1 research outputs found
Synthesis, Characterization, and Photoinduced Antibacterial Activity of Porphyrin-Type Photosensitizers Conjugated to the Antimicrobial Peptide Apidaecin 1b
Antimicrobial photodynamic therapy (aPDT) is an emerging
treatment
for bacterial infections that is becoming increasingly more attractive
because of its effectiveness against multi-antibiotic-resistant strains
and unlikelihood of inducing bacterial resistance. Among the strategies
to enhance the efficacy of PDT against Gram-negative bacteria, the
binding to a cationic antimicrobial peptide offers the attractive
prospect for improving both the water solubilty and the localization
of the photoactive drug in bacteria. In this work we have compared
a number of free and apidaecin-conjugated photosensitizers (PSs) differing
in structure and charge. Our results indicate that the conjugation
of per se ineffective highly hydrophobic PSs to a cationic peptide
produces a photosensitizing agent effective against Gram-negative
bacteria. Apidaecin cannot improve the phototoxic activity of cationic
PSs, which mainly depends on a very high yield of singlet oxygen production
in the surroundings of the bacterial outer membrane. Apidaecin–PS
conjugates appear most promising for treatment protocols requiring
repeated washing after sensitizer delivery