch on one face of the helix. Alanine-scanning substitutions confirm that the hydrophobic residues are necessary for binding. However, structural analysis by NMR spectroscopy indicates that some of these analogues are less well folded. Structured, high-affinity analogues that lack the disulfide bond were prepared by introducing a covalent constraint between side chains at positions i and i + 7 or i + 8 within the helix. Analogues based on this scaffold demonstrate that a helical conformation is present in the bound state, and that hydrophobic side chains in this helix, and residues immediately preceding it, interact with IGFBP-1. By comparison of alanine scanning data for IGF-I and the turn-helix peptide, we propose a model for common surface features of these molecules that recognize IGFBP-1.


  • Organizational Affiliation: 
    • Department of Protein Engineering, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, USA. skelly@gene.com

Macromolecule Content 

  • Total Structure Weight: 1.68 kDa 
  • Atom Count: 121 
  • Modeled Residue Count: 14 
  • Deposited Residue Count: 14 
  • Unique protein chains: 1

Macromolecules

Find similar proteins by:  Sequence   |   3D Structure  
Entity ID: 1
MoleculeChains  Sequence LengthOrganismDetailsImage
IGFBP-1 antagonist14N/AMutation(s): 0 
Entity Groups
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
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Reference Sequence

Small Molecules

Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
LNK

Query on LNK



Download:Ideal Coordinates CCD File
B [auth A]PENTANE
C5 H12
OFBQJSOFQDEBGM-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 80 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the least restraint violations 

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2001-05-30
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Atomic model, Database references, Derived calculations, Non-polymer description, Structure summary, Version format compliance
  • Version 1.3: 2024-11-06
    Changes: Data collection, Database references, Derived calculations, Structure summary