1NKF

CALCIUM-BINDING PEPTIDE, NMR, 30 STRUCTURES


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 30 
  • Selection Criteria: ENERGY, AGREEMENT WITH EXPERIMENTAL DATA 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Alpha-helix nucleation by a calcium-binding peptide loop.

Siedlecka, M.Goch, G.Ejchart, A.Sticht, H.Bierzyski, A.

(1999) Proc.Natl.Acad.Sci.USA 96: 903-908


  • PubMed Abstract: 
  • A 12-residue peptide AcDKDGDGYISAAENH2 analogous to the third calcium-binding loop of calmodulin strongly coordinates lanthanide ions (K = 10(5) M-1). When metal saturated, the peptide adopts a very rigid structure, the same as in the native protein, ...

    A 12-residue peptide AcDKDGDGYISAAENH2 analogous to the third calcium-binding loop of calmodulin strongly coordinates lanthanide ions (K = 10(5) M-1). When metal saturated, the peptide adopts a very rigid structure, the same as in the native protein, with three last residues AAE fixed in the alpha-helical conformation. Therefore, the peptide provides an ideal helix nucleation site for peptide segments attached to its C terminus. NMR and CD investigations of peptide AcDKDGDGYISAAEAAAQNH2 presented in this paper show that residues A13-Q16 form an alpha-helix of very high stability when the La3+ ion is bound to the D1-E12 loop. In fact, the lowest estimates of the helix content in this segment give values of at least 80% at 1 degreesC and 70% at 25 degreesC. This finding is not compatible with existing helix-coil transition theories and helix propagation parameters, s, reported in the literature. We conclude, therefore, that the initial steps of helix propagation are characterized by much larger s values, whereas helix nucleation is even more unfavorable than is believed. In light of our findings, thermodynamics of the nascent alpha-helices is discussed. The problem of CD spectra of very short alpha-helices is also addressed.


    Organizational Affiliation

    Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warszawa, ul. PawiƄskiego 5A, Poland.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CALCIUM-BINDING HEXADECAPEPTIDE
A
18Homo sapiensMutation(s): 0 
Gene Names: CALM3 (CALML2, CAM3, CAMC, CAMIII)
Find proteins for P0DP25 (Homo sapiens)
Go to Gene View: CALM3
Go to UniProtKB:  P0DP25
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
LA
Query on LA

Download SDF File 
Download CCD File 
A
LANTHANUM (III) ION
La
CZMAIROVPAYCMU-UHFFFAOYSA-N
 Ligand Interaction
Modified Residues  2 Unique
IDChainsTypeFormula2D DiagramParent
NH2
Query on NH2
A
NON-POLYMERH2 N

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ACE
Query on ACE
A
NON-POLYMERC2 H4 O

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Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 30 
  • Selection Criteria: ENERGY, AGREEMENT WITH EXPERIMENTAL DATA 
  • Olderado: 1NKF Olderado
Software Package:
Software NamePurpose
X-PLORmodel building
X-PLORphasing
X-PLORrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-02-16
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance