1GO9

Monitoring the structural Consequences of Phe12-->D-Phe12 and Leu15-->Aib15 substitution in h/r Corticotropin Releasing Hormone: Implications for Design of CRH antagonists.


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 40 
  • Conformers Submitted: 
  • Selection Criteria: LEAST RESTRAINT VIOLATION 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Monitoring the Structural Consequences of Phe12-->D-Phe and Leu15-->Aib Substitution in Human/Rat Corticotropin Releasing Hormone. Implications for Design of Crh Antagonists.

Spyroulias, G.A.Papazacharias, S.Pairas, G.Cordopatis, P.

(2002) Eur.J.Biochem. 269: 6009

  • Primary Citation of Related Structures:  1GOE

  • PubMed Abstract: 
  • A new human/rat CRH analogue has been synthesized using the Fmoc/tBu solid-phase synthetic protocol. The sequence of the new peptide differs from the original in two positions, 12 and 15, at which the native amino acids l-phenylalanine 12 and l-leuci ...

    A new human/rat CRH analogue has been synthesized using the Fmoc/tBu solid-phase synthetic protocol. The sequence of the new peptide differs from the original in two positions, 12 and 15, at which the native amino acids l-phenylalanine 12 and l-leucine 15 have been replaced by the nonprotein amino acids d-phenylalanine and alpha-aminoisobutyric acid (Aib), respectively. The high resolution three-dimensional solution structure of [d-Phe12, Aib15]CRH has been determined by 688 distance constraints (656 meaningful NOE and 32 H-bonds distance limits) and 21 angle constraints. A family of 40 energy-minimized conformers was obtained with average rmsd of 0.39 +/- 0.16 A and 0.99 +/- 0.13 A for backbone and heavy atoms, respectively, and distance penalty functions of 0.42 +/- 0.03 A2. The NMR data acquired in a solvent system of water/trifluoroethanol (34%/66%, v/v) revealed that this 41-polypeptide adopts an almost linear helical structure in solution with helical content which reaches an 84% of the residues. Structural analysis confirmed the existence of two helical peptide fragments. The first was comprised of residues Ile6-Arg16 and the second of residues Glu20-Ile40, forming an angle of 34.2 degrees. The structural differences with respect to the native peptide have been identified in the region d-Phe12-Glu20 where double substitution at positions 12 and 15 seems to perturb the elements of the native 35-residue helix. These structural rearrangements promote non-native intramolecular interactions in the region of the molecule between either the hydrophobic side-chains of d-Phe12, Aib15 and Leu18, or the charged groups of the residue pairs Arg16-Glu20 and His13-Glu17 being responsible for changes in hormonal functionality. This CRH analogue currently exhibits lack of any activity.


    Related Citations: 
    • Solution Structure of Human Corticotropin Releasing Factor by 1H NMR and Distance Geometry with Restrained Molecular Dynamics.
      Romier, C.,Bernassau, J.M.,Cambillau, C.,Darbon, H.
      (1993) Protein Eng. 6: 149


    Organizational Affiliation

    Department of Pharmacy, University of Patras, Greece.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CORTICOTROPIN RELEASING HORMONE
A
42Homo sapiensGene Names: CRH
Find proteins for P06850 (Homo sapiens)
Go to Gene View: CRH
Go to UniProtKB:  P06850
Small Molecules
Modified Residues  3 Unique
IDChainsTypeFormula2D DiagramParent
NH2
Query on NH2
A
NON-POLYMERH2 N

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AIB
Query on AIB
A
L-PEPTIDE LINKINGC4 H9 N O2ALA
DPN
Query on DPN
A
D-PEPTIDE LINKINGC9 H11 N O2

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Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 40 
  • Conformers Submitted: 
  • Selection Criteria: LEAST RESTRAINT VIOLATION 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-10-31
    Type: Initial release
  • Version 1.1: 2016-12-21
    Type: Database references, Derived calculations, Other, Source and taxonomy, Structure summary, Version format compliance