2KB8

The dynamic alpha-helix structure of micelle-bound human amylin.


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 30 
  • Selection Criteria: structures with the least restraint violations 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Dynamic alpha-helix structure of micelle-bound human amylin.

Patil, S.M.Xu, S.Sheftic, S.R.Alexandrescu, A.T.

(2009) J.Biol.Chem. 284: 11982-11991

  • DOI: 10.1074/jbc.M809085200

  • PubMed Abstract: 
  • Amylin is an endocrine hormone that regulates metabolism. In patients afflicted with type 2 diabetes, amylin is found in fibrillar deposits in the pancreas. Membranes are thought to facilitate the aggregation of amylin, and membrane-bound oligomers m ...

    Amylin is an endocrine hormone that regulates metabolism. In patients afflicted with type 2 diabetes, amylin is found in fibrillar deposits in the pancreas. Membranes are thought to facilitate the aggregation of amylin, and membrane-bound oligomers may be responsible for the islet beta-cell toxicity that develops during type 2 diabetes. To better understand the structural basis for the interactions between amylin and membranes, we determined the NMR structure of human amylin bound to SDS micelles. The first four residues in the structure are constrained to form a hairpin loop by the single disulfide bond in amylin. The last nine residues near the C terminus are unfolded. The core of the structure is an alpha-helix that runs from about residues 5-28. A distortion or kink near residues 18-22 introduces pliancy in the angle between the N- and C-terminal segments of the alpha-helix. Mobility, as determined by (15)N relaxation experiments, increases from the N to the C terminus and is strongly correlated with the accessibility of the polypeptide to spin probes in the solution phase. The spin probe data suggest that the segment between residues 5 and 17 is positioned within the hydrophobic lipid environment, whereas the amyloidogenic segment between residues 20 and 29 is at the interface between the lipid and solvent. This orientation may direct the aggregation of amylin on membranes, whereas coupling between the two segments may mediate the transition to a toxic structure.


    Organizational Affiliation

    Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut 06269-3125, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Islet amyloid polypeptide
A
37Homo sapiensMutation(s): 0 
Gene Names: IAPP
Find proteins for P10997 (Homo sapiens)
Go to Gene View: IAPP
Go to UniProtKB:  P10997
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 30 
  • Selection Criteria: structures with the least restraint violations 
  • Olderado: 2KB8 Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-02-24
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance