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Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids
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Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids

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The proline-rich myticalins from Mytilus galloprovincialis display a membrane-permeabilizing antimicrobial mode of

Sabrina Pacor1, Monica Benincasa1, Maria Valentina Musso1

  • 1Department of Life Sciences, Via Licio Giorgieri 5, University of Trieste, 34127 Trieste, Italy.

Peptides
|June 12, 2021
PubMed

Insights

Mussel antimicrobial peptides called myticalins damage bacterial membranes but do not rely on the SbmA transporter. Further research is needed to optimize myticalins for potential antibiotic development due to cytotoxicity concerns.

Area of Science:

  • Marine biology
  • Immunology
  • Biochemistry

Background:

  • Bivalve mollusks face constant exposure to marine pathogens.
  • They possess innate immunity, including antimicrobial peptides, for defense.
  • Myticalins are a novel family of linear cationic peptides found in Mytilus galloprovincialis gills.

Purpose of the Study:

  • Investigate the mechanism of action of myticalins.
  • Compare myticalin function to proline-rich antimicrobial peptides (PrAMPs).
  • Assess myticalin biocompatibility for potential biotechnological applications.

Main Methods:

  • Tested myticalin interaction with the bacterial transporter SbmA.
  • Utilized flow cytometry and atomic force microscopy to assess membrane perturbation and permeabilization in E. coli.
  • Employed circular dichroism spectroscopy to analyze peptide secondary structures in membrane-mimicking environments.
  • Evaluated myticalin cytotoxicity against a human cell line.

Main Results:

  • Myticalins did not utilize the SbmA transporter, unlike some PrAMPs.
  • All tested myticalins effectively perturbed and permeabilized E. coli membranes.
  • Most myticalins showed limited stable secondary structures in amphipathic environments.
  • Myticalins exhibited significant cytotoxic effects on a human cell line.

Conclusions:

  • Myticalins possess a distinct membrane-disrupting antimicrobial mechanism.
  • Their mode of action differs from SbmA-dependent PrAMPs.
  • Cytotoxicity necessitates optimization for future antibiotic development.
Keywords:
Antimicrobial peptideBacteriaMembranolyticMollusksMytilus galloprovincialisProline-rich

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