5XNG

EFK17A structure in Microgel MAA60


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.0 of the entry. See complete history

Literature

Conformational Aspects of High Content Packing of Antimicrobial Peptides in Polymer Microgels

Singh, S.Datta, A.Borro, B.C.Davoudi, M.Schmidtchen, A.Bhunia, A.Malmsten, M.

(2017) ACS Appl Mater Interfaces 9: 40094-40106

  • DOI: 10.1021/acsami.7b13714
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Successful use of microgels as delivery systems of antimicrobial peptides (AMPs) requires control of factors determining peptide loading and release to/from the microgels as well as of membrane interactions of both microgel particles and released pep ...

    Successful use of microgels as delivery systems of antimicrobial peptides (AMPs) requires control of factors determining peptide loading and release to/from the microgels as well as of membrane interactions of both microgel particles and released peptides. Addressing these, we here investigate effects of microgel charge density and conformationally induced peptide amphiphilicity on AMP loading and release using detailed nuclear magnetic resonance (NMR) structural studies combined with ellipsometry, isothermal titration calorimetry, circular dichroism, and light scattering. In parallel, consequences of peptide loading and release for membrane interactions and antimicrobial effects were investigated. In doing so, poly(ethyl acrylate-co-methacrylic acid) microgels were found to incorporate the cationic AMPs EFK17a (EFKRIVQRIKDFLRNLV) and its partially d-amino acid-substituted variant EFK17da (E(dF)KR(dI)VQR(dI)KD(dF)LRNLV). Peptide incorporation was found to increase with increasing with microgel charge density and peptide amphiphilicity. After microgel incorporation, which appeared to occur preferentially in the microgel core, NMR showed EFK17a to form a helix with pronounced amphiphilicity, while EFK17da displayed a folded conformation, stabilized by a hydrophobic hub consisting of aromatic/aromatic and aliphatic/aromatic interactions, resulting in much lower amphiphilicity. Under wide ranges of peptide loading, the microgels displayed net negative z-potential. Such negatively charged microgels do not bind to, nor lyse, bacteria-mimicking membranes. Instead, membrane disruption in these systems is mediated largely by peptide release, which in turn is promoted at higher ionic strength and lower peptide amphiphilicity. Analogously, antimicrobial effects against Escherichia coli were found to be dictated by peptide release. Taken together, the findings show that peptide loading, packing, and release strongly affect the performance of microgels as AMP delivery systems, effects that can be tuned by (conformationally induced) peptide amphiphilicity and by microgel charge density.


    Organizational Affiliation

    Department of Pharmacy, University of Copenhagen , DK-2100 Copenhagen, Denmark.,Wound Healing Centre, Bispebjerg University Hospital , DK-2100 Copenhagen, Denmark.,Department of Biophysics, Bose Institute , P-1/12 CIT Scheme VII (M), Kolkata 700054, India.,Division of Dermatology and Venereology, Department of Clinical Sciences, Lund University , SE-221 84 Lund, Sweden.,Lee Kong Chian School of Medicine, Nanyang Technological University , 11 Mandalay Road, Singapore 308232, Singapore.,Department of Pharmacy, Uppsala University , SE-75232 Uppsala, Sweden.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Cathelicidin antimicrobial peptide
A
17Homo sapiensMutation(s): 0 
Gene 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: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2017-05-22 
  • Released Date: 2018-04-18 
  • Deposition Author(s): Datta, A., Bhunia, A.

Revision History 

  • Version 1.0: 2018-04-18
    Type: Initial release