Frog Skin-Derived Peptides Against Corynebacterium jeikeium: Correlation between Antibacterial and Cytotoxic Activities

Abstract

Corynebacterium jeikeium is a commensal bacterium that colonizes human skin, and it is part of the normal bacterial flora. In non-risk subjects, it can be the cause of bad body smell due to the generation of volatile odorous metabolites, especially in the wet parts of the body that this bacterium often colonizes (i.e., groin and axillary regions). Importantly, in the last few decades, there have been increasing cases of serious infections provoked by this bacterium, especially in immunocompromised or hospitalized patients who have undergone installation of prostheses or catheters. The ease in developing resistance to commonly-used antibiotics (i.e., glycopeptides) has made the search for new antimicrobial compounds of clinical importance. Here, for the first time, we characterize the antimicrobial activity of some selected frog skin-derived antimicrobial peptides (AMPs) against C. jeikeium by determining their minimum inhibitory and bactericidal concentrations (MIC and MBC) by a microdilution method. The results highlight esculentin-1b(1-18) [Esc(1-18)] and esculentin-1a(1-21) [Esc(1-21)] as the most active AMPs with MIC and MBC of 4–8 and 0.125–0.25 µM, respectively, along with a non-toxic profile after a short- and long-term (40 min and 24 h) treatment of mammalian cells. Overall, these findings indicate the high potentiality of Esc(1-18) and Esc(1-21) as (i) alternative antimicrobials against C. jeikeium infections and/or as (ii) additives in cosmetic products (creams, deodorants) to reduce the production of bad body odor.

Development of Antimicrobial Peptides from Amphibians

“…Esc (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18) and Esc showed the ability to kill this bacterium at a concentration range from 0.125-0.25 µM, along with a non-toxic profile after short-and long-term (40 min and 24 h) treatment of mammalian cells. These results reinforce the potentiality of these peptides as alternative antimicrobials against C. jeikeium infections and/or as additives in cosmetic products (creams, deodorants) to reduce the production of bad body odor [21].…”

Temporin G, an amphibian antimicrobial peptide against influenza and parainfluenza respiratory viruses: Insights into biological activity and mechanism of action

“…A purity of 95% was obtained via reverse-phase high-performance liquid chromatography (RP-HPLC) using a gradient of 0.1% trifluoroacetic acid in acetonitrile from 20% to 100% in 30 minutes at a flow rate of 1 ml/min (Gemini 5 µm C18 110A HPLC Column 250 × 4.6 mm). 22 The molecular mass of the peptides was verified by mass spectrometry. All peptides were dissolved in water; stock solutions of 2 mM were prepared.…”

“…The cytotoxicity of the peptides was evaluated by the inhibition of MTT reduction into formazan crystals 19,22,24 and by the trypan blue staining assay. 25 Particularly, in the MTT assay, A549 cells were seeded in 96-well plates at a density of 2 × 10 4 cells/well in 100 μL of complete DMEM without phenol red for 24 hours at 37°C.…”

“…Interestingly, edge-to-face aromatic interaction between a conserved Phe (from different locations) and HA2 Trp 21 was observed in the complexes of other peptides and antibodies able to bind to group 1 H1 HA. 32,37,38 Furthermore, Trp 21 , together with Tyr 22 and Gly 23 , represent the highly conserved C-terminal region of the fusion peptide (HAfp23). 39 Overall, these results have demonstrated that TG likely binds HA at the HA1/HA2 interface, suggesting its F I G U R E 5 Pre-treatment of A549 cells with TG does not affect the replication of PR8.…”

The Antimicrobial Peptide Esc(1-21) Synergizes with Colistin in Inhibiting the Growth and in Killing Multidrug Resistant Acinetobacter baumannii Strains

“…We have previously characterized a 21-residues long derivative of the frog-skin AMP esculentin-1a, namely Esc(1-21). It is active against Gram-positive and Gram-negative bacteria, and it is endowed with the capacity to kill the human pathogen Pseudomonas aeruginosa and to enhance the growth inhibition activity of aztreonam [ 22 , 25 , 26 ]. In this work, with the aim to re-evaluate the efficacy of colistin, we investigated whether the usage of this drug in combination with Esc(1-21) had a synergistic effect in inhibiting the growth and/or in killing colistin-resistant clinical A. baumannii strains along with the underlying molecular mechanism.…”