1DFY

NMR STRUCTURE OF CONTRYPHAN-SM CYCLIC PEPTIDE (MAJOR FORM-CIS)


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structures of the contryphan family of cyclic peptides. Role of electrostatic interactions in cis-trans isomerism.

Pallaghy, P.K.He, W.Jimenez, E.C.Olivera, B.M.Norton, R.S.

(2000) Biochemistry 39: 12845-12852

  • Primary Citation of Related Structures:  1DFZ, 1DG0

  • PubMed Abstract: 
  • The contryphan family of cyclic peptides, isolated recently from various species of cone shell, has the conserved sequence motif NH(3)(+)-X(1)COD-WX(5)PWC-NH(2), where X(1) is either Gly or absent, O is 4-trans-hydroxyproline, and X(5) is Glu, Asp, o ...

    The contryphan family of cyclic peptides, isolated recently from various species of cone shell, has the conserved sequence motif NH(3)(+)-X(1)COD-WX(5)PWC-NH(2), where X(1) is either Gly or absent, O is 4-trans-hydroxyproline, and X(5) is Glu, Asp, or Gln. The solution structures described herein of two new naturally occurring contryphan sequences, contryphan-Sm and des[Gly1]-contryphan-R, are similar to those of contryphan-R, the structure of which has been determined recently [Pallaghy et al. (1999) Biochemistry 38, 11553-11559]. The (1)H NMR chemical shifts of another naturally occurring peptide, contryphan-P, indicate that it also adopts a similar structure. All of these contryphans exist in solution as a mixture of two conformers due to cis-trans isomerization about the Cys2-Hyp3 peptide bond. The lower cis-trans ratio for contryphan-Sm enabled elucidation of the 3D structure of both its major and its minor forms, for which the patterns of (3)J(H)(alpha)(HN) coupling constants are very different. As with contryphan-R, the structure of the major form of contryphan-Sm (cis Cys2-Hyp3 peptide bond) contains an N-terminal chain reversal and a C-terminal type I beta-turn. The minor conformer (trans peptide bond) forms a hairpin structure with sheetlike hydrogen bonds and a type II beta-turn, with the D-Trp4 at the 'Gly position' of the turn. The ratio of conformers arising from cis-trans isomerism around the peptide bond preceding Hyp3 is sensitive to both the amino acid sequence and the solution conditions, varying from 2.7:1 to 17:1 across the five sequences. The sequence and structural determinants of the cis-trans isomerism have been elucidated by comparison of the cis-trans ratios for these peptides with those for contryphan-R and an N-acetylated derivative thereof. The cis-trans ratio is reduced for peptides in which either the charged N-terminal ammonium or the X(5) side-chain carboxylate is neutralized, implying that an electrostatic interaction between these groups stabilizes the cis conformer relative to the trans. These results on the structures and cis-trans equilibrium of different conformers suggest a paradigm of 'locally determined but globally selected' folding for cyclic peptides and constrained protein loops, where the series of stereochemical centers in the loop dictates the favorable conformations and the equilibrium is determined by a small number of side-chain interactions.


    Organizational Affiliation

    Biomolecular Research Institute, 343 Royal Parade, Parkville 3052, Australia.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CONTRYPHAN-SM
A
8Conus stercusmuscarumN/A
Find proteins for P58787 (Conus stercusmuscarum)
Go to UniProtKB:  P58787
Small Molecules
Modified Residues  3 Unique
IDChainsTypeFormula2D DiagramParent
CY3
Query on CY3
A
L-PEPTIDE LINKINGC3 H8 N2 O SCYS
HYP
Query on HYP
A
L-PEPTIDE LINKINGC5 H9 N O3PRO
DTR
Query on DTR
A
D-PEPTIDE LINKINGC11 H12 N2 O2

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Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 1DFY Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-05-01
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance