Enhanced stability and activity of an antimicrobial peptide in conjugation with silver nanoparticle

J Colloid Interface Sci. 2016 Dec 1:483:385-393. doi: 10.1016/j.jcis.2016.08.043. Epub 2016 Aug 20.

Abstract

The conjugation of nanoparticles with antimicrobial peptides (AMP) is emerging as a promising route to achieve superior antimicrobial activity. However, the nature of peptide-nanoparticle interactions in these systems remains unclear. This study describes a system consisting of a cysteine containing antimicrobial peptide conjugated with silver nanoparticles, in which the two components exhibit a dynamic interaction resulting in a significantly enhanced stability and biological activity compared to that of the individual components. This was investigated using NMR spectroscopy in conjunction with other biophysical techniques. Using fluorescence assisted cell sorting and membrane mimics we carried out a quantitative comparison of the activity of the AMP-nanoparticle system and the free peptide. Taken together, the study provides new insights into nanoparticle-AMP interactions at a molecular level and brings out the factors that will be useful for consideration while designing new conjugates with enhanced functionality.

Keywords: Antimicrobial peptide; Fast chemical exchange; Membrane interaction; NMR spectroscopy; Peptide nanoparticle conjugate; Silver nanoparticle.

MeSH terms

  • Amino Acid Sequence
  • Anti-Bacterial Agents / chemistry*
  • Anti-Bacterial Agents / pharmacology
  • Antimicrobial Cationic Peptides / chemistry*
  • Antimicrobial Cationic Peptides / pharmacology
  • Biomimetic Materials / chemistry
  • Cell Line
  • Cell Membrane / chemistry
  • Cell Membrane / drug effects
  • Cell Survival / drug effects
  • Cysteine / chemistry
  • Cysteine / metabolism
  • Drug Stability
  • Escherichia coli / drug effects
  • Escherichia coli / growth & development
  • Humans
  • Keratinocytes / cytology
  • Keratinocytes / drug effects
  • Magnetic Resonance Spectroscopy
  • Metal Nanoparticles / chemistry*
  • Metal Nanoparticles / ultrastructure
  • Microbial Viability / drug effects
  • Phosphatidylethanolamines / chemistry
  • Phosphatidylglycerols / chemistry
  • Silver / chemistry*
  • Unilamellar Liposomes / chemistry

Substances

  • Anti-Bacterial Agents
  • Antimicrobial Cationic Peptides
  • Phosphatidylethanolamines
  • Phosphatidylglycerols
  • Unilamellar Liposomes
  • 1-palmitoyl-2-oleoylphosphatidylethanolamine
  • Silver
  • 1-palmitoyl-2-oleoylglycero-3-phosphoglycerol
  • Cysteine