title: Porphyrin-apidaecin conjugate as a new broad spectrum antibacterial agent.
abstract: The conjugation of the cationic antimicrobial peptide, apidaecin Ib, to the anionic photosensitizer, 5(4'-carboxyphenyl)-10,15,20-triphenylporphyrin (cTPP), afforded a new antibacterial agent effective, under light activation, against both Gram-positive and Gram-negative bacteria. At low concentrations (1.5-15 μM) the conjugate was able to reduce the survival of Escherichia coli cells by 3-4 log10, and most notably, it resulted photoactive also against hard-to-treat Pseudomonas aeruginosa, although at higher concentration (60 μM). Under similar conditions, the photosensitizer alone was only photoactive against Staphylococcus aureus while the unconjugated peptide was inactive against all the bacterial strains tested. This study shows the possibility of obtaining new broad-spectrum apidaecin-photosensitizer conjugates with potent antibacterial activity.
authors.affiliation: Department of Biology, University of Padova, via U. Bassi 58/B, 35131 Padova, Italy.
authors.forename: Ryan
authors.initials: R
authors.lastname: Dosselli
authors.affiliation: Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Gobbo
authors.affiliation: Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy.
authors.forename: Erika
authors.initials: E
authors.lastname: Bolognini
authors.affiliation: Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy.
authors.forename: Sandro
authors.initials: S
authors.lastname: Campestrini
authors.affiliation: Department of Biology, University of Padova, via U. Bassi 58/B, 35131 Padova, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Reddi
keywords: Antimicrobial PDT; antimicrobial peptides; apidaecin; photosensitizer−peptide conjugate; porphyrin