Synthesis, spectroscopic, and photophysical characterization and photosensitizing activity toward prokaryotic and eukaryotic cells of porphyrin-magainin and -buforin conjugates

J Med Chem. 2014 Feb 27;57(4):1403-15. doi: 10.1021/jm401653r. Epub 2014 Feb 5.

Abstract

Cationic antimicrobial peptides (CAMPs) and photodynamic therapy (PDT) are attractive tools to combat infectious diseases and to stem further development of antibiotic resistance. In an attempt to increase the efficiency of bacteria inactivation, we conjugated a PDT photosensitizer, cationic or neutral porphyrin, to a CAMP, buforin or magainin. The neutral and hydrophobic porphyrin, which is not photoactive per se against Gram-negative bacteria, efficiently photoinactivated Escherichia coli after conjugation to either buforin or magainin. Conjugation to magainin resulted in the considerable strengthening of the cationic and hydrophilic porphyrin's interaction with the bacterial cells, as shown by the higher bacteria photoinactivation activity retained after washing the bacterial suspension. The porphyrin-peptide conjugates also exhibited strong interaction capability as well as photoactivity toward eukaryotic cells, namely, human fibroblasts. These findings suggest that these CAMPs have the potential to carry drugs and other types of cargo inside mammalian cells similar to cell-penetrating peptides.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Circular Dichroism
  • Eukaryotic Cells / drug effects
  • Gram-Negative Bacteria / drug effects
  • Magainins / chemistry*
  • Molecular Sequence Data
  • Photochemotherapy
  • Photosensitizing Agents / chemical synthesis*
  • Photosensitizing Agents / chemistry
  • Photosensitizing Agents / pharmacology*
  • Porphyrins / chemistry*
  • Spectrophotometry, Ultraviolet

Substances

  • Magainins
  • Photosensitizing Agents
  • Porphyrins