2K6O

Human LL-37 Structure


Experimental Data Snapshot

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

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structures of human host defense cathelicidin LL-37 and its smallest antimicrobial peptide KR-12 in lipid micelles

Wang, G.

(2008) J.Biol.Chem. 283: 32637-32643

  • DOI: 10.1074/jbc.M805533200

  • PubMed Abstract: 
  • As a key component of the innate immunity system, human cathelicidin LL-37 plays an essential role in protecting humans against infectious diseases. To elucidate the structural basis for its targeting bacterial membrane, we have determined the high q ...

    As a key component of the innate immunity system, human cathelicidin LL-37 plays an essential role in protecting humans against infectious diseases. To elucidate the structural basis for its targeting bacterial membrane, we have determined the high quality structure of (13)C,(15)N-labeled LL-37 by three-dimensional triple-resonance NMR spectroscopy, because two-dimensional (1)H NMR did not provide sufficient spectral resolution. The structure of LL-37 in SDS micelles is composed of a curved amphipathic helix-bend-helix motif spanning residues 2-31 followed by a disordered C-terminal tail. The helical bend is located between residues Gly-14 and Glu-16. Similar chemical shifts and (15)N nuclear Overhauser effect (NOE) patterns of the peptide in complex with dioctanoylphosphatidylglycerol (D8PG) micelles indicate a similar structure. The aromatic rings of Phe-5, Phe-6, Phe-17, and Phe-27 of LL-37, as well as arginines, showed intermolecular NOE cross-peaks with D8PG, providing direct evidence for the association of the entire amphipathic helix with anionic lipid micelles. The structure of LL-37 serves as a model for understanding the structure and function relationship of homologous primate cathelicidins. Using synthetic peptides, we also identified the smallest antibacterial peptide KR-12 corresponding to residues 18-29 of LL-37. Importantly, KR-12 displayed a selective toxic effect on bacteria but not human cells. NMR structural analysis revealed a short three-turn amphipathic helix rich in positively charged side chains, allowing for effective competition for anionic phosphatidylglycerols in bacterial membranes. KR-12 may be a useful peptide template for developing novel antimicrobial agents of therapeutic use.


    Organizational Affiliation

    Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska 68198-6805, USA. gwang@unmc.edu




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Cathelicidin antimicrobial peptide
A
37Homo sapiensGene Names: CAMP (CAP18, FALL39)
Find proteins for P49913 (Homo sapiens)
Go to Gene View: CAMP
Go to UniProtKB:  P49913
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 2K6O Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2008-07-14 
  • Released Date: 2008-09-23 
  • Deposition Author(s): Wang, G.

Revision History 

  • Version 1.0: 2008-09-23
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance