Peptide conjugates of lactoferricin analogues and antimicrobials—Design, chemical synthesis, and evaluation of antimicrobial activity and mammalian cytotoxicity

Publication date: July 2019Source: Peptides, Volume 117Author(s): Natalia Ptaszyńska, Katarzyna Olkiewicz, Joanna Okońska, Katarzyna Gucwa, Anna Łęgowska, Agata Gitlin-Domagalska, Dawid Dębowski, Jan Lica, Mateusz Heldt, Sławomir Milewski, Tzi Bun Ng, Krzysztof RolkaAbstractEight new peptide conjugates composed of modified bovine lactoferricin truncated analogues (LFcinB) and one of the three antimicrobials — ciprofloxacin (CIP), levofloxacin (LVX), and fluconazole (FLC) — were synthesized. Four different linkers were applied to connect a peptide and an antimicrobial agent. The FLC-containing peptidic conjugates were synthesized using the “click chemistry” method. This novel approach is reported here for the first time. Unlike their components, CIP- and LVX-based conjugates exerted activity against Candida yeast. Similarly to the constituent peptides, synthesized conjugates showed activity against Gram-positive bacteria, especially S. epidermidis. The most active were the conjugates containing CIP linked to the peptide by the redox-sensitive disulfide bridge. Our results show a significant role of a linker between antimicrobial agent and a peptide. This was also confirmed by the lack of synergistic effects on the antimicrobial activity of the constituent compounds. Moreover, cytotoxicity assays revealed that the proposed conjugates cause a comparatively low cytotoxic effect in reference to antibiotics widely used in therapies. Therefore, they can be deliberated ...
Source: Peptides - Category: Biochemistry Source Type: research